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FIELD OF THE INVENTION
This invention is directed generally to irrigation systems for irrigating large land areas and more specifically is directed to elongated irrigation systems that move in substantially controlled manner over a land area to accomplish irrigation of the land area. More specifically, the present invention is directed to an irrigation system that extracts water from an elongated water supply source, such as a ditch or water pipe, for the purpose of irrigation and which irrigation system is automatically movable and automatically steered over a land area for extended lengths of time without any requirement for significant attention by personnel.
BACKGROUND OF THE INVENTION
A valuable asset to the irrigation industry has been the development of irrigation systems that travel while sprinkling large land areas with water and require virtually no personnel attention during operation. Substantial elimination of the labor costs that were earlier required has greatly enhanced the commercial success of large field irrigation. Although many different types of irrigation systems have been developed over the years, the type of irrigation system that is most prevalent is the circular irrigation system which incorporates a plurality of sprinkler pipe sections that are each supported by a mechanism for inducing movement to the pipe sections. In circular irrigation systems a central pivot tower is provided that also serves as a water supply and one extremity of the irrigation system is connected thereto causing the entire irrigation system to revolve about the pivot during continuous irrigation operations. Although circular irrigation systems have been quite successful, it is clear that greater crop yields and lower cost irrigation would be achieved if the irrigation system were capable of irrigating rectangular land areas or other specifically shaped land areas as opposed to circular areas. One attempt to accomplish more rectangular irrigation through the use of circular irrigation systems is through the use of corner irrigation spray devices that are activated only during four small segments of each revolution of the irrigation system. Although the increase of land area irrigation through the use of irrigation guns is not insubstantial, it would nevertheless be commercially desirable to provide an irrigation system that was capable of irrigating the entirety of a large rectangular land area.
In the past, irrigation systems have been developed for irrigation of rectangular fields, but in order to provide for proper operation of the irrigation system, it is generally deemed necessary that a plurality of tracks or guideways be provided in order to physically guide the irrigation system over the land area. Of the number of patented devices that have been developed with track or guideway control in mind, U.S. Pat. No. 3,608,827, to Kinkead is typically representative. Linearly movable irrigation systems have also been developed that do not necessitate the use of tracks or guideways such as taught by U.S. Pat. No. 3,613,703, to Stout which utilizes a guide rail 52 for reference during movement over a land area and traverses by alternate movement and pivoting of each of the ends of the system. In the case of the structure identified in the patent to Stout the ambulatory irrigation system is so arranged and controlled that each end of the composite line alternately can be caused to travel a predetermined distance along an arcuate path with the opposite end of the composite line temporarily being substantially at the center of curvature of the arcuate path and with the entire line thus swinging forwardly in alternate angular direction as it moves over the land area. More simply, one extremity of the irrigation system remains static and serves as a pivot during a portion of the movement and the sequence is then reversed causing the other extremity to remain static while the first extremity is caused to move. The ends of the system are not capable of simultaneous movement.
It is considered desirable to provide a linearly movable irrigation system that does not require a track or guideway to control movement thereof such as is the case with Kinkead U.S. Pat. No. 3,608,827 and which does not cause excessive water distribution on certain of the land section such as is likely to occur when each end of the irrigation system alternately moves forward.
U.S. Pat. No. 3,707,164 to Clemons and U.S. Pat. No. 3,974,845 to Indresaeter disclose linearly movable irrigation systems which do not require a track or fixed guideway for control of the system movement. Clemons teaches a method and apparatus for maintaining an irrigation system within predetermined distance from an elongated reference line. In one embodiment, Clemons selectively energizes adjacent tractors to provide a steering action relative to the guide and in another embodiment the tractor wheels are also turned simultaneously to move the irrigation system toward or away from the reference guide. Clemons also teaches maintaining the alignment between adjacent tractors by varying the flow of hydraulic fluid to hydraulic motors on the tractors for speed control. It should be noted that the steering control systems taught by Clemons employ control and power systems at substantially each mobile support unit. Further, the control systems of Clemons are actuated by only a single type of input so that the system response is corrective of only the particular input selected.
U.S. Pat. No. 3,974,845 to Indresaeter teaches an irrigation system which is controlled by stopping and starting mover units located at extremities of the system. As described therein, the control system is provided with inputs functionally related to the linear displacement from the guide reference of the mover unit adjacent the guide reference and to the angular alignment of the irrigation system with respect to the guide reference. The correction of either linear or angular misalignment is accomplished by causing the entire irrigation system to pivot about one extremity or the other to maintain the system within preselected limits. Lateral displacement can be corrected only by a substantial number of correcting manuevers. Further, there is no input signal related to the stresses being developed in the irrigation pipe spans in order to preclude corrective action which could result in excessive system stresses.
Accordingly, it is a primary feature of the present invention to provide a novel linearly movable irrigation system that moves in substantially linear manner over a land area and is capable of irrigating the entirety of a generally rectangular land area or irrigating a land area of an irregular shape.
It is also a feature of the present invention to provide a novel linearly movable irrigation system whereby control of the movement of the system is accomplished by a first control system steering a mover unit adjacent an elongated reference and an independent second control system maintaining the relative rotation of the irrigation pipe spans relative to the steerable mover unit.
It is an even further feature of the present invention to provide a novel linearly movable irrigation system that moves in linear manner over a land area and, in the event of the occurrence of predetermined misalignment of the irrigation system relative to the reference, the irrigation system is automatically self-steering to maintain its travel within a defined boundary.
It is yet another feature of the present invention to provide a novel linearly movable irrigation system employing sensing devices for determining angular alignment of the irrigation pipe spans with respect to a pivot located on the steerable mover unit and for determining the stresses in the irrigation pipe spans and controlling the angular alignment and stress by movement relative to the steerable mover unit.
It is also an object of the present invention to provide a novel linearly movable powered mover unit adjacent a reference such as an elongated guide surface which may be straight or curved as desired, wherein the powered mover unit is provided with a control mechanism that senses linear displacement of the mover unit relative to the reference for steerably controlling travel of the mover unit relative to the elongated reference.
It is another object of the present invention to provide a novel linearly movable irrigation system in which angular alignment and stresses in the irrigation pipe spans are controlled by movement relative to a powered mover unit and independent from a fixed guide reference.
It is also a feature of the present invention to provide a novel linearly movable irrigation system wherein a plurality of individually supported and driven sections are incorporated into an elongated irrigation system and wherein movement of each of the sections is controlled by its angular relationship with an adjacent irrigation section, such angular relationship control overridden under certain circumstances by control signals received from a power and control portion of the irrigation system.
SUMMARY OF THE INVENTION
The present invention is directed to a linearly movable steerable irrigation system that is adapted to move in substantially linear manner for irrigation of a large generally rectangular land area. The irrigation system is adapted to move automatically in response to its position relative to an elongated reference such as an elongated straight or curved guide surface, guide rail, guide line or guide beam during irrigation operations and in response to the angular alignment and stresses of irrigation pipe spans relative to a powered mover unit adjacent the elongated reference. Sensing apparatus carried by a powered mover unit of the irrigation system is capable of sensing both linear displacement of the mover unit relative to the elongated reference and the angular alignment and stresses of the irrigation pipe spans relative to the powered mover unit and automatically self-correcting the direction of movement in the event the irrigation system has moved beyond allowable limits of linear displacement, angular misalignment or system stresses.
The irrigation system includes a powered mover unit that is provided at one extremity thereof or intermediate the extremities of the system and which will typically be directly connected to linear displacement, angular misalignment, and system stress sensors that determine relative positioning of the irrigation system. To the powered mover unit may be connected a plurality of irrigation sections each comprising an irrigation span that is supported by any suitable mobile support such as wheels, tracks, ambulatory mechanisms, etc. that is capable of accomplishing movement of the irrigation system over the land area. An elongated irrigation conduit being a composite of a number of interconnected sections of irrigation pipe will be supported by the spans above the land area and will cause distribution of water on the land area by means of sprinkler devices carried by the various sections of water supply pipe. Each of the self-driven sections or spans of the irrigation system may be controllably activated and deactivated by the angular relationship thereof to other spans or sections to accomplish controlled movement of the spans of the irrigation system. Conventional angular detection sensors may be employed to detect angular misalignment between the respective sections of the irrigation system. When such angular misalignment reaches a predetermined value, the drive mechanisms controlled by the angular detecting device for each section will be energized causing the drive means to impart driving movement to that particular section of the irrigation system. Such driving will continue until sufficient movement of that section has occurred to change the angular relation detected by the angular detecting device to another predetermined value, at which time the drive mechanism for that irrigation section will be de-energized.
For accomplishing steering control responsive to signals received by the powered mover unit from the linear displacement sensors contacting the elongated reference, steering pistons on a steerable powered mover unit are actuated to rotate the mobile support, such as wheels, and maintain the steerable powered mover unit within preselected displacement limits of the elongated reference. Hence, continuous irrigation system movement can be maintained when minor steering corrections are being made and the system is enabled to promptly respond to correcting signals.
Extending from the steerable mover unit may be a plurality of irrigation pipe spans and a powered mover unit connected substantially at the extremity of the connected pipe spans. The extending pipe spans may be pivotally connected to the steerable mover unit to define a reference for measuring angular alignment of the irrigation spans with the steerable mover unit and for measuring stresses within the pipe spans as a function of the reference pivot. The angular alignment and stresses of the irrigation pipe spans are maintained within preselected limits by varying the average speeds of the steerable mover unit and the outboard mover unit to obtain rotation of the extending pipe spans relative to the pivot. For example, mover unit average speed may be varied by controlling the duration for energizing the mover unit motor over a selected time interval, i.e. controlling the duty cycle of the motor. Varying the duty cycle of the inboard and outboard mover unit motors will produce relative pivotal movement of the outboard unit about the inboard unit. When this relative pivotal movement has continued sufficiently to satisfy the requirements of the control signal, another control signal will be provided causing both extremities of the irrigation system to move at the same or different average speed, causing the entire irrigation system to move in substantially linear or controllably turning manner across the land area. Upon movement of the irrigation system sufficiently to traverse control boundaries defined by the stress and angular misalignment sensors, another control signal will be issued, causing the opposite extremity of the irrigation system to remain static or to be controllably slowed while the other extremity of the irrigation system is allowed to continue moving. The resulting effect is a relative pivoting of the entire irrigation system about the steerable mover unit. In other words, the irrigation system will move across the land area in substantially linear manner unless for some reason it should become over-stressed or angularly misaligned relative to the steerable mover unit. This can be caused by traversing of the irrigation system over undulations in the terrain or by other than straight line positioning of the reference such as might occur if the reference is designed to cause tracking of the irrigation system to irrigate an oval land area.
The present invention is also directed to the method of accomplishing irrigation of land areas, wherein the elongated irrigation system, capable of movement across a land area in substantially linear manner, is also capable of being steered automatically so as to correct any lateral displacement from an elongated reference. The irrigation apparatus, under the novel method of controlling the operation thereof, is capable of irrigating generally rectangular land areas and because of its automatic steering capability, is also capable of traversing land areas that are of irregular configuration. Each extremity of the irrigation system is capable of independent movement responsive to control signals received from a control facility and may move at different speeds, stop, or move at the same speed as the opposite extremity of the irrigation system. Also, the power and control facility for the irrigation apparatus may be located intermediate the extremities of the irrigation system or at either extremity thereof within the teachings of the present invention.
Water supply for the irrigation system may take the form of an elongated ditch from which water is extracted by suction or it may take the form of an elongated closed water supply system such as a pipe having a plurality of water supply connections that are automatically received and released in such manner as to provide substantially continuous water flow as the irrigation system traverses its designated path of travel.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above-recited features, advantages and objects of the present invention as well as others which will become apparent, are obtained and can be understood in detail, more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings, which drawings form a part of this specification. The present invention, both as to its organization and manner of operation may best be understood by way of illustration and example of certain preferred embodiments when taken in conjunction with the accompanying drawings.
IN THE DRAWINGS
FIG. 1 is a plan view partially in schematic form illustrating a linearly movable irrigation system that is constructed in accordance with the principles of the present invention.
FIG. 2 is a plan view of a motorized steerable mover unit and illustrating the position of the various sensors on the mover unit frame.
FIG. 3 is an elevation view illustrating one embodiment of a displacement sensor for determining the position of the mover unit frame relative to an elongated reference.
FIG. 4 is a schematic illustration of control system input parameters.
FIG. 5 is a schematic illustration of the basic control system logic.
FIG. 6 is a graphic representation of the track of controlled movement of the irrigation system in response to various input signals.
FIG. 7 is a block diagram schematic of a control unit for evaluating input information and determining an appropriate response in accordance with a preferred embodiment of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the drawings and first to FIG. 1, there is depicted a self-driven irrigation system of the type that is adapted to move across a large land area to be irrigated and to follow elongated reference while controlling an extending string of irrigation pipe spans to maintain the stresses in the irrigation pipe spans and the rotation of the elongated string of pipe within predetermined values. As shown in FIG. 1, the irrigation system incorporates a motorized steerable mover unit depicted generally at 10. On the mover unit 10 may be provided an engine, pump, and generator unit 22 providing mechanical and electrical power for operation of the irrigation system. Mover unit 10 is in communication with a water supply source 14 and may extract water from the water supply and transmit it under pressure to a plurality of irrigation spans 16 from which it is evenly distributed on the land surface by a plurality of conventional sprinkler devices that are carried by the irrigation pipe spans.
Extending from the mover unit 10 are a plurality of irrigation sections or spans 16 that comprise a structural framework for support of each of the various sections of irrigation water supply pipe that are interconnected to form the irrigation system. Each of these spans or sections 16 may be supported by a mobile base 17, the respective mobile bases 17 being provided with wheels, tracks, ambulatory devices, etc. in order to provide the mobility that causes the irrigation system to traverse the land area being irrigated. An outboard mover unit 18 is provided preferably adjacent the end of the irrigation span removed from water supply 14. Mover unit 18 may be provided with an individual power means which is controlled so as to permit rotation of the plurality of interconnected irrigation pipe spans 16 with respect to the steerable mover unit 10, as will be hereinafter explained in more detail.
For controlling the track of the irrigation system over the land area, an elongated reference 12 may be provided. The elongated reference may take many suitable forms that enable position sensing devices to react with the reference and steer the steerable mover unit to maintain a predetermined distance between the steerable mover unit and the elongated reference 12. For example, the reference may be a guide rail supported above the ground on posts, it may take the form of a supported guide wire and it may also take the form of a guide surface formed by the water supply, such as an external wall of a concrete lined ditch that is partially embedded in the ground or supported on the surface of the land area. The reference, where a straight line reference is desired, may take the form of a laser beam or other suitable beam that may be appropriately sensed. If the novel sensing device, hereinafter described, which is subject of the present invention is employed, a supported guide wire is the preferred form of the elongated reference 12. While the reference 12 is shown to be in the form of a straight line in FIG. 1, it is not intended to limit the present invention solely to use under conditions where the reference takes the form of the straight line. The reference 12 may be curved in any suitable form that is appropriate for guiding the track of the irrigation system about the land area to be irrigated.
Referring now to FIG. 2, there may be seen a plan view of steerable mover unit 10. A frame 34 is provided which is mounted on a suitable mobile support for traversing a terrain suitable for irrigation, which mobile support may conveniently take the form of wheels 38 supported on axles 36 which are rotatably mounted on frame 34. Wheels 38 may be rotated to steer mover unit 10 either toward or away from elongated reference 12 so as to maintain a predetermined distance between the mover unit 10 and elongated reference 12. Sensor units 30 may be mounted on sensor support arms 40 which are connected to the wheel axles 36 which are nearest the elongated reference 12. In operation, the leading sensor 30 at each wheel location is selected to provide an input signal, the leading sensor being determined by the direction of travel of mover unit 10. Electrical output lines 32 from each sensor 30, conveniently carried in cable bundle 33 mounted on frame 34, provide a plurality of output signals from each sensor 30 as inputs to control unit 24.
Electrical outputs 32 from sensors 30 are used to control the steering mechanisms 44 and 42 and control the position of mover unit 10 relative to elongated reference 12. Tie rods 37 connect the pair of wheel axles 36 at each end of mover unit 10 so that simultaneous movement of each pair of wheels 38 will occur. Steering actuators 42 and 44 may conveniently take the form of hydraulically-actuated pistons which are actuated through hydraulic output lines 45, which may conveniently be interconnected with the output of the water pump (not shown) contained in engine section 22. Actuators 42 initiate movement of mover unit 10 away from elongated reference 12, whereas actuators 44 initiate movement toward elongated reference 12. In a preferred embodiment, a sensor 30 will activate the steering mechanism for the pair of wheels 33 on which it is mounted. In this manner, each end of mover unit 10 will move toward or away from elongated reference 12 as determined from the outputs from sensors 30. A particular displacement sensor contemplated as part of the present invention may be seen by reference to FIG. 3, as more particularly hereinafter discussed.
In FIG. 2 there may also be seen engine section 22 which is depicted in block form. Engine section 22 may contain a motor powered by conventional fuel sources such as gasoline, butane, diesel fuel, etc. and interconnected with a conventional generator for supplying electrical energy to power mover unit 10 and other mover units interconnected therewith. The engine may be conventionally connected to a pump via a power take-off unit to provide a pressurized supply of water to the irrigation pipe spans for suitable distribution through sprinklers to the land area. A portion of the pump output may be diverted through hydraulic lines 45 to activate steering actuators 42 and 44, as hereinabove discussed. The output from the electrical generator is supplied to electrical motors for powering the mover units, and may be controlled as hereinbelow discussed to maintain movement of the irrigation system across the land area. Referring again to FIG. 2, there may be seen a pressurized water supply pipe 26, connected to the output of the pump and engine section 22 and suitably supported on frame 34 by a tower-like support structure (not shown). Water pipe 26 is connected to pivot section 28 and thereafter interconnected with irrigation pipe span 16. Pivot 28 defines a reference point with respect to the plurality of irrigation pipe spans 16 which extend outwardly from pivot 28 and which interconnect with mover unit 18, as depicted in FIG. 1. As hereinafter described, the rotation of irrigation pipe spans 16 about pivot 28 is measured by rotary transducer 50 which provides an output signal 52 which is functionally related to the amount of angular rotation of irrigation pipe span 16 about pivot 28.
Pivot 28 is mounted on frame 34 so that pivot 28 may be deflected along the line of the interconnected irrigation pipe span 16. The direction and amount of deflection of pivot 28 is functionally related to the tension and compression stress forces which occur in the string of interconnected irrigation pipe spans 16. Control of these stress forces is important to maintaining control of the irrigation system, as more fully discussed hereinbelow. The deflection of pivot 28 is detected by deflection linkage 54 and translated into a rotary movement which is detected by deflection rotary transducer 56. Deflection transducer 56 thereby provides an electrical output signal 58 which is functionally related to the magnitude and direction of the stresses which are obtained in the interconnected irrigation pipe spans 16.
The extending irrigation pipe spans 16 must be maintained in a relationship to adjacent pipe spans to permit movement about pivot 28 to functionally represent the condition of the entire pipe string. Such a relationship is maintained by sensing the angular relationship between adjacent pipe spans and controlling the intermediate mobile bases 17, as shown in FIG. 1, to correct misalignment on a span-to-span basis. The intermediate mobile bases 17 are normally energized and then controllably de-energized to maintain each span 16 within a preselected angular relationship with adjacent spans. The entire extending pipe string is thereby maintained as a substantially straight line so that pivot 28 may be used as an appropriate reference.
The outputs 52 and 58 from pivot rotation transducer 50 and deflection transducer 56, respectively, are provided as inputs to control unit 24 to obtain a first output 60 to control the motor of inboard mover unit 10 and a second output 62 which controls the motor of outboard mover unit 18 which is displaced from mover unit 10.
It is readily apparent from the foregoing discussion that, according to the present invention, movement of the irrigation system in a controlled fashion is accomplished by first steering mover unit 10 with respect to an elongated reference 12 to independently establish the track of mover unit 10 across the land area which is to be irrigated. The interconnected plurality of irrigation pipe spans 16 is then maintained in a controlled relationship with respect to mover unit 10 by controlling mover unit 18 which may conveniently be located near the end of the interconnected spans of irrigation pipe. As fully discussed hereinbelow for FIGS. 4 and 5, the relationship between the extending irrigation pipe spans and the steerable mover unit 10 permits the string of irrigation pipe to be maintained in a generally perpendicualr relationship with respect to elongated reference 12 and yet allow some variation in its angular relationship to provide corrective movement which relieves stresses occurring along the interconnected pipe spans.
Referring now to FIG. 3, there is shown displacement sensor 30 according to one embodiment of the present invention. Displacement sensor 30 includes an elongated sensor support member 70 which is mounted on mover unit 10 by pivotally connecting elongated sensor support member 70 to displacement sensor support 40. Elongated sensor support 70 is eccentrically mounted at pivot 78 to displacement sensor support frame 40. The eccentric location of pivot 78 is provided so that elongated sensor support 70 will assume a preselected angle with respect to the vertical when in a free hanging condition. As explained below, the free hanging angle is a limit which determines a maximum displacement of mover unit 10 from elongated reference 12.
As mover unit 10 traverses the land area to be irrigated, sensor support member 70 contacts elongated reference 12 and rotates about pivot 78 as mover unit 10 moves variably in relationship to its displacement from elongated reference 12. A plurality of switches are mounted on elongated reference 70 which are selectively energized to detect the angular position of elongated sensor support 70. As depicted in FIG. 3, switches 72, 74 and 76 illustrate the relationship of switch outputs to various angular conditions.
Position A of FIG. 3 depicts movement of mover unit 10 toward elongated reference 12. Switches 76 and 74, which may conveniently take the form of mercury limit switches in which contact is completed when mercury pools in one end or the other, are rotated so as to complete the circuits connected therewith (not shown). Switch 72 has moved to a level position where the mercury is pooled in an intermediate location so that contact is not made at either end of switch 72. The output from switches 76 and 74 may be used to activate the steering mechanism as hereinabove discussed to steer mover unit 10 away from elongated reference 12 until elongated sensor support 70 reaches position B. At condition B, sensors 76 and 72 now have completed electrical contacts and sensor 74 is in the intermediate condition. The output from the position B condition may be used to activate the steering mechanism to return the wheels to a neutral position. If mover unit 10 begins to drift away from elongated reference 12, elongated sensor support 70 tends to swing toward elongated reference 12 as a result of the eccentric mounting of support 70 about pivot 78. This movement may continue until a condition C is reached where switches 74 and 72 are closed and switch 76 is in an intermediate position. This condition may be used to actuate the steering mechanism to mover unit 10 toward the elongated reference 12 until a position B condition is again obtained.
Displacement reference sensor 30 is also used as a means to shut down the irrigation system if movement of the mover unit 10 toward or away from elongated reference 12 exceeds a preselected value. This preselected value may be determined by the free hanging angle of eccentrically mounted sensor support 70 so that in the free hanging condition switches 72, 74 and 76 are all closed. Conversely, if mover unit 10 approaches elongated reference 12 so that the angular displacement equals that of the free hanging angle, switches 72, 74 and 76 all close and system operation will again terminate until manual correction is obtained. The above-described displacement sensor assembly, which is a part of the present invention, may be seen to be a device which is simply constructed but which is capable of providing output signals indicative of a variety of displacement conditions, including a fail-safe shut down signal. The position of mover unit 10 may be controlled within relatively narrow limits with respect to elongated reference 12. It will be noted that the system is also well adapted to tracking curves defined by elongated reference 12 as the land area is traversed. Elongated reference 12 may also be the edge of a water canal constructed to extend above the ground a distance sufficient to engage elongated support member 70.
As mover unit 10 tracks along elongated reference 12, the plurality of interconnected irrigation pipe spans 16 which are interconnected between the mobile pivot 28 of inboard mover unit 10 and outboard mover unit 18 are moved along the area to be irrigated as mover units 10 and 18 are powered over the land area. It will be appreciated that the distance between inboard mover unit 10 and outboard mover unit 18 can be quite large and may approach a quarter of a mile in the largest irrigation systems. This extending pipe string may tend to lead or lag the movement of mover unit 10 so as to produce a relative rotation of extending pipe span 16 about mobile pivot 28. This relative rotation is detected by rotary transducer 50 and translated into electrical signal 52 which is functionally related to the magnitude and direction of rotation with respect to some reference position, which may conveniently be an imaginary line generally vertical to the direction of movement of mover unit 10. It is desirable to maintain this angle of rotation as small as possible in order to maximize the coverage of the irrigation system and to minimize the drag which is exerted on the irrigation pipe spans 16.
In addition to relative angular movement about mobile pivot 28, the position of outboard mover unit 18 with respect to inboard mover unit 10 may vary slightly in distance as the land area is traversed. This variation in distance along the interconnected irrigation pipe span 16 introduces stresses in the pipe spans 16, which may be either in tension or compression as mover unit 18 moves either toward or away from mover unit 10, respectively. These stress forces must be measured and corrective action taken to relieve the stresses before damage to the irrigation system occurs. In one embodiment of the present invention, the stresses produce a lateral deflection of pivot 28. This lateral deflection is detected by linkage 54, as hereinabove discussed, and translated into an output signal 58 from rotary transducer 56 functionally related to the stress vector within irrigation pipe spans 16.
THEORY
The basic mechanism for controlling the relationship between the two mover units and, therefore, the rotation of the irrigation spans about the mobile pivot point and the stress in the irrigation spans, is to control the average speed of each mover unit. The average speed may be controlled in a variety of ways, depending on whether the drive motors are AC or DC motors. If AC motors are used, the average speed may then be varied by either varying the frequency of the power supply or varying the time period during which energy is supplied to the motors. Although both methods are considered to be within the contemplation of the present invention, the preferred embodiment discussed hereinbelow involved the selected energizing of the motors which power the inboard and outboard mover units.
Referring now to FIG. 4, there may be seen a schematic of the system parameters which are monitored to control movement of the inboard 10 and outboard 18 mover units. The point of reference is pivot 28 on inboard mover unit 10. Stresses in the irrigation pipe spans result in deflection, ±D, of pivot 28. The direction of the deflection, D, defines the nature of the stress as either compression or tension. The amount of deflection, D, is functionally related to the magnitude of the stress forces in the irrigation spans 16.
Rotation of the irrigation spans 16 is also measured relative to pivot 28. This angular rotation, ±θ, represents the lead or lag of the extending pipe spans with respect to mover unit 10. Hence, the entire extending irrigation system is controlled with reference to pivot 28, which reference is mobile with the controlled movement of mover unit 10 along an elongated reference.
The deflection and rotation input parameters are then maintained within selected values by controlling movement of outboard mover unit 18 relative to inboard unit 10. Specifically, a duty cycle is computed for operating the motor of each mover unit to obtain the desired relative movements. If the duty cycle of the inboard mover unit 10 is chosen to be Tp, then the duty cycle of the outboard mover unit will be defined to be
Te=Tp-ΔT.
ΔT is calculated from the input parameters as
ΔT=f[A(D)+B(θ)]=Tp-Te
where A and B are constants which weight input parameters D and θ, respectively. ΔT may be maintained within preselected limits by varying the duty cycle Te of outboard mover unit 18. If necessary, the duty cycle Tp of inboard mover unit 10 can be varied to correct a large deviation.
FIG. 5 shows a flow diagram of information through a control unit, hereinafter discussed as FIG. 7. The basic inputs (D, θ) are first examined. If D≠O, an angular correction is computed to return D in a correcting direction. Once D=O, the resulting angle θ is then examined. An angular correction is then generated to return θ toward a neutral reference condition. To provide the necessary angular corrections, the motor duty cycles (Te, Tp) for the respective mover units are determined for the next time interval. The motors are then energized for proportionate times to obtain the desired relative movement.
FIG. 6 is a graphic representation of the various relationships which may occur between inboard mover unit 10, whose movement is depicted at time intervals denoted by Tp and outboard mover unit 18, whose movement is denoted at time intervals Te.
Referring now to FIG. 6, at time To, the string of pipe spans is lagging movement of the inboard mover unit. To correct this condition over the next timing interval, the outboard mover unit is energized for a time period Te1 and the inboard mover unit is energized for a shorter time period Tp1 so as to partially correct the rotational variance by time T1. A correction is still required at time T1 so the outboard unit is again energized for a time interval Te2 and the inboard unit for a time interval Tp2, which is less than Te2. Accordingly, the selective energizing of the mover units has caused the angular discrepancy to be corrected by time T2 so that the next duty cycles, Te3 and Tp3, are equal and the units advance the same distance along the land areas without rotation about the inboard pivot point.
At time T4, there may be seen a condition of tension in the irrigation pipe spans as indicated by lateral displacement of the outboard mover unit away from the inboard mover unit and detected by a lateral displacement of the inboard pivot point, as hereinabove discussed. In order to reduce the tension, the outboard unit must be caused to move toward the inboard unit and this relative movement is obtained by energizing the outboard unit for a time period Te4 and the inboard unit for a time period Tp4, which is less than Te4. Accordingly, at T5, the outboard unit has moved somewhat toward the inboard unit and thereby relieved compression in the string of irrigation pipe spans.
Referring again to FIG. 6, there is depicted at time T6 a condition where the outboard mover unit has moved ahead of the inboard mover unit. This rotation is detected by the pivot rotary transducer and a control signal is provided to energize the inboard mover unit for a time period Tp6 and the outboard unit for a time period Te6, which is less than Tp6, whereby the leading condition is partially corrected by time T7. Since a deviant condition still exists at time T7, the inboard unit is again energized for a time interval longer than the outboard unit in order to obtain a corrected condition at T8. A control unit, hereinafter discussed, senses the corrected angular relationship and thereby causes the inboard and outboard units to be energized for equal time intervals Tp8 and Te8, respectively.
At time T9 there is depicted a condition of compression in the irrigation pipe spans where the outboard unit has moved toward the inboard unit. Again, the lateral deflection of the pivot point is detected and an output signal is provided which energizes the inboard unit for a time interval Te9, which is less than Tp9. This results in the outboard unit slightly lagging the inboard unit and thereby tending to increase the displacement between the two mover units to reduce the compression in the irrigation pipe spans. Again, an allowable rotation is obtained in order to correct these stresses in the irrigation pipe spans.
In FIG. 7 there is depicted in schematic block diagram form a control system which monitors electrical signal inputs from the transducers located on the inboard mover unit 10 and thereafter derives duty cycles for the inboard mover unit 10 and outboard mover unit 18 drive motors. In particular, the proportional motor control system 80 receives inputs relating to the condition of the extending irrigation pipe span 16 relative to pivot 28, as shown in FIG. 1. Rotation of the extending irrigation pipe section 16 about pivot 28 is detected by rotary transducer 50, which provides an output signal which is functionally related to the magnitude and direction of this rotation. The lateral deflection of the pivot 28 is functionally related to the magnitude and direction of stresses which are developed in the irrigation pipe spans and this lateral deflection is detected by a deflection linkage to cause rotation of deflection transducer 56, which produces an output signal functionally related to the stress in the irrigation pipe spans.
The output signals from transducers 50 and 56 are each input to the proportional motor control system 80 through operational amplifiers 81. Each signal is input to analog multiplexer 82 which selectively presents either the rotation analog signal or the stress analog signal through operational amplifier 85 to analog-to-digital converter 86. The desired input is selected for presentation by control unit 84. Analog-to-digital converter 86 receives the output from amplifier 85, which is typically an analog voltage of zero to two volts and converts the voltage input to a digital output. The output from analog-to-digital converter 86 is presented to data bus 90 through buffers 87 which isolate the converter 86 from the data bus 90.
As hereinabove discussed, each of the input signals must be weighted in order to obtain the desired overall system response. Accordingly, switches 92 and 93 are provided, which are a portion of a dual inline package whose output can be varied and thereby provide the desired constant weighting output.
In addition to the primary system parameters, other input information is provided to data bus 90 for overall system control. A speed selector switch 95 is used to vary the average speeds of both the inboard and outboard mover units simultaneously. The selected average speed representation is presented from speed switch 95 through buffer 96 to data bus 90. Yet another data input is provided to monitor the condition of various switches 98 throughout the irrigation system. Switch data 98 is provided to optical isolator 99 to prevent system anamolies, such as voltage spikes resulting from static and sparks, from passing through to data bus 90. Buffer 96 interconnects the data from optical isolator 99 to data bus 90. As hereinafter explained, particular input data is selected for presentation to the data bus 90 in a programmed sequence and each input unit receives an enabling signal which directs the input to be presented to data bus 90.
The input signals on data bus 90 are then presented to the computational portion of the control unit through buffer 101 to bus driver and controller 102. Bus driver 102 can transmit data signals either from the data bus 90 to a processing unit or accept signals from processing unit and transmit data back along data bus 90. Bus driver 102 also includes a control unit which provides enabling signals to various system components to obtain sequential presentation of inputs to the system and the acceptance of outputs from the system.
Input data on data bus 90 is presented to central processing unit 104. Central processing unit 104 is, in essence, a mini-computer which is preprogrammed to provide a variety of processing functions. Central processing unit 104 is driven by clock 105 to obtain and evaluate data in a preselected sequence. Clock 105 also provides an output pulse train which is used to control the mover unit motors, as hereinbelow discussed. Additional system components are interconnected with central processing unit 104 to assist the processor 104 in its computations.
As central processing unit 104 is clocked through its program sequence, information from memory units external to central processing unit 104 must be called for use and intermediate calculational results must be returned to memory units for temporary storage. Two different types of memory units are required to assist central processing unit 104. A first programmable, read only, memory unit 112 is utilized to instruct central processing unit 104 on the calculational steps needed to process the input data. Programmable memory units 112 are not used for intermediate storage, but store preprogrammed data and instructions for the central processing unit 104. Readable and addressable memory units 114 are provided for intermediate data storage locations. Readable memories 114 can accept data for intermediate storage and thereafter present the stored data to data bus 90 for further use in the data processing.
Central processing unit 104 selectively addresses the programmable memory units 112 and addressable memory units 114 along address bus 106. In addition, a decoder 110 is connected to address bus 106 and provides a plurality of outputs which enable the various memory units to accept or transfer data along data bus 90. Other decoder units 116 are connected to address bus 106 for providing data input and output enabling signals which enable the various data input and output units to respond to the data on data bus 90. The input and output control units 116 are further selectively enabled by output signals from bus driver and controller 102 as data is being selected for input to the system and control signals are being selected for output from the system.
Clock generator 105 also provides another output to pulse generator 115. Pulse generator 115 divides the high frequency output from clock 105 to obtain a train of pulses of 20 millisecond (ms) duration. The 20 ms pulse output from generator 115 is presented to central processing unit 104 along data bus 90 and acts as the basic control timing pulse chain.
As hereinabove discussed, central processing unit 104 computes the duty cycle for each mover unit based on the input parameters. Central processing unit 104 then counts the 20 ms pulses from pulse generator 115 and provides an output signal to energize each mover unit until the pulse count reaches the count corresponding to the computed duty cycle. Thus, each duty cycle is computed for the next minute to a 20 ms precision.
After central processing unit 104 has completed its calculations, the output motor control signals are impressed on data bus 90 and driven along by bus driver 102 through buffer 101 for presentation to output registers 118. When enabled by signals from control units 116, registers 118 accept the data presented along data bus 90. The proportional motor control signals are then presented to optical isolators 120 and then to solid state relay 122 for actual motor control. Optical isolator 120 isolates the incoming data from the actual motor control system in order to prevent spurious electrical noise from interfering with the control system. Solid state relay 122 receives the control information and energizes the motors 124 on the mover units for the duty cycle which has been calculated for each particular mover unit over a selected data interval. Typically, a one minute data interval may be used and a duty cycle of all, or a calculated portion, of that minute will be computed and used to energize the respective mover units to obtain the required system response.
It will be understood that a variety of available components may be utilized to perform the functions described for each of the diagram blocks in FIG. 7. By way of example, suitable integrated circuits for the central processing unit 104, clock/generator drive 105, bus driver and controller 102, programmable read only memories 112, readable-addressable memories 114, and others are described in a catalog from Intel Corporation of September, 1975, and entitled 8080 Microcomputer Systems User's Manual.
In view of the foregoing, it is apparent that there has been provided a unique method and apparatus for accomplishing irrigation of large land areas, wherein irrigation apparatus is employed that is not tethered to a physical structure, but rather moves over a land area within limits bounded by allowable error boundaries defined along an ideal intended track. Through utilization of irrigation apparatus in accordance with the present invention, it is practical to accomplish irrigation of greater tracts of land than heretofore provided. Moreover, it is not necessary to provide specific guideways for each of the various movable powers of the irrigation system in order to control lateral movement of these systems over a particular land area. By appropriate control, the irrigation system of the present invention can be caused to move laterally and to pivot in such a manner that it will automatically track along a guide structure that is not straight or is irregularly curved. Accordingly, the present invention is well adapted to attain all of the objects and advantages hereinabove set forth, together with other advantages that will become apparent and obvious from a description of the apparatus itself. It will be understood that certain combinations and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the spirit and scope of the present invention.
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A linearly movable irrigation system, according to the present invention, may include a plurality of interconnected power driven irrigation spans supporting a water supply conduit, which sections are capable of moving over a land area and depositing a controlled amount of water thereon. At one extremity of the irrigation system may be provided a steerable and powered mover unit that accepts water from a water supply system and conducts it to the overhead irrigation pipe under sufficient pressure to cause proper distribution of water through sprinkler devices located along the length of the irrigation conduit. A power driven pump may be supported by the steerable mover unit in order to pressurize or provide boosting pressure for the water received from the water supply. The steerable mover unit is adapted to steerably move in proximity to an elongated reference which may be straight or curved as desired. The steerable mover unit is provided with means for sensing stresses and angular relationship of the irrigation spans relative to the steerable mover unit for providing control signals to the irrigation system that maintain stresses and angular misalignment of the system within an acceptable range. Each extremity of the irrigation system may move at different average speeds which are determined by the control signals for corrective relative movement. The extremities of the irrigation system may also move simultaneously at equal speeds or at different speeds to accomplish controlled movement during irrigation operations.
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RELATED APPLICATIONS
This patent application is a continuation-in-part application of U.S. patent application Ser. No. 09/015,729, filed Apr. 7, 1998, now U.S. Pat. No. 6,103,881 which is a continuation-in-part application of U.S. patent application Ser. No. 07/837,639 filed Feb. 14, 1992, now issued U.S. Pat. No.5,378,688, issuing Jan. 3, 1995, entitled “GnRH ANALOGS FOR DESTROYING GONADOTROPHS”, which is a continuation-in-part of U.S. patent application Ser. No. 07/314,653, filed Feb. 23, 1989 abandoned and also entitled “GnRH ANALOGS FOR DESTROYING GONADOTROPHS.” This patent application is also a continuation-in-part of three U.S. patent applications, Ser. Nos. 08/088,434, filed Jul. 7, 1993 08/094,250 filed Jul. 20, 1993 and 08/094,625 filed Jul. 20, 1993.
FIELD OF THE INVENTION
The present invention generally relates to methods for sterilizing animals and to methods for medically treating certain sex hormone related diseases such as, for example, cancer of the breast or prostate. More particularly, this invention relates to sterilization and medical treatment by means of chemical attack upon the pituitary gland.
BACKGROUND OF THE INVENTION
Considerable interest exists with respect to the subject of sterilization of animals. This is especially true of those concerned with veterinary medicine and animal husbandry, particularly as they relate to the subject of sterilization of domestic animals such as dogs, cats, cattle, sheep, horses, pigs, and the like. Various methods have been developed over the years to accomplish sterilization. For example, with respect to male cattle, the most widely used procedure for eliminating problems of sexual or aggressive behavior is sterilization through surgical castration. This is done in various ways, e.g., crushing the spermatic cord, retaining the testes in the inguinal ring, or use of a rubber band, placed around the neck of the scrotum, to cause sloughing off of the scrotum and testes. However most of these “mechanical” castration methods have proven to be undesirable in one respect or another; for example they (1) are traumatic, (2) introduce the danger of anesthesia, (3) are apt to produce infection, and (4) require trained personnel. Moreover, all such mechanical castration methods result in complete abolition of the testes and this of course implies complete removal of the anabolic effects of any steroids which are produced by the testes and which act as stimuli to growth and protein deposition.
These drawbacks have caused consideration of various alternative sterilization techniques such as the use of chemical sterilization agents. However, the use of chemical sterilization agents has its own set of advantages and disadvantages. On the positive side, chemical sterilization eliminates the stress and danger associated with mechanical castration. Chemical sterilization also has the added advantage of allowing for retention of certain anabolic effects resulting from a continued presence of low levels of circulating testosterone. This is especially valuable in the case of animals raised for human consumption since circulating testosterone promotes growth, efficiency of feed conversion and protein deposition. Unfortunately, there are several disadvantages associated with chemical sterilization. For example chemical sterilization is often temporary rather than permanent; it also sometimes produces extremely severe, and even fatal, side effects.
Many of these chemical sterilization methods have been aimed at regulation of luteinizing hormone produced at various stages of an animal's sexual development. For example, with respect to cattle it has been established that in the case of the infantile calf, luteinizing hormone is rarely discharged and testicular production of androgens is at low levels. On the other hand, in a prepubertal calf, or an adult bull, discharges of luteinizing hormone from the anterior pituitary occur more frequently and the testes produce considerably larger amounts of testosterone and other steroids. It is thought that these conditions result from the following factors: (1) decreases in the concentration of estradiol receptors in the hypothalamus, (2) concomitant increases in the concentration of estradiol receptors in the anterior pituitary, and (3) increases the number of gonadotropin-releasing hormone (GnRH) receptors in the anterior pituitary. This increase in GnRH receptors is generally regarded as a prerequisite for an animal to pass from the infantile stage to the prepubertal and mature stages of endocrine development. Hence, based upon these understandings of the hypothalamic-pituitary-testicular axis, several chemical methods have been proposed to modify given animals, e.g., a bull calf, in such a way that it never enters puberty, but still receives stimuli for growth and protein deposition through the anabolic effects of steroids produced by modified testes. In any event, most of the chemicals proposed for such sterilization purposes are hormones or hormone analogs. For example U.S. Pat. No. 4,444,759 teaches the use of a class of peptides analogous to GnRH (i.e., gonadotropin-releasing hormone, and particularly luteinizing hormone-releasing hormone) are capable of inhibiting release of gonadotropins by the pituitary gland and thereby inhibiting release of the steroidal hormones, estradiol, progesterone and testosterone. It should also be noted that the terms “GnRH” (gonadotropin-releasing hormone) and “LHRH” (luteinizing hormone-releasing hormone) are sometimes used interchangeably in the literature. For the purposes of describing the prior art both terms may be employed; however, for the purposes conveying the teachings of our patent disclosure, applicants prefer the term GnRH and will use it in describing their compounds.
Be that as it may, some prior art chemical sterilization procedures are specifically adopted to alter luteinizing hormone secretion before the animal has attained the age of puberty. This is not surprising since the role of luteinizing hormone in sexual maturation is well known. Luteinizing hormone is a gonadotropic hormone found in the anterior lobe of the pituitary gland and, in male animals, it is known to stimulate the interstitial cells of the testes to secrete testosterone (see generally, The Merck Index, 8th edition, p. 560 (1968), Encyclopedia of Chemical Technology, Vol. 7, pp. 487-488 (1951)).
One approach has been to use certain chemicals to produce antibodies in an animal which exhibit cross-reactivity with the gonadotropins produced by the animal's pituitary gland. It is generally thought that with such early antigenic stimulation, formation of antibodies is more continuously stimulated by the release of endogenous hormones and that early immunization with such luteinizing hormone deters the maturation of the gonads and adnexal glands. This, in turn, is thought to inhibit spermatogenesis at the spermatogonial level. For example, U.S. Pat. No. 4,691,006 teaches injection of a compound having an amino acid sequence of at least 20 units for purposes of eliciting formation of antibodies which exhibit cross-reactivity with the gonadotropins produced by the animal's pituitary. With early antigenic stimulation of this kind, the formation of such antibodies is more continuously stimulated by release of endogenous hormones. Early immunization with such luteinizing hormone also deters the maturation of the gonads and adnexal glands. However, the art has also recognized that early immunization of this kind may tend to make the interstitial tissues fibroblastic. It has also been found that such early stimulation of the immunologic system leads to development of a high titered antiserum to luteinizing hormone which remains at relatively high levels. Nonetheless, periodic boosters of such compounds are often necessary even for adult animals sterilized before puberty in order to maintain high levels of the neutralizing antibodies.
Similarly, luteinizing hormone has been administered to animals after they have attained the age of puberty in order to atrophy their reproductive organs and to cause a decrease in libido (see generally, M. Tallau and K. A. Laurence, Fertility and Sterility, Vol. 22, No. 2, February 1971, pp. 113-118, M. H. Pineda, D. C. Lueker, L. C. Faulkner and M. L. Hopwood, Proceedings of the Society for Experimental Biology and Medicine, Vol. 125, No. 3, July 1967, pp. 665-668, and S. K. Quadri, L. H. Harbers, and H. G. Spies, Proc. Soc. Exp. Biol. Med., Vol. 123, pp. 809-814 (1966). Such treatments also impair spermatogenesis in noncastrated adult male animals by interruption of the spermatogenic cycle.
Other chemical sterilization agents have been specifically designed for use on female animals. For example, it is well known that certain antigens will produce an antiserum against a requisite estrogen. This is accomplished by first making an antigen and then injecting said antigen into an animal for purposes of antiserum production. The animal is then bled to recover the antiserum. Any female animal of the same species as the host animal may then be injected with the antiserum at the proper time prior to ovulation and the injected antiserum will cause temporary sterilization of that animal.
Other methods of chemical sterilization have been based upon direct chemical attack upon certain cells of the pituitary itself (as opposed to chemical attacks upon the hormone products of such cells) with a view toward permanently destroying such cells. Again, this approach is suggested by the fact that follicle stimulating hormone (FSH) and luteinizing hormone (LH) (sometimes referred to as gonadotropins or gonadotropic hormones) are released by the pituitary gland to regulate functioning of the gonads to produce testosterone in the testes and progesterone and estrogen in the ovaries. They also regulate the production and maturation of gametes.
Several chemical agents have been proposed for such purposes. However, it has been found that most chemical agents which are in fact capable of destroying the gonadotrophs of an animal's anterior pituitary gland also tend to produce extremely toxic side effects which can severely weaken, and sometimes kill, the treated animal. Hence, with respect to the general subject of chemical sterilization, it can be said that any chemical capable of producing sterilization without, or with minimal, toxic side effects would be of great value in the fields of animal husbandry, veterinary medicine and wildlife control.
To date, perhaps the closest concepts and/or compounds to those described in this patent disclosure are found in a publication by Myers, D. A., Murdock, W. J. and Villemez, C. L., entitled Protein-Peptide Conjugation By A Two-Phase Reaction: Biochem. J., 227:1 pg. 343 (1985). This reference teaches a sterilization procedure employing a GnRH analog comparable to that utilized by applicant in one of his more preferred GnRH/toxin conjugate compounds, namely one based upon a GnRH/diphtheria toxin conjugate. However, there are some very pronounced differences in the toxin portions of the respective molecules. These differences reside in the fact that different parts or portions of the diphtheria toxin are employed in the respective resulting compounds. More specifically, the conjugate reported by Myers et al. utilized only the toxin domain of the diphtheria toxin molecule while applicant's diphtheria toxins are characterized by their possession of the membrane translocation domain of this toxin as well as the toxic domain. The details and significance of these molecular differences are important to this patent disclosure and will be discussed at greater length in subsequent parts of this patent disclosure.
However, before leaving this discussion of the GnRH/diphtheria conjugate aspect of the prior art, it also should be noted that in addition to the article by Myers et al. noted above, Myers, on another occasion, published additional information concerning his diphtheria toxin-GnRH analog conjugate. This was done in his Ph.D. thesis at the University of Wyoming in 1987, entitled: “Hybrid toxins: An approach to cell specific toxicity.” This thesis contains basically the same information as the above-noted 1985 publication, but—of course—in much greater detail. For example, the thesis includes further information on the biological activity of the Myers conjugate. A second part of this thesis addresses modifications of Myers' diphtheria toxin in a manner similar to that described above, but using further information published by Colombatti et al. in the Journal of Biological Chemistry 261:3030 (1986).
Another reference of possible interest in this regard was recently published in the INTERNATIONAL JOURNAL OF PHARMACOLOGY 76: R5-R8 by Singh et al. entitled “Controlled release of LHRH-DT from bioerodible hydrogel microspheres.” Generally speaking, it teaches that a natural GnRH/diphtheria toxin can be used as a vaccine. In this case the LHRH-DT molecule induces production of antibodies to GnRH which then serve to inactivate endogenous LHRH in the circulation. Without the endogenous LHRH, there is no stimulation of the anterior pituitary gland to secrete LH and the gonads will cease functioning. However, as the antibody titers fall, endogenous GnRH will again stimulate the anterior pituitary gland, LH secretion and gonadal function will return. Here again, those skilled in this art will appreciate that this is an entirely different approach from the “direct chemical attack on the pituitary gland” approach taught in this patent disclosure. That is to say that—unlike Singh's antibody production approach—applicant's conjugate will not generate antibodies to GnRH and no neutralization of endogenous GnRH will occur. Instead, with applicant's approach, the cells in the anterior pituitary gland which are activated by GnRH will be destroyed by direct chemical attack thereon. Moreover, this attack results in permanent, rather than temporary sterility.
However, before going on to these details, it also should be noted that knowledge of the above noted sex hormone functions has produced several advances in the field of human medicine as well. For example, the potential for achieving chemical castration (rather than “surgical” castration) with certain luteinizing hormone-releasing hormone (LHRH) analogs has been reported (see for example, Javadpour, N., Luteinizing Hormone-Releasing Hormone (LHRH) in Disseminated Prostatic Cancer; 1M, Vol. 9, No. 11, November 1988). Table I below gives the structure of LHRH and the structure of certain analogs (e.g., Goserelin, Leuprolide, Buserelin and Nafarelin) of LHRH which are capable of temporarily suppressing luteinizing hormone secretion and thereby suppressing the gonads. As a consequence, these LHRH analogs have come to be regarded as a promising new class of agents for the treatment of various host-dependent diseases, especially prostatic cancer. In referring to Table I, it first should be noted that LHRH has a decapeptide structure and that substitution of certain amino acids in the sixth and tenth positions of the LHRH produce analogs which render agonists that are up to 100 times more potent than the parent LHRH compound (hence these compounds are often referred to as “superagonists”). The structures of LHRH and the most commonly known LHRH superagonists are listed below.
STRUCTURES OF LHRH AND SOME SUPERAGONISTS
(Superagonists have substitutions at
positions 6 and 10)
LHRH: pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH 2
1 2 3 4 5 6 7 8 9 10
SUPERAGONISTS:
Name
Subs. at 6
Subs. at 10
Terminator
Goserelin:
D-Ser(tBu)
AzaGly
Amide
Leuprolide:
D-Leu
des-Gly
Ethylamide
Buserelin:
D-Ser(tBu)
des-Gly
Ethylamide
Nafarelin:
D-2-NaphthylAla
None
Amide
While these compounds represent the most promising means for palliative therapy because of their relative lack of side effects, they are particularly expensive and must be administered repeatedly. Even the newest formulations utilizing polymer encapsulated drug or other depot forms will require at least monthly administration. Improved depot forms also are presently in development, but they too are likely to be equally expensive and they too will probably require monthly administration. In response to these many drawbacks, applicants have developed a class of compounds which is capable of producing safe, inexpensive, chemical castration as an alternative to surgical castration. Such drugs also greatly simplify therapy of the generally elderly patients with prostate cancer, and could eliminate the need for surgical castration (still preferred by many urologists) as well as provide a medical alternative to oophorectomy in females with advanced breast cancer. Moreover, as a model system, the ability to eliminate pituitary gonadotrophs in vivo, which are regulated by GnRH receptors in response to ligand stimulation in a predictable fashion, is a highly appealing first step toward the more complex use of toxins conjugated to antibodies to eliminate tumor targets. Hence, use of applicants' compounds generally will fall into two major areas of use. The first is sterilization of mammals of all types; the second is chemical castration of mammals in general, and human beings in particular, for purposes of treating breast or prostate cancer by ablating those pituitary cells, namely gonadotrophs, responsible for LH secretion.
SUMMARY OF THE INVENTION
The present invention provides a group of GnRH/toxin conjugate compounds and processes for using them to sterilize mammals (animals and humans) and/or for treating certain sex hormone related diseases such as cancer of the prostate or cancer of the breast. The active parts of these compounds or agents may be referred to as “toxic compounds”, (“T”) or “toxins” for the purposes of this patent disclosure without changing the intended scope of the herein described compounds and/or processes. In any event, the most effective, and hence most preferred, of these toxin compounds will include: diphtheria toxin, ricin toxin, abrin toxin, pseudomonas exotoxin, shiga toxin, α-amanitin, pokeweed antiviral protein (PAP), ribosome inhibiting proteins (RIP), especially the ribosome inhibiting proteins of barley, wheat, flax, corn, rye, gelonin, abrin, modeccin and certain cytotoxic chemicals such as, for example, melphalan, methotrexate, nitrogen mustard, doxorubicin and daunomycin. All of these toxins are characterized by their inability, in their own right, to chemically attack the gonadotropin-secreting cells of the anterior pituitary gland as well as by their concomitant ability to chemically attack gonadotropin-secreting cells when conjugated with GnRH molecules (and GnRH analogue molecules) according to the teachings of this patent disclosure.
Some of these toxins (e.g., bacterial toxins and certain plant toxins) can be characterized by whether or not a “whole” molecule of a given toxin is employed. For the purposes of this patent disclosure the term “whole” may be taken to mean that the molecule has at least a toxic domain, a translocational domain and a cell binding domain. If, however, one or more of these domains are removed from a “whole” toxin molecule, then the resulting molecule will be characterized as a “modified” toxin or “modified” molecule of that toxin. TABLE I below gives some representative “whole” and “modified” toxins. Some of these toxin types (e.g., bacterial and plant toxins) also can be further characterized by their possession of so-called “A-chain” and “B-chain” groups in their molecular structures. It also should be noted that the toxic domain is often referred to as the “A-chain” portion of the toxin molecule while the toxic domain, translocation domain and cell-binding domain are often collectively referred to as the “whole” toxin or the A-chain plus the B-chain molecules. For example, such further classifications could be made according to the attributes, categories and molecular sizes noted in TABLE I below (wherein the letters A and B represent the presence of A-chains or B-chains and the letter K designates the symbol (“kilodalton” used to designate molecular sizes of such molecules):
TABLE I
Single Chain Toxins
Pokeweed antiviral protein
Gelonin ribosome-inhibiting protein (RIP)
Wheat RIP
Barley RIP
Corn RIP
Rye RIP
Flax RIP
Bacterial Toxins
Diphtheria toxin (whole) having a toxic domain, a
translocation domain and a cell-binding domain =
62K
Diphtheria toxin (modified) having a toxic domain
and a translocation domain = 45K
Pseudomonas exotoxin (whole) having a toxic
domain, a translocation domain and a cell-binding
domain = 66K
Pseudomonas exotoxin (modified) having a toxic
domain and a translocation domain = 40K
Shiga toxin (whole) having a toxic domain, a
translocation domain and a cell binding domain =
68K
Shiga toxin (modified) having a toxic domain =
30K
Plant Toxins
Ricin A + B (whole) = 62K
Ricin A = 30K
Abrin A + B = 62K
Abrin A = 30K
Modeccin A + B = 56K
Modeccin A = 26K
Small Chemical Toxins
Melphalan
Methotrexate
Nitrogen Mustard
Daunomycin
Doxorubicin
Applicants have also found that of all the possible toxin molecules noted above, the bacterial and plant toxins having both a toxic domain and a translocation domain (which may also be referred to as B-chain “parts”, “shortened B-chain, amino acid sequences”, etc.), but not a cell-binding domain are the most effective—and hence the most preferred—conjugate compounds for applicant's sterilization purposes. The procedures by which cell-binding domains can be deleted are of course well known to this art and need not be discussed in any great detail.
Moreover, in considering the general subject of transmembrane transport proteins, as they relate to this invention, applicants would also point out that there are a number of viral proteins, for example, which function in ways similar to the “translocation domain” functions of diphtheria toxin, ricin, and of Pseudomonas toxin. These include the Sendai virus HN and F glycoproteins, and the Adenovirus penton proteins along with similar fusogenic proteins of Semliki Forest virus. Also, lipophilic polylysines, such as poly(l-lysine) conjugated to glutarylphosphatidylethanolamine can function in this way. Consequently, those skilled in the art will appreciate that the transmembrane transport of applicants' conjugates can be enhanced by inclusion of any such fusogenic moieties into our GnRH-toxin conjugates.
However, regardless of such concerns for the presence, identity, and/or size of B-chains in certain toxin molecules, applicants have found that all of the herein described sterilization agents can be most effectively delivered to the pituitary gland if they are chemically conjugated with various peptide hormone molecules such as certain analogs of gonadotropin-releasing hormone, GnRH. Again, this conjugation is necessary because, for the most part, the above toxins, by themselves, are not capable of binding with cell membranes in general. That is to say that applicants have found that it is only when a GnRH analog of the type described herein is linked to a toxin of the types noted above does that toxin become capable of binding to cell membranes, and then only to those cells whose membranes contain receptors for GnRH (i.e., gonadotrophs in the anterior pituitary gland). Other less preferred, but still operative peptide hormone molecules (other than applicant's preferred gonadotropin-releasing hormone analogues) to which the herein disclosed toxins could be so conjugated for applicant's sterilization purposes include: human chorionic gonadotropin, equine chorionic gonadotropin, luteinizing hormone and follicle-stimulating hormone.
At this point, it should again be emphasized that for the purposes of this patent disclosure, the term gonadotropin-releasing hormone will usually be abbreviated as “GnRH ” and that, for the most part, certain hereinafter described analogs of GnRH are generally more effective carrier peptide hormone molecules for the practice of this invention than the fundamental or parent GnRH molecule. In their most generalized sense, these analogs will be abbreviated as “GnRH-A”, with the “A” designating that the resulting compound is an analog, “A” of the fundamental GnRH molecule. Again, any general toxin compound which is conjugated with a GnRH-A molecule will be abbreviated by the letter “T” for toxin. Thus, the abbreviation for a generalized conjugate of a GnRH-A analog and a toxin will be “GnRH-A-T”.
In the case of GnRH-A carrier peptide molecules, the linking or coupling of the GnRH-A molecule and the T molecule is preferably carried out at the 6 position of the GnRH-A molecule. This modification may include use of a linkage using a heterobifunctional reagent “Y” which will be described in much more detail in subsequent portions of this patent disclosure. That is to say that the most preferable technique for production of the resulting GnRH-A-T conjugate molecule will involve modification of the 6 position of the fundamental GnRH molecule. In other words, amino acid substitutions at the 6 position of the fundamental GnRH molecule will yield analogs with particularly high affinities for GnRH receptors on cells of the pituitary gland and thereby providing an improved means for introducing the toxin into the targeted cells.
The most preferred amino acids for substitution at the 6-position will include lysine, D-lysine, aspartic acid, D-aspartic acid, glutamic acid, D-glutamic acid, cysteine, D-cysteine, ornithine, D-ornithine, tyrosine, D-tyrosine as well as other amino acids having suitable side-chain functional groups such as, for example, amino groups, carboxylic groups, hydroxyl groups or sulfhydryl groups. Similarly the 10 position of the fundamental GnRH molecule can be modified to produce other analog variations useful for applicant's purposes. The substituents most preferred for this purpose will include Gly-NH 2 , ethylamide and AzA-Gly-NH 2 .
Heterobifunctional reagent Y is, most preferably, used to link a GnRH-A group or moiety to a toxic group or moiety T. Most preferably such toxic groups T and their associated GnRH-A carrier peptide molecules will be covalently linked by a linking or coupling agent selected from the group consisting of 2-iminothiolane, N-succinimidyl-3-(2-pyridyldithio) proprionate (SPDP), 4-succinimidyloxycarbonyl-α-(2-pyridyldithio)-toluene (SMPT), m-maleimidobenzoyl-N-hydroxysuccinimide -ester (MBS), N-succinimidyl(4-iodoacetyl)aminobenzoate (SIAB), succinimidyl 4-(p-maleimidophenyl)butyrate (SMPB), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), bis-diazobenzidine and glutaraldehyde.
Given all of these structural concerns, a generalized chemical structural diagram of an amino acid sequence of a GnRH molecule and of a group of highly preferred resulting GnRH-A-T carrier peptide molecules for the practice of this invention could be depicted as follows:
wherein X is an amino acid, Y is a linking group, Z is a chemical substituent selected from the group consisting of Gly-NH 2 , ethylamide and Aza-Gly-NH 2 and T is a toxin group selected from the group consisting of the plant toxins: ricin, modeccin, abrin, pokeweed anti-viral protein, α-amanitin, gelonin ribosome inhibiting protein (“RIP”) barley RIP, wheat RIP, corn RIP, rye RIP and flax RIP; the bacterial toxins selected from the group consisting of: of diphtheria toxin, pseudomonas exotoxin and shiga toxin (and especially those bacterial toxins having a toxic domain and a translocation domain) and the chemical toxins selected from the group consisting of: melphalan, methotrexate, nitrogen mustard, doxorubicin and daunomycin.
Those skilled in this art will appreciate that some specific compounds falling within the above generalized structure are often referred to as “D-Lys 6 -GnRH.” That is, in normal peptide nomenclature, the reference to D-Lys 6 before the GnRH indicates that the normal 6-position amino acid group of the GnRH molecule (i.e., a “Gly” group), has been replaced by lysine. Thus, the X, i.e., the 6-position X amino acid would in fact be lysine. Hence, the most general GnRH-A amino acid sequence could be depicted as follows:
That is to say that, applicant's molecules will be further characterized by having a generalized amino acid in the X (or 6) position. Preferably, this amino acid will be selected from the group consisting of: lysine, D-lysine, ornithine, D-ornithine, glutamic acid, D-glutamic acid, aspartic acid, D-aspartic acid, cysteine, D-cysteine, tyrosine and D-tyrosine.
Within the possibilities implicit in the general structure, a particularly preferred GnRH analog would be:
pyroGlu-His-Trp-Ser-Tyr-D-Lys-Leu-Arg-Pro-ethylamide (Eq. III)
This molecule also could be referred to as [D-Lys 6 -des-Gly 10 ]-GnRH-ethylamide and, regardless of nomenclature, it represents one of applicant's most preferred GnRH-A molecules.
The presence of the Y component of the most general structure (i.e., Equation I) is optional—but highly preferred. Again, if used, such Y groups are most preferably selected from the group consisting of: 2-iminothiolane, N-succinimidyl-3-(2-pyridyldithio) proprionate (SPDP), 4-succinimidyloxycarbonyl-α-(2-pyridyldithio)-toluene (SMPT), m-maleimidobenzoyl-N-hydroxysuccinimide ester (MBS), N-succinimidyl(4-iodoacetyl)aminobenzoate (SIAB), succinimidyl 4-(p-maleimidophenyl)butyrate (SMPB), 1-ethyl-3-(3-dimethylaminopropyl)carbodimide (EDC), bis-diazobenzidine and glutaraldehyde.
The most preferred forms of these compounds will have an amino group, a carboxylic group and/or a sulfhydryl group, to aid in the Y group's performance of this GnRH-A to T linking function. In other words the T group most preferably will be attached to a GnRH-A molecule by means of an amino, carboxylic or sulfhydryl group of 2-iminothiolane, N-succinimidyl-3-(2-pyridyldithio) proprionate (SPDP), 4-succinimidyloxycarbonyl-α-(2-pyridyldithio)-toluene (SMPT), m-maleimidobenzoyl-N-hydroxysuccinimide ester (MBS), N-succinimidyl(4-iodoacetyl)aminobenzoate (SIAB), succinimidyl 4-(p-maleimidophenyl)butyrate (SMPB), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), bis-diazobenzidine and glutaraldehyde. Similarly, the Y group most preferably will be attached to the X group at the site of an amino group, a carboxylic group, a sulfhydryl group or a hydroxyl group of whatever amino acid group is employed at the 6-position of applicant's GnRH-A molecule.
As previously noted, the T group represents a toxin group which, first and foremost, is capable of chemically attacking the gonadotrophs of the pituitary gland when conjugated to the carrier peptide (GnRH-A) molecules described in this patent disclosure. Again, as seen in TABLE I, certain toxins T such as the bacterial toxins and plant toxins such as ricin, abrin and modeccin, can be composed of a toxic domain (also referred to as an A-chain), a translocation domain and a cell-binding domain (the latter two domains are sometimes referred to as the B-chain) and that applicants believe that, in general, use of toxins having a toxic domain plus a translocation domain, but not a cell-binding domain, will give more effective results than use of toxins having only a toxic domain (A-chain) only or a toxic domain, translocation domain and cell-binding domain (also referred to as whole toxin or A-chain plus B-chain). The ribosome-inhibiting proteins (RIP) also will be effective toxins, but here again, only after conjugating them to a GnRH analog. That is to say that by themselves, they are not toxic since they do not contain a cell membrane binding domain. However, if conjugated to one of applicant's GnRH analogs, the resulting conjugate molecule can interact with GnRH receptors and gain entry into the pituitary cell, thereby preventing protein synthesis and ultimately causing the desired effect—cell death. The RIPs of barley, corn, wheat, rye and flax will be especially useful for this purpose. Pokeweed antiviral protein is similar in nature to the RIPs noted above and hence can also be employed as the toxin T. The bacterial toxins, diphtheria toxin, pseudomonas exotoxin and shiga toxin are especially preferred. Again, these bacterial toxins are originally comprised of a toxic domain, a translocation domain and a cell-binding domain, but applicants have found that in general those having their toxic domain plus their translocation domain are generally more effective than those bacterial toxin having only a toxic domain or those comprised of the whole molecule. Chemical toxins selected from the group consisting of melphalan, methotrexate, nitrogen mustard, doxorubicin and daunomycin are particularly preferred. Obviously, A-chain and B-chain considerations will not be applicable to “chemical” toxins because they are not made up of amino acid groups such as those found in bacterial or plant toxins.
It should, however, also be noted that regardless of whether the toxin T is comprised of an A-chain, an A-chain plus a portion of a B-chain, or a chemical molecule which does not contain an amino acid sequence, it is preferably attached to the GnRH portion of the overall conjugate molecule via a linking Y compound selected from the group consisting of: 2-iminothiolane, N-succinimidyl-3-(2-pyridyl-dithio) proprionate (SPDP), 4-succinimidyloxycarbonyl-α-methyl-α-(2-pyridyldithio)-toluene (SMPT), m-maleimidoacetyl)aminobenzoate (SIAB), succinimidyl 4-(p-maleimidophenyl)butyrate (SMPB), 1-ethyl-3-(3-di-methylaminopropyl)carbodiimide (EDC), bis-diazobenzidine and/or glutaraldehyde.
It should again be emphasized that one particularly important aspect of the herein disclosed invention is based upon applicant's finding that those appropriate (i.e., bacterial or plant) toxin moieties having both an A-chain and at least a portion of a B-chain, but not all of the B-chain, in the overall GnRH/toxin conjugate molecules are especially well suited to the herein described sterilization functions. This preference for the presence of a portion of a given toxin's B-chain in the overall conjugate molecule is important to this patent disclosure for several reasons. First, applicant's B-chain-containing compounds have proven to be generally much more effective sterilization agents than those amino acid containing toxins having only an “A-chain” portion. Moreover, such amino acid containing toxins also tend to be less toxic in their side effects.
This difference also serves to distinguish applicant's invention from those other sterilization methods using GnRH molecules in their own right or from those employing other GnRH/toxin conjugate compounds. For example, the previously noted GnRH/diphtheria toxin used in the process reported by Myers et al. utilized only the A-chain portion of the diphtheria toxin molecule. That is to say that diphtheria toxin is a 62 kilodalton protein, composed of a 21 kilodalton A chain and a 37 kilodalton B chain linked together by disulfide bonds. Myers et al, in effect, confirmed that an A-chain, diphtheria toxin can serve to inhibit protein synthesis in a cell by catalyzing the ADP-ribosylation of a cell constituent known as “elongation factor 2.” Again, in the absence of protein synthesis, a cell cannot function and eventually dies.
This follows from the fact that a cell's elongation factor 2 is located in its cytoplasm, and a toxin such as diphtheria toxin must first gain entry into the cytoplasm in order for its toxicity to be manifested. Thus, the most preferred forms of toxins for the practice of this invention (e.g., use of diphtheria toxin in applicant's resulting GnRH-A-T conjugates) will have a toxin molecule which includes the toxic domain (for cytotoxicity) and the translocation domain that increases the ability of the overall molecule to cross cell membranes. That is to say that this translocation domain “portion” serves to greatly assists entry of the toxic domain portion of the toxin into a cell's cytoplasm and thus increases the potency of the resulting conjugate as a sterilization agent.
Applicant has, however, found that the presence of the translocation domain of a toxin such as diphtheria toxin greatly enhances the sterilization efficacy and/or nontoxicity of GnRH-A-T conjugates of the type disclosed in this patent application. Again, use of an entire toxin molecule is not preferred for applicant's purposes. That is to say that in those cases where an overall toxin molecule contains a toxic domain, a translocation domain and a cell-binding domain, applicant prefers to delete the cell-binding domain.
For example, a diphtheria B chain has two parts, a translocation domain and a cell-binding domain. These two portions are a carboxyl terminal of 8 kilodaltons which contains a cell surface binding domain that permits diphtheria toxin to attach to nearly all mammalian cells to which it is exposed and an amino terminal of 21 kilodaltons which contains several hydrophobic regions that can insert into a membrane at a low pH. The cell-binding domain of the diphtheria's B-chain is preferably cleaved away.
As previously noted, in some of the most preferred conjugate molecules, applicant has provided a diphtheria toxin portion comprised of a toxic domain and a translocation domain and additionally comprising a “spacer” group which most preferably ends in a cysteine residue. This arrangement has the advantage of providing a free sulfhydryl group that can be used to attach the toxin molecule to the GnRH analog in such a way as to minimize interference with the desired enzymatic activity (i.e., performance of the toxicity function of the toxic domain).
Again, applicant has discovered that the analogue of the GnRH molecule having the following structure:
pyroGlu-His-Trp-Ser-Tyr-D-Lys-Leu-Arg-Pro-ethylamide
is particularly efficacious for conjugation and delivery of a diphtheria toxin comprised of an A-chain and a part or fragment of the diphtheria toxin molecule's B-chain amino acid sequence. As previously noted, this molecule could be referred to as the [D-Lys 6 -des-Gly 10 ]-GnRH-ethylamide analogue of the GnRH molecule. Regardless of nomenclature, applicant has found this to be the most effective (and, hence, the most preferred) GnRH analogue/diphtheria toxin conjugate for applicant's sterilization methods. And, as in the more general cases noted in the previous discussion of the nature of the 6 position “X” group of the more general molecular structures, lysine, D-lysine, ornithine, D-ornithine, glutamic acid, D-glutamic acid, aspartic acid, D-aspartic acid, cysteine, D-cysteine, tyrosine and D-tyrosine could each be substituted in the amino acid #6 position of this most preferred [D-Lys 6 -des-Gly 10 ]-GnRH ethylamide/diphtheria molecule. However, it also should be noted that the analogs resulting from these changes at the 6 position are generally somewhat less preferred, but still useful, for applicant's general process.
The resulting conjugates are specifically targeted to the gonadotropin-secreting cells of the anterior pituitary gland. Indeed they are the only cells to which the gonadotropin-releasing hormone portion of applicant's conjugates will bind. Hence, the toxic compounds, bound to an analog of gonadotropin-releasing hormone, serve to permanently destroy a subpopulation of the anterior pituitary cells and thereby eliminate the gland's ability to secrete gonadotropins. Applicant has termed this mechanism “direct chemical attack” to contrast it with the use of certain GnRH molecules to elicit an immune response to the gonadotropin products of the pituitary. This direct chemical attack upon the pituitary gland, in turn, causes the animal's gonads to atrophy and lose their ability to function for reproductive purposes. In other words, without functioning gonadotrophs, an animal is not able to secrete luteinizing hormone (LH) and follicle-stimulating hormone (FSH) and thus is rendered sterile. Applicants have postulated that the compounds of this patent disclosure inhibit synthesis of LH, and presumably other proteins made by gonadotrophs, because they tend to inhibit all protein synthesis once these compounds gain entry into the pituitary cells.
Consequently, these compounds have great potential utility in human medicine as well as in veterinary medicine. This follows from the fact that there are several important biological reasons for employing castration and antifertility drugs in humans. For example, breast and prostate cancers are but two examples of sex steroid-dependent tumors which respond to such hormonal manipulation. At present, the only reliable way to inhibit steroid-dependent tumor growth is through administration of counter-regulatory hormones (e.g., DES in prostate cancer), sex-steroid hormone binding inhibitors (e.g., tamoxifen in breast cancer) or surgical castration. Thus the potential medical uses of such chemical castration compounds are vast and varied. For example, prostate cancer remains an important cause of cancer deaths and represents the second leading cancer of males. The present palliative treatment for advanced prostate cancer cases involves reduction of serum testosterone/DHT levels through use of surgical castration. It should also be noted that for purposes of disease and/or fertility control, especially in humans, it may be desirable to use applicants' compounds to ablate pituitary gonadotrophs in conjunction with other modes of treatment. For example, it is anticipated that chronic administration of progestins and estrogens to females and androgens to males might be necessary to prevent loss of secondary sex characteristics, behavior and osteoporosis. However, through judicious use of the herein disclosed compounds, especially in combination with appropriately administered sex steroids, desirable antifertility effects can be achieved. Another area of application in human medicine is treatment of endometriosis. This condition, which produces painful growth of endometrial tissue in the female peritoneum and pelvis also responds to inhibition of sex steroid synthesis. Those skilled in this art will also appreciate that the herein disclosed compounds could be used to partially reduce sex-steroid secretions, and thus reduce or eliminate certain hormone related behavior problems while retaining improved growth stimulation.
The dose/time adjustments associated with the use of these compounds can vary considerably; however, these compounds are preferably administered by injection into a mammal in concentrations of from about 0.1 to about 10 milligrams per kilogram of the mammal's body weight. Sterilization may be accomplished with as few as one injection; but multiple treatments (e.g., based upon concentrations of from about 0.03 milligrams once every 4 days to about 1 milligram per kilogram of body weight for 20 days) are alternative sterilization schemes. Furthermore, as sterilization agents, the compounds of this patent disclosure can be used before or after puberty. They too are especially useful in those areas of animal husbandry where the anabolic benefits of non-surgical sterilization techniques can contribute to meat production and/or quality. In one preferred embodiment of this invention the compounds of this invention are administered to male cattle between the ages of about 8 weeks and 20 weeks at least once and in a concentration of from about 0.1 to about 10 milligrams per kilogram of the animal's body weight.
The toxic moieties T of the herein disclosed compounds are obtainable from both natural and synthetic sources. For example, pokeweed antiviral protein can be isolated from leaves of pokeweed plants and purified by gel filtration chromatography. It can then be, by way of example, conjugated to D-Lys 6 -desGly 10 ]-GnRH-ethylamide via the amino group on the lysine and through a sulfhydryl group introduced into the pokeweed antiviral protein by a heterobifunctional reagent. In any event, one of the chief advantages of these compounds is their ability to produce permanent sterilization without strong toxic side effects. Hence these compounds may be used on mammals such as human beings, domestic animals, pets or wild animals. Moreover, they can be administered as a single injection which can induce permanent and irreversible sterility in both male and female mammals. However, an alternative approach to achieve sterilization is through multiple injections at lower dosages than those employed in a single treatment or by slow release implants (i.e., biodegradable formulations).
Applicants also have postulated that the “B-chain” portion of their toxic moieties are important not only for binding to cell surfaces, but for trans-membrane translocation of their A-chain. This was particularly demonstrated for the A-chain of Diphtheria toxin, Ricin and Pseudomonas exotoxin. To this end, applicants prepared conjugates of GnRH-A to A and B chains of Diphtheria toxin as well as to a modified A-B chain which was genetically engineered to eliminate the carboxy terminal binding portion of the B-chain. These conjugates were shown to bind to pituitary cell GnRH receptors. They also were found to possess enhanced toxicity over A-chain conjugates based on improved trans-membrane transport characteristics. Given this, those skilled in the art will appreciate that numerous genetic and chemical modifications of B-chains should allow further exploitation of this approach. That is to say that, by such methods, it is possible to generate a whole series of conjugates that can be characterized as GnRH-A-A/B, GnRH-A-A, GnRH-A-A plus GnRH-B, all of which could enhance the findings described herein by simultaneous delivery of membrane active B-chains with the herein described GnRH-A-T conjugates.
Yet a further aspect of the present invention is directed to the use of bioengineered proteins conjugated with GnRH for use in regulating hormone related diseases to treat cancer, to achieve temporary and/or permanent sterilization of animals, and/or to inactivate gonadotrophs. Bioengineered or recombinant proteins, and specifically proteins having toxic moieties, offer the advantage of improved homogeneity, as compared to toxins that may be derived from other natural sources. Indeed, by using bioengineered and/or recombinant proteins having desirable cell-toxic attributes, it is believed that reduced costs of manufacture can be achieved due to the elimination of any extraction and purification procedures that would otherwise be required for recovering proteins from natural sources. In one particular aspect of the present invention, the recombinant pokeweed antiviral protein is produced and utilized which differs slightly from natural pokeweed proteins. The present inventors believe that the recombinant proteins produced by Rajamohan et al., specifically a recombinant pokeweed antiviral protein, has particular use in the present invention. Such recombinant pokeweed antiviral protein has a molecular weight of 33 kDa whereas the natural protein has a molecular weight of approximately 29 kDa. Thus, one aspect of the present invention involves the use of a hormone toxin conjugate comprised of a peptide hormone capable of binding to a GnRH receptor and at least one recombinant protein capable of inhibition of protein biosynthesis. Such recombinant proteins include, but are not limited to recombinant pokeweed antiviral protein.
Yet a further embodiment of the present invention relates to the use of a particular linking agent, namely N-[-maleinidobutyrloxy]sulfosuccinimide ester (Sulfo-GMBS).
In another embodiment, an SH group is introduced into dLys6-GnRH through the use of 2-IT, the advantage being increased solubility of the modified peptide.
DESCRIPTION OF DRAWINGS
FIGS. 1A and 1B respectively depict the results of GnRH induced secretion of LH based upon a single injection of a GnRH-A-T compound and the results of GnRH induced secretion of LH based upon 4 injections of a GnRH-A-T compound.
FIG. 2 indicates inactivation of certain grain hemitoxins (wheat hemitoxin and barley hemitoxin) by SPDP conjugation.
FIG. 3 depicts the results of a SDS-PAGE analysis of carbodiimide conjugated hemitoxins.
FIG. 4 shows the inhibition of 2-iminothiolane-conjugated barley hemitoxin.
FIG. 4A shows. SDS-PAGE analysis of barley hemitoxin after conjugation to [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide using 2-iminothiolane.
FIG. 5 shows binding curves indicating the ability of [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide toxin conjugates to bind to pituitary receptors.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
One of the chief objects of this invention is to provide a class of compounds which will allow safe, inexpensive, chemical castration. As such, applicants' compounds represent an alternative to surgical castration as well as to surgery for treatment of diseases such as breast cancer or certain sex hormone related prostate cancers. In order to better define this class of compounds, Applicants conducted studies on various linking technologies as they apply to numerous toxin candidates. These studies resulted in the herein disclosed group of conjugate compounds. In general these compounds display good gonadotroph membrane binding characteristics along with retention of toxin activity.
In general, the sterilization activity of the compounds of this patent disclosure was tested in receptor binding assays (to be sure a given conjugate was still capable of interacting with the GnRH receptor cells of the pituitary), in a cell-free translation system (to insure that the toxic protein maintained its toxicity), in cell culture systems (to determine if a given toxic conjugate is capable of inhibiting synthesis of LH), and in test animals (to determine if sterility was induced). For example, one of the more effective of these sterilization agents was a [D-Lys 6 -des-Gly 10 ]-GnRH-ethylamide which was conjugated to pokeweed antiviral protein using carbodiimide as the “linkage” group Y between the carrier protein molecule and the toxin moiety.
Again, a distinct advantage of each of the sterilization agents of this invention, and pokeweed antiviral protein in particular, is that they have an extremely limited ability to enter cells in an animal's body unless they are first conjugated to a carrier such as gonadotropin-releasing hormone. Such conjugation was accomplished in several ways. By way of example, pokeweed antiviral protein can be conjugated to a [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide molecule via the ε-amino group on the D-lysine to a sulfhydryl group on the pokeweed antiviral protein.
By way of further information, applicants found that this type of linkage reduces the ability of the [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide to bind to the GnRH receptor by 99%. In addition, the conjugation procedure reduces the toxicity of the pokeweed antiviral protein by 99.5 in a cell-free translation system. However, despite large reductions in activity of both the GnRH analog and the sterilization agent by this particular conjugation procedure, some activity of each was maintained. The activity of this conjugate was also tested in a pituitary cell culture system. In this system, pituitary cells were incubated with the sterilization agent conjugated to [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide for 16 hours. After incubation, the sterilization agents were removed from the incubation media by extensive washing and the cells were then cultured for an additional 24 hours. The increase in total LH, i.e., that present in the media plus that in the cells during the 24 hour period, represents the ability of the treated cells to synthesize LH. Using this system, it was established that these toxic conjugates can completely inhibit synthesis of LH by the cultured cells. Thus, by this method, it was established that the compounds of this patent disclosure can inhibit synthesis of LH and presumably other proteins made by gonadotrophs since this class of compounds has the ability to inhibit all protein synthesis once they gain entry into a cell.
Applicants also tested these compounds using an in vivo model. The test system initially chosen was the ovariectomized female rat. The parameter examined was GnRH induced secretion of LH. The results of such an experiment with rats are shown in FIG. 1 A. It indicates that a single injection of a toxic conjugate (i.e., GnRH-A-T) wherein the toxic moiety (T) pokeweed antiviral protein and the GnRH-A moiety was [D-Lys 6 1 , des-Gly 10 ]-GnRH-ethylamide. During week 1, this compound induced secretion of LH equivalent to that of GnRH-A alone. This indicated that the sterilization agent conjugate was binding to the GnRH receptor in vivo. During week 2, release of LH was reduced by 50% in the GnRH-A treated group (controls), but by >90% in the GnRH-A-T group. By the third week, the release of LH in the GnRH-A-T group had returned to the same level as that observed in the control animals. This indicated that a single treatment with the sterilization agent conjugate was probably not sufficient to completely kill the gonadotrophs in vivo. It might however be the basis for a temporary sterilization. Based upon this finding, a second experiment was conducted to examine the effect of 4 injections of a pokeweed antiviral sterilization conjugate at 3-day intervals on the ability of ovariectomized rats to release LH. In this experiment, the rats were unable to release LH in response to GnRH stimulation one month after initiation of the treatment (FIG. 1 B). These data strongly indicate the ability of these conjugates to permanently inhibit reproduction in intact male and female animals.
In another set of experiments, intact rats were given 4 injections of GnRH-A-T compounds, again wherein the toxic moiety T was selected from pokeweed antiviral protein, ricin A chain, and ribosome inhibiting proteins, of certain grains (again, those of wheat, corn, barley and rye,) at 3-day intervals and their subsequent reproductive capacity was compared to rats treated with only the respective toxin T or to that of untreated rats. In this experiment, treatment of male rats with only the toxin T did not reduce their fertility compared to controls (percentage of females that became pregnant was 100%). However, fertility was greatly reduced in those males that were treated with a GnRH-A-T agent such as, for example [D-Lys 6 -des-Gly 10 ]-GnRH-ethylamide conjugated to pokeweed antiviral protein, i.e., only 50% of the females exposed to males became pregnant. Moreover, fertility did not appear to increase with time after treatment. Histological examination of the testes of these rats indicated that most of the seminiferous tubules were devoid of sperm. However, 10% of the tubules appeared to still be producing sperm and probably accounted for the pregnancies observed. The weight of the testes was reduced by nearly 50% and did not recover within 6 months after the end of treatment. Thus, the effects of the treatment appeared to be permanent and dose related. Female rats treated with the toxic conjugate were sterile and remained so for at least 4 months (i.e., about 30 re-productive cycles) after the end of treatment. Most important is the fact that none of the rats treated with the toxic conjugate appeared to have any side effects.
Exemplary Chemical Experimental Methods
1. Synthesis of [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide. Synthesis of this analogue was accomplished using the solid phase method on hydroxymethyl resin and cleavage from the resin by ethyl amine, yielding the ethylamide. Following HF cleavage of protecting groups from side chains the peptide was purified by countercurrent distribution, purity of the peptide was assured by TLC, paper electrophoresis, and amino acid analysis of the acid hydrolysate.
2. Applicants also produced a caproic acid derivative (134.91 mg) and the lysosomal hydrolase sensitive tetrapeptide spacer Leu-Ala-Leu-Ala-D Lys 6 (16.25 mg).
3. Conjugation of [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide to toxins using SPDP. Applicants endeavored to construct toxic conjugates of [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide with the ricin A-chain. At the time these studies were initiated, Ricin A-chain was commercially available, but applicants found it to be both expensive and very unstable to temperature changes or conjugation procedures. Construction of an effective hemitoxin [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide conjugate requires coupling of hemitoxin to hormone via a protein cross-linking reagent that does not block either the enzymatic activity of the hemitoxin or the binding specificity of the hormone. Therefore, applicants investigated a number of different hemitoxins in addition to ricin A and pokeweed antiviral protein and a number of different conjugation techniques. This work was largely directed at purification of certain plant hemitoxins, i.e., ribosomal inhibitory proteins, (“RIP”), a relatively recently recognized group of proteins which share the ability to enzymically inactivate mammalian ribosomes. Such toxins are potentially promising as alternatives to the more familiar A-chains of, for example, ricin in that they do not require separation from the cell-binding B-chains. The bi-functional coupling reagent most commonly used for this purpose is N-succinimidyl 3-(2-pyridyldithio) propionate (SPDP). This compound forms covalent linkages to either free amino or sulfhydryl groups on proteins, but SPDP normally is attached to amino groups in hemitoxins, partly because many hemitoxins do not contain sylfhydryls that are available for coupling.
Initial experiments examined the reaction of SPDP with both the wheat and barley hemitoxins at various SPDP: hemitoxin ratios. The reactions were carried out at pH 9 for 30 minutes at 23° C. at a protein concentration of 0.6 mg/ml. After 30 minutes a 20-fold molar excess (over SPDP) of lysine was added to react with free SPDP and the hemitoxins diluted and assayed for inhibition of polyphenylalanine synthesis on Ehrlich ascites cell ribosomes. The results are presented in FIG. 2 .
FIG. 2 is intended to show inactivation of certain grain hemitoxins by SPDP conjugation. It indicates that even 1:1 ratios of SPDP to hemitoxin result in significant inactivation which is complete at a 20:1 ratio. A commonly used 2-3 fold ratio would result in >95% inactivation. Applicants' study was expanded to include hemitoxins from corn and pokeweed. Reactions were carried out in phosphate buffers at neutral and acidic pH's in anticipation that under acidic conditions differences in pKa of lysine amino groups or conformational changes in some of the proteins might protect enzymic activity. However, in all conditions and with all 4 hemitoxin proteins, significant inactivation occurred and as quantitative activity measurements of hemitoxins were rather imprecise; hence applicants were unable to conclude that residual activity was not from unreacted hemitoxin. Moreover, these particular experiments indicated SPDP would be unsuitable as a coupling reagent for preparing many GnRH-A-T conjugates.
4. Conjugation of [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide to toxins using Carbodiimide. Applicants examined the ability of the water soluble coupling reagent, carbodiimide linkages in this class of compounds. Although carbodiimide has been used successfully for coupling polypeptide hormones to proteins, applicants are unaware of any studies reporting its use in preparing toxin-protein conjugates. However, its use turned out to be attractive since it couples through carboxyl groups on the hemitoxin rather than amino groups. It should also be noted that applicants'synthetic GnRH analogs are blocked at the carboxyl and amino termini, thus leaving, for example, D-lys 6 amine as the only reactive moiety. Use of large molar ratios of GnRH favors reaction of the hemitoxin to the analog rather than to itself.
FIG. 3 shows the successful results of this approach. It represents a SDS-PAGE analysis of carbodiimide conjugated hemitoxins. In order to carry out these experiments, a 30:1 molar ratio of [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide to hemitoxin was reacted with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDAC) in water at 23° C. for 30 minutes and the reaction mixture passed through a Bio-GeI P6 column to desalt the product. Protein containing fractions were assayed for residual activity (see text) and the reaction products examined by SDS polyacrylamide gel electrophoresis. Lanes 1, and 6 are standards; lane 2, barley; lane 3, barley-GnRH; Lane 4, pokeweed; lane 5, pokeweed-GnRH; lane 7, rye-GnRH; lane 8, rye; lane 9, gelonin-GnRH; lane 10, gelonin. Conjugation in each case resulted in a 32 kDa product which was distinct from the 30 kDa hemitoxin alone, and which (by enzyme assay) retained 10% of the original activity. Hemitoxins from barley, rye, wheat and the unrelated pokeweed and gelonin hemitoxins have each been successfully conjugated in this fashion and all retain about 10% of original toxicity in ascites ribosomal assay. Biologic studies with these conjugates were then completed in the manner hereinafter described.
5. Conjugation of [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide to toxins using 2-iminothiolane. Although 2-iminothiolane, like SPDP, reacts with free amino groups on proteins, it does not affect the activity of gelonin or PAP. Applicants have hypothesized that perhaps the reason 2-iminothiolane differs from SPDP in this regard is that it reacts with a different amino group on the protein or that it places a positive charge on the active amino group and thereby preserves enzymatic activity. In any case, applicants reacted 2-iminothiolane with barley hemitoxin at several reagent: protein ratios, separated the protein from unreacted 2-iminothiolane by gel exclusion chromatography on Sephadex G-25 and quantitated the amount of sulfhydryl groups introduced onto the hemitoxin by sulfhydryl exchange with the reactive, chromogenic disulfide 5,5′-dithiobis (2-nitrobenzoic acid) (DTNB). The derivatized barley hemitoxin preparations were assayed for their ability to inhibit protein synthesis in ascites cell-free extracts and were found to have retained full activity.
FIG. 4 depicts inhibition of protein synthesis by 2-iminothiolane-conjugated barley hemitoxin. Barley hemitoxin was incubated at 0° C. for 90 minutes with 0 (o), 8-fold (x) or 24-fold (o) molar excess of 2-iminothiolane. The derivatized hemitoxins were then assayed for their ability to inhibit protein synthesis in ascites cell-free extracts. Proteins contained 0 (o), 0.76 (x) and 1.44 (o) moles of 2-iminothiolane bound per mole of hemitoxin.
Conjugation between the barley hemitoxin and [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide was carried out by disulfide exchange. A sulfhydryl group was introduced into [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide by reacting the hormone with a 16-fold molar excess of 2-iminothiolane at 0° C. for 2 hours. Derivatized [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide was separated from unreacted 2-iminothiolane by chromatography on a Bio-Gel P-2 column equilibrated with 30% acetic acid. Acetic acid was removed from the isolated hormone by rotary evaporation followed by lyophilization. A reactive disulfide was prepared from barley hemitoxin as described above by incubating the hemitoxin with a 24-fold molar excess of 2-iminothiolane, isolating the protein and reacting it with DTNB to prepare the disulfide, and separating the hemitoxin from unreacted DTNB by column chromatography on Sephadex G-25. A 12-fold molar excess of derivatized [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide was added to hemitoxin disulfide and disulfide exchange permitted to occur overnight at 4° C. Hemitoxin was separated from unconjugated GnRH by Sephadex G-25 column chromatography.
The reaction products were analyzed by SDS-polyacrylamide gel electrophoresis under non-reducing conditions. Analysis showed that the coupling reaction had converted approximately 50% of the 29 kDa barley hemitoxin (track 5) into a 31 kDa product (tracks 1-4) corresponding to a 1:1 hemitoxin- [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide conjugate. The faint band of unreacted [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide that can be seen in track 1 migrating ahead of the 14 kDa marker disappeared following acetone precipitation of the hemitoxin (track 2) or gel exclusion chromatography on Sephadex G-25 (tracks 3 & 4). The mixture of conjugate and unreacted hemitoxin was not purified further but was assayed directly for pituitary cell binding and killing.
FIG. 4A depicts SDS-PAGE analysis of barley hemitoxin after conjugation to [D-Lys6, des-Gly 10 ]-GnRH-ethylamide using 2-iminothiolane. Reaction products were analyzed before (tracks 1 & 2) and after tracks 3 & 4) Sephadex G-25 chromatography, and before (tracks 1 & 3) and after (tracks 2 & 4) concentrating by acetone precipitation. Track 5 contained unreacted hemitoxin.
6. Conjugate Binding Studies. In order to assess whether [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide toxin conjugates retain their ability to bind to receptors, the following assay was devised. Various concentrations of each conjugate were evaluated for their ability to displace 50,000 cpm 125 I-D Ala 6 -GnRH-ethylamide from bovine pituitary membranes. After incubation for 4 hours in standard conditions at 4° C., membranes were pelleted, counted in a gamma counter to determine the bound labelled ligand, and the ability of each conjugate to displace 50% of the label (IC 50 for unlabelled [D-Lys 6 1 , des-Gly 10 ]-GnRH-ethylamide. FIG. 5 indicates the results of binding curves obtained in these experiments. Also shown are the calculated number of molecules required to displace 1 molecule of unconjugated [D-Lys 6 , des-Gly 10 ]-GnRH-ethylamide. For example, FIG. 5 shows competitive binding of toxin conjugates to bovine pituitary membranes. The abbreviations are: 2IT, 2-iminothiolane; PAP, Pokeweed Antiviral Protein; SPDP, N-succinimidyl 3-(2-pyridyldithio) propionate; CI, Carbodiimide; EACA, Epsilon-amino caproic acid linker. Grain names refer to the purified hemitoxin source.
The data in FIG. 5 was critical in determining applicants' next steps. Several conclusions were reached. First, SPDP severely limits toxin activity (see FIG. 2 ). It also produces conjugates with greatly reduced binding activity (compare PAP-SPDP with Barley carbodiimide). On the other hand, use of carbodiimide produced conjugates with 3-40 fold improved binding compared to SPDP. However, there were differences among the hemitoxins used. For example, the wheat, rye and gelonin carbodiimide conjugates all showed greater binding than did the barley carbodiimide conjugate. However, the barley carbodiimide conjugate retained greater toxicity than the other grain hemitoxin conjugates in the cell free protein synthesis assay (data not shown). In this case, use of a spacer arm actually decreased binding affinity. Finally, the 2-iminothiolane conjugate made with barley hemitoxin as described above retained both 100% toxicity in the cell free system (see generally FIG. 4) and was as active as the best of the carbodiimide conjugates in binding. Applicants noted a 4.5 fold reduction in binding compared to the unconjugated [D-Lys 6 , desGly 10 ]-GnRH-ethylamide. This was quite acceptable since native GnRH has also only about {fraction (1/30)} the binding activity as this analogue (data not shown). Thus, after this exploratory work was completed, applicants carried out most further work with either the PAP-SPDP-[D-Lys 6 , desGly 10 ]-GnRH-ethylamide or the barley 2-imminothiolane [D-Lys 6 , desGly 10 ]-GnRH-ethylamide conjugate.
In Vitro Experiments
The effect of these compounds on ovine pituitary cells in suspension culture was measured. A pituitary was removed from a ewe, sliced thinly, and dissociated with a mix of collagenase, hyaluronidase, and DNAase. The cells were washed several times and resuspended in culture medium containing 30% ram's serum. Cells were cultured in a 37° shaking water bath in 50 ml flasks under 95% O 2 /5% CO 2 . In a typical experiment, cells were divided into four groups after dissociation and cultured overnight (20 hr) with 1) culture medium only, 2) 10 −8 M GnRH, 3) 3×10 −9 M Toxin-[D-Lys 6 , desGly 10 ]-GnRH-ethylamide (molarity expressed in terms of GnRH receptor binding activity) and 4) Toxin at the same concentration as Toxin-[D-Lys 6 , desGly 10 ]-GnRH-ethylamide. After pretreatment, the cells were washed 6 times, counted, and small aliquots removed for testing. The remainder were cultured in plain medium for 24 hours. To test the cells, aliquots of 500,000 cells were washed and resuspended in challenge medium containing 10 −7 M GnRH for 2 hours at 37° C. 3 ml of cold Gel-PBS was added to each tube, cells were centrifuged, and the media was measured for LH content. The four pretreatment groups were evaluated for their ability to synthesize and secrete LH immediately after treatment and after the 24 hour recovery period. The results of one experiment are shown in Table III.
TABLE III
LH Synthesis and Release by Ovine Pituitary Cells
(ng per 5 × 10 6 cells)
TREATMENT 1
SYNTHESIS 2
CONTROL
526.3
10 −8 M GnRH
545.5
PAP
137
PAP-D-Lys 6
0
1 Cells were incubated with the various treatments for 16 hours.
2 Synthesis of LH was measured during a 24 hour period of culture after the agents were removed from the cells.
These data, although obtained with the least promising of our conjugates, reveal a large and specific effect of PAP-SPDP-[D-Lys 6 , desGly 10 ]-GnRH-ethylamide (ethylamide is abbreviated as “EA” in Table III) on the gonadotropes ability to synthesize and secrete LH. It is not possible to determine whether the gonadotropes were specifically killed as they comprise <10% of the total number of pituitary cells, but the data strongly suggest the conjugate disrupted their normal function.
Applicants then tested the more promising Barley-2IT-[D-Lys 6 , desGly 10 ]-GnRH-ethylamide conjugate in similar assay systems. Table IV shows the results of a similar experiment. Ovine pituitary cells were again placed in culture with various agents and the total LH in the cells and media determined after a 24 hour exposure, wash, and further 24 hour culture in standard media.
TABLE IV
Total Culture LH after Exposure to GnRH
and Toxin Conjugates with or without Lysosomal Agents
Total LH
(Ng/10 5 cells in
Incubation Condition
Culture)
Control
1.90
D-Lys 6 GnRH-EA
1.62
Barley Toxin
1.49
Barley Toxin-2IT-D-Lys 6 GnRH-EA
.91
Barley Toxin-2IT-D-Lys 6 GnRH-EA + Monensin
1.83
Barley Toxin-2IT-D-Lys 6 GnRH-EA + Chloroquine
.62
Barley Toxin-2IT-D-Lys 6 GnRH-EA + NH 4 Cl
1.33
Barley Toxin-2IT-D-Lys 6 GnRH-EA +
1.13
Killed Adenovirus
These results indicate a specific killing effect of the toxin conjugate after only 24 hours of exposure. The lysosomally active agents do not potentiate this effect with the exception of chloroquine. When such experiments are combined with secondary challenge by GnRH, it appears that few gonadotropes are able to synthesize new LH after exposure to the barley toxin conjugate (data not shown).
7. In vivo Experiments. Several experiments were done to determine the effects of the pokeweed toxin (PAP)-SPDP-[D-Lys 6 , desGly 10 ]-GnRH-ethylamide conjugate in adult Sprague Dawley rats. Groups of 5-7 rats were treated with 20 ng of analogue; 20 ng conjugate (receptor binding assay equivalents), saline, or a conjugate made from a protein of similar molecular weight to the pokeweed toxin (carbonic anhydrase or ovalbumin). The most effective time course was found to be weekly injections for 4 weeks. The effect of such treatment was monitored in several ways. The ability of the animals to respond to a GnRH analogue challenge by measuring LH and/or serum testosterone levels 30-90 minutes after injection was followed. No difference was found among the groups. This result might be expected, since inducible LH release in intact animals is quite small secondary to chronic feedback suppression by the testicular androgens. Secondly, applicants followed gonad weights and found the testes in the PAP-[D-Lys 6 , desGly 10 ]-GnRH-ethylamide group to be decreased by 50%, although the control conjugates had similar effects. The PAP-[D-Lys 6 , desGly 10 ]-GnRH and carbonic anhydrase conjugate groups were found to be infertile in breeding tests, indicating a potential effect of this enzyme on testis tissue. Interestingly, light microscopy of these animals revealed no changes in the pituitaries, but interstitial (Leydig) cell depletion in the PAP-SPDP-[D-Lys 6 , desGly 10 ]-GnRH-ethylamide treated group, indicating a possible specific cellular effect on rat testicular function. This was not surprising since there are GnRH receptors on Leydig cells in the rat testis.
Applicants also tested the PAP-carbodiimide-[D-Lys 6 , desGly 10 ]-GnRH-ethylamide conjugate in ovariectomized female rats. In contrast to the SPDP conjugate, and in this system where gonadal feedback is not a problem, this drug appears capable of producing a 15 fold decrease in the serum LH response to GnRH analogue challenge (FIG. 1A or 1 B), again indicating the importance of applicant's studies on various linking techniques.
FIG. 1B indicates the results of a challenge by one of applicants' compounds to ovariectomized rats. Serum concentrations of LH in ovariectomized rats treated with saline (hatched bars) or pokeweed antiviral protein conjugated to a GnRH super-agonist (solid bars) are depicted. The open space above the bars indicates the amount of LH released in response to a GnRH challenge. The challenges were administered on the first day of treatment and again 4 weeks later. Compared to control there was greater than a 90% reduction in LH release after GnRH challenge at 4 weeks of treatment.
Based on the above data (with regards to LH synthesis inhibition) applicants then carried out experiments in intact male and female rats. Animals received 4 injections at 3 day intervals of PAP-CI-[D-Lys 6 , desGly 10 ]-GnRH-ethylamide or of the GnRH analogue or toxin alone or saline. Conjugate treated male animals (but not control) showed a 50% reduction in fertility (i.e., 50% of females exposed to these male animals became pregnant, compared to 100% of controls). Histologic examination of the testes of experimental animals revealed residual spermatogenesis in about 10% of tubules. In conjugate treated female animals, fertility was abrogated for more than 4 months (time sufficient for about 30 reproductive cycles in normal animals) following treatment. There were no side effects noted from these injections.
To further understand the effect of hemitoxins and conjugates on non-target tissues, applicants initiated studies on the tissue distribution of 125 I-toxin-conjugates and have demonstrated important differences among the toxins in (for example) concentration in the kidneys, indicating the importance of testing the various proteins to avoid potential non-target tissue toxicity. For example, applicants have found that the tissue/serum ratio of unconjugated PAP 2 hours after injection for various organs ranges from 0.03 in brain to 85.5 in kidney. In contrast, unconjugated barley hemitoxin is 8-fold less concentrated in kidney (see Table IV). Conjugation with the GnRH analogue alters these ratios considerably.
TABLE V
Tissue Distribution of Hemitoxins
and Hemitoxin Conjugates
Tissue
PAP
PAP-SPDP-D-Lys 6 GnRH
Pituitary
.20
.11
Brain
.03
.01
Adrenal
.48
.02
Kidney
85.5
12.6
Liver
2.48
1.07
Spleen
2.29
.73
Testis
.03
.02
Tissue/Serum Ratio of Labeled Protein
GnRH
Barley
Barley-CI-D-Lys 6 GnRH
Pituitary
1.08
1.06
Brain
.04
.04
Adrenal
.70
1.5
Kidney
10.5
4.0
Liver
.43
3.52
Spleen
.4
5.07
Testis
.10
.10
Thus these experiments produced a group of compounds capable of sterilizing (temporarily or permanently) animals by destroying the gonadotrophs of an animal's anterior pituitary gland. These compounds can be administered in the form of pharmaceutically acceptable, and otherwise nontoxic salts. It should also be noted that these compounds can be administered individually, or in combination with each other, to animals intravenously, subcutaneously, intramuscularly or orally to achieve fertility inhibition and/or control. Preferably administration will be intravenous or intramuscular in a suitable carrier such as, for example, in isotonic saline phosphate buffer solutions or the like. They also can be used in applications calling for reversible suppression of gonadal activity, such as for the management of precocious puberty or during radiation or chemotherapy. Effective dosages will vary with the form of administration and the particular species of mammal being treated. An example of one typical dosage form is a physiological saline solution containing the peptide which solution is administered to provide a dose in the range of about 0.1 to 10 mg/kg of body weight.
Conjugation of dK 6 -GnRH with PAP.
Fourteen moles of dK 6 -GnRH are dissolved in 1 ml of methanol (MeOH) and then mixed (on ice) with 9.61 N,N-diisopropylethylamine (DIPEA). The reaction is started by addition of 17 moles of 2-iminothiolane (2-IT) dissolved in 0.5 ml of MeOH. After 2 h incubation at room temperature the solution is acidified with 71 CH 3 COOH (100%) and dried with a stream of nitrogen. The progress of the reaction is monitored by HPLC and the product is also analyzed by MS. This reaction is faster in DMF and better yields can be achieved. MeOH is also a more convenient solvent.
Modification of PAP with N-[-maleinidobutyrloxy]sulfosuccinimide ester (Sulfo-GMBS). A 4.8 mole sample of PAP (144 mg) is dissolved in 4 ml of 0.05 M sodium phosphate, 0.1 M NaCl, 1 MEDIA, pH 7.4. The protein solution is mixed with 14.7 moles of Sulfo-GMBS dissolved in 4 ml of the same buffer. The reaction is allowed to proceed for 40-60 minutes at room temperature.
Reaction of SH-GnRH with modified PAP. Freshly prepared SH-GnRH is dissolved in deoxygenated 0.05 M sodium phosphate, 0.1 M NaCl, 1 mM EDTA, pH 7.4 and mixed with freshly prepared deoxygenated maleimibobutyryl-PAP solution. The final pH is 7.0-7.2. After incubation for 30-40 minutes at room temperature the reaction mixture is acidified to pH 4.5-5.0 with 1 M CH 3 COOH, spun and the supernatant applied to a BioGel P-60 or Superdex-75 column equilibrated in 0.1 M NaCl. The fraction containing GnRH-PAP conjugate is concentrated, desalted on Sephadex G-25 (in the presence of 0.05 M NH 4 HCO 3 ) and then lyophilized yielding 90 mg of protein. The pH 7.0-7.4 of the reaction of PAP with Sulfo-GMBS is chosen to increase reactivity of the -amino group with respect to -amino groups. Under the same conditions a higher, 70-80%, conjugation yield is obtained with ribonuclease A.
Although the invention has been described with regard to its preferred embodiments, it will be apparent to those skilled in this art, upon reading the above detailed description and examples, that various modifications and extensions can be made thereto without departing from the spirit of the present invention and that the scope of said invention shall be limited only by the scope of the appended claims.
2
10 amino acids
amino acid
single
linear
peptide
not provided
Region
/note= “Xaa = lysine, D-lysine,
ornithine, D-ornithine, glutamic acid, D-glutamic acid,
aspartic acid, D-aspartic acid, cysteine, D-cysteine,
tyrosine or D-tyrosine”
1
Glu His Trp Ser Tyr Xaa Leu Arg Pro Glx
1 5 10
10 amino acids
amino acid
single
linear
peptide
not provided
2
Glu His Trp Ser Tyr Asp Lys Leu Arg Pro
1 5 10
|
Certain toxic compounds (T) such as, for example, compounds based upon diphtheria toxin, ricin toxin, pseudomonas exotoxin, α-amanitin, pokeweed antiviral protein (PAP), ribosome inhibiting proteins, especially the ribosome inhibiting proteins of barley, wheat, corn, rye, gelonin and abrin, as well as certain cytotoxic chemicals such as, for example, melphalan and daunomycin can be conjugated to certain analogs of gonadotropin-releasing hormone to form a class of compounds which, when injected into an animal, destroy the gonadotrophs of the animal's anterior pituitary gland. Hence such compounds may be used to sterilize such animals and/or to treat certain sex hormone related diseases.
| 2
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the field of inspection equipment and more particularly to equipment for automatically detecting the presence of certain liquids and foreign objects in containers.
2. Prior Art
Electronic bottle inspectors for inspecting the interior of empty bottles for opaque foreign matter are well known in the prior art. Examples of such prior systems include those disclosed in U.S. Pat. Nos. 3,133,640 and 3,415,370. The latter patent is of particular interest as the present invention comprises a modification of a prior art system very similar to that disclosed in that patent. Such incorporation systems are generally characterized by a means of support of the bottle to be inspected from the side thereof with a light source, frequently an incandescent light source, below the bottle to direct light through the bottom thereof. Light passing through the bottom of the bottle and upward through the neck of the bottle is generally focused thereabove to provide an image of the bottom of the bottle, with some form of scanner or sensor array for sensing different portions of the image to determine relative light and dark areas, the dark areas, of course, representing the presence of opaque objects.
In the system of U.S. Pat. No. 3,415,370 the light passing through the bottom of the bottle and upward through the neck is focused by a lens thereabove onto the face of a rotating scanner, characterized by a concave surface having a non-reflective background with a single mirror segment thereon for sweeping the image focused onto the scanner. The axis of rotation of the scanner is inclined somewhat to the axis of the bottle so that the portion of the image reflected by the reflective portion of the scanner, being focused by the concave curvature thereon, is focused onto a detector displaced somewhat to the side of the focusing lens. The system of that patent also incorporates a neck inspection feature which could be utilized with the present invention, though in the preferred embodiment is not.
Equipment generally in accordance with U.S. Pat. No. 3,415,370, though not incorporating the neck inspection feature, has been manufactured for a number of years by Industrial Automation Corporation of Santa Barbara, California, assignor of the present invention. In that equipment a pair of approximately diametrically opposed mirror segments are utilized on the rotating scanner, and a bottle support mechanism generally in accordance with U.S. Pat. No. 3,975,260 is utilized.
The infra-red radiation absorption characteristics of water and water vapor are well known. (See for example, U.S. Pat. Nos. 2,703,844 and 3,021,427 and 3,089,382 and 3,153,722, and also Wood, the review of Scientific Instruments, Vol. 29, No. 1, pages 36-41, January 1958.) These absorption characteristics have been used to detect the presence or absence of a liquid at a particular level in a container, such as in U.S. Pat. No. 3,225,191, and to measure the relative amounts of water in containers such as in U.S. Pat. No. 2,321,900. The fact that infra-red energy may pass through containers which are relatively opaque to visible light is disclosed in the last stated patent, as well as U.S. Pat. No. 2,945,588. Other patents utilizing the absorption characteristics of water for detecting purposes includes U.S. Pat. No. 3,150,264 and No. 3,043,956, and for the detection of foreign matter in liquids using infra-red energy in U.S. Pat. No. 2,132,447.
Finally a system for inspection of empty beverage bottles is described starting on pages 52 and 53 of Food Processing, March, 1978. In accordance with that disclosure the bottom of a bottle is inspected from above for contaminants utilizing a dual inspection system comprised of superimposed radial and raster scanners. A beam splitter diverts a portion of the light gathered from the bottle bottom by the lens system and directs it to the raster scanner that gives uniform inspection over the center portion of the container. A coaxial radial scanner receives the remainder of the light and processes a portion of it to scan the outer portion of the container. The coaxial radial scanner system allows part of the light to pass on to the residual liquid detector that uses an infra-red scanner to detect the presence of minute amounts of water in the bottle. It is unknown at this time whether this system constitutes prior art, i.e. has priority of invention over the present invention.
BRIEF SUMMARY OF THE INVENTION
An electronic bottle inspector having particle and liquid detection capabilities through the use of sensing systems in the visible and infra-red light range. For particle inspection in the visible light range, light from a source, typically an incandescent source passing through the bottom of a bottle, is focused above the neck of the bottle to present an image of the bottom of the bottle on a rotating scanner characterized by a generally non-reflective background having one or more reflecting segments thereon. The scanner rotates at high speed so that the reflecting segment or segments scans the image focused thereon, with at least the reflective segments being contoured so that light falling thereon from the respective portion of the bottle bottom image is focused onto a detector. The particulate matter on the bottom of the bottle will block the light, creating a dip in detector output when that portion of the image is scanned. For liquid detection one or more holes are provided through the non-reflective portions of the scanner, with an infra-red detector being located therebehind to detect the infra-red radiation passing through the holes. Filtering of the light received by the detector allows peaking of the sensitivity of the system around one of the absorption bands of the liquid, with a drop in AC coupled amplitude of the infra-red detector providing an indication of the presence of the liquid.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an electronic bottle inspector incorporating the present invention.
FIG. 2 is a view taken along line 2--2 of FIG. 1.
FIG. 3 is a view taken along line 3--3 of FIG. 2.
FIG. 4 is a view taken along line 4--4 of FIG. 3.
FIG. 5 is a view taken along line 5--5 of FIG. 4.
FIG. 6 is a side view of the scanner taken on an expanded scale to illustrate the location of the infra-red detector relative to the scanner.
FIG. 7 is a block diagram of the electronics for providing reject signals upon the occurrence of a localized opaque obstruction in a bottle bottom, a distributed obstruction in the bottle bottom and/or a water-based solution.
DETAILED DESCRIPTION OF THE INVENTION
First referring to FIG. 1, a perspective view of an electronic bottle inspector which may incorporate the present invention may be seen. The bottle inspector is characterized by a base 20 supported on legs 22 and in turn supporting an inspection head thereabove. As may be seen in greater detail in FIGS. 2 and 3 also, a supply conveyor 24 supplies bottles to the inspection machine, which bottles are picked up by rotating starwheel assembly comprising an upper starwheel 26 and a lower starwheel 28 supported on a central shaft 30 supported by the base 20. The individual bottles are gripped by the neck thereof by clamps 32 (see FIG. 3) to support the bottles from the side, the bottles being further confined by guides 34 and 36. Also a pair of idler starwheels 38 are provided adjacent the transition between the supply conveyor 24 and the starwheels 26 and 28 to further guide the bottles in that region. The bottles pass under the inspection station or position 40 at which time they are inspected by the inspection head 24, proceeding to the delivery guides 42 to be redeposited on the conveyor 24 if they pass inspection, or to be sooner delivered to rejected bottle storage coral 44 if the bottles do not pass inspection. These aspects of the system incorporating the present invention are generally in accordance with the disclosure of U.S. Pat. No. 3,975,260 assigned to the assignee of the present invention.
Now referring more specifically to FIGS. 3, 4 and 5, various details of the inspection system for inspecting bottles using visible light to detect opaque foreign matter therein may be seen. FIG. 3 is a view taken in partial cross-section through the inspection position 40 and the axis of rotation of the main starwheels, as shown by the section line 3--3 in FIG. 2. FIG. 4, on the otherhand, is a view also taken through the inspection position, though perpendicular to the section of FIG. 3, as illustrated by the section lines 4--4 of FIG. 3. FIG. 5 is a view looking directly into the face of the scanner taken along line 5--5 of FIG. 4. An incandescent light source 46 is disposed immediately below the inspection position 40, projecting relatively diffuse light toward the bottom of the bottle 48 at the inspection position. The light passing through the bottom of the bottle and out through the neck thereof is focused by a lens 50 onto the face of a rotating scanner head 52 supported on shaft 54 of motor 56 and rotated at high speed. The motor 56 (perhaps more accurately the motor mounting bracket as the motor itself, of conventional design, is housed therein and retained in position by clamp screw 58,) is fastened to the back wall 60 of the inspection head 24 by screws 62. The scanner head 52 is provided with a pair of reflecting approximately radially disposed sections 64 on an otherwise generally non-reflecting background 66. Thus, only the portion of the image of the bottom of the bottle which falls on the reflective segments 64 will be reflected by the scanner, the segments effectively sweeping or scanning the image at high speed because of the rotation of the scanner. The scanner surface or at least a portion of the surface containing the reflective elements 64 is generally spherical so as to focus the light reflected by the reflective element down to a detector 68 which provides an electrical signal on lines 70 which at any instant is proportional to the intensity of the light in the relatively small portions of the bottle image being reflected by the reflective segments 64 on the scanner. This signal, relatively uniform for a clean bottle, is continuously monitored by appropriate electronics to detect rates of changes of the signal indicative of a region of the image of low light intensity caused by an opaque object in the corresponding area of the bottle. The optical inspection system just described is similar to that described in U.S. Pat. No. 3,145,370 and has been utilized in electronic bottle inspectors manufactured by Industrial Automation Corporation of Santa Barbara, Calif. for many years.
The modification of the foregoing equipment to incorporate the present invention will now be described. It will subsequently be seen that the modification is particularly simple and interfaces extremely well with the scanner system just described. In particular, in the preferred embodiment, four equally spaced holes 72 are provided through the face of the scanner (see FIGS. 5 and 6) and an infra-red radiation sensor 74 is mounted therebehind. In the preferred embodiment the holes 72 are each positioned at a fixed radius on the scanner representing approximately 70% of the radial extent of the reflective portions. Furthermore the detector 74 is preferably located at a position generally radially inward with respect to the axis of the shaft 30 defining the axis of the rotary transport system moving the bottles in a circular arc past the inspection station. With such a detector location the infra-red energy passing through the openings in the scanner 52 and falling on the detector 74 is infra-red energy passing through a region of the bottom of the bottle being inspected approximately radially outward from the axis of the rotary transport system, i.e., in approximately region 76 shown in FIG. 3. In operation the centrifugal force on the wash water, caustic solution or any other liquid in the bottle will force that liquid outward to approximately position 76 shown in FIG. 3 so that the infra-red detector 74 is in effect viewing the portion of the bottle bottom most likely to be covered with the fluid. In that regard, it will be noted that the axis of the scanner, i.e. the axis of the motor shaft 54 about which the scanner rotates at high speed, is inclined with respect to the bottle being inspected as shown in FIG. 4 so that the reflected segment 64 reflects the portions of the visual image to the detector 68 located somewhat to the side of the axis of lens 50 and the bottle 48 being inspected. While this inclination obviously could be in any desired direction depending on the location of detector 68, in the preferred embodiment the inclination is achieved by the slight rotation of the motor housing about a radial axis of the rotary transport system. Accordingly, in this embodiment the projection of the scanner shaft 54 axis in the view of FIG. 6 is aligned with the lens and the bottle being inspected.
It was previously mentioned that the scanner 52 is located substantially at the focal plane of the image of the bottom of a bottle so that the reflective segments of the scanner scan the image on rotation thereof. Assuming the infra-red image has substantially the same focal point (though not a specific requirement) the portion of the infra-red image received by the detector 74 will in general not be well focused. However, this is of little consequence as the only sweeping of the infra-red image occurs not as a result of the rotating scanner but instead merely as a result of the motion of the bottle past the inspection position. Accordingly the detector 74 is in general responding to the level of the infra-red radiation incident thereto which will come generally from region 76 of FIG. 3, as opposed to responding to sharply focused portions of the infra-red image.
Now referring to FIG. 7, a block diagram of the electronics used for signal processing in the preferred embodiment may be seen. In the previous description, specifically with respect to FIG. 2, an inspection position 40 immediately under the inspection head was identified. In reality, however, a moving bottle is inspected by the stationary inspection head so that the bottle and the starwheel supporting the bottle actually move through a small arc during the relatively short inspection period. In the preferred embodiment the scanner rotates at approximately 12,000 rpm so that the bottle bottom may be quickly scanned before false signals might be derived from the edges of the bottle. Thus, as a bottle approaches position 40 (FIG. 2), a mechanical reference on the starwheel assembly trips the light beam from the light emitting diode D1 in the resistor R1 and photodiode D1 combination. This is detected by photo transistor T1, the combination of the photo transistor and resistor R2 providing a signal to a trigger amplifier A1 to fire one shot pulse generator P1 (a monostable device) to provide a pulse on line 100 representing the initiation and duration of the inspection period for any particular bottle. In the preferred embodiment the one shot P1 provides a pulse width of approximately 6 milliseconds, representing approximately 1.2 revolutions of the scanner during the alotted inspection time window. This signal is used by the reject detection logic 102 to effectively enable any of three specific reject signals (to be subsequently described in detail) to actuate the reject solenoid 104, corresponding to the solenoid 62 of U.S. Pat. No. 3,975,260. (In FIG. 7 and in the descriptions to follow with respect thereto, the key aspects of the signal processing are shown and described for exemplary purposes, though other aspects of the signal processing well known in the art, such as voltage level shifting to allow conventional logic levels for the reject detection logic 102, signal inversion to allow use of conventional logic, etc. are not shown, but are presumed to be well known and included in the reject detection logic 102.)
The infra-red detector 74 (see also FIGS. 3 and 4) is a photoconductor coupled in series with resistor R3 between ±15 V D/C power supplies. The signal therefrom on line 106 is A/C coupled by capacitor C1 to amplifier A2. The output of amplifier A2 is successively filtered by a filter F1, amplified by amplifier A3, filtered by filter F2 and applied to one input of amplifier A4 operated as a comparator, the various amplifiers and filters being coupled by capacitors C2, C3 and C4. In the preferred embodiment the filters F1 are active filters having an 800 Hz bandpass, so that the signal out of filter F2 applied to one input of comparator A4 is predominantly an 800 Hz signal, the amplitude of which is dependent upon the infra-red radiation received by the detector 74. In that regard, since the scanner rotates at 200 cycles per second and four openings 72 are provided therein chopping the radiation four times per revolution, the 800 Hz signal of the filter F2 corresponds to the chopping frequency of the scanner, that is, the frequency at which the scanner chops the infra-red radiation falling on the detector 74.
The second input to the amplifier A4 is a reference voltage provided by resistors R4 and R5 coupled between a positive reference voltage and ground. During the inspection of a bottle having no water therein, the amplitude of the 800 Hz signal on line 106 caused by the repetitive illumination and blocking of illumination from the detector 74 will be substantial, resulting in an output of filter F2 having a peak-to-base amplitude exceeding the reference voltage applied to the other (positive) input of the amplifier A4. This will cause the output of the amplifier A4 to pulse negatively at the rate of 800 Hz, each pulse having a pulse width determined by the period for which the output of filter F2 exceeds the positive input of the amplifier A4. The pulse train output of the amplifier A4 is coupled through resistor R6 to a missing pulse detector 108, the combination of resistor R6 and diode D2 limiting the negative swing of the input to detector 108.
In the preferred embodiment the missing pulse detector is comprised of an integrated circuit generally referred to as a 555 timer connected as shown under the heading "Missing Pulse Detector" on page 6-81 of the publication entitled Signetics Linear Integrated Circuits, put out by Signetics of Sunnyvale, Calif. The time delay, as described therein, is chosen to somewhat exceed the period of an 800 Hz signal so that the output of the missing pulse detector will remain in one state so long as an 800 Hz signal is received from amplifier A4, but will change to the opposite state shortly after one, or no more than a few pulses are missing on the input to the detector. In that regard, since the total inspection period corresponds to approximately 1.2 rotations of the scanner, and the infra-red radiation on detector 74 is mechanically chopped four times per scanner rotation, approximately five pulses in the pulse train will be missing during the inspection period for a bottle containing water, caustic solution, etc., though it is preferable to trigger the output on some lesser number of missing pulses. Specifically, when there is a significant amount of water in the bottle being inspected, the amount of infra-red radiation received by detector 74 will be substantially reduced so that the amplitude of the A/C signal on line 106 will also be significantly reduced, resulting in a reduction of the peak-to-base amplitude of the output of filter F2 to a value less than the reference voltage applied to positive input of amplifier A4 and interrupting the pulse input to the missing pulse detector 108 to result in a reject signal to the reject detection logic 102.
In order to provide an adjustment in the sensitivity of the liquid detection portion of the circuitry, the gain of amplifier A2 is made adjustable by a manually adjustable potentiometer P1 in conjunction with resistors R7 and R8 in the feedback circuit of the amplifier. This allows adjustment of the sensitivity to allow the adjustment of the amount of liquid in the container which will be passed by the circuitry. In that regard, the liquid detection is potentially extremely sensitive because of the well known strong absorption characteristics of water when subjected to infra-red radiation of a wavelength for approximately 1.9 microns, and accordingly unless most minimal amounts of moisture in the container are to result in rejection, it has been found desirable to not use too sharp a bandpass filter for the interference filter over the detector to somewhat broaden the wavelength range of the radiation received thereby for sensitivity reduction purposes.
In the preferred embodiment, the particle inspection portion operating on the visible light is comprised of the photovoltaic sensor 68 which provides a signal to amplifier A5. The output of this amplifier is used for two purposes. In particular, foreign matter in the bottom of a bottle may have either of two characteristics, specifically (i), localized foreign matter such as specific objects, drops of paint, etc. and (ii), uniformly distributed foreign matter such as a coating of paint across the entire bottom of the bottle, a uniform layer of other foreign matter, etc. With respect to the inspection for the individual or localized contamination, the output of amplifier A5 is applied to an automatic gain control circuit GC1 which effectively normalizes the average signal, irrespective of variations thereof from bottle to bottle because of bottom thickness, bottle coloring, etc. The output of the automatic gain control circuit is serially coupled to a filter F3, amplifier A6, filter F4, amplifier A7, filter F5, amplifier A8, filter F6 and finally a last amplifier A9. The filters F3 through F6 in the preferred embodiment are passive high pass filters comprised of a series capacitor and resistor to ground, having a time constant of approximately 1 millisecond. Thus, slowly changing signals picked up by detector 68 are grossly attenuated by the filters, though any rapidly changing signal, even though the total amplitude of the change is not large, is essentially directly coupled through the filters to be amplified by the amplifiers to provide a substantial signal to amplifier A9. In that regard, amplifier A9 effectively operates as a comparator with the second input thereto being coupled to a reference voltage determined by resistor R9 and potentiometer P2. For the polarity shown for amplifier A9, so long as the output of filter F6 remains below the reference voltage determined by potentiometer P2 the output of amplifier A9 will remain positive, though when the output of filter F6 exceeds the positive reference voltage on the other input of amplifier A9 the output of the amplifier will change state, thereby signaling a reject signal to the reject detection logic 102. Since the reject signal out of amplifier A9 is dependent upon both the amplitude and the polarity of the signal out of filter F6 for this embodiment, rejection will occur based on a detector signal representing a transition from light to dark (or more accurately, from light to slightly less light representing a partial blockage of the light due to a small item on the bottle bottom), or on the transition from dark to light, but not both in the same system. In the preferred embodiment, polarities of the amplifiers, etc. are set so that rejection occurs on a transition from light to dark. In either case, however, it is to be noted that for this embodiment the rejection signal occurs on a single transition, which of course may represent either of the reflective segments 64 (see FIG. 5) sweeping the portion of the image being blocked by the item in the bottle, so that the inspection period representing approximately 1.2 rotations of the scanner is adequate for the full visual inspection of the bottle bottom.
With respect to the inspection for uniformly dispersed foreign matter on the bottle bottom, the output of amplifier A5 is directly amplified by amplifier A10 and coupled to amplifier A11, also connected as a comparator, the second input of the amplifier being coupled to a a potentiometer P3 for adjustment of the reject level. The potentiometer P3 allows the adjustment to compensate for variations in the light source, bottle thickness, etc., and more importantly for bottle coloring and/or partial opaqueness to visible light.
There has been described herein a new and unique modification of a prior art scanner which provides for the simultaneous inspection of bottles for opaque foreign matter, unilizing visible light, and for aquaeous-base solutions utilizing infra-red light. The system is particularly simple and highly reliable, providing the liquid detection capability at a minimum of increased cost. Obviously while four openings are provided in the scanner so as to chop the infra-red energy falling on the infra-red detector 800 times per second, such a selection was made based upon the manufacturer's recommendations regarding the operating frequency of the detector, and any lessor or greater number of openings may also be used. Similarly, while amplitude detection is used for the liquid detection and rate of change of signal is used for opaque particle detection, other signal conditioning techniques may also be used. Thus, while the present invention has been disclosed and described with respect to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.
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An electronic bottle inspector having particle and liquid detection capabilities through the use of sensing systems in the visible and infra-red light range. For particle inspection in the visible light range, light from a source, typically an incandescent source passing through the bottom of a bottle, is focused above the neck of the bottle to preset an image of the bottom of the bottle on a rotating scanner characterized by a generally non-reflective background having one or more reflecting segments thereon. The scanner rotates at high speed so that the reflecting segment or segments scans the image focused thereon, with at least the reflective segments being contoured so the light falling thereon from the respective portion of the bottle bottom image is focused onto a detector. The particulate matter on the bottom of the bottle will block the light, creating a dip in detector output when that portion of the image is scanned. For liquid detection one or more holes are provided through the non-reflective portions of the scanner, with an infra-red detector being located therebehind to detect the infra-red radiation passing through the holes. Filtering of the light received by the detector allows peaking of the sensitivity of the system around one of the absorption bands of the liquid, with a drop in AC coupled amplitude of the infra-red detector providing an indication of the presence of the liquid.
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LATIN NAME OF THE GENUS AND SPECIES OF THE PLANT CLAIMED
Impatiens walleriana
VARIETY DENOMINATION
‘Balfiepuna’
BACKGROUND OF THE INVENTION
The present invention comprises a new and distinct Double Impatiens plant, botanically known as Impatiens walleriana , and hereinafter referred to by the cultivar name ‘Balfiepuna’.
The new cultivar was developed by the inventor through a controlled breeding program in Elburn, Ill. The objective of the breeding program was the creation of impatiens cultivars which exhibit large, fully double flowers, are free-flowering and have a vigorous self-branching habit.
The female (seed) parent of ‘Balfiepuna’ was the proprietary Impatiens walleriana cultivar designated 573-1-3-1 (not patented) which exhibits a medium to vigorous habit and single, slightly cupped coral-rose flowers. The male (pollen) parent of ‘Balfiepuna’ was the proprietary Impatiens walleriana cultivar designated 3020-3-1-1 (not patented) which exhibits a vigorous loose habit, and large semi-double violet flowers.
Asexual reproduction of the new cultivar by two or three vegetative node stem cuttings has demonstrated that the characteristics of the new cultivar as herein described are firmly fixed and are retained through successive generations of such asexual propagation. Asexual propagation was carried out in West Chicago, Ill.
SUMMARY OF THE INVENTION
It was found that the cultivar of the present invention:
(a) exhibits attractive double purple flowers,
(b) forms dark green foliage,
(c) exhibits a good basal branching character and
(d) exhibits a upright mounded growth habit.
The new cultivar of the present invention can be compared to Rosebud ‘Purple Magic’ (U.S. Plant Pat. No. 8,359). In side by side comparisons it is found that the new cultivar is slightly more compact, has longer peduncles, longer leaves and darker flower color as detailed in Table 1, below.
TABLE 1
ROSEBUD ‘PURPLE
CHARACTERISTIC
‘BALFIEPUNA’
MAGIC’
LEAF LENGTH × WIDTH
5.1 cm × 3.1 cm
4.4 cm × 3 cm
PEDUNCLE LENGTH
1.7 cm
1.3 cm
FLOWER COLOR-
Closest to N78A
74A
UPPER SURFACE
BRIEF DESCRIPTION OF THE PHOTOGRAPH
The accompanying photographs show as nearly true as it is reasonably possible to make the same in color illustrations of this type, typical flower and foliage characteristics of the new cultivar. Sheet 1 shows a close-up view of a typical flower and foliage of ‘Baliepuna’. Sheet 2 shows a side perspective view of typical flowering plant of ‘Balfiepuna’. The plants were grown in a greenhouse at West Chicago, Ill., U.S.A.
DETAILED DESCRIPTION
The new cultivar has not been observed under all possible environmental conditions to date. Accordingly, it is possible that the phenotype may vary somewhat with variations in the environment, such as temperature, light intensity, and day length.
The chart used in the identification of colors described herein is the R.H.S. Colour Chart of The Royal Horticultural Society, London, England. The color values were determined on Aug. 30, 2000 between 3:00 and 3:45 p.m. under natural daylight conditions. The plants were produced from cuttings taken from stock plants and grown in a double polycarbonate covered greenhouse under conditions comparable to those used in commercial practice while utilizing a soilless growth medium and maintaining temperatures of approximately 72° F. during the day and approximately 65° F. during the night. The plants used for data collection and measurements were grown for 8 weeks.
Classification:
Botanical.—Impatiens walleriana cultivar ‘Balfiepuna’.
Commercial.— Double Impatiens.
Parentage: Proprietary seedling 573-1-3-1 (seed)×proprietary seedling 3020-3-1-1 (pollen).
Propagation:
Type cutting.— Two or three vegetative node stem cutting from near the center of plant
Time to initiate roots.— Approximately 7-14 days with the shorter times generally being experienced in the summer and the longer times in the winter.
Time to form roots.— Approximately 21 days.
Root description.— Fibrous, branching.
Plant description:
Form.— Upright and mounded.
Habit of growth.— Compact with good basal branching. A mature plant, at 8 weeks after planting of rooted cutting, commonly measures approximately 16.9 cm in height and approximately 31 cm in width.
Branching habit.— Basal branching.
Foliage.— Shape: Ovate with acute apex, attenuate base and serrate, ciliate margin. Venation pattern: Pinnate. Texture: Upper and lower surfaces are smooth. Size: Fully expanded leaves are approximately 5.1 cm in length and approximately 3.1 cm in width. Color of fully expanded leaves: Upper surface slightly darker than 137A, lower surface 138B with blotches of 184A. Petiole length is 1.4 cm.
Stem.— Color: 147C with overlay of 184A. Internode length is approximately 2.3 cm.
Flower description:
Flowering habit.— Freely flowering.
Natural flowering season.— Year round in greenhouse environment and spring until fall in the garden.
Flowers borne.— Above foliage arising from leaf axils.
Quantity of flowers.— Approximately 2 flowers and 2 buds per stem.
Flower diameter.— Approximately 3.5 cm.
Petals.— Shape: Obovate. Apex: emarginate. Base: Attenuate. Margin: Entire. Aspect: slightly cupped. Size: Length is 2.1 cm and width is 1.8 cm. Number: 21 per flower.
Flower color.— Fully opened flowers: Upper surface closest to N78A, lower surface N78A at edge and N78C in center. Very tiny area of 155D at attachment point.
Sepals.— Number: 4. Shape: Upper sepal is fused to underside of upper petal, lower sepal is modified to form nectary spur, lateral sepals are triangular, with smooth surfaces, entire margin, acute apex and truncate base. Color of lateral sepals: N144C.
Spur.— Size: Approximately 3 cm in length, 154D with overlay of 184A and tip of 59A.
Bud.— Shape: Ovate. Color: 72B. Length: 1.4 cm. Diameter: 1 cm.
Peduncle.— Length: Approximately 1.7 cm. Strength: Strong. Color: 146C.
Reproductive organs.— There tend to be no remaining reproductive organs. Occasional naked ovaries and occasional sterile, faciated stamen-like structures.
Seed production: Seed production has not been observed.
Disease resistance: Resistance to common diseases of Impatiens has not been observed.
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A new and distinct cultivar of Double Impatiens plant named ‘Balfiepuna’, characterized by its fully double purple flowers, upright and mounded habit, excellent basal branching and dark green leaves.
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CLAIM FOR PRIORITY
This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from an application for A Display Monitor Power Supply Apparatus With A Power Factor Correction Circuit earlier filed in the Korean Industrial Property Office on Mar. 29, 1996, and there duly assigned Ser. No. 96-9317.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to a power supply apparatus for display monitors, and more particularly, relates to a power supply apparatus having a simplified power factor correction circuit incorporated therein for display monitors in computer systems.
2. Related Art
Generally, power supplies for display monitors such as cathode ray tube (CRT) monitors commonly used with computer systems are designed to provide the necessary voltages and currents within the desired specifications using internal control. A typical computer-controlled power supply for use in computer systems includes an AC line rectification, AC loop regulation and power factor correction as disclosed in U.S. Pat. No. 5,019,717 for Computer-Controlled Uninterruptable Power Supply issued to McCurry et al. Some power supply systems may include power saving circuitry to reduce power consumption such as disclosed in U.S. Pat. No. 5,335,168 for Computer System With Power-Down Mode For Monitor issued to Walker, U.S. Pat. No. 5,375,245 for Apparatus For Automatically Reducing The Power Consumption Of A CRT Computer Monitor issued to Solhjell et al., and U.S. Pat. No. 5,481,730 for Monitoring And Control Of Power Supply Functions Using A Microcontroller issued to Brown et al. Other designs may include special circuitry to eliminate interferences such as disclosed in U.S. Pat. No. 4,886,979 for Power Source Circuit Device For Monitors And Host Computers issued to Chang, and hazard prevention circuitry to prevent hardware power failure such as disclosed in U.S. Pat. No. 5,481,732 for CRT Monitor Power Control Circuit issued to Shahbazi.
Typically, the power supply system is provided with a power-off circuit for interrupting the electrical power supply to the monitor during a power off. In many systems however, power regulation need to be improved because the output power voltage fluctuates as a function of input voltage as well as a load variation. Moreover, additional display power management signaling control circuit is necessarily required to support the power factor correction. Accordingly, further improvement in the power supply circuit design can be contemplated.
SUMMARY OF THE INVENTION
Accordingly, it is therefore an object of the present invention to provide a display monitor power supply apparatus which has a simplified circuit construction.
It is also an object to provide a display monitor power supply apparatus with a power factor correction circuit.
These and other objects of the present invention can be achieved by a display monitor power supply apparatus for power supply to a display monitor which includes a power factor correction circuit coupled to receive a primary voltage, for correcting a power factor of said primary voltage and generating a secondary voltage; a switch operable in response to a pulse signal; a switch control circuit for generating said pulse signal; a transformer including a primary winding and secondary windings connected to each other by mutual induction, in which the primary winding has a first terminal coupled to receive the secondary voltage and a second terminal connected to the switch, and in which the transformer is being supplied with primary induced voltage when the pulse signal has a primary duty ratio and supplied with secondary induced voltage lower than the primary induced voltage when the pulse signal has a secondary duty ratio; a rectifier for rectifying the primary and secondary induced voltages; and a smoothing circuit for smoothing an output voltage of the rectifier for application to the power factor correction circuit.
The present invention is more specifically described in the following paragraphs by reference to the drawings attached only by way of example.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the present invention, and many of the attendant advantages thereof, will become readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein:
FIG. 1 is a block diagram of an exemplary power supply apparatus for a display monitor;
FIG. 2 is a detailed circuit diagram of the exemplary power supply apparatus as shown in FIG. 1; and
FIG. 3 is a circuit diagram of a display monitor power supply apparatus having a power factor correction circuit constructed according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and particularly to FIG. 1, which illustrates an exemplary power supply apparatus for a display monitor. This power supply apparatus includes a fullwave rectifier 100, a power factor correction (PFC) circuit 200, a pulse width modulation (PWM) control circuit 300, a transformer 400, an output circuit 500, a feedback control circuit 600 and a display power management signaling (DPMS) control circuit 700 for supporting operation the PFC circuit 200. Rectifier 100 is coupled to an AC input voltage to rectify the AC input voltage and generate a DC output voltage. PFC circuit 200 then performs power factor correction in response to an output of the DPMS control circuit 700. PWM control circuit 300 performs pulse width modulation of an output of the PFC circuit 200. Transformer 400 includes primary windings connected to receive an output of the PWM control circuit 300 and secondary windings connected to output circuit 500 which rectifies voltage signals induced by the respective windings and generates regulated voltages. The feedback control circuit 600 controls the feedback of the PWM control circuit 300, and the DPMS control circuit 700 controls DPMS functions in response to control signals from a personal computer PC.
FIG. 2 is a detailed circuit diagram of the exemplary power supply apparatus as shown in FIG. 1. The fullwave rectifier 100 includes a bridge diode circuit which receives an AC input voltage of about 90˜260 Volts!. The PFC circuit 200 includes a PFC controller 210, a switching transistor TR1, a PFC power supply 220 for providing a source voltage to the PFC controller 210, a booster transformer T1 for allowing the output voltage of the fullwave rectifier 100 to be boosted or increased to about 400 Volts! according to the turning on/off of the switching transistor TR1, a rectifier 230 for rectifying the induced voltage, and a voltage divider 240 for regulating an output voltage changed according to the variation of the input voltage as well as load resistance. The power supply 220 includes a resistance R1, a diode D1 for rectifying a voltage induced by the secondary winding L2 of the booster transformer T1, and a capacitor C1 for smoothing the rectified voltage.
Both ends of the primary winding L P of the transformer 400 are connected to the PFC circuit 200 and the switching transistor TR2, respectively, and the secondary winding has three winding parts Ls1˜Ls3 which are connected to the rectifiers within the output circuit 500. The winding Ls1 at the secondary side of the transformer 400 has the number of turns enough to provide a first induced voltage which is four times as high as the source voltage applied to a microcomputer 710. The winding Ls2 has the number of turns enough to provide a second induced voltage which is four times as high as the other source voltage applied to a PWM controller 310.
The display power management signaling power supply modes registered by the video electronics standard association (VESA) can be, as well-known in this art, classified into a normal mode, a standby mode, a suspend mode and a power-off mode. According to this DPMS system, power consumption of a 17 inch display monitor is about 90 Watts! during normal mode, and about 8 Watts! during power-off mode.
The DPMS control circuit 700 functions as a circuit for controlling all the DPMS power supply modes in response to information from a personal computer, and includes a microcomputer 710, a photocoupler 720, transistors TR3-TR5, a diode D6 and resistances R8 and R9. The microcomputer 710 generates a control signal CS of low level under control of the personal computer PC during the normal mode and generates a control signal of high level during the power-off mode. During the normal mode, the PFC circuit 200 operates with a direct voltage from the fullwave rectifier circuit 100 and generates a DC voltage of about 400 V!. And then, by this DC voltage, a main power supply circuitry can be normally operated which comprises the PWM control circuit 300, the transformer 400, the output circuit 500 and the feedback control circuit 600. At this mode, the induced voltages from the winding parts Ls1˜Ls3 at the secondary winding of the transformer 400 are applied to the components of the display monitor.
During the power-off mode, however, when the information regarding the start point of the power-off mode is provided from the personal computer PC, the microcomputer 710 in the display monitor outputs a control signal CS of high level so that transistors TR3 and TR4 are simultaneously turned on. Then, the feedback current flowing to the feedback terminal F/B of the PWM controller 310 during the power-off mode is increased in amount more than that during the normal mode, and thereby the duty ratio of the output pulse generated from the PWM controller 310 is greatly decreased as compared with that during the normal mode. As a result, each voltage which is induced from the secondary winding of the transformer 400 is greatly reduced to, for example, about one quarter of the voltage induced during the normal mode. The induced voltages from the outputs V5 and V6 of the regulators 510 and 520 are maintained at the voltages of 5V and 12V, respectively. Also when the transistor TR4 is turned on, a current flows through a photodiode PD2 so that a phototransistor PT2 can be turned on. The transistor TR5 is then turned on, so that a supply voltage to the PFC controller 210 is intercepted. As a result, the PFC circuit 200 does not operate during the power-off mode.
As described above, in addition to the a power supply section 220 of the PFC controller 210, the exemplary power supply apparatus is provided with the power-off circuit, which is constituted by the photocoupler 720, the transistors TR4 and TR5, the diode D6 and the resistor R9 as shown in FIG. 2. This power-off circuit is provided to prevent a supply voltage from being supplied to the PFC controller 210 during the power-off mode, which results in increase of the production cost. In addition, the PFC controller 210 permits the output voltage V1 of the PFC circuit 200 to be regulated by means of a voltage divider circuit 240, which results in poor regulation of the supply voltage B+ that is generated from the power supply circuit 220 and provided for PFC controller 210. This is because the supply voltage B+ is changed according to the fluctuation of the input voltage of the controller 210 as well as load variation.
Turning now to FIG. 3, which illustrates a novel display monitor power supply apparatus constructed according to the principles of the present invention. The novel display monitor power supply apparatus includes a power factor correction (PFC) controller 210 whose source voltage is supplied directly to the primary winding of a transformer 400. The secondary windings include four winding parts Ls1˜Ls4 which are connected to the rectifiers.
As shown in FIG. 3, during a power-off mode of the power supply apparatus, when voltages induced from the secondary windings of the transformer 400 are lowered to be one quarter of the induced voltages at a normal mode, the PFC controller 210 is supplied with a voltage lower than a source voltage necessary for a normal operation thereof, so that the PFC circuit 200 does not operate.
PFC circuit 200 includes the PFC controller 210, a switching transistor TR1, a booster transformer T1 for boosting the output voltage of the fullwave rectifier 100 to about 400 Volts! according to the ON/OFF of the switching transistor TR1, a rectifier 230 for rectifying the induced voltage from the booster transformer T1, and a voltage divider 240 for regulating the output voltage of the PFC circuit 200 in accordance with the fluctuation of the input voltage of the PFC controller 210 as well as load variation.
PWM control circuit 300 includes a pulse width modulation (PWM) controller 310, a switching transistor TR2, a resistance R4 for supplying a source voltage of, for example, about 12 Volts! to the PWM controller 310 while the PWM controller 310 is at a start mode thereof, and a capacitor C3.
The primary winding Lp of the transformer 400 is connected between the PFC circuit 200 and the switching transistor TR2 and the windings Ls1˜Ls4 thereof are connected to the rectifiers each which is composed of a resistor and a diode in the output circuit 500. The winding part Ls1 at the secondary side of the transformer 400 has the number of turns enough to provide a first induced voltage V2 which is four times as high as a first source voltage applied to a microcomputer 710 and the winding part Ls2 has the number of turns enough to provide a second induced voltage V3 which is four times as high as a second source voltage applied to the PWM controller 310. An induced voltage through the winding part Ls4 of the transformer 400 is provided to the PFC controller 210 through a rectifier composed of a diode D7 and a capacitor C7.
Output circuit 500 connected with the secondary windings of the transformer 400 generates a variety of voltages such as 5, 8, 13, 25, 50, 90 and 190 Volts!, etc. Those voltages from the output circuit 500 are used to power the operation of the display monitor. For example, the induced voltage through the winding part Ls1 is applied to the regulator 510 through the rectifier composed of a diode D3 and a capacitor C4. The regulator 510 generates a voltage of 5 Volts! to be provided to the microcomputer 710. The induced voltage through the winding part Ls2 is applied to the regulator 520 through the rectifier composed of a diode D4 and a capacitor C5. The regulator 520 generates a voltage to be provided to the PWM controller 310 during the normal mode.
Feedback control circuit 600 is provided to control a feedback current of the PWM controller 310 in accordance with a variation of the induced voltage from the winding part Ls3. The feedback control circuit 600 receives a voltage V4 from the rectifier which is connected with the winding part Ls3 and composed of a diode D5 and a capacitor C6 to allow the feedback current flow to a feedback terminal F/B of the PWM controller 310. The voltage V4 from the rectifier is divided by resistors R5 and R6 which are serially connected with each other and then the divided voltage is applied to a comparator 610. The divided voltage is compared with a reference voltage by means of the comparator 610. The feedback current flowing through a photocoupler 620 to the PWM controller 310 may be varied in amount according to the comparison result of the comparator. If the divided voltage is less than the reference voltage, the comparator 610 generates a high level signal. If the divided voltage is not less than the reference voltage, the comparator 610 generates a low level signal.
In case the voltage V4 is increased above a constant voltage, the output level of the comparator 610 drops down so that a current signal flowing through a photodiode PD1 is increased in amount. As a result, the feedback current flowing through a phototransistor PT1 to the PWM controller 310 is increased in amount and a duty ratio of the output pulse of the PWM controller 310 is reduced. Therefore the induced voltage from the winding part Ls3 can be controlled.
In addition to the microcomputer 710, the DPMS control circuit includes a transistor TR3 and a resistor R8. The microcomputer 710 generates a control signal CS in response to the information regarding a power saving mode from the personal computer PC. If the power supply apparatus is at a normal mode, the microcomputer 710 generates a control signal of low level. Likewise, if the power supply apparatus is at a power-off mode, the microcomputer 710 generates a control signal of high level.
First, during a normal mode, an externally applied AC (alternative current) voltage is converted into a rectified voltage by means of a fullwave rectifier 100. This rectified voltage is applied through the boosting transformer T1 to the rectifier 230 and then charged in the capacitor C2 of the rectifier 230. If the capacitor C2 is fully charged, it has a charged voltage V1 of about 400 Volts!. The voltage V1 is applied through the resistor R4 to the source B+ of the PWM controller 310 and at the same time to the first winding of the transformer 400. If the voltage V1 is increased to be equal to the source voltage of the PWM controller 310, the PWM control circuit 300 starts to operate. Then the PWM controller 310 generates a pulse signal to make the switching transistor TR2 be switched. According to the switching of the transistor TR2, an energy is transmitted from the primary winding Lp of the transformer 400 to the secondary windings Ls1˜Ls4. Supposing that the source voltages of the microcomputer 710 and the PWM controller 310 are 5 Volts! and 12 Volts!, respectively, the induced voltages V2 and V3 from the winding parts Ls1 and Ls2 become about 20 Volts! and 50 Volts!, respectively. This is because each of the winding parts Ls1 and Ls2 has the number of turns enough to obtain the induced voltage being about 4 times as high as the source voltage.
At an early state of the normal mode, the PFC circuit 200 does not operate at all. However, if the PWM control circuit 300 starts to operate and an energy is transmitted from the primary winding Lp to the secondary winding part Ls4, an induced voltage V7 from the winding part Ls4 is applied to the PFC controller 210. The winding part Ls4 has the number of turns enough to obtain the induced voltage V7 equal to the source voltage of the PFC controller 210. Thus, if the source voltage of the PFC controller 210 is 12 V!, the induced voltage V7 of the winding part Ls4 becomes about 12 Volts!. Accordingly, when the PFC circuit 200 starts to operate and generates the output voltage V1 of about 400 Volts!.
Next, during a power-off mode, when the information indicative of a power-off mode are provided from the personal computer, the microcomputer 710 generates a control signal of high level and then the transistor TR3 is turned on in response to the high level control signal. Then the feedback current flowing to the PWM controller 310 is increased in amount so that the duty ratio of the output pulse thereof is more greatly reduced during the power-off mode than during the normal mode. As a result, each of the induced voltages from the secondary winding parts of the transformer 400 is decreased to about one quarter of each of the induced voltages at a normal mode. At this time, since the winding parts Ls1 and Ls2 have the number of turns enough to obtain the induced voltages being about 4 times as high as the source voltages of the microcomputer 710 and the PWM controller 310, respectively, the induced voltages V5 and V6 from the secondary winding parts Ls1 and Ls2 are maintained to be about 5 Volts! and 12 Volts!, respectively. Accordingly, the microcomputer 710 and the PWM controller 310 can be normally operated.
However, because the secondary winding part Ls4 has the number of turns enough to obtain the induced voltage equal to the source voltage of the PFC controller 210, the induced voltage V7 of the secondary winding part Ls4 is rendered to be about 3 Volts! and thereby the operation of the PFC controller 210 is interrupted. Also during the power-off mode, most of components besides the PWM controller 310 and the microcomputer 710 are stopped.
As described above, a power supply apparatus according to the present invention does not require additional circuitry for a DPMS circuit for controlling a power factor correction circuit, and thereby has a simplified power supply for the power factor correction circuit. As a result, production cost of the power supply apparatus may be reduced.
While there have been illustrated and described what are considered to be preferred embodiments of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made, and equivalents may be substituted for elements thereof without departing from the true scope of the present invention. In addition, many modifications may be made to adapt a particular situation to the teaching of the present invention without departing from the central scope thereof. Therefore, it is intended that the present invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out the present invention, but that the present invention includes all embodiments falling within the scope of the appended claims.
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A power supply apparatus for a display monitor includes a power factor correction circuit coupled to receive a primary voltage, for correcting a power factor of said primary voltage and generating a secondary voltage; a switch operable in response to a pulse signal; a switch control circuit for generating said pulse signal; a transformer including a primary winding and secondary windings connected to each other by mutual induction, in which the primary winding has a first terminal coupled to receive the secondary voltage and a second terminal connected to the switch, and in which the transformer is being supplied with primary induced voltage when the pulse signal has a primary duty ratio and supplied with secondary induced voltage lower than the primary induced voltage when the pulse signal has a secondary duty ratio; a rectifier for rectifying the primary and secondary induced voltages; and a smoothing circuit for smoothing an output voltage of the rectifier for application to the power factor correction circuit.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The following co-pending application, Attorney Docket No. 20060042-US-NP, U.S. application Ser. No. ______, filed Aug. — , 2006, titled “Spot Color Controls and Method”, is assigned to the same assignee of the present application. The entire disclosure of this co-pending application is totally incorporated herein by reference in its entirety.
BACKGROUND AND SUMMARY
[0002] This disclosure relates generally to methods and systems for color management in image/text printing or display systems, and more particularly to a system and method for automatically achieving spot color production with consistency and accuracy for a variety of printer configurations.
[0003] To meet customer demand, the commercial printing industry requires the capability of producing spot colors accurately and consistently. Spot colors can be defined as a fixed set of colors which may be Pantone® colors, customer logo colors, colors in a customer's proprietary marked patterns, or customer defined colors in the form of an index color table. Spot colors are often used, or can be used, for large background areas, which may be the most color critical portion of a particular page. Consistent color in these areas may determine the difference between success or failure in meeting customer requirements.
[0004] A goal of the disclosed system and method is to transform the current production print practice by providing an automated approach to the printing of spot colors. Because imaging can occur over a variety of different printing systems and practiced by a variety of different clients and customers, the colors may not always be consistent or accurate. Existing spot color editors utilize a manual approach to the adjustment of CMYK combinations of spot colors prior to raster image processing (RIPing). For example, the document creator may select a Pantone® color for application in specific areas through a user interface on a printing device or computer monitor, such as that available on the Xerox® DocuSP® Controller. The Pantone-provided CMYK combination for the selected printer is obtained from a look-up table. Prior to RIPing the document in the printer, the operator has the option of entering a spot color editor function and specifying an alternative CMYK combination to achieve the desired color. The document is then RIPed and then printed using the spot color editor combinations where specified, and Pantone combinations otherwise.
[0005] This workflow presents various problems, among which is operator error associated with manual adjustments of the CMYK combinations; modifications to the CMYK values may result in more variability from machine to machine. Also, the manually-adjusted CMYK values may require more iterations to achieve the desired color. Due to the manual adjustments it may be difficult for customers to achieve the correct CMYK combinations even after repeated trials. Consequently, a customer has no assurance that the print shop that has been chosen to produce a job can reliably produce the colors as intended, unless every print job is reviewed by a well trained expert who is very familiar with all the capabilities of a given print shop.
[0006] All U.S. patents and published U.S. patent applications cited herein are fully incorporated by reference. The following patents or publications are noted:
[0007] U.S. Patent Application Publication No. 2002/0093684 to Bares et al. (“Accurate Printing of Proprietary Mark Patterns and Colors”) describes a printing system that provides a dictionary of recognizable patterns and defined colors corresponding to proprietary marks and selected colors. The dictionary is linked to a user interface on which a user may designate a location within a document and one or more of the proprietary marks with defined colors from an accessible menu. A processor associates the defined colors with the image at the specified location and generates a printer signal representative of the colors and image. Alternatively, the processor may include a pattern recognizer for identifying recognizable patterns within a document. Those patterns having a likeness to defined patterns within the pattern dictionary can be converted to the defined patterns for display or imaging.
[0008] U.S. Pat. No. 6,157,469 to Mestha (“Dynamic Device Independent Image Correction Method and Apparatus”) describes a method of controlling color drift between a desired image and an output image as obtained by a marking device and intended to match the desired image. The method includes detecting a current output color in the output image with a color sensing device, determining a difference between the current output color in the output image and a corresponding color in the desired image, and automatically setting a next output color in the output image equal to a corrected color that minimizes the difference between the next output color and the corresponding color in the output image.
[0009] U.S. Pat. No. 6,178,007 to Harrington (“Method for Continuous Incremental Color Calibration for Color Document Output Terminals”) teaches a method for continuously upgrading the color calibration for an electrophotographic printer using a color transform look up table stored in memory. A single or small number of color patch samples is printed at regular intervals during the use of the printing machine. The color patches are sensed and a determination made as to the difference between the sensed color and the desired color. A corrective color calibration value is determined for the sensed patch and a correction is made for that color in the printer memory. The process is repeated to assure that all of the colors within the gamut of the machine are continuously updated.
[0010] U.S. Pat. No. 6,744,531 to Mestha et al. (“Color Adjustment Apparatus and Method”) teaches an apparatus for providing consistent output across a plurality of different hard copy output devices which may be included in a system having an image data source and a hard copy output device. The image data source supplies image data to a printable image data adjusting apparatus. The image data supplied may be in a device-dependent color space or a device-independent color space. For image data in a device-dependent color space, the adjusting apparatus first converts the image data into device-independent image data and stores it in memory as target image data. If the image data is already device-independent, the image data are stored in the memory of the adjusting apparatus as target image data. The printable image data adjusting apparatus then uses the target image data to generate printable image data. The hard copy output device uses the printable image data to generate a hard copy image. The hard copy image is then passed within the optical field of a sensor that detects device-independent image data values of the hard copy image. The detected device-independent image data values are then compared against the target image data to generate color adjustment factors. The color adjustment factors are used to produce a hard copy image having detected device-independent image data values that more closely represent the target image data.
[0011] U.S. Pat. No. 7,069,164 to Viturro et al. (“Method for Calibrating a Marking System to Maintain Color Output Consistency Across Multiple Printers”) teaches a method for maintaining consistent color output across printers even when the inline sensors have differences in accuracy due to various technical and environmental factors. A spectrophotometer is used to measure the color quality of printed references. Adjustments are then iteratively made until reference charts of desired color quality are obtained. The printed reference allows one to achieve relatively high system performance by removing sensor inaccuracies. Using the printed reference measured by the inline sensor, control systems of each machine are calibrated. At customer sites and at suitable intervals, a reference document can be read using the inline sensor on a reference machine and any differences from expected values can be calibrated out.
[0012] U.S. Patent Application Publication No. 2005/0030560 to Maltz et al. (“Methods and Systems for Controlling Out-of-gamut Memory and Index Colors”) describes methods and systems in an image processing device for controlling colors that are located external to a gamut. A plurality of color values can be automatically provided as input to said image processing device, wherein the image processing device is under the control of a particular dimensional order, typically a three-dimensional order, but alternatively can be a two-dimensional order. An operation can then be performed dynamically determining which color value among the plurality of color values has attained a gamut limit. Thereafter, the particular dimensional order can be automatically reduced, providing improved control for colors that are located external to the gamut. The plurality of color values analyzed is generally associated with three colors: cyan, magenta, and yellow.
[0013] The disclosed embodiments provide examples of improved solutions to the problems noted in the above Background discussion and the art cited therein. There is shown in these examples an improved method for enabling accurate and consistent imaging of selected colors within a document for various printing device configurations utilizing an automated spot color editor. The method includes determining appropriate target values for a selected color within a print job. The selected color may be described as being within a color space such as reflectance spectra, L*a*b*, XYZ, LHC, CMYK, RGB, sRGB, parameters describing color or a color number. The automated spot color editor modifies or adjusts the selected color by selecting a quality level, in the form of a color difference metric, and a maximum number of iterations, which is the maximum number of times the automated spot color editor is operated to calculate a CMYK color formula. Sample patch(es) are printed and analyzed for the selected target value and a CMYK color formula based on the color composition of the sample patch is calculated. The CMYK color formula is inserted into a spot color editing table. Through a graphical user interface, an operator may review the color formula for acceptance.
[0014] In an alternate embodiment there is disclosed a system for utilizing an automated spot color editor for enabling accurate and consistent imaging of selected colors within a document for various printing device configurations. The spot color editor determines appropriate target values for a selected color within a print job. The selected color exists within a color space, which may include reflectance spectra, L*a*b*, XYZ, LHC, CMYK, RGB, sRGB, parameters describing color or a color number. To modify or adjust the selected color, the spot color editor selects a quality level in the form of a color difference metric and a maximum number of iterations to be performed to calculate a CMYK color formula. A sample patch for the selected target value is printed and the color composition of the sample patch is analyzed. After a CMYK color formula based on the color composition of the sample patch is calculated, the CMYK color formula is inserted into a spot color editing table. An operator may indicate acceptance of the color formula through a graphical user interface.
[0015] In yet another embodiment there is disclosed a computer-readable storage medium having computer readable program code embodied in the medium which, when the program code is executed by a computer, causes the computer to perform method steps for enabling accurate and consistent imaging of selected colors within a document for various printing device configurations utilizing an automated spot color editor. The method includes determining appropriate target values for a selected color within a print job. The selected color may be described as being within a color space such as reflectance spectra, L*a*b*, XYZ, LHC, CMYK, RGB, sRGB, parameters describing color or a color number. The automated spot color editor modifies or adjusts the selected color by selecting a quality level, in the form of a color difference metric, and a maximum number of iterations, which is the maximum number of times the automated spot color editor is operated to calculate a CMYK color formula. Sample patch(es) are printed and analyzed for the selected target value and a CMYK color formula based on the color composition of the sample patch is calculated. The CMYK color formula is inserted into a spot color editing table. Through a graphical user interface, an operator may review the color formula for acceptance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The foregoing and other features of the embodiments described herein will be apparent and easily understood from a further reading of the specification, claims and by reference to the accompanying drawings in which:
[0017] FIG. 1 is a functional block diagram of one exemplary embodiment of a print system in accordance with the automated spot color editor;
[0018] FIG. 2 is a flowchart outlining one exemplary embodiment of the method of operation of the automated spot color editor;
[0019] FIG. 3 is a flow chart outlining one exemplary embodiment of the automatic determination of the presence of spot colors in a print job prior to printing for use with the automated spot color editor; and
[0020] FIG. 4 is a flow chart outlining one exemplary embodiment of a method for creation of a new spot color for use with the automated spot color editor.
DETAILED DESCRIPTION
[0021] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific illustrative embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that logical, mechanical and electrical changes may be made without departing from the scope of the disclosure. The following detailed description is, therefore, not to be taken in a limiting sense.
[0022] The automated spot color editor improves upon the existing methods for adjusting or developing CMYK combinations to achieve consistency and accuracy in the print production of spot colors. The spot color editor provides an automated process under closed-loop control, based on Pantone-defined or customer-defined target values. The editor determines the appropriate target values for the desired customer colors and then activates the Automated Spot Color Editor (ASCE), which utilizes various functionality to achieve consistent customer selectable colors. The ASCE prints a target patch(es) using the desired target values, measures the color of the printed patch using a color sensor such as an in-line spectrophotometer, calculates the CMYK combination based on the measurement, and inserts the resultant CMYK combination into a Spot Color Editing table. Additionally, the operator may be provided with the ability to accept the resultant CMYK combination or make adjustments manually. Optionally, a preflight review of the submitted job may be performed to automatically determine whether spot colors are present in the submitted print job.
[0023] Various computing environments may incorporate capabilities for supporting a network on which the automated spot color editor may reside. The following discussion is intended to provide a brief, general description of suitable computing environments in which the method and system may be implemented. Although not required, the method and system will be described in the general context of computer-executable instructions, such as program modules, being executed by a single computer. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types. Moreover, those skilled in the art will appreciate that the method and system may be practiced with other computer system configurations, including hand-held devices, multi-processor systems, microprocessor-based or programmable consumer electronics, networked PCs, minicomputers, mainframe computers, and the like.
[0024] The method and system may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communication network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices.
[0025] Referring to FIG. 1 , there is depicted a functional block diagram of one example embodiment of a print color adjustment system in accordance with the automated spot color editor disclosed herein. It is to be understood that certain aspects of the system would operate in accordance with pre-programmed instructions used to operate a local or networked computer system to carry out such features—perhaps on a plurality of interconnected computers at a time. Such a system might include a commercially available personal computer with appropriate graphics rendering capability that can also be associated with a networked storage medium or similar memory device wherein the system is accessible, perhaps via an Internet or intranet for submission of print jobs. It is also contemplated that one or more aspects of the system may be implemented on a dedicated computer workstation. As shown in FIG. 1 , print color adjustment system 100 is connected to an image data source 110 , and includes color adjustment subsystem 130 , a hard copy output device 150 , and an image sensor 180 . These devices are coupled together via data communication links 120 , 140 , 160 , and 170 . These links may be any type of link that permits the transmission of data, such as direct serial connections, a local area network (LAN), wide area network (WAN), an intranet, the Internet, circuit wirings, and the like.
[0026] The content for a printing job is initially provided by the customer through an image data source 110 in a form acceptable to the system. The image data source may be a personal computer, a microprocessor, a scanner, a disk drive, a tape drive, a hard disk, zip drive, CD-ROM drive, a DVD drive, a network server, a print server, a copying device, or any other known or later developed device or system that is able to provide the image data. Image data source 110 may include a plurality of components including displays, user interfaces, memory, disk drives, and the like. For simplicity of the following disclosure, it will be assumed that the image data source is a personal computer although, as indicated above, the image data source is not limited to a personal computer.
[0027] Hard copy output device 150 may be any type of device that is capable of outputting a hard copy of an image and may take the form of a laser printer, a bubble jet printer, an ink jet printer, a copying machine, or any other known or later developed device or system that is able to generate an image on a recording medium using the image data or data generated from the image data. The hard copy output device 150 generates the hard copy of the image based on printable image data generated by the color adjustment subsystem.
[0028] Image sensor 180 may be any type of device that is capable of detecting image data from a hard copy image and supplying the image data as detected device-independent image data or post-processed image data, which may be in device-independent or in device-dependent form to the color adjustment subsystem 130 . For example, the image sensor may be an optical sensor, a spectrophotometer, a color sensor, or any other known or later developed device or system that is able to measure the color values of the image data from the hard copy image output by the hard copy output device 150 .
[0029] Although for the purposes of description color adjustment system 100 is shown as a separate device from the image data source 110 , the color adjustment system 100 may be an integrated device, such as a digital copier, a computer with a built-in printer, or any other integrated device that is capable of producing a hard copy image output. With such a configuration, for example, the image data source 110 , the color adjustment subsystem 130 , the hard copy output device 150 , and the sensor 180 may be contained within a single device.
[0030] Alternatively, the color adjustment system 100 may be a separate device containing the color adjustment subsystem 130 and the sensor 180 attachable upstream of a stand-alone hard copy output device 150 . For example, the color adjustment subsystem 130 and the sensor 180 may be a device which interfaces with both the image data source 110 and one or more hard copy output devices 150 , as would be the case if the color adjustment system 100 is incorporated into a network print server that manages printer data for a plurality of the same or different printing devices.
[0031] Furthermore, the color adjustment system 100 may be implemented as software on the color adjustment subsystem 130 or the image data source 110 . The image sensor 180 may be incorporated into the printer 150 or may exist as a stand alone device that communicates the detected data back to the image data source 110 . Other configurations of the elements shown in FIG. 1 may be utilized without departing from the spirit and scope of the specification and claims herein.
[0032] The term “image”, as used in this disclosure refers to a graphic or plurality of graphics, compilation of text, a contone or haftone pictorial image, or any combination or subcombination thereof, that is capable of being output on a display device, a marker and the like, including a digital representation of such image. For example, an image may be a combination of graphics, text and pictures that is represented by a series of pixel values denoting the color, intensity, etc., of the particular pixels that make up the image. A special subclass of images is images associated with complete documents, which are hereinafter referred to as “document images”. Thus an image may be a document image assembled by a customer at the image data source 110 , one or more elements of a document image, a “test patch” generated by printing application software or another type of control system, or a member of a collection of images in a database. Image data source 110 provides image data that, when used to display the image or convert the image into a hard copy, provides an approximate representation of the image. The image data source 110 provides the image data to the color adjustment system 100 .
[0033] The image data input to the color adjustment subsystem 130 may be in either a device-dependent color space or a device-independent color space. For example, if the image data source 110 is a personal computer, the image data used for representing the image is typically in the RGB color space, since this is the color space used by a display of the image data source 110 . These RGB values may be directly forwarded to the color adjustment subsystem 130 or may undergo conversion into a device-independent color space, such as L*a*b*, (the Commission Internationale de L'éclairage color standard) prior to being input to the color adjustment subsystem 130 . L* defines lightness, a* corresponds to the red/green value, and b* denotes the amount of yellow/blue, which corresponds to the way the human eye perceives color. A neutral color is a color for which a*=b*=0.
[0034] If the conversion of the device-dependent color space values into device-independent color space values is not performed by the image data source 110 when inputting the image data to the color adjustment system 100 , then the color adjustment system 100 may perform the conversion between the color spaces.
[0035] The color adjustment subsystem 130 transforms the device-independent image data into printable image data based on the color space used by the hard copy output device 150 . For example, if the hard copy output device 150 is a printer, the color space used by the printer will often be the CMYK color space. In such a case, the color adjustment subsystem 130 converts the device-independent image data into CMYK-color space printable image data for the appropriate target value. Alternatively, the target values may be described in any of the color spaces L*a*b*, CMYK, RGB or sRGB or even the color number, such as a Pantone® number.
[0036] Because of various factors, such as environmental conditions, use patterns, the type of media used, variations in media, variations from original models used in initializing the hard copy output device, general wear, and the like, the colors capable of being output by the hard copy output device 150 may not match the desired colors represented by the device-independent image data.
[0037] In the color adjustment system, when a hard copy of the image is output by the hard copy output device 150 , the hard copy is placed within the field of detection of the image sensor 180 . Image sensor 180 generates image data from the hard copy image and transmits this image data in any of the device independent color coordinate spaces (reflectance spectra, L*a*b*, XYZ, LHC) or in device dependent spaces (CMY, CMYKL, RGB, sRGB) depending on the direct output or transformed output of the sensor image data to the color adjustment subsystem 130 .
[0038] The color adjustment subsystem 130 compares the detected image data values with target image data stored in memory. Based on the comparison, adjustment factors are determined that adjust the printable image data to create a revised color combination for the target value such that the resulting image output by the hard copy output device 150 results in detected image data values that more closely correspond to the target image data. Alternatively, color adjustment subsystem may be utilized to develop new spot colors to meet customer demands and these new spot color combinations are stored in memory.
[0039] This process may be repeated a number of times until an amount of error between the detected image data and the target image data falls within an acceptable tolerance. The process may also be restricted to a preset number of iterations. Once the detected image data is within the given tolerances, and/or the maximum number of iterations has been performed, the color adjustment subsystem 130 provides the hard copy output device 150 with the final set of printable image data usable to output the final image. In this way, the final image will more closely resemble the desired output image regardless of the particular hard copy output device that produces the final image. Thus, if the same image is to be printed by a plurality of different hard copy output devices having different attributes or different printer drifts, substantially the same final image will be produced by each hard copy output device regardless of the different attributes and drifts of each printing device.
[0040] The particular methods performed by the spot color adjustment comprise steps which are described below with reference to a series of flow charts. The flow charts illustrate an embodiment in which the methods constitute computer programs made up of computer-executable instructions. Describing the methods by reference to a flowchart enables one skilled in the art to develop software programs including such instructions to carry out the methods on computing systems. The language used to write such programs can be procedural, such as Fortran, or object based, such as C++. One skilled in the art will realize that variations or combinations of these steps can be made without departing from the scope of the disclosure herein.
[0041] Turning now to FIG. 2 , a flowchart illustrates an exemplary embodiment of the method of operation of the automated spot color editor. At 210 the spot color editor determines the appropriate target values for customer colors. The target values can be described in several forms for spot colors. For example, the target values can be in any of the following color spaces: reflectance spectra, L*a*b*, CMYK, RGB, sRGB, parameters describing color, or even the color number. If color numbers are used, the target values are determined via offline experiments. Such experiments would include 1) creating a test pattern with the spot color of interest, 2) printing the pattern on the printer of interest, 3) transporting the pattern for measurements (through the paper path for inline and carrying paper manually for offline measurements), 4) measuring the printed pattern with a color sensor and 5) storing the sensor output to a target log file. For inline measurements, the printer should have an input path for moving the printed pattern in the paper path.
[0042] The sensor output may be in any of the device independent color coordinate spaces (reflectance spectra, L*a*b*, XYZ, LHC) or in device dependent spaces (CMY, CMYK, RGB, sRGB) or parameters that succinctly distinguish color (for example, parameters {p 1 , p 2 , p 3 , . . . etc.} used to describe color) depending on the direct output or transformed output of the sensor. Also, the offline/inline experiments may be conducted to determine target values when color matching is required to a hard copy proof. Inline or offline sensors can also be used to obtain the color values of the targets for the hardcopy proofs. The ASCE provides an approach to capture a color value using a spot measurement of the hard copy sample. The approach includes (1) transporting the proof for measurements (through the paper path for inline and carrying proof manually for offline measurements), (2) initiating color sensor measurements to correctly measure the proof, (3) measuring the spot color area of interest in the proof with a color sensor and storing the sensor output to a target log file with a unique spot color identifier. For inline measurements from the proof, the printer should have an input path for moving the printed proof in the paper path while printing process mode is disabled (development, fusing, etc.). In another embodiment, the customer is able to adjust or enter the target values manually. Alternatively, the target colors can be obtained via menu links to the identified designations. The target table may also be a hypertext link to a remote networked site where the target values are adequately defined and labeled. These values may also be obtained using known formulae. The unique spot color identifier is used for the target values so that it matches with the color target names in the document that is to be RIP'ed with the new CMYK combination.
[0043] To activate the ASCE function at 220 , a software button on the user interface is utilized. When the customer activates the ASCE, control system prints a target patch set using the desired target values developed at 210 or any other modified target values as required by the control algorithm depending on the spot colors. If the customer/operator is not satisfied with the printed spot colors in the test patch, this step would involve repeated iterations of the ASCE. The spot color control algorithms described in U.S. Patent Application Publication No. 2005/0030560 to Maltz et al. (“Methods and Systems for Controlling Out-of-gamut Memory and Index Colors”) and U.S. Pat. No. 6,744,531 to Mestha et al. (“Color Adjustment Apparatus and Method”), both hereby incorporated by reference in their entirety, remove the manual color adjustment step and hence can identify the right CMYK combination without distorting other or neighborhood colors in the document. After the iterations are completed, ASCE finds the required CMYK combination for the chosen target values from 210 . For determination of the number of iterations to be performed, the algorithm itself may identify the number of iterations required to find the required CMYK combination for the spot colors based on the criteria stored inside the algorithm. One such criteria would be the mean deltaE, where deltaE is the color difference metric, a value based on the Euclidian distance (the shortest line in 3D) between the coordinates of the reference and sample used to measure the color difference between target values (when target values are stored in terms of L*a*b*) and the measured values for all the spot colors of interest. DeltaE2000 is another perceptual based color difference metric just starting to be used in printing industry.
[0044] At 230 , the operator can then decide to accept the CMYK combinations into the document where the spot color tag/name links the combinations to particular spot colors. The acceptability criteria may be based on visual inspection of a proof copy with printed color or simply the mean deltaE value. The customer then RIPs the image containing new CMYK values for printing.
[0045] Turning now to FIG. 3 , the flow chart illustrates an example embodiment for the automatic determination of the presence of spot colors in a print job prior to printing for use with the automated spot color editor. While the spot color editor as described with respect to FIG. 2 automates workflow for modifying or adjusting CMYK values to achieve consistency and repeatability, it is still not fully automatic since the user has to define the spot color manually. To further automate the procedure, minimize the human error in correcting spot colors, and decrease the time needed to adjust spot colors, the images may be checked automatically after they are submitted but prior to being printed in a preflight step. The preflight step provides detection of the presence of spot colors in a submitted print job and activation of the automated spot color editor to correct for all spot colors found in the search procedure in each customer file. This automation would decrease the time needed to run ASCE and help to improve the accuracy and repeatability of spot colors in customer files.
[0046] At 310 a customer file is loaded on the printer and released for printing. At 320 a determination is made as to whether the queue level/job ticket feature “Run ASCE automatically” is set to “ON”. If the “Run ASCE automatically” feature is not activated, the Image processing computer RIPs the file and sends the image to the marking device. If the “Run ASCE automatically” feature is activated, a quality level similar to deltaE criteria and iteration number as described hereinabove is selected at 340 . The image file is reviewed at 350 to detect the presence of any spot colors. The spot color detection routine looks for any standardized document convention describing the use of spot colors, and their names (as one example, names standardized by Pantone Inc.), in the document. For example, if the customer image is in PostScript® format, the comment %%DocumentCustomColors indicates the use of custom (spot) colors in the document. Any application written in the Image Processing computer names these colors and their CMYK or RGB approximations through the %%CMYKCustomColor or %%RGBCustomColor comments in the body of the document. Table 1 below provides an example of a PostScript document with Pantone spot colors and comments describing the Pantone colors.
[0000]
TABLE 1
%!PS-Adobe-3.0 EPSF-3.0
%%Creator: Adobe Illustrator(R) 8.0
%%AI8_CreatorVersion: 8
%%For: (John Stanzione) (Spot Color Source)
%%Title: (solid to process.eps)
%%CreationDate: (5/24/01) (1:02 PM)
%%BoundingBox: 0 0 0 0
%%HiResBoundingBox: 0 0 0 0
%%DocumentProcessColors:
%%DocumentSuppliedResources: procset Adobe_level2_AI5 1.2 0
%%+ procset Adobe_ColorImage_AI6 1.3 0
%%+ procset Adobe_Illustrator_AI5 1.3 0
%%+ procset Adobe_cshow 2.0 8
%%+ procset Adobe_shading AI8 1.0 0
%AI5_FileFormat 4.0
%AI3_ColorUsage: Black&White
%AI3_IncludePlacedImages
%AI7_ImageSettings: 1
%%CMYKCustomColor: 0 0 0.51 0 (Color name)
%%+ 0 0 0.79 0 (Color name)
%%+ 0 0 0.95 0 (Color name)
%%+ 0 0.03 1 0.38 (Color name)
%%+ 0 0.03 1 0.6 (Color name)
%%+ 0 0.07 1 0.5 (Color name)
%%+ 0 0.02 0.81 0 (Color name)
%%+ 0 0.04 0.62 0 (Color name)
%%+ 0 0.02 0.95 0 (Color name)
.
.
.
[0047] As can be seen in Table 1, “%%CMYKCustomColor” provides an approximation of the custom color (spot color) CMYK values specified by the ‘color name’ in parentheses. Four components of cyan, magenta, yellow, and black are specified as numbers from 0 to 1 representing the percentage of that process color. The Document Structuring Convention allows continuation lines starting “%%+”, so to find additional colors, the detection routine examines lines starting with “%%CMYKCustomColor” and lines immediately following such a line that begin with “%%+”.
[0048] Alternatively, an approach such as that described in U.S. Pat. No. 6,456,395 to Ringness (“Method for Separating Colors of Encapsulated Postscript Images”), which describes some methods of spot color sniffing from an EPS file is also applicable. Ringness teaches a method for mapping objects (e.g., Pantone Red, Pantone Red 100, etc.) having object colors to the intended spot-color plate for offset printing. For example, to map Pantone Red in one EPS file to Pantone Red 100 in another EPS file, which together was meant to produce the same Pantone Red on the same spot-color plate. Instead of performing the color separations manually, a software utility is created for separating object colors in an EPS file and then mapping the objects to the appropriate spot-color partitions. A utility called Encapsulated POSTSCRIPT Color Separation (ECS) is proposed to perform this function.
[0049] A determination is made at 360 as to whether the image file contains spot colors. If no spot colors have been identified in the image file, the image processing computer RIPs the file and sends the image to the marking device. If spot colors are present, the spot color editor is activated automatically at 370 . The spot color editor may run while another job is printing, or the print job may be “held” until the current print job in process completes. The advantages of running spot color editor automatically include reduction of the effects of long term engine drift and spot color stability observed in customer prints, time savings (the customer no longer needs to manually start the spot color editor from the image processing computer and include a newly calculated CMYK combination after clearing acceptance criteria manually), reduced operator error, and no required operator intervention.
[0050] Turning now to FIG. 4 , the flow chart illustrates an example embodiment of a method for creation of a new spot color for use with the automated spot color editor. When an operator manually starts the spot color editor from the image processing computer graphical user interface, a default list of colors is available that is the same as the last time the spot color editor was run manually. The operator selects a quality level, which includes the color specifications (for example dE2000) and maximum number of iterations for the spot color editor. The operator then launches the image processing computer tool to create a new spot color at 410 . The operator enters a name for the spot color at 420 and queries whether “create spot color from hard copy sample” has been selected from the graphical user interface at 430 . If the spot color will not be created from a hard copy sample, the operator enters the new spot color values for CMYK at 440 . For example, a specific Pantone color would be characterized with the unique values for CMYK that define the specific color. The spot color dictionary is updated at 445 with the new color information.
[0051] If the spot color is to be created from a hard copy sample, the operator is prompted to load the sample under the color sensing device such as a XRITE DTP41 Spectrophotometer sensor or inline spectrophotometer sensor following the supplied placement instructions at 450 . The inline spectrophotometer sensor may be located in the print engine output paper path with a cable connected to a processor board. The processor board would then be connected to the image processing computer, either directly or through other processing boards. The operator loads the sample at 460 and informs the image processing computer when the sample is in the correct location at 460 . The image processing computer transmits spot read commands to the color sensing device at 470 . The image processing computer calls the spot color editor at 480 to calculate the CMYK values for the new spot color based on the color (e.g., L*a*b*) measurements made by the color sensing device. The measured color (e.g., L*a*b*) values are stored in the spot color editor module to use as the reference for this spot color at 490 . The spot color dictionary is then updated with the new spot color at 495 .
[0052] While the present discussion has been illustrated and described with reference to specific embodiments, further modification and improvements will occur to those skilled in the art. For example, the system and method described in Attorney Docket Number 20060042-US-NP, U.S. application Ser. No. ______, filed Aug. — , 2006, titled “Spot Color Controls and Method”, may be utilized to perform the ASCE function. Additionally, “code” as used herein, or “program” as used herein, is any plurality of binary values or any executable, interpreted or compiled code which can be used by a computer or execution device to perform a task. This code or program can be written in any one of several known computer languages. A “computer”, as used herein, can mean any device which stores, processes, routes, manipulates, or performs like operation on data. It is to be understood, therefore, that this disclosure is not limited to the particular forms illustrated and that it is intended in the appended claims to embrace all alternatives, modifications, and variations which do not depart from the spirit and scope of the embodiments described herein.
[0053] It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims. Unless specifically recited in a claim, steps or components of claims should not be implied or imported from the specification or any other claims as to any particular order, number, position, size, shape, angle, color, or material.
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Provided is a method for enabling accurate and consistent imaging of selected colors within a document for various printing device configurations utilizing an automated spot color editor. The method includes determining appropriate target values for a selected color within a print job. The automated spot color editor modifies or adjusts the selected color by selecting a quality level, in the form of a color difference metric, and a maximum number of iterations, which is the maximum number of times the automated spot color editor is operated to calculate a CMYK color formula. Sample patch(es) are printed and analyzed for the selected target value and a CMYK color formula based on the color composition of the sample patch is calculated. The CMYK color formula is inserted into a spot color editing table. Through a graphical user interface, an operator may review the color formula for acceptance.
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BACKGROUND OF THE INVENTION
The present invention relates to a sample heating holder used for an electron microscope by which a sample is heated in the electron microscope to observe change in the sample caused by heating.
As a conventional sample heating holder, Japanese Utility Model Application Laid-Open No.58-173159 discloses a type of sample heating holder which fixes a sample in a heating furnace. Thickness of the heating furnace type sample heating holder is increased by a thickness corresponding to the heating furnace. Further, a high melting point metal of platinum is often used for the sample table for fixing a sample.
On the other hand, a type of sample heating holder other than the heating furnace type is disclosed, for example, in Japanese Patent Application Laid-Open No.6-44936. The sample heating holder uses a heater which is wound in a coil-shape and placed horizontally. A sample is heated by directly placing inside the coil, or a finely powdered sample is heated by directly sprinkling it on the heater. In this case, the sample can be heated up to high temperature with small electric current. In addition to this, since the sample heating holder is of a direct heating type and the sample and the heater are small in size, it is possible to obtain a desired constant temperature in a short time from starting of heating and to perform high resolution observation at high temperature. Further, since the sample heating holder has no structure preventing detection of an X-ray in energy dispersive X-ray (hereinafter, referred to as “EDX”) analysis, it is possible to perform the EDX analysis under room temperature. The heater is detachable.
A sample heating holder using a flat ceramic heater as the heater is disclosed in Japanese Patent Application Laid-Open No.6-68828. In this case, the sample heating temperature is approximately 200° C., and the sample table has abi-axial or double tilting mechanism.
However, the sample heating holder of heating furnace type described above has problems in that the time required to transfer heat to the sample is long because of indirect heating and in that the sample is melt-fixed onto the sample table by heating. Further, the sample heating holder is of the structure setting the sample on the bottom portion of the heating furnace, and therefore EDX analysis of the sample is not taken into consideration. Furthermore, there is a limitation in the heating temperature. On the other hand, the above-mentioned sample heating holder of the type of directly placing the sample on the coil has a limitation that the sample needs to be formed in powder or in a ribbon-shape. The above-mentioned sample heating holder using the flat ceramic heater has problems in that the time required to heat up and stabilize temperature constant is long and in that there is a limitation in the heating temperature.
Catalysts, materials for thermal plant or nuclear plant and so on require material property at a high temperature above 1000° C. or structural analysis in the atom level in order to investigate a process of change in the material property. However, it is difficult to observe the process of change in the material property by the conventional technologies described above. Therefore, each of samples of a material treated at various temperatures is formed in a thin film for electron microscope observation to perform analysis for each treatment temperature.
By checking whether or not the change in the process in the thin film state agrees with a change in the process of heating the material in a bulk state under the same heating condition, it is possible to check whether or not a phenomenon produced in a thin film sample agrees with that in an actual material. However, in the conventional technology, in order to repetitively mill a bulk portion of a single sample after heating, it is required to extract the sample by detaching heaters attached onto the upper side and the downside of the sample and to perform milling by setting the sample to a holder for a focused ion beam (hereinafter, referred to as “FIB”) milling apparatus. Therefore, since the material becomes brittle by heating, the sample is probably damaged at handling to lose a position to be observed.
SUMMARY OF THE INVENTION
The present invention aims at solving such problems in the conventional technology. An object of the present invention is to provide a sample heating holder for electron microscope which can suppress sample drift caused by heating in a short time irrespective of a shape of the sample, and can perform high resolution observation of a sample heated up to a temperature above 1000° C. with small electric current. Further, another object of the present invention is to provide a sample heating holder for electron microscope and a method of observing a sample using the sample heating holder by which after observing a sample under a heating condition, re-milling of a bulk portion of the same sample using an FIB milling apparatus and re-observation of the bulk portion of the same sample using the electron microscope can be performed. Accordingly, observation of an inner bulk portion of the sample under a heating condition and verification by comparing it with a thin film portion can be performed.
The inventors of the present invention fabricated a prototype of a sample heating holder having a structure that a high melting point metal wire coated with a ceramic on the outer surface was used as a heating heater, and an upper surface and a lower surface of a sample were brought directly in contact with the heater. This prototype holder could be directly heated up to approximately 1800° C. However, it was founded that a problem of sample drift caused by thermal expansion of the heater newly occurred. In the high resolution observation in the atomic level, a lattice image of 0.1 to 0.5 nm interval generally needs to be identified, but the required time that the sample reached a thermal equilibrium state in a high temperature and stabilized in a condition capable of performing high resolution observation was long. In addition, there was a problem in that the heating efficiency was low because of heat loss from the sample by thermal dissipation.
The present invention is a result of such a study by which it is found that by attaching a thermally and electrically insulating heater envelope having a carbon coating on the surface around a heater surrounding a sample of a sample heating holder for electron microscope, the thermal expansion at heating and the thermal dissipation can be prevented, and stability of the sample at high temperature can be obtained in a short time.
Further, the other object can be attained by that openings for introducing an FIB are formed in a side surface portion of the heater envelope of the sample heating holder and in a side surface portion of the holder so as to mill the sample by the FIB. The sample heating holder mounted with the sample which has been observed under a heating condition, as it is, is set in an FIB milling apparatus to mill the un-milled bulk portion of the sample through the openings. After milling, the sample heating holder mounted with the milled sample is again set in the electron microscope to observe the sample. Thus, observation of an inside of the bulk portion under a heating condition and verification by comparing it with a thin film portion can be performed.
That is, a sample heating holder for electron microscope in accordance with the present invention is characterized by comprising a holder main body; a heater for heating a sample by directly contacting with the sample; and a thermally and electrically insulating heater envelope for preventing dissipation of heat by covering the heater, wherein the heater envelope has a carbon coating on a surface, and the heater is fixed to the heater envelope.
The heater envelope has a function to improve the heat efficiency, and a function to fix and fasten the heater, that is, a function to prevent the sample draft caused by thermal expansion of the heater. From the viewpoint of heat resistance and low thermal expansion coefficient, it is preferable that the heater envelope is made of a ceramic. In order to provide the heater envelope with the function to improve the heat efficiency by preventing heat dissipation from the heater, it is not always necessary that the heater envelope completely covers the heater from all the directions. Fixing of the heater to the heater envelope can be performed, for example, using a high temperature thermosetting liquid inorganic heat resistant adhesive. By fixing the sample to the heater using a high temperature thermosetting liquid inorganic heat resistant adhesive, the effect of preventing the sample drift can be further improved.
Further, by coating the heater envelope with carbon through a vapor deposition method or the like, it is possible to prevent the heater envelope from charging up by giving electric conductivity to the heater envelope, and it is also possible to prevent occurrence of noise from the heater envelope due to scattered electrons incident to the heater envelope in EDX analysis at room temperature.
By rotatably attaching the heater envelope to the holder main body, it is possible to form a bi-axial or double tilting mechanism by combining with rotation around an axis of the holder main body in the lateral direction and, therefore, to vary an orientation of a crystal to be observed. In addition, it is preferable that the heater envelope is detachable to the holder main body.
The heater envelope has necessary openings such as an opening for letting an electron beam pass through, an opening for extracting a X-ray emitted from the sample by irradiation of the electron beam and an opening for loading and unloading the sample. The opening may be any shape such as a hole-shape, or a notch shape extending from a free edge portion of the heater envelope. Through the openings formed in the heater envelope, it is possible to perform electron microscopic observation or X-ray analysis of a sample, and it is also possible to take out the sample after performing heating, observation or analysis.
The heater envelope may comprise an opening for letting a focused ion beam for milling the sample pass through in a side surface portion. By such a heater envelope, the heater envelope having a sample fixed to the inner heater is extracted from the holder main body and fixed to a holder of an FIB milling apparatus, and then a bulk portion of the sample can be milled by letting an FIB entering through the opening formed in the side surface portion of the heater envelope.
Further, the heater envelope may comprise an opening for letting a focused ion beam for milling the sample pass through in a side surface portion, and the holder main body may comprise an opening at a position overlapping with the opening formed on the side surface of the heater envelope. By such a sample heating holder, the heater envelope having the sample fixed inside is extracted together with the holder main body from the electron microscope and set in the FIB milling apparatus, and an un-milled bulk portion of the sample can be milled by irradiating an FIB on the sample through the opening of the holder main body and the opening at the side surface portion of the heater envelope overlapping with the opening of the holder main body. After finishing milling of the sample, by extracting the holder attached with the heater envelope from the FIB milling apparatus and setting it to the electron microscope, microscopic observation of the milled bulk portion of the sample can be performed.
A method of observing a sample according to the present invention is characterized by a method using the sample heating holder for electron microscope comprising the heater envelope having an opening for FIB milling or the sample heating holder for electron microscope comprising the openings formed in both of the heater envelope and the holder main body described above, which comprises the steps of observing a sample fixed to and heated by the heater of the sample heating holder using an electron microscope; extracting the sample heating holder for electron microscope from the electron microscope and milling an un-milled bulk portion of the sample using a focused ion beam milling apparatus without detaching the sample from the heater; and loading the heater of the sample heating holder for electron microscope holding the milled sample to the electron microscope and observing the portion of the sample milled in the above step using the electron microscope. Fixing of the sample to the heater can be performed using a high temperature thermosetting liquid inorganic heat resistant adhesive.
According to the sample heating holder in accordance with the present invention, high resolution observation of a sample at a high temperature above 1000° C. by suppressing sample drift by heating in a short time and with small electric current. Further, according to the method of observing a sample in accordance with the present invention, a phenomenon occurring in a thin film portion can be verified by comparing it with a phenomenon occurring in a bulk portion re-observation.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is an exploded perspective view showing an example of an front end portion of a sample heating holder in accordance with the present invention.
FIG. 2A to FIG. 2E are a plan view, a side view and a cross-sectional view showing an example of a heater envelope.
FIG. 3 is a view explaining the positional relationship between the heater and a sample.
FIG. 4 is a plan view showing the holder front end portion in a state that a sample, the heater and the heater envelope are attached to a holder outer frame.
FIG. 5 is a perspective view corresponding to FIG. 4 .
FIG. 6 is a side view showing the heater envelope in which the heater is mounted with a sample.
FIG. 7 is a flow chart showing the procedure of a method of observing a sample using the sample heating holder in accordance with the present invention.
FIG. 8 is a schematic view showing an incident direction a of an electron beam to a sample at observation and an incident direction b of an FIB to a sample at milling.
FIG. 9 is a schematic cross-sectional view showing a sample holder of a heating furnace type.
FIG. 10 is a graph showing comparison between the required time reaching a target temperature of the sample heating holder in accordance with the present invention and that of a conventional sample heating holder.
FIG. 11 is a graph showing comparison between the change of sample drift over time by the sample heating holder in accordance with the present invention and that by the conventional sample heating holder.
FIG. 12 A and FIG. 12B are microscopic photographs showing examples of a TEM image of a thin film portion of a sample obtained using the sample heating holder and a TEM image obtained by milling a bulk portion of the sample after heating.
FIG. 13 is a view showing an example of an FIB milling apparatus to which the sample heating holder in accordance with the present invention is applied.
FIG. 14A to FIG. 14C are views showing other charged particle beam apparatuses to which the sample heating holder in accordance with the present invention is applied.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the present invention will be described below, referring to the accompanied drawings. FIG. 1 is an exploded perspective view showing an example of an front end portion of a sample heating holder for electron microscope in accordance with the present invention. FIG. 2A to FIG. 2E are a plan view, a side view and a cross-sectional view showing an example of a heater envelope. FIG. 3 is a view explaining the positional relationship between the heater and a sample. FIG. 4 is a plan view showing the holder front end portion in a state that a sample, the heater and the heater envelope are attached to a holder outer frame. FIG. 5 is a perspective view corresponding to FIG. 4 .
The front end portion of the holder is composed of a heater envelope 1 , a heater 2 and a holder outer frame 3 . The heater envelope 1 shown here as an example is formed in a bottomless box-shape having a brim-shaped portion 16 projecting inside from a lower end of a side surface in the bottom portion. However, the heater envelope may have a bottom or no bottom at all. On a top surface of the heater envelope 1 , there is formed a hole 11 which an electron beam or an X-ray for observing and analyzing a sample passes through. a receiving portion 13 for a retaining spring 4 provided in the holder outer frame 3 is formed in one side portion of the heater envelope 1 , and a receiving portion 14 for a rod 7 is formed in the other side portion in the opposite side. A hole 15 for leading out a lead wire of the heater 2 outside the heater envelope 1 is formed beside the rod receiving portion 14 . Depressed portions 12 a , 12 b for receiving ends of pivot screws 5 a , 5 b are formed on the other two side surfaces of the heater envelope 1 . An opening 17 for letting in an ion beam for re-milling a sample is formed beside one of the depressed portions 12 a.
The heater 2 is formed in a double stage coil shape and contained inside the heater envelope 1 , and only the lead wire is extracted outside through the hole 15 in the heater envelope 1 . The heater 2 is adhered and fixed to an inner portion of the heater envelope 1 using a high temperature thermosetting liquid inorganic heat resistant adhesive, for example, “SUMICERAM” (a trade name of a product of Asahi Chemical Industry, Co.). The sample 8 is placed between the two stages of the heater 2 , and adhered and fixed to the heater 2 using a high temperature thermosetting liquid inorganic heat resistant adhesive, for example, “SUMICERAM” (a trade name of a product of Asahi Chemical Industry, Co.). The heater 2 having the sample 8 fixed between the two stages is set into the holder outer frame 3 together with the heater envelope 1 using the pivot screws 5 a , 5 b.
The retaining spring 4 for fixing the heater envelope, the pivot screws 5 a , 5 b , a screw 6 b for fixing the lead wire of the heater 2 , a slot 20 capable of letting in an FIB for re-milling the sample are provided in the holder outer frame 3 . The slot 20 is formed at a position overlapping with an opening 17 provided in the side portion of the heater envelope 1 . Further, extended in the axial direction of the sample holder is a rod 7 for fixing the heater envelope 1 and electrocally connecting the same with the rod 7 so as to permit the bi-axial or double tilting of the heater envelope 1 . The rod 7 is movable in a direction of connecting between the pivot screws 5 a , 5 b (a direction shown by an arrow 21 of FIG. 4) by a driving means, not shown.
As shown in the side view of FIG. 2A, the heater envelope 1 is opened at a position of the retaining spring 4 provided in the one side portion, and the opening 18 is used as an inserting entrance for inserting a sample. Further, as shown in the side view of FIG. 2C, the bottom surface of the rod receiving portion 14 is inclined, and the end portion of the rod 7 contacts with the inclined surface. Therein, FIG. 2D is a cross-sectional view being taken on the plane of the line A—A of FIG. 2 B.
As shown in the plan view of FIG. 4, the heater envelope 1 is rotatably supported by the screws 5 a , 5 b , and forced to be rotated by the retaining spring 4 so as to move downward in the one side portion. However, the movement is blocked by the rod 7 contacting with the rod receiving portion 14 provided in the other side portion. A rotating angle of the heater envelope 1 around the pivot screws 5 a , 5 b is determined by a position on the inclining surface of the rod receiving portion 14 which the rod 7 is brought in contact with. That is, the angle can be adjusted by changing a position of the rod 7 in the direction connecting the pivot screws 5 a , 5 b (the direction shown by an arrow 21 of FIG. 4 ). Further, the holder main body is rotatable around the axis, as shown by an arrow 19 of FIG. 4 . Therefore, the sample heating holder in accordance with the present invention has a bi-axial or double tilting function by rotation around the axis of the holder main body and rotation around the pivot screws 5 a , 5 b of the heater envelope 1 . One side of the lead wire of the heater extracted through the hole 15 provided in the side portion of the heater envelope 1 is fixed to the holder outer frame 3 with a screw 6 a , and the other side is fixed to the rod 7 with a screw 6 b and connected to a direct current power source 9 .
FIG. 3 is a view explaining the positional relationship between the heater 2 and the sample 8 . The heater 2 is composed of two coil-shaped stages connected to each other, and the sample 8 , a part of which is formed in a thin film by milled using an FIB milling apparatus, is arranged between the two stages. The sample 8 is directly fixed to the heater 2 using a high temperature thermosetting liquid inorganic heat resistant adhesive, for example, “SUMICERAM” (a trade name of a product of Asahi Chemical Industry, Co.). The actual gap in the heater 2 is narrower than a gap shown in FIG. 3 and is such a distance that the heater is in contact with the sample 8 . Further, since the heater 2 is fixed to the inside of the heater envelope 1 , attaching work of the sample 8 to the heater 2 is performed through the opening 18 of the heater envelope 1 . The sample 8 is placed so that the thin portion milled with the FIB faces the slot 20 in the holder outer frame 3 . FIG. 6 is a side view showing the heater envelope 1 in which the heater 2 is mounted with the sample 8 . An unmilled portion of the sample 8 can be seen through the opening 17 in the side portion of the heater envelope 1 .
FIG. 7 is a flow chart showing the procedure of a method of observing a sample using the sample heating holder in accordance with the present invention. Initially, the sample 8 milled into a thin film using the FIB milling apparatus is fixed in a gap of the heater 2 fixed to the heater envelope 1 (S 11 ). Next, the heater envelope 1 having the fixed sample 8 is fixed to the holder outer frame 3 , as shown in FIG. 4 (S 12 ). The pivots 5 a , 5 b are of a screw type, and fixing of the heater envelope 1 to the holder outer frame 3 is performed as follows. Under a state that the ends of the pivot screws are drawn back, the heater envelope 1 is inserted into the holder outer frame 3 to set the retaining spring 4 and the rod 7 to the receiving portions 13 , 14 , respectively. Then, the ends of the pivot screws 5 a , 5 b are pushed into the depressed portions 12 a , 12 b in the side portion of the heater envelope 1 to finally fix the heater envelope 1 to the holder outer frame 3 .
Next, the holder is inserted into a TEM and connected to the heating power source 9 (S 13 ). After that, transmission electron microscopic observation and EDX analysis are performed while the sample is being heated by conducting current to the heater 2 (S 14 ). FIG. 8 is a schematic view showing an incident direction a of an electron beam to the sample 8 at observation and an incident direction b of an FIB to the sample 8 at milling in Step 18 to be described later. At TEM observation in Step 14 , the electron beam is launched in the direction a in the TEM, and the transmitted electron beam is image formed, and the transmitted image is observed. Change of the sample 8 caused by heating can be observed by conducting current to the heater 2 . Therein, the sample 8 is heated up to a high temperature in a short time since the sample 8 is heated from the both surface sides and heat dissipation is prevented by the heater envelope 1 made of a ceramic, and the heater 2 is fixed to the heater envelope 1 and the sample 8 is also fixed to the heater 2 . Thus, thermal drift caused by temperature rise can be suppressed, and accordingly high temperature and atomic level observation can be performed. The sample 8 is tilted by rotating the holder shaft or by changing the position of the rod 7 to the heater envelope 1 , if necessary.
After finishing observation of the sample under a heating condition, the heating is stopped (S 15 ), and the sample 8 together with the holder is extracted from the TEM (S 16 ) and inserted into the FIB apparatus (S 17 ). In the FIB apparatus, the holder is set in such a direction that the focused ion beam is incident to the sample 8 from the direction of the arrow b shown in FIG. 8 to the sample 8 and through the slot 20 of the holder outer frame 3 and the opening 17 of the heater envelope 1 . An un-milled bulk portion of the sample can be seen through the slot 20 , and the position is sputtered with the FIB to obtain a new observation field (S 18 ).
After finishing the FIB milling, the holder is extracted from the FIB milling apparatus (S 19 ), and the sample 8 milled in the bulk portion is again inserted together with the holder (S 20 ), and observation and analysis are performed (S 21 ). By re-milling the un-milled portion of the sample 8 after heating according to the above-mentioned procedure, change in the bulk portion and change in the thin film portion caused by heating can be compared (S 22 ).
Required time reaching a target temperature and change of sample drift over time were compared between the sample heating holder in accordance with the present invention and a conventional sample holder of heating furnace type. A sample to be used in the sample heating holder in accordance with the present invention was prepared by cutting an Si wafer of approximately 0.3 to 0.4 mm thickness to form an Si chip of 3 mm×2 mm×0.4 mm and thinning a part of the cut chip to approximately 0.1 μm thickness by FIB milling. The prepared sample was fixed to the heater in the manner as described above.
FIG. 9 is a schematic cross-sectional view showing the sample holder of heating furnace type. In the sample holder, a heating furnace 50 made of tantalum is arranged on a hole 41 provided in a holder main body 40 , and a heater 51 is arranged around the heating furnace. A sample 55 is placed in a step portion of the heating furnace 50 , and fixed by being pushed in the edge portion with a fixing screw 52 . A lead wire 53 is connected to the heater 51 . Further, a thermocouple 54 for monitoring temperature of the heating furnace is arranged. The sample 55 is prepared by milling an Si disk of 3 mm diameter and approximately 20 μm thickness to form a thin film by ion thinning. A portion of the thin film to be observed by a TEM is as extremely thin as several nm.
FIG. 10 shows comparison between the required time reaching a target temperature of the sample heating holder in accordance with the present invention and that of a conventional sample heating holder when the target temperature is set to 1000° C . The conventional sample holder required 20 minutes to reach the target temperature because of indirect heating which took a long time to transfer heat from the heater to the sample. On the other hand, the sample holder in accordance with the present invention could reach the target temperature in approximately 5 minutes.
FIG. 11 shows comparison between the change of sample drift over time by the sample heating holder in accordance with the present invention and that by the conventional sample heating holder. The conventional sample holder required 120 minutes until the amount of drift per second was stabilized to 0.2 nm because of indirect heating which took a long time to stabilize the whole sample holder. On the other hand, in the sample holder in accordance with the present invention, the amount of drift was stabilized to the value 0.2 nm per second in approximately 20 minutes because the sample holder was of direct heating type by the heater, and the heater was fixed to the heater envelope, and the sample was also fixed to the heater.
FIG. 12 A and FIG. 12B are microscopic photographs showing examples of a TEM image of a thin film portion of a sample obtained using the sample heating holder and a TEM image obtained by milling a bulk portion of the sample after heating. FIG. 12A is a crystal lattice image of SiC heated up to approximately 1500° C. after being formed in a thin film by FIB milling. FIG. 12B is a crystal lattice image of SiC which was observed by again milling the bulk portion with FIB after observing the TEM image of FIG. 12 A. In this example, both of the crystal lattice image of the bulk portion and the crystal lattice image of the thin film portion show a similar polymorphic structure. Therefore, in the comparison in Step 22 of FIG. 7, the change occurred in the thin film portion of the sample during the heating process, that is, the change observed by the TEM can be estimated to be the same as the change occurred in the bulk portion.
FIG. 13 is a view showing an example of an FIB milling apparatus to which the sample heating holder in accordance with the present invention is applied. The reference character 61 indicates an ion source, and an ion beam emitted from the ion source is irradiated onto a sample through a condenser lens 62 , an aperture 63 , a scanning deflector 64 and an objective lens 65 . The sample is placed on a side-entry stage 66 including the sample heating holder in accordance with the present invention, and the side-entry stage 66 is inserted into a sample fine motion mechanism 67 . Therefore, the sample can be freely moved to the irradiation position of the ion beam.
A secondary charged particle detector 68 is for detecting a secondary signal (secondary electrons, secondary ions or the like) produced from the sample by the ion beam, and the detected signal becomes a brightness signal of a CRT (not shown).
Further, a vacuum seal member is put between the side-entry stage 66 and the sample fine motion mechanism 67 so that a vacuum inside a sample chamber 69 can be maintained under a condition that the side-entry stage 66 is inserted into the sample fine motion mechanism 67 .
FIG. 14A to FIG. 14C are views showing apparatuses for further milling or observing an FIB milled sample. FIG. 14A is an argon milling apparatus, FIG. 14B is a scanning electron microscope (SEM) and FIG. 14C is a TEM described above. A point common to these apparatuses is that each of the apparatuses comprises a sample fine motion mechanism 67 having the same designed inserting port. Therefore, it is possible, for example, that a surface milled by FIB is etched to form an observation surface using the argon milling apparatus and observed with the SEM, and a result of the observation shows that a slightly deeper cross section of the observation portion should be observed, and the sample is again milled by FIB and finally observed using the TEM.
It is also possible that the portion of the sample heating holder in accordance with the present invention is designed so as to be detachable, and the holder portion is attached to the side-entry stage at TEM observation, and the portion is detached and attached to a stage provided in a sample chamber of the FIB milling apparatus at FIB milling.
As having been described above, according to the present invention, high resolution observation of a sample under high temperature using an electron microscope can be performed irrespective of shape of the sample and irrespective of direction of the sample to an electron beam, with suppressing drift caused by heat and with a high thermal efficiency. Further, re-milling of the sample using a focused ion beam milling apparatus and re-observation of the sample using electron microscope can be performed after observing the sample under a heating condition, and accordingly, observation of an inner bulk portion of the sample under a heating condition and verification by comparing it with a thin film portion can be performed.
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High resolution observation of a sample at a high temperature above 1000° C. is accomplished by suppressing sample drift by heating over a short time and with small electric current. A heater envelope made of a ceramic having a carbon coating on the surface is attached around a heater surrounding the sample. The heater envelope is rotatable around pivot screws, and has an outer frame portion of a holder individually having slots capable of letting an FIB enter so that the sample mounting on the holder, as it is, may be milled with the FIB.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a shielding system for a printed circuit board, and in particular, to a shielding system having an integral shielding enclosure with a fixed cover that may be permanently removed, and a replacement cover for attaching thereto.
2. Description of the Related Art
As is well known in the prior art, selected electric or electronic parts on a printed circuit board radiate electromagnetic waves which thereby cause noise or unwanted signals to appear in adjacent components on the printed circuit board or electric or electronic parts and devices existing in the vicinity of the printed circuit board. Accordingly, it is highly desirable to provide shielding for electronic components of printed circuit boards such as those found in radio transmitters, radio receivers, computers and other electronic devices that use circuitry that emits or is susceptible to electromagnetic radiation. It is known that these components can be shielded to reduce undesirable electromagnetic interference and/or susceptibility effects with the use of a conductive shield that reflects or dissipates the electromagnetic charges and fields. Such shielding may be grounded to allow the offending electrical charges and fields to be dissipated without disrupting the operation of the electronic components enclosed within the shield.
A variety of devices have been utilized for shielding electronic components, but these prior art devices have not been entirely satisfactory since they do not allow for easy access to the underlying electronic component after the installation of the shield.
For example, a conventional metal shield cover, or can, is mounted to a printed circuit board by using fasteners appropriate for the purpose. Thereafter, the metal shield is soldered or welded to selected grounding strips on the printed circuit board at selected locations of its side walls. Using solder or welding to mechanically hold and electrically connect the metal shield to the printed circuit board permanently affixes the metal shield over the selected electronic component(s).
After assembling the completed printed circuit board, including the required metal shields, the printed circuit board will generally be subjected to a "burn-in" stage during which it is subjected to elevated temperature tests. If one of the electronic components should fail during the burn-in, however, that component must be replaced. Thus, it becomes necessary to desolder or unweld the metal shield from the printed circuit board in order to obtain access to the failed component and replace the same. This is very difficult to successfully accomplish and, more than likely, the entire printed circuit board will be destroyed.
In order to overcome this problem, shielding devices, such as that disclosed in U.S. Pat. No. 4,754,101 of the present assignee, the entire contents of which are hereby incorporated by reference, have included a separate wall enclosure and a removable cover. The cover is resiliently held in place by deflectable engagement prongs extending from an upper edge of the wall enclosure. The presence of the resiliently held cover allows access to the underlying electronic component, should the same be required, however, the manufacturing costs associated with the formation of the engagement prongs are also increased.
Accordingly, there exists a need for a shielding cover which can be soldered to the printer circuit board, but which still allows access to the underlying electronic component should it be necessary to replace, repair or otherwise adjust the same, and which can be inexpensively manufactured.
SUMMARY OF THE INVENTION
The present invention overcomes these disadvantages by providing an electromagnetic shielding system including a shielding enclosure having a plurality of side walls and an integral top surface. The top surface includes a scored line for allowing removal of an interior portion of the top surface to thereby define a remaining perimeter rim. A replacement cover is also included for attachment to the remaining cover rim after the interior portion is removed. The replacement cover may include a metal foil having an adhesive surface or a metal sheet material.
The present invention further provides a method for shielding and obtaining access to a component on a printed circuit board. The method includes providing a printed circuit board having a component encompassed by a shielding enclosure. The shielding enclosure includes a plurality of side walls and an integral top surface having a scored line which defines an interior portion. The scored line on the top surface of the shielding enclosure is severed and the interior portion of the top surface defined by the scored line is removed to thereby leave a remaining perimeter rim on the printed circuit board and allow access to the component within the rim. The scored line may be severed by grasping a hole in the top surface of the shielding enclosure and applying force. A replacement cover is also provided for the top surface of the shielding enclosure. The replacement cover is attached to the shielding enclosure to thereby encompass and shield the component.
BRIEF DESCRIPTION OF THE DRAWINGS
These, and other, objects, features and advantages of the present invention will become more readily apparent to those skilled in the art upon reading the following detailed description, in conjunction with the appended drawings, in which:
FIG. 1 is a perspective view of a printed circuit board shielding enclosure in accordance with the present invention;
FIG. 2 is a replacement cover for the enclosure shown in FIG. 1, in accordance with a first embodiment of the present invention;
FIG. 3 is a replacement cover for the enclosure shown in FIG. 1, in accordance with a second embodiment of the present invention;
FIG. 4 is a perspective view of the shielding enclosure of FIG. 1 with the cover having been removed; and
FIG. 5 is a perspective view of the shielding enclosure of FIG. 4 with the replacement cover of FIG. 3 attached thereto.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, an electromagnetic shielding system for a printed circuit board in accordance with the present invention is shown generally by reference numeral 10. Shielding system 10 is designed to be welded, soldered, or otherwise fixed to a printed circuit board (not shown) during the manufacture thereof and thereby encompass and shield one or more underlying electronic components that are mounted on the printed circuit board. The electromagnetic shielding system 10 can be used to shield either a section or component of a printed circuit board or the entire board.
Shielding system 10 includes an enclosure 12 defined by side walls 14 and a top surface 16 integrally joined therewith. If desired, the walls 14 could be formed into any reasonable configuration. However, in the preferred embodiment, the walls 14 are formed into a square, rectangle or other quadrilateral shape. By using the walls 14 in the form of a rectangle, the configuration of the top surface 16 is simplified along with a simplification of mounting the walls 14 on a conventional printed circuit board. The walls 14 and the top surface 16 are preferably made from a metallic material, such as tin plated steel. However, other materials including other metals such as tin plated phosphor bronze, beryllium copper and other alloys of copper may of course also be used depending upon the required shielding. In particular, however, it is desirable that the material be metals that are capable of being readily soldered or welded and capable of low resistance electrical conductivity. However, if the primary purpose of the shield is to reduce magnetic field interference, it is generally preferable to use a steel or other alloy which has a relatively high permeability at low frequencies. To provide electrical conductivity on materials with relatively high resistance, the material may be plated with a low resistance metal, such as tin. If the principal concern is to reduce electrical field interference, then it is generally preferable to use a copper alloy as will be readily apparent to one skilled in the art of electromagnetic shielding. The walls 14 and the top surface 16 preferably have a thickness of approximately 0.005 in. when the metal material is tin plated steel, tin plated phosphor bronze, or stainless steel. Other thicknesses could of course also be used depending upon the material used to form the walls 14 and the top surface 16 and the end use environment in which the enclosure 12 will be placed.
Each of the walls 14 includes a side member portion 18 and, preferably, one or more projections 20 extending from a lower edge of the side member portion 18. The projections 20 are preferably soldered to the printed circuit board to obtain a surface mount thereon, although through hole mounting or any other type of known mounting arrangement could also be utilized. In this regard, the enclosures 12 of the present invention are adaptable for tape and reel packaging for use in standard automated pick and place equipment or, alternatively, the enclosures of the present invention may be packed in trays for correct orientation within an automated system or, still further, they be may packed in bulk as may be required by conventional equipment.
As shown in FIG. 1, the top surface 16 includes a scored line 22 extending parallel to the perimeter thereof. Although illustrated as being scored substantially continuously around the perimeter, it is also within the scope of the present invention that the scored line 22 may not be continuous and that it may include portions therealong that are not scored, such as along one or more sides of the top surface for example. A non-continuous scored line 22 may be used in order to increase the rigidity of the top surface 16 and its ability to withstand vibrations and shocks encountered during use. The scored line 22 is preferably spaced approximately 0.020 in. from the outer perimeter edge in the illustrated embodiment, however, it will be apparent to one skilled in the art that other placements could of course also be used depending upon the specific configuration and size of the enclosure and the top surface thereof. The scored line 22 allows an interior portion 26 of the top surface 16 to be removed, and thereby define a remaining perimeter rim 28, as shown in FIG. 4. Being able to remove an integral portion of the top surface, i.e., the interior portion 26, allows access to be gained to an underlying electronic component without removing the entire enclosure 12, as discussed in further detail below.
If desired for ventilation, the top surface 16 may include air vents 24 in the form of small circular holes as shown in FIG. 1. The vents 24 illustrated in the corners of the top surface assist, in conjunction with the score line 22, in allowing for the break away of the interior portion. The vents or holes 24 disposed in the interior portion 26 can additionally serve as thumb nail grips for starting the removal of the same. The top surface 16 may include, instead of or in addition to the vents 24, louvers or perforations for ventilation, heat sink components, handles, or other hardware to suit a specific need or function. In addition, material to absorb electrical energy, such as a microwave absorber, may be attached or bonded to the inside of the top surface 16.
If it is necessary to access an electronic component shielded by the enclosure 12, and the interior portion 26 of the top surface 16 is removed, it is also then necessary to provide a cover which will replace the removed interior portion 26 after the repair or replacement of the electronic component is performed. Referring to FIG. 2, a replacement cover 30 is shown in accordance with the present invention. The replacement cover 30 is preferably made from the same metal material as the enclosure 12, although a different metal material could of course also be used. The replacement cover 30 also includes vents 24 and a plurality of etched formed or lanced elements 32 which are provided in order to assist in self locating the cover 30 on top of the perimeter rim. Replacement cover 30 is attached to the perimeter rim 28 of the enclosure 12 by welding, soldering, or any other conventional attachment means.
Alternatively, a further embodiment of the replacement cover is shown in FIG. 3 by reference numeral 30'. Replacement cover 30' includes a main portion 38 generally corresponding in shape to the configuration of the perimeter rim 28. Preferably, cover 30' also includes a plurality of side flanges 40 extending therefrom and a plurality of predefined bend lines 42 disposed between the main portion 38 and the flanges 40. Replacement cover 30' is made from a metal foil and includes an adhesive surface 34 that is, at least initially, provided with a release paper 36. Replacement cover 30' is attached to the perimeter rim 28 of the enclosure, and also preferably the side walls 14, by removing the release paper 36 to expose the adhesive surface 34, and by bringing the adhesive surface 34 into contact with the rim 28 and folding down the side flanges 40 along the bend lines 42 to thereby bring the flanges 40 into contact with the side walls 14, as shown in FIG. 5.
The operation of the shielding system 10 of the present invention can be described as follows. During the initial manufacture of a printed circuit board, shielding enclosure 12 is disposed over one or more electric or electronic components or the entire board, in order to reduce the electromagnetic interference with adjacent components. At some point in time after burn-in, or later, it may become necessary to replace, repair or otherwise adjust one of the components being shielded by the enclosure 12. In such instance, the score line 22 allows the interior portion 26 of the enclosure 12 to be removed using the vents 24 as grips or otherwise exerting a slight force to sever the score line 22 and completely separate the interior portion 26. As shown in FIG. 4, the perimeter rim 28 of the enclosure 12 will remain attached to the printed circuit board (not shown). Thus, the shielding system 10 of the present invention allows access to the failed component such that the component itself may be replaced, rather than declaring the entire printed circuit board an entire loss.
After the failed or damaged component is removed from within the rim 28 on the printed circuit board and a new or repaired component is inserted, or after the failed or damaged component is repaired or otherwise adjusted while still on the printed circuit board, the replacement cover 30, 30' is then attached to the perimeter rim 28 in order to again form a complete shielding enclosure over the electronic component. As shown in FIG. 5, the replacement cover 30' is attached to the perimeter 28 by applying the adhesive surface 34 directly thereto. Similarly, replacement cover 30 is welded, soldered, or otherwise mechanically attached to the perimeter 28. In each instance, the replacement cover 30, 30' together with the perimeter rim 28 encompass and shield the one or more underlying electronic components that are mounted on the printed circuit board.
The shielding system 10 of the present invention may be easily and inexpensively manufactured, in comparison with the resiliently held covers of the prior art. During manufacture, the enclosure 12 including the cover 16 is stamped or punched from a sheet material. The score line 22 and air vents 24 are also cut into the sheet material at this stage. Afterwards, the sides of the enclosure are bent to form the side member portions 18 and thereby obtain the final product. The covers 30, 30' are likewise easily formed using standard sheet metal or sheet foil processing techniques.
While the present invention has been described with preferred embodiments, it is to be understood that variations and modifications may be resorted to as will be apparent to those skilled in the art. Such variations and modifications are to be considered within the purview and the scope of the claims appended hereto.
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A method for shielding and obtaining access to a component on a printed circuit board including providing a printed circuit board having a component encompassed by a shielding enclosure including a plurality of side walls and an integral top surface having a scored line which defines an interior portion, severing the scored line, removing the interior portion leaving the shielding enclosure with a remaining perimeter rim and allowing access to the component, providing a replacement cover for the shielding enclosure, and attaching the replacement cover to the shielding enclosure to replace the interior portion and to thereby encompass and shield the component. The replacement cover may be attached by soldering or by an adhesive surface of the replacement cover.
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[0001] This application is a continuation of copending application Ser. No. 10/413,076, filed on Apr. 14, 2003, which is a continuation of application Ser. No. 10/151,833, filed on May 21, 2002, now abandoned, which is a divisional of application Ser. No. 09/884,412, filed on Jun. 19, 2001, now U.S. Pat. No. 6,419,958, which is a divisional of application Ser. No. 09/488,629, filed on Jan. 20, 2000, now U.S. Pat. No. 6,274,171, which is a continuation-in-part of application Ser. No. 08/964,328, filed on Nov. 5, 1997, now abandoned, which is a continuation-in-part of application Ser. No. 08/821,137, filed on Mar. 20, 1997, now abandoned, which claims priority from Provisional Application No. 60/014,006, filed on Mar. 25, 1996, the entire disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] Extended release drug formulations are conventionally produced as compressed tablets by hydrogel tablet technology. To produce these sustained release tablet drug dosage forms, the active ingredient is conventionally compounded with cellulose ethers such as methyl cellulose, ethyl cellulose or hydroxypropylmethylcellulose with or without other excipients and the resulting mixture is pressed into tablets. When the tablets are orally administered, the cellulose ethers in the tablets swell upon hydration from moisture in the digestive system, thereby limiting exposure of the active ingredient to moisture. As the cellulose ethers are gradually leached away by moisture, water more deeply penetrates the gel matrix and the active ingredient slowly dissolves and diffuses through the gel, making it available for absorption by the body. An example of such a sustained release dosage form of the analgesic/anti-inflammatory drug etodolac (Lodine®) appears in U.S. Pat. No. 4,966,768. U.S. Pat. No. 4,389,393 discloses sustained release therapeutic compressed solid unit dose forms of an active ingredient plus a carrier base comprised of a high molecular weight hydroxypropylmethylcellulose, methyl cellulose, sodium carboxymethylcellulose and or other cellulose ether.
[0003] Where the production of tablets is not feasible, it is conventional in the drug industry to prepare encapsulated drug formulations which provide extended or sustained release properties. In this situation, the extended release capsule dosage forms may be formulated by mixing the drug with one or more binding agents to form a uniform mixture which is then moistened with water or a solvent such as ethanol to form an extrudable plastic mass from which small diameter, typically 1 mm, cylinders of drug/matrix are extruded, broken into appropriate lengths and transformed into spheroids using standard spheronization equipment. The spheroids, after drying, may then be film-coated to retard dissolution. The film-coated spheroids may then be placed in pharmaceutically acceptable capsules, such as starch or gelatin capsules, in the quantity needed to obtain the desired therapeutic effect. Spheroids releasing the drug at different rates may be combined in a capsule to obtain desired release rates and blood levels. U.S. Pat. No. 4,138,475 discloses a sustained release pharmaceutical composition consisting of a hard gelatin capsule filled with film-coated spheroids comprised of propanolol in admixture with microcrystalline cellulose wherein the film coating is composed of ethyl cellulose, optionally, with hydroxypropylmethylcellulose and/or a plasticizer.
[0004] Venlafaxine, 1-[2-(dimethylamino)-1-(4-methoxyphenyl)ethyl]cyclohexanol, is an important drug in the neuropharmacological arsenal used for treatment of depression. Venlafaxine and the acid addition salts thereof are disclosed in U.S. Pat. No. 4,535,186. Venlafaxine hydrochloride is presently administered to adults in compressed tablet form in doses ranging from 75 to 350 mg/day, in divided doses two or three times a day. In therapeutic dosing with venlafaxine hydrochloride tablets, rapid dissolution results in a rapid increase in blood plasma levels of the active compound shortly after administration followed by a decrease in blood plasma levels over several hours as the active compound is eliminated or metabolized, until sub-therapeutic plasma levels are approached after about twelve hours following administration, thus requiring additional dosing with the drug. With the plural daily dosing regimen, the most common side effect is nausea, experienced by about forty five percent of patients under treatment with venlafaxine hydrochloride. Vomiting also occurs in about seventeen percent of the patients.
BRIEF DESCRIPTION OF THE INVENTION
[0005] In accordance with this invention, there is provided an extended release (ER), encapsulated formulation containing venlafaxine hydrochloride as the active drug component, which provides in a single dose, a therapeutic blood serum level over a twenty four hour period.
[0006] Through administration of the venlafaxine formulation of this invention, there is provided a method for obtaining a flattened drug plasma concentration to time profile, thereby affording a tighter plasma therapeutic range control than can be obtained with multiple daily dosing. In other words, this invention provides a method for eliminating the sharp peaks and troughs (hills and valleys) in blood plasma drug levels induced by multiple daily dosing with conventional immediate release venlafaxine hydrochloride tablets. In essence, the plasma levels of venlafaxine hydrochloride rise, after administration of the extended release formulations of this invention, for between about five to about eight hours (optimally about six hours) and then begin to fall through a protracted, substantially linear decrease from the peak plasma level for the remainder of the twenty four hour period, maintaining at least a threshold therapeutic level of the drug during the entire twenty-four period. In contrast, the conventional immediate release venlafaxine hydrochloride tablets give peak blood plasma levels in 2 to 4 hours. Hence, in accordance with the use aspect of this invention, there is provided a method for moderating the plural blood plasma peaks and valleys attending the pharmacokinetic utilization of multiple daily tablet dosing with venlafaxine hydrochloride which comprises administering to a patient in need of treatment with venlafaxine hydrochloride, a one-a-day, extended release formulation of venlafaxine hydrochloride.
[0007] The use of the one-a-day venlafaxine hydrochloride formulations of this invention reduces by adaptation, the level of nausea and incidence of emesis that attend the administration of multiple daily dosing. In clinical trials of venlafaxine hydrochloride ER, the probability of developing nausea in the course of the trials was greatly reduced after the first week. Venlafaxine ER showed a statistically significant improvement over conventional venlafaxine hydrochloride tablets in two eight-week and one 12 week clinical studies. Thus, in accordance with this use aspect of the invention there is provided a method for reducing the level of nausea and incidence of emesis attending the administration of venlafaxine hydrochloride which comprises dosing a patient in need of treatment with venlafaxine hydrochloride with an extended release formulation of venlafaxine hydrochloride once a day in a therapeutically effective amount.
[0008] The formulations of this invention comprise an extended release formulation of venlafaxine hydrochloride comprising a therapeutically effective amount of venlafaxine hydrochloride in spheroids comprised of venlafaxine hydrochloride, microcrystalline cellulose and, optionally, hydroxypropylmethylcellulose coated with a mixture of ethyl cellulose and hydroxypropylmethylcellulose. Unless otherwise noted, the percentage compositions mentioned herein refer to percentages of the total weight of the final composition or formulation.
[0009] More particularly, the extended release formulations of this invention are those above wherein the spheroids are comprised of from about 6% to about 40% venlafaxine hydrochloride by weight, about 50% to about 95% microcrystalline cellulose, NF, by weight, and, optionally, from about 0.25% to about 1% by weight of hydroxypropylmethylcellulose, USP, and coated with from about 2% to about 12% of total weight of film coating comprised of from about 80% to about 90% by weight of film coating of ethyl cellulose, NF, and from about 10% to about 20% by weight of film coating of hydroxypropylmethylcellulose, USP.
[0010] A preferred embodiment of this invention are formulations wherein the spheroids are comprised of about 30% to about 40% venlafaxine hydrochloride by weight, about 50% to about 70% microcrystalline cellulose, NF, by weight, and, optionally, from about 0.25% to about 1% by weight of hydroxypropylmethylcellulose, USP, and coated with from about 2% to about 12% of total weight of film coating comprised of from about 80% to about 90% by weight of film coating of ethyl cellulose, NF, and from about 10% to about 20% by weight of film coating of hydroxypropylmethylcellulose, USP.
[0011] Another preferred lower dose formulation of this invention are those wherein the spheroids are comprised less than 30% venlafaxine hydrochloride. These formulations comprise spheroids of from about 6% to about 30% venlafaxine hydrochloride by weight, about 70% to about 94% microcrystalline cellulose, NF, by weight, and, optionally, from about 0.25% to about 1% by weight of hydroxypropylmethylcellulose, USP, and coated with from about 2% to about 12% of total weight of film coating comprised of from about 80% to about 90% by weight of film coating of ethyl cellulose, NF, and from about 10% to about 20% by weight of film coating of hydroxypropylmethylcellulose, USP.
[0012] Within this subgroup of lower dose formulations are formulations in which the spheroids are comprised of from about 6% to about 25% venlafaxine hydrochloride and from about 94% to about 75% microcrystalline cellulose, with an optional amount of from 0.25% to about 1% by weight of hydroxypropylmethylcellulose. Another preferred subgroup of spheroids in these formulations comprises from about 6% to about 25% venlafaxine hydrochloride and from about 94% to about 75% microcrystalline cellulose, with an optional amount of from 0.25% to about 1% by weight of hydroxypropylmethylcellulose. A further preferred subgroup of spheroids in these formulations comprises from about 6% to about 20% venlafaxine hydrochloride and from about 94% to about 80% microcrystalline cellulose, with an optional amount of from 0.25% to about 1% by weight of hydroxypropylmethylcellulose. Within each of these subgroups is understood to be formulations in which the spheroids are comprised of venlafaxine HCl and microcrystalline cellulose in the amounts indicated, with no hydroxypropylmethylcellulose present. Each of these formulations is also preferably contained in a gelatin capsule, preferably a hard gelatin capsule.
DETAILED DESCRIPTION OF THE INVENTION
[0013] 1-[2-(dimethylamino)-1-(4-methoxyphenyl)ethyl]cyclohexanol hydrochloride is polymorphic. Of the forms isolated and characterized to date, Form I is considered to be the kinetic product of crystallization which can be converted to Form II upon heating in the crystallization solvent. Forms I and II cannot be distinguished by their melting points but do exhibit some differences in their infrared spectra and X-ray diffraction patterns. Any of the polymorphic forms such as Form I or Form II may be used in the formulations of the present invention.
[0014] The extended release formulations of this invention are comprised of 1-[2-(dimethylamino)-1-(4-methoxyphenyl)ethyl] cyclohexanol hydrochloride in admixture with microcrystalline cellulose and hydroxypropylmethylcellulose. Formed as beads or spheroids, the drug containing formulation is coated with a mixture of ethyl cellulose and hydroxypropylmethyl cellulose to provide the desired level of coating, generally from about two to about twelve percent on a weight/weight basis of final product or more preferably from about five to about ten percent (w/w), with best results obtained at from about 6 to about 8 percent (w/w). More specifically, the extended release spheroid formulations of this invention comprise from about 30 to 40 percent venlafaxine hydrochloride, from about 50 to about 70 percent microcrystalline cellulose, NF, from about 0.25 to about 1 percent hydroxypropylmethylcellulose, USP, and from about 5 to about 10 percent film coating, all on a weight/weight basis. And preferably, the spheroid formulations contain about 35 percent venlafaxine hydrochloride, about 55 to 60 percent microcrystalline cellulose NF (Avicel® PH101), about one half percent hydroxypropylmethylcellulose 2208 USP (K3, Dow, which has a viscosity of 3 cps for 2% aqueous solutions, a methoxy content of 19-24% and a hydroxypropoxy content of 4-13%), and from about 6 to 8 percent film coating.
[0015] The film coating is comprised of 80 to 90 percent of ethyl cellulose, NF and 10 to 20 percent hydroxypropylmethylcellulose (2910), USP on a weight/weight basis. Preferably the ethyl cellulose has a ethoxy content of 44.0-51% and a viscosity of 50 cps for a 5% aqueous solution and the hydroxypropylmethylcellulose is USP 2910 having a viscosity of 6 cps at 2% aqueous solution with a methoxy content of 28-30% and a hydroxypropoxy content of 7-12%. The ethyl cellulose used herein is Aqualon HG 2834.
[0016] Other equivalents of the hydroxypropylmethylcelluloses 2208 and 2910 USP and ethyl cellulose, NF, having the same chemical and physical characteristics as the proprietary products named above may be substituted in the formulation without changing the inventive concept. Important characteristics of suitable hydroxypropylmethylcelluloses include a low viscosity, preferably less than 10 cps and more preferably 2-5 cps, and a gel temperature above that of the temperature of the extrudate during extrusion. As explained below, these and other characteristics which enable the extrudate to remain moist and soft (pliable) are preferred for the hydroxypropylmethylcellulose. In the examples below, the extrudate temperature was generally 50-55° C.
[0017] It was completely unexpected that an extended release formulation containing venlafaxine hydrochloride could be obtained because the hydrochloride of venlafaxine proved to be extremely water soluble. Numerous attempts to produce extended release tablets by hydrogel technology proved to be fruitless because the compressed tablets were either physically unstable (poor compressibility or capping problems) or dissolved too rapidly in dissolution studies. Typically, the tablets prepared as hydrogel sustained release formulations gave 40-50% dissolution at 2 hrs, 60-70% dissolution at 4 hrs and 85-100% dissolution at 8 hrs.
[0018] Numerous spheroid formulations were prepared using different grades of microcrystalline cellulose and hydroxypropylmethylcellulose, different ratios of venlafaxine hydrochloride and filler, different binders such as polyvinylpyrrolidone, methylcellulose, water, and polyethylene glycol of different molecular weight ranges in order to find a formulation which would provide a suitable granulation mix which could be extruded properly. In the extrusion process, heat buildup occurred which dried out the extrudate so much that it was difficult to convert the extruded cylinders into spheroids. Addition of hydroxypropylmethylcellulose 2208 to the venlafaxine hydrochloride-microcrystalline cellulose mix made production of spheroids practical.
[0019] The encapsulated formulations of this invention may be produced in a uniform dosage for a specified dissolution profile upon oral administration by techniques understood in the art. For instance, the spheroid components may be blended for uniformity with a desired concentration of active ingredient, then spheronized and dried. The resulting spheroids can then be sifted through a mesh of appropriate pore size to obtain a spheroid batch of uniform and prescribed size.
[0020] The resulting spheroids can be coated and resifted to remove any agglomerates produced in the coating steps. During the coating process samples of the coated spheroids may be tested for their distribution profile. If the dissolution occurs too rapidly, additional coating may be applied until the spheroids present a desired dissolution rate.
[0021] The following examples are presented to illustrate applicant's solution to the problem of preparation of the extended release drug containing formulations of this invention.
EXAMPLE NO. 1
Venlafaxine Hydrochloride Extended Release Capsules
[0022] A mixture of 44.8 parts (88.4% free base) of venlafaxine hydrochloride, 74.6 parts of the microcrystalline cellulose, NF, and 0.60 parts of hydroxypropylmethyl cellulose 2208, USP, are blended with the addition of 41.0 parts water. The plastic mass of material is extruded, spheronized and dried to provide uncoated drug containing spheroids.
[0023] Stir 38.25 parts of ethyl cellulose, NF, HG2834 and 6.75 parts of hydroxypropylmethylcellulose 2910, USP in a 1:1 v/v mixture of methylene chloride and anhydrous methanol until solution of the film coating material is complete.
[0024] To a fluidized bed of the uncoated spheroids is applied 0.667 parts of coating solution per part of uncoated spheroids to obtain extended release, film coated spheroids having a coating level of 3%.
[0025] The spheroids are sieved to retain the coated spheroids of a particle size between 0.85 mm to 1.76 mm diameter. These selected film coated spheroids are filled into pharmaceutically acceptable capsules conventionally, such as starch or gelatin capsules.
EXAMPLE NO. 2
[0026] Same as for Example 1 except that 1.11 parts of the film coating solution per part of uncoated spheroids is applied to obtain a coating level of 5%.
EXAMPLE NO. 3
[0027] Same as for Example 1 except that 1.33 parts of the film coating solution is applied to 1 part of uncoated spheroids to obtain a coating level of 6%.
EXAMPLE NO. 4
[0028] Same as for Example 1 except that 1.55 parts of the film coating solution is applied to 1 part of uncoated spheroids to obtain a coating level of 7%.
[0029] In the foregoing failed experiments and in Examples 1-4, the extrusion was carried out on an Alexanderwerk extruder. Subsequent experiments carried out on Hutt and Nica extruders surprisingly demonstrated that acceptable, and even improved, spheroids could be made without the use of an hydroxypropylmethylcellulose.
[0030] In such further experiments the applicability of the invention was extended to formulations wherein the weight percentage of venlafaxine hydrochloride is 6% to 40%, preferably 8% to 35%. Thus, the extended release spheroid formulations of this invention comprise from about 6 to about 40 percent venlafaxine hydrochloride, from about 50 to about 94 percent microcrystalline cellulose, NF, optionally, from about 0.25 to about 1 percent hydroxypropylmethylcellulose, and from about 2 to about 12 percent, preferably about 3 to 9 percent, film coating.
[0031] Spheroids of the invention were produced having 8.25% (w/w) venlafaxine hydrochloride and the remainder (91.75%, w/w) being microcrystalline cellulose, with a coating of from 3 to 5% (w/w), preferably 4%, of the total weight. The spheroids with 8.25% venlafaxine hydrochloride and 4% coating were filled into No. 2 white opaque shells with a target fill weight of 236 mg.
[0032] Further spheroids of the invention were produced having 16.5% (w/w) venlafaxine hydrochloride and the remainder (83.5%, w/w) being microcrystalline cellulose, with a coating of from 4 to 6% (w/w), preferably 5%, of the total weight. The spheroids 16.5% venlafaxine hydrochloride and 5% coating were filled into No. 2 white opaque shells with a target fill weight of 122 mg.
[0033] The test for acceptability of the coating level is determined by analysis of the dissolution rate of the finished coated spheroids prior the encapsulation. The dissolution procedure followed uses USP Apparatus 1 (basket) at 100 rpm in purified water at 37° C.
[0034] Conformance with the dissolution rate given in Table 1 provides the twenty-four hour therapeutic blood levels for the drug component of the extended release capsules of this invention in capsule form. Where a given batch of coated spheroids releases drug too slowly to comply with the desired dissolution rate study, a portion of uncoated spheroids or spheroids with a lower coating level may be added to the batch to provide, after thorough mixing, a loading dose for rapid increase of blood drug levels. A batch of coated spheroids that releases the drug too rapidly can receive additional film-coating to give the desired dissolution profile.
TABLE 1 Acceptable Coated Spheroid Dissolution Rates Time (hours) Average % Venlafaxine HCl released 2 <30 4 30-55 8 55-80 12 65-90 24 >80
[0035] Batches of the coated venlafaxine hydrochloride containing spheroids which have a dissolution rate corresponding to that of Table 1 are filled into pharmaceutically acceptable capsules in an amount needed to provide the unit dosage level desired. The standard unit dosage immediate release (IR) tablet used presently provides amounts of venlafaxine hydrochloride equivalent to 25 mg, 37.5 mg, 50 mg, 75 mg and 100 mg venlafaxine. The capsules of this invention are filled to provide an amount of venlafaxine hydrochloride equivalent to that presently used in tablet form and also up to about 150 mg venlafaxine hydrochloride.
[0036] Dissolution of the venlafaxine hydrochloride ER capsules is determined as directed in the U.S. Pharmacopoeia (USP) using apparatus 1 at 100 rpm on 0.9 L of water. A filtered sample of the dissolution medium is taken at the times specified. The absorbance of the clear solution is determined from 240 to 450 nanometers (nm) against the dissolution medium. A baseline is drawn from 450 nm through 400 nm and extended to 240 nm. The absorbance at the wavelength of maximum absorbance (about 274 nm) is determined with respect to this baseline. Six hard gelatin capsules are filled with the theoretical amount of venlafaxine hydrochloride spheroids and measured for dissolution. Standard samples consist of venlafaxine hydrochloride standard solutions plus a gelatin capsule correction solution.
[0037] The percentage of venlafaxine released is determined from the equation
% Venlafaxine hydrochloride released = ( As ) ( Wr ) ( S ) ( V1 ) ( 0.888 ) ( 100 ) ( Ar ) ( V2 ) ( C )
where As is absorbance of sample preparation, Wr is weight of reference standard, mg; S is strength of the reference standard, decimal; V1 is the volume of dissolution medium used to dissolve the dosage form, mL; 0.884 is the percent free base, Ar is the absorbance of the standard preparation, V2 is the volume of reference standard solution, mL; and C is the capsule claim in mg.
[0038] Table 2 shows the plasma level of venlafaxine versus time for one 75 mg conventional Immediate Release (IR) tablet administered every 12 hours, two 75 mg extended release (ER) capsules administered simultaneously every 24 hours, and one 150 mg extended release (ER) capsule administered once every 24 hours in human male subjects. The subjects were already receiving venlafaxine hydrochloride according to the dosage protocol, thus the plasma blood level at zero time when dosages were administered is not zero.
TABLE 2 Plasma venlafaxine level (ng/mL) versus time, conventional tablet (not extended release) versus ER capsule 75 mg 1 × 150 mg (IR)tablet 2 × 75 mg (ER)capsules (ER)capsules Time (hours) (q 12 h) (q 24 hr) (q 24 h) 0 62.3 55.0 55.8 0.5 76.3 1 135.6 53.3 53.2 2 212.1 69.8 70.9 4 162.0 138.6 133.3 6 114.6 149.0 143.5 8 86.7 129.3 129.5 10 118.4 114.4 12 51.9 105.1 105.8 12.5 74.7 13 127.5 14 161.3 90.5 91.3 16 134.6 78.2 78.5 18 106.2 20 83.6 62.7 63.3 24 57.6 56.0 57.3
[0039] Table 2 shows that the plasma levels of two 75 mg/capsule venlafaxine hydrochloride ER capsules and one 150 mg/capsule venlafaxine hydrochloride ER capsule provide very similar blood levels. The data also show that the plasma level after 24 hours for either extended release regimen is very similar to that provided by two immediate release 75 mg tablets of venlafaxine hydrochloride administered at 12 hour intervals.
[0040] Further, the plasma levels of venlafaxine obtained with the extended release formulation do not increase to the peak levels obtained with the conventional immediate release tablets given 12 hours apart. The peak level of venlafaxine from (ER), somewhat below 150 ng/ml, is reached in about six hours, plus or minus two hours, based upon this specific dose when administered to patients presently under treatment with venlafaxine hydrochloride (IR). The peak plasma level of venlafaxine, somewhat over 200 ng/ml, following administration of (IR) is reached in two hours and falls rapidly thereafter.
[0041] Table 3 shows venlafaxine blood plasma levels in male human subjects having a zero initial blood plasma level. Again, a peak blood plasma concentration of venlafaxine is seen at about 6 hours after dosing with venlafaxine hydrochloride extended release capsules in the quantities indicated. The subjects receiving the single 50 mg immediate release tablet showed a peak plasma level occurring at about 4 hours. For comparative purposes, the plasma levels of venlafaxine for subjects receiving the conventional formulated tablet can be multiplied by a factor of three to approximate the plasma levels expected for a single dose of 150 mg. conventional formulation.
TABLE 3 Plasma Blood Levels in Human Males Having No Prior Venlafaxine Blood Level 2 × 75 mg ER 1 × 150 mg ER Time (Hours) 1 × 50 mg IR tablet capsules capsule 0 0 0 0 1 27.87 1.3 0 1.5 44.12 6.0 2.2 2 54.83 20.6 12.8 4 66.38 77.0 81.0 6 49.36 96.5 94.4 8 30.06 93.3 86.9 10 21.84 73.2 72.8 12 15.91 61.3 61.4 14 13.73 52.9 51.9 16 10.67 47.5 41.1 20 5.52 35.2 34.0 24 3.56 29.3 28.5 28 2.53 23.4 22.9 36 1.44 11.9 13.5 48 0.66 5.8 5.2
[0042] The blood plasma levels of venlafaxine were measured according to the following procedure. Blood samples from the subjects were collected in heparinized evacuated blood tubes and the tubes were inverted gently several times. As quickly as possible, the tubes were centrifuged at 2500 rpm for 15 minutes. The plasma was pipetted into plastic tubes and stored at −20° C. until analysis could be completed.
[0043] To 1 mL of each plasma sample in a plastic tube was added 150 μL of a stock internal standard solution (150 μg/ml). Saturated sodium borate (0.2 mL) solution was added to each tube and vortexed. Five mL of ethyl ether was added to each tube which were then capped and shaken for 10 minutes at high speed. The tubes were centrifuged at 3000 rpm for 5 minutes. The aqueous layer was frozen in dry ice and the organic layer transferred to a clean screw cap tube. A 0.3 mL portion of 0.01 N HCl solution was added to each tube and shaken for 10 minutes at high speed. The aqueous layer was frozen and the organic layer removed and discarded. A 50 μL portion of the mobile phase (23:77 acetonitrile:0.1M monobasic ammonium phosphate buffer, pH 4.4) was added to each tube, vortexed, and 50 μL samples were injected on a Supelco Supelcoil LC-8-DB, 5 cm×4.6 mm, 5 p column in a high pressure liquid chromatography apparatus equipped with a Waters Lambda Max 481 detector or equivalent at 229 nm. Solutions of venlafaxine hydrochloride at various concentrations were used as standards.
EXAMPLE NO. 5
[0044] Manufactured by the techniques described herein, another preferred formulation of this invention comprises spheroids of from about 30% to about 35% venlafaxine hydrochloride and from about 0.3% to about 0.6% hydroxypropylmethylcellulose. These spheroids are then coated with a film coating, as described above, to a coating level of from about 5% to about 9%, preferably from about 6% to about 8%. A specific formulation of this type comprises spheroids of about 33% venlafaxine hydrochloride and about 0.5% hydroxypropylmethylcellulose, with a film coating of about 7%.
[0045] Lower dosage compositions or formulations of this invention may also be produced by the techniques described herein. These lower dosage forms may be administered alone for initial titration or initiation of treatment, prior to a dosage increase. They may also be used for an overall low-dose administration regimen or in combination with higher dosage compositions, such as capsule formulations, to optimize individual dosage regimens.
[0046] These lower dose compositions may be used to create encapsulated formulations, such as those containing doses of venlafaxine hydrochloride from about 5 mg to about 50 mg per capsule. Particular final encapsulated dosage forms may include, but are not limited to, individual doses of 7.5 mg, 12.5 mg, 18.75 mg, or 28.125 mg of venlafaxine HCl per capsule.
[0047] The spheroids useful in these lower dose formulations may comprise from about 5% to about 29.99% venlafaxine HCl, preferably from about 5% to about 25%, from about 75% to about 95% microcrystalline cellulose, and, optionally from about 0.25% to about 1.0% hydroxypropylmethylcellulose. The spheroids may be coated as described above, preferably with a film coating of from about 5% to about 10% by weight. In some preferred formulations, the spheroids comprise the cited venlafaxine HCl and microcrystalline cellulose, with no hydroxypropylmethyl cellulose.
EXAMPLE NO. 6
[0048] Spheroids comprising 16.5% venlafaxine HCl and 83.5% microcrystalline cellulose were mixed with approximately 50% water (w/w) to granulate in a Littleford Blender Model FM-50E/1Z (Littleford Day Inc., P.O. Box 128, Florence, Ky. 41022-0218, U.S.A.) at a fixed speed of 180 rpm. The blended material was extruded through a 1.25 mm screen using a Nica extruder/speronization machine (Aeromatic-Fielder Division, Niro Inc., 9165 Rumsey Rd., Columbia, Md. 21045, U.S.A.) for a 12/20 mesh cut after drying. Two portions of the resulting spheroids were coated with a 5% and 7% coating level, respectively, by techniques described above using the coating formulation:
Ingredient % (w/w) Methylene Chloride 60.000 Methanol Anhydrous 35.500 Ethylcellulose, NF, HG 2834, 50 cps 3.825 Hydroxypropyl Methylcellulose, 2910 USP, 0.675 6 cps
[0049] These 5% and 7% coated lots were tested for dissolution on a Hewlett Packard automated dissolution system over a 24 hour period, resulting in the following dissolution patterns:
EXAMPLE NO. 7 % Dissoluded % Dissolved Time/hr 16.5%/5% 16.5%/7% 2 12.4 5.6 4 42.8 25.4 8 70.7 60.4 12 82.2 75.4 24 94.3 92.7
[0050] A formulation of spheroids containing 8.25% venlafaxine HCl and 91.75% microcrystalline cellulose was prepared according to the techniques of Example No. 6 and coated with a 5% film coating. In the Hewlett Packard automated dissolution system these spheroids provided the following dissolution profile:
% Dissolved Time/hr 8.25%/5% 2 4.4 4 24.2 8 62.9 12 77.8 24 93.5
[0051] Thus, the desired dissolution rates of sustained release dosage forms of venlafaxine hydrochloride, impossible to achieve with hydrogel tablet technology, has been achieved with the film-coated spheroid compositions of this invention.
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This invention relates to a 24 hour extended release dosage formulation and unit dosage form thereof of venlafaxine hydrochloride, an antidepressant, which provides better control of blood plasma levels than conventional tablet formulations which must be administered two or more times a day and further provides a lower incidence of nausea and vomiting than the conventional tablets. More particularly, the invention comprises an extended release formulation of venlafaxine hydrochloride comprising a therapeutically effective amount of venlafaxine hydrochloride in spheroids comprised of venlafaxine hydrochloride, microcrystalline cellulose and, optionally, hydroxypropylmethylcellulose coated with a mixture of ethyl cellulose and hydroxypropylmethylcellulose.
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FIELD OF THE INVENTION
The invention generally relates to a process and apparatus for gas phase polymerization of olefins in a fluidized bed reactor. The process and apparatus employ a vertically oriented fines ejector in order to reduce fouling and reactor downtime.
BACKGROUND OF THE INVENTION
In a typical gas-phase, fluidized bed olefin polymerization process, fine polymer particles are carried overhead from the reactor and are removed from the recycle gas stream using cyclone or centrifugal separators. The collected fines are drawn from the bottom of the separator using an ejector and from there are returned to the reactor. Such a system is described in U.S. Pat. No. 4,882,400; the entire content of which is hereby incorporated by reference.
Ejectors currently in use and discussed specifically in the '400 patent have a horizontal design. A horizontally oriented fines ejector is shown in FIG. 1 . In a typical horizontal fines ejector 10 , a gas stream 11 enters the ejector 10 horizontally as shown in FIG. 1 . The gas stream 11 provides a motive force to draw fines and gas 12 from the separator (not shown), incorporating them in the gas stream 11 , and conveying them 13 to the reactor (not shown) into which they are subsequently re-injected.
In a continuous gas-phase, fluidized bed polyolefin polymerization process, it is common that gas loop piping and equipment would foul to the extent that a shutdown is periodically required for cleaning. Fouling is especially severe in the horizontal fines ejector 10 as the polymer powder-laden gas stream 12 from the fines separators (not shown) is forced to change direction, typically 90°, within the ejector 10 . The powder and sometimes even sheets of polymer tend to build-up in area 14 and reduce the efficiency or even plug the ejector 10 .
Fouling is so severe in the conventional-design ejector that cleaning to remove polymer build-up is required on average every two months, resulting in frequent plant shutdowns, excessive cleaning expenses, and unacceptable lost production. In extreme cases, heavy fouling of ejector internals will significantly impede ejector performance and has resulted in flow blockages and unplanned reactor shutdowns.
One of the aims of this invention, therefore, is to solve the problems associated with horizontal fines ejectors and extend the time between cleanings of the ejectors.
SUMMARY OF THE INVENTION
In one aspect, the invention provides a process for polymerizing olefins. The process comprises:
(a) contacting one or more olefins with a catalyst in a fluidized bed reactor under polymerization conditions to form an ascending gas stream comprising fine polymer particles and unreacted olefins; (b) passing the ascending gas stream to a fines separator to separate the fine polymer particles from the unreacted olefins; (c) passing the fine polymer particles from the fines separator to a vertically oriented fines ejector; and (d) introducing a motive gas into the vertically oriented fines ejector to convey the fine polymer particles back to the fluidized bed reactor.
In another aspect, the invention provides an apparatus for polymerizing olefins. The apparatus comprises:
(a) a fluidized bed reactor for contacting one or more olefins with a catalyst under polymerization conditions to form an ascending gas stream comprising fine polymer particles and unreacted olefins; (b) a fines separator in fluid communication with the fluidized bed reactor for separating the fine polymer particles from the unreacted olefins; and (c) a vertically oriented fines ejector in fluid communication with the fines separator for conveying the fine polymer particles back to the fluidized bed reactor.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a conventional horizontally oriented fines ejector.
FIG. 2 is a cross-sectional view of a vertically oriented fines ejector according to the invention.
FIG. 3 is a cross-sectional view of another vertically oriented fines ejector according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
In a first aspect, the invention provides a process for polymerizing olefins. The process comprises:
(a) contacting one or more olefins with a catalyst in a fluidized bed reactor under polymerization conditions to form an ascending gas stream comprising fine polymer particles and unreacted olefins; (b) passing the ascending gas stream to a fines separator to separate the fine polymer particles from the unreacted olefins; (c) passing the fine polymer particles from the fines separator to a vertically oriented fines ejector; and (d) introducing a motive gas into the vertically oriented fines ejector to convey the fine polymer particles back to the fluidized bed reactor.
The olefins suitable for use in the invention include, for example, those containing from 2 to 16 carbon atoms. The olefins can be polymerized to form homopolymers, copolymers, terpolymers, and the like. Particularly preferred for preparation herein are polyethylenes. Such polyethylenes include homopolymers of ethylene and copolymers of ethylene and at least one alpha-olefin wherein the ethylene content is at least about 50% by weight of the total monomers involved. Exemplary alpha-olefins that may be utilized are propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 4-methyl-1-pentene, 1-decene, 1-dodecene, 1-hexadecene and the like. Also utilizable herein are polyenes such as 1,3-hexadiene, 1,4-hexadiene, 1,5-hexadiene, cyclopentadiene, dicyclopentadiene, 4-vinylcyclohex-1-ene, 1,5-cyclooctadiene, 5-vinylidene-2-norbornene, 5-vinyl-2-norbornene, and olefins formed in situ in the polymerization medium. When olefins are formed in situ in the polymerization medium, the formation of polyethylenes containing long chain branching may occur.
In the present invention, any catalyst for polymerizing olefins may be used. Preferably the olefin polymerization catalyst comprises at least one metal selected from Groups 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 and 13 of the Periodic Table of the Elements. Exemplary metals are titanium, zirconium, vanadium, iron, chromium, nickel and aluminum. The olefin polymerization catalyst may be neutral or cationic.
Exemplary of such polymerization catalysts are:
1. Any compound containing a Group 6 element. Preferred are chromium containing compounds. Exemplary are chromium oxide catalysts which polymerize ethylene to high molecular weight high density polyethylenes (HDPE) having a broad molecular weight distribution. These catalysts are typically based on Cr(6+) and are supported on a carrier. Further exemplary are organochromium catalysts such as bis(triphenylsilyl)chromate supported on silica and activated with organoaluminum compounds, and bis(cyclopentadienyl)chromium supported on silica.
2. Ziegler-Natta catalysts which typically contain a transition metal component and an organometallic co-catalyst such as an organoaluminum compound.
3. An olefin polymerization catalyst that polymerizes olefins to produce interpolymers of olefins having a molecular weight distribution (MWD) of from 1 to 2.5.
4. Metallocene catalysts which contain a transition metal component having at least one moiety selected from substituted or unsubstituted cyclopentadienyl, substituted or unsubstituted pentadienyl, substituted or unsubstituted pyrrole, substituted or unsubstituted phosphole, substituted or unsubstituted arsole, substituted or unsubstituted boratabenzene, and substituted or unsubstituted carborane, and an organometallic co-catalyst that is typically alkyl aluminoxane, such as methyl aluminoxane, or an aryl substituted boron compound.
5. Any compound containing a Group 13 element. Preferred are aluminum containing compounds. Exemplary are catalysts of the type described in U.S. Pat. No. 5,777,120, such as cationic aluminum alkyl amidinate complexes with an organometallic co-catalyst that is typically alkylaluminoxane, such as methylaluminoxane, or an aryl substituted boron containing compound.
6. Any compound containing a Group 10 element. Preferred are nickel containing compounds. Exemplary are catalysts of the type described in U.S. Pat. No. 5,866,663, such as cationic nickel alkyl diimine complexes with an organometallic co-catalyst that is typically alkylaluminoxane, such as methylaluminoxane, or an aryl substituted boron containing compound. Further exemplary are catalysts of the type described in Organometallics, 1998, Volume 17, pages 3149-3151, such as neutral nickel alkyl salicylaldiminato complexes.
7. Any compound containing a Group 8 element. Preferred are iron containing compounds. Exemplary are catalysts of the type described in the Journal of the American Chemical Society, 1998, Volume 120, pages 7143-7144, such as cationic iron alkyl pyridinebisimine complexes with an organometallic co-catalyst that is typically alkylaluminoxane, such as methylaluminoxane, or an aryl substituted boron containing compound.
8. Any compound containing a Group 4 element. Preferred are titanium and zirconium containing compounds. Exemplary are catalysts of the type described in the Journal of the American Chemical Society, 1996, Volume 118, pages 10008-10009, such as cationic titanium alkyl diamide complexes with an organometallic co-catalyst that is typically alkylaluminoxane, such as methylaluminoxane, or an aryl substituted boron containing compound.
The above catalysts are, or can be, supported on inert porous particulate carriers, known in the art.
Any fluidized bed reactor for polymerizing olefins may be used in the process of the present invention. Typically, such a fluidized bed reactor comprises a reaction zone and a so-called velocity reduction zone. The reaction zone comprises a bed of growing polymer particles, formed polymer particles, and a minor amount of catalyst particles fluidized by a continuous flow of gaseous monomer and diluent to remove heat of polymerization from the reaction zone. A suitable rate of gas flow may be readily determined by simple experiment.
The polymerization is generally carried out at a pressure of about 0.5 to about 5 MPa, and at a temperature of from about 30° C. to about 150° C. The gas mixture passing through the fluidized bed polymerization reactor may contain, among the olefin(s) to be polymerized, dienes, hydrogen, and a gas that is inert towards the catalyst such as nitrogen, methane, ethane and/or propane. The gas mixture passes through the fluidized bed as a rising stream, with a fluidization velocity that is generally between 2 and 8 times the minimum fluidization velocity, e.g., between 0.2 and 0.8 m/s.
An ascending gas stream, which comprises entrained polymer particles and unreacted olefins, leaving the reaction zone is passed to the velocity reduction zone where entrained particles are removed. Finer entrained polymer particles and dust in the ascending gas stream are passed to a fines separator such as a cyclone and/or fine filter to separate the fine polymer particles from the unreacted olefins. The gas containing unreacted olefins from the fines separator can then be passed through a heat exchanger wherein the heat of polymerization is removed, compressed in a compressor, and then returned to the reaction zone in a recycle loop. Optionally, some of the recirculated gases may be cooled and compressed to form liquids that increase the heat removal capacity of the circulating gas stream when readmitted to the reaction zone.
According to the invention, the fine polymer particles separated from the unreacted olefins are passed to a vertically oriented fines ejector. A “vertically oriented fines ejector” refers to a fines ejector that does not force the stream of fines flowing through it to change direction, e.g., 90°. In preferred embodiment, the fines flow substantially vertically into the vertically oriented fines ejector and continue to flow substantially vertically upon exiting the ejector.
A motive gas is introduced into the vertically oriented fines ejector to convey the fine polymer particles back to the fluidized bed reactor. The motive gas may contain a gas that is inert towards the catalyst employed during the polymerization reaction, such as nitrogen. The motive gas may also contain the olefins that are introduced into the reactor. Preferably, a fraction of the gas from the recycle loop containing unreacted olefins that has been cooled and compressed is used as part of or all of the motive gas.
Bearing in mind the fact that the fine polymer particles reintroduced into the fluidized bed reactor can contain a high-activity catalyst, it is preferred to use a motive gas whose temperature is at least 15° C. lower than the polymerization temperature in the fluidized bed reactor. This is particularly preferred when the motive gas contains at least one olefin in order to avoid a premature polymerization reaction in the vertically oriented fines ejector or in the reintroduction pipework, which could cause blocking of the ejector or pipework.
In one embodiment of the invention, the vertically oriented fines ejector has the configuration shown in FIG. 2 . In FIG. 2 , fine polymer particles and gas 22 exiting the fines separator (not shown) enter the vertically oriented fines ejector 20 in a substantially vertical direction. Motive gas 21 is introduced into the fines ejector 20 as an annular stream 24 , which envelops the stream of fine polymer particles 22 entering the ejector 20 and propels the particles 23 in a substantially vertical direction back to the fluidized bed reactor. In ejector 20 , both the entering fine polymer particles 22 and the exiting particles 23 travel in substantially the same general direction so that there is minimal or no internal surface area for the fine polymer particles to collect and build up in to cause unwanted fouling and plugging of the ejector 20 . Additionally, since the powder-laden gas 22 entering the converging section of the ejector is conveyed in an annular envelop of the motive gas 24 , there is minimal contact between the polymer particles and the ejector internal surfaces.
In another embodiment of the invention, the vertically oriented fines ejector has the configuration shown in FIG. 3 . In FIG. 3 , fine polymer particles and gas 32 exiting the fines separator (not shown) enter the vertically oriented fines ejector 30 in a substantially vertical direction. Motive gas 31 is introduced into the fines ejector 30 through nozzle 34 as a stream inside of the stream of flowing fine polymer particles 32 entering the ejector 30 . The motive gas 31 propels the particles 33 in a substantially vertical direction back to the fluidized bed reactor. In ejector 30 , both the entering fine polymer particles 32 and the exiting particles 33 travel in substantially the same general direction so that there is minimal or no area for the fine polymer particles to collect and build up in to cause unwanted fouling and plugging of the ejector 30 .
The motive gas is supplied in an amount sufficient to provide the compression needed to pull streams 12 , 22 , or 32 from the fines separator and to deliver streams 13 , 23 , and 33 to the reactor. The precise amount depends on the particular process conditions and equipment employed, but may be determined by persons skilled in the art.
In a second aspect, the invention provides an apparatus for polymerizing olefins. The apparatus comprises:
(a) a fluidized bed reactor for contacting one or more olefins with a catalyst under polymerization conditions to form an ascending gas stream comprising fine polymer particles and unreacted olefins; (b) a fines separator in fluid communication with the fluidized bed reactor for separating the fine polymer particles from the unreacted olefins; and (c) a vertically oriented fines ejector in fluid communication with the fines separator for conveying the fine polymer particles back to the fluidized bed reactor.
The apparatus can further comprise a heat exchanger for cooling the unreacted olefins from the fines separator, a compressor for compressing the cooled unreacted olefins, and a conduit for recyling the cooled and compressed unreacted olefins back to the fluidized bed reactor.
The apparatus can also further comprise a conduit for conveying at least a portion of the cooled and compressed unreacted olefins to the vertically oriented fines ejector.
In one embodiment, as seen in FIG. 2 , the vertically oriented fines ejector 20 comprises an annulus 24 for introducing an annular stream of a motive gas 21 around a stream of the fine polymer particles 22 .
In another embodiment, as seen in FIG. 3 , the vertically oriented fines ejector 30 comprises a nozzle 34 for introducing a motive gas 31 inside a stream of the fine polymer particles 32 .
The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.
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A process and apparatus for gas phase polymerization of olefins in a fluidized bed reactor are disclosed. The process and apparatus employ a vertically oriented fines ejector in order to reduce fouling and reactor downtime.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority to GB 0524887.7, filed Dec. 6, 2005 and PCT/SE2006/001339, filed Nov. 28, 2006.
FIELD OF THE INVENTION
The present invention relates to an arrangement for detecting a crash, and more particularly relates to an arrangement, to be installed in a motor vehicle, for detecting a crash and evaluating the severity of the crash, and for providing a signal to actuate a safety device to protect an occupant of the vehicle in the event that a crash situation occurs.
BACKGROUND OF THE INVENTION
Conventional crash detection arrangements typically comprise a crash sensor and a control unit. The crash sensor is usually an accelerometer which is connected to a processor within the control unit to provide a signal to the processor which is indicative of the acceleration applied to the vehicle, for instance by forces arising during a crash situation. The control unit is usually provided with a first comparator which compares the signal from the accelerometer with a predetermined acceleration value, which is set at a level such that values of acceleration higher than the predetermined value would indicate that the vehicle is involved in a crash situation. The processor is configured to process the signal from the accelerometer when the first comparator indicates that the signal from the accelerometer is in excess of the predetermined acceleration value. The processor processes the signal for a predetermined length of time (as explained in more detail below) following a determination that the acceleration has first risen above the predetermined acceleration value, and this processing generally determines an amount by which the velocity of the vehicle changes during the predetermined length of time.
A second comparator compares the result of the processing of the signal with a predetermined threshold. If the second comparator finds the result of the signal processing to be in excess of the predetermined threshold (i.e. the velocity has changed by more than a pre-set amount), the second comparator generates a trigger signal which is indicative of the occurrence of a crash situation which is severe enough to warrant activation of a safety device, such as an air-bag. The trigger signal is then transmitted to a safety device to actuate the safety device to protect an occupant of the vehicle.
Referring now to FIG. 1 of the accompanying drawings, the variation in the acceleration a of a vehicle is plotted against time during a crash, with a first curve a 1 which corresponds to a high speed crash (e.g., a crash at 37 mph) and a second curve a 2 which corresponds to a relatively low speed crash (e.g., a crash at 9 mph).
If a conventional crash detection arrangement, such as the arrangement described above, is installed in a vehicle which is involved in either the high speed crash or the low speed crash, the processor will begin to process the acceleration signal a 1 or a 2 when first comparator indicates that the acceleration signal a 1 or a 2 is in excess of a predetermined acceleration value a 0 . The times at which the processor starts to process the acceleration signal a 1 or a 2 , are indicated respectively at times t 01 and t 02 on FIG. 1 .
The processor processes the signal a 1 or a 2 by integrating the signal a 1 or a 2 over a set length of time to determine the change in velocity Δv of the vehicle, according to the following equation:
Δ v =(∫( a−a 0 ) dt )
The resultant value indicative of the change in velocity Δv is then compared, by the second comparator, with a predetermined threshold Δv T .
If the second comparator detects the change in velocity Δv to be in excess of the predetermined threshold Δv T , (i.e. Δv>Δv T ) the second comparator generates a trigger signal which is transmitted to the safety device to actuate the safety device to protect an occupant of the vehicle.
Referring now to FIG. 2 , the change in velocity Δv is plotted against time, with a first curve Δv 1 corresponding to the integral of the first curve a 1 of FIG. 1 , (i.e. the high speed crash) and a second curve Δv 2 corresponding to the integral of the second curve a 2 of FIG. 1 (i.e. the low speed crash). It can be seen, from FIG. 2 , that the curves Δv 1 and Δv 2 each start at the respective times t 01 and t 02 , which each correspond to the times at which the acceleration a 1 or a 2 first exceeds the predetermined acceleration value a 0 , and hence the time at which the processor starts processing the signal a 1 or a 2 .
A determination must be made within an appropriate period of time (e.g. 30 ms) following the time at which the acceleration rises above a 0 as to whether the crash situation requires the actuation of a safety device. If the actuation of the safety device is not triggered within an appropriately short period of time, the benefit of the safety device may be lost and the actuation thereof may be positively harmful to a vehicle occupant.
As can be seen from FIG. 2 , the changes in velocity Δv 1 and Δv 2 exceed the predetermined threshold Δv T for respectively the high speed crash and the low speed crash at respective trigger times t T1 and t T2 , which correspond to approximately 30 ms after t 01 and t 02 respectively.
The actuation of the safety device is desirable in the case of the high speed crash, represented by the first curves a 1 and Δv 1 , as the forces (proportional to a 1 ) arising from such a high speed crash will become large, at the end of the crash event meaning that it is likely that an occupant will need protection. However, it may not be desirable to trigger the safety device as a result of the low speed crash represented by the second curves a 2 and Δv 2 , as it is unlikely that an occupant will need the protection provided by the safety device since the forces arising from the low speed crash are likely to be minimal.
Unfortunately, as can be seen from FIGS. 1 and 2 , the acceleration in a 30 ms time period following the moment at which the acceleration rises above the threshold is largely dependent on the stiffness of parts of the vehicle, and is not heavily dependent upon the severity of the impact. In a severe impact, such as a high speed crash, the acceleration will continue to rise after the 30 ms interval has passed (following a short “plateau” phase) but, as discussed above, it is not desirable to wait longer than the 30 ms interval this before a decision must be taken as to whether to actuate the safety device.
In the case of a high speed crash, therefore, it is important to actuate the safety device very soon after the crash has occurred, so that the safety device may be fully deployed to protect an occupant of the vehicle from forces arising from the crash. In order to provide early actuation of the safety device, the predetermined threshold Δv T can be set at a relatively low level so that the time taken for the change in velocity Δv to rise to the low predetermined threshold Δv T is relatively short. However, if a low value of the predetermined threshold Δv T is chosen, the change in velocity Δv 2 in the case of a low speed crash will also rise to the level of the predetermined threshold Δv T during the 30 ms processing period. Thus, selecting a low value for the predetermined threshold Δv T can result in the safety device being unnecessarily actuated in the event of a low speed crash.
One way to prevent the safety device from being actuated in the event of a low speed crash would be to raise the predetermined threshold Δv T to a level which the change in velocity Δv 2 in a low speed crash will not reach. In this case, the safety device would only be actuated by the relatively large change in velocity Δv 1 , arising from a high speed crash, which reaches the higher predetermined threshold Δv T . However, the raising of the predetermined threshold Δv T means that the length of time until which the change in velocity Δv takes to reach the threshold is increased, thus increasing the length of time after which the crash occurs when the safety device is actuated.
Therefore, the need arises for a crash detection arrangement which can actuate a safety device swiftly to protect an occupant of a vehicle during a high speed crash, but which will not actuate the safety device unnecessarily in response to a relatively low speed crash.
The present invention seeks to provide an improved arrangement for determining the severity of a crash at an early stage.
According to one aspect of the present invention, there is provided a crash detection arrangement, to be installed in a motor vehicle, for detecting a crash and providing a control signal for controlling a safety device in the event that a crash is detected, the arrangement comprising an accelerometer and a control unit, the accelerometer being arranged to supply a signal to the control unit which is indicative of the acceleration of the vehicle, characterised by the control unit being adapted to: calculate a classification parameter based on the value of the signal from the accelerometer during a classification time period, which includes an interval of time before an initiation criterion was fulfilled; modify a crash evaluation algorithm in dependence upon the classification parameter; and perform the crash evaluation algorithm upon fulfillment of the initiation criterion to produce the control signal.
Advantageously, the control unit is adapted to compare the signal from the accelerometer with a predetermined acceleration value, and the initiation criterion is fulfilled when the signal from the accelerometer first exceeds the predetermined acceleration value.
Preferably, the crash evaluation algorithm comprises processing of the signal from the accelerometer for an evaluation time period which follows the time at which the initiation criterion is fulfilled.
Conveniently, the control signal comprises an actuation signal, an evaluation parameter is calculated by the crash evaluation algorithm, the step of modifying the crash evaluation algorithm comprises the steps of setting a threshold value in dependence upon the value of the classification parameter, and the crash evaluation algorithm comprises comparing the evaluation parameter with the threshold value to provide an actuation signal in dependence upon the result of the comparison.
Advantageously, the crash evaluation algorithm comprises integration of the sensed value of acceleration, and an actuation signal is provided if the result of the integration is greater than the threshold value.
Conveniently, the control unit is configured to set the threshold value to be equal to a low threshold value when the classification parameter indicates that the rise in acceleration before fulfillment of the initiation criterion is relatively fast, and to be equal to a high threshold value when the classification parameter indicates that the rise in acceleration before fulfillment of the initiation criterion is relatively slow.
Advantageously, the classification parameter is based at least partly on an integration of the sensed value of acceleration during the classification time period, or on an average of the sensed value of acceleration during the classification time period.
Preferably, the control unit is configured to set the threshold value to be equal to the high threshold value when the classification parameter is relatively high and to be equal to the low threshold value when the classification parameter is relatively low.
Alternatively, the classification parameter is based partly on an average of a derivative of the sensed value of acceleration during the classification time period.
Conveniently, the control unit is configured to set the threshold value to be equal to the high threshold value when the classification parameter is relatively low and to be equal to the low threshold value when the classification parameter is relatively high.
Advantageously, the determination as to whether the classification parameter is relatively high or relatively low is made by comparing the classification parameter with a predetermined constant.
Preferably, the threshold value is proportional to the classification parameter.
Conveniently, the classification parameter provides an indication of the rapidity of the rise in acceleration before fulfillment of the initiation criterion.
Advantageously, the control unit is configured to set the threshold value according to a formula which is dependent upon the classification parameter.
Preferably, the control signal comprises a variable output value.
Conveniently, the control unit repeatedly re-calculates the classification parameter.
Advantageously, the classification parameter is re-calculated at regular intervals.
Preferably, the classification parameter is calculated in response to the fulfillment of the initiation criterion.
Conveniently, the arrangement comprises a memory which is configured to store sensed values of acceleration.
Advantageously, the memory is configured to store, at a given moment, values of acceleration that were sensed during a predetermined length of time preceding the given moment.
Preferably, upon fulfillment of the initiation criterion, the predetermined length of time corresponds to the classification time period.
Conveniently, the classification parameter is calculated using values of acceleration stored in the memory.
Advantageously, the classification time period falls entirely before the fulfillment of the initiation criterion.
Preferably, the classification time period has a length of approximately 8 ms.
Another aspect of the present invention provides a crash detection method for detecting whether a vehicle is involved in a crash and providing a control signal for controlling of a safety device in the event that a crash is detected, the method comprising the step of: providing an accelerometer which supplies a signal which is indicative of the acceleration of the vehicle; and being characterised by the steps of calculating a classification parameter based on the value of the signal from the accelerometer during a classification time period, which includes an interval of time before an initiation criterion was fulfilled; modifying a crash evaluation algorithm in dependence upon the classification parameter; and upon fulfillment of the initiation criterion, performing the crash evaluation algorithm to produce the control signal.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the invention may be more readily understood, and so that further features thereof may be appreciated, the invention will now be described, by way of example, with reference to the accompanying drawings in which:
FIG. 1 is a graphical representation of the acceleration of a vehicle against time in a high speed crash and in a low speed crash,
FIG. 2 is a graphical representation of the calculated change in velocity against time in a high speed crash and a low speed crash,
FIG. 3 is a diagrammatic view of an arrangement for detecting a crash in accordance with a preferred embodiment of the invention installed in a motor vehicle,
FIG. 4 is a block diagram of a control arrangement in accordance with the preferred embodiment of the invention,
FIG. 5 is a graphical representation of the acceleration of the vehicle against time, during an initial stage after a collision, in the case of a high speed crash and a low speed crash, and
FIG. 6 is a graphical representation corresponding to FIG. 2 , but including a high predetermined threshold and a low predetermined threshold.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 3 , a crash detection arrangement 1 embodying the present invention is installed in a motor vehicle 2 for detecting a crash situation. The arrangement 1 incorporates an accelerometer 3 which is configured to measure the acceleration of the vehicle 2 . The accelerometer 3 is connected to supply a signal which is indicative of the acceleration of the vehicle 2 to a control unit 4 . The control unit 4 processes the signal from the accelerometer 3 (in a manner which will be discussed below) to determine whether a crash situation is occurring. The control unit 4 is connected to a safety device 5 to provide a control to the safety device 5 in the event that a crash situation is detected, to control the operation of the safety device 5 to protect an occupant of the vehicle. The safety device 5 shown here is in the form of a front air-bag unit which may be actuated to inflate an air-bag, but it is to be appreciated that the safety device 5 may be any other type of safety device, for instance a safety belt pretensioner or a side air-bag unit.
The control unit 4 incorporates a first processing arrangement 6 which is configured to integrate the signal a from the accelerometer 3 . The first processing arrangement 6 is provided with an input to receive a start signal from a comparator 7 . The comparator 7 is configured to provide the start signal when the acceleration signal a first exceeds the predetermined acceleration value a 0 . When the sensed value of acceleration rises above the acceleration value a 0 , the processing arrangement 6 processes the acceleration signal a for an evaluation time period to determine the change in velocity Δv of the vehicle 2 over a period of time, as discussed above. The length of the classification time period may vary in dependence upon the manner in which the result of the processing of the acceleration signal is to be used, as will be discussed below.
Thus, the first processing arrangement 6 processes the acceleration signal a for the evaluation time period to generate a value which is indicative of the change in velocity Δv during that period of time. As discussed above, this may be achieved by integrating the sensed value of the increase in acceleration during the evaluation time period. In preferred embodiments of the invention, the first processing arrangement 6 then compares the calculated change in velocity Δv with a predetermined threshold Δv T . If the change in velocity Δv is greater than the predetermined threshold Δv T , it has been determined that the vehicle 2 is involved in a crash which is sufficiently severe to warrant activation of the safety device 5 , and the first processing arrangement 6 transmits an actuation signal to the safety device 5 . These embodiments are particularly applicable to use of the invention with safety devices that require an actuation signal, for instance an air-bag unit. Other safety devices may require a control signal which may take several different values, or indeed be continuously variable, as will be discussed below.
In preferred embodiments of the invention, the sensed acceleration of the vehicle exceeding a 0 comprises an initiation criterion, which indicates that the vehicle is involved in a crash situation. Once the initiation criterion is fulfilled, the first processing arrangement 6 performs a crash evaluation algorithm to provide an evaluation parameter, and in the above-described embodiment the evaluation parameter comprises a result of integrating the sensed value of acceleration during the evaluation time period. This evaluation parameter may, as discussed above, then the compared with a threshold value to determine whether an actuation signal should be provided to the safety device 5 .
The control unit 4 further incorporates a second processing arrangement 8 which is configured to process the signal a from the accelerometer 3 over a classification time period, which in preferred embodiments has a length of around 8 ms. In such embodiments, at any given moment, the classification time period corresponds at least approximately to the 8 ms preceding that moment. This calculation is continuously updated, and for instance could be updated for each new sample of acceleration that is taken. A typical interval between samples is around 0.5 ms.
In embodiments of the present invention, the second processing arrangement 8 is configured to integrate the signal a from the accelerometer 3 for consecutive and successive periods of time corresponding to the classification time period. The second processing arrangement 8 once again integrates the signal a from the accelerometer 3 over the classification time period, which in these embodiments may be at least approximately 8 ms, to determine a value k to be used as a classification parameter. The second processing arrangement 8 therefore continually calculates values of k for successive time periods even when the sensed value of acceleration a is below the predetermined acceleration value a 0 . Thus, at any moment in time, irrespective of the acceleration of the vehicle, the second processing arrangement 8 will recently have calculated a value of k for the preceding 8 ms, and it will be appreciated that the second processing arrangement 8 thus operates on data relating to a “sliding window” of time which falls just before the present time.
After the second processing arrangement 8 has generated the value k the second processing arrangement 8 passes the value k to a second comparator 9 . The second comparator 9 has an output connected to a memory unit 10 which is adapted to store a value which corresponds to the predetermined threshold Δv T .
In embodiments of the invention in which the control signal comprises an actuation signal, the second comparator 9 compares the value k with a predetermined constant k T , and if the second comparator 9 determines that the value k is less than the constant k T , the second comparator 9 passes a value to the memory unit 10 which corresponds to a low predetermined threshold Δv T1 . The memory unit 10 stores the low predetermined threshold Δv T1 until a further value is sent from the second comparator 9 . If the second comparator 9 determines that the value k from the second processing arrangement 8 is greater than the constant k T , the second comparator 9 passes a value to the memory unit 10 which corresponds to a high predetermined threshold value Δv T2 .
Alternatively, the threshold Δv T may be set in accordance with a formula which is dependent upon the value k, and thus may take more values than a high predetermined threshold Δv T2 or a low predetermined threshold Δv T1 . For instance, the threshold Δv T may be set to be proportional to k, or include a component which is proportional to k (for instance comprising a constant to which a factor is added, the factor being proportional to k). Alternatively, the threshold Δv T may be proportional to the √k, to k 2 , or be dependent in any other way upon k, as a skilled person will appreciate.
In these embodiments, the threshold Δv T that is set may be continuously variable, and hence may be set to be appropriate for any type of crash situation.
The memory unit 10 is also connected to the first processing arrangement 6 to provide the stored value of the predetermined threshold Δv T to the first processing arrangement 6 . Thus, it is to be appreciated that the threshold Δv T is set to either a low threshold Δv T1 or a high threshold Δv 2 in dependence upon the most recent value of k produced by the second processing arrangement 8 .
Referring now to FIG. 5 , the curves a 1 and a 2 representing respectively the acceleration of the vehicle in a high speed crash and a relatively low speed crash, have been plotted so that the curves a 1 and a 2 first intersect at a time t 01 or t 02 when each of the curves a 1 or a 2 first exceeds the predetermined acceleration value a 0 and the initiation criterion is thus fulfilled. The “sliding window” of 8 ms is indicated as being a period of 8 ms before the times t 01 and t 02 when the curves a 1 and a 2 first exceed the predetermined acceleration value a 0 . The values of the acceleration a of the vehicle during this 8 ms “sliding window” are the values of acceleration a which are processed by the second processing arrangement 8 . It is to be appreciated that as the second processing arrangement 8 carries out an integrating calculation over the classification time period to calculate the value k, the value k will correspond to the area beneath each of the curves a 1 and a 2 during the classification time period. It can be seen that, as the acceleration a of the vehicle rises more rapidly during the initial stages of a high speed crash situation represented by curve a 1 , as opposed to a low speed crash situation represented by curve a 2 , the area beneath the high speed crash curve a 1 is less than the area beneath the low speed crash curve a 2 over the classification time period. Thus, the value k calculated by the second processing arrangement 8 is less in the case of a high speed crash than the value k calculated during a low speed crash.
This difference in the calculated value of k relating to the classification time period preceding the rise of the acceleration a above the predetermined acceleration value a 0 can be used to differentiate, at an early stage, between a high speed crash and a low speed crash. The constant k T which is compared by the second comparator 9 with the value k is chosen so that when the value k is less than the constant k T , indicating that the sensed acceleration value rose quickly towards the end of the classification time period and thus that a high speed crash is occurring, the second comparator 9 passes a low threshold value Δv T1 to the memory unit 10 . Conversely if the value k is greater than the constant k T , indicating a rapidity in the rise in acceleration which is below the predetermined value, and thus a low speed crash, the second comparator passes a high predetermined threshold Δv T2 to the memory unit 10 .
Thus, the calculated value k is lower when it has been determined that the vehicle is involved in a high speed crash, thereby helping to ensure that a safety device is triggered effectively in this situation.
In the above description, the value k is generated by integrating the sensed acceleration over the classification time period. However, in alternative embodiments, the second processing arrangement may calculate a value for k by taking an average of values of acceleration during the classification time period. In these embodiments, a low value of k is indicative of a more severe crash.
A further alternative approach is to take an averages of the derivative of these acceleration values. In these embodiments, a shorter classification time period will generally be appropriate, and for instance a classification time period of around 4 ms may be used. This is because, over an 8 ms classification time period, the averages of the derivatives of the second acceleration for gentle and severe crashes are likely to be similar, because at the start of the 8 ms classification time period the sensed acceleration will be close to zero in both cases, and at the end of the 8 ms classification time period the sensed value of acceleration will have risen in both cases, but by a similar amount. Since the derivative of the sensed acceleration is effectively equal to the slope of the acceleration/time graph, it will be understood that the average slope over 8 ms will be similar or identical over 8 ms for severe and gentle crashes. In effect, the fact that, for a more severe crash, the sensed acceleration would have remained low for the first part of the classification time period and then risen relatively rapidly would not be detected.
If, however, a shorter classification time period, for example of 4 ms, is used, this distinction can be detected far more readily. In the case of a more gentle crash, the sensed acceleration will begin to rise before the start of the 4 ms classification time period, and will already have risen by a certain amount at the start of the 4 ms classification period and continue to rise relatively gently throughout the 4 ms classification time period.
By contrast, in the case of a more severe crash, the sensed acceleration is likely to be around zero at the start of the 4 ms classification period, and rise sharply during this period. The average of the derivative of the acceleration value will therefore be higher in the case of a more severe crash when a shorter classification time period such as this is used. In this embodiment, therefore, a high value of k is indicative of a more severe crash.
A skilled person will understand how the above-described method may be adapted to accommodate these alternative methods of generating the value of k.
Referring now to FIG. 6 , the change in velocity Δv can be seen against time for the case of a high speed crash and a low speed crash, indicated respectively by curves Δv 1 and Δv 2 . The high and low predetermined thresholds Δv T1 and Δv T2 are also indicated. It is to be appreciated that a high speed crash curve Δv 1 intersects the low predetermined threshold Δv T1 at a trigger time t T1 which is relatively soon after the start time t 01 . If the second comparator 9 sets the high predetermined threshold Δv T2 , it can be seen that the high predetermined threshold Δv T2 only intersects with the high speed crash curve Δv 1 and not the low speed crash curve Δv 2 . Thus, if the second processing arrangement 8 and the second comparator 9 determine that the crash is a low speed crash, with the value k being greater than the constant k T , the high predetermined threshold Δv T2 is selected to avoid the trigger signal being generated by the low predetermined threshold Δv T2 being exceeded. However, it is to be appreciated that the high predetermined threshold Δv T2 may be exceeded if a low speed crash subsequently changes in severity to become a severe or high speed crash. The arrangement 1 can thus be used to trigger the safety device 5 in the event of a low speed crash which subsequently develops into a severe or high speed crash.
Although the preferred embodiment described thus far only incorporates two predetermined threshold Δv T1 and Δv T2 , it is to be appreciated that other embodiments may utilise a greater number of predetermined thresholds, to distinguish more finely between different types of crash.
It will be noted that both Δv T1 and Δv T2 are “stepped” in shape on the graph of FIG. 6 , and hence vary with time. These thresholds may vary with time in order to increase the number of dangerous types of crash that are correctly detected, while correctly classifying less dangerous crashes, and a skilled person will appreciate how this may be achieved. In the example shown Δv T1 and Δv T2 are stepped, but part or all of either of these thresholds may vary continuously with time.
Whilst the preferred embodiment utilises a classification time period which is around 8 ms in length, it is to be understood that the classification time period may be any other length of time, which is greater or less than 8 ms (in particular, see the discussion above relating to the use of a shorter time period in certain embodiments). Also, although the second processing arrangement 8 of the preferred embodiment calculates the value k every 0.5 ms, in other embodiments the value k may be calculated after successive time intervals which are greater or less than 0.5 ms.
Indeed, the second processing arrangement 8 may calculate a value for k only when the sensed value of acceleration first rises above a 0 . Thus, in this embodiment a sliding window of data is stored, but this data is only processed as and when it is detected that a crash situation has arisen.
In the above, it is described that the crash evaluation algorithm decides whether or not an actuation is signal is provided to a safety device, and an example of a safety device that may receive an actuation signal is an air-bag, the actuation signal simply dictates whether or not the air-bag is inflated. However, the output of the crash evaluation algorithm could also control a continuous parameter, such as the force level of a seat belt force limiter, or the pressure of air which is introduced into an air-bag. Therefore, the crash evaluation algorithm need not simply output a parameter which is compared with a threshold, but may output an appropriate and continuously variable value which may be used by the control unit 4 to control a safety-device, as will be appreciated by a skilled person. Even if a threshold is used, the triggering of the safety device could be adjusted in response to the detected crash severity by changing parameters in the crash evaluation algorithm.
Although the preferred embodiment described above utilises a control unit 4 which has two processing arrangements 6 , 8 and two comparators 7 , 9 and a memory unit 10 , the invention is not limited to such an arrangement. Indeed, it is to be understood that other embodiments of the invention may have any suitable control unit which can carry out equivalent steps to the control unit 4 of the preferred embodiment, for instance with the steps being carried out by a single processor or other unit.
While the above description constitutes the preferred embodiment of the present invention, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope and fair meaning of the accompanying claims.
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A crash detection arrangement, to be installed in a motor vehicle, for detecting a crash and providing a control signal for controlling a safety device in the event that a crash is detected, the arrangement comprising an accelerometer and a control unit, the accelerometer being arranged to supply a signal to the control unit which is indicative of the acceleration of the vehicle, the control unit being adapted to: calculate a classification parameter based on the value of the signal from the accelerometer during a classification time period, which includes an interval of time before an initiation criterion was fulfilled; modify a crash evaluation algorithm in dependence upon the classification parameter; and perform the crash evaluation algorithm upon fulfillment of the initiation criterion to produce the control signal.
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FIELD OF THE INVENTION
[0001] The present invention relates to the area of novel analogues of glucose-dependent insulinotropic polypeptide, pharmaceutical compositions containing said compounds, and the use of said compounds as GIP-receptor agonists or antagonists for treatment of GIP-receptor mediated conditions, such as non-insulin dependent diabetes mellitus and obesity.
[0002] BACKGROUND ART
[0003] Glucose-dependent insulinotropic polypeptide (“GIP”, also known as “gastric inhibitory polypeptide”) is a 42-residue peptide secreted by enteroendorine K-cells of the small intestine into the bloodstream in response to oral nutrient ingestion. GIP inhibits the secretion of gastric acid, and it has been shown to be a potent stimulant for the secretion of insulin from pancreatic beta cells after oral glucose ingestion (the “incretin effect”) (Creutzfeldt, W., et al., 1979, Diabetologia, 16:75-85).
[0004] Insulin release induced by the ingestion of glucose and other nutrients is due to both hormonal and neural factors (Creutzfeldt, W., et al., 1985, Diabetologia, 28:565-573). Several gastrointestinal regulatory peptides have been proposed as incretins, and among these candidates, only GIP and glucagon-like peptide 1 (“GLP-1”) appear to fulfill the requirements to be considered physiological stimulants of postprandial insulin release (Nauck, et al., 1989, J. Clin. Endorinol. Metab., 69:654-662). It has been shown that the combined effects of GIP and GLP-1 are sufficient to explain the full incretin effect of the enteroinsular axis (Fehmann, H. C., et al., 1989, FEBS Lett., 252:109-112).
[0005] As is well known to those skilled in the art, the known and potential uses of GIP are varied and multitudinous. Thus, the administration of the compounds of this invention for purposes of eliciting an agonist effect can have the same effects and uses as GIP itself. These varied uses of GIP may be summarized as follows: treating a disease selected from the group consisting of type 1 diabetes, type 2 diabetes (Visboll, T., 2004, Dan. Med. Bull., 51:364-70), insulin resistance (WO 2005/082928), obesity (Green, B. D., et al., 2004, Current Pharmaceutical Design, 10:3651-3662), metabolic disorder (Gault, V. A., et al., 2003, Biochem. Biophys. Res. Commun., 308:207-213), central nervous system disease, neurodegenerative disease, congestive heart failure, hypoglycemia, and disorders wherein the reduction of food intake and weight loss are desired. In pancreatic islets, GIP not only enhances insulin secretion acutely, but it also stimulates insulin production through enhancement of proinsulin transcription and translation (Wang, et al., 1996, Mol. Cell. Endocrinol., 116:81-87) and enhances the growth and survival of pancreatic beta cells (Trumper, et al., 2003, Diabetes, 52:741-750). In addition to effects on the pancreas to enhance insulin secretion, GIP also has effects on insulin target tissues directly to lower plasma glucose: enhancement of glucose uptake in adipose (Eckel, et al., 1979, Diabetes, 28:1141-1142) and muscle (O'Harte, et al., 1998, J. Endocrinol., 156:237-243), and inhibition of hepatic glucose production (Elahi, D., et al., 1986, Can. J. Physiol. Pharmacol., 65:A18).
[0006] In addition, a GIP receptor antagonist in accordance with the present invention inhibits, blocks or reduces glucose absorption from the intestine of an animal. In accordance with this observation, therapeutic compositions containing GIP antagonists may be used in patients with non-insulin dependent diabetes mellitus to improve tolerance to oral glucose in mammals, such as humans, to prevent, inhibit or reduce obesity by inhibiting, blocking or reducing glucose absorption from the intestine of the mammal.
[0007] The use of unmodified GIP as a therapeutic, however, is limited by the short in vivo half-life of about 2 minutes (Said and Mutt, 1970, Science, 169:1217-1218). In serum, both incretins, GIP and GLP-1, are degraded by dipeptidyl peptidase IV (“DPPIV”). Improving the stability of GIP to proteolysis not only maintains the activity of GIP at its receptor but, more importantly, prevents the production of GIP fragments, some of which act as GIP receptor antagonists (Gault, et al., 2002, J. Endocrinol., 175:525-533). Reported modifications have included protection of the N-terminus of GIP from proteolysis by DPPIV through modification of the N-terminal tyrosine (O'Harte, et al., 2002, Diabetologia, 45:1281-1291), mutation of the alanine at position 2 (Hinke, et al., 2002, Diabetes, 51:656-661), mutation of glutamic acid at position 3 (Gault, et al., 2003, Biochem. Biophys. Res. Commun., 308:207-213), and mutation of alanine at position 13 (Gault, et al., 2003, Cell Biol. International, 27:41-46),
[0008] The following patent applications have been filed related to the effects of GIP analogues on the function of various target organs and their potential use as therapeutic agents:
[0009] PCT publication WO 00/58360 discloses peptidyl analogues of GIP which stimulate the release of insulin. In particular, this application discloses specific peptidyl analogues comprising at least 15 amino acid residues from the N-terminal end of GIP(1-42), e.g., an analogue of GIP containing exactly one amino acid substitution or modification at positions 1, 2 and 3, such as [Pro 3 ]GIP(1-42).
[0010] PCT publication WO 98/24464 discloses an antagonist of GIP consisting essentially of a 24-amino acid polypeptide corresponding to positions 7-30 of the sequence of GIP, a method of treating non-insulin dependent diabetes mellitus and a method of improving glucose tolerance in a non-insulin dependent diabetes mellitus patient.
[0011] PCT publication WO 03/082898 discloses C-terminal truncated fragments and N-terminal modified analogues of GIP, as well as various GIP analogues with a reduced peptide bond or alterations of the amino acids close to the DPPIV-specific cleavage site. This application further discloses analogues with different linkers between potential receptor binding sites of GIP. The compounds of this application are alleged to be useful in treating GIP-receptor mediated conditions, such as non-insulin dependent diabetes mellitus and obesity.
[0012] There exists a need for improved analogues of GIP, which are stable in formulation and have long plasma half-life in vivo resulting from decreased susceptibility to proteolysis and decreased clearance while maintaining binding affinity to a GIP receptor to elicit respective agonistic or antagonistic effects. Moreover, among other therapeutic effects of the compounds of the present invention as illustrated herein, tighter control of plasma glucose levels may prevent long-term diabetic complications, thereby providing an improved quality of life for patients.
SUMMARY OF THE INVENTION
[0013] In one aspect, the invention relates to peptide variants of GIP of the following formula (I):
[0000] (I) (R 2 R 3 )-A 1 -A 2 -A 3 -A 4 -A 5 -A 6 -A 7 -A 8 -A 9 -A 10 -A 11 -A 12 -A 13 - A 14 -A 15 -A 16 -A 17 -A 18 -A 19 -A 20 -A 21 -A 22 -A 23 -A 24 -A 25 -A 26 - A 27 -A 28 -A 29 -A 30 -A 31 -A 32 -A 33 -A 34 -A 35 -A 36 -A 37 -A 38 -A 39 - A 40 -A 41 -A 42 -A 43 -R 1 ,
wherein:
[0014] A 1 is deleted;
[0015] A 2 is Ala, Abu, D-Abu, Acc, Aib, β-Ala, D-ala, Gaba, Gly, 4Hppa, Ser, D-Ser, Thr, D-Thr, Val, D-Val, or deleted;
[0016] A 3 is Glu, Aib, Asp, NMe-Asp, Dhp, Dmt, NMe-Glu, 3Hyp, 4Hyp, 4Ktp, Pro, hPro, Thz, Tic, or deleted;
[0017] A 4 is Gly, Acc, Aib, β-Ala, or deleted;
[0018] A 5 is Thr, Acc, Aib, Ser, or deleted;
[0019] A 6 is Phe, Acc, Aib, Aic, Cha, 1Nal, 2Nal, 2-Pal, 3-Pal, 4-Pal, (X 4 ,X 5 ,X 6 ,X 7 ,X 8 )Phe, Trp, or deleted;
[0020] A 7 is Ile, Abu, Acc, Aib, Ala, Cha, Leu, Nle, Phe, Tle, Val, or deleted;
[0021] A 8 is Ser, Aib, Chc-Ser, Thr, or deleted;
[0022] A 9 is Asp, Aib, Glu, or deleted;
[0023] A 10 is Tyr, Acc, Cha, 1Nal, 2Nal, 2-Pal, 3-Pal, 4-Pal, Phe, (X 4 ,X 5 ,X 6 ,X 7 ,X 8 )Phe, or deleted;
[0024] A 11 is Ser, Acc, Aib, Thr, or deleted;
[0025] A 12 is Ile, Abu, Acc, Aib, Ala, Cha, Leu, Nle, Phe, Tle, Val, or deleted;
[0026] A 13 is Ala, β-Ala, D-Ala, Acc, Aib, Gly, Ser, or deleted;
[0027] A 14 is Met, Abu, Acc, Aib, Ala, Cha, Ile, Leu, Nle, Phe, Tle, or Val;
[0028] A 15 is Asp, Aib, or Glu;
[0029] A 16 is Lys, Amp, Apc, Arg, hArg, Orn, HN—CH((CH 2 ) n —N(R 4 R 8 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) t —NH—C(O)—(CH 2 ), —CH 3 ), hCys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), or Pen(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 );
[0030] A 17 is Ile, Abu, Acc, Aib, Ala, Cha, Leu, Nle, Phe, Tle, or Val;
[0031] A 18 is His, Amp, Arg, 2-Pal, 3-Pal, 4-Pal, Phe, or Tyr;
[0032] A 19 is Gln, Aib, or Asn;
[0033] A 21 is Gln, Aib, or Asn;
[0034] A 21 is Asp, Aib, or Glu;
[0035] A 22 is Phe, Acc, Aib, Aic, Cha, 1Nal, 2Nal, 2-Pal, 3-Pal, 4-Pal, (X 4 ,X 5 ,X 6 ,X 7 ,X 8 )Phe or Trp;
[0036] A 23 is Val, Abu, Acc, Aib, Ala, Cha, Ile, Leu, Nle, or Tle;
[0037] A 24 is Asn, Aib, or Gln;
[0038] A 25 is Trp, Acc, Aib, 1Nal, 2Nal, 2-Pal, 3-Pal, 4-Pal, Phe, or (X 4 ,X 5 ,X 6 ,X 7 ,X 8 )Phe;
[0039] A 26 is Leu, Acc, Aib, Cha, Ile, Nle, Phe, (X 4 ,X 5 ,X 6 ,X 7 ,X 8 )Phe, or Tle;
[0040] A 27 is Leu, Acc, Aib, Cha, Ile, Nle, Phe, (X 4 ,X 5 ,X 6 ,X 7 ,X 8 )Phe or Tle;
[0041] A 28 is Ala, Acc, or Aib;
[0042] A 29 is Gln, Aib, Asn, or deleted;
[0043] A 39 is Lys, Amp, Apc, Arg, hArg, Orn, HN—CH((CH 2 ) n —N(R 4 R 5 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) t —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) 5 —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0044] A 31 is Gly, Aib, Acc, β-Ala , 2Nal, D-2Nal, HN—CH((CH 2 ) n —N(R 4 R 5 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) y —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH 4 CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0045] A 32 is Lys, Amp, Apc, Arg, hArg, Orn, HN—CH((CH 2 ) n —N(R 4 R 5 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) x —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0046] A 33 is Lys, Amp, Apc, Arg, hArg, Orn, Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0047] A 34 is Asn, Aib, Gln, Ser, HN—CH((CH 2 ) n —N(R 4 R 5 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) x —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0048] A 35 is Asp, Aib, Glu, HN—CH((CH 2 ) n —N(R 4 R 5 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0049] A 36 is Trp, Acc, Aib, 1Nal, 2Nal, 2-Pal, 3-Pal, 4-Pal, Phe, (X 4 ,X 5 ,X 6 ,X 7 ,X 8 )Phe, HN—CH((CH 2 ) n —N(R 4 R 8 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0050] A 37 is Lys, Amp, Apc, Arg, hArg, Orn, HN—CH((CH 2 ) n —N(R 4 R 8 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) x —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) x —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) x —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0051] A 38 is His, Amp, Phe, 2-Pal, 3-Pal, 4-Pal, Tyr, HN—CH((CH 2 ) n —N(R 4 R 5 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) r CH 3 ), hCys(succinimide-N—(CH 2 ) x —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) x —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0052] A 39 is Asn, Aib, Gln, HN—CH((CH 2 ) n —N(R 4 R 5 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) x —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0053] A 40 is Ile, Acc, Aib, Ser, Thr, HN—CH((CH 2 ) n —N(R 4 R 5 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0054] A 41 is Thr, Acc, Aib, Asn, Gln, HN—CH((CH 2 ) n —N(R 4 R 5 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) x —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) x —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) t —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0055] A 42 is Gln, Aib, Acc, Asn, HN—CH((CH 2 ) n —N(R 4 R 5 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) x —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) x —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0056] A 43 is Acc, Aib, Ala, Asp, Gln, Phe, Thr, Trp, HN—CH((CH 2 ) n —N(R 4 R 6 ))—C(O), Cys(succinimide-N-alkyl), hCys(succinimide-N-alkyl), Pen(succinimide-N-alkyl), Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 ), Cys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), hCys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), Pen(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 ), or deleted;
[0057] R 1 is OH, NH 2 , (C 1 -C 30 )alkoxy, or NH—X 2 —CH 2 —Z 0 , wherein X 2 is a (C 0 -C 30 )hydrocarbon moiety, and Z 0 is H, OH, CO 2 H or CONH 2 ;
[0058] each of R 2 , R 3 , R 4 and R 5 is independently selected from the group consisting of H, (C 1 -C 30 )alkyl, (C 1 -C 30 )heteroalkyl, (C 1 -C 30 )acyl, (C 2 -C 30 )alkenyl, (C 2 -C 30 )alkynyl, aryl(C 1 -C 30 )alkyl, aryl(C 1 -C 30 )acyl, substituted (C 1 -C 30 )alkyl, substituted (C I -C 30 )heteroalkyl, substituted (C 1 -C 30 )acyl, substituted (C 2 -C 30 )alkenyl, substituted (C 2 -C 30 )alkynyl, substituted aryl(C 1 -C 30 )alkyl, and substituted aryl(C 1 -C 30 )acyl; provided that when R 2 is (C 1 -C 30 )acyl, aryl(C 1 -C 30 )acyl, substituted (C 1 -C 30 )acyl, or substituted aryl(C 1 -C 30 )acyl, then R 3 is H, (C 1 -C 30 )alkyl, (C 1 -C 30 )heteroalkyl, (C 2 -C 30 )alkenyl, (C 2 -C 30 )alkynyl, aryl(C 1 -C 30 )alkyl, substituted (C 1 -C 30 )alkyl, substituted (C 1 -C 30 )heteroalkyl, substituted (C 2 -C 30 )alkenyl, substituted (C 2 -C 30 )alkynyl, or substituted aryl(C 1 -C 30 )alkyl; further provided that when R 4 is (C 1 -C 30 )acyl, aryl(C 1 -C 30 )acyl, substituted (C 1 -C 30 )acyl, or substituted aryl(C 1 -C 30 )acyl, then R 5 is H, (C 1 -C 30 )alkyl, (C 1 -C 30 )heteroalkyl, (C 2 -C 30 )alkenyl, (C 2 -C 30 )alkynyl, aryl(C 1 -C 30 )alkyl, substituted (C 1 -C 30 )alkyl, substituted (C 1 -C 30 )heteroalkyl, substituted (C 2 -C 30 )alkenyl, substituted (C 2 -C 30 )alkynyl, or substituted aryl(C 1 -C 30 )alkyl;
[0059] n is, independently for each occurrence, an integer from 1 to 5 inclusive;
[0060] s, t, x and y each is, independently for each occurrence, an integer from 1 to 30 inclusive;
[0061] X 4 , X 5 , X 6 , X 7 and X 8 each is, independently for each occurrence, H, F, Cl, Br, I, (C 1-10 )alkyl, substituted (C 1-10 )alkyl, aryl, substituted aryl, OH, NH 2 , NO 2 , or CN; and
[0062] provided that when A 2 is 4Hppa, then R 2 and R 3 are deleted.
[0063] A subset (A) of the compounds covered by the above formula (I) are those in which:
[0064] A 2 is Ala, 4Hppa, or deleted;
[0065] A 3 is Glu, 4Hyp, Pro, or deleted;
[0066] A 4 is Gly or deleted;
[0067] A 5 is Thr or deleted;
[0068] A 6 is Phe or deleted;
[0069] A 7 is Ile, A5c, A6c, or deleted;
[0070] A 8 is Ser, Chc-Ser, or deleted;
[0071] A 9 is Asp or deleted;
[0072] A 10 is Tyr or deleted;
[0073] A 11 is Ser, A6c, Aib, or deleted;
[0074] A 12 is Ile or deleted;
[0075] A 13 is Ala, Aib, or deleted;
[0076] A 14 is Met, A6c, or Nle;
[0077] A 15 is Asp;
[0078] A 16 is Lys;
[0079] A 17 is Ile;
[0080] A 18 is His;
[0081] A 19 is Gln;
[0082] A 20 is Gln;
[0083] A 21 is Asp;
[0084] A 22 is Phe;
[0085] A 23 is Val;
[0086] A 24 is Asn;
[0087] A 25 is Trp;
[0088] A 26 is Leu;
[0089] A 27 is Leu;
[0090] A 28 is Ala;
[0091] A 29 is Gln;
[0092] A 30 is Lys;
[0093] A 31 is Gly, Cys(Hsu), Cys(Psu), 2Nal, D-2Nal, Orn(N—C(O)—(CH 2 ) 4 —CH 3 ), Orn(N—C(O)—(CH 2 ) 8 —CH 3 ), Orn(N—C(O)—(CH 2 ) 12 —CH 3 ), or deleted;
[0094] A 32 is Lys, Cys(Psu), or deleted;
[0095] A 33 is Lys, Cys(Psu), or deleted;
[0096] A 34 is Asn, Cys(Psu), Orn(N—C(O)—(CH 2 ) 8 —CH 3 ), or deleted;
[0097] A 35 is Asp, Cys(Psu), or deleted;
[0098] A 36 is Trp, Cys(Psu), or deleted;
[0099] A 37 is Lys, Cys(Psu), or deleted;
[0100] A 38 is His, Cys(Psu), or deleted;
[0101] A 39 is Asn, Cys(Psu), or deleted;
[0102] A 40 is Ile, Cys(Psu), or deleted;
[0103] A 41 is Thr or deleted;
[0104] A 42 is Gln or deleted;
[0105] A 43 is Gln or deleted; and
[0106] provided that at least one of A 2 , A 3 , A 4 , A 5 , A 6 , A 7 , A 8 , A 9 , A 11 , A 13 , A 14 , A 31 , A 32 , A 33 , A 34 , A 35 , A 36 , A 37 , A 38 , A 39 and A 40 is not the amino acid residue of the corresponding position of the native GIP.
[0107] A subset of the compounds of the preceding subset (A) are those in which:
[0108] A 2 is deleted;
[0109] A 3 is deleted;
[0110] A 4 is deleted;
[0111] A 5 is deleted;
[0112] A 6 is deleted;
[0113] A 7 is A5c or A6c;
[0114] A 8 is Ser;
[0115] A 9 is Asp;
[0116] A 10 is Tyr;
[0117] A 11 is Ser;
[0118] A 12 is He;
[0119] A 13 is Ala;
[0120] A 14 is Met;
[0121] A 31 is Gly, Cys(Hsu), Cys(Psu), 2Nal, D-2Nal, Orn(N—C(O)—(CH 2 ) 4 —CH 3 ), Orn(N—C(O)—(CH 2 ) 8 —CH 3 ), or Orn(N—C(O)—(CH 2 ) 12 —CH 3 );
[0122] A 32 is Lys or Cys(Psu);
[0123] A 33 is Lys or Cys(Psu);
[0124] A 34 is Asn, Cys(Psu), or Orn(N—C(O)—(CH 2 ) 8 —CH 3 );
[0125] A 35 is Asp or Cys(Psu);
[0126] A 36 is Trp or Cys(Psu);
[0127] A 37 is Lys or Cys(Psu);
[0128] A 38 is His or Cys(Psu);
[0129] A 39 is Asn or Cys(Psu);
[0130] A 40 is Ile or Cys(Psu);
[0131] A 41 is Thr;
[0132] A 42 is Gln; and
[0133] A 43 is deleted.
[0134] A subset of the compounds of the preceding subset (A) are those in which A 43 is deleted, A 2 is 4Hppa, and at least one of A 3 , A 7 , A 11 , A 13 and A 14 is not the amino acid residue of the corresponding position of the native GIP.
[0135] Another subset of the compounds of the preceding subset (A) are those in which A 2 to A 5 and A 31 to A 43 are deleted, and at least one of A 6 , A 7 , A 11 and A 14 is not the amino acid residue of the corresponding position of the native GIP.
[0136] Another subset of the compounds of the preceding subset (A) are those in which A 2 to A 7 and A 43 are deleted, and at least one of A 8 and A 31 is not the amino acid residue of the corresponding position of the native GIP.
[0137] Another subset of the compounds of the preceding subset (A) are those in which A 2 to A 5 and A 43 are deleted, and at least one of A 6 , A 7 and A 31 is not the amino acid residue of the corresponding position of the native GIP.
[0138] Another subset of the compounds of the preceding subset (A) are those in which A 2 to A 5 and A 32 to A 43 are deleted, and at least one of A 6 , A 7 and A 31 is not the amino acid residue of the corresponding position of the native GIP.
[0139] Preferred compounds of formula (I) are:
[0000]
Example 1:
(SEQ ID NO: 4)
(Ac-A6c 7 )hGIP(7-42)-OH;
Example 2:
(SEQ ID NO: 5)
[Ac-A6c 7 , Cys(Psu) 40 ]hGIP(7-42)-OH;
Example 3:
(SEQ ID NO: 6)
[Ac-A6c 7 , Cys(Psu) 39 ]hGIP(7-42)-OH;
Example 4:
(SEQ ID NO: 7)
[Ac-A6c 7 , Cys(Psu) 38 ]hGIP(7-42)-OH;
Example 5:
(SEQ ID NO: 8)
[Ac-A6c 7 , Cys(Psu) 36 ]hGIP(7-42)-OH;
Example 6:
(SEQ ID NO: 9)
[Ac-A6c 7 , Cys(Psu) 35 ]hGIP(7-42)-OH;
Example 7:
(SEQ ID NO: 10)
[Ac-A6c 7 , Cys(Psu) 34 ]hGIP(7-42)-OH;
Example 8:
(SEQ ID NO: 11)
[Ac-A6c 7 , Cys(Psu) 33 ]hGIP(7-42)-OH;
Example 9:
(SEQ ID NO: 12)
[Ac-A6c 7 , Cys(Psu) 32 ]hGIP(7-42)-OH;
Example 10:
(SEQ ID NO: 13)
[Ac-A6c 7 , Cys(Psu) 31 ]hGIP(7-42)-OH;
Example 11:
(SEQ ID NO: 14)
[Ac-A6c 7 , Cys(Psu) 37 ]hGIP(7-42)-OH;
Example 12:
(SEQ ID NO: 15)
[Ac-A6c 7 , Orn 31 (N-C(O)-(CH 2 ) 12 -CH 3 )]hGIP(7-42)-OH;
Example 13:
(SEQ ID NO: 16)
[Ac-A6c 7 , Orn 31 (N-C(O)-(CH 2 ) 8 -CH 3 )]hGIP(7-42)-OH;
Example 14:
(SEQ ID NO: 17)
[A6c7, Orn 31 (N-C(O)-(CH 2 ) 8 -CH 3 )]hGIP(7-42)-OH;
Example 15:
(SEQ ID NO: 18)
[CH 3 -(CH 2 ) 8 -C(O)-A6c 7 ,
Orn 31 (N-C(O)-(CH 2 ) 8 -CH 3 )]hGIP(7-42)-OH;
Example 16:
(SEQ ID NO: 19)
[Ac-A6c 7 , Orn 31 (N-C(O)-(CH 2 ) 4 -CH 3 )]hGIP(7-42)-OH;
Example 17:
(SEQ ID NO: 20)
[A6c 7 , Orn 31 (N-C(O)-(CH 2 ) 4 -CH 3 )]hGIP(7-42)-OH;
Example 18:
(SEQ ID NO: 21)
[CH 3 -(CH 2 ) 4 -C(O)-A6c 7 ,
Orn 31 (N-C(O)-(CH 2 ) 4 -CH 3 )]hGIP(7-42)-OH;
Example 19:
(SEQ ID NO: 22)
[Ac-A6c 7 , Orn 34 (N-C(O)-(CH 2 ) 8 -CH 3 )]hGIP(7-42)-OH;
Example 20:
(SEQ ID NO: 23)
[A6c 7 , Orn 34 (N-C(O)-(CH 2 ) 8 -CH 3 )]hGIP(7-42)-OH;
Example 21:
(SEQ ID NO: 24)
[CH 3 -(CH 2 ) 8 -C(O)-A6c 7 ,
Orn 34 (N-C(O)-(CH 2 ) 8 -CH 3 )]hGIP(7-42)-OH;
Example 22:
(SEQ ID NO: 25)
[Ac-A6c 7 , Cys(Hsu) 31 ]hGIP(7-42)-OH;
Example 23:
(SEQ ID NO: 26)
[A6c 7 , Cys(Hsu) 31 ]hGIP(7-42)-OH;
Example 24:
(SEQ ID NO: 27)
(Ac-A6c 7 , 2Nal 31 )hGIP(7-42)-OH;
Example 25:
(Ac-A6c 7 , D-2Nal 31 )hGIP(7-42)-OH;
Example 26:
(SEQ ID NO: 28)
(Ac-4Hyp 3 , A6c 7 )hGIP(3-42)-OH;
Example 27:
(SEQ ID NO: 29)
(Ac-A6c 7 , Gln 43 )hGIP(7-43)-OH;
Example 28:
(SEQ ID NO: 30)
(Ac-A6c 7 , Cys(Psu) 31 ]hGIP(7-34)-NH 2 ;
Example 29:
(SEQ ID NO: 31)
[Ac-A6c 7 , Cys(Psu) 31 ]hGIP(7-31)-NH 2 ;
Example 30:
(SEQ ID NO: 32)
[Ac-Phe 6 , A6c 7 , Cys(Psu) 31 ]hGIP(6-42)-OH;
Example 31:
(SEQ ID NO: 33)
[A6c 7 , Cys(Psu) 31 ]hGIP(6-42)-OH;
Example 32:
(SEQ ID NO: 34)
(Ac-Phe 6 , A6c 7 )hGIP(6-30)-NH 2 ;
Example 33:
(SEQ ID NO: 35)
[Ac-Phe 6 , A6c 7 , Cys(Psu) 31 ]hGIP(6-31)-NH 2 ;
Example 34:
(SEQ ID NO: 36)
[A6c 7 , Cys(Psu) 31 ]hGIP(6-31)-NH 2 ;
Example 35:
(SEQ ID NO: 37)
(A5c 7 , Nle 14 )hGIP(6-30)-NH 2 ;
Example 36:
(SEQ ID NO: 38)
(A6c 7 , Nle 14 )hGIP(6-30)-NH 2 ;
Example 37:
(SEQ ID NO: 39)
(Aib 11 , Nle 14 )hGIP(6-30)-NH 2 ;
Example 38:
(SEQ ID NO: 40)
[Ac-Asp 9 , Cys(Psu) 33 ]hGIP(9-42)-OH;
Example 39:
(SEQ ID NO: 41)
[Orn 31 (N-C(O)-(CH 2 ) 8 -CH 3 )]hGIP(8-42)-OH;
Example 40:
(SEQ ID NO: 42)
[Chc-Ser 8 , Cys(Psu) 31 ]hGIP(8-42)-OH;
Example 41:
(SEQ ID NO: 43)
[CH 3 -(CH 2 ) 4 -C(O)-Ser 8 , Cys(Psu) 31 ]hGIP(8-42)-OH;
Example 42:
(SEQ ID NO: 44)
(4Hppa 2 , 4Hyp 3 , A6c 7 )hGIP(2-42)-OH;
Example 43:
(SEQ ID NO: 45)
(4Hppa 2 , Pro 3 , Nle 14 )hGIP(2-42)-OH;
Example 44:
(SEQ ID NO: 46)
(4Hppa 2 , Aib 13 )hGIP(2-42)-OH);
Example 45:
(SEQ ID NO: 47)
(4Hppa 2 , A6c 14 )hGIP(2-42)-OH;
Example 46:
(SEQ ID NO: 48)
(4Hppa 2 , A6c 11 )hGIP(2-42)-OH;
and
Example 47:
(SEQ ID NO: 49)
[Aib 2 , A5c 11 , Nle 14 ,
Lys 43 (N-C(O)-(CH 2 ) 10 -CH 3 )]hGIP(2-43)-OH.
[0140] According to another aspect of the present invention, a compound according to the present invention as summarized hereinabove and claimed in the appended claims may further comprise a covalently linked PEG moiety, in which said PEG moiety is covalently linked to the compound via a Cys(maleimide), hCys(maleimide), or Pen(maleimide) linker, to form Cys(succinimide-N-PEG), hCys(succinimide-N-PEG), or Pen(succinimide-N-PEG), wherein “succinimide-N-PEG” is either linear or branched as defined hereinbelow. Such PEG moiety has average molecular weight of from about 2,000 to about 80,000, and preferably such PEG moiety is selected from the group consisting of 5K PEG, 10K PEG, 20K PEG, 30K PEG, 40K PEG, 50K PEG, and 60K PEG, to form Cys(succinimide-N-5K PEG), Cys(succinimide-N-10K PEG), Cys(succinimide-N-20K PEG), Cys(succinimide-N-30K PEG), Cys(succinimide-N-40K PEG), Cys(succinimide-N-50K PEG), Cys(succinimide-N-60K PEG), hCys(succinimide-N-5K PEG), hCys(succinimide-N-10K PEG), hCys(succinimide-N-20K PEG), hCys(succinimide-N-30K PEG), hCys(succinimide-N-40K PEG), hCys(succinimide-N-50K PEG), hCys(succinimide-N-60K PEG), Pen(succinimide-N-5K PEG), Pen(succinimide-N-10K PEG), Pen(succinimide-N-20K PEG), Pen(succinimide-N-30K PEG), Pen(succinimide-N-40K PEG), Pen(succinimide-N-50K PEG), or Pen(succinimide-N-60K PEG).
[0141] PEGylation occurs at any one of amino acid residue positions 16, 30, and 31-43, and preferably at any one of amino acid residue positions 32, 33 and 43, whereby Cys(succinimide-N-PEG), hCys(succinimide-N-PEG), or Pen(succinimide-N-PEG) is placed in any one of such amino acid residue positions.
[0142] Further, the above formula (I) may be expanded to provide PEGylation sites at positions A 44 -A 47 . The C-terminus of such PEGylated compounds of the present invention may be amidated, e.g., (Ac-A6c 7 )hGIP(7-42)-NH 2 (SEQ ID NO:50), or it may remain as free acid, e.g., (Ac-A6c 7 )hGEP(7-42)-OH (SEQ ID NO:4).
DETAILED DESCRIPTION OF THE INVENTION
[0143] The application employs the following commonly understood abbreviations:
[0144] Abu: α-aminobutyric acid
[0145] Acc: 1-amino-1 -cyclo(C 3 -C 9 )alkyl carboxylic acid
A3c: 1-amino-1-cyclopropanecarboxylic acid A4c: 1-amino-1-cyclobutanecarboxylic acid A5c: 1-amino-1-cyclopentanecarboxylic acid A6c: 1-amino-1 -cyclohexanecarboxylic acid
[0150] Act: 4-amino-4-carboxytetrahydropyran
[0151] Ado: 12-aminododecanoic acid
[0152] Aib: α-aminoisobutyric acid
[0153] Aic: 2-aminoindan-2-carboxylic acid
[0154] Ala or A: alanine
[0155] β-Ala: beta-alanine
[0156] Amp: 4-amino-phenylalanine;
[0157] Apc: 4-amino-4-carboxypiperidine:
[0158] Arg or R: arginine
[0159] hArg: homoarginine
[0160] Asn or N: asparagine
[0161] Asp or D: aspartic acid
[0162] Aun: 11-aminoundecanoic acid
[0163] Ava: 5-aminovaleric acid
[0164] Cha: β-cyclohexylalanine
[0165] Chc: cyclohexyl carboxylic acid
[0166] Cys or C: cysteine
[0167] D-Ala: D-alanine
[0168] Dhp: 3,4-dehydroproline
[0169] Dmt: 5,5-dimethylthiazolidine-4-carboxylic acid
[0170] Gaba: γ-aminobutyric acid
[0171] Gln or Q: glutamine
[0172] Glu or E: glutamic acid
[0173] Gly or G: glycine
[0174] His or H: histidine
[0175] 4Hppa: 3-(4-hydroxyphenyl)propionic acid
[0176] Hsu: N-hexylsuccinimide
[0177] 3Hyp: 3-hydroxyproline
[0178] 4Hyp: 4-hydroxyproline
[0179] hPro: homoproline
[0180] Ile or I: isoleucine
[0181] 4Ktp: 4-ketoproline
[0182] Leu or L: leucine
[0183] Lys or K: lysine
[0184] Met or M: methionine
[0185] Nle: norleucine
[0186] NMe-Tyr: N-methyl-tyrosine
[0187] 1Nal or 1-Nal: β-(1-naphthyl)alanine
[0188] 2Nal or 2-Nal: β-(2-naphthypalanine
[0189] Nle: norleucine
[0190] Nva: norvaline
[0191] Orn: ornithine
[0192] 2Pal or 2-Pal: β-(2-pyridinypalanine
[0193] 3Pal or 3-Pal: β-(3-pyridinypalanine
[0194] 4Pal or 4-Pal: β-(4-pyridinypalanine
[0195] Pen: penicillamine
[0196] Phe or F: phenylalanine
[0197] (3,4,5F)Phe: 3,4,5-trifluorophenylalanine
[0198] (2,3,4,5,6)Phe: 2,3,4,5,6-pentafluorophenylalanine
[0199] Pro or P: proline
[0200] Psu: N-propylsuccinimide
[0201] Ser or S: serine
[0202] Taz: β-(4-thiazolypalanine
[0203] 3Thi: β-(3-thienypalanine
[0204] Thr or T: threonine
[0205] Thz: thioproline
[0206] Tic: tetrahydroisoquinoline-3-carboxylic acid
[0207] Tle: tert-leucine
[0208] Trp or W: tryptophan
[0209] Tyr or Y: tyrosine
[0210] Val or V: valine
[0000] Certain other abbreviations used herein are defined as follows:
[0211] Act: acetonitrile
[0212] Boc: tert-butyloxycarbonyl
[0213] BSA: bovine serum albumin
[0214] DCM: dichloromethane
[0215] DIPEA: diisopropylethyl amine
[0216] DMF: dimethylformamide
[0217] DTT: dithiothrieitol
[0218] ESI: electrospray ionization
[0219] Fmoc: 9-fluorenylmethyloxycarbonyl
[0220] HBTU: 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate
[0221] HOBT: 1-hydroxybenzotriazole
[0222] HPLC: high performance liquid chromatography
[0223] IBMX: isobutylmethylxanthine
[0224] LC-MS: liquid chromatography-mass spectrometry
[0225] Mtt: methyltrityl
[0226] NMP: N-methylpyrrolidone
[0227] 5K PEG: polyethylene glycol, which may include other functional groups or moieties such as a linker, and which is either linear or branched as defined hereinbelow, with an average total molecular weight of about 5,000
[0228] 10K PEG: polyethylene glycol, which may include other functional groups or moieties such as a linker, and which is either linear or branched as defined hereinbelow, with an average total molecular weight of about 10,000
[0229] 20K PEG: polyethylene glycol, which may include other functional groups or moieties such as a linker, and which is either linear or branched as defined hereinbelow, with an average total molecular weight of about 20,000
[0230] 30K PEG: polyethylene glycol, and which is either linear or branched as defined hereinbelow, which may include other functional groups or moieties such as a linker, with an average total molecular weight of about 30,000
[0231] 40K PEG: polyethylene glycol, which may include other functional groups or moieties such as a linker, and which is either linear or branched as defined hereinbelow, with an average total molecular weight of about 40,000
[0232] 50K PEG: polyethylene glycol, which may include other functional groups or moieties such as a linker, and which is either linear or branched as defined hereinbelow, with an average total molecular weight of about 50,000
[0233] 60K PEG: polyethylene glycol, which may include other functional groups or moieties such as a linker, and which is either linear or branched as defined hereinbelow, with an average total molecular weight of about 60,000
[0234] tBu: tert-butyl
[0235] TIS: triisopropylsilane
[0236] Trt: trityl
[0237] TFA: trifluoro acetic acid
[0238] Z: benzyloxycarbonyl
[0239] “Cys(succinimide-N-alkyl)” has the structure of:
[0000]
[0240] “Cys(Hsu)” has the structure of:
[0000]
[0241] “Cys(Psu)” has the structure of:
[0000]
[0242] “Orn(N—C(O)—(CH 2 ) 12 —CH 3 )” has the structure of:
[0000]
[0243] “Cys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 )” has the structure of:
[0000]
[0000] wherein, x=1-30, and y=1-30.
[0244] “hCys(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 )” has the structure of:
[0000]
[0000] wherein, x=1-30, and y=1-30.
[0245] “Pen(succinimide-N—(CH 2 ) x —C(O)—NH—(CH 2 ) y —CH 3 )” has the structure of:
[0000]
[0000] wherein, x=1-30, and y=1-30.
[0246] “Cys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 )” has the structure of:
[0000]
[0000] wherein, s=1-30, and t=1-30.
[0247] “hCys(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 )” has the structure of:
[0000]
[0000] wherein s=1-30, and t=1-30.
[0248] “Pen(succinimide-N—(CH 2 ) s —NH—C(O)—(CH 2 ) t —CH 3 )” has the structure of:
[0000]
[0000] wherein s=1-30, and t=1-30.
[0000]
[0249] “Cys(succinimide-N-PEG)” has the structure of:
[0000]
[0250] “hCys(succinimide-N-PEG)” has the structure of:
[0000]
[0251] “Pen(succinimide-N-PEG)” has the structure of:
[0252] “Cys(succinimide-N—(CH 2 ) 2 —C(O)NH—(CH 2 ) 3 -PEG)” has the structure of:
[0000]
[0253] “Cys(succinimide-N—(CH 2 ) 2 —C(O)NH—(CH 2 ) 3 —O—CH 2 —CH(PEG)-CH 2 -PEG)” has the structure of:
[0000]
[0254] With the exception of the N-terminal amino acid, all abbreviations (e.g., Ala) of amino acids in this disclosure stand for the structure of —NH—C(R)(R′)—OO—, wherein R and R′ each is, independently, hydrogen or the side chain of an amino acid (e.g., R═CH 3 and R′=H for Ala), or R and R′ may be joined to form a ring system. For the N-terminal amino acid, the abbreviation stands for the structure of (R 2 R 3 )N—C(R)(R′)—CO—, wherein R 2 and R 3 are as defined in the above formula (I).
[0255] The term “(C 1 -C 30 )hydrocarbon moiety” encompasses alkyl, alkenyl and alkynyl, and in the case of alkenyl and alkynyl there are C 2 -C 30 .
[0256] A peptide of this invention is also denoted herein by another format, e.g., (A5c 2 )hGIP(1-42)-OH (SEQ ID NO:3), with the substituted amino acids from the natural sequence placed between the brackets (e.g., A5c 2 for Ala 2 in hGIP). The numbers between the parentheses refer to the number of amino acids present in the peptide (e.g., hGIP(1-42)-OH (SEQ ID NO:1) is amino acids 1 through 42 of the peptide sequence for hGIP). The designation “NH 2 ” in hGIP(1-30)-NH 2 (SEQ ID NO:2) indicates that the C-terminus of the peptide is amidated; hGIP(1-42) (SEQ ID NO:1) or hGIP(1-42)-OH (SEQ ID NO:1) means that the C-terminus is the free acid.
[0257] Human GIP (“hGIP”) has the amino acid sequence of:
[0000]
(SEQ ID NO: 1)
Tyr-Ala-Glu-Gly-Thr-Phe-Ile-Ser-Asp-Tyr-Ser-
1 5 10
Ile-Ala-Met-Asp-Lys-Ile-His-Gln-Gln-Asp-Phe-
15 20
Val-Asn-Trp-Leu-Leu-Ala-Gln-Lys-Gly-Lys-Lys-
25 30
Asn-Asp-Trp-Lys-His-Asn-Ile-Thr-Gln.
35 40
[0258] “Acyl” refers to R″-C(O)—, where R″ is H, alkyl, substituted alkyl, heteroalkyl, substituted heteroalkyl, alkenyl, substituted alkenyl, aryl, alkylaryl, or substituted alkylaryl.
[0259] “Alkyl” refers to a hydrocarbon group containing one or more carbon atoms, where multiple carbon atoms if present are joined by single bonds. The alkyl hydrocarbon group may be straight-chain or contain one or more branches or cyclic groups.
[0260] “Substituted alkyl” refers to an alkyl wherein one or more hydrogen atoms of the hydrocarbon group are replaced with one or more substituents selected from the group consisting of halogen, (i.e., fluorine, chlorine, bromine, and iodine), —OH, —CN, —SH, —NH 2 , —NHCH 3 , —NO 2 , —C 1-20 alkyl substituted with halogens, —CF 3 , —OCH 3 , —OCF 3 , and —(CH 2 ) 0-20 —COOH. In different embodiments 1, 2, 3 or 4 substituents are present. The presence of —(CH 2 ) 0-20 —COOH results in the production of an alkyl acid. Examples of alkyl acids containing, or consisting of, —(CH 2 ) 0-20 —COOH include 2-norbornane acetic acid, tert-butyric acid and 3-cyclopentyl propionic acid.
[0261] “Heteroalkyl” refers to an alkyl wherein one of more of the carbon atoms in the hydrocarbon group are replaced with one or more of the following groups: amino, amido, —O—, —S— or carbonyl. In different embodiments 1 or 2 heteroatoms are present.
[0262] “Substituted heteroalkyl” refers to a heteroalkyl wherein one or more hydrogen atoms of the hydrocarbon group are replaced with one or more substituents selected from the group consisting of halogen, —OH, —CN, —SH, —NH 2 , —NHCH 3 , —NO 2 , —C 1-20 alkyl substituted with halogens, —CF 3 , —OCH 3 , —OCF 3 , and —(CH 2 ) 0-20 —COOH. In different embodiments 1, 2, 3 or 4 substituents are present.
[0263] “Alkenyl” refers to a hydrocarbon group made up of two or more carbons wherein one or more carbon-carbon double bonds are present. The alkenyl hydrocarbon group may be straight-chain or contain one or more branches or cyclic groups.
[0264] “Substituted alkenyl” refers to an alkenyl wherein one or more hydrogens are replaced with one or more substituents selected from the group consisting of halogen, —OH, —CN, —SH, —NH 2 , —NHCH 3 , —NO 2 , —C 1-20 alkyl substituted with halogens, —CF 3 , —OCH 3 , —OCF 3 , and —(CH 2 ) 0-20 —COOH. In different embodiments 1, 2, 3 or 4 substituents are present.
[0265] “Aryl” refers to an optionally substituted aromatic group with at least one ring having a conjugated pi-electron system, containing up to three conjugated or fused ring systems. Aryl includes carbocyclic aryl, heterocyclic aryl and biaryl groups. Preferably, the aryl is a 5 or 6 membered ring. Preferred atoms for a heterocyclic aryl are one or more sulfur, oxygen, and/or nitrogen. Examples of aryl include phenyl, 1-naphthyl, 2-naphthyl, indole, quinoline, 2-imidazole, and 9-anthracene. Aryl substituents are selected from the group consisting of —C 1-20 alkyl, —C 1-20 alkoxy, halogen, —OH, —CN, —SH, —NH 2 , —NO 2 , —C 1-20 alkyl substituted with halogens, —CF 3 , —OCF 3 , and —(CH 2 ) 0-20 —COOH. In different embodiments the aryl contains 0, 1, 2, 3, or 4 substituents.
[0266] “Alkylaryl” refers to an “alkyl” joined to an “aryl”.
Synthesis
[0267] The peptides of this invention can be prepared by standard solid phase peptide synthesis. See, e.g., Stewart, J. M., et al., 1984, Solid Phase Synthesis, Pierce Chemical Co., 2d ed. If R 1 is NH—X 2 —CH 2 —CONH 2 , i.e., Z 0 ═CONH 2 , the synthesis of the peptide starts with Fmoc-HN—X 2 —CH 2 —CONH 2 which is coupled to Rink amide MBHA resin. If R 1 is NH—X 2 —CH 2 —COOH, i.e., Z 0 ═COOH, the synthesis of the peptide starts with Fmoc-HN—X 2 —CH 2 —COOH which is coupled to Wang resin. For this particular step, 2 molar equivalents of Fmoc-HN—X 2 —COOH, HBTU and HOBt and 10 molar equivalents of DIPEA are used. The coupling time is about 8 hours.
[0268] In the synthesis of a GIP analogue of this invention containing A5c, A6c, and/or Aib, the coupling time is 2 hrs for these residues and the residue immediately following them.
[0269] The substituents R 2 and R 3 of the above generic formula can be attached to the free amine of the N-terminal amino acid A 1 by standard methods known in the art. For example, alkyl groups, e.g., (C 1 —C 30 )alkyl, can be attached using reductive alkylation. Hydroxyalkyl groups, e.g., (C 1 -C 30 )hydroxyalkyl, can also be attached using reductive alkylation wherein the free hydroxy group is protected with a tert-butyl ester. Acyl groups, e.g., —C(O)X 3 , can be attached by coupling the free acid, e.g., —X 3 COOH, to the free amine of the N-terminal amino acid by mixing the completed resin with 3 molar equivalents of both the free acid and diisopropylcarbodiimide in methylene chloride for about one hour. If the free acid contains a free hydroxy group, e.g., 3-fluoro-4-hydroxyphenylacetic acid, then the coupling should be performed with an additional 3 molar equivalents of HOBT.
[0270] The following examples describe synthetic methods for making a peptide of this invention, which methods are well-known to those skilled in the art. Other methods are also known to those skilled in the art. The examples are provided for the purpose of illustration and are not meant to limit the scope of the present invention in any manner.
EXAMPLE 2
[Ac-A6c 7 , Cys(Psu) 40 ]hGIP(7-42)-OH
[0271] Solid-phase peptide synthesis was used to assemble the peptide using microwave-assisted Fmoc Chemistry on a Liberty Peptide Synthesizer (CEM; Matthews, N.C., USA) at the 0.1 mmole scale. Pre-loaded Fmoc-Gln(Trt)-Wang resin (0.59 mmole/g; Novabiochem, San Diego, Calif., USA) was used to generate the C-terminal acid peptide. The resin (0.17 g) was placed in a 50 ml conical tube along with 15 ml of dimethylformamide (DMF) and loaded onto a resin position on the synthesizer. The resin was then quantitatively transferred to the reaction vessel via the automated process. The standard Liberty synthesis protocol for 0.1 mmole scale synthesis was used. This protocol involves deprotecting the N-terminal Fmoc moiety via an initial treatment with 7 ml of 20% piperidine, containing 0.1M N-hydroxybenzotriazole (HOBT), in DMF. The initial deprotection step was for 30 seconds with microwave power (45 watts, maximum temperature of 75° C.), and nitrogen bubbling (3 seconds on/7 seconds off). The reaction vessel was then drained and a second piperidine treatment, identical to the first treatment, except that it was for a 3-minute duration. The resin was then drained and thoroughly washed with DMF several times. The protected amino acid, Fmoc-Thr(tBu)-OH, prepared as 0.2M stock solution in DMF, was then added (2.5 ml, 5 equivalents), followed by 1.0 ml of 0.45M (4.5 eq.) HBTU [2-(1H-benzo-triazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosaphate] in DMF. This was followed by the addition of 0.5 ml of 2M (10 eq.) DIPEA (diisopropylethylamine) in NMP (N-methylpyrrollidinone). The coupling step was performed for 5 minutes using 20 watts of microwave power, a max temperature of 75 ° C., and the same rate of nitrogen bubbling.
[0272] Following the initial coupling step, the reaction vessel was drained to waste and the coupling step repeated. Cycle 2 was then initiated similar to cycle 1. All amino acids were introduced similarly and a double-coupling strategy was employed throughout the entire sequence. Cycles 1-3, 19-20, 25-26, and 30-34 contained a capping procedure immediately following the coupling step. Capping was performed by adding 7 ml of 0.5M acetic anhydride, containing 0.015M HOBT in NMP, along with 2 ml of the 2M DIPEA solution using a multi-step microwave protocol: 50 watts of power for 30 seconds (65° C. max temperature), followed by 30 seconds of microwave power off, followed by a second round of 30 seconds of microwave power on (50 watts), and then again 30 seconds of no microwave power. The resin was then drained and thoroughly washed with DMF. The following amino acids (Advanced Chemtech; Louisville, Ky., USA) were used: Cycle 1: Fmoc-Thr(OtBu)-OH; Cycle 2: Fmoc-Cys(Trt)-OH; Cycle 3: Fmoc-Asn(Trt)-OH; Cycle 4: Fmoc-His(Trt)-OH; Cycle 5: Fmoc-Lys(Boc)-OH; Cycle 6: Fmoc-Trp(Boc)-OH; Cycle 7: Fmoc-Asp(OtBu)-OH; Cycle 8: Fmoc-Asn(Trt)-OH; Cycle 9: Fmoc-Lys(Boc)-OH; Cycle 10: Fmoc-Lys(Boc)-OH; Cycle 11: Fmoc-Gly-OH; Cycle 12: Fmoc-Lys(Boc)-OH; Cycle 13: Fmoc-Gln(Trt)-OH; Cycle 14: Fmoc-Ala-OH; Cycle 15: Fmoc-Leu-OH; Cycle 16: Fmoc-Leu-OH; Cycle 17: Fmoc-Trp(Boc)-OH; Cycle 18: Fmoc-Asn(Trt)-OH; Cycle 19: Fmoc-Val-OH; Cycle 20: Fmoc-Phe-OH; Cycle 21: Fmoc-Asp(OtBu)-OH; Cycle 22: Fmoc-Gln(Trt)-OH; Cycle 23: Fmoc-Gln(Trt)-OH; Cycle 24: Fmoc-His(Trt)-OH; Cycle 25: Fmoc-Ile-OH; Cycle 26: Fmoc-Lys(Boc)-OH; Cycle 27: Fmoc-Asp(OtBu)-OH; Cycle 28: Fmoc-Met-OH; Cycle 29: Fmoc-Ala-OH; Cycle 30: Fmoc-Ile-OH; Cycle 31: Fmoc-Tyr(tBu)-Ser(psiMe,Me,Pro)-OH; Cycle 32: Fmoc-Asp(OtBu)-OH; Cycle 33: Fmoc-Ser(tBu)-OH; and Cycle 34: Fmoc-A6c-OH. Once the peptide backbone was complete, the resin was treated with piperidine solution to remove the N-terminal Fmoc group, followed by treatment with the standard capping procedure in order to acetylate the N-terminus. The resin was then thoroughly washed with DMF and then transferred back to the 50 ml conical tube using DMF as the transfer solvent.
[0273] The resin was deprotected and cleaved from the resin via treatment with 5 ml of the following reagent; 5% TIS, 2% water, 5% (w/v) dithiothrieitol (DTT), 88% TFA, and allowed to mix for 3.5 hours. The filtrate was collected into 45 ml of cold anhydrous ethyl ether. The precipitate was pelleted for 10 minutes at 3500 RPM in a refrigerated centrifuge. The ether was decanted, and the peptide re-suspended in fresh ether. The ether workup was performed a total of 2 times. Following the last ether wash the peptide was allowed to air dry to remove residual ether. The peptide pellet was resuspended in 8 ml of acetonitrile (Acn) followed by 8 ml of de-ionized water, and allowed to fully dissolve. The peptide solution was then analyzed by mass spectrometry. Mass analysis employing electrospray ionization identified a main product containing a mass of 4358.0 Daltons; corresponding to the acetylated,linear product. The crude product (approximately 500 mg) was analysed by HPLC, employing a 250×4.6 mm C18 column (Phenomenex; Torrance, Calif., USA) using a gradient of 2-80% acetonitrile (0.1% TFA) over 30 minutes. Analytical HPLC identified a product with 38% purity. The crude peptide was then purified on a preparative HPLC equipped with a C18 reverse phase column using a 10-60% acetonirile (0.1% TFA) over 50 minutes at a 10 ml/min flowrate. The purified peptide was then lyophilized yielding 15 mg of peptide. The linear peptide was then derivatized with N-propylmaleimide (Pma) to generate the propylsuccinimide (Psu) derivative on the Cysteine side chain. The purified linear peptide was brought up in water, adjusted to pH 6.5 with ammonium carbonate, at 5 mg/ml. Five equivalents of Pma was added with constant stirring for 30 seconds. The derivatized peptide solution was then analyzed by mass spectrometry. Mass analysis identified a main product containing a mass of 4498.6 Daltons; corresponding to the desired Psu derivatized product. The product was then re-purified via preparative HPLC using a similar gradient as before. The purified product was analyzed by HPLC for purity (95.2%) and mass spectrometry (4498.6 Daltons) and subsequently lyophilized. Following lyophillization, 4.3 mg of purified product was obtained representing a 1% yield.
EXAMPLE 12
[Ac-Ac6c 7 , Orn(N—C(O)—(CH 2 ) 12 —CH 3 ) 31 ]hGIP(7-42)-OH
[0274] Solid-phase peptide synthesis was used to assemble the peptide using microwave-assisted Fmoc Chemistry on a Liberty Peptide Synthesizer (CEM; Matthews, N.C., USA) at the 0.1 mmole scale. Pre-loaded Fmoc-Gln(Trt)-Wang resin (0.59 mmole/g; Novabiochem, San Diego, Calif., USA) was used to generate the C-terminal acid peptide. The resin (0.17 g) was placed in a 50 ml conical tube along with 15 ml of dimethylformamide (DMF) and loaded onto a resin position on the synthesizer. The resin was then quantitatively transferred to the reaction vessel via the automated process. The standard Liberty synthesis protocol for 0.1 mmole scale synthesis was used. This protocol involves deprotecting the N-terminal Fmoc moiety via an initial treatment with 7 ml of 20% piperidine, containing 0.1M N-hydroxybenzotriazole (HOBT), in DMF. The initial deprotection step was for 30 seconds with microwave power (45 watts, maximum temperature of 75° C.), and nitrogen bubbling (3 seconds on/7 seconds off). The reaction vessel was then drained and a second piperidine treatment, identical to the first treatment, except that it was for a 3-minute duration. The resin was then drained and thoroughly washed with DMF several times. The protected amino acid, Fmoc-Thr(tBu)-OH, prepared as 0.2M stock solution in DMF, was then added (2.5 ml, 5 eq.), followed by 1.0 ml of 0.45M (4.5 eq.) HBTU [2-(1H-benzo-triazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosaphate] in DMF. This was followed by the addition of 0.5 ml of 2M (10 eq.) DIPEA (diisopropylethylamine) in NMP (N-methylpyrrollidinone). The coupling step was performed for 5 minutes using 20 watts of microwave power, a max temperature of 75° C., and the same rate of nitrogen bubbling.
[0275] Following the initial coupling step the reaction vessel was drained to waste and the coupling step repeated. Cycle 2 was then initiated similar to cycle 1. All amino acids were introduced similarly and a double-coupling strategy was employed throughout the entire sequence. Cycles 1-3, 19-20, 25-26, and 30-34 contained a capping procedure immediately following the coupling step. Capping was performed by adding 7 ml of 0.5M acetic anhydride, containing 0.015M HOBT in NMP, along with 2 ml of the 2M DIPEA solution using a multi-step microwave protocol: 50 watts of power for 30 seconds (65° C. max temperature), followed by 30 seconds of microwave power off, followed by a second round of 30 seconds of microwave power on (50 watts), and then again 30 seconds of no microwave power. The resin was then drained and thoroughly washed with DMF. The following amino acids (Advanced Chemtech; Louisville, Ky., USA) were used; Cycle 1: Fmoc-Thr(tBu)-OH; Cycle 2: Fmoc-Ile-OH; Cycle 3: Fmoc-Asn(Trt)-OH; Cycle 4: Fmoc-His(Trt)-OH; Cycle 5: Fmoc-Lys(Boc)-OH; Cycle 6: Fmoc-Trp(Boc)-OH; Cycle 7: Fmoc-Asp(OtBu)-OH; Cycle 8: Fmoc-Asn(Trt)-OH; Cycle 9: Fmoc-Lys(Boc)-OH; Cycle 10: Fmoc-Lys(Boc)-OH; Cycle 11: Fmoc-Orn(Mtt)-OH; Cycle 12: Fmoc-Lys(Boc)-OH; Cycle 13: Fmoc-Gln(Trt)-OH; Cycle 14: Fmoc-Ala-OH; Cycle 15: Fmoc-Leu-OH; Cycle 16: Fmoc-Leu-OH; Cycle 17: Fmoc-Trp(Boc)-OH; Cycle 18: Fmoc-Asn(Trt)-OH; Cycle 19: Fmoc-Val-OH; Cycle 20: Fmoc-Phe-OH; Cycle 21: Fmoc-Asp(OtBu)-OH; Cycle 22: Fmoc-Gln(Trt)-OH; Cycle 23: Fmoc-Gln(Trt)-OH; Cycle 24: Fmoc-His(Trt)-OH; Cycle 25: Fmoc-Ile-OH; Cycle 26: Fmoc-Lys(Boc)-OH; Cycle 27: Fmoc-Asp(OtBu)-OH; Cycle 28: Fmoc-Met-OH; Cycle 29: Fmoc-Ala-OH; Cycle 30: Fmoc-Ile-OH; Cycle 31: Fmoc-Tyr(tBu)-Ser(psiMe,Me,Pro)-OH; Cycle 32: Fmoc-Asp(OtBu)-OH; Cycle 33: Fmoc-Ser(tBu)-OH; and Cycle 34: Fmoc-A6c-OH. The coupling protocol for Fmoc-His(Trt)-OH was a slightly modified version of the standard protocol. The microwave power was off for the first 2 minutes, followed by 4 minutes with microwave power on (20 watts; max temperature of 50° C.). Once the peptide backbone was complete, the resin was treated with piperidine solution to remove the N-terminal Fmoc group, followed by treatment with the standard capping procedure in order to acetylate the N-terminus. The resin was then treated with 12 ml of 1% trifluoroacetic acid (TFA)/5% triisopropylsilane (TIS) in dichloromethane (DCM) for 5 minutes and a N 2 sparge rate of 5 seconds on and 10 seconds off. The resin was then drained and again treated with the 1% TFA/5% TIS in DCM solution for 5 minutes. This was performed a total of 7 times to effectively remove the Mtt moiety from the Ornithine side chain. The resin was thoroughly washed with DCM several times, and then treated with the standard piperidine treatment in order to neutralize residual TFA salt on the 8N of ornithine. Myristic acid, (CH 3 —(CH 2 ) 12 —COOH; Aldrich, St. Louis, Mo., USA) prepared as a 0.2M solution in DMF, was coupled to the ornithine side chain using the standard amino acid coupling protocol. The resin was then thoroughly washed with DMF and then transferred back to the 50 ml conical tube using DMF as the transfer solvent.
[0276] The resin was deprotected and cleaved from the resin via treatment with 5 ml of the following reagent; 5% TIS, 2% water, 5% (w/v) dithiothrieitol (DTT), 88% TFA, and allowed to mix for 3.5 hours. The filtrate was collected into 45 ml of cold anhydrous ethyl ether. The precipitate was pelleted for 10 minutes at 3500 RPM in a refrigerated centrifuge. The ether was decanted, and the peptide re-suspended in fresh ether. The ether workup was performed a total of 2 times. Following the last ether wash the peptide was allowed to air dry to remove residual ether. The peptide pellet was resuspended in 8 ml of acetonitrile (Acn) followed by 8 ml of de-ionized water, and allowed to fully dissolve. The peptide solution was then analyzed by mass spectrometry. Mass analysis employing electrospray ionization identified a main product containing a mass of 4636.5 Daltons; corresponding to the desired product. The crude product was analysed by HPLC, employing a 250×4.6 mm C18 column (Phenomenex; Torrance, Calif., USA) using a gradient of 2-80% acetonitrile (0.1% TFA) over 30 minutes. Analytical HPLC identified a product with 37% purity. The peptide was then purified on a preparative HPLC equipped with a C18 column using a similar elution gradient. The purified product was re-analyzed by HPLC for purity (95.20%) and mass spectrometry (4636.6 Daltons) and subsequently lyophilized. Following lyophillization, 3 mg of purified product was obtained representing a 0.6% yield.
EXAMPLE 22
[Ac-A6c 7 , Cys(Hsu) 31 ]hGUP(7-42)-OH
[0277] Solid-phase peptide synthesis was used to assemble the peptide using microwave-assisted Fmoc Chemistry on a Liberty Peptide Synthesizer (CEM; Matthews, N.C., USA) at the 0.1 mmole scale. Pre-loaded Fmoc-Gln(Trt)-Wang resin (0.59 mmole/g; Novabiochem, San Diego, Calif., USA) was used to generate the C-terminal acid peptide. The resin (0.17 g) was placed in a 50 ml conical tube along with 15 ml of dimethylformamide (DMF) and loaded onto a resin position on the synthesizer. The resin was then quantitatively transferred to the reaction vessel via the automated process. The standard Liberty synthesis protocol for 0.1 mmole scale synthesis was used. This protocol involves deprotecting the N-terminal Fmoc moiety via an initial treatment with 7 ml of 20% piperidine, containing 0.1M N-hydroxybenzotriazole (HOBT), in DMF. The initial deprotection step was for 30 seconds with microwave power (45 watts, maximum temperature of 75° C.), and nitrogen bubbling (3 seconds on/7 seconds off). The reaction vessel was then drained and a second piperidine treatment, identical to the first treatment, except that it was for a 3-minute duration. The resin was then drained and thoroughly washed with DMF several times. The protected amino acid, Fmoc-Thr(tBu)-OH, prepared as 0.2M stock solution in DMF, was then added (2.5 ml, 5 eq.), followed by 1.0 ml of 0.45M (4.5 eq.) HBTU [2-(1H-benzo-triazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosaphate] in DMF. This was followed by the addition of 0.5 ml of 2M (10 eq.) DIPEA (diisopropylethylamine) in NMP (N-methylpyrrollidinone). The coupling step was performed for 5 minutes using 20 watts of microwave power, a max temperature of 75° C., and the same rate of nitrogen bubbling.
[0278] Following the initial coupling step the reaction vessel was drained to waste and the coupling step repeated. Cycle 2 was then initiated similar to cycle 1. All amino acids were introduced similarly and a double-coupling strategy was employed throughout the entire sequence. Cycles 1-3, 19-20, 25-26, and 30-34 contained a capping procedure immediately following the coupling step. Capping was performed by adding 7 ml of 0.5M acetic anhydride, containing 0.015M HOBT in NMP, along with 2 ml of the 2M DIPEA solution using a multi-step microwave protocol: 50 watts of power for 30 seconds (65° C. max temperature), followed by 30 seconds of microwave power off, followed by a second round of 30 seconds of microwave power on (50 watts), and then again 30 seconds of no microwave power. The resin was then drained and thoroughly washed with DMF. The following amino acids (Advanced Chemtech, Louisville, Ky,, USA) were used: Cycle 1: Fmoc-Thr(OtBu)-OH; Cycle 2: Fmoc-Ile-OH; Cycle 3: Fmoc-Asn(Trt)-OH; Cycle 4: Fmoc-His(Trt)-OH; Cycle 5: Fmoc-Lys(Boc)-OH; Cycle 6: Fmoc-Trp(Boc)-OH; Cycle 7: Fmoc-Asp(OtBu)-OH; Cycle 8: Fmoc-Asn(Trt)-OH; Cycle 9: Fmoc-Lys(Boc)-OH; Cycle 10: Fmoc-Lys(Boc)-OH; Cycle 11: Fmoc-Cys(Trt)-OH; Cycle 12: Fmoc-Lys(Boc)-OH; Cycle 13: Fmoc-Gln(Trt)-OH; Cycle 14: Fmoc-Ala-OH; Cycle 15: Fmoc-Leu-OH; Cycle 16: Fmoc-Leu-OH; Cycle 17: Fmoc-Trp(Boc)-OH; Cycle 18: Fmoc-Asn(Trt)-OH; Cycle 19: Fmoc-Val-OH; Cycle 20: Fmoc-Phe-OH; Cycle 21: Fmoc-Asp(OtBu)-OH; Cycle 22: Fmoc-Gln(Trt)-OH; Cycle 23: Fmoc-Gln(Trt)-OH; Cycle 24: Fmoc-His(Trt)-OH; Cycle 25: Fmoc-Ile-OH; Cycle 26: Fmoc-Lys(Boc)-OH; Cycle 27: Fmoc-Asp(OtBu)-OH; Cycle 28: Fmoc-Met-OH; Cycle 29: Fmoc-Ala-OH; Cycle 30: Fmoc-Ile-OH; Cycle 31: Fmoc-Tyr(tBu)-Ser(psiMe,Me,Pro)-OH; Cycle 32: Fmoc-Asp(OtBu)-OH; Cycle 33: Fmoc-Ser(tBu)-OH; and Cycle 34: Fmoc-A6c-OH. Once the peptide backbone was complete, the resin was treated with piperidine solution to remove the N-terminal Fmoc group, followed by treatment with the standard capping procedure in order to acetylate the N-terminus. The resin was then thoroughly washed with DMF and then transferred back to the 50 ml conical tube using DMF as the transfer solvent.
[0279] The resin was deprotected and cleaved from the resin via treatment with 5 ml of the following reagent; 5% TIS, 2% water, 5% (w/v) dithiothrieitol (DTT), 88% TFA, and allowed to mix for 3.5 hours. The filtrate was collected into 45 ml of cold anhydrous ethyl ether. The precipitate was pelleted for 10 minutes at 3500 RPM in a refrigerated centrifuge. The ether was decanted, and the peptide re-suspended in fresh ether. The ether workup was performed a total of 2 times. Following the last ether wash the peptide was allowed to air dry to remove residual ether. The peptide pellet was resuspended in 8 ml of acetonitrile (Acn) followed by 8 ml of de-ionized water, and allowed to fully dissolve. The peptide solution was then analyzed by mass spectrometry. Mass analysis employing electrospray ionization identified a main product containing a mass of 4414.9 Daltons; corresponding to the linear product. The crude product (approximately 500 mg) was analysed by HPLC, employing a 250×4.6 mm C18 column (Phenomenex; Torrance, Calif., USA) using a gradient of 2-80% acetonitrile (0.1% TFA) over 30 minutes. Analytical HPLC identified a product with 58% purity. The crude peptide was then derivatized with N-hexylmaleimide (Hma) to generate the hexylsuccinimide (Hsu) derivative on the Cysteine side chain. The crude linear peptide was brought up in water, adjusted to pH 6.5 with ammonium carbonate, at 5 mg/ml. Five equivalents of Hma was added with constant stirring for 30 seconds. Excess Hma was quenched using 5 eq. of dithiothreitol (DTT). The derivatized peptide solution was then analyzed by mass spectrometry. Mass analysis identified a main product containing a mass of 4596.1 Daltons; corresponding to the desired Hsu derivatized product. The product was then re-purified via preparative HPLC using a similar gradient as before. The purified product was analyzed by HPLC for purity (95.4%) and mass spectrometry (4596.4 Daltons) and subsequently lyophilized. Following lyophillization, 28.1 mg of purified product was obtained representing a 6.1% yield.
[0280] The PEGylated GIP compounds disclosed herein can be synthesized substantially according to the procedure described for the synthesis of the compound of Example 2, by using PEG-maleimide as the starting material instead of N-propylmaleimide used in Example 2.
[0281] Other peptides of the invention can be prepared by a person of ordinary skill in the art using synthetic procedures analogous to those disclosed in the foregoing examples. Physical data for the compounds exemplified herein are given in Table 1.
[0000]
TABLE 1
Example
Mol. Wt.
Mol. Wt.
% Purity
Number
(Expected)
(ESI-MS)
(HPLC)
1
4368.92
4368.8
96.70
2
4498.06
4498.6
95.20
3
4497.12
4497.5
99.90
4
4474.08
4473.9
99.90
5
4425.01
4425.0
99.90
6
4496.13
4496.5
99.90
7
4497.12
4496.7
99.90
8
4483.05
4482.4
99.90
9
4483.05
4482.7
99.90
10
4554.17
4554.0
99.90
11
4483.05
4482.7
98.40
12
4636.38
4636.6
95.20
13
4580.27
4580.7
96.70
14
4538.23
4538.8
99.90
15
4692.48
4693.1
95.00
16
4524.16
4524.9
96.20
17
4482.13
4482.6
99.90
18
4580.27
4580.9
95.70
19
4523.22
4523.7
95.50
20
4481.18
4481.4
99.90
21
4635.43
4636.0
95.30
22
4596.25
4596.4
95.40
23
4554.21
4554.6
95.80
24
4509.11
4509.8
99.10
25
4509.11
4509.9
99.90
26
4787.37
4788.4
99.90
27
4497.05
4496.8
99.90
28
3530.07
3530.0
99.90
29
3159.62
3159.6
96.40
30
4701.35
4701.7
96.40
31
4659.31
4660.0
95.10
32
3064.50
3064.7
99.90
33
3306.80
3306.7
96.30
34
3264.76
3264.6
98.20
35
2990.40
2990.8
96.83
36
3004.42
3004.7
99.90
37
2990.44
2990.8
97.20
38
4270.80
4270.6
99.90
39
4413.06
4413.5
99.90
40
4497.12
4497.6
96.90
41
4485.11
4485.7
96.40
42
4893.49
4894.4
99.90
43
4847.45
4848.1
99.90
44
4911.51
4911.4
99.90
45
4891.45
4891.0
99.90
46
4935.58
4935.8
99.90
47
5150.9
5151.4
99.9
Functional Assays
[0282] A. In Vitro hGIP Receptor Binding Assay
[0283] Membranes for in vitro receptor binding assays were prepared by homogenizing the CHO-K1 clonal cells expressing the human recombinant GIP receptor, with a Brinkman Polytron (setting 6, 15 sec), in ice-cold 50 mM Tris-HCl and then subjected to two centrifugations at 39,000 g for 10 minutes, with a resuspension in fresh buffer in between. For the assay, aliquots of the washed membrane preparations were incubated (100 minutes at 25° C. with 0.05 nM [ 125 I]GIP (approximately 2200 Ci/mmol) in 50mM Tris-HCl, 0.1 mg,/mlbacitracin, and 0.1% BSA. The final assay volume was 0.5 ml. The incubations were terminated by rapid filtration through GF/C filters (pre-soaked in 0.5% polyethylenimine) using a Brandel filtration manifold. Each tube and filter were then washed three times with 5-ml aliquots of ice-cold buffer. Specific binding was defined as the total radioligand bound minus that bound in the presence of 1000 nM GIP. In vitro hGIP receptor binding data for the compounds exemplified herein are given in Table 2.
B. Human and Rat Plasma Half-Life Assay
[0284] GIP peptide (50 μL 1 mg/ml) was added to 450 μL plasma (human or rat), vertexed briefly and incubated at 37° C. 50 μl, was removed at various times, like at 0, 1, 2, 3, 4, 8, 24, 32, 48, 56, 72 hours, mixed with 5 μL formic acid and 150 μL acetonitrile in a microcentrifuge tube, vertexed, and centrifuged for 10 minutes at 10K rpm. The supernatant was transferred to an injection vial and analyzed by LC-MS. The LC-MS system consisted of an API4000 mass spectrometer with an ESI probe. Positive ion mode and full scan detection were used. HPLC separation was carried out on a Luna 3μ C8 (2), 2×30 mm column with a gradient from 90% A to 90% B in 10 minutes at a flow rate of 0.3 ml/min. Buffer A was 1% formic acid in water and buffer B was 1% formic acid acetonitrile. Human and rat plasma half-life data for the compounds exemplified herein are given in Table 2.
[0000]
TABLE 2
Example
Human Plasma
Rat Plasma
Number
Ki (nM)
T½ (hr)
T½ (hr)
1
N/A
>72
11.0
2
532.19
13.7
7.2
3
75.73
16.4
5.6
4
332.97
10.0
6.0
5
442.49
7.8
8.5
6
486.41
8.0
3.2
7
735.40
7.9
1.6
8
416.57
N/A
N/A
9
686.96
N/A
N/A
10
963.06
8.0
2.6
11
127.00
N/A
N/A
12
178.00
7.3
>72
13
N/A
17.8
19.0
14
N/A
4.1
15.3
15
N/A
5.2
>72
16
N/A
>50
30.0
17
N/A
>50
9.4
18
N/A
13.8
6.3
19
N/A
18.9
10.7
20
274.00
9.4
13.9
21
163.50
8.0
>72
22
N/A
7.7
5.0
23
772.00
11.7
5.3
24
194.33
26.3
12.2
25
159.39
>50
13.7
26
546.10
30.1
17.5
27
7.92
N/A
N/A
28
114.78
8.8
4.1
29
48.32
12.2
7.0
30
574.00
7.2
7.6
31
277.01
4.4
5.1
32
68.54
24.1
60.3
33
77.48
13.6
10.2
34
101.42
11.3
7.4
35
734.33
16.5
23.0
36
212.33
21.9
21.6
37
170.00
13.5
28.5
38
472.00
N/A
N/A
39
N/A
31.1
13.7
40
403.33
4.1
6.9
41
205.48
5.9
3.7
42
293.90
>51
10.3
43
800.01
>53
2.3
44
12.89
48.8
9.9
45
50.43
64.2
4.3
46
91.78
30.8
11.9
47
N/A
N/A
N/A
C. Determination of Cyclic AMP Stimulation
[0285] 1×105 CHO-K1 cells expressing the human recombinant GIP receptor or RIN-5F insulinoma cells were seeded overnight into 24-well cell culture plates (Corning Incorporate, Corning, N.Y., USA). For the assay, the cells were preincubated in 500 μl of Hanks balanced salt solution (Sigma, St. Louis, Mo., USA) with 0.55 mM IBMX (Sigma, St. Louis, Mo., USA) adjusted to pH 7.3 for 10 minutes. GIP or its analogs was then added at a concentration of 100 nM. Following a 30-minute incubation at 37° C., the plates were placed on ice and 500 μl of ice-cold absolute ethanol was added to stop the reaction. The contents of the wells were collected, spun at 2,700 g for 20 minutes at 4° C. to remove cellular debris. The cAMP levels in the supernatants were determined by radioimmunoassay (New England Nuclear, Boston, Mass., USA).
Administration
[0286] The peptides of this invention can be provided in the form of pharmaceutically acceptable salts. Examples of such salts include, but are not limited to, those formed with organic acids (e.g., acetic, lactic, maleic, citric, malic, ascorbic, succinic, benzoic, methanesulfonic, toluenesulfonic, or pamoic acid), inorganic acids (e.g., hydrochloric acid, sulfuric acid, or phosphoric acid), and polymeric acids (e.g., tannic acid, carboxymethyl cellulose, polylactic, polyglycolic, or copolymers of polylactic-glycolic acids). A typical method of making a salt of a peptide of the present invention is well known in the art and can be accomplished by standard methods of salt exchange. Accordingly, the TFA salt of a peptide of the present invention (the TFA salt results from the purification of the peptide by using preparative HPLC, eluting with TFA containing buffer solutions) can be converted into another salt, such as an acetate salt by dissolving the peptide in a small amount of 0.25 N acetic acid aqueous solution. The resulting solution is applied to a semi-prep HPLC column (Zorbax, 300 SB, C-8). The column is eluted with (1) 0.1N ammonium acetate aqueous solution for 0.5 hrs, (2) 0.25N acetic acid aqueous solution for 0.5 hrs, and (3) a linear gradient (20% to 100% of solution B over 30 minutes) at a flow rate of 4 ml/min (solution A is 0.25N acetic acid aqueous solution; solution B is 0.25N acetic acid in acetonitrile/water, 80:20). The fractions containing the peptide are collected and lyophilized to dryness.
[0287] The dosage of active ingredient in the compositions of this invention may be varied; however, it is necessary that the amount of the active ingredient be such that a suitable dosage form is obtained. The selected dosage depends upon the desired therapeutic effect, on the route of administration, and on the duration of the treatment. In general, an effective dosage for the activities of this invention is in the range of 1×10 −7 to 200 mg/kg/day, preferably 1×10 4 to 100 mg/kg/day, which can be administered as a single dose or divided into multiple doses.
[0288] The compounds of this invention can be administered by oral, parenteral (e.g., intramuscular, intraperitoneal, intravenous or subcutaneous injection, or implant), nasal, vaginal, rectal, sublingual, or topical routes of administration, and can be formulated with pharmaceutically acceptable carriers to provide dosage forms appropriate for each route of administration.
[0289] Solid dosage forms for oral administration include capsules, tablets, pills, powders and granules. In such solid dosage forms, the active compound is admixed with at least one inert pharmaceutically acceptable carrier such as sucrose, lactose, or starch. Such dosage forms can also comprise, as is normal practice, additional substances other than such inert diluents, e.g., lubricating agents such as magnesium stearate. In the case of capsules, tablets and pills, the dosage forms may also comprise buffering agents. Tablets and pills can additionally be prepared with enteric coatings.
[0290] Liquid dosage forms for oral administration include, without limitation, pharmaceutically acceptable emulsions, solutions, suspensions, syrups, elixirs, and the like, containing inert diluents commonly used in the art, such as water. Besides such inert diluents, compositions can also include adjuvants, such as wetting agents, emulsifying and suspending agents, and sweetening, flavoring and perfuming agents.
[0291] Preparations according to this invention for parenteral administration include, without limitation, sterile aqueous or non-aqueous solutions, suspensions, emulsions, and the like. Examples of non-aqueous solvents or vehicles include propylene glycol, polyethylene glycol, vegetable oils, such as olive oil and corn oil, gelatin, and injectable organic esters such as ethyl oleate. Such dosage forms may also contain adjuvants such as preserving, wetting, emulsifying, and dispersing agents. They may be sterilized by, for example, filtration through a bacteria-retaining filter, by incorporating sterilizing agents into the compositions, by irradiating the compositions, or by heating the compositions. They can also be manufactured in the form of sterile solid compositions which can be dissolved in sterile water, or some other sterile injectable medium immediately before use.
[0292] Compositions for rectal or vaginal administration are preferably suppositories which may contain, in addition to the active substance, excipients such as coca butter or a suppository wax.
[0293] Compositions for nasal or sublingual administration are also prepared with standard excipients well known in the art.
[0294] Further, a compound of this invention can be administered in a sustained release composition such as those described in the following patents and patent applications. U.S. Pat. No. 5,672,659 teaches sustained release compositions comprising a bioactive agent and a polyester. U.S. Pat. No. 5,595,760 teaches sustained release compositions comprising a bioactive agent in a gelable form. U.S. Pat. No. 5,821,221 teaches polymeric sustained release compositions comprising a bioactive agent and chitosan. U.S. Pat. No. 5,916,883 teaches sustained release compositions comprising a bioactive agent and cyclodextrin. PCT publication WO99/38536 teaches absorbable sustained release compositions of a bioactive agent. PCT publication WO00/04916 teaches a process for making microparticles comprising a therapeutic agent such as a peptide in an oil-in-water process.
[0295] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Also, all publications, patent applications, patents and other references mentioned herein are hereby incorporated by reference, each in its entirety.
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There is provided a novel series of analogues of glucose-dependent insulinotropic polypeptide compounds, pharmaceutical compositions containing said compounds, and the use of said compounds as GIP-receptor agonists or antagonists for treatment of GIP-receptor mediated conditions, such as non-insulin dependent diabetes mellitus and obesity.
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BACKGROUND OF THE INVENTION
[0001] This invention relates to machines for tying wire bindings around reinforcement bars as used in the construction of reinforced concrete.
[0002] WO 2007/042785 gives an example of a wire binding machine used for tying wire loops around intersections of steel reinforcement bars for constructing reinforced concrete structures. The design of machine shown in this document has been shown to produce tight and reliable ties in a practical and compact package. However as with any battery-powered tool, it would always be desirable to be able to reduce its power consumption even further in order to extend battery life or allow a smaller and therefore lighter battery to be used.
[0003] The Applicant has now appreciated that one area where a reduction in power consumption might be possible is in the motor used to feed the wire from the spool to the head and to withdraw it again to pull the loop tight prior to spinning.
[0004] When viewed from a first aspect the present invention provides a machine for tying a length of wire around one or more objects comprising a wire feed mechanism adapted to feed wire from a spool during a first phase; and to withdraw the wire during a second phase, said wire feed mechanism comprising a gripping mechanism including a pair of rollers urged together to grip the wire therebetween and drive it in the appropriate direction, said gripping mechanism being configured such that during said second phase, increasing tension in the wire automatically increases the gripping force on the wire.
[0005] Thus it will be seen by those skilled in the art that in accordance with the invention the grip on the wire increases with wire tension during the second, retraction phase. The invention involves a recognition by the Applicant that a much greater gripping force on the wire is required in the second phase, especially during the latter part thereof if the wire is to be pulled tightly around the reinforcement bars. It has been recognised accordingly that during the first phase there is a lower gripping force requirement as it is only necessary for the drive mechanism to overcome the friction encountered by the wire in being withdrawn from the spool and fed through the machine.
[0006] In previously proposed arrangements the grip on the wire was set at a constant high value to ensure sufficient tension could be applied to it during the second, retraction phase to ensure a good tie. However this meant the torque in the driving motor and so the current used by the drive mechanism was higher than it needed to be in the first phase. By employing an automatically increasing grip as the tension in the wire increases as result of wire is drawn tightly, the grip and so current drawn can be kept low during the first phase without compromising how tightly the loop can be drawn during the second phase.
SUMMARY OF THE INVENTION
[0007] There are many possible mechanisms for achieving the functionality set out above. For example a secondary motor or solenoid could be employed to apply the gripping force, e.g. with a feedback mechanism sensitive to the tension in the wire controlling the applied force. Preferably however a purely mechanical arrangement is employed. Preferably at least one of the rollers is connected to a gear which is driven by a drive gear, such as a pinion, connected to a motor. Such connection between the drive gear and the motor could be by it being directly fixed onto the motor driveshaft, or by indirect coupling through a gearbox, clutch or other coupling arrangement.
[0008] The other roller could be entirely passive, i.e. acting as an idler, in which case it would not need a gear. Preferably however it, too is attached to a respective gear. This could be driven by another drive gear, coupled either to the same or a separate motor. Preferably however it is driven by the first roller gear.
[0009] In one set of preferred embodiments the drive gear and the roller gear it engages are mounted to allow a degree of separation between their respective axes such that a gear separation force acting between them is such as to urge the respective roller onto the wire, thereby increasing the gripping force. In such embodiments as the tension in the wire increases, the torque transmitted by the roller and drive gears also increases. Their respective mountings allow the resultant natural tendency to separate to urge the associated roller tighter onto the wire. In a preferred such arrangement the roller is mounted so that its axis can pivot relative to the drive gear about a point offset from the axis of the drive gear.
[0010] In another set of preferred embodiments the axes of the drive and roller gears are at a fixed spacing, the roller gear being mounted to allow it to precess around the drive gear to urge the roller tighter onto the wire. In a preferred embodiment the roller is mounted so that it can pivot towards and away from the wire. The meshing element could for example be mounted on an arm or plate. In a preferred set of embodiments the rotation is centred on the pinion. In a preferred such arrangement the roller is mounted so that its axis can pivot relative to the drive gear about the axis of the drive gear.
[0011] In light of the above it can be seen that in one set of preferred embodiments the roller gear which is engaged by the drive gear is mounted so that its axis can pivot relative to the axis of the drive gear. The pivot axis may either be the drive gear axis or it may be offset from it.
[0012] In either case both rollers could be directly driven and one of the outlined arrangements provided for the other roller. Preferably though only one roller is directly driven and the axis of the other (non-driven) roller is fixed relative to that of the drive gear.
[0013] In general the rollers are preferably resiliently biased together. This can be used to set an initial preload suitable for the first (feed-out) phase.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Certain preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:
[0015] FIG. 1A is a perspective view of a wire tying apparatus above a pair of crossed bars prior to a tying operation being initiated;
[0016] FIG. 1B is a view similar to FIG. 1A with the main mounting bracket removed;
[0017] FIG. 2 sectional view through the apparatus shown in FIG. 1 ;
[0018] FIG. 3 is a view of the apparatus from beneath;
[0019] FIG. 4 is a sectional view similar to FIG. 2 showing the apparatus part-way through a tying operation;
[0020] FIG. 5A is another sectional view showing the wire tensioned prior to twisting;
[0021] FIG. 5B is an enlargement of the circled part of FIG. 5A ;
[0022] FIG. 6 is a diagram illustrating a first embodiment of the invention; and
[0023] FIG. 7 is a diagram illustrating a second embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0024] The embodiments described below with reference to FIGS. 6 and 7 may be applied to any machine for tying wire bindings around a pair of steel concrete reinforcement bars. For the purposes of reference however a specific example of such a machine will be described below with reference to FIGS. 1 to 5 .
[0025] Referring first to FIGS. 1A , 1 A and 2 there are shown two perspective views and a sectional view respectively of part of a wire tying apparatus with certain parts such as the housing, handle, battery, controls, shroud and wire spool removed for clarity. The apparatus is shown situated over a junction where two steel bars 2 cross over each other at right angles. The steel bars 2 are intended to form a rectangular grid to be embedded in a concrete structure in order to reinforce it. Although not shown, a domed shroud is provided around the lower end of the apparatus and has two part-circular depressions so that the apparatus can securely rest on the upper of the two bars 2 without slipping off.
[0026] Sitting in use above the uppermost bar 2 is the rotary head of the apparatus 4 . This includes a horizontal circular base plate 6 extending up from which is a channel 8 which is approximately semi-circular in vertical section and of approximately constant width in the orthogonal direction. In the centre of base plate 6 is a part-spherical depression 9 . The underneath of the base plate 6 is shown in FIG. 3 from which it will be seen that on one side there is a narrow slot 10 corresponding to one end of the semi-circular channel and on the other side of the plate 6 corresponding to the other end of the channel is a funnel region 12 .
[0027] Returning to FIGS. 1A , 1 B and 2 , attached to the semi-circular channel 8 is the upper cylindrical portion of the head 14 which is rotatably mounted in the cylindrical portion 16 a of a bracket member mounted to the housing (not shown) by a flange portion 16 b (omitted from FIG. 1A ). The upper head portion is supported by two rotary bearings 18 . A toothed gear wheel, 20 is provided fixed at the top of the head to allow it to be driven by a motor 22 via a worm gear.
[0028] Extending through the gear wheel 20 into the open upper end of the head 4 is a solenoid assembly comprising a cylindrical outer tube 26 housing the coil and an inner plunger 28 which is able to slide vertically relative to the coil 26 . At the bottom end of the plunger 28 is an actuating disc 30 , the purpose of which will be explained later.
[0029] The internal construction of the head 4 will now be described. On the left hand side as seen from FIG. 2 , there may be seen a pivotally mounted angled clutch lever 32 . A pair of compression springs 36 act on the longer, upper arm of the lever 32 so as to bias the lever in an anti-clockwise direction in which the shorter, lower arm is pressed downwardly. Of course any number of springs might be used. To the right of the clutch lever 32 are a series of roller wheels 38 a , 38 b , 38 c the purpose of which will be explained below. A similar clutch lever is provided displaced approximately 180 degrees around the head. This is not therefore visible in the sectional view.
[0030] To the left of the upper head portion 14 connected to the main bracket flange portion 16 b is a wire feed inlet guide 40 which receives the free end of wire 46 from a wire feed module described in greater detail below with reference to FIGS. 6 and 7 .
[0031] An example of a wire feed mechanism which embodies the invention is shown in FIG. 6 . Here it will be seen that two meshing gears 102 , 103 are rotatably mounted on respective arms 104 , 106 . The arms 104 , 106 are mounted for at least limited pivotal movement about respective pivot axes 105 , 107 on a support plate 108 . A set screw 110 is used to set the position of the right-hand arm and thus act as a stop against clockwise pivotal movement of the right-hand mounting arm 106 . The left-hand arm 104 is similarly acted upon by an adjustable spring stop 112 . Between them the set screw 110 and adjustable spring 112 act to provide a resilient force biasing the two gears 102 , 103 together. Behind each gear 102 , 103 and attached to the same respective shafts are respective friction rollers which grip the wire 46 that passes between them.
[0032] The support plate 108 has an extension 116 on one side which mounts a motor (not visible) that drives a pinion 118 . The pinion 118 engages the left-hand roller gear 102 so that rotation of the pinion drives the left roller gear 102 directly, with the right roller gear 103 being driven indirectly by the left one. It will be noted that the
[0033] axis 119 of the pinion 118 is offset from the axis 105 of the driven roller gear 102 .
[0034] Operation of the wire tying apparatus will now be described. The apparatus is first brought down onto the uppermost of a pair of steel reinforcing bars 2 which are crossed at right angles. When the shroud 42 is properly resting on the bar 2 , the presence of the steel will be sensed by the two Hall effect sensors 44 which will allow the tying operation to be commenced. If the operator should attempt to commence the tying operation before both Hall effect sensors 44 sense the presence of the steel bar 2 , a warning light such as an LED is illuminated and further operation of the apparatus is prevented.
[0035] Once the steel bar 2 is properly sensed, the operator may commence the tying operation. The first part of this operation is to energise the solenoid coil 26 which pushes the plunger member 28 downwardly. This causes the actuating member 30 at the end of the plunger to be pressed downwardly onto the upper arms of the clutch levers 32 to press them down against the respective compression springs 36 and therefore raise the shorter, lower arms. This is the position which is shown in FIG. 2 .
[0036] Thereafter the main motor 22 is, if necessary, operated just long enough to rotate head 4 via the worm drive and gear wheel 24 , 20 so that a channel for receiving the wire 46 is in correct alignment with the wire feed inlet guide 40 . This is called the “park” position.
[0037] Once the head 4 is in the “park” position, the wire feed module is operated to feed wire form the spool (not shown). With reference to FIG. 6 the motor driving the pinion is operated to drive it anticlockwise in order to drive the two friction rollers to feed the wire 46 downwardly in the sense of FIG. 6 . Of course this corresponds to feeding it rightwards into the machine as it is oriented in FIG. 2 . The wire 46 is therefore fed into the wire inlet guide 40 and into the aligned channel in the upper head portion 14 . The wire is fed in horizontally and encounters the first of the passive rollers 38 a . The first roller 38 a causes the wire to bend downwardly slightly so that it passes between the second and third rollers 38 b , 38 c . The relative positions of the three passive rollers 38 a , 38 b , 38 c is such that when the wire 46 emerges from them it is bent so as to have an arcuate set. As the wire 46 continues to be driven by the wire feed module, it encounters and is guided by the inner surface of the semi-circular channel 8 .
[0038] When the wire 46 emerges from the channel 8 , its arcuate set causes it to continue to describe an approximately circular arc, now unguided in free space, around the two reinforcing bars. This is shown in FIG. 4 . As the wire 46 continues to be driven, the free end will eventually strike the mouth of the funnel region 12 in the bottom of the base plate 6 and therefore be guided back into the semi-circular channel 8 . However it is not guided back precisely diametrically opposite where it was issued from but rather slightly laterally offset therefrom. This allows the receiving means in the form of a further clutch lever (not shown) to be located next to the first clutch lever 32 which enables the apparatus to be kept relatively compact.
[0039] Throughout the wire feed operation the wire encounters relatively little resistance. The gripping force provided by the spring stop 112 (see FIG. 6 ) acting on the friction rollers through the mounting arm 104 is sufficient to prevent slipping.
[0040] As the free end of the wire re-enters the semi-circular channel 8 , it encounters the second clutch lever. This can be detected by sensing a slight displacement of the lever or by a separate sensor such as a micro switch, Hall effect sensor or other position detection means.
[0041] Once the free end of the wire 46 is detected, the motor driving the pinion 118 is stopped and therefore the wire does not advance any further. At this point the solenoid coil 26 is then de-energised which causes the plunger 28 to be retracted by a spring (not shown) which releases the two clutch levers 32 so that their respective compression springs 36 act to press their lower arms against the two ends of the wire loop and therefore hold the wire 46 in place.
[0042] The wire feed motor is then driven in reverse, i.e, to drive the pinion clockwise in order to retract the wire 46 upwards as viewed from FIG. 6 and so apply tension to the wire loop which draws the wire in around the reinforcing bars 2 , see FIG. 5A . FIG. 5B shows detail of the clutch lever 32 on the feed side clamping the end of the wire 46 . A similar arrangement clamps the other end of the wire as explained above.
[0043] As the wire loop gets tighter the tension in the wire 46 increases. This translates into an increase in the torque applied by the pinion 118 to the driven roller gear 102 . The result of this is a tendency for the pinion 118 and roller gear 102 to separate—i.e. move out of mesh. This is allowed to a limited extent by the pivotal mounting of the roller gear 102 which thus forces the gear 102 and its associated roller tighter against the wire to increase the gripping force on the wire significantly. The other roller provides a reaction force because of its mounting on the pivot arm 106 acted on by the fixed set screw 110 . The relative spacings of the gears 118 , 102 , 103 is such that the pivot arm cannot move enough for the pinion 118 and roller gear 102 to come fully out of mesh.
[0044] This arrangement acts as a positive feedback system since higher the gripping force the greater the force that can imparted to the wire 46 . To give an example during the wire feed phase the compression in the wire might only be 20 Newtons, whereas at the maximum tension when the wire loop is pulled fully tight it can rise to 120 Newtons. When the torque on the motor reaches a predetermined threshold (e.g. as measured by its drawn current) the retraction phase is stopped. The clutches 32 maintain the tension in the loop.
[0045] When the wire 46 is fully tensioned it will be seen from FIG. 5A that the two ends of the loop are pulled up almost vertically from their initial circular profile. As the head 4 tries to start rotating at the beginning of the twisting operation the torque supplied by the head motor 22 is sufficient to shear the wire at the point where it crosses from the inlet guide 40 to the upper head portion 14 without the need for it to be cut. If necessary an initial surge current (e.g. boosted by a charge stored in a capacitor) can be supplied to the motor 22 to deliver an initial spike in torque but this is not essential. With the wire thus broken, the head 4 begins to twist the sides of the loop together above the reinforcing bars 2 as is known per se in the art.
[0046] FIG. 7 shows a different embodiment of the wire feed module although components common to the first embodiment are denoted by the same reference numerals. In this embodiment the shaft of the indirectly driven roller and its gear 103 is fixedly mounted on the base plate 120 . On the other hand the directly driven roller and its gear 102 are mounted on a pivoting arm 122 which is this time pivoted, approximately at its centre, about the axis 119 of the driving pinion 118 . A set spring 105 is provided but this acts on the other end of the lever arm 122 to the roller gear 102 . In the rest position shown in FIG. 7 the arm 122 is inclined slightly so that it is not perpendicular to the wire 46 .
[0047] During the initial feeding phase of the wire 46 , operation is similar to the first embodiment with the pinion being driven anti-clockwise and the gripping force on the wire being provided by the set spring 112 . During the retraction phase however, in which the wire 46 is pulled upwardly as seen from FIG. 7 , the pinion 118 and driven roller gear 102 will not come out of mesh since they are effectively mounted at a fixed axial spacing because the pivot axis of the arm is the same as the axis of the pinion. Instead as tension in the wire 46 increases, the arm 122 will tend to pivot clockwise a small amount to allow the roller gear 102 to precess around the pinion 118 and so bring it towards the perpendicular. This reduces the centre-to-centre spacing of the two rollers and so increases the gripping force on the wire.
[0048] Again a positive feedback loop is set up until a threshold torque in the motor is reached as in the previous embodiment.
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A machine ( 4 ) for tying a length of wire ( 46 ) around one or more objects ( 2 ) comprising a wire feed mechanism adapted to feed wire ( 46 ) from a spool during a first phase; and to withdraw the wire ( 46 ) during a second phase, said wire feed mechanism comprising a gripping mechanism ( 102, 103 ) including a pair of rollers urged together to grip the wire ( 46 ) therebetween and drive it in the appropriate direction, said gripping mechanism ( 102, 103 ) being configured such that during said second phase, increasing tension in the wire ( 46 ) automatically increases the gripping force on the wire ( 46 ).
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BACKGROUND OF THE INVENTION
The invention relates to a reinforcing strip comprising steel and adapted for the reinforcement of the belt of rubber vehicle tires, and having a significantly higher bending stiffness in the plane of the strip than in the longitudinal plane (i.e. a plane comprising the longitudinal axis of the strip), perpendicular to the plane of the strip. The strip according to the invention must be preferably used for the reinforcement of vehicle tires the reinforcement plies of which have at the meridian plane a radius of curvature of at least 1500 mm. Such strip can be in the form of a continuous long strip that is, or can be wound on a spool, or in the form of one or more separate ends of a length which preferably ranges in the order of magnitude of about 30 cm, e.g. in the range from 15 cm to 50 cm.
The mention that the strips are of the type that are adapted for the reinforcement of the belt of rubber vehicle tires does not limit its possible use in other applications such as the reinforcement of elastomeric articles in general. The mention means only that the strips have the necessary characteristics for such use, which are: a steel cross-section of the order of magnitude ranging between 0.05 mm 2 and 2 mm 2 , preferably in the range between, 0.150 mm 2 and 1 mm 2 , a tensile strength of the reinforcing steel of more than 2200 N/mm 2 , preferably more than 2500 N/mm 2 , an elongation at break of more than 1.5%, the reinforcing steel being covered with a rubber adherable coating, such as e.g. a metallic coating of brass.
It is already known, e.g. from U.S. Pat. No. 3,794,097, to form the belt ply of rubber vehicle tires, by laying short ends of nearly rectangular steel strips, instead of conventional steel cord, in a parallel disposition side by side with interstices between adjacent strips, filled with rubber.
A first advantage with respect to the use of conventional steel cords is, that the same amount of reinforcing steel can be laid in a thinner layer so as to obtain thinner and lighter plies. A second and important advantage is, that the strips have a much higher bending stiffness in the plane of the belt, and this reduces the deformation and heat generation under alternating shearing stresses in that plane, whilst maintaining good flexibility in any plane perpendicular to the belt.
The existing steel strips present however the important drawback, with respect to the use of conventional steel cord, of poor mechanical properties, especially tensile strength and fatigue endurance, due to the method in which they have to be made. Known methods are: slitting steel sheet or flat rolling of round wire. Slitting steel sheet produces sharp edges where stresses and fatigue crack initiation are concentrated. Flat cold rolling of round wire doesnot yield a high tensile strength level, because the rolling must be stopped far before such high level is reached in order to keep sufficient ductility for the subsequent rolling operation, in which the tensile strength level drops again. Due to the fact that in general the obtained fatigue resistance will be about 33% of the obtainable tensile strength, and that the strip in general shows some delamination bursts due to rolling, it will be difficult to reach a fatigue resistance of 600 Newton/mm 2 , whereas the new obtainable fatigue resistance of conventional high-tensile steel cord lies about twice this amount.
Attempts have been made to improve the mechanical properties of the steel strips by the use of an appropriate heat treatment, such as disclosed in U.S. Pat. No. 4,017,338 and 4,142,920. This results however into additional manufacturing costs and the mechanical properties as disclosed are still far from those of conventional steel cord. Among other things, the delamination bursts can indeed not be repaired by any heat treatment.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a reinforcing strip avoiding these drawbacks whilst still maintaining as much as possible the above-mentioned advantages of steel strip.
In accordance with the present invention there is provided a tire belt reinforcing strip and method of making same. The tire belt reinforcing strip of the invention has a significantly higher bending stiffness in the plane of the strip than in the longitudinal plane perpendicular thereto. The strip is in the form of a bundle of steel wires, preferably having flattened sides, extending side by side in one plane when the bundle is in a free straight position. Adjacent wires contact with each other along the flattened sides and are bound to each other to such an extent that the strip presents, in the plane of the strip, a significant excess of bending stiffness above the sum of the bending stiffness of the individual wires in the same plane; the steel cross section being between 0.05 mm 2 and 2 mm 2 with a tensile strength above 2200 N/mm 2 and an elongation at break above 1.5%.
The method in accordance with the invention is designed to provide a significantly higher bending stiffness to a tire belt reinforcing strip in a plane of the strip than in a longitudinal plane perpendicular thereto. The method comprises arranging a plurality of strands of wire-like material together in longitudinal, side by side, parallel relation so as to form a strip. A wire-like wrapping material is provided and is wrapped around the strip in intimate contact therewith under pressure to tightly wrap the strip so that the position of the strands comprising the strip is not substantially changed outside the plane of the strip.
In order to maintain these advantages as much as possible, the reinforcement will still be in the form of a strip having a significantly higher bending stiffness (i.e., at least twice) in the plane of the strip than in the axial plane perpendicular thereto. But the invention is characterized by the fact that the strip is in the form of a bundle of steel wires, extending side by side, in one plane when the bundle is in free straight position, adjacent wires being in contact with each other along the length and bound to each other to such extent that the strip presents, in the plane of strip, a significant excess of bending stiffness above the sum of the bending stiffnesses of the individual wires in the same plane. By "significant excess" is meant that the excess be at least one, preferably more than four times the bending stiffness of the individual wires in the plane of the strip.
For parallel wires which are loosely bound adjacent to each other (such as is the case in the European patent application with publication No. 0043563, it is known that the bending stiffness in the plane of the strip is equal to the sum of the bending stiffnesses of the individual wires in that plane, and that there is no significant excess above said sum. In the invention however, the wires are disposed side by side in a line contact with each other and so tied or bound together, that a significant excess is obtained, so that advantage can be taken of the strip-form.
The invention consists in fact in subdividing the breadth of the rectangular steel strip of the prior art, which is difficult to make with good properties, into a number of separate sections, each represented by a wire having a cross-sectional shape which is adapted for manufacturing by wire drawing, in which the whole technology of prior art wire drawing is available for obtaining more optimal mechanical properties, such as a tensile strength above 2750 N/mm 2 and a fatigue resistance above 900 N/mm 2 , preferably above 3000 N/mm 2 and 1000 N/mm 2 respectively. The number of wires is preferably 4 to 7. Round wires are preferred because the drawing and positioning of round wires puts the least problems, although other shapes are not excluded, in so far as their cross-section is adapted for wire drawing. The diameter of each wire is preferably in the range of 0.15-0.40 mm. Round wires have the further advantage with respect to steel strips that, for a same volume of steel, there is a greater steel surface available for the adherence of steel to the rubber matrix or elastomeric composition that it has to reinforce.
In order to apply the invention, it is however not sufficient to merely subdivide the breadth of a steel strip into a number of separate sections, each represented by a wire. If these wires, disposed in parallel in one plane, are loosely bound to each other so as to allow free movement between them, the whole would not act as a strip in the sense as to produce a higher bending stiffness in the plane of the strip. The stiffness would be the sum of the stiffnesses of the individual wires, whether they are disposed in a flat or in a round bundle. It is necessary that the adjacent wires are bound to each other, in a more or less yieldable way, but still so that the wires can interact so as to present in the plane of the strip, a significantly higher bending stiffness than the sum of the bending stiffnesses, in the same plane, of the individual wires.
The wires can be bound together e.g. by a wrapping wire, tightly wound around the flat bundle with a short pitch of preferably 1 to 4 times the breadth of the strip, so as to provide sufficient friction resistance between adjacent wires in order to raise the bending stiffness in the plane of the strip. This friction resistance can be improved, if desired, by providing a larger contact surface between adjacent wires instead of the line contact of perfectly round wires. The wrapping wire will preferably be a metallic wire of high tensile strength (e.g. above 2000 N/mm 2 in order to have a minimum diameter for this wire, e.g. not more than 70% of the thickness of the parallel wires, so that the thickness dimension of the strip can be kept as low as possible) but this wrapping wire, due to the short pitch with which it is wound around the strip, doesnot participate to the tensile strength of the strip.
The parallel wires can also be bound together by other mechanical binding means. But it is also possible to bind them together by a chemical adhesive, in so far as this adhesive does not harm the bond of the strip to rubber and in so far the shearing modulus of the chemical adhesive is greater than 2.5 MN/m 2 (Meganewton per square meter). The latter property is necessary in order to provide a real bound between the adjacent wires. For comparison: the shearing modulus of rubber that is conventionally used in the belt of vehicle tires, is less than 1.7 MN/m 2 ; such rubber should only provide a loose bound between the adjacent wires. However, rubbers having a shearing modulus greater than 2.5 MN/m 2 may also provide a real bound between the adjacent wires. The mechanical and chemical binding means can be combined and the whole presents itself either as a strip of infinite length which can be, or is wound on a spool, or as a number of separate strips with definite length.
The wires used for the reinforcing strip are preferably wires of the same kind as used for conventional steel cord, i.e. of the same steel composition, metallographic structure and physical characteristics due to the processing. This means a drawn pearlitic structure of a tensile strength of at least 2750 N/mm 2 , preferably at least 2325 -1130 log d Newton/mm 2 (d being the diameter of the wire in mm) and an elongation at break of more than 1.5%, and a composition in which the carbon, manganese and silicon are present in the ranges going respectively from 0.6 to 1% (preferably 0.7 to 0.9%), from 0.2 to 0.8%, and from 0.1 to 0.4%. The drawn structure can be recognized by the uniform hardness over the cross-sectional surface (i.e. a fluctuation of the Vickers hardness of maximum 10%). In order to reach a fatigue resistance value (as measured by the Hunter fatigue test) of at least 33% of the value of the tensile strength, the drawn wires can be processed by alternating bendings in the same way as disclosed in the French laid open application No. 82-01565. Oythr types of wire, processed to suitable properties can be used, such as drawn wire which is heat treated afterwards into tempered martensite as disclosed in U.S. Pat. No. 4,106,957.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now further be explained with reference to the accompanying drawings in which
FIG. 1 shows a front view of a strip according to the invention
FIG. 2 shows a cross-sectional view of the same strip
FIG. 3 shows a wrapping machine, adapted for making such strip
FIG. 4 shows a cross-sectional view of another type of strip according to the invention
FIG. 5 shows a cross-sectional view of a type of strip with non-round wires.
FIG. 6 shows a set-up of a three point bending test.
FIG. 7 shows a force versus displacement diagram obtained with a three point bending test.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a view of four round steel wires 1 of 0.25 mm diameter and a tensile strength of 3150 Newton/mm 2 , laid in parallel, side by side in the plane of the drawing and making a line contact with each other, so as to form a strip. A wrapping wire 2 of 0.15 mm is tightly wound around the strip with a pitch of about three times the breadth b of the strip. FIG. 2 shows a transverse cross-section of the same strip. The fact that the wrapping wire is tightly wound around the strip makes that this wire 2 must make a sharp bend around the edge 3 when passing from one side to the other side of the strip, and that, when making the bend, the wire 2 must keep in firm contact with the edge. This can be obtained by taking during manufacturing a specific precautionary measure, as schematically shown in FIG. 3, in order not to finish with a loose wrapping.
FIG. 3 shows schematically a wrapping machine in which four round wires 1 arrive in the sense of the arrow, side by side in a plane perpendicular to the drawing, so that only one wire is seen. The wrapping machine comprises a fixed frame 5 in which a rotatable axle 6 is mounted by means of bearings 7. This axle is driven into rotation by a gearing (only partly shown in 13). The axle 6 is axially traversed by a central bore. The four wires 1 traverse the axle 6 through the bore from left to right. At the right side, the axle 6 tapers into a point 8 and the four wires 1 emerge at this point. The wrapping machine further comprises a bobbin 9, mounted on the axle 6 for rotation together with said axle. This bobbin comprises the 0.15 mm wrapping wire 2, which is drawn over the flange 10 of the bobbin by means of flier arm 11. This arm 11 is rotatably mounted, by means of bearing 12, on a bush 15, which is removably fixed on the axle 6, and rotates together with said axle. The flier arm 11 can consequently rotate with respect to the bobbin 9, but this rotation is braked by means of brake 16 which is laterally pressed to the left against the flier 11, by means of a spring 18, of which the pressure is adjustable by means of the nut 17, which engages with a screwthread 19 on the bush 15. In this way an adjustable tension is created in the wrapping wire 2 on its way to the point where it joins the four parallel wires 1.
It is important that, at the point where the wrapping wire 2 joins the four wires 1, these four wires with the joining wrapping wire pass between two pressure rollers 20 and 21, so that the wrapping of the wire 2 occurs under the pressure of the rollers. When the rollers are positioned after the joining point, the wrapping is not sufficiently tight, even with a strong tension in the wrapping wire on its way towards the joining point. In order to avoid that the four parallel wires 1 would change position outside their plane, the point, where these wires emerge from the bore in the axle 6, is brought as near as possible (e.g. not more than 10 times the breadth of the strip) to the joining point of the wrapping wire between the rollers 20 and 21, and this is the reason why the rotating axle 6 tapers into a point.
The parallel wires 1 of the strip must not necessarily be bound together by a wrapping wire. They can be bound by embedding them in a chemical adhesive 22 (FIG. 4), but still in such a way that the wires make a frictional contact with each other. In order to increase the friction, the parts 23 where the wires make contact with each other can be flattened (FIG. 5). This can be done by slightly rolling the strip of wires 1 (FIG. 3) before entering the rotating axle 6.
The table hereunder compares, by way of example, the stiffness of four samples. Sample A is a rolled steel strip with rectangular cross-section of 0.25 mm by 1 mm and with a tensile strength of 2556 N/mm 2 . Sample B is an open cord construction consisting of 4 round wires having a diameter of 0.25 mm. Two wires are twisted around the other two wires, the latter being untwisted and parallel to each other. This cord has a tensile strength of 2700 N/mm 2 . Sample C is a theoretical example of 4 parallel round wires of 0.25 mm diameter in a same plane, making line contact with each other, and 100% fixed to each other along the line contacts. This sample is taken for having an idea of the maximum obtainable stiffness in the plane of the strip. Sample D is a sample according to the invention of 4 parallel round wires of 0.25 mm and a tensile strength of 3150 N/mm 2 , with a wrapping wire of 0.15 mm diameter, tightly wound around the bundle, with a pitch of 3.52 mm, manufactured according to the method given hereinabove.
The stiffness, as known, is the resistance to bending, i.e. the elasticity modulus E multiplied by the momentum of inertia I of the cross-section around the neutral plane.
According as the stiffness is measured for a bending in the plane of the strip or in a longitudinal plane perpendicular to the plane of the strip, the stiffness is called the "lateral" or the "radial" stiffness. For samples A and C, the theorical stiffness can be calculate, because for a rectangle, the momentum of inertia is bh 3 /12 (b being the dimension of the rectangle in the direction of the neutral line and h the dimension perpendicular thereto), and for a circle this momentum is equal to πd 2 /64. The modulus elasticity E of steel is assumed to be 200.000 N/mm 2 . The results of the calculations are given in the table.
For samples A, B and D, the stiffness can be measured with a three point bending test. A tensile testing machine in accordance with ASTM E4 and equipped with a compression cell is used. FIG. 6 illustrates the set-up of a three-point-bending-test. Two supports 24 at an interdistance l bear two rollers 25. The sample 26 is put on the rollers 25. A force by a stylus 27 causes a displacement x of the sample 26. A force versus displacement diagram is recorded during the test. An example of such a diagram is shown in FIG. 7. The force P forms the ordinate, the displacement x the abscissa. 28 represents the first loading and 29 the second loading. The total displacement is called W. Following points are determined on the diagram: X1 at a distance 0.3 W from 0, X2 at a distance 0.6 W from 0; P1 and P2, the ordinates corresponding to the abscissa X1 resp. X2. The stiffness is then calculated as follows: ##EQU1##
Further details about the three point bending test may be found in the paper by Bourgois L., "Survey of Mechanical Properties of Steel Cord and related test methods" in Tire Reinforcement and Tire Performance, ASTM STP 694, R. A. Fleming and D. F. Livingston, Eds. American Society for Testing and Materials, 1979, pp.19-46.
However, the three point bending test as such is not suited to measure directly the lateral stiffness of an elongate sample, i.e. a sample with a different radial and lateral stiffness. This is so, because the elongate sample would overturn during the measurement.
In order to avoid this unstability, four elongate samples, in this case four samples D, are embedded in a small rubber beam with a rectangular cross-section having a length of about 6 mm and a height of about 2.6 mm. The planes of the four samples D must be parallel to the height of the cross-section of the rubber beam. The rubber beam is put on the rollers 25, the short axis (height) of its cross-section being vertical, the long axis (length) being horizontal. The three point bending test is then carried out on the rubber beam in the conventional manner. In this way a stiffness of 2001 Nmm 2 for each sample D. However, this value of the stiffness is overestimated because of the influence of rubber. When four samples B are also embedded in the same way in such a rubber beam, then lateral stiffness of 732 Nmm 2 is obtained for the samples, while the real lateral stiffness of sample B is equal to the radial stiffness of sample B and is about 238 Nmm 2 , thus an overestimation with a ratio of 732/238=3.1.
Division of the measured stiffness of sample D (2001) by 3.1 eliminates the influence of rubber and gives 651 N/mm 2 as a result for the lateral stiffness of sample D.
The invention is not limited to a bundle of completely straight steel wires. These wires can be undulated, either in the plane of the strip (adjacent wires still being in contact with each other along their length, which needs a same wavelength), or outside the plane of the strip. In the latter case it is interesting to have parallel straight wires, which make a short undulation upwards out of the general plane of the strip at the locations where the wrapping wire passes under the wire, and a short undulation downwards at the location where the wrapping wire passes over the longitudinally running wire. In such a way, when short cut ends of such strip are laid in parallel for forming a belt ply for rubber tires, such belt ply can be significantly thinner.
TABLE__________________________________________________________________________ Theoretical Stiffness (Nmm.sup.2) Measured Stiffness (Nmm.sup.2) radial lateral lat/rad radial lateral lat/rad__________________________________________________________________________A. 1.0 × 0.25 260 4167 16 382 4513 11.81 rectangleB. 2 + 2 × 0.25 1 238 238 1 open cord 732 in rubberC. 4 × 0.25 153 3068 20 strip 100% tiedD. 4 × 0.25 + 288 2001 2.26 1 × 0.15/3.52 ↓ (*) strip 651__________________________________________________________________________ (*) conversion ratio = 732/238 = 3.1
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A reinforcing strip, and method of making same, specifically adapted for use in reinforcing plies in the belt of rubber tires. The strip comprises a number, preferably 4 to 7, of parallel wires, tightly bound together by a wrapping wire or a binder. This strip form allows to combine the advantages of steel strip, i.e. high lateral and low radial stiffness and thinner piles, with those of conventional steel cord, i.e. high tensile strength and fatigure resistance.
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FIELD OF THE INVENTION
The present invention is in the field of human medicine, particularly in the treatment of obesity and disorders associated with obesity. Most specifically the invention relates to anti-obesity proteins that when administered to a patient regulate fat tissue.
BACKGROUND OF THE INVENTION
Obesity, and especially upper body obesity, is a common and very serious public health problem in the United States and throughout the world. According to recent statistics, more than 25% of the United States population and 27% of the Canadian population are over weight. Kuczmarski, Amer. J. of Clin. Nut. 55: 495S-502S (1992); Reeder et. al., Can. Med. Ass. J., 23:226-233 (1992). Upper body obesity is the strongest risk factor known for type II diabetes mellitus, and is a strong risk factor for cardiovascular disease and cancer as well. Recent estimates for the medical cost of obesity are $150,000,000,000 world wide. The problem has become serious enough that the surgeon general has begun an initiative to combat the ever increasing adiposity rampant in American society.
Much of this obesity induced pathology can be attributed to the strong association with dyslipidemia, hypertension, and insulin resistance. Many studies have demonstrated that reduction in obesity by diet and exercise reduces these risk factors dramatically. Unfortunately these treatments are largely unsuccessful with a failure rate reaching 95%. This failure may be due to the fact that the condition is strongly associated with genetically inherited factors that contribute to increased appetite, preference for highly caloric foods, reduced physical activity, and increased lipogenic metabolism. This indicates that people inheriting these genetic traits are prone to becoming obese regardless of their efforts to combat the condition. Therefore, a new pharmacological agent that can correct this adiposity handicap and allow the physician to successfully treat obese patients in spite of their genetic inheritance is needed.
The ob/ob mouse is a model of obesity and diabetes that is known to carry an autosomal recessive trait linked to a mutation in the sixth chromosome. Recently, Yiying Zhang and co-workers published the positional cloning of the mouse gene linked with this condition. Yiying Zhang et al. Nature 372: 425-32 (1994). This report disclosed a gene coding for a 167 amino acid protein with a 21 amino acid signal peptide that is exclusively expressed in adipose tissue. The report continues to disclose that a mutation resulting in the conversion of a codon for arginine at position 105 to a stop codon results in the expression of a truncated protein, which presumably is inactive.
Physiologist have postulated for years that, when a mammal overeats, the resulting excess fat signals to the brain that the body is obese which, in turn, causes the body to eat less and burn more fuel. G. R. Hervey, Nature 227: 629-631 (1969). This "feedback" model is supported by parabiotic experiments, which implicate a circulating hormone controlling adiposity. Based on this model, the protein, which is apparently encoded by the ob gene, is now speculated to be an adiposity regulating hormone.
Pharmacological agents which are biologically active and mimic the activity of this protein are useful to help patients regulate their appetite and metabolism and thereby control their adiposity. Until the present invention, such a pharmacological agent was unknown.
The present invention provides biologically active anti-obesity proteins. Such agents therefore allow patients to overcome their obesity handicap and live normal lives with a more normalized risk for type II diabetes, cardiovascular disease and cancer.
SUMMARY OF INVENTION
The present invention is directed to a biologically active anti-obesity protein of the Formula (I): ##STR1## wherein: Xaa at position 13 is Ile, Leu, Met or methionine sulfoxide;
Xaa at position 15 is Gln or Glu;
Xaa at position 21 is Gln or Glu;
Xaa at position 22 is Gln or Glu;
Xaa at position 27 is Ile, Leu, Met or methionine sulfoxide;
Xaa at position 31 is Asn, Asp or Gln;
Xaa at position 34 is Gln or Glu;
Xaa at position 37 is Asn, Asp or Gln;
Xaa at position 41 is Asn, Asp or Gln;
Xaa at position 59 is Trp or Gln;
Xaa at position 89 is Gln or Glu;
Xaa at position 93 is Gln or Glu;
Xaa at position 95 is Ile, Leu, Met or methionine sulfoxide;
Xaa at position 97 is Trp or Gln; and
Xaa at position 98 is Gln or Glu.
The invention further provides a method of treating obesity, which comprises administering to a mammal in need thereof a protein of the Formula (I).
The invention further provides a pharmaceutical formulation, which comprises a protein of the Formula (I) together with one or more pharmaceutical acceptable diluents, carriers or excipients therefor.
DETAILED DESCRIPTION
As noted above the present invention provides a protein of the Formula (I): ##STR2## wherein: Xaa at position 13 is Ile, Leu, Met or methionine sulfoxide;
Xaa at position 15 is Gln or Glu;
Xaa at position 21 is Gln or Glu;
Xaa at position 22 is Gln or Glu;
Xaa at position 27 is Ile, Leu, Met or methionine sulfoxide;
Xaa at position 31 is Asn, Asp or Gln;
Xaa at position 34 is Gln or Glu;
Xaa at position 37 is Asn, Asp or Gln;
Xaa at position 41 is Asn, Asp or Gln;
Xaa at position 59 is Trp or Gln;
Xaa at position 89 is Gln or Glu;
Xaa at position 93 is Gln or Glu;
Xaa at position 95 is Ile, Leu, Met or methionine sulfoxide;
Xaa at position 97 is Trp or Gln; and
Xaa at position 98 is Gln or Glu.
The preferred proteins of the present invention are those of Formula (I) wherein:
Xaa at position 13 is Met;
Xaa at position 15 is Gln;
Xaa at position 21 is Gln;
Xaa at position 22 is Gln;
Xaa at position 27 is Met;
Xaa at position 31 is Asn;
Xaa at position 34 is Gln;
Xaa at position 37 is Asn;
Xaa at position 41 is Asn;
Xaa at position 59 is Trp;
Xaa at position 89 is Gln;
Xaa at position 93 is Gln;
Xaa at position 95 is Met;
Xaa at position 97 is Trp; and
Xaa at position 98 is Gln.
The amino acids abbreviations are accepted by the United States Patent and Trademark Office as set forth in 37 C.F.R. §1.822 (b)(2) (1993). One skilled in the art would recognize that certain amino acids are prone to rearrangement. For example, Asp may rearrange to aspartimide and isoasparigine as described in I. Schon et al., Int. J. Peptide Protein Res. 14:485-94 (1979) and references cited therein. These rearrangement derivatives are included within the scope of the present invention. Unless otherwise indicated the amino acids are in the L configuration.
For purposes of the present invention, as disclosed and claimed herein, the following terms and abbreviations are defined as follows:
Base pair (bp)--refers to DNA or RNA. The abbreviations A,C,G, and T correspond to the 5'-monophosphate forms of the nucleotides (deoxy)adenine, (deoxy)cytidine, (deoxy)guanine, and (deoxy)thymine, respectively, when they occur in DNA molecules. The abbreviations U,C,G, and T correspond to the 5'-monophosphate forms of the nucleosides uracil, cytidine, guanine, and thymine, respectively when they occur in RNA molecules. In double stranded DNA, base pair may refer to a partnership of A with T or C with G. In a DNA/RNA heteroduplex, base pair may refer to a partnership of T with U or C with G.
Chelating Peptide--An amino acid sequence capable of complexing with a multivalent metal ion.
DNA--Deoyxribonucleic acid.
EDTA--an abbreviation for ethylenediamine tetraacetic acid.
ED 50 --an abbreviation for half-maximal value.
FAB-MS--an abbreviation for fast atom bombardment mass spectrometry.
Immunoreactive Protein(s)--a term used to collectively describe antibodies, fragments of antibodies capable of binding antigens of a similar nature as the parent antibody molecule from which they are derived, and single chain polypeptide binding molecules as described in PCT Application No. PCT/US 87/02208, International Publication No. WO 88/01649.
mRNA--messenger RNA.
MWCO--an abbreviation for molecular weight cut-off.
Plasmid--an extrachromosomal self-replicating genetic element.
PMSF--an abbreviation for phenylmethylsulfonyl fluoride.
Reading frame--the nucleotide sequence from which translation occurs "read" in triplets by the translational apparatus of tRNA, ribosomes and associated factors, each triplet corresponding to a particular amino acid. Because each triplet is distinct and of the same length, the coding sequence must be a multiple of three. A base pair insertion or deletion (termed a frameshift mutation) may result in two different proteins being coded for by the same DNA segment. To insure against this, the triplet codons corresponding to the desired polypeptide must be aligned in multiples of three from the initiation codon, i.e. the correct "reading frame" must be maintained. In the creation of fusion proteins containing a chelating peptide, the reading frame of the DNA sequence encoding the structural protein must be maintained in the DNA sequence encoding the chelating peptide.
Recombinant DNA Cloning Vector--any autonomously replicating agent including, but not limited to, plasmids and phages, comprising a DNA molecule to which one or more additional DNA segments can or have been added.
Recombinant DNA Expression Vector--any recombinant DNA cloning vector in which a promoter has been incorporated.
Replicon--A DNA sequence that controls and allows for autonomous replication of a plasmid or other vector.
RNA--ribonucleic acid.
RP-HPLC--an abbreviation for reversed-phase high performance liquid chromatography.
Transcription--the process whereby information contained in a nucleotide sequence of DNA is transferred to a complementary RNA sequence.
Translation--the process whereby the genetic information of messenger RNA is used to specify and direct the synthesis of a polypeptide chain.
Tris--an abbreviation for tris(hydroxymethyl)-aminomethane.
Treating--describes the management and care of a patient for the purpose of combating the disease, condition, or disorder and includes the administration of a compound of present invention to prevent the onset of the symptoms or complications, alleviating the symptoms or complications, or eliminating the disease, condition, or disorder. Treating obesity therefor includes the inhibition of food intake, the inhibition of weight gain, and inducing weight loss in patients in need thereof.
Vector--a replicon used for the transformation of cells in gene manipulation bearing polynucleotide sequences corresponding to appropriate protein molecules which, when combined with appropriate control sequences, confer specific properties on the host cell to be transformed. Plasmids, viruses, and bacteriophage are suitable vectors, since they are replicons in their own right. Artificial vectors are constructed by cutting and joining DNA molecules from different sources using restriction enzymes and ligases. Vectors include Recombinant DNA cloning vectors and Recombinant DNA expression vectors.
X-gal--an abbreviation for 5-bromo-4-chloro-3-idolyl beta-D-galactoside.
SEQ ID NO: 1 refers to the sequence set forth in the sequence listing and means an anti-obesity protein of the formula: ##STR3## wherein: Xaa at position 13 is Ile, Leu, Met or methionine sulfoxide;
Xaa at position 15 is Gln or Glu;
Xaa at position 21 is Gln or Glu;
Xaa at position 22 is Gln or Glu;
Xaa at position 27 is Ile, Leu, Met or methionine sulfoxide;
Xaa at position 31 is Asn, Asp or Gln;
Xaa at position 34 is Gln or Glu;
Xaa at position 37 is Asn, Asp or Gln;
Xaa at position 41 is Asn, Asp or Gln;
Xaa at position 59 is Trp or Gln;
Xaa at position 89 is Gln or Glu;
Xaa at position 93 is Gln or Glu;
Xaa at position 95 is Ile, Leu, Met or methionine sulfoxide;
Xaa at position 97 is Trp or Gln; and
Xaa at position 98 is Gln or Glu.
Yiying Zhang et al. in Nature 372:425-32 (December 1994) report the cloning of the murine obese (ob) mouse gene and present mouse DNA and the naturally occurring amino acid sequence of the obesity protein for the mouse and human. This protein is speculated to be a hormone that is secreted by fat cells and controls body weight.
The present invention provides biologically active proteins that provide effective treatment for obesity. Many of the claimed proteins offer additional advantages of stability, especially acid stability, and improved absorption characteristics.
The claimed proteins ordinarily are prepared by modification of the DNA encoding the claimed protein and thereafter expressing the DNA in recombinant cell culture. Techniques for making substitutional mutations at predetermined sites in DNA having a known sequence are well known, for example M13 primer mutagenesis. The mutations that might be made in the DNA encoding the present anti-obesity proteins must not place the sequence out of reading frame and preferably will not create complementary regions that could produce secondary mRNA structure. See DeBoer et al., EP 75,444A (1983).
The compounds of the present invention may be produced either by recombinant DNA technology or well known chemical procedures, such as solution or solid-phase peptide synthesis, or semi-synthesis in solution beginning with protein fragments coupled through conventional solution methods.
A. Solid Phase
The synthesis of the claimed protein may proceed by solid phase peptide synthesis or by recombinant methods. The principles of solid phase chemical synthesis of polypeptides are well known in the art and may be found in general texts in the area such as Dugas, H. and Penney, C., Bioorganic Chemistry Springer-Verlag, New York, pgs. 54-92 (1981). For example, peptides may be synthesized by solid-phase methodology utilizing an PE-Applied Biosystems 430A peptide synthesizer (commercially available from Applied Biosystems, Foster City, Calif.) and synthesis cycles supplied by Applied Biosystems. Boc amino acids and other reagents are commercially available from PE-Applied Biosystems and other chemical supply houses. Sequential Boc chemistry using double couple protocols are applied to the starting p-methyl benzhydryl amine resins for the production of C-terminal carboxamides. For the production of C-terminal acids, the corresponding PAM resin is used. Arginine, Asparagine, Glutamine, Histidine and Methionine are coupled using preformed hydroxy benzotriazole esters. The following side chain protection may be used:
Arg, Tosyl
Asp, cyclohexyl or benzyl
Cys, 4-methylbenzyl
Glu, cyclohexyl
His, benzyloxymethyl
Lys, 2-chlorobenzyloxycarbonyl
Met, sulfoxide
Ser, Benzyl
Thr, Benzyl
Trp, formyl
Tyr, 4-bromo carbobenzoxy
Boc deprotection may be accomplished with trifluoroacetic acid (TFA) in methylene chloride. Formyl removal from Trp is accomplished by treatment of the peptidyl resin with 20% piperidine in dimethylformamide for 60 minutes at 4° C. Met(O) can be reduced by treatment of the peptidyl resin with TFA/dimethylsulfide/conHCl (95/5/1) at 25° C. for 60 minutes. Following the above pre-treatments, the peptides may be further deprotected and cleaved from the resin with anhydrous hydrogen fluoride containing a mixture of 10% m-cresol or m-cresol/10% p-thiocresol or m-cresol/p-thiocresol/dimethylsulfide. Cleavage of the side chain protecting group(s) and of the peptide from the resin is carried out at zero degrees Centigrade or below, preferably -20° C. for thirty minutes followed by thirty minutes at 0° C. After removal of the HF, the peptide/resin is washed with ether. The peptide is extracted with glacial acetic acid and lyophilized. Purification is accomplished by reverse-phase C18 chromatography (Vydac) column in 0.1% TFA with a gradient of increasing acetonitrile concentration.
One skilled in the art recognizes that the solid phase synthesis could also be accomplished using the FMOC strategy and a TFA/scavenger cleavage mixture.
B. Recombinant Synthesis
The claimed proteins may also be produced by recombinant methods. Recombinant methods are preferred if a high yield is desired. The basic steps in the recombinant production of protein include:
a) construction of a synthetic or semi-synthetic (or isolation from natural sources) DNA encoding the claimed protein,
b) integrating the coding sequence into an expression vector in a manner suitable for the expression of the protein either alone or as a fusion protein,
c) transforming an appropriate eukaryotic or prokaryotic host cell with the expression vector, and
d) recovering and purifying the recombinantly produced protein.
2.a. Gene Construction
Synthetic genes, the in vitro or in vivo transcription and translation of which will result in the production of the protein may be constructed by techniques well known in the art. Owing to the natural degeneracy of the genetic code, the skilled artisan will recognize that a sizable yet definite number of DNA sequences may be constructed which encode the claimed proteins. In the preferred practice of the invention, synthesis is achieved by recombinant DNA technology.
Methodology of synthetic gene construction is well known in the art. For example, see Brown, et al. (1979) Methods in Enzymology, Academic Press, New York, Vol. 68, pgs. 109-151. The DNA sequence corresponding to the synthetic claimed protein gene may be generated using conventional DNA synthesizing apparatus such as the Applied Biosystems Model 380A or 380B DNA synthesizers (commercially available from Applied Biosystems, Inc., 850 Lincoln Center Drive, Foster City, Calif. 94404).
It may desirable in some applications to modify the coding sequence of the claimed protein so as to incorporate a convenient protease sensitive cleavage site, e.g., between the signal peptide and the structural protein facilitating the controlled excision of the signal peptide from the fusion protein construct.
The gene encoding the claimed protein may also be created by using polymerase chain reaction (PCR). The template can be a cDNA library (commercially available from CLONETECH or STRATAGENE) or mRNA isolated from human adipose tissue. Such methodologies are well known in the art Maniatis, et al. Molecular cloning: A Laboratory Manual, Cold Spring Harbor Press, Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y. (1989).
2.b. Direct expression or Fusion protein
The claimed protein may be made either by direct expression or as fusion protein comprising the claimed protein followed by enzymatic or chemical cleavage. A variety of peptidases (e.g. trypsin) which cleave a polypeptide at specific sites or digest the peptides from the amino or carboxy termini (e.g. diaminopeptidase) of the peptide chain are known. Furthermore, particular chemicals (e.g. cyanogen bromide) will cleave a polypeptide chain at specific sites. The skilled artisan will appreciate the modifications necessary to the amino acid sequence (and synthetic or semi-synthetic coding sequence if recombinant means are employed) to incorporate site-specific internal cleavage sites. See e.g., Carter P., Site Specific Proteolysis of Fusion Proteins, Ch. 13 in Protein Purification: From Molecular Mechanisms to Large Scale Processes, American Chemical Soc., Washington, D.C. (1990).
2.c. Vector Construction
Construction of suitable vectors containing the desired coding and control sequences employ standard ligation techniques. Isolated plasmids or DNA fragments are cleaved, tailored, and religated in the form desired to form the plasmids required.
To effect the translation of the desired protein, one inserts the engineered synthetic DNA sequence in any of a plethora of appropriate recombinant DNA expression vectors through the use of appropriate restriction endonucleases. The claimed protein is a relatively large protein. A synthetic coding sequence is designed to possess restriction endonuclease cleavage sites at either end of the transcript to facilitate isolation from and integration into these expression and amplification and expression plasmids. The isolated cDNA coding sequence may be readily modified by the use of synthetic linkers to facilitate the incorporation of this sequence into the desired cloning vectors by techniques well known in the art. The particular endonucleases employed will be dictated by the restriction endonuclease cleavage pattern of the parent expression vector to be employed. The choice of restriction sites are chosen so as to properly orient the coding sequence with control sequences to achieve proper in-frame reading and expression of the claimed protein.
In general, plasmid vectors containing promoters and control sequences which are derived from species compatible with the host cell are used with these hosts. The vector ordinarily carries a replication site as well as marker sequences which are capable of providing phenotypic selection in transformed cells. For example, E. coli is typically transformed using pBR322, a plasmid derived from an E. coli species (Bolivar, et al., Gene 2:95 (1977)). Plasmid pBR322 contains genes for ampicillin and tetracycline resistance and thus provides easy means for identifying transformed cells. The pBR322 plasmid, or other microbial plasmid must also contain or be modified to contain promoters and other control elements commonly used in recombinant DNA technology.
The desired coding sequence is inserted into an expression vector in the proper orientation to be transcribed from a promoter and ribosome binding site, both of which should be functional in the host cell in which the protein is to be expressed. An example of such an expression vector is a plasmid described in Belagaje et al., U.S. Pat. No. 5,304,493, the teachings of which are herein incorporated by reference. The gene encoding A-C-B proinsulin described in U.S. Pat. No. 5,304,493 can be removed from the plasmid pRB182 with restriction enzymes NdeI and BamHI. The genes encoding the protein of the present invention can be inserted into the plasmid backbone on a NdeI/BamHI restriction fragment cassette.
2.d. Procaryotic expression
In general, procaryotes are used for cloning of DNA sequences in constructing the vectors useful in the invention. For example, E. coli K12 strain 294 (ATCC No. 31446) is particularly useful. Other microbial strains which may be used include E, coli B and E. coli X1776 (ATCC No. 31537). These examples are illustrative rather than limiting.
Prokaryotes also are used for expression. The aforementioned strains, as well as E. coli W3110 (prototrophic, ATCC No. 27325), bacilli such as Bacillus subtilis, and other enterobacteriaceae such as Salmonella typhimurium or Serratia marcescans, and various pseudomonas species may be used. Promoters suitable for use with prokaryotic hosts include the β-lactamase (vector pGX2907 [ATCC 39344] contains the replicon and β-lactamase gene) and lactose promoter systems (Chang et al., Nature, 275:615 (1978); and Goeddel et al., Nature 281:544 (1979)), alkaline phosphatase, the tryptophan (trp) promoter system (vector pATH1 [ATCC 37695] is designed to facilitate expression of an open reading frame as a trpE fusion protein under control of the trp promoter) and hybrid promoters such as the tac promoter (isolatable from plasmid pDR540 ATCC-37282). However, other functional bacterial promoters, whose nucleotide sequences are generally known, enable one of skill in the art to ligate them to DNA encoding the protein using linkers or adaptors to supply any required restriction sites. Promoters for use in bacterial systems also will contain a Shine-Dalgarno sequence operably linked to the DNA encoding protein.
2.e. Eucaryotic expression
The protein may be recombinantly produced in eukaryotic expression systems. Preferred promoters controlling transcription in mammalian host cells may be obtained from various sources, for example, the genomes of viruses such as: polyoma, Simian Virus 40 (SV40), adenovirus, retroviruses, hepatitis-B virus and most preferably cytomegalovirus, or from heterologous mammalian promoters, e.g. β-actin promoter. The early and late promoters of the SV40 virus are conveniently obtained as an SV40 restriction fragment which also contains the SV40 viral origin of replication. Fiers, et al., Nature, 273:113 (1978). The entire SV40 genome may be obtained from plasmid pBRSV, ATCC 45019. The immediate early promoter of the human cytomegalovirus may be obtained from plasmid pCMBβ (ATCC 77177). Of course, promoters from the host cell or related species also are useful herein.
Transcription of a DNA encoding the claimed protein by higher eukaryotes is increased by inserting an enhancer sequence into the vector. Enhancers are cis-acting elements of DNA, usually about 10-300 bp, that act on a promoter to increase its transcription. Enhancers are relatively orientation and position independent having been found 5' (Laimins, L. et al., PNAS 78:993 (1981)) and 3' (Lusky, M. L., et al., Mol. Cell Bio. 3:1108 (1983)) to the transcription unit, within an intron (Banerji, J. L. et al., Cell 33:729 (1983)) as well as within the coding sequence itself (Osborne, T. F., et al., Mol. Cell Bio. 4:1293 (1984)). Many enhancer sequences are now known from mammalian genes (globin, RSV, SV40, EMC, elastase, albumin, a-fetoprotein and insulin). Typically, however, one will use an enhancer from a eukaryotic cell virus. Examples include the SV40 late enhancer, the cytomegalovirus early promoter enhancer, the polyoma enhancer on the late side of the replication origin, and adenovirus enhancers.
Expression vectors used in eukaryotic host cells (yeast, fungi, insect, plant, animal, human or nucleated cells from other multicellular organisms) will also contain sequences necessary for the termination of transcription which may affect mRNA expression. These regions are transcribed as polyadenylated segments in the untranslated portion of the mRNA encoding protein. The 3'untranslated regions also include transcription termination sites.
Expression vectors may contain a selection gene, also termed a selectable marker. Examples of suitable selectable markers for mammalian cells are dihydrofolate reductase (DHFR, which may be derived from the BglII/HindIII restriction fragment of pJOD-10 [ATCC 68815]), thymidine kinase (herpes simplex virus thymidine kinase is contained on the BamHI fragment of vP-5 clone [ATCC 2028]) or neomycin (G418) resistance genes (obtainable from pNN414 yeast artificial chromosome vector [ATCC 37682]). When such selectable markers are successfully transferred into a mammalian host cell, the transfected mammalian host cell can survive if placed under selective pressure. There are two widely used distinct categories of selective regimes. The first category is based on a cell's metabolism and the use of a mutant cell line which lacks the ability to grow without a supplemented media. Two examples are: CHO DHFR - cells (ATCC CRL-9096) and mouse LTK - cells (L-M(TK-) ATCC CCL-2.3). These cells lack the ability to grow without the addition of such nutrients as thymidine or hypoxanthine. Because these cells lack certain genes necessary for a complete nucleotide synthesis pathway, they cannot survive unless the missing nucleotides are provided in a supplemented media. An alternative to supplementing the media is to introduce an intact DHFR or TK gene into cells lacking the respective genes, thus altering their growth requirements. Individual cells which were not transformed with the DHFR or TK gene will not be capable of survival in nonsupplemented media.
The second category is dominant selection which refers to a selection scheme used in any cell type and does not require the use of a mutant cell line. These schemes typically use a drug to arrest growth of a host cell. Those cells which have a novel gene would express a protein conveying drug resistance and would survive the selection. Examples of such dominant selection use the drugs neomycin, Southern P. and Berg, P., J. Molec. Appl. Genet. 1:327 (1982), mycophenolic acid, Mulligan, R. C. and Berg, P. Science 209:1422 (1980), or hygromycin, Sugden, B. et al., Mol Cell. Biol. 5:410-413 (1985). The three examples given above employ bacterial genes under eukaryotic control to convey resistance to the appropriate drug G418 or neomycin (geneticin), xgpt (mycophenolic acid) or hygromycin, respectively.
A preferred vector for eucaryotic expression is pRc/CMV. pRc/CMV is commercially available from Invitrogen Corporation, 3985 Sorrento Valley Blvd., San Diego, Calif. 92121. To confirm correct sequences in plasmids constructed, the ligation mixtures are used to transform E. coli K12 strain DH5a (ATCC 31446) and successful transformants selected by antibiotic resistance where appropriate. Plasmids from the transformants are prepared, analyzed by restriction and/or sequence by the method of Messing, et al., Nucleic Acids Res. 9:309 (1981).
Host cells may be transformed with the expression vectors of this invention and cultured in conventional nutrient media modified as is appropriate for inducing promoters, selecting transformants or amplifying genes. The culture conditions, such as temperature, pH and the like, are those previously used with the host cell selected for expression, and will be apparent to the ordinarily skilled artisan. The techniques of transforming cells with the aforementioned vectors are well known in the art and may be found in such general references as Maniatis, et al., Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Press, Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y. (1989), or Current Protocols in Molecular Biology (1989) and supplements.
Preferred suitable host cells for expressing the vectors encoding the claimed proteins in higher eukaryotes include: African green monkey kidney line cell line transformed by SV40 (COS-7, ATCC CRL-1651); transformed human primary embryonal kidney cell line 293,(Graham, F. L. et al., J. Gen Virol. 36:59-72 (1977), Virology 77:319-329, Virology 86:10-21); baby hamster kidney cells (BHK-21(C-13), ATCC CCL-10, Virology 16:147 (1962)); chinese hamster ovary cells CHO-DHFR 31 (ATCC CRL-9096), mouse Sertoli cells (TM4, ATCC CRL-1715, Biol. Reprod. 23:243-250 (1980)); african green monkey kidney cells (VERO 76, ATCC CRL-1587); human cervical epitheloid carcinoma cells (HeLa, ATCC CCL-2); canine kidney cells (MDCK, ATCC CCL-34); buffalo rat liver cells (BRL 3A, ATCC CRL-1442); human diploid lung cells (WI-38, ATCC CCL-75); human hepatocellular carcinoma cells (Hep G2, ATCC HB-8065);and mouse mammary tumor cells (MMT 060562, ATCC CCL51).
2.f. Yeast expression
In addition to prokaryotes, eukaryotic microbes such as yeast cultures may also be used. Saccharomyces cerevisiae, or common baker's yeast is the most commonly used eukaryotic microorganism, although a number of other strains are commonly available. For expression in Saccharomyces, the plasmid YRp7, for example, (ATCC-40053, Stinchcomb, et al., Nature 282:39 (1979); Kingsman et al., Gene 7:141 (1979); Tschemper et al., Gene 10:157 (1980)) is commonly used. This plasmid already contains the trp gene which provides a selection marker for a mutant strain of yeast lacking the ability to grow in tryptophan, for example ATCC no. 44076 or PEP4-1 (Jones, Genetics 85:12 (1977)).
Suitable promoting sequences for use with yeast hosts include the promoters for 3-phosphoglycerate kinase (found on plasmid pAP12BD ATCC 53231 and described in U.S. Pat. No. 4,935,350, Jun. 19, 1990) or other glycolytic enzymes such as enolase (found on plasmid pAC1 ATCC 39532), glyceraldehyde-3phosphate dehydrogenase (derived from plasmid pHcGAPC1 ATCC 57090, 57091), zymomonas mobilis (U.S. Pat. No. 5,000,000 issued Mar. 19, 1991), hexokinase, pyruvate decarboxylase, phosphofructokinase, glucose-6-phosphate isomerase, 3-phosphoglycerate mutase, pyruvate kinase, triosephosphate isomerase, phosphoglucose isomerase, and glucokinase.
Other yeast promoters, which are inducible promoters having the additional advantage of transcription controlled by growth conditions, are the promoter regions for alcohol dehydrogenase 2, isocytochrome C, acid phosphatase, degradative enzymes associated with nitrogen metabolism, metallothionein (contained on plasmid vector pCL28XhoLHBPV ATCC 39475, U.S. Pat. No. 4,840,896), glyceraldehyde 3-phosphate dehydrogenase, and enzymes responsible for maltose and galactose (GAL1 found on plasmid pRY121 ATCC 37658) utilization. Suitable vectors and promoters for use in yeast expression are further described in R. Hitzeman et al., European Patent Publication No. 73,657A. Yeast enhancers such as the UAS Gal from Saccharomyces cerevisiae (found in conjunction with the CYC1 promoter on plasmid YEpsec--hI1beta ATCC 67024), also are advantageously used with yeast promoters.
The following examples are presented to further illustrate the preparation of the claimed proteins. The scope of the present invention is not to be construed as merely consisting of the following examples.
EXAMPLE 1
A DNA sequence encoding the following protein sequence: ##STR4## is obtained using standard PCR methodology. A forward primer (5'-GG GG CAT ATG AGG GTA CCT ATC CAG AAA GTC CAG GAT GAC AC)SEQ ID NO:2 and a reverse primer (5'-GG GG GGATC CTA TTA GCA CCC GGG AGA CAG GTC CAG CTG CCA CAA CAT)SEQ ID NO:3 is used to amplify sequences from a human fat cell library (commercially available from CLONETECH). The PCR product is cloned into PCR-Script (available from STRATAGENE) and sequenced.
EXAMPLE 2
Vector Construction
A plasmid containing the DNA sequence encoding the desired claimed protein is constructed to include NdeI and BamHI restriction sites. The plasmid carrying the cloned PCR product is digested with NdeI and BamHI restriction enzymes. The small ˜450bp fragment is gel-purified and ligated into the vector pRB182 from which the coding sequence for A-C-B proinsulin is deleted. The ligation products are transformed into E. coli DH10B (commercially available from GIBCO-BRL) and colonies growing on tryptone-yeast (DIFCO) plates supplemented with 10 μg/mL of tetracycline are analyzed. Plasmid DNA is isolated, digested with NdeI and BamHI and the resulting fragments are separated by agarose gel electrophoresis. Plasmids containing the expected˜450bp NdeI to BamHI fragment are kept. E. coli B BL21 (DE3) (commercially available from NOVOGEN) are transformed with this second plasmid expression suitable for culture for protein production.
The techniques of transforming cells with the aformentioned vectors are well known in the art and may be found in such general references as Maniatis, et al. (1988) Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Press, Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y. or Current Protocols in Molecular Biology (1989) and supplements. The techniques involved in the transformation of E. coli cells used in the preferred practice of the invention as exemplified herein are well known in the art. The precise conditions under which the transformed E. coli cells are cultured is dependent on the nature of the E. coli host cell line and the expression or cloning vectors employed. For example, vectors which incorporate thermoinducible promoter-operator regions, such as the c1857 thermoinducible lambda-phage promoter-operator region, require a temperature shift from about 30 to about 40 degrees C. in the culture conditions so as to induce protein synthesis.
In the preferred embodiment of the invention E. coli K12 RV308 cells are employed as host cells but numerous other cell lines are available such as, but not limited to, E. coli K12, L201, L687, L693, L507, L640, L641, L695, L814 (E. coli B). The transformed host cells are then plated on appropriate media under the selective pressure of the antibiotic corresponding to the resistance gene present on the expression plasmid. The cultures are then incubated for a time and temperature appropriate to the host cell line employed.
Proteins which are expressed in high-level bacterial expression systems characteristically aggregate in granules or inclusion bodies which contain high levels of the overexpressed protein. Kreuger et al., in Protein Folding, Gierasch and King, eds., pgs 136-142 (1990), American Association for the Advancement of Science Publication No. 89-18S, Washington, D.C. Such protein aggregates must be solubilized to provide further purification and isolation of the desired protein product. Id. A variety of techniques using strongly denaturing solutions such as guanidinium-HCl and/or weakly denaturing solutions such as dithiothreitol (DTT) are used to solubilize the proteins.
Gradual removal of the denaturing agents (often by dialysis) in a solution allows the denatured protein to assume its native conformation. The particular conditions for denaturation and folding are determined by the particular protein expression system and/or the protein in question.
Preferably, the present proteins are expressed as Met-Arg-SEQ ID NO:1 so that the expressed proteins may be readily converted to the claimed protein with Cathepsin C. The purification of proteins is by techniques known in the art and includes reverse phase chromatography, affinity chromatography, and size exclusion.
The claimed proteins contain two cysteine residues. Thus, a di-sulfide bond may be formed to stabilize the protein. The present invention includes proteins of the Formula (I) wherein the Cys at position 55 of SEQ ID NO:1 is crosslinked to Cys at position 105 of SEQ ID NO:1 as well as those proteins without such di-sulfide bonds.
In addition the proteins of the present invention may exist, particularly when formulated, as dimers, trimers, tetramers, and other multimers. Such multimers are included within the scope of the present invention.
The present invention provides a method for treating obesity. The method comprises administering to the organism an effective amount of anti-obesity protein in a dose between about 1 and 1000 μg/kg. A preferred dose is from about 10 to 100 μg/kg of active compound. A typical daily dose for an adult human is from about 0.5 to 100 mg. In practicing this method, compounds of the Formula (I) can be administered in a single daily dose or in multiple doses per day. The treatment regime may require administration over extended periods of time. The amount per administered dose or the total amount administered will be determined by the physician and depend on such factors as the nature and severity of the disease, the age and general health of the patient and the tolerance of the patient to the compound.
The instant invention further provides pharmaceutical formulations comprising compounds of the Formula (I). The proteins, preferably in the form of a pharmaceutically acceptable salt, can be formulated for nasal, bronchal, transdermal, or parenteral administration for the therapeutic or prophylactic treatment of obesity. For example, compounds of the Formula (I) can be admixed with conventional pharmaceutical carriers and excipients. The compositions comprising claimed proteins contain from about 0.1 to 90% by weight of the active protein, preferably in a soluble form, and more generally from about 10 to 30%.
For intravenous (IV) use, the protein is administered in commonly used intravenous fluid(s) and administered by infusion. Such fluids, for example, physiological saline, Ringer's solution or 5% dextrose solution can be used.
For intramuscular preparations, a sterile formulation, preferably a suitable soluble salt form of a protein of the Formula (I), for example the hydrochloride salt, can be dissolved and administered in a pharmaceutical diluent such as pyrogen-free water (distilled), physiological saline or 5% glucose solution. A suitable insoluble form of the compound may be prepared and administered as a suspension in an aqueous base or a pharmaceutically acceptable oil base, e.g. an ester of a long chain fatty acid such as ethyl oleate.
It may also be desirable to administer the compounds of Formula (I) intranasally. Formulations useful in the intranasal absorption of proteins are well known in the art. Nasal formulations comprise the protein and carboxyvinyl polymer preferably selected from the group comprising the acrylic acid series hydrophilic crosslinked polymer, e.g. carbopole 934, 940, 941 (Goodrich Co.). The polymer accelerates absorption of the protein, and gives suitable viscosity to prevent discharge from nose. Suitable content of the polymer is 0.05-2 weight %. By neutralisation of the polymer with basic substance, thickening effect is increased. The amount of active compound is commonly 0.1-10%. The nasal preparation may be in drop form, spraying applicator or aerosol form.
The ability of the present compounds to treat obesity is demonstrated in vivo as follows:
Biological Testing for Anti-obesity proteins
Parabiotic experiments suggest that a protein is released by peripheral adipose tissue and that the protein is able to control body weight gain in normal, as well as obese mice. Therefore, the most closely related biological test is to inject the test article by any of several routes of administration (e.g.i.v., s.c., i.p., or by minipump or cannula) and then to monitor food and water consumption, body weight gain, plasma chemistry or hormones (glucose, insulin, ACTH, corticosterone, GH, T4) over various time periods.
Suitable test animals include normal mice (ICR, etc.) and obese mice (ob/ob, Avy/a, KK-Ay, tubby, fat). The ob/ob mouse model of obesity and diabetes is generally accepted in the art as being indicative of the obesity condition. Controls for non-specific effects for these injections are done using vehicle with or without the active agent of similar composition in the same animal monitoring the same parameters or the active agent itself in animals that are thought to lack the receptor (db/db mice, fa/fa or cp/cp rats). Proteins demonstrating activity in these models will demonstrate similar activity in other mammals, particularly humans.
Since the target tissue is expected to be the hypothalamus where food intake and lipogenic state are regulated, a similar model is to inject the test article directly into the brain (e.g.i.c.v. injection via lateral or third ventricles, or directly into specific hypothalamic nuclei (e.g. arcuate, paraventricular, perifornical nuclei). The same parameters as above could be measured, or the release of neurotransmitters that are known to regulate feeding or metabolism could be monitored (e.g. NPY, galanin, norepinephrine, dopamine, β-endorphin release).
Similar studies are accomplished in vitro using isolated hypothalamic tissue in a perifusion or tissue bath system. In this situation, the release of neurotransmitters or electrophysiological changes is monitored.
The compounds are active in at least one of the above biological tests and are anti-obesity agents. As such, they are useful in treating obesity and those disorders implicated by obesity. However, the proteins are not only useful as therapeutic agents; one skilled in the art recognizes that the proteins are useful in the production of antibodies for diagnostic use and, as proteins, are useful as feed additives for animals. Furthermore, the compounds are useful for controlling weight for cosmetic purposes in mammals. A cosmetic purpose seeks to control the weight of a mammal to improve bodily appearance. The mammal is not necessarily obese. Such cosmetic use forms part of the present invention.
__________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 3(2) INFORMATION FOR SEQ ID NO:1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 105 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(ix) FEATURE: (A) NAME/KEY: Modified-site(B) LOCATION: 13(D) OTHER INFORMATION: /note="Xaa at position 13 is Ile,Leu, Met or methionine sulfoxide;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 15(D) OTHER INFORMATION: /note="Xaa at position 15 is Glnor Glu;"(ix) FEATURE: (A) NAME/KEY: Modified-site(B) LOCATION: 21(D) OTHER INFORMATION: /note="Xaa at position 21 is Glnor Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 22(D) OTHER INFORMATION: /note="Xaa at position 22 is Glnor Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 27(D) OTHER INFORMATION: /note="Xaa at position 27 is Ile,Leu, Met or methionine sulfoxide;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 31(D) OTHER INFORMATION: /note="Xaa at position 31 is AsnAsp or Gln;"(ix) FEATURE:(A) NAME/KEY: Modified-site (B) LOCATION: 34(D) OTHER INFORMATION: /note="Xaa at position 34 is Glnor Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 37(D) OTHER INFORMATION: /note="Xaa at position 37 is Asn,Asp or Gln;"(ix) FEATURE:(A) NAME/KEY: Modified-site (B) LOCATION: 41(D) OTHER INFORMATION: /note="Xaa at position 41 is Asn,Asp or Gln;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 59(D) OTHER INFORMATION: /note="Xaa at position 59 is Trpor Gln;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 89(D) OTHER INFORMATION: /note="Xaa at position 89 is Glnor Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 93(D) OTHER INFORMATION: /note="Xaa at position 93 is Glnor Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 95 (D) OTHER INFORMATION: /note="Xaa at position 95 is Ile,Leu, Met or methionine sulfoxide;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 97(D) OTHER INFORMATION: /note="Xaa at position 97 is Trpor Gln;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 98 (D) OTHER INFORMATION: /note="Xaa at position 98 is Glnor Glu."(xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:IleProGlyLeuHisProIleLeuThrLeuSerLysXaaAspXaaThr151015Le uAlaValTyrXaaXaaIleLeuThrSerXaaProSerArgXaaVal202530IleXaaIleSerXaaAspLeuGluXaaLeuArgAspLeuLeuHisVal 354045LeuAlaPheSerLysSerCysHisLeuProXaaAlaSerGlyLeuGlu505560ThrLeuAsp SerLeuGlyGlyValLeuGluAlaSerGlyTyrSerThr65707580GluValValAlaLeuSerArgLeuXaaGlySerLeuXaaAspXaaLeu 859095XaaXaaLeuAspLeuSerProGlyCys100105(2) INFORMATION FOR SEQ ID NO:2:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 42 base pairs (B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:GGGGCATATGAGGGTACCTATCCAGAAAGTCCAGGATGACAC42(2) INFORMATION FOR SEQ ID NO:3:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 48 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:GGGGGGATCCTATTAGCACCCGGGAGACAGGTCCAGCTGCCACAACAT48__________________________________________________________________________
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The present invention provides anti-obesity proteins, which when administered to a patient regulate fat tissue. Accordingly, such agents allow patients to overcome their obesity handicap and live normal lives with much reduced risk for type II diabetes, cardiovascular disease and cancer.
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FIELD OF THE INVENTION
This invention relates to arrangements for use in protecting vehicles, particularly armored fighting vehicles and other military vehicles, from incoming projectiles.
BACKGROUND OF THE INVENTION
It has been proposed to provide armored military vehicles with "explosive" active armor which is activated by the vehicle's defensive aids sensor suite on detection of an incoming missile. The detonation of a charge at or near the vehicle's outer surface produces a shower of fragments which, if correctly timed, will damage the incoming missile before it reaches the vehicle. If however the charge is detonated accidentally, the vehicle is likely to be damaged unnecessarily, and there is a risk of injury to any personnel in the vicinity of the vehicle.
Missiles and other ordnance may be directed towards a target using laser guidance, "laser guided ordnance" being the generic name for this family of weapon systems. These weapons have a laser seeking sensor device which is sensitive to laser radiation scattered by the target. The laser radiation is directed at the target from a distant laser designator which may be on the vehicle launching the laser guided ordnance, on a separate vehicle or on the ground, with a means of communicating with the weapon launching system to synchronize the attack. The illuminating laser radiation is formed into a narrow beam so that only the target is illuminated, and is in the form of a precisely timed pulse train. The laser seeking sensor or "seeker" is generally sensitive only to the laser wavelength in use and only reacts to laser pulse trains with the correct timing characteristics, and may use further discrimination techniques to minimize the susceptibility of the system to a range of decoy techniques.
There are two broad classes of laser guided ordnance. One class is bombs and missiles of the 225-900 kg (500-2000 lb) class, designed for use against large heavy fixed installations. The other class is laser guided missiles, typically used for anti-tank applications. For both classes of ordnance, a target is illuminated by a laser designator. Both types of ordnance are directed towards the scattered reflected laser radiation. Bombs follow a ballistic trajectory and will generally dive onto the target. The large warhead will detonate on or after impact and may cause damage even with a near miss. To protect a large installation against a bomb it is necessary to decoy the seeker sufficiently to cause the bomb to fall many meters from the point illuminated by the laser designator. On the other hand, laser guided anti-tank missiles generally follow a flat trajectory and will only damage the target seriously if they achieve a direct hit. To protect a vehicle, particularly a tank or other armored vehicle, against laser guided anti-tank missiles, it is therefore only necessary to cause the missile to deviate sufficiently to prevent a direct hit.
Existing laser repeater decoys illuminate a point near the target with a pulse train from a laser which is triggered by receipt of incoming laser pulses. The repeater pulse is arranged to go out very quickly after the received pulse so that timing circuits in the seeker are unable to discriminate against the decoy from the pulse interval. To minimize the time of flight difference between the real and decoy lasers, the decoy is usually thrown forward of the target towards the incoming threat. The laser energy of the decoy as seen by the seeker also needs to be stronger than the return from the real designating beam to ensure the seeker accepts the decoy rather than the real designator. Finally, if the decoy is placed too far from the real target, the seeker may not see it or may be able to determine that the decoy is not the correct target. In a prepared position the geometry and energy levels can be determined and a suitable decoy location selected. However, in the case of a mobile vehicle this is much more difficult, particularly since the vehicle will often position itself behind ground or vegetation cover which would block or attenuate the decoy signal to a missile seeker.
It is among the objects of embodiments of the present invention to provide an arrangement for protecting vehicles against incoming projectiles which does not require such precise timing as the existing active armor countermeasures described above, and which will not present a danger to personnel in the event of accidental activation.
It is among the objects of further embodiments of the present invention to provide an arrangement for implementing a laser decoy which will be effective in protecting vehicles against laser anti-tank missiles.
SUMMARY OF THE INVENTION
According to the present invention there is provided an arrangement for protecting a vehicle from incoming projectiles, the arrangement comprising an inflatable structure for mounting on a vehicle; and means for inflating the structure on detection of an incoming projectile such that the inflated structure extends from the vehicle.
This countermeasure or decoy arrangement will typically be linked to the vehicle's defensive aids sensor suite, which detects the presence of incoming missiles. This permits automatic deployment of the structure immediately a missile is detected. For certain embodiments, an incoming projectile may be detected indirectly, for example, by the detection of an incoming laser pulse from a laser designator associated with laser guided ordnance.
The use of an inflatable structure allows rapid deployment of the structure in the limited period between detection of a incoming projectile and the projectile reaching the vehicle. The technology to provide such rapid deployment is already widely available and in use in, for example, vehicle airbag inflation arrangements. Inflation of the structure may be achieved by one or both of detonation of sodium azide charge and release of high pressure gas. As the former tends to heat the structure and the latter tends to cool the structure, a combination of both inflation methods allows the thermal image of the inflated structure to be controlled.
In one embodiment the structure has the same or similar infra-red (IR) or radar reflectivity as the vehicle surface and this may be achieved by, for example, metallizing the surface of the structure or by including a reflective shield in the structure. Thus, for example, an incoming missile equipped with an active IR fuse will be prematurely triggered before reaching the optimum stand-off distance, thus reducing the damage to the vehicle.
In a further embodiment, the inflated structure may include rigid or semi-rigid elements, or may serve to erect a rigid or semi-rigid element, such as a solid plate. These elements may be utilized to trigger missiles with contact fusing systems, before the missile contacts the vehicle armor.
In another embodiment, the inflated structure may alter specific characteristics of the vehicle profile to deny target recognition by anti-tank guided weapons; such weapons are equipped with range finding optics which detonate the missile on detecting the specific optical signature produced as the missile flies over a tank, thus exploiting the relatively weak top armor. Specifically, the range-finding optics recognize the large ground to hull step change and the smaller hull to turret change, and these may be disguised or altered by appropriately configured structures.
In an embodiment for implementing a laser decoy, the inflatable structure is deployed on detection of an incoming designator pulse train and is inflated to extend upwardly above the roof of the vehicle. The surface of the inflated structure preferably bears a visual camouflage, matched to the vehicle. Most preferably, the surface of the inflated structure has high diffuse scattering characteristics at the laser designator wavelengths, currently around 1.06 microns. The arrangement may include a laser repeater which is triggered by incoming laser pulse trains to illuminate the inflated structure, scattering the energy from the laser repeater and thus providing a decoy above the vehicle. The incoming missile will tend to fly through the inflated structure which may collapse or shred under impact, or may act to destabilize the missile so that it topples and crashes close behind the vehicle, or may cause the missile fuse to detonate causing the missile to self-destruct. The radiation from the laser repeater may be directed upwardly into the interior of the inflated structure, towards the exterior of the inflated structure from elsewhere on the vehicle, or into a group of optical conductors, such as optical fibers, mounted on the inflatable structure and terminating at locations on the structure.
In another laser decoy embodiment, a first inflatable structure is provided for deflecting incoming laser energy from a designator and a second inflatable structure is provided for deployment above the vehicle for collecting the reflected radiation and scattering this radiation so that it may be detected by a missile seeker. Preferably, the first inflatable structure inflates to define a sloping skirt around the vehicle, and has high specular reflectivity and low diffuse reflectivity.
These embodiments may be provided individually or combined together.
The invention also relates to a vehicle provided with one or more arrangements as described above.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic side view of an arrangement for protecting an armored vehicle from incoming missiles in accordance with a first embodiment of the present invention;
FIG. 2 is a schematic side view of an arrangement for protecting an armored vehicle from incoming missiles in accordance with a second embodiment of the present invention; and
FIGS. 3 and 4 are schematic views of arrangements for protecting armored vehicle from incoming laser guided missiles in accordance with third and fourth embodiments of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Reference is first made to FIG. 1 of the drawings which illustrates an arrangement for protecting an armored vehicle, in this example a tank 10, from incoming proximity fusing missiles. Such missiles include active infra-red (IR) or radar fuses which are primed to detonate a few meters short of the target, to provide time for the explosion to develop and optimize penetration depth.
The arrangement includes one or more rapidly inflating airbags 12, 14 including material having the same IR and radar reflectivity as the tank 10. Thus, the active fuse on the incoming projectile will be prematurely triggered and armor penetration significantly reduced. The airbags 12, 14 are inflated, by respective inflation devices 13, 15, towards the incoming projectile and in this example the airbags and inflation devices are shown mounted on the tank turret 16. One of the illustrated airbags 12 is in the form of a simple cone, whereas the other airbag 14 is utilized to erect an IR or radar reflective shield 18.
Inflation of the airbags 12, 14 is cued by a sensor 19 in the defensive aids suite of the tank, and due to the short time interval between detection of an incoming missile and contact with the tank 10, the airbags 12, 14 are deployed rapidly and automatically immediately following missile detection.
Reference is now made to FIG. 2 of the drawings, which illustrates an arrangement in accordance with a second embodiment of the invention. This arrangement is intended to "disguise" the tank 20 from anti-tank guided weapons (ATGW) including range finding optics which recognize a tank profile as the weapon passes over the tank. Such missiles are intended to detonate above the vehicle, to exploit the relatively weak top armor. Due to the altered profile of the tank, the weapon will thus pass over the tank 20 without detonating, such that this arrangement is particularly useful for vehicles protected by light armor.
In the illustrated example airbags 22, 23 extend outwardly and downwardly from the front and rear of the tank to disguise the large ground to hull step change. Further airbags 22a, 23a may also be provided to disguise the smaller hull to turret step change.
As with the first described embodiment, the airbags 22, 23 are inflated immediately an incoming missile is detected by the defensive aids suite of the tank 24.
From the above-described embodiments it will be apparent to those of skill in the art that the timing of the deployment of the described countermeasures is not as critical as in active armor countermeasures. Further, accidental activation of the airbag inflation means presents minimal risk to personnel and will not result in damage to the vehicle.
Reference is now made to FIG. 3 of the drawings which is a schematic illustration of an arrangement for protecting an armored target vehicle from incoming laser guided missiles in accordance with a third embodiment of the present invention. The figure illustrates a laser designated missile 32, which includes a sensor device which is sensitive to laser radiation scattered by the target 30. The laser radiation 34 is pointed at the target 30 from a distant laser designator 36 on the vehicle launching the guided missile 32. The illuminating laser radiation is formed into a narrow beam 34 so that only the target vehicle 30 is illuminated, and is in the form of a precisely timed pulse train. The laser seeking sensor or seeker provided on the missile 32 only reacts to the laser wavelength in use and to laser pulse trains with the correct timing characteristics.
The target 30 is illuminated by the laser designator 36 and in normal circumstances the seeker on the missile 32 is directed towards the scattered laser radiation 38 reflected by the target 30.
Existing laser repeater decoys illuminate a decoy point near the target 30 with a pulse train from a laser which is triggered by receipt of incoming laser pulses. However, in this embodiment of the present invention, the decoy is provided by an inflatable structure 40 mounted on the target vehicle 30. The structure is inflated and deployed upwards above the vehicle 30. The material forming the outer surface of the structure 40 is selected to provide a suitable visual camouflage and has very high diffuse scattering characteristics at the laser designator wavelength (1.06 microns). As in conventional laser decoy systems, a laser repeater 42 is triggered by the incoming laser pulse train 34. However, in this embodiment of the present invention, the pulse train 44 issuing from the laser repeater 42 is directed into the inflated structure 40, which scatters the laser energy, providing a strongly illuminated decoy source directly above the target vehicle 30. As the decoy is located directly above the target vehicle 30, the decoy geometry is intrinsically optimum for minimum time of flight difference, minimum angle selectivity and maximum apparent brightness of the decoy relative to the true designator pulse train.
When the laser designated missile 32 detects the scattered radiation 46 emitted by the decoy 40 the missile 32 will change its flight path to avoid the target vehicle 30 and will tend to fly through the inflated structure 40, which will shred and collapse under the impact.
As the decoy structure 40 is positioned above the target vehicle the "miss" distance may be closely controlled. The illuminated structure 40 is visible to missiles approaching from all directions, and directing the laser energy 44 into the structure ensures that the scattered energy 46 is emitted in all directions. However, in other embodiments the structure may be illuminated externally, allowing a laser 42 fitted to the vehicle for other purposes to be used to illuminate the decoy 40, or the laser energy may be conducted through an array of optical fibers 43 between the laser 42 and the structure 40, which fibers conduct the laser energy 44 to the desired position within or on the surface of the structure 40.
Reference is now made to FIG. 4 of the drawings, which is a schematic illustration of an arrangement for protecting an armored vehicle from an incoming laser guided missile in accordance with a fourth embodiment of the present invention. Like the third embodiment described above, this embodiment of the invention creates a laser emitting decoy, but this is achieved without provision of a laser repeater.
The target vehicle 50 is provided with first and second inflatable structures 54, 56, the first structure 54 being in the form of a sloping skirt which is inflated and deployed around the vehicle 50 and is formed of a material having high specular reflectivity and low diffuse reflectivity. The second inflatable structure 56 is arranged to be deployed above the target vehicle 50 and has a surface provided a high diffuse scattering co-efficient.
In use, the structures 54, 56 are inflated on detection of an incoming designator pulse train 58 by an appropriate sensor 60. The incoming laser energy is deflected upwardly by the first structure 54, greatly reducing the radiation scattered in the direction of an incoming missile seeker 52. The second structure 56 collects the reflected radiation and scatters the radiation so that it can be detected by the missile seeker. The seeker then aims at the higher second structure 56 which is now the strongest source of scattered laser light.
From the above-described embodiments it will be apparent to those of skill in the art that these decoy arrangements provide a simple yet effective means of protecting armored vehicles against laser designated missiles.
It will also be apparent to those of skill in the art that the above-described embodiments are merely exemplary of the present invention, and that various modifications and improvements may be made thereto, without departing from the scope of the invention.
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An arrangement for protecting an armored vehicle from incoming projectiles comprising an inflatable structure (12, 14; 22, 23; 40; 56) for mounting on a vehicle (10; 20; 30; 50). The structure is inflated on detection of an incoming projectile such that the inflated structure extends from the vehicle. The inflated structure may alter the signature of the vehicle as seen by incoming missiles, or may provide a decoy.
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CROSS-REFERENCE TO PRIOR APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application No. 60/204,874 filed May 16, 2000.
BACKGROUND OF THE INVENTION
[0002] This invention relates to film prepared from aqueous polyurethane dispersions. This invention particularly relates to aqueous polyurethane dispersions useful for preparing gloves.
[0003] While ostensibly reactive with water, it has long been known that polyisocyanate polymers can be used to prepare aqueous polyurethane dispersions. Polyurethane dispersions are generally prepared by chain extending the reaction product of an organic diisocyanate or polyisocyanate and an organic compound having two or more active hydrogen atoms such as polyalkylene ether glycols, poly(alkylene ether-alkylene thioether) glycols, alkyd resins, polyesters and polyester amides, often using an organic solvent. The diisocyanate is used in stoichiometric excess so that the reaction product, also referred to as a polyurethane/urea/thiourea prepolymer, is isocyanate terminated. Examples of polyurethane prepolymer preparations are described in U.S. Pat. Nos. 3,178,310; 3,919,173; 4,442,259; 4,444,976; and 4,742,095; among others.
[0004] Polyurethane dispersions are reported as being useful for preparing such diverse materials as: coatings and bonds in U.S. Pat. No. 4,292,226; flexible solvent barriers in U.S. Pat. No. 4,431,763; adhesives in U.S. Pat. No. 4,433,095; and films in U.S. Pat. No. 4,501,852. Films, or rather the process of dipping to make a film, can be a part of the processes for making many articles. Examples of film applications include exam gloves, organ bags, condoms, ostomy bags, and the like. While it is known that such applications can be made with polyurethane dispersions, conventional polyurethane dispersions have sometimes been found to have insufficient physical or handling properties to make them a preferred material for such applications. Also, the use of a solvent can have adverse effects for some applications.
[0005] Polyurethanes are the reaction product of a polyalcohol and a polyisocyanate. Typically, the polyisocyanates used to prepare polyurethane dispersions have been aliphatic isocyanates such are disclosed in U.S. Pat. No. 5,494,960. Aromatic polyisocyanates such as toluene diisocyanate (TDI) and methylene diphenyldiisocyanate (MDI) as well as polymethylene polyphenylisocyanate are also known to be useful.
[0006] Conventional processes of preparing films from dispersions, including polyurethane dispersions, generally include a step of coagulating the latex onto a substrate. It is therefore necessary that latexes used to make films have the property that they can be coagulated onto a substrate. At the same time, it is considered desirable in the art of making latex dispersions that the dispersions be stable, that is that they do not settle or spontaneously coagulate during shipping on storage. Accordingly, it would be desirable in the art of preparing aqueous dispersions useful for preparing films that the dispersions be capable of being coagulated onto a substrate using conventional coagulants and coagulation technology.
[0007] Films prepared from natural rubber latex are considered to have properties which are desirable from the perspective of comfort and utility. Unfortunately, natural rubber latex also includes proteins and other materials which can be irritating to skin.
[0008] It would be desirable in the art of preparing films to prepare a water-based film which has physical properties similar to natural rubber latex films but which doesn't include the dermal irritants which occur in natural rubber latex.
SUMMARY OF THE INVENTION
[0009] In one aspect, the present invention is a polyurethane film comprising a film prepared from an aqueous polyurethane dispersion, the dispersion being prepared from a nonionic polyurethane prepolymer and water, wherein the nonionic polyurethane prepolymer is prepared from a polyisocyanate and a low monol polyether polyol.
[0010] In another aspect, the present invention is a process for preparing an aqueous polyurethane dispersion comprising preparing a nonionic polyurethane prepolymer from a polyisocyanate and a low monol polyol; and admixing the nonionic polyurethane prepolymer with water.
[0011] In another aspect, the present inventions is a polyurethane dispersion prepared by preparing a nonionic polyurethane prepolymer from a polyisocyanate and a low monol polyol; and admixing the nonionic polyurethane prepolymer with water.
[0012] By utilizing a high molecular weight, low unsaturated polyol, the present invention has the advantage of being an economical, water-based polyurethane dispersion which has the desirable properties of natural latex rubber but does not include the dermal irritants which occur in natural rubber latex. The present invention can be used to prepare, for example, dipped rubber goods, such as gloves, condoms, catheters, and angioplasty balloons.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] The polyurethane prepolymer dispersions of the present invention are prepared by dispersing a nonionic polyurethane prepolymer in water using one or more external surfactants. The resulting polyurethane dispersion is useful for preparing films. For purposes of the present invention, the phrase “useful for preparing films” means that while the dispersions are sufficiently stable to be stored, they are not so stable that they cannot be electrodeposited or coagulated onto a substrate to make a film or other latex derived product.
[0014] The dispersions of the present invention can be prepared in any way which results in a dispersion which can be used to prepare a film having acceptable physical properties for the anticipated use of the film. The dispersions can be prepared by a batch process or by a continuous process. If prepared by a batch process, preferably the dispersion is prepared by an inverse phase process wherein a small amount of water, including a small amount of anionic surfactant, is first added to a continuous prepolymer phase and mixed and then more water is added with mixing until the phase inverts.
[0015] When dispersions of the process of the present invention are prepared by means of a continuous process, preferably they are prepared by means of a high internal phase ratio (HIPR) process. Such processes are known and are disclosed in, for Example, U.S. Pat. No. 5,539,021 to Pate et al., and U.S. Pat. No. 5,959,027 to Jakubowski et al. Other continuous dispersion processes can be used with the process of the present invention with the proviso that they result in a stable dispersion or at least a dispersion which is sufficiently dispersed to be further processed in the second step and result in a stable dispersion. For purposes of the present invention, a dispersion is stable if it does not settle, or separate out too quickly to be useful for its intended purpose.
[0016] When preparing the polyurethane dispersions of the present invention using more than one surfactant, the two surfactants can be added in two separate steps. In the first step, the first surfactant can be used to aid in dispersing the prepolymer. In the second step of the process of the present invention, the dispersion from the first step is admixed with a different external surfactant and admixed. The admixture of the second step may be prepared by any method which results in a stable polyurethane dispersion. The product of the second step of the process of the present invention, irrespective of admixing methods used, should have a particle size sufficient to make the dispersion stable. The dispersions of the present invention will have a particle size of from 0.9 to about 0.05, preferably from about 0.5 to about 0.07 and even more preferably, from about 0.4 to 0.10 microns. Most preferably, the particle size of the dispersions of the present invention is about 0.15 microns.
[0017] The polyurethane dispersions of the present invention are prepared from a nonionic polyurethane prepolymer. The nonionic prepolymers useful with the present invention are prepared with an aliphatic or aromatic diisocyanate. Preferably, the diisocyanate is an aromatic diisocyanate selected from the group consisting of MDI, TDI and mixtures thereof. TDI can be generally used with any commonly available isomer distribution. The most commonly available TDI has an isomer distribution of 80 percent of the 2,4 isomer and 20 percent of the 2,6 isomer. For the purposes of the present invention, TDI with other isomer distributions can also be used, but often at significantly higher cost.
[0018] When MDI is used with the formulations of the present invention, it preferably has a P,P′ isomer content of from about 99 percent to about 90 percent. Even more preferably, when MDI is used with the formulations of the present invention, it preferably has a P,P′ isomer content of from about 98 to about 92 percent. Most preferably, when MDI is used with the formulations of the present invention, it preferably has a P,P′ isomer content of about 94 percent. While MDI with such isomer distributions can be prepared by distillation during the MDI process, it can also be prepared by admixing commonly available products such as ISONATE 125M* and ISONATE 500P*. (*ISONATE 125M and ISONATE 500P are trade designations of The Dow Chemical Company.)
[0019] When mixtures of TDI and MDI are used to prepare the prepolymers useful with the present invention, they are admixed in a ratio of MDI to TDI of from about 99 percent MDI to about 80 percent MDI. More preferably, when mixtures of TDI and MDI are used to prepare prepolymers useful with the present invention, they are admixed in a ratio of MDI to TDI of from about 98 percent MDI to about 90 percent MDI. Most preferably, when mixtures of TDI and MDI are used to prepare the prepolymers useful with the present invention, they are admixed in a ratio of MDI to TDI of about 96 percent MDI. Preferably, the prepolymers useful with the present invention are prepared with MDI or mixtures of MDI and TDI. Even more preferably, the prepolymers useful with the present invention are prepared with MDI as the only aromatic diisocyanate.
[0020] In one embodiment of the present invention, the prepolymers useful with the present invention are prepared from a formulation that includes an active hydrogen containing material. In a preferred embodiment of the present invention, the active hydrogen containing material is a mixture of diols. One component of the preferred diol mixture is a high molecular weight polyether or polyester diol, for example a high molecular weight polyoxypropylene diol, optionally having an ethylene oxide capping of from 0 to 25 weight percent. The other component of the diol mixture is a low molecular weight diol.
[0021] Generally, the polyether diols of the formulations of the present invention can be prepared by any method known to those of ordinary skill in the art of preparing polyether polyols to be useful for preparing such diols.
[0022] The high molecular weight polyether diol component of the diol mixture of the prepolymer formulations of the present invention is a polyoxypropylene diol having an ethylene oxide capping of from 0 to 25 weight percent. Preferably, the molecular weight of this component is from about 1000 to about 10,000, more preferably from about 1500 to about 8000 and most preferably from about 2000 to about 6000. As stated, the polyether diol is optionally capped with from 0 to 25 percent ethylene oxide. In the alternative, a combination of polyethers having an average ethylene oxide capping of from 0 to 25 percent can also be used. Preferably, the high molecular weight diol is capped with from about 5 to about 25 percent ethylene oxide, and more preferably, from about 10 to about 15 percent ethylene oxide.
[0023] In the practice of the present invention, the high molecular weight polyether diol component of the diol mixture of the prepolymer formulations of the present invention is a low or ultra-low monol containing polyol. In the practice of preparing polyols using propylene oxide, occasionally rather than anionic polymerization of propylene oxide, an undesirable side reaction occurs resulting in a monol terminated with a double bond. These reactions are very common in alkali metal hydroxide catalyzed polyol processes. As the average molecular weight of a polyoxypropylene polyol increases during alkali metal hydroxide catalyzed synthesis, the concentration of monol increases until it reaches ranges of, for example, from 20 to 40 mole percent of monol for a 4000 molecular weight polyoxypropylene polyol. Generally, the level of unsaturation increases as the molecular weight of the polyol increases.
[0024] Low monol polyols are those with measured unsaturations, measured according to ASTM Designation D-4671-87, of less than about 0.025 meq/g, preferably less than about 0.020 meq/g, more preferably less than about 0.015 meq/g, even more preferably less than about 0.010 meq/g, and most preferably less than about 0.005 meq/g. The range of 0.001 to 0.005 meq/g is sometimes also referred to as ultra-low monol polyols. Such polyoxypropylene polyols may be prepared by any way known to be useful to one skilled in the art of preparing polyols. Because the low monol polyols have a relatively high molecular weight and a relatively low unsaturation, such low monol polyols are sometimes referred to as high molecular weight, low unsaturation polyols.
[0025] Polyols useful with the process of the present invention can be prepared using an alkali metal hydroxide catalyst followed by post treatment to hydrolyze the unsaturation. Another method of preparing such polyols is by use of the so called double metal cyanide catalysts. Hybrid processes can also be used. The actual method of catalysis is not important; the critical feature is the low unsaturation of less than 0.025 meq/g. The equivalent and molecular weights expressed herein are in Da (Daltons) and are number average equivalent and molecular weights. The low monol polyols should comprise a major portion, i.e. greater than 50 weight percent, preferably greater than 80 weight percent, of the polyol blend used to prepare the isocyanate-terminated prepolymer, and substantially all of the total polyether polyol portion of the polyol component should be a low unsaturation polyol such that the total polyol component unsaturation is less than 0.025 meq/g.
[0026] The low molecular weight diol component of some of the prepolymer formulations of the present invention can also be a product of alkoxylating a difunctional initiator. Preferably, this component is also a polyoxypropylene diol, but it can also be a mixed ethylene oxide propylene oxide polyol, as long as at least 75 weight percent of the alkoxides used, if present, is propylene oxide. Diols such as propylene glycol, diethylene glycol, dipropylene glycol, 1,4-butane diol, and the like, can also be used with the formulations of the present invention. The low molecular weight diol component of the prepolymer formulations, if present, has a molecular weight of from about 60 to about 750, preferably from about 62 to about 600, and most preferably, from about 125 to about 500. Typically, low molecular weight polyols are low monol polyols, but this low molecular weight polyol component can be a low monol polyol, a convention polyol or mixtures thereof.
[0027] The prepolymers useful with the present invention can be prepared in any way known to those of ordinary skill in the art of preparing polyurethane prepolymers. Preferably the diisocyanate and polyether diol mixture are brought together and heated under reaction conditions sufficient to prepare a polyurethane prepolymer. The stoichiometry of the prepolymer formulations of the present invention is such that the diisocyanate is present in excess. Preferably, the prepolymers useful with the present invention have an isocyanate content (also known as %NCO) of from about 1 to about 9 weight percent, more preferably from about 2 to about 8 weight percent, and most preferably from about 3 to about 7 weight percent.
[0028] The prepolymers useful with the present invention are optionally extended, sometimes using a difunctional amine chain extender when the active hydrogen containing material of the prepolymer formulation is a mixture of a low molecular weight diol and a high molecular weight polyether diol. The difunctional amine chain extender may not be optional, but rather be required when the active hydrogen containing material of the prepolymer formulation is a high molecular weight polyether diol and does not include a low molecular weight diol. Preferably, the difunctional amine chain extender, if present, is present in the water used to make the dispersion. When used, the amine chain extender can be any isocyanate reactive diamine or amine having another isocyanate reactive group and a molecular weight of from about 60 to about 450, but is preferably selected from the group consisting of: an aminated polyether diol; piperazine, aminoethylethanolamine, ethanolamine, ethylenediamine and mixtures thereof. The prepolymers are preferably chain extended to the point where no covalent cross-linking occurs, such that the resulting prepolymer has an average practical functionality of less than about 2.1. Preferably, the amine chain extender is dissolved in the water used to make the dispersion such that amine chain extension is carried out after the prepolymer has been initially emulsified in the water.
[0029] The prepolymers useful with the present invention are nonionic. That is, there are no ionic groups incorporated in or attached to the backbones of the prepolymers used to prepare the films of the present invention. The anionic surfactant used to prepare the dispersions of the present invention is a external stabilizer and is not incorporated into the polymer backbones of the films of the present invention.
[0030] The prepolymers useful with the present invention are dispersed in water which contains a surfactant. Preferably the surfactant is an anionic surfactant. In the practice of preparing the dispersions of the present invention, the surfactant is preferably introduced into water prior to a prepolymer being dispersed therein, but it is not outside the scope of the present invention that the surfactant and prepolymer could be introduced into the water at the same time. Any anionic surfactant can be used with the present invention, but preferably the anionic surfactant is selected from the group consisting of sulfonates, phosphates, and carboxylates. More preferably the anionic surfactant is sodium dodecyl benzene sulfonate, sodium dodecyl sulfonate, sodium dodecyl diphenyl oxide disulfonate, sodium n-decyl diphenyl oxide disulfonate, isopropylamine dodecylbenzenesulfonate, or sodium hexyl diphenyl oxide disulfonate.
[0031] In the practice of the process of the present invention, in an optional second step, a polyurethane dispersion prepared with a first external surfactant is admixed with a second and different external surfactant. Most preferably, the external surfactant used with the process of the present invention as the second step surfactant is triethanolamine lauryl sulfate. Other external surfactants can also be used in the second step of the process of the present invention and can either be the same surfactant as that used in the first step, or a different surfactant.
[0032] The dispersions of the present invention can have a solids level of from about 30 weight percent to about 60 weight percent. Films will not necessarily be prepared from dispersions having this level of solids. While the dispersions themselves will be stored and shipped at as high a solids content as possible to minimize storage volume and shipping costs, the dispersions can desirably be diluted prior to final use. The thickness of the film to be prepared and the method of coagulating the polymer onto a substrate will usually dictate what solids level is needed in the dispersion. When preparing films, the dispersions of the present invention can be at a weight percent solids of from 5 to about 60 percent, preferably from about 10 to about 40 percent, and, most preferably, from about 15 to about 25 weight percent when preparing examination gloves. For other applications, the film thickness and corresponding solids content of the dispersion used can vary.
[0033] Advantageously, films prepared using dispersion of the present invention can be prepared such that they are self-releasing. In the art of preparing exam gloves, this ability is also known as “powder free” in reference to the fact that such gloves are occasionally prepared and sold with a layer of talcum powder, corn starch, or the like, to keep the polymer from adhering to itself, thereby making it easier to put on the gloves. The films of the present invention can be made self releasing by any method known to those of ordinary skill in preparing gloves to useful for preparing powder free gloves.
[0034] Any additive which is known to those of ordinary skill in the art of preparing films from dispersion to be useful can be used with the process of the present invention so long as their presence does not degrade the properties of the dispersions or films prepared therewith so much that the films are no longer fit for their intended purposes. The additives can also be incorporated into the formulations or films in any way known to be useful including, but not limited to inclusion in the prepolymer formulation and inclusion in the water used to make the dispersion. For example titanium dioxide is useful for coloring films of the present invention. Other useful additives include calcium carbonate, silicon oxide, defoamers, biocides, carbon particles, and the like.
[0035] The following examples are for illustrative purposes only and are not intended to limit the scope of the claimed invention. Percentages are in weight percents unless otherwise stated.
EXAMPLES
[0036] The following materials are used in the examples below:
[0037] Polyether Polyol I is a low monol (unsaturation=0.001 meq/g) 4000 molecular weight polyoxypropylene diol having 12 percent ethylene oxide end capping.
[0038] Polyether Polyol II is a low monol (unsaturation=0.005 meq/g) 3750 molecular weight polyoxypropylene diol having 12 percent ethylene oxide end capping.
[0039] Low Molecular Weight Diol is a 134 molecular weight all polyoxypropylene diol (dipropyleneglycol).
[0040] Polyisocyanate A is MDI having a 4,4′ isomer content of 98 percent and an isocyanate equivalent weight of 125 (ISONATE*125M from The Dow Chemical Company).
[0041] Chain extender is a 104 molecular weight diamine (aminoethylethanolamine).
[0042] Surfactant is a 22 wt. % solution of sodium dodecylbenzene sulfonate in water.
Example 1
[0043] A polyurethane prepolymer is prepared by admixing 72.0 parts of Polyether Polyol 1, and 4.0 parts Low Molecular Weight Diol and then heating the admixture to 50° C. This material is then admixed with 24.0 parts of Polyisocyanate I which has also been warmed to 50° C. The admixture is then heated at 70° C. for 6 hours and then tested to determine NCO content. The NCO content is 4.0 percent.
[0044] A polyurethane dispersion is prepared by admixing 200 g of the prepolymer admixed with 14 g water and 34 g surfactant using a high shear mixer running at about 2500 rpm. 258 g additional water is slowly added until a phase inversion is observed.
[0045] A film is then prepared by a coagulation process by heating a steel plate in an oven until it reached a temperature of from 100 to 120° F. (38-49° C.). The plate is then dipped into a 20 percent solution of calcium nitrate in 1:1 by weight of water and methanol which also included about 1 wt % of a ethoxylated octylphenol surfactant. The plate is then placed into an oven at 230° F. (1 10° C.) for approximately 15 minutes to form a very thin film of calcium nitate on the plate. The plate is allowed to cool to 105° F. (40° C.) and then dipped into the polyurethane dispersion diluted to 23% solids with deionized water and removed (total dwell time is approximately 20 sec). The plate is held for 5 minutes at room temperature to allow the film to generate enough gel strength, followed by leaching in a water bath at 115° F. (46° C.) for 10 minutes. Both sides of the plate is then sprayed with water at 115° F. (40° C.) for two additional minutes. The plate is then heated to 230° F. (1 10° C.) for 30 minutes and then cooled to ambient temperature. A polyurethane film is peeled from the substrate and tested using ASTM Designation D 412-98a (Die C; overall length=4.5″, width of narrow section=0.25″, and gauge length=1.31″) Testing results are presented in the table. It is tactilely soft and yet has good physical properties.
Example 2
[0046] A Prepolymer is prepared the same as in Example 1. However, during the dispersion process the diamine is used during final dilution step to replace some of the water extension. The amount of diamine used is calculated to react with 25% of available isocyanate in prepolymer.
Examples 3
[0047] A polyurethane prepolymer is prepared by admixing 71.5 parts of Polyether Polyol I, and 4.0 parts Low Molecular Weight Diol and then heating the admixture to 50° C. This material is then admixed with 24.5 parts of Polyisocyanate I which has also been warmed to 50° C. The admixture is then heated at 70° C. for 6 hours and then tested to determine NCO content. The NCO content is 4.0 percent.
[0048] The dispersion and films were made using same procedure as in Example 1.
Example 4
[0049] A prepolymer is prepared the same as in Example 3. However, during the dispersion process the diamine is used during final dilution step to replace some of the water extension. The amount of diamine used is calculated to react with 25% of available isocyanate in prepolymer.
TABLE I EXAMPLE 1 2 3 4 POLYETHER 72 72 POLYOL I (parts by wt) POLYETHER 71.5 71.5 POLYOL II (parts by wt) LOW MWT DIOL 4 4 4 4 (parts by wt) POLY- 24 24 24.5 24.5 ISOCYANATE A (parts by wt) % NCO 4.0 4.0 4.0 4.0 Chain Extender .25 .25 stoichiometry stoichiometry TENSILE 1860 2590 2039 3304 STRENGTH (PSI) ELONGATION AT 1054 929 892 836 BREAK (%) STRESS AT 100% 248 200 321 250 ELONGATION (PSI)
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Aqueous polyurethane dispersions and films prepared therefrom are prepared from a nonionic polyurethane prepolymer and water. The nonionic polyurethane prepolymer is prepared from a diisocyanate and a low monol polyether polyol. Such dispersions and films have applicability in gloves, condoms, angioplasy balloons and the like.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of Korean Patent Application No. 10-2004-0114658 filed on Dec. 29, 2004, which is hereby incorporated by reference for all purposes as if fully set forth herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an image sensor, and more particularly, to a CMOS image sensor and a method for fabricating the same, which improves the sensor's image characteristics.
2. Discussion of the Related Art
Image sensors are semiconductor devices for converting an optical image into an electrical signal and include charge-coupled devices and complementary metal-oxide-semiconductor (CMOS) image sensors. A general charge-coupled device includes an array of photodiodes converting light signals into electrical signals. Disadvantages of a charge-coupled device include a complicated driving method, high power consumption, and a complicated fabrication process requiring a multi-phased photo process. In a charge-coupled device, integration of complementary circuitry such as a control circuit, a signal processor, and an analog-to-digital converter into a single-chip device is difficult. Thus, development of compact-sized or thin products using such image sensors is hindered. Examples of compact-sized or thin products include digital still cameras and digital video cameras.
CMOS image sensors, on the other hand, adopt CMOS technology using a control circuit and a signal processing circuit as a peripheral circuit. CMOS image sensors also adopt switching technology which allows outputs to be sequentially detected using MOS transistors corresponding to a number of arrayed pixels. This allows an image to be detected. Accordingly, a CMOS image sensor uses CMOS fabrication technology, i.e., a simple fabrication method using fewer photolithography steps, thereby enabling an advantageous device exhibiting low power consumption.
In the aforementioned CMOS image sensor of the related art, the photodiode is the active device for forming an optical image based on incident light signals. The optical image is formed by generating electrical signals according to the intensity and wavelength or color of incident light. In such a CMOS image sensor, each photodiode senses incident light and the corresponding CMOS logic circuit converts the sensed light into an electrical signal according to input wavelength. The photosensitivity of the photodiode increases as more light is able to reach the photodiode. In this instance, enhanced photosensitivity results from an increase in the levels of sensed light and corresponds to the light-receiving capability of the active device. One way of enhancing the photosensitivity of a CMOS image sensor is to improve its “fill factor,” i.e., the degree of surface area covered by the photodiodes versus the entire surface area of the image sensor. The fill factor is improved by increasing the area responsive to incident light, i.e., the photo-sensing portion. However, there is a limit to increasing the photo-sensing portion due to the required presence of the logic circuit portion.
Therefore, a device of a material exhibiting excellent light transmittance, such as a convex microlens having a predetermined curvature for refracting incident light, may be provided to redirect any light that may be incident on the image sensor outside the immediate area of the photodiodes. The device may also be provided to concentrate or focus the incident light on one or more of the photodiodes themselves. That is, the incident light, striking the surface of the convex structure of the microlens while in parallel to the optical axis of the microlens, is refracted by the microlens according to the curvature of the convex structure. The incident light is thereby focused at a predetermined point along the optical axis. Accordingly, in a color image sensor, such a microlens may be provided over a color filter layer including red (R), blue (B), and green (G) filter elements for passing the light of each color or wavelength to be disposed over a photodiode area.
Meanwhile, CMOS image sensors are classified according to a number of transistors. For example, a 3T-type CMOS image sensor consists of one photodiode and three transistors and a 4T-type CMOS image sensor consists of one photodiode and four transistors. An equivalent circuit and layout of a unit pixel of a 3T-type CMOS image sensor of the related art are shown in FIG. 1 and FIG. 2 , respectively.
Referring to FIG. 1 , a CMOS image sensor of the related art comprises one photodiode PD and three NMOS transistors including a reset transistor Rx, a drive transistor Dx, and a select transistor Sx. The cathode of the photodiode PD is commonly connected to the drain of the reset transistor Rx and the gate of the drive transistor Dx, whose drain is connected to the source of the select transistor Sx, whose drain is in turn connected to a read circuit. With the anode of the photodiode PD grounded, a reference voltage V R is applied via a power line to the source of each of the reset and drive transistors Rx and Dx. A reset signal RST is applied via a reset line to the gate of the reset transistor Rx and a select signal SLCT is applied via a column select line to the gate of the select transistor Sx.
Referring to FIG. 2 , an active area 100 is defined for each unit pixel of the CMOS image sensor of FIG. 1 . The active area 100 includes a photodiode area 20 comprising the bulk of the active area, which is overlapped by gate electrode areas 120 , 130 , and 140 of the three NMOS transistors, respectively. The source/drain region of each transistor is formed by an ion-implantation process with respect to the active area 100 . Power (Vdd) is applied to the source/drain regions of the reset transistor Rx and drive transistor Dx. The source/drain region of the select transistor Sx is connected to the read circuit. Each of the gate electrodes 120 , 130 , and 140 is connected to external circuitry (not shown) via a corresponding signal line having a pad provided at one end.
As shown in FIG. 3 , a CMOS image sensor of the related art includes a plurality of photodiodes 11 formed in a surface of a semiconductor substrate 10 , an insulating interlayer 12 formed on the entire surface of the semiconductor substrate 10 including the photodiodes 11 , a first planarization layer (not shown) formed on the insulating interlayer 12 , a color filter layer 14 formed on the first planarization layer, a second planarization layer 15 formed on the entire surface of the semiconductor substrate 10 including the color filter layer 14 , and a plurality of microlenses 16 provided on the second planarization layer 15 corresponding to the respective photodiodes 11 , each microlens being formed as convex structure and having a predetermined curvature. The microlenses 16 focus incident light onto the corresponding photodiodes 11 through the color filter layer 14 . The color filter layer 14 is comprised of red (R), green (G), and blue (B) color filter patterns for respectively filtering light according to wavelength. Each of the photodiodes 11 is disposed below one of the color filter patterns and generates an electrical charge according to the amount of incident light that reaches the photodiode.
The curvature and height of the microlens, which is a critical component of an image sensor, are determined in due consideration of the desired focus of incident light. Generally, the microlens is made of polymer-based resin enabling a completed microlens to be formed using only a photolithography patterning process of exposure and development followed by a reflowing process. The pattern profile or shape of the microlens tends to vary according to exposure conditions, for example, the conditions of a thin film on the semiconductor substrate, which are rather unstable. This results in degraded focusing characteristics. The microlens is nevertheless formed to have the optimal size, thickness, and curvature radius, which are determined with due regard to such parameters as shape, size, and positioning of a unit pixel, photodiode thickness, and physical characteristics (e.g., dimensions) of a light-shielding layer.
Meanwhile, the respective color filter patterns have different heights since each is formed by its own individual photolithography processing. Therefore, the planarization layer 15 provides a level surface, above the upper surfaces of the color filter patterns, for receiving the microlens array. Accordingly, as shown in FIG. 3 , the traveling distance a of light, which passes through the microlens 16 to be incident on the photodiode 11 , is inherently increased due to the thickness of the planarization layer 15 . Since the light-receiving efficiency of the CMOS image sensor of the related art depends on the amount of light reaching the photodiode, light sensitivity is lowered due to the greater traveling distance, thereby deteriorating the capacity of the CMOS image sensor.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a CMOS image sensor and a method for fabricating the same that substantially obviates one or more problems due to limitations and disadvantages of the related art.
An advantage of the present invention is to provide a CMOS image sensor and a method for fabricating the same that improves image characteristics by eliminating the thickness of a planarization layer.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, there is provided a CMOS image sensor comprising a semiconductor substrate; a plurality of active devices, provided in a predetermined surface of the semiconductor substrate, for generating electrical charges according to an amount of incident light; an insulating interlayer formed on an entire surface of the semiconductor substrate including the plurality of active devices; a color filter layer formed on the insulating interlayer, the color filter layer comprised of red, green, and blue color filter patterns for respectively filtering light according to wavelength, the color filter patterns arranged to correspond to the plurality of active devices; and a plurality of microlenses formed on the color filter layer, wherein the color filter layer is planarized so that each color filter pattern of the color filter layer is imparted with an equal height for receiving the plurality of microlenses.
In another aspect of the present invention, there is provided a method for fabricating a CMOS image sensor. The method comprises forming a plurality of photodiodes in a predetermined surface of a semiconductor substrate; forming an insulating interlayer on an entire surface of the semiconductor substrate including the plurality of photodiodes; forming a color filter layer including red, green, and blue color filter patterns on the insulating interlayer; planarizing the color filter layer so that each color filter pattern of the color filter layer is imparted with an equal height; and forming a plurality of microlenses on the planarized color filter layer.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. In the drawings:
FIG. 1 is an equivalent circuit view of a 3T-type CMOS image sensor of the related art;
FIG. 2 is a layout of a unit pixel in a 3T-type CMOS image sensor of the related art;
FIG. 3 is a cross-sectional view of a CMOS image sensor of the related art;
FIGS. 4A-4C are cross-sectional views illustrating a method for fabricating a CMOS image sensor according to an embodiment of the present invention; and
FIGS. 5A-5D are cross-sectional views illustrating a method for fabricating a CMOS image sensor according to another embodiment of the present invention.
FIGS. 6A-6D are cross-sectional views illustrating a method for fabricating a CMOS image sensor according to another embodiment of the present invention
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, like reference designations will be used throughout the drawings to refer to the same or similar parts.
An embodiment of the present invention will be described with reference to FIG. 4A-5C . As shown in FIG. 4A , a plurality of photodiodes 41 , which may be in the form of a plurality of photo-gates, are formed at fixed intervals in a predetermined surface of a semiconductor substrate 40 . Then, an insulating interlayer 42 of an oxide such as undoped silicate glass is formed on an entire surface of the semiconductor substrate 40 including the plurality of photodiodes 41 . The insulating interlayer 42 may be formed as a multi-layered structure, including a light-shielding layer (not shown) for preventing light from reaching areas other than the photodiodes 41 , and another insulating interlayer (not shown) formed on the light-shielding layer.
Subsequently, respective resist layers of green (G), blue (B), and red (R) are coated on the insulating interlayer 42 , and then an exposure and development process is performed with respect to each layer of resist, thereby forming a color filter layer 43 including the green (G), blue (B), and red (R) color filter patterns. The color filter patterns are arranged to correspond to a plurality of active devices, such as photodiodes 41 , for filtering light according to wavelength. The respective color filter patterns have different heights since each is formed by its own individual photolithography processing.
Referring to FIG. 4B , a chemical-mechanical polishing process or an etching process is performed with respect to the entire surface of the color filter layer 43 including each of the color filter patterns, thereby forming a planarized color filter layer 43 . That is, the polishing process or the etching process serves to planarize the surface of the color filter layer 43 . As a result, each color filter pattern is imparted with an equal height for receiving an array of microlenses.
In FIG. 4C , a sacrificial layer (not shown) for microlens formation is coated on the planarized color filter layer 43 , and an exposure and development process is performed with respect to the sacrificial layer, thereby forming a microlens pattern corresponding to an array of microlenses. The sacrificial layer may be formed as a resist layer or an oxide layer of tetra-ethyl-ortho-silicate. A plurality of microlenses 44 is formed by reflowing the microlens pattern. The reflowing process may employ a hot plate or a furnace. The curvature of the microlenses 44 can be varied to control focusing according to an application of a heat shrinkage method. Subsequently, the microlenses 44 are irradiated with ultraviolet light, thereby curing each microlens to maintain its optimal curvature radius.
Another embodiment of the present invention will be described with reference to FIG. 5A-5D . As shown in FIG. 5A , a plurality of photodiodes 31 , which may be in the form of a plurality of photo-gates, are formed at fixed intervals in a predetermined surface of a semiconductor substrate 30 . Then, an insulating interlayer 32 of an oxide such as undoped silicate glass is formed on an entire surface of the semiconductor substrate 30 including the plurality of photodiodes 31 . The insulating interlayer 32 may be formed as a multi-layered structure, including a light-shielding layer (not shown) for preventing light from reaching areas other than the photodiodes 31 , and another insulating interlayer (not shown) formed on the light-shielding layer.
Subsequently, respective resist layers of green (G), blue (B), and red (R) are coated on the insulating interlayer 32 , and then an exposure and development process is performed with respect to each layer of resist, thereby forming a color filter layer 33 including the green (G), blue (B), and red (R) color filter patterns. The color filter patterns are arranged to correspond to the plurality of active devices, such as photodiodes 31 , for filtering light according to wavelength. The respective color filter patterns have different heights since each is formed by its own individual photolithography processing.
As shown in FIG. 5B , a planarization layer 34 is formed on the entire surface of the semiconductor substrate 30 , including the color filter patterns, to fill any crevices in the color filter layer 33 that may be present in the underlying surface, for example, between the color filter patterns. The planarization layer 34 should cover the highest surface among the respective color filter patterns and will serve as a sacrificial layer.
Referring to FIG. 5C , a chemical-mechanical polishing process or an etching process is performed with respect to the entire surface of the planarization layer 34 . The planarization layer 34 and the respective color filter patterns of the color filter layer 33 are simultaneously polished or simultaneously etched. The planarization layer 34 enables less removal of one or more of the color filter patterns of the color filter layer 33 . Thereby an excessive reduction in filter layer thickness, which may occur in striving for full planarization by polishing or etching the color filter layer directly, is avoided. That is, there may be remnants of the planarization layer 34 left after the polishing step or etching step, such that material of the planarization layer 34 is disposed between the color filter patterns of the color filter layer 33 . Thus, with minor portions (not shown) of the planarization layer 34 remaining as necessary, each color filter pattern is imparted with an equal height for receiving an array of microlenses.
In FIG. 5D , a sacrificial layer for microlens formation is coated on the planarized color filter layer 33 , and then an exposure and development process is performed with respect to the sacrificial layer, thereby forming a microlens pattern corresponding to an array of microlenses. The sacrificial layer may be formed as a resist layer or an oxide layer of tetra-ethyl-ortho-silicate. A plurality of microlenses 35 is formed by reflowing the microlens pattern. The reflowing process may employ a hot plate or a furnace. The curvature of the microlenses 35 can be varied to control focusing according to an application of a heat shrinkage method. Subsequently, the microlenses 35 are irradiated with ultraviolet light, thereby curing each microlens to maintain its optimal curvature radius.
Another embodiment of the present invention will be described with reference to FIG. 6A-6D . As shown in FIG. 6A , a plurality of photodiodes 31 , which may be in the form of a plurality of photo-gates, are formed at fixed intervals in a predetermined surface of a semiconductor substrate 30 . Then, an insulating interlayer 32 of an oxide such as undoped silicate glass is formed on an entire surface of the semiconductor substrate 30 including the plurality of photodiodes 31 . The insulating interlayer 32 may be formed as a multi-layered structure, including a light-shielding layer (not shown) for preventing light from reaching areas other than the photodiodes 31 , and another insulating interlayer (not shown) formed on the light-shielding layer.
Subsequently, respective resist layers of green (G), blue (B), and red (R) are coated on the insulating interlayer 32 , and then an exposure and development process is performed with respect to each layer of resist, thereby forming a color filter layer 33 including the green (G), blue (B), and red (R) color filter patterns. The color filter patterns are arranged to correspond to the plurality of active devices, such as photodiodes 31 , for filtering light according to wavelength. The respective color filter patterns have different heights since each is formed by its own individual photolithography processing.
As shown in FIG. 6B , a planarization layer 34 is formed on the entire surface of the semiconductor substrate 30 , including the color filter patterns, to fill any crevices in the color filter layer 33 that may be present in the underlying surface, for example, between the color filter patterns. The planarization layer 34 should cover the highest surface among the respective color filter patterns and will serve as a sacrificial layer.
Referring to FIG. 6C , a chemical-mechanical polishing process or an etching process is performed to partially remove the planarization layer 34 . The planarization layer 34 and one of the respective color filter patterns, such as the green color filter pattern, of the color filter layer 33 are simultaneously polished or simultaneously etched. The planarization layer 34 enables less removal of one or more of the color filter patterns of the color filter layer 33 . Thereby an excessive reduction in filter layer thickness, which may occur in striving for full planarization by polishing or etching the color filter layer directly, is avoided. That is, there may be remnants of the planarization layer 34 left after the polishing step or etching step, such that material of the planarization layer 34 is disposed between the color filter patterns of the color filter layer 33 . Thus, with minor portions (not shown) of the planarization layer 34 remaining as necessary, each color filter pattern is imparted with an equal height for receiving an array of microlenses.
In FIG. 6D , a sacrificial layer for microlens formation is coated on the planarized color filter layer 33 , and then an exposure and development process is performed with respect to the sacrificial layer, thereby forming a microlens pattern corresponding to an array of microlenses. The sacrificial layer may be formed as a resist layer or an oxide layer of tetra-ethyl-ortho-silicate. A plurality of microlenses 35 is formed by reflowing the microlens pattern. The reflowing process may employ a hot plate or a furnace. The curvature of the microlenses 35 can be varied to control focusing according to an application of a heat shrinkage method. Subsequently, the microlenses 35 are irradiated with ultraviolet light, thereby curing each microlens to maintain its optimal curvature radius.
By adopting the CMOS image sensor and method for fabricating the same according to the present invention, no planarization layer is needed between the color filter layer and the microlens since the color filter layer itself is imparted with a planarized upper surface. Accordingly, because the thickness of the planarization layer is eliminated, the traveling distance of light passing through the microlens to be incident on the photodiode can be decreased, thereby improving the image characteristics of the sensor.
It will be apparent to those skilled in the art that various modifications and variation can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
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A CMOS image sensor and method for fabricating the same improve image characteristics by eliminating the thickness of a planarization layer. The CMOS image sensor includes a semiconductor substrate; a plurality of active devices, provided in a predetermined surface of the semiconductor substrate, for generating electrical charges according to an amount of incident light; an insulating interlayer formed on an entire surface of the semiconductor substrate including the plurality of active devices; a color filter layer formed on the insulating interlayer, the color filter layer comprised of red, green, and blue color filter patterns for respectively filtering light according to wavelength, the color filter patterns arranged to correspond to the plurality of active devices; and a plurality of microlenses formed on the color filter layer, wherein the color filter layer is planarized so that each color filter pattern of the color filter layer is imparted with an equal height for receiving the plurality of microlenses.
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TECHNICAL FIELD
[0001] The following example embodiments relate to a method and apparatus for transmitting a payload sequence.
RELATED ART
[0002] In general, a modulation scheme of a digital wireless communication system may be classified into a noncoherent modulation scheme and a coherent modulation scheme. The noncoherent modulation scheme may be suitable for a noncoherent receiver having a low power consumption and a low complexity, and the coherent modulation scheme may be suitable for a coherent receiver having relatively small constraints on a power consumption and a complexity and also having an excellent performance.
SOLUTIONS
[0003] A transmitter according to an example embodiment includes a first signal converter configured to convert a ternary payload sequence including elements of −1, 0, or 1, to a first signal, wherein the first signal converter includes a ternary sequence mapper configured to generate the ternary payload sequence by mapping a pre-designed sequence to a binary data sequence; and a converter configured to convert the ternary payload sequence to the first signal.
[0004] The ternary sequence mapper may be configured to divide a binary data sequence including elements of 0 or 1 based on a predetermined length, and to map the pre-designed ternary sequence to the divided binary data sequence.
[0005] The first signal converter may include a pulse shaping filter figured to adjust a transmit power spectrum of the first signal.
[0006] The transmitter may further include a second signal converter configured to convert the first signal to the second signal by converting each section of the first signal based on the element.
[0007] The second signal converter may include a zero-value converter configured to convert a section corresponding to the element of 0 in the first signal; and an absolute one value converter configured to convert a section corresponding to the element of 1 and a section corresponding to the element of −1 in the first signal.
[0008] The zero-value converter may include a zero-value detector configured to detect the section corresponding to the element of 0 in the first signal.
[0009] The zero-value converter may include an ON-OFF controller configured to turn OFF an output of the section corresponding to the element of 0.
[0010] The absolute one value converter may include an absolute value detector configured to detect a section corresponding to an absolute one value in the first signal; and a sign detector configured to detect a sign of the element of the absolute one value, and to classify the section corresponding to the element of the absolute one value into the section corresponding to the element of 1 and the section corresponding to the element of −1.
[0011] The absolute one value converter may include a frequency shifter configured to shift a frequency of the section corresponding to the element of 1 to a first frequency, and to shift a frequency of the section corresponding to the element of −1 to a second frequency, in the first signal.
[0012] The absolute one value converter may include a phase shifter configured to shift a phase of the section corresponding to the element of 1 to a first phase, and to shift a phase of the section corresponding to the element of −1 to a second phase, in the first signal.
[0013] The absolute one value converter may include a frequency shifter configured to shift a frequency of the section corresponding to the element of 1 to a first frequency and to shift a frequency of the section corresponding to the element of −1 to a second frequency, in the first signal; and a phase shifter configured to shift a phase of the section corresponding to the element of 1 and to shift a phase of the section corresponding to the element of −1 to a second phase, in the first signal.
[0014] The second signal converter may include an amplifier configured to amplify an amplitude of die second signal.
[0015] The ternary sequence mapper may be configured to extract, from the following Table 1, a ternary sequence corresponding to the binary data sequence as the pre-designed ternary sequence, and in the following Table 1, C 0 denotes a sequence of [0 0 0 1 −1 0 1 1] and C m denotes a sequence acquired by cyclic shifting C 0 to right by in where m denotes an integer between 1 and 7.
[0000]
TABLE 1
Binary data sequence
Data symbol
Ternary sequence
3-tuple
m ∈
c m ∈
000
0
c 0
100
1
c 1
110
2
c 2
010
3
c 3
011
4
c 4
111
5
c 5
101
6
c 6
001
7
c 7
[0016] The ternary sequence mapper may be configured to extract, from the following Table 2, a ternary sequence corresponding to the binary data sequence as the pre-designed ternary sequence, and in the following Table 2, C 0 denotes a sequence of [−1 0 0 1 0 1 −1 0 −1 −1 1 −1 0 1 0 1 0 0 0 1 0 0 1 1 −1 0 0 0 0 0 1 1] and C m denotes a sequence acquired by cyclic shifting C 0 to right by m where m denotes an integer between 1 and 31.
[0000]
TABLE 2
Binary data sequence
Data symbol
Ternary sequence
5-tuple
m ∈
c m ∈
00000
0
c 0
10000
1
c 1
11000
2
c 2
01000
3
c 3
01100
4
c 4
11100
5
c 5
10100
6
c 6
00100
7
c 7
00110
8
c 8
10110
9
c 9
11110
10
c 10
01110
11
c 11
01010
12
c 12
11010
13
c 13
10010
14
c 14
00010
15
c 15
00011
16
c 16
10011
17
c 17
11011
18
c 18
01011
19
c 19
01111
20
c 20
11111
21
c 21
10111
22
c 22
00111
23
c 23
00101
24
c 24
10101
25
c 25
11101
26
c 26
01101
27
c 27
01001
28
c 28
11001
29
c 29
10001
30
c 30
00001
31
c 31
[0017] A transmitter according to an example embodiment includes a ternary sequence mapper configured to generate a ternary payload sequence including elements of −1 , 0, or 1 by mapping a pre-designed ternary sequence to a binary data sequence; and a converter configured to convert the ternary payload sequence to a signal, wherein the ternary sequence mapper is configured to extract, from the following Table 3, a ternary sequence corresponding to the binary data sequence as the pre-designed ternary sequence, and in the following Table, 3, C 0 denotes a sequence of [0 0 0 1 −1 0 1 1] and C, denotes a sequence acquired by cyclic shifting C 0 to right by in where m denotes an integer between 1 and 7.
[0000]
TABLE 3
Biliary data sequence
Data symbol
Ternary sequence
3-tuple
m ∈
c m ∈
000
0
c 0
100
1
c 1
110
2
c 2
010
3
c 3
011
4
c 4
111
5
c 5
101
6
c 6
001
7
c 7
[0018] A transmitter according to an example embodiment includes a ternary sequence mapper configured to generate a ternary payload sequence including elements of −1, 0, or 1 by mapping a pre-designed ternary sequence to a binary data sequence; and a converter configured to convert the ternary payload sequence to a signal, wherein the ternary sequence mapper is configured to extract, from the following Table 4, a ternary sequence corresponding to the binary data sequence as the pre-designed ternary sequence, and in the following Table 4, C 0 denotes a sequence of [−1 0010 1 −1 0 −1 −1 1 −1 0 1 0 1 0 0 0 1 0 0 1 1 −1 0 0 0 0 0 1 1] and C m denotes a sequence acquired by cyclic shifting C 0 to right by m where m denotes an integer between 1 and 31.
[0000]
TABLE 4
Binary data sequence
Data symbol
Ternary sequence
5-tuple
m ∈
c m ∈
00000
0
c 0
10000
1
c 1
11000
2
c 2
01000
3
c 3
01100
4
c 4
11100
5
c 5
10100
6
c 6
00100
7
c 7
00110
8
c 8
10110
9
c 9
11110
10
c 10
01110
11
c 11
01010
12
c 12
11010
13
c 13
10010
14
c 14
00010
15
c 15
00011
16
c 16
10011
17
c 17
11011
18
c 18
01011
19
c 19
01111
20
c 20
11111
21
c 21
10111
22
c 22
00111
23
c 23
00101
24
c 24
10101
25
c 25
11101
26
c 26
01101
27
c 27
01001
28
c 28
11001
29
c 29
10001
30
c 30
00001
31
c 31
[0019] A receiver according to an example embodiment includes an envelope detector configured to detect an amplitude value of an envelope of a received signal that is converted from a ternary payload sequence including elements of −1, 0, or 1; and a binary data sequence detector configured to detect a binary data sequence corresponding to the ternary payload sequence based on a correlation between the detected amplitude value of the envelope and desired binary sequences.
[0020] The receiver may further include a filter configured to filter the received signal using a first frequency. The envelope detector may be configured to detect an envelope of the filtered received signal.
[0021] The first frequency may be a frequency between a second frequency denoting a frequency and a third frequency, the second frequency denoting a frequency of a section of the received signal converted from the element of 1 in the ternary payload sequence and the third frequency denoting a frequency of a section of the received signal converted from the element of −1 in the ternary payload sequence.
[0022] The binary data sequence detector may be configured to detect a bit sequence corresponding to a binary sequence having a highest correlation with the detected amplitude value of the envelope among the binary sequences as the binary data sequence.
[0023] A receiver according to an example embodiment includes an entire envelope detector configured to detect an amplitude value of an envelope of a received signal converted from a ternary payload sequence including elements of −1, 0, or 1 and a binary data sequence detector configured to detect a binary data sequence corresponding to the ternary payload sequence based on a correlation between the detected amplitude value of the envelope and desired ternary sequences.
[0024] The entire envelope detector may include a first filter configured to filter the received signal using a first frequency; a second filter configured to filter the received signal using a second frequency; a first envelope detector configured to detect a first envelope that indicates an envelope of the received signal filtered using the first frequency; a second envelope detector configured to detect a second envelope that indicates an envelope of the received signal filtered using the second frequency; and a calculator configured to extract a third envelope based on a difference between the first envelope and the second envelope.
[0025] The binary data sequence detector may be configured to detect a bit sequence corresponding to a ternary sequence having a highest correlation with the third envelope among the ternary sequences as the binary data sequence.
[0026] A receiver according to an example embodiment includes a correlation detector configured to detect a correlation between a received signal converted from a ternary payload sequence including elements of −1, 0, or 1 and a reference signal; and a binary data sequence detector configured to detect a binary data sequence corresponding to the ternary payload sequence based on a correlation between a result value of the correlation and desired ternary sequences.
[0027] The binary data sequence detector may be configured to detect a bit sequence corresponding to a ternary sequence having a highest correlation with the result value of the correlation among the ternary sequences as the binary data sequence.
[0028] A receiver according to an example embodiment includes a signal receiver configured to receive a signal modulated from a ternary payload sequence generated by mapping a pre-designed ternary sequence to a binary data sequence and including elements of −1, 0, or 1; and a detector configured to detect the pre-designed ternary sequence and the binary data sequence by referring to the following Table 5. In the following Table 5, C 0 denotes a sequence of [0 0 0 1 −1 0 1 1] and C, denotes a sequence acquired by cyclic shifting C 0 to right by m where in denotes an integer between 1 and 7.
[0000]
TABLE 5
Binary data sequence
Data symbol
Ternary sequence
3-tuple
m ∈
c m ∈
000
0
c 0
100
1
c 1
110
2
c 2
010
3
c 3
011
4
c 4
111
5
c 5
101
6
c 6
001
7
c 7
[0029] A receiver according to an example embodiment includes a signal receiver configured to receive a signal modulated from a ternary payload sequence generated by mapping a pre-designed ternary sequence to a binary data sequence and including elements of −1, 0, or 1; and a detector configured to detect the pre-designed ternary sequence and the binary data sequence by referring to the following Table 6. In the following Table 6, C 0 denotes a sequence of [−1 0 0 1 0 1 −1 0 −1 −1 1 −1 0 1 0 1 0 0 0 1 0 0 1 1 −1 0 0 0 0 0 1 1] and C m denotes a sequence acquired by cyclic shifting C 0 to right by in where m denotes an integer between 1 and 31.
[0000]
TABLE 6
Binary data sequence
Data symbol
Ternary sequence
5-tuple
m ∈
c m ∈
00000
0
c 0
10000
1
c 1
11000
2
c 2
01000
3
c 3
01100
4
c 4
11100
5
c 5
10100
6
c 6
00100
7
c 7
00110
8
c 8
10110
9
c 9
11110
10
c 10
01110
11
c 11
01010
12
c 12
11010
13
c 13
10010
14
c 14
00010
15
c 15
00011
16
c 16
10011
17
c 17
11011
18
c 18
01011
19
c 19
01111
20
c 20
11111
21
c 21
10111
22
c 22
00111
23
c 23
00101
24
c 24
10101
25
c 25
11101
26
c 26
01101
27
c 27
01001
28
c 28
11001
29
c 29
10001
30
c 30
00001
31
c 31
BRIEF DESCRIPTION OF DRAWINGS
[0030] FIG. 1 is a diagram illustrating a wireless communication system according to an example embodiment;
[0031] FIG. 2 illustrates a format of a transmission frame according to an example embodiment;
[0032] FIG. 3 is a block diagram illustrating a transmitter according to an example embodiment;
[0033] FIGS. 4 through 6 are block diagrams illustrating examples of a transmitter according to another example embodiment;
[0034] FIGS. 7 through 9 illustrate examples of a transmission signal according to an example embodiment;
[0035] FIGS. 10 through 12 are block diagram illustrating examples of a receiver according to an example embodiment;
[0036] FIGS. 13 through 15 illustrate examples of detecting a binary data sequence according to an example embodiment;
[0037] FIG. 16 is a block diagram illustrating a transmitter according to another example embodiment;
[0038] FIG. 17 is a block diagram illustrating a receiver according to another example embodiment;
[0039] FIG. 18 is a flowchart illustrating a transmission method according to an example embodiment;
[0040] FIG. 19 is a flowchart illustrating a transmission method according to another example embodiment; and
[0041] FIGS. 20 through 23 are flowcharts illustrating a reception method according to an example embodiment.
DETAILED DESCRIPTION
[0042] Hereinafter, example embodiments will be described with reference to the accompanying drawings. Like reference numerals illustrated in the respective drawings refer to like elements throughout.
[0043] In the following example embodiments, various modifications may be made thereto. The following example embodiments are not construed as limited to the example embodiments and should be understood to include all changes, equivalents, and replacements within the technical scope of the example embodiments.
[0044] The terminology used herein is for the purpose of describing particular example embodiments only and is not to be used to limit the example embodiments. As used herein, the terms “a” and “the” are identical to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the terms “include,” “comprise,”, and “have” specify the presence of stated features, numbers, operations, elements, components, and/or combinations thereof, but do not preclude the presence or addition of one or more other features, numbers, operations, elements, components, and/or combinations thereof.
[0045] Unless otherwise defined, all terms, including technical and scientific terms, used herein have the same meaning as commonly understood by one of ordinary skill in the art to which these example embodiments pertain. Terms, such as those defined in commonly used dictionaries, are to be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art, and are not to be interpreted in an idealized or overlay formal sense unless expressly so defined herein.
[0046] Also, when describing with reference to the accompanying drawings, like reference numerals are assigned to like constituent elements and a repeated description related thereto is omitted. When it is determined that a detailed description related to a relevant known art may make the purpose of the example embodiments unnecessarily ambiguous, the detailed description will be omitted here.
[0047] FIG. 1 is a diagram illustrating a wireless communication system according to an example embodiment.
[0048] Referring to FIG. 1 , the wireless communication system may include a coherent transmitter 110 , noncoherent receivers 120 and 130 , and a coherent receiver 140 . The noncoherent receiver may be classified into a low selectivity noncoherent receiver 120 and a high selectivity noncoherent receiver 130 .
[0049] The coherent transmitter 110 may transmit data based on a packet unit. A packet may include payload or Physical Service Data Unit (PSDU) of the coherent transmitter 110 and the receivers 120 , 130 , and 140 . The payload may include data and a Cyclical Redundancy Check (CRC) that the coherent transmitter 110 is to transmit.
[0050] The coherent transmitter 110 may modulate the payload using a coherent modulation scheme. When a binary bit sequence is to be transmitted to the receivers 120 , 130 , and 140 using the coherent modulation scheme, the coherent transmitter 110 may map different bit sequences with a constant length to different code sequences and may transmit the mapped code sequences. Here, a length of a code sequence or a number of elements or alphabets of the code sequence may be greater than a length of a bit sequence. Also, the code sequence may include elements {−1, 0, +1}. According to an example embodiment, a sequence including elements {−1, 0, +1]} may be represented as a ternary sequence, a sequence including elements {0, +1} may be represented as a unipolar sequence, and a sequence including elements {−1, 1} may be represented as a bipolar sequence. Here, if a frequency of a carrier signal corresponding to the element +1 and a frequency of a carrier signal corresponding to the element −1 differ from each other, the element +1 may indicate setting a phase value of the carrier signal as zero degree, the element 0 may indicate setting OFF the carrier signal, and the element −1 may indicate setting the phase value of the carrier signal to be 180 degrees. Hereinafter, the term “phase” may be represented as an angular frequency. When the low selectivity noncoherent receiver 120 receives a packet from the coherent transmitter 110 , the low selectivity noncoherent receiver 120 may demodulate the payload based on a noncoherent demodulation scheme and thus, may not distinguish different phases of carrier signals. Since the low selectivity noncoherent receiver 120 may not distinguish the elements +1 and −1 from each other, the low selectivity noncoherent receiver 120 may recognize a ternary sequence as a unipolar sequence. The high selectivity noncoherent receiver 130 may distinguish different frequencies of carrier signals using a filter having a relatively high frequency selectivity or a relatively high Q-factor filter. Thus, the high selectivity noncoherent receiver 130 may distinguish elements +1 and −1 of a ternary sequence and may recognize the ternary sequence.
[0051] When the coherent receiver 140 receives a packet from the coherent transmitter 110 , the coherent receiver 140 may demodulate a payload using a coherent demodulation scheme, may distinguish different phases of received signals, and may recognize a ternary sequence, which differs from the low selectivity noncoherent receiver 120 .
[0052] Hereinafter, a method of designing a ternary sequence applicable e noncoherent receivers 120 and 130 and the coherent receiver 140 will be described.
[0053] Also, a method of transmitting and receiving a payload using the designed ternary sequence will be described with reference to FIGS. 2 through 15 .
[0054] <Design of Ternary Sequence>
[0055] System
[0056] During a process of designing a ternary sequence, the system may include a coherent transmitter, a coherent receiver, and a noncoherent receiver. The system may use the following elements.
[0057] a) Unipolar binary element (alphabet) {0, 1}
[0058] b) Ternary element {0, ±1}
[0059] A sequence/codeword including a ternary element may be represented as a ternary sequence/codeword. A sequence/codeword including a unipolar binary element may be represented as a unipolar binary sequence/codeword.
[0060] According to an example embodiment, a transmitter may extract a symbol from an M-ary element S. Here, S may denote S={0, 1, . . . , 2 k −1}, k=log 2 (M). Accordingly, an information rate may be k-bits/symbol. Before the transmitter performs transmission, each symbol extracted from S may be mapped to one of M possible waveforms or codewords from a spreading code C. Here, the term “spreading code” may also indicate a spreading factor or coefficient. That is, mapping of a symbol may be represented as m∈S c m ∈C={c 0 , . . . , c M−1 }. If N denotes a length of a codeword, an effective rate of a code or a spreading code may be represented as
[0000]
r
=
k
N
.
[0061] According to an example embodiment, a transmitted waveform corresponding to symbol m∈S, equivalently, c m ∈C may be represented as Equation 1.
[0000]
c
m
(
t
)
=
∑
n
=
0
Λ
-
1
c
m
[
n
]
g
(
t
-
n
T
c
)
.
[
Equation
1
]
[0062] In Equation 1, git denotes a chip waveform, !; denotes a chip, and T denotes a symbol section.
[0063] Under presumption of a constant weight code, or equal energy waveforms, a symbol detected at the receiver through matched filtering or correlation may be represented as Equation 2.
[0000]
m
^
=
argmax
m
∈
{
0
,
1
,
…
,
M
}
C
m
;
where
C
m
=
∫
0
T
y
(
t
)
c
m
(
t
)
t
[
Equation
2
]
[0064] In Equation 2, y(t) denotes a received waveform. y(t) may be deformed by additive white Gaussian noise (AWGN). {circumflex over (m)} may be defined as a symbol estimated at the receiver.
[0065] A symbol detection at the receiver may be carried out by performing correlation using a bank of M correlators that match M waveforms, respectively.
[0066] Code Design Condition:
[0067] When a ternary sequence/codeword is transmitted, the coherent receiver may recognize polarities of chips and may recognize the ternary sequence/codeword. On the contrary, the noncoherent receiver, for example, the receiver based on energy detection may recognize the ternary sequence/codeword as a unipolar binary sequence/codeword due to lack of phase information.
[0068] According to an example embodiment, a spreading code is to satisfy the followings.
[0069] 1) Sequences of a ternary code set C may be maximally separated.
[0070] 2) Sequences corresponding to a binary set |C| may be maximally separated.
[0071] Spreading Code Design for Ultra Low Power (ULF):
[0072] Due to a difference between a design of a coherent spreading code and a design of a noncoherent spreading code, the spreading code design for TAP may show aspects different from the aforementioned description. Hereinafter, an efficient spreading code design will he described.
[0073] Basic Definition and Concept:
[0074] Spreading codes for ULP may be acquired using two-level autocorrelation sequences. The two-level autocorrelation sequences may be used as a basis to acquire a coherent ternary code and a noncoherent binary code or an optical orthogonal code (OOC).
[0075] Ternary Sequence Having Perfect Periodic Autocorrelation:
[0076] A ternary sequence having perfect periodic autocorrelation and a length of N may have autocorrelation as expressed by Equation 3:
[0000]
R
^
x
,
x
(
k
)
=
{
N
if
k
_
=
0
0
if
λ
″
≠
0
mod
N
[
Equation
3
]
[0077] Two-Level Autocorrelation Sequence:
[0078] A binary sequence may be represented as {x 1 , x 2 , . . . , x N }, where x 1 ∈{0,1}. If the following condition of Equation 4 is met, the binary sequence may have two-level autocorrelation:
[0000] [Equation 4]
[0000]
R
^
x
,
x
(
k
)
=
{
N
if
k
=
0
A
if
k
≠
0
mod
N
[0079] In Equation 4, an autocorrelation function may be defined as
[0000]
R
^
(
k
)
=
∑
i
=
0
N
-
1
(
-
1
)
x
j
⊕
x
(
j
+
k
)
modN
.
[0000] If A=1, the binary sequence may be an ideal two-level autocorrelation sequence. Such sequences may serve as a bridge between a coherent ternary sequence and a noncoherent binary sequence. Many of the sequences may correspond to an m-sequence having a length of N=1 m −1 where m denotes an integer.
[0080] Cyclic Difference Set:
[0081] A difference set of A(n, k, λ) may be represented as D={d 1 , d 2 , . . . , d k }. Here, k denotes an integer. A number of solution pairs (d i , d j ) of elements of the difference set D may be λ, and a relationship between d i and d j may be represented as d 1 −d j ≡t(mod N). Here, t may be represented as 1≦t≦N−1.
[0082] The cyclic difference set may correspond to two-level autocorrelation sequences in one-to-one manner. Accordingly, the cyclic difference set may be used to design ternary sequences having the perfect autocorrelation.
[0083] Spreading Code for ULP:
[0084] The best method for completely synchronizing the system may include selecting sequences having an excellent autocorrelation attribute and assigning different cyclic shifts to different symbols.
[0085] Hereinafter, a method of designing shift equivalent codes of spreading codes 8, 16, and 32 will be described.
[0086] 1. Select an m-sequence with the period of N−1. Here, N denotes a target spreading code of a ternary code.
[0087] 2. Acquire the auric period of a ternary sequence from the m-sequence by converting elements of 1 and by maintaining elements of 0. It may be represented as a procedure A.
[0088] 3. Add the element 0 or 1 to a sequence in order to prevent damage to correlation of the sequence.
[0089] 4. The following two cases are possible based on the m-sequence and zero padding:
[0090] i) Balanced ternary sequence (from the m-sequence of weight N/2 or (N−2)/2)
[0091] ii) Unbalanced ternary sequence (all weights are (N−2)/2 or N/2+1)
[0092] The acquired ternary sequences may be characterized based on excellent correlation attributes. A set of spreading sequences to which different symbols are allocated may be acquired based on cyclic shifts of the acquired ternary sequences. According to an example embodiment, spreading codes 8, 16, and 32 may correspond to symbol sizes 3, 4, and 5, respectively.
[0093] Balanced Sequences Acquired from M-Sequences with the Weight of N/2
[0094] The following procedure may refer to a procedure of acquiring the balanced ternary sequence with the weight of N/2 from the m-sequence with the weight of N/2.
[0095] 1. Select the m-sequence with the weight of N/2.
[0096] 2. Acquire a tertiary sequence with the period of N−1 from the m-sequence with the period of N−1 using the procedure A if N=perfect square.
[0097] 3. Add the element of 0 to the acquired ternary sequence to minimize Mean Squared AutoCorrelation (MSAC). Here, the MSAC may be defined as Equation 5.
[0000]
μ
MSAC
=
1
(
N
-
1
)
∑
τ
=
1
N
-
1
R
(
τ
)
2
[
Equation
5
]
[0098] In Equation 5, R(τ) denotes autocorrelation normalized at the period of a sequence in delay τ, and may be defined as Equation 6.
[0000] [Equation 6]
[0000]
R
(
τ
)
=
1
/
w
∑
n
=
0
N
-
1
C
n
C
n
+
τ
[0099] In Equation 6, w denotes a hamming weight of a sequence. Balanced sequences acquired from a representative m-sequence with the weight of N/2 may be represented as Table 1.
[0000]
TABLE 1
Period
Basic Ternary spreading sequence
Base sequence
μ coherent
μ non-coherent
8
1
1
−1
0
1
1
−1
0
0
1
0
0.0536
0.1964
0
1
0
0; 0
1
1
−1
0
0
1
0; 1
0
1
1
−1
0
0
0; 0
1
0
1
1
−1
0
0; 0
0
1
0
1
1
−1
0
16
1
1
0
0
0
1
1
−1
1
0.0250/
0.2250/
−1
0
0
0
0
1
0
1
1
0
0.0375
0.2208
1
1
−1
1
0
−1
0
0
0
1
0
0; 0
1
1
−1
1
0
1
0
1
1
0
0
−1
0
0
0
0
1
1
1
0
1
1
1
1
0
−1
0.0125
0.2208
1
0
−1
0
0
1
−1
0
0
1
0
0
1
−1
0
0
1
0
0
0
32
1
1
−1
1
−1
0
0
1
0
1
1
0
0.0111
0.2359
−1
0
0
0
0
1
1
−1
1
−1
0
0
1
1
0
1
0
1
1
0
1
−1
−1
0
−1
−1
0
1
1
0
−1
0
0
0
0
0
−1
0
0
0
0
−1
0
0
1
0
1
1
0
0
0
[0100] According to an example embodiment, other m-sequences may be replaced with base sequences.
[0101] Balanced Sequences Acquired from M-Sequences with the Weight of (N−2)/2
[0102] The following procedure may refer to a procedure of acquiring the balanced ternary sequence with the weight of N/2 from the m-sequence with the weight of (N−2)/2.
[0103] 1. Acquire a ternary sequence with the period of N−1 from the m-sequence. A perfect ternary sequence with the weight of (N−2)/2 may be absent. Accordingly, a procedure B may be employed to deduce a ternary sequence having an excellent correlation attribute from a ternary element.
[0104] 2. Add the element of 1 to the acquired ternary sequence to minimize MSAC.
[0105] 3. Result sequences may be characterized by the weight of N/2.
[0106] Balanced sequences acquired from the representative in-sequence with the weight of (N−2)/2 may be represented as Table 2.
[0000]
TABLE 2
Period
Basic Ternary spreading sequence
Base sequence
μ coherent
μ non-coherent
8
0
0
0
1
0
0
0
1
−1
0
1
0.0536
0.1964
−1
0
1
1; 1
0
0
0
1
−1
0
1
16
−1
0
0
0
−1
0
0
0
0
1
0
−1
0
0.0125
0.2208
0
1
0
−1
0
1
1
0
1
1
0
0
1
1
0
1
1
1; 1
−1
0
0
0
0
1
0
−1
0
0
1
1
0
1
1; 1
1
−1
0
0
0
0
1
0
−1
0
0
1
1
0
1
32
−1
0
0
1
0
−1
−1
1
−1
0
1
0
0.0131
0.2359
0
1
−1
0
1
0
0
0
1
0
0
1
1
−1
−1
−1
1
−1
0
0
0
0
0
1
−1
0
0
0
1
0
1
1
0
1
−1
0
0
0
1
0
0
1
1
−1
0
0
0
0
0
1
1
[0107] According to an example embodiment, other m-sequences may be replaced with base sequences.
[0108] Consolidated List
[0109] To deduce sequences of Table 3, a sequence in which elements of 0 and elements aside from 0 are uniformly distributed may be selected from Table 1 and Table 2.
[0000]
TABLE 3
Basic Ternary
Period
spreading sequence
Base sequence
μ coherent
μ non-coherent
8
0
0
0
1
−1
0 0 0 1 −1 0 1
0.0536
0.1964
0
1
1
16
1
−1
0
0
0
−1 0 0 0 0 1 0
0.0125
0.2208
0
1
0
−1
0
−1 0 0 1 1 0
0
1
1
0
1
1 1
1
32
−1
0
0
1
0 −1 −1 1 −1 0
0.0131
0.2359
0
1
−1
0
−1
1 0 1 0 0 0 1 0
−1
1
−1
0
0 1 1 −1 0 0 0
1
0
1
0
0
0 0 1 −1 0 0 1
0
1
0
0
1
0 1 −1
1
−1
0
0
0
0
0
1
1
[0110] Base ternary spreading sequences of Table 3 may be used to encode data symbols for transmission through a wireless channel. Spreading sequences to encode data symbols may be acquired through a cyclic shift of a single base ternary spreading sequence of Table 3. Accordingly, a number of distinct spreading sequences may be equal to a spreading code. Spreading sequences of a spreading code M may be used to encode data symbols with the size of k=log 2 M. For example, a spreading sequence of the spreading code M=8 may be used to encode a data symbol with the size of k=log 2 8=3.
[0111] Also, spreading sequences of spreading codes 16 and 32 may be used to encode data symbols with the sizes of 4 and 5, respectively. In Table 3, the basic ternary spreading sequences may be represented as 3/8-OOK, 4/16-OOK, and 5/32-OOK, respectively. Table 4 shows an example in which the basic ternary sequences of Table 3 are classified into 3/8-OOK, 4/16-OOK, and 5/32-OOK.
[0000]
TABLE 4
Basic Ternary
k
M
Nomenclature
spreading sequence
3
8
⅜-OOK
0
0
0
1
−1
0
1
1
4
16
4/16-OOK
1
−1
0
0
0
0
1
0
−1
0
0
1
1
0
1
1
5
32
5/32-OOK
−1
0
0
1
0
1
−1
0
−1
−1
1
−1
0
1
0
1
0
0
0
1
0
0
1
1
−1
0
0
0
0
0
1
1
[0112] According to an example embodiment, data symbols may be allocated to spreading codes based on a customized logic, for example, grey coding. Table 5 shows a representative example in which data symbols corresponding to k=3 and M=8 are allocated to spreading codes. Here, a cyclic shift of an original sequence may be a decimal equivalent of a binary data symbol.
[0000]
TABLE 5
Cyclic shift
(Decimal
Data-symbol
equivalent)
Spreading sequence
000
0
0
0
0
1
−1
0
1
1
001
1
1
0
0
0
1
−1
0
1
010
2
1
1
0
0
0
1
−1
0
011
3
0
1
1
0
0
0
1
−1
100
4
−1
0
1
1
0
0
0
1
101
5
1
−1
0
1
1
0
0
0
110
6
0
1
−1
0
1
1
0
0
111
7
0
0
1
−1
0
1
1
0
*Maximum length shift register sequence (m-sequence)
[0113] An m-sequence or a maximum length sequence may belong to a general grade of a two-level autocorrelation sequence and may be present for all of N=2 m −1 where in denotes an integer. The m-sequence may be generated using a linear feedback shifter register (LFSR) having a primitive polynomial feedback. Such sequence may correspond to a maximum period acquired from a given length LFSR.
[0114] Advantages in the Case of Applying an M-Sequence to a Sequence Design:
[0115] Using the m-sequence to design spreading sequences may be advantageous for all of coherent and noncoherent.
[0116] In view of the noncoherent, using the m-sequence may have the following advantages:
[0117] 1) The m-sequence may correspond to a cyclic difference set in a form of □m−1, 2m−1, 2m−2}.
[0118] 2) It may indicate a constant in phase autocorrelation of (N+1)/4 of a unipolar binary element {0, 1}.
[0119] In view of the coherent, using the m-sequence may have the following advantages:
[0120] 1) If m-sequence=perfect square, a perfect sequence of elements {0, −1, 1} may he generated from the m-sequence, for example, the procedure A to maintain the element of 0.
[0121] 2) Perfect sequences with the periods of 7 and 31 may be acquired.
[0122] 3) Such sequence may be expanded based on zero padding and a correlation attribute may not be damaged. The result thereof may be represented as sequences with the periods of 8 and 32. A ternary sequence close to perfection may be acquired for a spreading code 15 through the procedure B by the aforementioned method.
[0123] Procedure A: Acquires a Perfect Ternary Sequence from an M-Sequence:
[0124] If x and y are two ideal two-level autocorrelation sequences, u sequence {θ(x,y)+1} may be a perfect sequence including an element of 0 in phase autocorrection. Here, θ(x,y) denotes a cross-correlation sequence between sequences x and y. If two sequences are selected as a preferred pair among m-sequences, a result thereof, that is, {θ(x,y)+1} may be ternary. For example, if preferred pair=
[0000]
θ
(
x
,
y
)
∈
{
-
1
,
-
1
+
2
n
+
1
2
,
-
1
,
-
2
n
+
1
2
}
,
[0000] it may be represented as
[0000]
θ
(
x
,
y
)
+
1
∈
{
0
,
±
2
n
+
1
2
}
.
[0000] A result acquired by dividing
[0000]
{
θ
(
x
,
y
)
+
1
}
by
2
n
+
1
2
[0000] may be represented as a sequence including elements {0, ±1}.
[0125] Procedure B: Acquires a Ternary Sequence Close to Perfection from an M-Sequence.
[0126] A perfect ternary sequence may be present if a weight of a sequence is a perfect square. Accordingly, a perfect ternary sequence having a period of 15 may be absent. In this case, a ratio between elements of −1 and elements of +1 in the perfect ternary sequence may be a value between 1/3 and 2/3. Accordingly, the ternary sequence close to perfection may be acquired based on the ratio. A sequence having a smallest MSAC value may be selected. The MSAC may be defined as Equation 7.
[0000]
μ
MSAC
=
1
(
N
-
1
)
∑
τ
=
1
N
-
1
R
(
τ
)
2
[
Equation
7
]
[0127] In Equation 7, R(τ) denotes periodic autocorrelation of a sequence in delay τ.
[0128] <Transmission and Reception of Ternary Payload Sequence>
[0129] FIG. 2 illustrates a format of a transmission frame according to an example embodiment.
[0130] Referring to FIG. 2 , a transmission frame 200 may include a preamble 210 , a start frame delimiter (SFD) 220 , a physical layer header (PHR) 230 , and a physical service data unit (PSDU) 240 . In one example embodiment, a packet may be used as the same meaning as the transmission frame 200 .
[0131] The preamble 210 may be a bitstream recorded at the head of the transmission frame 200 . The preamble 210 may include a specific bit-pattern for time synchronization.
[0132] The SFD 220 may identify a beginning of a frame, and may identify reconfirmation of synchronization. Also, the SFD 220 may indicate a field for acquiring frame synchronization.
[0133] The PHR 230 may be a field that indicates useful information associated with a physical layer For example, information may be information about a length indicator, a used modulation scheme, and a used encoding scheme. Also, the PHR 230 may include a header check sequence (WS) and a field about a format of the PSDU 240 . Here, the HCS may he used to determine whether an error has occurred in the PHR 230 .
[0134] The PSDU 240 may be a unit of data transferred from an upper layer of the physical layer and not encoded in a format of bits. The PSDU 240 may include data that is substantially transmitted and received in the upper layer of the physical layer. The PSDU 240 may be expressed as a payload.
[0135] FIG. 3 is a block diagram illustrating a transmitter according to an example embodiment.
[0136] Referring to FIG. 3 , a transmitter 300 may include a first signal converter 310 and a second signal converter 320 . Here, the transmitter 300 may indicate the coherent transmitter 110 of FIG. 1 . Hereinafter, a scheme in which a transmitter converts a binary data sequence to a first signal and a second signal may also be referred to as a ternary amplitude shift keying (TASK) scheme, a ternary frequency shift keying (TFSK) scheme, or an ON-OFF FSK scheme.
[0137] The first signal converter 310 may convert a ternary payload sequence including elements of −1, 0, or 1 to the first signal. In one example embodiment, elements may be represented using an alphabet or a chip.
[0138] The first signal converter 310 may include a ternary sequence mapper and a converter. The ternary sequence mapper may generate a ternary payload sequence by mapping a pre-designed ternary sequence to a binary data sequence. In one example embodiment, the ternary sequence mapper may generate a ternary payload sequence by dividing a binary data sequence including elements of 0 or 1 based on a predetermined length, and by mapping a pre-designed ternary sequence to the divided binary data sequence. Here, the pre-designed ternary sequence may indicate a ternary sequence extracted during the aforementioned ternary sequence design process. Also, the pre-designed ternary sequence may be pre-stored in the transmitter 300 . For example, the pre-designed ternary sequence may be stored in a lookup table.
[0139] According to an example embodiment, in the case of using a 3/8 TASK modulation scheme, a ternary sequence mapped to a binary data sequence may be shown as in Table 6.
[0000]
TABLE 6
Binary data sequence
Data symbol
Ternary sequence
3-tuple
m ∈
c m ∈
000
0
c 0
100
1
c 1
110
2
c 2
010
3
c 3
011
4
c 4
111
5
c 5
101
6
c 6
001
7
c 7
[0140] In Table 6, C 0 denotes a sequence of [0 0 0 1 −1 0 1 1] and C m denotes a sequence acquired by cyclic shifting C 0 to right by m. Here, m denotes an integer between 1 and 7. For example, C 1 may denote a sequence of [1 0 0 0 1 −1 0 1] and C 2 may denote a sequence of [1 1 0 0 0 1 −1 0].
[0141] In the case of using a 5/32 TASK modulation scheme, a ternary sequence mapped to a binary data sequence may be shown as in Table 7.
[0000]
TABLE 7
Binary data sequence
Data symbol
Ternary sequence
5-tuple
m ∈
c m ∈
00000
0
c 0
10000
1
c 1
11000
2
c 2
01000
3
c 3
01100
4
c 4
11100
5
c 5
10100
6
c 6
00100
7
c 7
00110
8
c 8
10110
9
c 9
11110
10
c 10
01110
11
c 11
01010
12
c 12
11010
13
c 13
10010
14
c 14
00010
15
c 15
00011
16
c 16
10011
17
c 17
11011
18
c 18
01011
19
c 19
01111
20
c 20
11111
21
c 21
10111
22
c 22
00111
23
c 23
00101
24
c 24
10101
25
c 25
11101
26
c 26
01101
27
c 27
01001
28
c 28
11001
29
c 29
10001
30
c 30
00001
31
c 31
[0142] In Table 7, C 0 denotes a sequence of [−1 0 0 1 0 1 −1 0 −1 −1 1 −1 0 1 0 1 0 0 0 1 0 0 1 1 −1 0 0 0 0 0 1] and (̂ denotes a sequence acquired by cyclic shifting C 0 to right by m. Here, m denotes an integer between 1 and 31.
[0143] According to an example embodiment, the ternary sequence mapper may search Table 6 or Table 7 for a ternary sequence corresponding to a binary data sequence, may extract the retrieved ternary sequence as a pre-designed ternary sequence, and may map the pre-designed ternary sequence to the binary data sequence.
[0144] The converter may modulate a ternary payload sequence using a TASK modulation scheme, and may convert the ternary payload sequence, or a chip sequence of a payload, or a chip sequence of a PPM, to a first signal.
[0145] According to an example embodiment, the converter may modulate a ternary payload sequence using an amplitude shift keying (ASK) modulation scheme. Here, the converter may map the ternary payload sequence as shown in Equation 8.
[0000]
A
n
=
{
+
A
when
d
(
n
)
=
+
1
0
when
d
(
n
)
=
0
-
A
when
d
(
n
)
=
-
1
[
Equation
8
]
[0146] In Equation 8, {d(n)} denotes the ternary payload sequence, A n denotes an amplitude of an n th element or chip, and A denotes a transmission voltage level. Gaussian pulse shaping may be employed for the ASK modulation scheme. The respective elements of the ternary payload sequence may be generated at rates of 1 Mchip/s for 2.4 GHz band; 600 Kchips/s for 780 MHz, 863 MHz, 900 MHz and 950 MHz bands; and 250 Kchips/s for 433 MHz and 470 MHz bands.
[0147] Also, the first signal converter 310 may include a pulse shaping filter. The pulse shaping filter may sequentially receive elements of the ternary payload sequence, thereby enabling a shape of the first signal of a baseband to be smoothly changed instead of being suddenly changed on a time axis. Accordingly, the pulse shaping filter may adjust a frequency hand of the first signal not to be widely distributed.
[0148] According to an example embodiment, the pulse shaping filter may adjust a transmit power spectrum. The pulse shaping filter may approximate an ideal Gaussian pulse having a section of T and BT of 0.3 to 0.5. An impulse response of the pulse shaping filter may be represented as Equation 9.
[0000]
g
(
t
)
=
B
2
π
ln
(
2
)
-
(
2
π
B
2
t
2
l
(
2
)
)
[
Equation
9
]
[0149] Also, the first signal modulated from the ternary payload sequence may be represented as Equation 10.
[0000]
x
BB
(
t
)
=
A
∑
n
=
]
⌊
W
pp
DU
d
(
n
)
g
(
t
-
nT
chip
)
[
Equation
10
]
[0150] In Equation 10, d(n)∈{−1, 0, 1} denotes an element of the ternary payload sequence, T chip denotes a section of the first signal corresponding to the element, and N PPDU denotes a number of elements of the ternary payload sequence. Elements of the ternary payload sequence may be represented as Equation 11.
[0000]
[
d
(
1
)
,
…
,
d
(
N
PPDU
)
]
=
[
{
c
pre
(
1
)
,
…
,
c
pre
(
N
p
)
}
,
{
c
SFD
(
1
)
,
…
,
c
SFD
(
N
S
)
}
,
{
c
PHR
(
1
)
,
…
,
c
PHR
(
N
R
)
}
,
{
c
(
1
)
,
…
,
c
(
N
D
)
}
]
[
Equation
11
]
[0151] In Equation 11,
[0000]
{
c
bLG
(
!
)
,
…
(
)
}
[0000] denotes a chip sequence that configures a preamble field,
[0000]
{
c
SFD
,
…
,
cSFD
(
N
s
)
}
[0000] denotes a chip sequence that configures a spreading SFD field, {C PHR (1), . . . , C PHR (iŶ)} denotes a chip sequence that configures a spreading PHR field, and {c(1), . . . , c(N D )} denotes a chip sequence that configures an encoded ternary sequence spreading PSDU field.
[0152] A pass band of the first signal modulated from the ternary payload sequence may be represented as Equation 12.
[0000]
x
PB
(
t
)
=
[
A
∑
n
=
1
N
PPDU
d
(
n
)
g
(
t
-
nT
chip
)
]
cos
(
ω
c
t
+
φ
)
[
Equation
12
]
[0153] In Equation 12, ω c denotes an angular frequency of a carrier signal and φ∈[0,2π] denotes a random phase.
[0154] Also, the second signal converter 320 may convert the first signal to a second signal by converting each section of the first signal based on an element of the ternary payload sequence. The second signal converter 320 may include a zero-value converter configured to convert a section corresponding to an element of 0 in the first signal and an absolute one value converter configured to convert a section corresponding to an element of 1 and a section corresponding to element of −1 in the first signal.
[0155] The zero-value converter may convert the section corresponding to the element of 0 in the first signal using a zero-value detector and an ON-OFF controller. The zero-value detector may detect the section corresponding to the element of 0 in the first signal. For example, the zero-value detector may detect a section in which an amplitude of the first signal is close to 0 as the section corresponding to the element of 0. The ON-OFF controller may turn OFF an output of the section corresponding to the element of 0 detected at the zero-value detector. Accordingly, an amplitude value of a section corresponding to the element of 0 in the second signal may be zero.
[0156] Further, the absolute one value converter my detect the section corresponding to the element of 1 and the section corresponding to the element of −1 in the first signal, and may convert the section corresponding to the element of 1 and the section corresponding to the element of −1 by applying different conversion schemes.
[0157] According to an example embodiment, the absolute one value converter may detect the section corresponding to the element of 1 and the section corresponding to the element of −1 in the first signal using an absolute value detector and a sign detector. The absolute value detector may detect a section corresponding to an element of an absolute one value in the first signal, for example, a section in which an amplitude of the first signal is greater than or equal to a threshold value, as the section corresponding to the element of the absolute one value. The sign detector may detect a signal of the element of the absolute one value and may classify the section corresponding to the element of the absolute one value into the section corresponding to the element of 1 and the section corresponding to the element of −1. For example, the sign detector may detect a section corresponding to a phase of zero degrees as the section corresponding to the element of 1 and a section corresponding to a phase of 180 degrees as the section corresponding to the element of −1, in the section corresponding to the element of the absolute one value.
[0158] Also, the absolute one value converter may convert the selection corresponding to the element of and the section corresponding to the element of −1 using a frequency shifter or/and a phase shifter. For example, when transmitting a second signal to a noncoherent receiver, the absolute one value converter may convert the section corresponding to the element of 1 and the section corresponding to the element of −1 using the frequency shifter. When transmitting a second signal to a coherent receiver, the absolute one value converter may convert the section corresponding to the element of 1 and the section corresponding to the element of −1 using all of the frequency shifter and the phase shifter.
[0159] The frequency shifter may shift a frequency of the section corresponding to the element of 1 in the first signal to a frequency f 1 , and may shift a frequency of the section corresponding to the element of −1 in the first signal to a frequency f 2 .
[0160] For example, when converting the section corresponding to the element of 1 in the first signal, the frequency shifter may shift a frequency of a carrier signal adjusted by voltage controlled oscillation (VCO) to a frequency and the absolute one value converter may multiply the carrier signal shifted to the frequency f 1 by an absolute value of an amplitude of the section corresponding to the element of 1. Also, the frequency shifter may shift, to the frequency f 1 , a frequency of a carrier signal having an envelope corresponding to a value that is proportional to the absolute value of the amplitude of the section corresponding to the element of 1. As another example, when converting the section corresponding to the element of −1 in the first signal, the frequency shifter may shift a frequency of a carrier signal adjusted by VCO to a frequency f 2 , and the absolute one value converter may multiply the carrier signal shifted to the frequency f 2 by an absolute value of an amplitude of the section corresponding to the element of −1. Also, the frequency shifter may shift, to the frequency f 2 , a frequency of a carrier signal having an envelope corresponding to a value that is proportional to the absolute value of the amplitude of the section corresponding to the element of −1. According to an example embodiment, the frequency f 1 and the frequency f 2 may have different frequency bands. For example, the frequency f 2 may be mater than the frequency f 1 .
[0161] Also, the phase shifter may shift a phase of the section corresponding to the element of 1 in the first signal to a phase θ 1 , and may shift a phase of the section corresponding to the element of −1 to a phase θ 2 . For example, the phase shifter may shift a phase of a carrier signal to zero degrees, and the absolute one value converter may multiply the carrier signal shifted to zero degrees by an absolute value of an amplitude of the section corresponding to the element of 1. Also, the phase shifter may shift, to zero degrees, a phase of a carrier signal having an envelope corresponding to a value that is proportional to the absolute value of the amplitude of the section corresponding to the element of 1. As another example, the phase shifter may shift a phase of a carrier signal to 180 degrees, and the absolute one value converter may multiply the carrier signal shifted to 180 degrees by an absolute value of an amplitude of the section corresponding to the element of −1. Also, the phase shifter may shift, to 180 degrees, a phase of a carrier signal having an envelope corresponding to a value that is proportional to the absolute value of the amplitude of the section corresponding to the element of −1.
[0162] According to an example embodiment, the phase shifter may shift, to the phase θ 1 , a phase of the section corresponding to the element of 1 shifted to the frequency f 1 by the frequency shifter, and may shift, to the phase θ 2 , a phase of the section corresponding to the element of −1 shifted to the frequency f 2 by the frequency shifter.
[0163] Also, the second signal converter 320 may include an amplifier. The amplifier may amplify an amplitude of the converted second signal. The transmitter 300 may transmit the amplified second signal to the noncoherent receiver or the coherent receiver via an antenna.
[0164] FIGS. 4 through 6 are block diagrams illustrating examples of a transmitter according to another example embodiment.
[0165] Referring to FIG. 4 , a transmitter 400 may transmit data to a low selectivity noncoherent receiver, a high selectivity noncoherent receiver, or a coherent receiver. The transmitter 400 may include a first signal converter 410 and a second signal converter 420 . The first signal converter 410 may include a ternary sequence mapper 411 and a pulse shaping filter 412 .
[0166] The ternary sequence mapper 411 may generate a ternary payload sequence by dividing a binary data sequence including elements of 0 or 1 based on a predetermined length, and by mapping a pre-designed ternary sequence to the divided binary data sequence. For example, if a binary data sequence of [1 0 1 0 0 1 1 1 0] is input to the ternary sequence mapper 411 , the ternary sequence mapper 411 may divide the binary data sequence into [1 0 1], [0 0 1], and [1 1 0]. The ternary sequence mapper 411 may map the pre-designed ternary sequence to the divided binary data sequence. For example, if a pre-designed ternary sequence corresponding to a divided binary data sequence [1 0 1] is [0 1 −1 0 1 1 0 0], the ternary sequence mapper 411 may generate a ternary payload sequence [0 1 −1 0 1 1 0 0] by mapping the ternary sequence [0 1 −1 0 1 1 0 0] to the divided binary sequence [1 0 1]. Also, the ternary sequence mapper 411 may modulate a ternary payload sequence to a first signal.
[0167] Also, the ternary sequence mapper 411 may modulate the ternary payload sequence using an ASK modulation scheme. According to an example embodiment, the ternary sequence mapper 411 may include the converter of FIG. 3 . For example, when modulating a ternary payload sequence [0 1 −1 0 1 1 0 0] to a first signal, an amplitude of a section of the first signal corresponding to 0 of the ternary payload sequence may be zero, an amplitude of a section of the first signal corresponding to 1 may have a positive value, and an amplitude of a section of the first signal corresponding to −1 may have a negative value.
[0168] The pulse shaping filter 412 may sequentially receive elements of the ternary payload sequence and may adjust a frequency band of the first signal not to be widely distributed.
[0169] The second signal converter 420 may include a zero-value converter 430 , an absolute one value converter 440 , and an amplifier 450 .
[0170] The zero-value converter 430 may include a zero-value detector 431 and an ON-OFF controller 432 . The zero-value detector 431 may detect a section in which an amplitude of the first signal is less than a threshold value as a section corresponding to an element of 0. Here, the threshold value may denote a magnitude of noise of the first signal. The ON-OFF controller 432 may turn OFF output of the section corresponding to the element of 0 detected at the zero-value detector 431 .
[0171] The absolute one value converter 440 may include an absolute value detector 441 , a sign detector 442 , a VCO 443 , a frequency shifter 444 , and a calculator 445 .
[0172] The absolute value detector 441 may detect a section in which an amplitude of the first signal is greater than or equal to a threshold value as a section corresponding to an element of an absolute one value. The sign detector 442 may detect a signal of the element of the absolute one value and may classify the section corresponding to the element of the absolute one value into the section corresponding to the element of 1 and the section corresponding to the element of −1. For example, the sign detector 442 may detect a section corresponding to a phase of zero degrees in the section corresponding to the element of the absolute one value as the section corresponding to the element of 1, and may detect the section corresponding to a phase of 180 degrees as the section corresponding to the element of −1.
[0173] The VCO 443 may adjust a frequency of a carrier signal. The frequency shifter 444 may shift a frequency of a carrier signal of the section corresponding to the element of 1 to a frequency f 1 , and may shift a frequency of a carrier signal of the section corresponding to the element of −1 to a frequency f 2 .
[0174] The calculator 445 may generate a second signal by multiplying carrier signal shifted to the frequency f 1 by an absolute value of an amplitude of the section corresponding to the element of 1 and by multiplying the carrier signal shifted to the frequency f 2 by an absolute value of an amplitude of the section corresponding to the element of −1.
[0175] The amplifier 450 may amplify an amplitude of the second signal. The transmitter 400 may transmit the amplified second signal to the noncoherent receiver or the coherent receiver via an antenna.
[0176] Referring to FIG. 5 , a transmitter 500 may transmit data to a low selectivity noncoherent receiver, a high selectivity noncoherent receiver, or a coherent receiver. The transmitter 500 may include a first signal converter 510 and a second signal converter 520 . The first signal converter 510 may include a ternary sequence mapper 511 and a pulse shaping filter 512 .
[0177] The ternary sequence mapper 511 may generate a ternary payload sequence by receiving a binary data sequence including elements of 0 or 1, by dividing the binary data sequence based on a predetermined length, and by mapping a pre-designed ternary sequence to the divided binary data sequence.
[0178] Also, the first signal converter 510 may generate a first signal by modulating the ternary payload sequence. According to an example embodiment, the ternary sequence mapper 511 may include the converter of FIG. 3 .
[0179] The pulse shaping filter 512 may sequentially receive elements of the ternary payload sequence and may adjust a frequency band of the first signal not to be widely distributed.
[0180] The second signal converter 520 may include a zero-value converter 530 , an absolute one value converter 540 , and an amplifier 550 .
[0181] The zero-value converter 530 may include a zero-value detector 531 and an ON-OFF controller 532 . The zero-value detector 531 may detect a section in which an amplitude of the first signal is less than a threshold value as a section corresponding to an element of 0. Here, the threshold value may denote a magnitude of noise of the first signal. The ON-OFF controller 532 may turn OFF output of the section corresponding to the element of 0 detected at the zero-value detector 531 .
[0182] The absolute one value converter 540 may include an absolute value detector 541 , a sign detector 542 , a phase shifter 543 , and a calculator 544 .
[0183] The absolute value detector 541 may detect a section in which an amplitude of the first signal is greater than or equal to a threshold value as a section corresponding to an element of an absolute one value. The sign detector 542 may detect a sign of the element of the absolute one value and may classify the section corresponding to the element of the absolute one value into a section corresponding to an element of 1 and a section corresponding to an element of −1.
[0184] The phase shifter 543 may shift a phase of a carrier signal of the section corresponding to the element of 1 to a first phase and may shift a phase of a carrier signal of the section corresponding to the element of −1 to a second phase, in the first signal.
[0185] The calculator 544 may generate a second signal by multiplying the carrier signal shifted to the first phase by an absolute value of an amplitude of the section corresponding to the element of 1 and by multiplying the carrier signal shifted to the second phase by an absolute value of an amplitude of the section corresponding to the element of −1.
[0186] The amplifier 550 may amplify an amplitude of the second signal. The transmitter 500 may transmit the amplified second signal to the noncoherent receiver or the coherent receiver via an antenna.
[0187] Referring to FIG. 6 , a transmitter 600 may transmit data to a low selectivity noncoherent receiver, a high selectivity noncoherent receiver, or a coherent receiver. The transmitter 600 may include a first signal converter 610 and a second signal converter 620 . The first signal converter 610 may include a ternary sequence mapper 611 and a pulse shaping filter 612 .
[0188] The ternary sequence mapper 611 may generate a ternary payload sequence by receiving a binary data sequence including elements of 0 or 1, by dividing the ternary payload sequence based on a predetermined length, and by mapping a pre-designed ternary sequence to the divided binary data sequence.
[0189] Also, the first signal converter 610 may generate a first signal by modulating the ternary payload sequence. According to an example embodiment, the ternary sequence mapper 611 may include the converter of FIG. 3 .
[0190] The pulse shaping filter 612 may sequentially receive elements of the ternary payload sequence and may adjust a frequency band of the first signal not to be widely distributed.
[0191] The second signal converter 620 may include a zero-value converter 630 , an absolute one value converter 640 , and an amplifier 650 .
[0192] The zero-value converter 630 may include a zero-value detector 631 and an ON-OFF controller 632 . The zero-value detector 631 may detect a section in which an amplitude of the first signal is less than a threshold value as a section corresponding to an element of 0. Here, the threshold value may denote a magnitude of noise of the first signal. The ON-OFF controller 632 may turn OFF output of the section corresponding to the element of 0 detected at the zero-value detector 631 .
[0193] The absolute one value converter 640 may include an absolute value detector 641 , a sign detector 642 , a VCO 643 , a frequency shifter 644 , a phase shifter 645 , and a calculator 646 .
[0194] The absolute value detector 641 may detect a section in which an amplitude of the first signal is greater than or equal to a threshold value as a section corresponding to an element of an absolute one value. The sign detector 642 may detect a sign of the element of the absolute one value and may classify the section corresponding to the element of the absolute one value into a section corresponding to an element of 1 and a section corresponding to an element of −1.
[0195] The VCO 643 may adjust a frequency of a carrier signal. The frequency shifter 644 may shift a carrier signal of the section corresponding to the element of 1 to a frequency f 1 , and may shift a carrier signal of the section corresponding to the element of −1 to a frequency f 2 . The phase shifter 645 may shift, to a phase θ 1 , a phase of the carrier signal shifted to the frequency f 1 at the frequency shifter 644 and may shift, to a phase θ 2 , a phase of the carrier signal shifted to the frequency f 2 at the frequency shifter 644
[0196] The calculator 646 may generate a second signal by multiplying the carrier signal shifted to the frequency f 1 and the phase θ 1 by an absolute value of an amplitude of the section corresponding to the element of 1, and by multiplying the carrier signal shifted to the frequency f 2 and the phase θ 2 by an absolute value of an amplitude of the section corresponding to the element of −1.
[0197] The amplifier 650 may amplify an amplitude of the second signal. The transmitter 600 may transmit the amplified second signal to the low selectivity noncoherent receiver, the high selectivity noncoherent receiver, or the coherent receiver via an antenna.
[0198] FIGS. 7 through 9 illustrate examples of a transmission signal according to an example embodiment.
[0199] Referring to FIG. 7 , a transmitter may modulate a binary data sequence, and may transmit the modulated binary data sequence to a low selectivity noncoherent receiver, a high selectivity noncoherent receiver, or a coherent receiver. When a binary data sequence 710 is transmitted to the transmitter, the transmitter may generate a first signal by mapping, to the binary data sequence 710 , a ternary sequence 720 that is preset to correspond to the binary data sequence 710 , and by modulating the ternary sequence 720 . The transmitter may input the first signal to a pulse shaping filter and may adjust a frequency band of the first signal not to be widely distributed. In a pulse shaping filter output signal 730 , an amplitude of a section corresponding to an element of 1 may have a positive value, an amplitude of a section corresponding to an element of −1 may have a negative value, and an amplitude of a section corresponding to an element of 0 may be zero.
[0200] In the pulse shaping filter output signal 730 , the transmitter may shift a frequency of a carrier signal of the section corresponding to the element of 1 to a frequency f 1 , and may shift a frequency of a carrier signal of the section corresponding to the element of −1 to a frequency f 2 . Here, an amplitude of the second frequency may be greater than an amplitude of the first frequency. Also, the transmitter may generate a second signal by multiplying the carrier signal shifted to the frequency f 1 by an absolute value of an amplitude of the section corresponding to the element of 1 and by multiplying the carrier signal shifted to the frequency f 2 by an absolute value of an amplitude of the section corresponding to the element of −1. The transmitter may amplify the second signal by inputting the second signal to an amplifier. In an amplified second signal 740 , a frequency of the section corresponding to the element of 1 may be distinguished from a frequency of the section corresponding to the element of −1. An output of the section corresponding to the element of 0 may be zero. The transmitter may transmit the amplified second signal 740 to the low selectivity noncoherent receiver and the high selectivity noncoherent receiver.
[0201] Referring to FIG. 8 , a transmitter may modulate a binary data sequence, and may transmit the modulated binary data sequence to a low selectivity noncoherent receiver, a high selectivity noncoherent receiver, or a coherent receiver. When a binary data sequence 810 is input to the transmitter, the transmitter may generate a first signal by mapping, to the binary data sequence 810 , a ternary sequence 820 that is preset to correspond to the binary data sequence 810 , and by modulating the ternary sequence 820 . The transmitter may input the first signal to a pulse shaping filter and may adjust a frequency band of the first signal not to be widely distributed. In a pulse shaping filter output signal 830 , an amplitude of a section corresponding to an element of 1 may have a positive value, an amplitude of a section corresponding to an element of −1 may have a negative value, and an amplitude of a section corresponding to an element of 0 may be zero.
[0202] In the pulse shaping filter output signal 830 , the transmitter may shift a phase θ 2 carrier signal of the section corresponding to the element of 1 to a phase θ 1 , and may shift a phase of a carrier signal of the section corresponding to the element of −1 to a phase θ 2 . Here, a difference between the phase θ 1 and the phase θ 2 may be 180 degrees. Also, the transmitter may generate a second signal by multiplying the carrier signal shifted to the phase θ 1 by an absolute value of an amplitude of the section corresponding to the element of 1 and by multiplying the carrier signal shifted to the phase θ 2 by an absolute value of an amplitude of the section corresponding to the element of −1. The transmitter may amplify the second signal by inputting the second signal to an amplifier. As shown in a section 841 of an amplified second signal 840 , a difference between a phase of the section corresponding to the element of 1 and a phase of the section corresponding to the element of −1 may be 180 degrees. Also, an output of the section corresponding to the element of 0 may be zero. The transmitter may transmit the amplified second signal 840 to the noncoherent receiver and the coherent receiver.
[0203] Referring to FIG. 9 , a transmitter may modulate a binary data sequence and may transmit the modulated binary data sequence to a low selectivity noncoherent receiver, a high selectivity noncoherent receiver, or a coherent receiver. When a binary data sequence 910 is input to the transmitter, the transmitter may generate a first signal by mapping, to the binary data sequence 910 , a ternary sequence 920 that is preset to correspond to the binary data sequence 910 and by modulating the ternary sequence 920 . The transmitter may input the first signal to a pulse shaping filter and may adjust a frequency band of the first signal not to be widely distributed. In a pulse shaping filter output signal 930 , an amplitude of a section corresponding to an element of 1 may have a positive value, an amplitude of a section corresponding to an element of −1 may have a negative value, and an amplitude of a section corresponding to an element of 0 may be zero.
[0204] In the pulse shaping filter output signal 930 , the transmitter may shift a frequency of a carrier signal of the section corresponding to the element of 1 to a frequency f 1 , and may shift a frequency of a carrier signal of the section corresponding to the element of −1 to a frequency f 2 . Also, the transmitter may shift, to a phase θ 1 , a phase of the carrier signal shifted to the frequency and may shift, to a phase θ 2 , a phase of the carrier signal shifted to the frequency f 2 . Here, an amplitude of the frequency f 2 may be greater than an amplitude of the frequency f 1 and a difference between the phase θ 1 and the phase θ 2 may be 180 degrees. Also, the transmitter may generate a second signal by multiplying the carrier signal shifted to the frequency f 1 and the phase θ 1 by an absolute value of an amplitude of the section corresponding to the element of 1 and by multiplying the carrier signal shifted to the frequency f 2 and the phase θ 2 by an absolute value of an amplitude of the section corresponding to the element of −1. The transmitter may amplify the second signal by inputting the second signal to an amplifier. In a section 941 of an amplified second signal 940 , a difference between the phase of the section corresponding to the element of 1 and the phase of the section corresponding to the element of −1 may be 180 degrees. Also, an output of the section corresponding to the element of 0 may be zero. The transmitter may transmit the amplified second signal 940 to the low selectivity noncoherent receiver, the high selectivity noncoherent receiver, or the coherent receiver.
[0205] FIGS. 10 through 12 are block diagram illustrating examples of a receiver according to an example embodiment.
[0206] Referring to FIG. 10 , a receiver 1000 may include a filter 1010 , an envelope detector 1020 , and a binary data sequence detector 1030 . According to an example embodiment, the receiver 1000 may indicate a low selectivity noncoherent receiver.
[0207] The receiver 1000 may receive a signal from the transmitter of FIG. 3 . The received signal may be a signal converted from a ternary payload sequence including elements of −1, 0, or 1.
[0208] The filter 1010 may filter the received signal using a frequency f 0 . Here, the frequency f 0 may be a frequency between a frequency f 1 and a frequency f 2 . The frequency f 1 denotes a frequency of a section of the received signal converted from the element of 1 and the frequency f 2 denotes a frequency of a section of the received signal converted from the element of −1, in the ternary payload sequence. For example, the frequency f 0 may be the arithmetic mean between the frequency f 1 and the frequency f 2 . For example, an amplitude of the frequency f 2 may be greater than an amplitude of the frequency f 1 . The low selectivity noncoherent receiver may not accurately distinguish the frequency f 1 and the frequency f 2 . Accordingly, the filter 1010 may filter the received signal using the frequency f 0 corresponding to the frequency f 0 between the frequency f 1 and frequency f 2 , and may receive the received signal in a wide bandwidth in order to cover all of the frequency f 1 and the frequency f 2 .
[0209] The envelope detector 1020 may detect an amplitude value of an envelope of the filtered received signal. In a section in which an amplitude of the received signal is not zero between the frequency f 1 and the frequency f 2 , the envelope detector 1020 may detect an envelope of which an amplitude is not zero in the corresponding section. In a section in which an amplitude of the received signal is zero between the frequency f 1 and the frequency f 2 , the envelope detector 1020 may detect a signal of which an amplitude is zero in the corresponding section and that contains only noise. Accordingly, if a signal to noise ratio (SNR) value is greater than or equal to a preset value, the frequency f 1 and the frequency f 2 may not be distinguished in an envelope. Thus, the receiver 1000 may not distinguish the element of 1 and the element of −1 of the ternary payload sequence.
[0210] The binary data sequence detector 1030 may detect a binary data sequence corresponding to the ternary payload sequence based on a correlation between the detected amplitude value of the envelope and desired binary sequences. The binary data sequence detector 1030 may include a correlator 1031 and a data decoder 1032 .
[0211] The correlator 1031 may calculate the correlation between the detected amplitude value and desired binary sequences. For example, the correlator 1031 may calculate a correlation between an amplitude value of each section of the envelope detected at the envelope detector 1020 and desired binary sequences.
[0212] The binary data sequence detector 1030 may detect, as the binary data sequence, a bit sequence corresponding to a binary sequence having a highest correlation with the detected amplitude value of the envelope among the binary sequences.
[0213] According to an example embodiment, the binary data sequence detector 1030 may include information regarding Table 6 or Table 7. The binary data sequence detector 1030 may extract desired binary sequences by converting an element of −1 to an absolute value in the ternary sequences of Table 6 or Table 7. The binary data sequence detector 1030 may calculate a correlation between the binary sequences and the detected amplitude value of the envelope, may search for a bit sequence corresponding to the binary sequence having the highest correlation from Table 6 or Table 7, and may detect the retrieved bit sequence as the binary data sequence.
[0214] For example, the correlator 1031 may calculate a correlation between desired binary sequences [0 0 0 1 1 0 1 1], [1 0 0 0 1 1 0 1], [1 1 0 0 0 1 1 0], and [0 0 1 1 0 1 1 0] and an amplitude value of each section of an envelope. In this example, if the binary sequence [1 0 0 0 1 1 0 1] has a highest correlation among the binary sequences, the binary data sequence detector 1030 may extract a bit sequence, for example, [1 0 0], corresponding to the binary sequence [1 0 0 0 1 1 0 1] as a binary data sequence.
[0215] The data decoder 1032 may decode the binary data sequence.
[0216] Referring to FIG. 11 , a receiver 1100 may include an entire envelope detector 1110 and a binary data sequence detector 1120 . According to an example embodiment, the receiver 1100 may indicate a high selectivity noncoherent receiver.
[0217] The receiver 1100 may receive a signal from the transmitter described with reference to FIGS. 3 and 5 . The received signal may be a signal converted from a ternary payload sequence including elements of −1, 0, or 1. The entire envelope detector 1110 may detect an amplitude value of an envelope of the received signal.
[0218] The entire envelope detector 1110 may include a first filter 1111 , a first envelope detector 1112 , a second filter 1113 , a second envelope detector 1114 , and a calculator 1115 .
[0219] The first filter 1111 may filter the received signal using a frequency f 1 , and the second filter 1112 may filter the received signal using a frequency f 2 . Here, the frequency f 1 may denote a frequency of a section of the received signal in which the element of 1 in the ternary payload sequence is converted, and the frequency f 2 may denote a frequency of a section of the received signal in which the element of −1 in the ternary payload sequence is converted. For example, an amplitude of the frequency f 2 may be greater than an amplitude of the frequency f 1 .
[0220] The first envelope detector 1112 may detect a first envelope indicating an envelope of the received signal filtered based on the frequency f 1 . In a section in which an amplitude of the received signal is not zero at the frequency f 1 , the first envelope detector 1112 may detect an envelope of which an amplitude is not zero in the corresponding section. In a section in which the amplitude of the received signal is zero at the frequency f 1 , the first envelope detector 1112 may detect a signal of which an amplitude is zero in the corresponding section and that contains only noise. Also, in a section in which the amplitude of the received signal is not zero at the frequency f 2 , the first envelope detector 1112 may detect a signal of which an amplitude is zero in the corresponding section and that contains only noise.
[0221] The second envelope detector 1114 may detect a second envelope indicating an envelope of the received signal filtered based on the frequency In a section in which an amplitude of the received signal is not zero at the frequency f 2 , the second envelope detector 1114 may detect an envelope of which an amplitude is not zero in the corresponding section. In a section in which the amplitude of the received signal is zero at the frequency f 2 , the second envelope detector 1114 may detect a signal of which an amplitude is zero in the corresponding section and that contains only noise. Also, in a section in which the amplitude of the received signal is not zero at the frequency f 1 , the second envelope detector 1114 may detect a signal of which an amplitude is zero in the corresponding section and that contains only noise.
[0222] The calculator 1115 may deduct an envelope output from the second envelope detector 1114 from an envelope output from the first envelope detector 1112 . Accordingly, in the section in which the amplitude of the received signal is not zero at the frequency f 1 , the calculator 1115 may output an envelope having a positive amplitude value in the corresponding section. In the section in which the amplitude of the received signal is not zero at the frequency f 2 , the calculator 1115 may output an envelope having a negative amplitude value in the corresponding section. Also, in the section in which the amplitude of the received signal is zero at the frequency f 1 and the frequency f 2 , the calculator 1115 may output an envelope having zero amplitude value in the corresponding section.
[0223] The binary data sequence detector 1120 may detect the binary data sequence corresponding to the ternary payload sequence based on the correlation between the desired ternary sequences and the amplitude value of the envelope detected at the entire envelope detector 1110 . The binary data sequence detector 1120 may include a correlator 1121 and a data decoder 1122 .
[0224] The correlator 1121 may calculate a correlation between the amplitude value of the envelope and each of the ternary sequences. For example, the correlator 1121 may calculate a correlation between an amplitude value of each section of a third envelope and each of the ternary sequences.
[0225] The binary data sequence detector 1120 may detect, as the binary data sequence, a bit sequence corresponding to a ternary sequence having a highest correlation with the detected amplitude value of the envelope among the ternary sequences.
[0226] According to an example embodiment, the binary data sequence detector 1120 may include information regarding Table 6 or Table 7. The binary data sequence detector 1120 may calculate a correlation between the ternary sequences of Table 6 or Table 7 and the detected amplitude value of the envelope, may search for a bit sequence corresponding to the ternary sequence having the highest correlation from Table 6 or Table 7, and may detect the retrieved bit sequence as the binary data sequence.
[0227] For example, the correlator 1121 may calculate a correlation between desired binary sequences [0 0 0 1 −1 0 1 1], [1 0 0 0 1 −1 0 1], [1 1 0 0 0 1 −1 0], and [0 0 1 −1 0 1 1 0] and an amplitude value of each section of an envelope. In this example, if the binary sequence [1 0 0 0 1 −1 0 1] has a highest correlation among the binary sequences, the binary data sequence detector 1120 may extract a bit sequence, for example, [1 0 0], corresponding to the binary sequence [1 0 0 0 1 −1 0 1] as a binary data sequence.
[0228] The data decoder 1122 may decode the binary data sequence.
[0229] Referring to FIG. 12 , the receiver 1200 may include a correlation detector 1210 and a binary data sequence detector 1220 . According to an example embodiment, the receiver 1200 may indicate a coherent receiver.
[0230] The receiver 1200 may receive a signal from the transmitter described with reference to FIGS. 3 and 6 . The received signal may be a signal converted from a ternary payload sequence including elements of −1, 0, or 1. The correlation detector 1210 may detect a correlation between the received signal and a carrier signal. The correlation detector 1210 may include a radio frequency (RF)/analog processor 1211 and a first correlator 1211
[0231] The RF/analog processor 1211 may convert the received signal, received via an antenna, to be processed at the first correlator 1212 . The first correlator 1212 may detect a correlation between a reference signal and the received signal. For example, a phase detector may calculate a correlation between a sinusoidal carrier signal and the received signal.
[0232] The binary data sequence detector 1220 may detect a binary data sequence of the received signal based on a correlation between a result value of the correlation and desired ternary sequences. The binary data sequence detector 1220 may include a second correlator 1221 and a data decoder 1222 .
[0233] The second correlator 1221 may calculate a correlation between a result value of the correlation calculated at the first correlator 1212 and the ternary sequences. The binary data sequence detector 1220 may detect, as the binary data sequence, a bit sequence corresponding to a ternary sequence having a highest correlation with the result value of the correlation calculated at the first correlator 1212 among the ternary sequences.
[0234] According to an example embodiment, the binary data sequence detector 1220 may include information regarding Table 6 or Table 7. The binary data sequence detector 1220 may calculate a correlation between the ternary sequences of Table 6 or Table 7 and the amplitude value of the envelope, may search for a bit sequence corresponding to the ternary sequence having the highest correlation from Table 6 or Table 7, and may detect the retrieved bit sequence as the binary data sequence.
[0235] The data decoder 1222 may decode the binary data sequence.
[0236] FIGS. 13 through 15 illustrate examples of detecting a binary data sequence according to an example embodiment.
[0237] A graph of FIG. 13 shows a spectrum 1311 of a transmission signal transmitted from a transmitter and a filter frequency response 1312 at a low selectivity noncoherent receiver. In the graph, a horizontal axis denotes a frequency and a vertical axis denotes a spectrum power.
[0238] A frequency f 1 of the spectrum 1311 may denote a frequency of a section of the transmission signal converted from an element of 1 in a ternary payload sequence, and a frequency f 2 may denote a frequency of a section of the transmission signal converted from an element of −1 in the ternary payload sequence. According to an example embodiment, a frequency f 0 may be the arithmetic mean of the frequency f 1 and the frequency f 2 .
[0239] The low selectivity noncoherent receiver may not accurately distinguish the frequency f 1 and the frequency f 2 from each other. Accordingly, to cover all of the frequency f 1 and the frequency f 2 , the low selectivity noncoherent receiver may filter the received signal based on the frequency f 0 that is an intermediate frequency between the frequency f 1 and the frequency f 2 using the filter frequency response 1312 .
[0240] The low selectivity noncoherent receiver may detect an envelope of the filtered received signal. The low selectivity noncoherent receiver may detect a binary data sequence corresponding to the ternary payload sequence based on a correlation between an amplitude value of the envelope and desired binary sequences.
[0241] A graph of FIG. 14 shows a spectrum 1411 of a transmission signal transmitted from a transmitter and filter frequency responses 1412 and 1413 at a high selectivity noncoherent receiver. In the graph, a horizontal axis denotes a frequency and a vertical axis denotes a spectrum power.
[0242] The transmitter may transmit a transmission signal having the spectrum 1411 to the high selectivity noncoherent receiver.
[0243] A frequency f 1 of the spectrum 1411 may denote a frequency of a section of the transmission signal converted from an element of 1 in a ternary payload sequence, and a frequency f 2 may denote a frequency of a section of the transmission signal converted from an element of −1 in the ternary payload sequence. According to an example embodiment, a frequency f 0 may be the arithmetic mean of the frequency f 1 and the frequency f 2 .
[0244] The high selectivity noncoherent receiver may filter the received signal using a first filter in which the frequency f 1 is set as a center frequency and a second filter in which the frequency f 2 is set as a center frequency. The first filter may filter the received signal based on the frequency f 1 using the filter frequency response 1412 , and the second filter may filter the received signal based on the frequency f 2 using the filter frequency response 1413 .
[0245] The high selectivity noncoherent receiver may detect an envelope of the received signal filtered based on the frequency f 1 and an envelope of the received signal filtered based on the frequency f 2 , and may deduct the envelope of the received signal filtered based on the frequency f 2 from the envelope of the received signal filtered based on the frequency f 1 . Accordingly, a section in which the amplitude of the received signal is not zero at the frequency f 1 may appear as an envelope having a positive amplitude value. A section in which the amplitude of the received signal is not zero at the frequency f 2 may appear as an envelope having a negative amplitude value. A section in which the amplitude of the received signal is zero at the frequency f 1 and the frequency f 2 may appear as an amplitude having zero amplitude value.
[0246] The high selectivity noncoherent receiver may detect a binary data sequence corresponding to the ternary payload sequence based on the correlation between the amplitude value of the amplitude and the desired ternary sequences.
[0247] Referring to FIG. 15 , coordinates may indicate a phase ̂ 1511 of a section corresponding to an element of 1 and a phase θ 2 1512 of a section corresponding to an element of −1 in a ternary payload sequence of a received signal received at a coherent receiver. Here, the phase ̂ 1511 may indicate zero degrees and the phase θ 2 1512 my indicate 180 degrees.
[0248] The coherent receiver may detect a correlation between a sinusoidal carrier signal and the received signal.
[0249] Also, the coherent receiver may detect a binary data sequence corresponding to the ternary payload sequence based on a correlation between a correlation result value and a desired ternary sequence.
[0250] FIG. 16 is a bloc diagram illustrating a transmitter according to another example embodiment.
[0251] Referring to FIG. 16 , a transmitter 1600 may include a ternary sequence mapper 1610 and a converter 1620 . According to an example embodiment, the transmitter 1600 may include the first signal converter 310 of FIG. 3 .
[0252] The ternary sequence mapper 1610 may generate a ternary payload sequence including elements of −1, 0, or 1 by mapping a pre-designed ternary sequence to a binary data sequence.
[0253] According to an example embodiment, the ternary sequence mapper 1610 may extract, from Table 8, a ternary sequence corresponding to the binary data sequence as the pre-designed ternary sequence. In Table 8, C 0 denotes a sequence of [0 0 0 1 −1 0 1 1] and C m denotes a sequence acquired by cyclic shifting C 0 to right by m. Here, m denotes an integer between 1 and 7.
[0000]
TABLE 8
Binary data sequence
Data symbol
Ternary sequence
3-tuple
m ∈
c m ∈
000
0
c 0
100
1
c 1
110
2
c 2
010
3
c 3
011
4
c 4
111
5
c 5
101
6
c 6
001
7
c 7
[0254] According to another example embodiment, the ternary sequence mapper 1610 may extract, from Table 9, the ternary sequence corresponding to the binary data sequence as the pre-designed ternary sequence. In Table 9, C 0 denotes a sequence of [−1 0 0 1 0 1 −1 0 −1 −1 1 −1 0 1 0 1 0 0 0 1 0 0 1 1 −1 0 0 0 0 0 1 1] and 0, denotes a sequence acquired by cyclic shifting C 0 to right by m. Here, m denotes an integer between 1 and 31.
[0000]
TABLE 9
Binary data sequence
Data symbol
Ternary sequence
5-tuple
m ∈
c m ∈
00000
0
c 0
10000
1
c 1
11000
2
c 2
01000
3
c 3
01100
4
c 4
11100
5
c 5
10100
6
c 6
00100
7
c 7
00110
8
c 8
10110
9
c 9
11110
10
c 10
01110
11
c 11
01010
12
c 12
11010
13
c 13
10010
14
c 14
00010
15
c 15
00011
16
c 16
10011
17
c 17
11011
18
c 18
01011
19
c 19
01111
20
c 20
11111
21
c 21
10111
22
c 22
00111
23
c 23
00101
24
c 24
10101
25
c 25
11101
26
c 26
01101
27
c 27
01001
28
c 28
11001
29
c 29
10001
30
c 30
00001
31
c 31
[0255] The converter 1620 may convert the ternary payload sequence to a signal.
[0256] The description made above with reference to FIGS. 1 through 15 may be applicable to the transmitter of FIG. 16 , and a further description related thereto will be omitted.
[0257] FIG. 17 is a block diagram illustrating a receiver according to another example embodiment.
[0258] Referring to FIG. 17 , a receiver 1700 may include a signal receiver 1710 and a detector 1720 . According to an example embodiment, the receiver 1700 may refer to the receiver 1200 , 1300 , 1400 described with reference to FIGS. 10 through 12 .
[0259] The signal receiver 1710 may receive a signal demodulated from a ternary payload sequence generated by mapping a pre-designed ternary sequence to a binary data sequence and including elements of −1, 0, or 1.
[0260] The detector 1720 may detect the pre-designed ternary sequence and binary data sequence.
[0261] According to an example embodiment, the detector 1720 may detect the pre-designed ternary sequence and the binary data sequence using Table 10. In Table 10, C 0 denotes a sequence of [0 0 0 1 −1 0 1 1] and 0, denotes a sequence acquired by cyclic shifting C 0 to right by m. Here, m denotes an integer between 1 and 7.
[0000]
TABLE 10
Binary data sequence
Data symbol
Ternary sequence
3-tuple
m ∈
c m ∈
000
0
c 0
100
1
c 1
110
2
c 2
010
3
c 3
011
4
c 4
111
5
c 5
101
6
c 6
001
7
c 7
[0262] According to another example embodiment, the detector 1720 may detect the pre-designed ternary sequence and the binary data sequence using Table 11. In Table 11, C 0 denotes a sequence of [−1 0 0 1 0 1 −1 0 −1 −1 1 −1 0 1 0 1 0 0 0 1 0 0 1 1 −1 0 0 0 0 0 1 1] and 0, denotes a sequence acquired by cyclic shifting C 0 to right by m. Here, no denotes an integer between 1 and 31.
[0000]
TABLE 11
Binary data sequence
Data symbol
Ternary sequence
5-tuple
m ∈
c m ∈
00000
0
c 0
10000
1
c 1
11000
2
c 2
01000
3
c 3
01100
4
c 4
11100
5
c 5
10100
6
c 6
00100
7
c 7
00110
8
c 8
10110
9
c 9
11110
10
c 10
01110
11
c 11
01010
12
c 12
11010
13
c 13
10010
14
c 14
00010
15
c 15
00011
16
c 16
10011
17
c 17
11011
18
c 18
01011
19
c 19
01111
20
c 20
11111
21
c 21
10111
22
c 22
00111
23
c 23
00101
24
c 24
10101
25
c 25
11101
26
c 26
01101
27
c 27
01001
28
c 28
11001
29
c 29
10001
30
c 30
00001
31
c 31
[0263] The description made above with reference to FIGS. 1 through 15 may be applicable to the receiver of FIG. 17 , and a further description related thereto will be omitted.
[0264] FIG. 18 is a flowchart illustrating a transmission method according to an example embodiment.
[0265] Referring to FIG. 18 , in operation 1810 , a transmitter my generate a ternary payload sequence by mapping a pre-designed sequence to a binary data sequence.
[0266] In operation 1820 , the transmitter may convert the ternary payload sequence to a first signal.
[0267] The description made above with reference to FIGS. 1 through 15 may be applicable to the transmission method of FIG. 18 , and a further description related thereto will be omitted.
[0268] FIG. 19 is a flowchart illustrating a transmission method according to another example embodiment.
[0269] Referring to FIG. 19 , in operation 1910 , a transmitter may convert a ternary payload sequence including elements of −1, 0, or 1 to a first signal.
[0270] In operation 1920 , the transmitter may convert the first signal to a second signal by applying a different conversion scheme to each section of the first signal based on an element.
[0271] The description made above with reference to FIGS. 1 through 15 may be applicable to the transmission method of FIG. 19 , and a further description related thereto will be omitted.
[0272] FIGS. 20 through 23 are flowcharts illustrating examples of a reception method according to an example embodiment.
[0273] Referring to FIG. 20 , in operation 2010 , a receiver may detect an amplitude value of an envelope of a received signal converted from a ternary payload sequence including elements of −1, 0, or 1.
[0274] In operation 2020 , the receiver may detect a binary data sequence corresponding to the ternary payload sequence based on a correlation between the detected amplitude value of the envelope and desired binary sequences.
[0275] The description made above with reference to FIGS. 1 through 15 may be applicable to the reception method of FIG. 20 , and a further description related thereto will be omitted.
[0276] Referring to FIG. 21 , in operation 2110 , a receiver may detect an amplitude value of an envelope of a received signal converted from a ternary payload sequence including elements of −1, 0, or 1.
[0277] In operation 2120 , the receiver may detect a binary data sequence corresponding to the ternary payload sequence based on a correlation between the detected amplitude value of the envelope and desired ternary sequences.
[0278] The description made above with reference to FIGS. 1 through 15 may be applicable to the reception method of FIG. 21 , and a further description related thereto will be omitted.
[0279] Referring to FIG. 22 , in operation 2210 , a receiver may detect a correlation between a reference signal and a received signal converted from a ternary payload sequence including elements of −1, 0, or 1.
[0280] In operation 2220 , the receiver may detect a binary data sequence corresponding to the ternary payload sequence based on a result value of the correlation and desired ternary sequences.
[0281] The description made above with reference to FIGS. 1 through 15 may be applicable to the reception method of FIG. 22 , and a further description related thereto will be omitted.
[0282] Referring to FIG. 23 , in operation 2310 , a receiver may receive a signal modulated from a ternary payload sequence generated by mapping a pre-designed ternary sequence to a binary data sequence and including elements of −1, 0, or 1.
[0283] In operation 2320 , the receiver may detect the pre-designed ternary sequence and the binary data sequence. Here, the receiver may detect the pre-designed ternary sequence and the binary data sequence using Table 10 and Table 11.
[0284] The apparatuses described herein may be implemented using hardware components, software components, and/or combination of the hardware components and the software components. For example, the apparatuses and the components may be configured using at least one universal computer or special purpose computer, for example, a processor, a controller and an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA), a programmable logic unit (PLU), a microprocessor or any other device capable of responding to and executing instructions in a defined manner. The processing device may run an operating system (OS) and one or more software applications that run on the OS. The processing device also may access, store, manipulate, process, and create data in response to execution of the software. For purpose of simplicity, the description of a processing device is used as singular; however, one skilled in the art will appreciated that a processing device may include multiple processing elements and multiple types of processing elements. For example, a processing device may include multiple processors or a processor and a controller. In addition, different processing configurations are possible, such as parallel processors.
[0285] The software may include a computer program, a piece of code, an instruction, or some combination thereof, to independently or collectively instruct and/or configure the processing device to operate as desired, thereby transforming the processing device into a special purpose processor. Software and/or data may be embodied permanently or temporarily in any type of machine, component, physical or virtual equipment, computer storage medium or device, or in a propagated signal wave capable of providing instructions or data to or being interpreted by the processing device. The software also may be distributed over network coupled computer systems so that the software is stored and executed in a distributed fashion. The software and data may be stored by one or more non-transitory computer readable recording mediums.
[0286] The methods according to the above-described example embodiments may be recorded in non-transitory computer-readable media including program instructions to implement various operations of the above-described example embodiments. The media may also include, alone or in combination with the program instructions, data files, data structures, and the like. The program instructions recorded on the media may be those specially designed and constructed for the purposes of examples, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of non-transitory computer-readable media include magnetic media such as hard disks, floppy disks, and magnetic tape; optical media such as CD-ROM discs, DVDs, and/or Blue-ray discs; magneto-optical media such as optical discs; and hardware devices that are specially configured to store and perform program instructions, such as read-only memory (ROM), random access memory (RAM), flash memory (e.g., USB flash drives, memory cards, memory sticks, etc.), and the like. Examples of program instructions include both machine code, such as produced by a compiler, and files containing higher level code that may be executed by the computer using an interpreter. The above-described devices may be configured to act as one or more software modules in order to perform the operations of the above-described example embodiments, or vice versa.
[0287] Although example embodiments are described with reference to some example embodiments and drawings, it will be apparent to one of ordinary skill in the art that various modifications and alterations may be made from the description. For example, suitable results may be achieved if the described techniques are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined in a different manner, and/or replaced or supplemented by other components or their equivalents.
[0288] Therefore, the scope of the example embodiments is defined not by the detailed description, but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are to be construed as being included in the example embodiments.
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The present invention relates to a method and a device for transmitting a pay load sequence, and provides in one embodiment a transmitter comprising a first signal converter for converting a ternary payload sequence composed of elements −1, 0, or 1 into a first signal, wherein the first signal converter comprises: a ternary sequence mapper for generating the ternary payload sequence by mapping a pre-designed sequence into a binary data sequence; and a converter for converting the ternary payload sequence into the first signal.
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BACKGROUND AND SUMMARY OF THE INVENTION
This invention pertains to a device for the recovery of waste heat from household laundry driers. The device is also useful as a stand for elevating the entry to the drier to a level where the laundered goods can be placed in the drier without stooping or bending over, thus resulting in easier loading of the drier.
Most household laundry driers are loaded from the front and therefore, if the drier is set directly on the floor, loading the machine requires bending over. For most people such bending is inconvenient, and for some it may be painful. The device of this invention relieves that need to stoop or bend.
Heat either from the burning of gas or from electric power is ordinarily used to assist in the drying. Not all of this heat is used in the process, and the excess is commonly wasted by sending the exhaust air to the exterior of the building in which the drier is housed. In most times, that seems reasonable. However, when the ambient air is cold the wasted heat is completely wasted while other sources are relied on to heat the room.
The device of this invention also provides for convenient use of the heat which might otherwise be wasted. This is accomplished readily by opening or closing a single vent which routes the heated air either into or out of the room.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a perspective view of the stand device from the front showing its auxiliary drier open;
FIG. 2 is a perspective view from the rear of the stand.
FIG. 3 is a detailed elevational view of a hinge on the second outlet.
DESCRIPTION
Briefly the invention comprises a stand on which a household laundry drier may be set. The stand includes provisions for returning heated air from the drier either to the outside air or to the room in which the drier is set, whichever is desired. A simple and convenient system is used to provide for the selection.
More specifically and referring to the drawings, the invention is embodied in a single cabinet-like stand 10. This stand should be approximately 10 to 15 inches high so that the entrance to the drier will be at a level convenient for the user to load without stooping. This feature will be particularly useful with the top-loading household washing machines where the unloading of the washer will be done at about the same level as the loading of the drier.
With a stand of about 10 or more inches in height, it will be possible to use two compartments in the stand divided by a divider 9. The upper compartment 11 is the compartment which handles the waste air for the drier (not shown) while the lower compartment 12 may be used for storage and be built to provide for a drawer 13 or the like.
The upper compartment 11 is built with an inlet for the exhaust hose 15 from the drier. This hose is connected through a lint trap 16 (FIG. 2) and thence is opened into the upper compartment 11.
The compartment 11 is simply an open chamber, but it has two outlets. The first outlet 18 may be at the front of the stand or may at any wall having a free opening into the room in which the drier is set. Because of the possibility of a variety of settings, the front wall 20 would be the one that would be most assured of being free. Therefore, the front wall is the preferred location for the inside vent outlet 18. This outlet includes a control 21 adapted to open or close the vent to allow the air in the upper compartment to escape readily into the room or to be substantially prevented from entry into the room.
The second outlet 22 is built into the side of the stand which will be placed against an exterior wall of the laundry room. If necessary, a duct may lead from the outlet to and through that wall. For purposes of illustration and ease of explanation, no ducting is shown. Such ducting is well within the abilities of one skilled in the art of installation of larger appliances such as driers.
The outlet itself comprises a flap 23 which may be made of wood or other material such as plastic. Hinges 24 at the top of the flap 23 allow it to close by gravitational force alone. If desired, light springs 26 in the hinges might be desirable to hold the flap 23 in its normally closed position.
In operation, the stand 10 is placed so that the second outlet 22 is adjacent to an exterior wall. If necessary, proper venting of that outlet through that wall should be provided. The drier is placed on the stand, and the exhaust hose 15 is run from the drier to the lint filter 16 so that heated air for the drier will exhaust into the chamber 11.
The above description will cover most models of drier. In some drier devices, the vent exits directly from the bottom of the drier. In those models, a lint trap similar to the filter 16 may be inserted between the bottom of the drier and a matching opening in the top of the upper chamber 11 so that the discharge from the drier bottom exhausts through the filter directly into the upper chamber.
So long as the drier is not in use, the flap 23 will be closed by the force of gravity and the force of the opening 26. This provides entry into the chamber 11 of air at an undesirable temperature (too hot or too cold) from outside and also guards against the entrance of insects, mice, or the like.
When the device is in use, air will be impelled by a fan in the drier throughout the hose 15 into the chamber 11. If it is desired to use this warmed air to heat the room, the grill on the first outlet 18 can be opened, and the air from the drier will simply be exhausted from the chamber 11 into the laundry room. On the other hand, if such heating is not desired in the room, the grill 18 may be closed. Pressure in the chamber 17 will then build up until it overcomes the weight of the flap 23 and any springs 26 which might be used. The flap 23 will then open the second outlet 22 and the warmed air from the drier will be exhausted outside. Thus, by use of the stand, a convenient diversion device is available to raise the drier to a convenient level and to make possible alternate uses of the heated air from the drier.
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A heat salvaging device for a household laundry drier. The device may serve both as a stand for the drier and a device for salvaging waste heat from the drying process. The heat salvaging operation is controlled by controlling a single vent in the stand.
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FIELD OF INVENTION
[0001] The present invention relates to CNC cut panels or parts used in the building industry to provide designed parts for the railing industry, ginger-bread attachments for the decorative “VICTORIAN LOOK”, adjustable valances for archways and the like.
BACKGROUND OF THE INVENTION
[0002] Currently in building railing for staircases using spindles, pickets, decorative rods and the like, also non-rectangular balusters and shapes because generally and in the situation of spiral staircases the angle or pitch is not a standard or fixed angle. Prior installations of decorative metal panelling needed the services of a blacksmith for every elevating inch of a staircase banister or panel a custom bent and forged shape is fabricated to fit the pitch of the staircase stringer and top rail assembly which is generally built and assembled first so that the shape is determined.
SUMMARY OF THE INVENTION
[0003] According to one aspect of the invention there is provided a decorative panel system comprises:
[0004] a main body having a consistent resistance to bending;
[0005] means for mounting the panel to a suitable support structure;
[0006] at least one distortion section on the main body having less resistance to bending in relation to the main body such that the distortion section bends at a localised point.
[0007] Preferably the distortion section has a plurality of radius points which are arranged to compress or expand to accommodate mounting points of the panel.
[0008] One embodiment of the invention will now be described in conjunction with the accompanying drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 is a front view of the present invention.
[0010] [0010]FIG. 2 is a partial front view of the present invention.
[0011] [0011]FIG. 3 is a front view of a second embodiment of the present invention.
[0012] [0012]FIG. 4 is a front view of a part of the present invention.
[0013] In the drawings like characters of reference indicate corresponding parts in the different figures.
DETAILED DESCRIPTION
[0014] As illustrated in FIGS. 1 and 2, a railing assembly 1 for a staircase 3 or the like has a top rail 5 and a bottom rail 7 . The top and bottom rails are supported at each respective end by a end mount 9 . The end mount is arranged to be coupled to a supporting surface such as a wall or the like. The end mounts have a pivot 11 which is connected to the rail such that the angle from the wall to wall can be varied slightly. The rails are arranged to be parallel links by placing a plurality of spaced posts 13 separating the top and bottom rail. The bottom rail can be replaced by using the stair stringer of the existing staircase. Between each post connected at a top end 15 and a bottom end 17 is a decorative panel 19 or baluster. The decorative panel is cut from a single section of metal by a laser. Each top end and bottom end of the panel has a pair of legs 21 which are arranged to be mounted to a bottom side 23 and top side 25 of each respective top and bottom rail between two respective posts. The legs have rubber grommets 27 which are inserted into an insert portion 29 on the rails. The grommets support the panel between the rails. The panels are vertical on the rails such that a respective leg on the panel is higher on the rail that the next.
[0015] Each panel, as illustrated, has two distortion sections 31 adjacent the top end and bottom end of the panel. The distortion sections has less resistance to bending in relation to the rest of the panel such that the distortion section bends at a localised point. The distortion section has a plurality of radius points 33 A, 33 B and 33 C which are arranged to compress or expand to accommodate the angle of the rails. The distortion section allows a builder to adjust the panel such that the panels can be delivered to the site and fitted to the stairs.
[0016] In construction of the rail assembly, the rails are positioned on the with the panels and posts positioned in the respectable positions. The panels will compress and expand at the distortion section to fit to the desired angle of the stair without distorting the pattern on the panel. In one example of mounting the rail assembly, in a method more suitable for the most complicated installation being the spiral staircase installation where the staircase stringer angle is consistently changing. An installer first mounts the base of the panel or baluster to the stair stringer. The next step is to bend or adjust the panel or baluster at the distortion portion so that an imaginary centre line of the body of the panel or baluster is vertical. Keeping the body or the panel vertical adjust or bend the top portion of the panel to fit the top rail angle or pitch and install the top rail.
[0017] In a second example of installation of the rail assembly the installer can first measure or calculate the angle or the incline and simple pre bend or shape all of the panels to match the installation angle.
[0018] In a third example of installation, in the case of the parallel link, assemble the desired number of panels and pickets as an assembly. When the four pivoting brackets are attached to create a parallel link and the assembly is mounted to a wall or post. The entire assembly can be adjusted as a unit to fit the staircase angle or pitch. All of the pivot points will adjust in unison to each other automatically or by design.
[0019] As illustrated in FIG. 3, a second embodiment of the present invention is arranged to be used in at peaks of external walls of a building such as a house. There are general standards in the building industry in regards to the angle or pitch that a roof is built to for example 12:12 pitch means 12′ vertical and 12′ horizontal which would be a 90 degree angle (4:12), (6:12), (8:12), (10:12) are also common angles. However because of uncertain circumstance these angles may change slightly so that an adjustable angle (ginger-bread) attachment 41 for each general pitch would be most ideal and useful to the installer, builder, end-user. One would simply select the closest to fit angle part (attachment) to fit the situation and then first bolt, screw, attach one side or the other so that the straight edge would line up with the roof angle then simply adjust by bending the un-attached side of the attachment in the appropriate direction to fit the other or opposite roof line or angle. Install the remainder of the screws and the insulation is complete.
[0020] The gingerbread attachment is generally, as illustrated, triangular in shape such that a top peak 45 is arranged to fit in the top portion of an exterior peak of a house or the like. The gingerbread attachment has a distortion portion 47 between two end corners 49 which is arranged to be distorted in order to adequately fit the gingerbread attachment as desired such that the top peak is shaped outwards or inwards.
[0021] These types of decretive attachments have traditionally been hand made of wood or casted which of coarse will affect the life span and the practical availability in size and selection of the product.
[0022] With the use of CNC. Computer controlled laser or water-jet cutting it is feasible that thousands of very intricate parts can be produced in many different sizes and shapes in mass production volumes.
[0023] Since various modifications can be made in my invention as herein above described, and many apparently widely different embodiments of same made within the spirit and scope of the claims without department from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense.
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A decorative panel system comprising a main body having a consistent resistance to bending and means for mounting the panel to a suitable support structure. Including at least one distortion section on the main body having less resistance to bending in relation to the main body such that the distortion section bends at a localised point. The distortion section has a plurality of radius points which are arranged to compress or expand to accommodate mounting points of the panel.
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CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part patent application of our U.S. patent application Ser. No. 08/120,405, filed Sep. 13, 1993, now U.S. Pat. No. 5,331,699, entitled "INFANT SLEEP SUPPORT".
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to devices for restraining a sleeping infant to keep the infant on its side and to prevent the infant from falling off its sleep platform.
2. General Background
In the Tuesday, Aug. 10, 1993, issue of the New York Times, page B6, an article on studies concerning Sudden Infant Death Syndrome, reports mounting evidence indicating that babies who sleep face down are at a greater risk than those who sleep on their backs and sides. One study reported in the article, conducted by the Menzies Center for Population Health Research at the University of Tasmania, supports an earlier study published by the American Pediatric Association in May of 1992 in finding that infants who slept on their sides were at less of a risk of dying from Sudden Infant Death Syndrome than infants who slept on their stomachs. The article alludes to the concerns of some pediatricians, however, about infants sleeping on their backs and risking inhalation of stomach fluids. Earlier studies and insights into these phenomena have resulted in a number of devices for controlling sleeping posture, some of which are particularly adapted to overcome risks of Sudden Infant Death Syndrome.
3. Prior Art
U.S. Pat. No. 5,189,748 issued to Garrison et al. on Mar. 2, 1993, discloses a device to keep an infant on its side while sleeping and thus avoid Sudden Infant Death Syndrome. The infant side support has a back support and abdominal support attached to a mat on which the infant is laid on its side between the two supports. The infant is kept in a stationary position as a result of the structure, to avoid turning on its back or its stomach. The device has one apparent shortcoming, in that it does not keep an infant who is smaller than the distance between the back support and the abdominal support from twisting onto its back or into a face down position.
U.S. Pat. No. 5,193,238, issued to Clute on Mar. 16, 1993, discloses a support pillow with two detachable main sections, each having an elongated right triangle wedge shaped from a resilient foam member covered with fabric. The two detachable main sections may be spaced apart from one another, with a VELCRO™ brand fastening means attached to each section so that they are in a set spaced relationship. The infant is placed between the two wedges. A strap may be attached across the top of the wedge shaped pillows to stationarily support the pillows. This device also has an apparent shortcoming in that it is particularly confining to the infant, pinning its arms between the two wedges while the infant is sleeping.
Other devices have been disclosed which might be used for the purpose of supporting an infant on its side, or at least avoiding its sleeping in a prone position, though not particularly designed for that purpose. U.S. Pat. No. 3,034,802 issued to Lund on May 15, 1962, discloses an infant holder for restraining the movement of a small child, although it was not designed for keeping the child on its side or back during sleeping. The Lund device was designed for restraining a child during certain operative procedures and medical administrations to avoid injuring the child. It shortcoming it that it is not a comfortable device for the child to sleep in and that it restrains the child to lie on his or her back.
U.S. Pat. No. 4,214,326 issued to Spann on Jul. 29, 1980, discloses an apparatus for positioning and protecting a patient in a bed. The apparatus has protective cushioning for a side frame of the bed. The protective cushioning is substantially cylindrical, except for a fiat surface. The device could be downsized for an infant. It is not, however, adapted to keep the infant from rolling in both directions, as a back device would restrain the infant from rolling on its back but the front device is only to protect the infant from injuring itself on the crib restraining rail.
U.S. Pat. No. 3,924,282 issued to Bond on Dec. 9, 1975, discloses a therapeutic prop-like support for maintaining a sleeping or otherwise reclining person on his or her side. Again, the device is not particularly designed for an infant. Its structure would restrain an infant in the manner of the device disclosed by Clute, if the Bond device were downsized.
U.S. Pat. No. 4,574,412 issued to Smith on Mar. 11, 1986, discloses an L-shaped anchored pillow. The Smith device uses a mat having a VELCRO™ brand strip to which the pillow support may be easily attached to keep it stationary with respect to the mat. This device, too, might be downsized for an infant but would not restrain the infant from rolling on its face if the pillow were situated at the back of the infant.
Besides the particular shortcomings discussed in connection with each of the above presented prior art, all of the above prior art suffers from not providing a combination of a frontal support to prevent the child from rolling onto its stomach, adjustability for different sized infants, portability and washability and a means for keeping the infant or a small child from rolling off its sleep platform, while not unnecessarily confining the infant or child during its sleep. There fore, there is a need for a suitable structured infant sleep support to reduce the occurrence of Sudden Infant Death Syndrome with other advantages conceived of by the inventors of the infant sleep support.
SUMMARY OF THE INVENTION
According to the present invention, an infant sleep support has a planar terry cloth sheet base on which an infant may be placed on its side so that the infant rests on the sheet base. The infant sleep support also has a cylindrical pillow against which the infant may rest its back. The planar sheet base extends from the front of the cylindrical pillow, and a sheet flap extends from the back of the pillow, underneath of the pillow in the direction of the sheet base.
The pillow includes a pillow cover to which the sheet base and the sheet flap are attached, all of which are made of the same material, preferably a soft terry cloth. The pillow cover and pillow are constructed in a shape that is substantially cylindrical as it extends around its axis from the front, which faces the infant, to the back, and there, extends downwardly, as the pillow is generally orientated in uses to a planar back that is tangent to the cylindrical shape. Beneath the sheet base are fasteners that cooperate with complementary fasteners disposed on the top side of the sheet flap, relative to the orientation of the infant sleep support when in use. These fasteners are attached to one another so that the sheet flap fixedly closes an opening to the interior of the pillow cover, enclosing a pillow bolster therein. The pillow bolster, which is placed in the interior of pillow cover to form the pillow, is constructed to be soft, yet supporting. It has an outer surface, preferably of vinyl or some other material impermeable to liquids.
Another embodiment of the invention has a sheet base and sheet flap that can be tucked under a mattress. Yet another embodiment of the infant sleep support has an additional element of a abdominal brace attached to the joinder of the pillow cover and the sheet base. With this latter embodiment, a diaper strap is attached to the cylindrical front surface of the pillow cover. The abdominal brace and the diaper strap both have free ends with fasteners attached thereto. When an infant is placed upon the sheet base and the abdominal brace, the diaper strap is threaded between the legs of the infant and its fastener is attached to one of the fasteners on the abdominal brace. The infant may then be captured by pulling the abdominal brace upwards and around the infant and the other fastener on the abdominal brace may be attached to a fastener on the cylindrical pillow cover to secure the infant in place. The diaper strap secures the infant against wiggling downwardly to threaten strangulation by the abdominal brace.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the infant sleep support with an infant in place.
FIG. 2 is a perspective underside view of the infant sleep support.
FIG. 3 is an exploded underside perspective view of the infant sleep support.
FIG. 4 is a side view of the infant sleep support with a baby in place.
FIG. 5 is a perspective top view of the infant sleep support without a baby, showing another embodiment thereof.
FIG. 6 and FIG. 7 are top perspective views of the embodiment shown in FIG. 5 with a baby in place.
FIG. 8 is a perspective view of one element of the infant sleep support.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1-4, the infant sleep support shown generally at 10 is placed on a mattress or other sleep platform 12 and an infant 14 is placed on the infant sleep support 10. More particularly, the infant is placed on its side so that the infant rests on a planar terry cloth sheet base 16. The infant 14 also rests his or her back against a cylindrical pillow 18, preferably also made of a terry cloth fabric.
As can be seen in FIG. 2, the planar sheet base 16 extends from the front of the cylindrical pillow 18, that is, the portion of the pillow 18 against which the infant 14 (FIG. 1) has his or her back supported. Extending from the back of the pillow is a sheet flap 20, which extends underneath of the pillow in the direction of the sheet base 16.
Referring now to FIG. 3, it can be understood that the pillow 18 comprises a pillow cover 22 to which the sheet base 16 and the sheet flap 20 are attached. The sheet base 16, the sheet flap 20, and the pillow cover 22 are all made of the same material, preferably a soft terry cloth material chosen for its comforting and caressing characteristics. The pillow cover 22 is constructed to provide a substantially cylindrical interior. Actually, the shape of the cover 22 is such that it is substantially cylindrical as it extends around its axis from the front, which faces the infant 14, to the back. There, a generally a planar back 22a is tangent to the cylindrical shape. The planar tangent back 22a extends from its line of tangency to the cylinder shape downwardly to the sheet flap 20. This shape is provided so that the bottom of the pillow may be substantially flat as it rests upon the mattress 12 (FIG. 1), and the base 22b (FIG. 2) of the planar back 22a provides leverage against the force of the infant 14 pushing against the pillow 18 as seen in the figures planar back 22a and planar base 22b are at generally right angles to each other.
Beneath the sheet base 16 are fasteners 24. Fasteners 24 are preferably of the-hook-and-loop complementary fasteners of the type made by VELCRO™ brand. The fasteners beneath the sheet base 16 are either hook or loop. Complementary fasteners 26, either loop or hook, are disposed on the top side of sheet flap 20, relative to the orientation of the infant sleep support when in use, which mate with the fasteners 24 to attach the sheet flap 20 to the sheet base 16. With this attachment, the interior 28 of the pillow cover 22 is fully enclosed.
In the exploded view of FIG. 3, there is seen a pillow bolster 30 which is placed in the interior 28 of pillow cover 22 to form pillow 18. The bolster 30 is shaped as the cover and is constructed to be soft, yet supporting. One such construction might involve a center core 32 which is made of a cylinder of rigid material, such as wood or plastic such as a foam plastic or foam rubber. Surrounding the inner core are foam rubber 34 and/or other cotton or soft padding 36. The outer surface of bolster 30 is preferably vinyl or some other material impermeable to liquids. This latter preference is made to allow the bolster 30 to be wiped dean and dry should the infant 14 bring moisture to saturate and soil the infant sleep support 10.
FIG. 4 shows another embodiment of the invention in which an infant sleep support 110 has a pillow 118 against which an infant 114 supports its back. A sheet base 116 extends from the pillow 118 sufficiently to allow the sheet base 116 to be tucked under a mattress 112. Extending from the back of the pillow 118 is a sheet flap 120 which also extends to a sufficient length for tucking it under the mattress 112. Fasteners 124 may be placed on the underside of the sheet base 116 and fasteners 126 on the top side of the sheet flap 120 so that this embodiment may also be arranged to enclose fully the interior of the pillow cover 122 housing a bolster 130 in the manner of the earlier embodiment, should this be preferred instead of tucking the sheet base 116 and sheet flap 120 beneath the mattress 112.
Referring now to FIG. 5, yet another embodiment of the infant sleep support 210 is seen to have a pillow 218 and a sheet base 216. A sheet flap 220 extends beneath the sheet base 216 in the manner of the embodiment shown in FIG. 2. An additional element of an abdominal brace 240 is attached to the joinder of the pillow cover 222 and the sheet base 216. The brace 240 may be detachably connected to the pillow cover and sheet base 216 by suitable detachable fastening means such as Velcro™ fastener or other suitable fastening means, not shown. Attached to the upside of the abdominal brace, with respect to the orientation of the infant sleep support 210 as it is placed on the mattress, are fasteners 242 and 244, fastener 244 being disposed at an end portion of abdominal brace 240 and fastener 242 being disposed between fastener 244 and the joinder of the pillow cover 222 and the sheet base 216. Attached to the cylindrical front surface of the pillow cover 222 is a diaper strap 246. The diaper strap 246 extends from the cylindrical surface of the pillow cover 222 and at its free end portion is a fastener 248, which is complementary to the fastener 242. On the top side of the cylindrical surface of the pillow cover 222 is a fastener 250 which is complementary to fastener 244.
Referring now to FIG. 6, there is seen an infant 214 resting upon the infant sleep support 210, and more particulary, on the sheet base 216 and the abdominal brace 240. The diaper strap 246 is threaded between the legs of the infant 214, and fastener 248 is attached to fastener 242.
Referring now to FIG. 7, it is seen that the infant 214, placed as shown in FIG. 5, is captured by pulling the abdominal brace 246 upwards and around the infant 214 and attaching fastener 244 to fastener 250. The infant 214 is now secured in place. The diaper strap 246 secures the infant 214 against wiggling downwardly so as to endanger the infant by the abdominal brace 240.
FIG. 8 shows an alternative design for the bolster 330. In this alternative design the outer cover 336 is still preferably made of a protective covering as a barrier against liquids. The inner core 334, however, is a single piece of foam such as foam rubber or foam plastic.
Other embodiments of the infant sleep support are disclosed by including mechanisms such as an insulated heating mechanism within the bolster to warm the infant or a low level vibrator. Thus, the infant sleep support provides for comfort to the child as well as protection against the child rolling on its stomach which consequences are taught by pediatricians to be better avoided. Furthermore, the infant sleep support may be used as a training device to train older children to sleep in a bed without protective sides.
With respect to the embodiments of FIGS. 1-4 inclusive, it should be appreciated that a strap or encircling means 240, as shown in FIGS. 5 and 6, may be used. Thus, the strap or encircling means has one end either permanently fixed to or removably attached to the bolster 22. When a removable strap is provided, the parent has an option or choice to use the infant support system with or without the detachable strap or encircling means.
Any embodiment of the invention that has been described in detail may be subjected to modifications and other embodiments incorporating the inventive features. Accordingly, it is intended that the foregoing disclosure is to be considered as illustrating the principals of the present invention as an example of those features and not as a delimiting description, which is the purpose of the claims that follow.
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An infant sleep support supports a sleeping infant at its back and holds the infant so that the infant will sleep on its side. The sleep support has a fabric sheet on which the infant sleeps and a pillow against which the infant supports its back. The sleep support has a pillow cover with an opening on its underside, with the opening closeable by a flap attached to the back of the pillow cover. In one embodiment the sheet and the flap are of sufficient length for tucking both the sheet and the flap beneath a mattress on which the infant sleep support is laid.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
In the reaction by the use of an immobilized lipase, such heterogeneous substrates as an oily substrate and a water-soluble substrate are caused by mass transfer to reach a lipase held fast in a particulate immobilizing carrier, undergo transformation into heterogeneous products, i.e. an oily product and a water-soluble product, by the lipase, and depart from the lipase again by mass transfer. This invention is directed to a method for performing the reaction advantageously by enabling the mass transfer of the continuous-phase substrates to proceed efficiently and continuously.
The lipase is an enzyme which acts upon ester bonds and, as such, finds utility in such reactions as ester hydrolysis, ester synthesis, and transesterification. It is also utilized for the optical resolution of racemic esters, acids, and alcohols. Thus, the lipase is expected to find extensive utility in various applications in the oil and fat industry, the pharmaceutical industry, and the foodstuff industry, for example.
2. Prior Art Statement
A method which, by the use of a column packed with a photolinkable gel entrapping an immobilized lipase, carries out the reaction by preparatorily mixing water and an oil by stirring and circulating the resultant oil-water mixture in the form of emulsion to the column has been known to the art [Y. Kimura et al., Eur. J. Appl. Microl. Biotechnol., 17, 107 (1983)]. Besides, a method which, by the use of an immobilized lipase column developed earlier by the inventors, carries out the reaction by continuously feeding into the column a water-soluble substrate via a middle upper stage and an oily substrate via a middle lower stage respectively and collecting continuously an oil product through the upper end of the column and a water-soluble product through the lower end thereof (Kosugi et al.; U.S. Pat. application Ser. No. 586,563, dated Mar. 6, 1984, now abandoned) and a method which, by the use of a multistage reaction vessel, effects the reaction by alternately repeating separation and mixture of an immobilized lipase, an oily substrate, and a water-soluble substrate thereby bringing the oily substrate and the water-soluble substrate into counterflow contact with the immobilized lipase (Kosugi et al.; Japanese Patent Public Disclosure SHO 63(1988)-59896) have been known to the art.
The known method which involves the circulation of a preparatorily emulsified mixture to the immobilized lipase column cannot be easily carried out in the form of a continuous operation because the emulsion particles are diffused inside the immobilizing carrier at a notably low speed and, therefore, the reaction solution must be circulated to the immobilized lipase column time and again. Moreover, this method is incapable of separately collecting the oily product and the water-soluble product continuously.
The method which involves the counterflow supply of the oily substrate and the water-soluble substrate to the immobilized lipase column is required to secure a flow path adapted for the oily substrate and the water-soluble substrate to be advanced as preparatorily mixed with each other so as to preclude the phenomenon of channeling, i.e. complete separation of the flow path of the oily substrate from that of the water-soluble substrate inside the column, and also is required to operate the column in such a manner that the feed rate of the substrates will be lower than the speed of separation between the water and the oil inside the column. Thus, this method is subject to numerous operational restrictions and, therefore, cannot easily make full use of the activity of the immobilized lipase.
The method which, by the use of the multistage reaction vessel, effects the reaction by alternately repeating separation and mixing of the immobilized lipase, the oily substrate, and the water-soluble substrate thereby bringing the oily substrate and the water-soluble substrate into counterflow contact with the immobilized lipase primarily consists in a batchwise operation of the multistage reaction vessel. For this method to produce a continuos reaction and permit continuous collection of the oily product and the the water-soluble product, therefore, the reaction vessel requires a complicated piping system and the operation of this piping system requires a complicated control. Further, the mixing of the three components inevitably entails formation of a fine emulsion, rendering it difficult to separate the oil from the water. If the separation and the mixing were carried out in two separate reaction vessels to preclude the difficulty of the separation, the operation would necessitate a separation time in addition to the reaction time and could hardly be called an efficient method.
The inventors have already developed an immobilized lipase capable of retaining the activity thereof even in the presence of a higher fatty acid and have demonstrated that this immobilized lipase permits continuous protracted use (U.S. Pat. application Ser. No. 586,563, dated Mar. 6, 1984). Since this immobilized lipase uses as its carrier an ion exchanger specifically developed with a view to lowering the head loss of the liquid inside the column. Thus, this immobilized lipase is not suitable for the fluidized bed to be used in the method of the present invention.
As an example of the immobilized lipase used in the form of a fluidized bed, the use of a lipase immobilized in stainless steel beads of a large specific gravity has been reported. In the reported experiment, hydrolysis of a tributyrin emulsion is carried out in a fluidized bed reactor keeping the immobilized lipase in a floating state therein [R. B. Liberman et al.; biotechnol. Bioeng., 17, 1401 (1975)].
The above mentioned method causes the emulsion of substrates to flow up and circulate through a mass of fine beads of immobilized lipase having a large specific gravity. It is, therefore, not free from the influence of the resistance offered to the diffusion of the emulsion particles inside the carrier, is incapable of producing a perfect continuous reaction, and is unable to effect separate collection of the oily product and the water-soluble product. If the immobilized lipase of a large specific gravity is used in the method of the present invention, the possibility ensues that the immobilized lipase will be discharged in conjunction with the water-soluble product of a large specific gravity.
OBJECT AND SUMMARY OF THE INVENTION
The inventors have perfected this invention after continuing a study directed to the elimination of the drawbacks standing on the way of realizing practical use of the prior techniques mentioned above.
To be specific, this invention is directed to a method for continuous reaction of a water-soluble substrate and an oily substrate in the presence of an immobilized lipase kept in the form of a fluidized bed, which method comprises providing an upper and a lower separation region respectively for separation of a water soluble substance and an oily substance vertically kept apart from each other, lipase reaction zones each containing the immobilized lipase in the fluidized state and incorporating therein agitating means and zones for the separation of an oily substance and a water soluble substance alternately disposed between the upper and lower separation regions, feeding the water-soluble substrate into the upper part of the uppermost lipase reaction zone and the oily substrate into the lower part of the lowermost lipase reaction zone, causing the immobilized lipase to fluidize and to come into mutual counterflow contact with the oily substrate and the water-soluble substrate in the lipase zone and recovering the oily product containing liquid from the upper part of the separation region and recovering the water-soluble product-containing liquid from the lower part of the lower separation region.
In accordance with the method of this invention, the reaction of the substrates by the immobilized lipase and the separation of the oily product and the water-soluble product of the reaction are continuously carried out. Specifically, the substrates each in the form of a continuous phase are supplied under agitation and consequently caused to undergo the reaction and give rise to an emulsion in the form of a discrete phase. This emulsion renders difficult the separation of the oil and the water. The present invention solves the problem due to the emulsion by providing reaction zones and zones for the oil-water separation which are vertically connected. Moreover, the method of the present invention permits continuous enzymatic reaction and continuous separate collection of the oily product and the water-soluble product of the reaction. Actually there are times when the oily product and the water-soluble product which are collected after the enzymatic reaction possibly contain respective unaltered substrates.
By supplying the oily substrate at a feed rate higher than the feed rate at which the water-soluble substrate is supplied, continuous concentration of the water-soluble product can be realized. Optionally, the products (possibly containing respective unaltered substrates) of the enzymatic reaction may be partly used as the substrates for supply to the reaction zone. By using the water-soluble product repetitively as a feed substrate at a high rate, for example, it is made possible to diminish the resistance offered to the external diffusion during the approach of the substrate to the carrier and effect the reaction with enhanced efficiency. When the water-soluble product is circulated as a feed substrate, since it is not acquired as a product, continuous manufacture of this product is no longer attained. The production in this case, therefore, is attained continually. By lengthening the time of this circulation, it becomes possible to attain concentration of the water-soluble product of the reaction.
The inventors have continued a study in search of a process for producing an immobilized lipase suitable for use in the method of this invention. It has been consequently ascertained to them that an immobilized lipase produced by causing a fine hydrophobic carrier possessing particle diameters in the range of 0.02 mm to 0.3 mm to immobilize therein a lipase and allowing an anion exchange residue binding no lipase molecule to be deposited on the surface of the carrier is highly effective in carrying out the enzymatic reaction. For the method of the present invention, it is necessary to dispose in each of the boundaries between the alternating lipase reaction zones and zones for the separation of the oily substance and the water soluble substance a mechanism such as, for example, a sieve which is pervious to a liquid substance and impervious to the immobilized lipase. When the particulate carrier has particle diameters exceeding 0.02 mm, the possibility of the carrier passing through the sieve need not be taken into consideration. Moreover, the immobilized lipase is both hydrophilic and hydrophobic and, on gradual adsorption of water or oil, is caused to vary in specific gravity. Thus, it serves the purpose of immobilized lipase from flowing out of the reaction system. When the particulate carrier has particle diameters not exceeding 0.3 mm, though it is liable to adhere to the reaction vessel and gather into coarse particles, it improves mass transfer of heterogenous substrates. The immobilized lipase thus obtained has high lipase activity, because of the high ratio of immobilization and performs the enzymatic reaction with high efficiency.
The above and other objects and features of the invention will become more apparent from the following detailed description with reference to the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
The drawing illustrates a typical apparatus for working the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now, the present invention will be described more specifically below with reference to the accompanying drawing illustrating a typical apparatus for working the present invention. In the diagram, reference numeral 1 stands for an outlet for an oily product-containing liquid, 2 for an upper separation region, 3 for an inlet for feeding a water-soluble substrate, 4 for a agitating blade, 5 for a separation zone, 6 for a lipase reaction zone, 7 for an inlet for feeding an oily substrate, 8 for a lower separation region, 9 for an outlet for a watersoluble product-containing liquid, 10 for a agitating shaft, 11 for a sieve plate disposed in the boundary between a lipase reaction zone and a dispersion zone, and 12 for a agitating shaft cover.
The upper separation region 2 and the lower separation region 8 are each desired to be in a conical shape. The conical shape is desirable because the fine emulsion possibly formed during the mixing of the two substrates is allowed to collide against the wall of the separation region before said fine emulsion reaches the outlet 1 for the oily product-containing liquid or the outlet 9 for the water-soluble product-containing liquid and break into a continuous phase before the emulsion in the form of discrete phase reaches the outlet, so that the separation of the oily phase from the aqueous phase is attained with enhanced ease. When the reaction solution is of such nature as to permit no easy separation of the oily phase from the aqueous phase or when the fine water particle suspended in the oily phase is subject to a protracted operation, the water particles may possibly be condensed and accumulated in the form of water drops in the transfer path for the oily product. When the separation regions mentioned above are provided each with a portion packed with glass beads for example, the fine emulsion in the form of discrete phase is broken into a continuous substance so thoroughly that the separation of the oily phase from the aqueous phase is accomplished substantially perfectly. For the efficiency of the separation of the water and the oil, the portion of stirring shaft is desired to be provided with the agitating shaft cover 12 and consequently prevented from the influence of the shaft. The upper separation region 2 is provided in the upper part thereof with the outlet 1 for the oily product-containing liquid and in the lower part thereof with the inlet 3 for feeding the water-soluble substrate. The lower separation region 8 is provided in the lower part thereof with the outlet 9 for the water-soluble product-containing liquid and in the upper part thereof with the inlet 7 for feeding the oily substrate. As described above, the separation regions are each disposed between the inlet for the substrate and the outlet for the product. Owing to this particular setup, the substrate is prevented from being entrained by the product. The separation zones and the separation regions are desirably kept at a temperature exceeding 50° C., because this temperature is proper for the separation of the oily phase from the aqueous phase and also is effective in preventing the relevant portions of the reaction vessel from pollution with infections microbes. They are desired to be provided as with a jacket so as to be maintained at the temperature above 50° C.
For this invention, a cylindrical reaction vessel can be used which is provided with agitating means in each of the lipase reaction zones. In this reaction vessel, there is placed the immobilized lipase. The agitating means is desired to be an angled paddle shaft of large size capable of producing a gentle agitating motion such as to decrease the possible physical breakage of the immobilized lipase. It is further desired to be capable of stirring the interior of the reaction vessel in the direction of inducing floatation of the immobilized lipase. The lipase reaction zones are adapted so as to be kept at a prescribed temperature. The sieve plates 11 which separate the separation zones 5 and the lipase reaction zones 6 are desired each to be something like a stainless steel sieve plate containing meshes so small as to preclude passage of the immobilized lipase. There is the possibility that the bubbles adhering to the immobilizing carrier will gather into large masses beneath the sieve plates 11 at the outset of the reaction and interfere with smooth progress of the separation of the oily phase from the aqueous phase in the reaction vessel. To preclude the trouble, the bubbles must be withdrawn by physical stimulation or by the use of deaeration means which is installed exclusively for this purpose.
As the separation zones 5 to be formed in the middle stage of the apparatus for working this invention, there can be generally used tubular enclosures having height enough to permit effective separation of the oil and the water. If these enclosures have an unduly large height, the oil-water separation consumes much time and the apparatus as a whole assumes a large inner volume. The separation zones, therefore, are desired to have as small a height as permissible In order for the water-oil separation to proceed smoothly, the agitating shaft part is desired to be provided with the agitating shaft cover 12 adapted to prevent the stirring shaft from the influence of the shaft. The fact that the apparatus is provided with a plurality of a lipase reaction zone 6 and a separation zone 5 is effective in curbing the occurrence of fine emulsion in consequence of protracted agitating of the heterogeneous substrates.
The term "oily substrate" as used in this invention refers to a substrate for the reaction to be caused by the immobilized lipase. As examples of the substrate, such substances as oils and fats, waxes, phospholipids, various esters, monoglycerides, diglycerides, and fatty acids which are hardly soluble in water may be mentioned. The substrate has a smaller specific gravity than water and is soluble in such nonpolar solvents as isooctane, hexane, and heptane. In conjunction with the oily product, this oily substrate forms an oily phase. The substrate which incorporates therein the aforementioned nonpolar solvent for the purpose of facilitating the oil-water separation or solubilizing the substrates is also included as an oily substrate. The term "water-soluble substrate" as used herein refers to water, a water-soluble organic substance such as glycerin, glycerophosphoric acid, or an aqueous solution of the organic substance. In conjunction with the water-soluble product, this water-soluble substrate forms an aqueous phase.
The lipase to be used for this invention is an enzyme produced by microorganisms or higher animals or plants. It is a biochemical macromolecular compound which acts on ester bonds and induces ester resolution, transesterification, or ester synthesis. The substances which exhibit this activity and are called esterases or phospholipases are also included as lipases.
Now, the method for causing the reaction of the present invention will be described below. The immobilized lipase is placed in the lipase reaction zones 6 provided with agitating means and kept fluidized by agitating and countercurrent flow and, at the same time, the oily substrate is supplied via the inlet 7 for the oily substrate and water-soluble substrate via the inlet 3 for the water-soluble substrate. As a result, the two substrates are brought into contact with the lipase and the water-soluble product is obtained via the outlet 9 for recovery of the water-soluble product and the oily product via the outlet 1 for the oily product-containing liquid. Let us assume that a high acid value oil is supplied as an oily substrate and glycerol as a water-soluble substrate. When the unaltered glycerol containing water is removed at a speed substantially equal to the feed rate of glycerol, a mixture of monoglyceride and triglyceride issues via the outlet for the oily product. Since the unaltered glycerol contains the water which is generated during the synthesis of glyceride, it is subjected to vacuum distillation for expulsion of the water. The residue of the vacuum distillation is used as a water-soluble substrate. As demonstrated in one working example, an oil is supplied as an oily substrate and water as a water-soluble substrate. When the water-soluble product is collected at a speed substantially equal to the feed rate of the water-soluble substrate, a mixture of a fatty acid and glyceride issues via the outlet for the oily product. When the water-soluble substrate is supplied at a rate lower than the feed rate of the oily substrate, continuous concentration of glycerin as the water-soluble product can be realized. To determine the highest possible concentration in which the glycerin is recovered, an experiment of the addition of glycerin has been made. The results of this experiment indicate that virtually no change is observed in the ratio of hydrolysis of oil even when the concentration of the recovered glycerin is increased to the range of 30 to 50%. Further it is realized that the concentration of glycerin is possible by repetitively using the water-soluble product as a water-soluble substrate for a long time. In the above case the ratio of hydrolysis of the oil is increased by increasing the feed rate of the aqueous phase (water-soluble substrate) to about 30 times that of the oil phase (oily substrate). And when the aqueous phase is repetitively used for a long time, the otherwise inevitable deterioration of the color tone of the oily product can be precluded by divesting the aqueous phase of impurities as with activated carbon.
The immobilizing carrier for the lipase of the present invention is desired to be of a type not easily worn because the immobilized lipase forms a fluidized bed and is agitated. The immobilization of the lipase can be carried out by any of the conventional methods such as the carrier immobilization method and the entrapping method which have been available for the immobilization of enzymes. Particularly desirable for the present invention is the immobilized lipase which has the enzyme immobilized in a fine hydrophobic carrier possessing particle diameters in the range of 0.02 to 0.3 mm and an anion-exchange group binding no lipase molecules on the carrrier. The term "hydrophobic carrier" as used herein refers to a carrier in the form of a macroporous ion-exchange resin. An amphiphilic carrier is obtained by introducing the anion-exchange group in the largest possible amount into the hydrophobic carrier mentioned above. For use in the method of the present invention, the amphiphilic carrier is desired to be of such nature that it will gain in specific gravity and sink in the upper-layer liquid (oily substance) after it has adsorbed the lower-layer liquid (water-soluble substance) of large specific gravity, whereas it will lose in specific gravity and float in the lower-layer liquid (water-soluble substance) after it has adsorbed the upper-layer liquid (oily substance). Generally, numerous species of anion-exchange resins exhibit the nature of an amphiphilic carrier. Any of these anion-exchange resins can be used for the present invention so long as it possesses the nature mentioned above. As concrete examples of the anion-exchange resin, such proprietary commodities as Dowex MWA-1 and Dowex 66 (Dow Chemical Company), Amberlite IRA 93 (Rohm and Haas Company), Diaion HPA 25 (Mitsubishi Chemical Industries, Ltd.), and Lewatit MP 64 (Bayer AG) may be mentioned. The anion-exchange resin is desired to possess particle diameters in the range of 0.02 to 0.3 mm. The immobilization of a lipase with the anion-exchange resin is attained by causing a solution containing an amount of lipase which is less than the number of atoms equal to one-thousandth of the ion-exchange capacity of the anion-exchange resin to come into contact with the anion-exchange resin.
For the immobilization of the lipase to be obtained with greater fastness, the immobilized lipase is further treated with such a polyfunctional reagent as glutaraldehyde, for example. Since this polyfunctional reagent produces an undesirable effect in food, the immobilized lipase treated therewith for the purpose mentioned above is desired to be thoroughly deprived of the excess polyfunctional reagent as with a reducing agent and then washed amply with water.
This invention characteristically aims to provide a method for continuous reaction which enables the reaction between the oily substrate and the water-soluble substrate and the separation of the oily product from the water-soluble product to proceed simultaneously. For the oily substrate and the water-soluble substrate to react with each other in such a manner as to alleviate the resistance offered by the immobilized lipase to the external diffusion, it is necessary that the speed of motion of the two substances on the surface of the immobilized lipase should be sufficiently high. For this purpose, the immobilized lipase, the oily substrate, and the water-soluble substrate must be agitated. When this agitation is continued unduly long, however, the oily substrate and the water-soluble substrate are transformed into an emulsion and the particles of this emulsion enter the pores of the immobilized lipase only with difficulty and, as a result, the resistance to internal diffusion is increased. Thus, the emulsion produced by the agitation must be broken up into an oily substrate in the form of a continuous phase. To fulfill this necessity, the lipase reaction zones 6 provided with agitating means and the separation zones 5 are alternately disposed in the vertical direction in the reaction region so that the fine emulsion possibly produced by the agitation will be broken up in the separation zones to such an extent as to facilitate the oil-water separation and ensure supply of the substrate in the form of a continuous phase to the subsequent lipase reaction zones. The seive plates 11 separating the separation zones 5 and the lipase reaction zones 6 are desired to be made of metal. For the recovery of the oily product and the water-soluble product, the reaction vessel is provided at the upper and lower ends thereof respectively with separation regions 2 and 8. By providing these separation regions each with emulsion breaking means provided with a portion packed with glass bead for example, the products which have undergone substantially complete oil-water separation are obtained. The oil-water separation proceeds with the breakage of the emulsion particles. This breakage of the emulsion proceeds with creaming, cohesion, and union. Since the speed of this oil-water separation more often than not is governed by the Stokes' law, the acceleration of the oil-water separation may be possibly obtained by increasing the diameter of the emulsion particles, increasing the difference of density between the oil and the water, lowering the viscosity of the dispersion medium, or heightening the gravitational velocity by exertion of centrifugal force, for example.
The mass transfer of the substrates and the corresponding products relative to the immobilized lipase can be divided into internal diffusion and external diffusion. The transfer of the substrates toward the enzyme molecules immobilized inside the immobilizing carrier and the transfer of the products produced by the enzyme molecules to the exterior of the immobilizing carrier make up the internal diffusion. When the fineness of the immobilizing carrier is increased, the distance of transfer is shortened and the impact of the resistance to the internal diffusion alleviated. The transfer of the substrates en route to the surface of the immobilizing carrier and transfer of the corresponding products away from the surface of the immobilizing carrier make up what is called the external diffusion. Where the immobilized lipase carrier is caused to form a fluidized bed as contemplated by the present invention, the floating speed of the immobilized lipase carrier in the reaction solution is increased, the transfer speed of the reaction solution relative to the surface of the immobilizing carrier increased, and the impact of the external diffusion resistance alleviated in proportion as the fineness of the immobilizing carrier is enhanced If the immobilizing carrier has particle diameters of not more than 0.02 mm, however, the reticular structure of the sieve plates precludes the leakage of the carrier particles only with difficulty. In this case, it is also difficult to keep the state of fluidization of the carrier particles within a fixed range by virtue of the difference of specific gravity between the two substrates. It is the nature of the immobilized lipase to adhere to the wall of the reaction apparatus or mutually cohere by adsorption to give rise to coarse masses If the immobilizing carrier has particle diameters exceeding 0.3 mm, said adverse phenomena peculiar to any fine powder more than offset the effects manifested in the improvement of mass transfer.
For the immobilizing carrier to offer a sufficient surface for entrapping the enzyme, it is required to possess a porous texture. The pores of the immobilizing carrier have diameters approximately in the range of 10 to 100 times (10 2 ↑ to 10 4 ↑) the diameter of the enzyme molecules. When the carrier has sufficient fineness, the pores formed therein have small depth sufficient to permit easy immobilization of the enzyme. Consequently, the efficiency of immobilization is enhanced.
Moreover, since the present invention uses the immobilized lipase beads in which lipase molecules and anion-exchange groups coexist, a fatty acid possibly occurring in the reaction solution does not lower the pH value in microenvironment of the enzyme. Thus, the reaction is allowed to proceed even in the presence of a higher concentration of fatty acid. Further, since the enzyme molecules are hydrophobically or ionically linked in a multipoint pattern to the hydrophobic carrier, the immobilized lipase is enabled to offer ample resistance to chemically degenerating substances and prevent leakage of enzyme over a long period of continued use.
EXAMPLE 1
The lipase produced by Pseudomonas fluorescens biotype I-No. 1021 (Bikoken Deposit FERM-P No. 5495 dated Apr. 22, 1980; Budapest Treaty Deposit No. FERM BP-494 dated Mar. 1, 1984) was obtained from the broth, concentrated, and treated with acetone to prepare a partly refined product, i.e. a lipase possessing a specific activity of 504 units/mg of protein. This lipase was adsorbed on a carrier (product of Dow Chemical Company and marketed under tradename designation of "Dowex MWA-1") at an amount of 1,185 units of lipase per g of carrier. The composite of the carrier and the adsorbed lipase was treated with glutaraldehyde to strengthen the linkage, washed with water, and then dried by being suction filtered over a glass filter.
Then, a reaction apparatus constructed as illustrated in the diagram was prepared. In the apparatus, lipase reaction zones 6 and separation zones 5 were partitioned each with a stainless steel sieve plate 11 (160 mesh). This reaction apparatus was encircled with a jacket (not shown) so as to be maintained at a fixed temperature of 60° C. It was provided at the upper and lower ends thereof respectively with conical separation regions 2 and 8, between the upper separation region 2 and the uppermost reaction zone with an inlet for introducing a water-soluble substrate, at the apex of the separation region 2 with an outlet 1 for issuing of an oily product, and between the lower separation region 8 and the lowermost reaction zone with an inlet 7 for introducing an oily substrate at the bottom of the separation region 8 with an outlet 9 for issuing of water soluble product. Inside the apparatus, the separation zones 5 and the reaction zones 6 were alternately disposed in the vertical direction. These zones are 100 mm in diameter and 30 to 31 mm in height each. The reaction zones were each charged with 35 g (in dry weight) of the aforementioned immobilized lipase. They were each provided with a paddle type agitating blade 4 inclined at an angle of 45 degrees and adapted to produce 10 complete rotations per 77 seconds so as to keep the immobilized lipase beads floating. A stirring shaft 10 was covered with a stirring shaft cover 12 in the portions outside the reaction zones.
At first, water and olive oil were each supplied at a flow rate of about 10 ml/hour to the reaction apparatus, with the agitating blades kept idle and the outlet 9 for release of water-soluble product kept closed. After the reaction vessel was filled to capacity with the water and olive oil, the agitating blades were set rotating and the supply of water at a rate of 2.5 ml per hour and the supply of olive oil at a rate of 5 ml per hour were started. When the recovery volume of the water-soluble product via the lower end was adjusted to 2.5 ml per hour, the oily product was obtained via the upper end at a rate of about 5 ml per hour.
After the elapse of 525 hours following the start of the reaction, the reaction was continued at a fixed temperature of 60° C. After the elapse of 762 hours following the start of the reaction, the feed rate of water was kept at 0.8 ml/hour and that of olive oil at 1.5 ml/hour until after the elapse of 1,201 hours. Then after the elapse of 1,550 hours following the start of the reaction, the reaction was continued again with the feed rate of water fixed at 2.5 ml/hr and that of olive oil at 5.0 ml/hr. The changes in the olive oil hydrolysis ratio and the glycerin concentration during the course of this operation were as shown in Table 1. The ratio of hydrolysis was determined by the method described in Example 2 and the glycerin concentration by the colorimetry using periodic acid. Though the first sign of physical breakage of the immobilized lipase was observed after the reaction lasted for about one month and a half, the possible leakage of immobilizing carrier was substantially completely prevented owing to the amphiphilicity of the carrier.
TABLE 1__________________________________________________________________________Reaction time (hrs) 525.2 698.2 762.0 1032.2 1141.1 1201.0 1555.0 1842.3Feed rate of olive oil (ml/hr) 5.0 → 1.5 → → → 5.0 →Hydrolysis rate of oily product (%) 77.5 79.1 79.4 83.5 83.0 82.7 84.9 71.7Feed rate of water phase (ml/hr) 2.5 → 0.8 → → → 2.5 →Glycerol concentration in water phase 108.7 110.5 124.3 147.3(mg/ml)__________________________________________________________________________
It is clearly noted from Table 1 that the decline of the hydrolysis ratio of oil was less than 10% even after about two months' continued operation at 60° C. and that the glycerol concentration was increased by decreasing the feed rate of the water layer to half of that of the oil layer.
With the feed rate of the oil phase fixed and that of the water phase increased from 0.8 ml/hr to 24 ml/hr, the water-soluble product was circulated to the reaction apparatus as a water-soluble substrate. The results of this operation were as shown in Table 2.
TABLE 2__________________________________________________________________________Reaction time (hrs) 762 1032 1141 1201 1219 1289 1312 1344 1438Feed rate of oily phase (ml/hr) 1.5 → → → → → → →Feed rate of aqueous layer (ml/hr) 0.8 → → → 24 → → → →Resolution ratio of oil (%) 7.94 83.5 83.0 82.7 84.0 85.4 86.6 86.7__________________________________________________________________________
It is clearly noted from this table that the hydrolysis ratio of oil was improved when the feed rate of the aqueous phase was increased to 30 times the original feed rate. This improvement may be logically explained by a supposition that the impact of the external diffusion resistance was eliminated by the increased feed rate of the aqueous phase.
After 2057.6 hours' operation, the reaction was continued in the absence of agitation to study the influence of agitation upon the reaction. The results were as shown in Table 3.
TABLE 3__________________________________________________________________________Reaction time (hrs) 1792.5 1816.5 1842.3 2057.6 2154.9 2178.4 2205.7 2231.4 2304.5Resolution ratio of oil (%) 71.9 72.3 71.1 63.1 62.3 60.8 61.3 63.0Presence of agitation yes → → no → → → → →__________________________________________________________________________
It is clearly noted from this table that the hydrolysis ratio of oil was lower in the absence of agitation. The results indicate that the agitation eliminated the impact of the external diffusion resistance and, at the same time, promoted the oil-water separation in the reaction zones packed with the immobilized lipase. The immobilized lipase in the second layer was sampled after 2304.5 hours' (about 96 days') operation, and the sample was washed with a 2 : 1 mixed solution of benzene-acetone and tested for activity per unit weight. The results were as shown in Table 4.
TABLE 4______________________________________Immobilized lipase activity before the reaction 71.9 units/gImmobilized lipase activity after 2304.5 hours' 50.0 units/greaction______________________________________
It is clearly noted from this table that the residual activity of the immobilized lipase was about 70%.
EXAMPLE 2
An ion-exchange resin (total exchange capacity 4.2 meg/g min.) (product of Dow Chemical Company and marketed under tradename designation of "Dowex MWA-1) was pulverized in a mortar and separated by sieves to produce carriers of different particle sizes shown in Table 5. Of these carriers, 2-g portions were taken as specimens and subjected to the following treatment. First, the specimens was each mixed with 6 ml of the same lipase solution (5,640 units) as used in Example 1 and shaken overnight at 8° C. The resultant mixture and 0.32 ml of a 25% glutaraldehyde solution added thereto were shaken at 8° C. for 10 minutes. Subsequently, the resultant mixture and 0.8 ml of a 20% sodium hydrogen sulfite solution added thereto were shaken at 8° C. for 10 minutes, washed thoroughly with water, and dried on a glass filter, to produce a preparation having the lipase immobilized on a fine powder of Dowex MWA-1 as a carrier. The lipase purified to a specific activity 2,000 to 2,500 units/mg of protein, on analysis by the SDS electrophoresis, was found to possess a molecular weight of 120,000. The mol number of the 5,640 units of the lipase was as follows. ##EQU1##
The ratio of this number to the exchange capacity of the Dowex MWA-1 is found as follows.
4.2×2×10.sup.-3 /(2×10.sup.-8)=4.2×10.sup.5
This means that in the immobilized lipase, 4.2×10 5 anion-exchange groups per molecule of the lipase was present on the hydrophobic carrier.
Then, the immobilized lipase was tested to determine the ratio of immobilization of the lipase on the carrier. First, the lipase activity of the washings obtained by the aforementioned immobilized lipase was washed with water was tested by the modified Nord et al.'s method [Nichinoka, Vol. 36, page 860 (1962)]. The activity of the lipase adsorbed on the carrier was found by deducting the found value from the total activity, 6,540 units and the ratio of immobilization was calculated. Then, the immobilized lipase was tested for activity by the following method. In a conical flask having an inner volume of 50 ml, a reaction solution consisting of 2 g of olive oil, 0.2 ml of a 0.1 M phosphate buffer (pH 7), and the immobilized lipase (0.01-0.1 g) was shaken for reaction The reaction was stopped with 10 ml of a methanol-chloroform mixture (2:1). The resultant solution mixture was tested for the concentration of the produced fatty acid by titration with a liquid produced by dissolving 0.05 ml of NaOH in 95% methanol. In any case, one unit of lipase was fixed at an amount which liberated 1 micro mol of acid per minute at 60° C. at pH 7. The results were as shown in Table 5.
TABLE 5______________________________________Particle Activity of Ratio of Activity ofdiameter washings immobilization immobilized lipase(mm) (unit) (%) (unit/2 g)______________________________________ 0.02-0.037 3.1 99.8 66.40.038-0.177 6.3 99.9 69.00.178-0.300 391.0 93.1 31.80.301-0.840 483.0 91.4 25.40.841-1.68 756.2 86.6 15.0______________________________________
It is clearly noted from this table that the ratio of immobilization and the activity of the immobilized lipase were both enhanced as the fineness of the carrier powder increased.
Then, the ratio of hydrolysis was determined. In a conical flask having an inner volume of 100 ml and furnished with a silicon stopper, 1 g of live oil, 1 g of water, and the immobilized lipase (0.15-0.5 g) were shaken for reaction at 60° C. After the reaction, the immobilized lipase was washed with a 1:1 ethanol/benzene mixture on a filter paper No. 2 to extract the hydrolyzate. The extract was tested for acid value and saponification value. The ratio of hydrolysis was calculated based on the ratio of the two values mentioned above. The results were as shown in Table 6. The reaction involved in this experiment may well be regarded as faithfully representing the reaction in the fluidized bed using a large amount of the immobilized lipase.
TABLE 6______________________________________ Ratio of hydrolysis Reaction time 23.15 hr 120 hr 22 hr Amount of enzymeParticle diameter 0.15 g 0.15 g 0.75 g______________________________________0.02 mm-0.037 mm 63.4% 91.2% 89.8%0.038-0.177 48.7 78.2 90.80.178-0.300 36.7 61.5 85.20.301-0.840 53.9 76.0 86.60.841-1.68 59.4 81.5 88.7______________________________________
Generally when immobilized lipase beads of a small particle diameter are used in a large volume, they are reliable to adhere to the inner wall of the reaction vessel or cohere into large lumps. By this physical phenomenon, the hydrolysis effected by the lipase is impaired. When the particle diameter exceeds 0.3 mm, the aforementioned physical phenomena bring about a significant influence. It is clearly noted from Table 6 that when the particle diameter was not more than 0.3 mm, the increase of the activity of the individual immobilized lipase due to the size reduction more than offsets the decrease of the ratio of hydrolysis caused by the aforementioned physical phenomena due to the size reduction and that the ratio of hydrolysis increased in proportion as the fineness of the carrier powder increased. The data indicate that the immobilized lipase retained sufficient ratio of hydrolysis when the particle diameter was in the range of 0.02 to 0.3 mm.
EXAMPLE 3
An ion-exchange resin (produced by Dow Chemical Company and marketed under tradename designation of "Dowex MWA-1") was pulverized and separated to obtain two species of carrier, one possessing a particle diameter not exceeding 0.3 mm and the other a particle diameter exceeding 0.3 mm. Of these carriers, 2-g portions taken as specimens were each washed with water. The washed specimen and 3 ml of the same lipase liquid (2,820 units) as used in Example 2 were shaken overnight at 8° C. The resultant mixture and 3 ml of water and 0.32 ml of a 25% glutaraldehyde solution added thereto were processed in the same manner as in Example 2, to obtain an immobilized lipase on Dowex MWA-1. The immobilized lipase samples thus obtained were tested for activity of washings, ratio of immobilization, and activity of immobilized lipase by following the procedure of Example 2. The results were as shown in Table 7.
TABLE 7______________________________________Particle Activity of Ratio of Activity ofdiameter washing immobilization immobilized lipase(mm) (unit) (%) (unit/2 g)______________________________________ 0.02-0.300 59.0 97.9 151.60.301-1.68 780.9 72.3 43.3______________________________________
It is clearly noted from Table 7 that the carrier of greater fineness showed better results in ratio of immobilization and in immobilized lipase activity. Even when the volume of the lipase solution was decreased from 6 ml to 3 ml, the produced immobilized lipase exhibited high activity. Then, the immobilized lipase was tested for ratio of hydrolysis in the same manner as in Example 2. The results were as shown in Table 8.
TABLE 8______________________________________ Ratio of hydrolysis Reaction time 21.2 hr 58 hr Amount of enzymeParticle diameter 0.5 g 0.5 g______________________________________0.02 mm-0.30 mm 81.8% 96.3%0.301-1.68 (not pulverized) 65.5 86.4______________________________________
It is clearly noted from Table 8 that the carrier powder of greater fineness showed a higher ratio of hydrolysis.
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A water-soluble substrate and an oily substrate are continuously reacted with immobilized lipase in a reaction vessel having vertically maintained apart upper and lower conically-shaped regions, respectively, for separation of a water-soluble product and an oily product, a plurality of lipase reaction zones each containing immobilized lipase capable of being fluidized and an agitating means, and a plurality of intermediate separation zones for separation of an oily substance and a water-soluble substance. The lipase reaction zones and the intermediate separation zones are disposed alternately between the upper and lower conically-shaped separation regions. Boundaries between the lipase reaction zones and intermediate separation zones are pervious to liquid but impervious to the immobilized lipase. The water-soluble substrate and oily substrate are passed in counterflow contact through the lipase reaction zones and intermediate separation zones and mutually contact the immobilized lipase which has been fluidized. An oily product is recovered from the upper conically-shaped separation region and a water-soluble product is recovered from the lower conically-shaped separation region.
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FIELD OF THE INVENTION
The present invention relates to a firearm, which could be both long—as rifles—and short—like guns—, without the traditional trigger intended to be pressed by the index finger, and provided with thumb-operable means.
STATE OF THE ART
In the scope of the present invention, the expression ‘firearm’ is used to indicate all portable weapons, provided with a barrel, firing a bullet by the action of a firing pin activating the corresponding charge. As known, a small charge, or primer, is encapsulated in the bullets and, when suddenly compressed by the firing pin of the weapon, it explodes. The expansion of gases generated by the explosion pushes the bullet into the firearm barrel until ejecting it at high speed.
Firearms are defined “long” if intended for long distance shooting; these arms have a long barrel and they are shouldered by using both hands, and almost always using the shoulder as a support when taking aim and shooting. According to this definition, rifles are in fact long firearms.
Firearms are defined “short” if intended especially for a personal use against short distance targets; these firearms have a short barrel and usually are grasped using only one hand. According to this definition, guns and some machine-guns are in fact “short” firearms.
Currently, the butt, which allows to grip the firearm, extends from the main body that the afore said firearms are provided with; on the main body the barrel of the firearm is also mounted, which can be smooth or ribbed, and the breech, constituting the seat in which the bullets are loaded and where the respective primer is activated by the firing pin. The breech converges in the barrel to allow the bullet to be ejected forward. The firing pin is translatable in a corresponding seat between a backward position, at which it does not interfere with the bullet loaded in the breech, and a forward position, at which it is in abutment against the bullet loaded at the primer thereof. Usually, the firing pin is spring loaded in advance and blocked in a backward position.
The firearm is driven by means of a lever, usually called trigger, cantileverly extending from the firearm body and intended to be pushed by the index finger towards the butt. The firing pin release is controlled by the trigger through a kinematic system (i.e. an assembly of levers and/or cams and/or springs, etc.), either directly or by functionally interposing the firearm hammer, if the latter is present. Once released, the firing pin is pushed against the bullet, thus causing the primer explosion and the bullet to be discharged from the barrel itself.
For example, WO 2009/000218 describes a typical drive mechanism of a semi-automatic gun. Referring to FIG. 6 , the firing pin is referred to by numeral 39 and the trigger by 12 .
In traditional solutions, the overall bulk of the kinematic system functionally interposed between the trigger and the firing pin, or between the trigger and the firearm hammer, represents a drawback. Since the body of the gun houses the kinematic system, between the trigger and the breech, the greater is its overall dimension, the greater is the distance between the barrel and the trigger.
FIG. 1 shows a schematic side view of a traditional gun 1 ′ provided with a barrel 2 ′ and a butt 3 ′, allowing the user to grasp the firearm. The gun 1 ′ is provided with a traditional T-shaped trigger cantileverly extending downward, substantially parallel to the butt 3 ′. The trigger is designed to be pressed, i.e. pushed towards the butt 3 ′, by the first finger f 1 ; the butt 3 ′ is designed to be grasped in the hand by the other fingers f 2 . The distance d 1 between the first finger and the longitudinal axis of the barrel 2 ′ is defined as ‘aiming distance’ or ‘line of fire’. The distance d 2 between the middle finger and the longitudinal axis of the barrel 2 ′ is defined as ‘strong-grasp distance’.
In conventional firearms, the aiming distance d 1 is generally greater than 33 mm, generally equal to about 45 mm.
The strong-grasp distance d 2 is mostly between 55 mm and 65 mm. The greater the strong-grasp distance d 2 is, the more tangible and intense the firearm recoil after a shot is. In fact, during firing, as a result of the charge in the bullet being triggered, a reaction force F parallel to the forward direction of the bullet, i.e. parallel to the axis of the barrel 2 ′, is generated, and is directed towards the user. De facto, the strong-grasp distance d 2 is the arm of the force F; as a result, a moment M=F×d 2 is generated which, according to right-hand rule, tends to raise the barrel upward. The accuracy of the shot can be negatively affected by this phenomenon.
It is therefore desirable to minimize the distance d 2 .
Document FR 2588369 describes a firearm provided with a trigger positioned laterally to the butt, on the right and left thereof. The trigger is rotatable around an axis orthogonal to the firearm barrel to be operated by the thumb of the hand. The firearm has not the traditional trigger operable by the index finger.
U.S. Pat. No. 1,372,763 describes another solution known in the art.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a firearm able to simply and effectively solve the drawbacks of the traditional solutions, being at the same time simple to be manufactured and safe for the user.
These and other objects are obtained by a firearm according to claim 1 .
In particular, the present invention relates to a firearm, for example a gun or rifle, comprising a main body; a barrel and a butt (or handle, or helve) are constrained to the main body.
In the firearm there is a seat wherein the firing pin is housed. The latter is translatable between a backward position, at which it does not interfere with the bullet loaded in the barrel and the firearm is at rest, and a forward position, at which the firing pin is in abutment against the bullet loaded in the barrel thus activating its primer.
The firearm comprises a drive mechanism of the firing pin, i.e. a mechanism operating to control the displacement of the firing pin under control of the user, i.e. the person grasping the firearm. The drive mechanism comprises in its turn a trigger and levers and/or gears and/or elastic elements.
The firearm is different from the known art because the trigger is positioned on a firearm side, substantially laterally with respect to the barrel or butt, to be pushed by the thumb of the hand.
In other words, the firearm according to the present invention is free of the traditional trigger that substantially extends cantileverly from the firearm body in parallel to the butt and downward, in the median plane of the firearm itself.
In the firearm according to the present invention, the butt is shaped so as to be tightened in the hand by the index, middle, ring and little fingers. Indeed, the index finger, not having to push any trigger, can be used to grasp the butt.
Preferably, the trigger is positioned at the upper portion of the butt, just below the longitudinal axis of the barrel.
This technical solution offers several advantages.
First of all, the vertical bulk of the drive mechanism is minimized with respect to what is found in firearms available nowadays.
For example, the suggested solution allows the firearm to be made with a structure such that the distance between the longitudinal axis of the barrel and the rotation axis of the trigger is shorter than 20 mm, and preferably shorter than 15 mm.
In particular, the distance d 1 is shorter than or equal to 20 mm, thus obtaining a firing line particularly low and therefore very accurate.
The described configuration gives an advantage also to the previously defined strong-grasp distance d 2 which, being the same as the aiming distance d 1 (d 2 =d 1 ), turns out to be shorter than or equal to 20 mm. The recoil effect is thus minimized because the arm d 1 of the fire force is shorter with respect to traditional solutions. All this promotes fire accuracy which is maximized with the other conditions unchanged.
Gripping the butt also by the first finger gives the additional advantage of strength and safety higher than traditional solutions, in which the first finger does not contribute to the grip but is used to press the trigger.
As clearly understood by the field technician, the trigger is positioned on the left side or the right side of the firearm, depending on whether the user is right- or left-handed, respectively. In an alternative solution the firearm has two triggers, one on each side.
Preferably, the trigger is rotating with respect to the body of the firearm on a rotation axis 90° skew with respect to the longitudinal axis of the barrel. The rotation axis is preferably in-between the longitudinal axis of the barrel and the butt, right in order to minimize the bulk.
In an embodiment of the present invention the firearm is a gun.
Advantageously, in addition to the trigger, the drive mechanism comprises a drive shaft fixed to the trigger and rotating on its rotation axis, a thrust cam, fixed to the drive shaft, a main lever having a first end hinged to the main body of the firearm, a thrust lever pivoted to the main lever at the second end, and a snap lever, pivoted to the main body and pivoted to the thrust lever and provided with means for temporarily retaining the firing pin. The rotation of the trigger leads to an equal rotation of the drive shaft connected thereto and of the thrust cam, the latter in its turn rotationally pushing the main lever in the opposite way; the rotation of the main lever leads to a corresponding roto-translation of the thrust lever, the latter in its turn rotationally pushing the snap lever up to cause the disengagement thereof from the firing pin. A spring of the firing pin applies a force to the firing pin itself, which is free to translate in the respective seat, pushing it against the bullet in the barrel. De facto, the firing pin is immobilized by the thrust lever that counters the spring action until the user operates the drive mechanism of the firearm, thereby releasing the firing pin.
Preferably, the firearm comprises more springs countering the rotation of the trigger and the snap lever. These springs are also used for returning the respective elements in the initial position in order to be activated again.
Preferably, the gun comprises at least another safety mechanism, or safety catch, having the purpose to inhibit the drive mechanism. The safety mechanism comprises in its turn at least one of the following solutions, or both of them.
In a first embodiment, the safety mechanism comprises a safety lever pivoted to the butt and rotating with respect thereto at its back portion, that is the portion facing the user when he/she grasps the firearm. Moreover, an elastic element countering the rotation of the safety lever is provided. In a first configuration, an end of the safety lever engages the snap lever and prevents the rotation thereof, and hence it prevents the activation of the firing pin. In a second configuration, the safety lever does not engage the snap lever, thereby allowing the activation of the firing pin. The switching from the first to the second configuration is caused right by the hand palm of the user when he/she grasps the butt of the firearm by overcoming the force of the countering elastic element.
In a second embodiment, the safety mechanism comprises a safety button at the front and upper portion of the butt, where the first finger is expected to be placed. The button is movable by the user's first finger, between an active position, next which the button engages the trigger and prevents the rotation thereof, and an inactive position, corresponding to the button pressed towards the butt and to the disengagement of the trigger, which is therefore free to rotate.
In another embodiment of the present invention the firearm is a rifle. For this embodiment, the Applicant reserves to file a divisional application, based on claim 9 , independently of what has been described relative to the gun.
Preferably, in the rifle the drive mechanism further comprises, in addition to the trigger, also a hammer pivoted to the main body. The hammer is rotating between an initial position, in which it is held by the trigger itself directly or by the interposition of other elements, and a final position contacting and pushing the firing pin, wherein the trigger does not hold the hammer, and wherein a preloaded spring pushes the hammer with violence towards the firing pin.
Preferably, the weapon comprises at least one safety mechanism inhibiting the drive mechanism, equivalent to one of the mechanisms described for the gun.
As clearly understood by the field technician, the present invention can be further applied to the field of toy weapons and weapons used in simulations, known as “Airsoft”. For example also a pneumatic toy weapon, or a firearm reproduction, can be operated by a trigger positioned laterally on the firearm.
BRIEF LIST OF THE FIGURES
Further characteristics and advantages of the invention will be more evident from a review of the following specification of a preferred, but not exclusive, embodiment, shown for illustration purposes only and without limitation, with the aid of the attached drawings, in which:
FIG. 1 is a schematic side view of a gun according to known art;
FIG. 2 is a side view of a gun according to the present invention;
FIGS. 3 and 4 are perspective partial views of the gun shown in FIG. 2 ;
FIGS. 5 and 6 are perspective partial views of the drive mechanism of the gun shown in FIG. 2 ;
FIG. 7 is an exploded view of the drive mechanism of the gun shown in FIG. 2 ;
FIG. 8A is a right side view of the drive mechanism of the gun shown in FIG. 2 in a first configuration;
FIG. 8B is an enlargement of FIG. 8C ;
FIG. 8C is a left side view of the drive mechanism of the gun shown in FIG. 2 , in the first configuration;
FIG. 9A is a right side view of the drive mechanism of the gun shown in FIG. 2 , in a second configuration;
FIG. 9B is an enlargement of FIG. 9C ;
FIG. 9C is a left side view of the drive mechanism of the gun shown in FIG. 2 , in the second configuration;
FIG. 10A is a right side view of the drive mechanism of the gun shown in FIG. 2 , in a third configuration;
FIG. 10B is an enlargement of FIG. 10C ;
FIG. 10C is a left side view of the drive mechanism of the gun shown in FIG. 2 , in the third configuration;
FIG. 11A is a right side view of the drive mechanism of the gun shown in FIG. 2 , in a fourth configuration;
FIG. 11B is an enlargement of FIG. 11C ;
FIG. 11C is a left side view of the drive mechanism of the gun shown in FIG. 2 , in the fourth configuration;
FIG. 12A is a right side view of the drive mechanism of the gun shown in FIG. 2 , in a fifth configuration;
FIG. 12B is an enlargement of FIG. 12C ;
FIG. 12C is a left side view of the drive mechanism of the gun shown in FIG. 2 , in the fifth configuration;
FIG. 13 is a schematic side view of a detail of the gun shown in FIG. 2 ;
FIG. 14 is a schematic side view of another detail of the gun shown in FIG. 2 ;
FIG. 15 is a top view of the detail shown in FIG. 14 ;
FIG. 16 is a schematic view of a first rifle according to the present invention;
FIG. 17 is a partial and sectional view of the drive mechanism of the rifle shown in FIG. 16 ;
FIG. 18 is an exploded view of the drive mechanism of the rifle shown in FIG. 16 ;
FIG. 19 is a schematic view of a second rifle according to the present invention;
FIG. 20 is a partial and sectional view of the drive mechanism of the rifle shown in FIG. 19 ;
FIG. 21 is an exploded view of the drive mechanism of the rifle shown in FIG. 19 .
DETAILED DESCRIPTION OF THE INVENTION
As previously mentioned, FIG. 1 is a schematic side view of a traditional gun.
FIG. 2 shows a gun 1 according to the present invention provided with a barrel 2 , having a longitudinal X axis, a slide 4 , a butt or grip 3 , and a trigger T positioned laterally on the firearm between the butt 3 and the slide 4 .
FIGS. 3 and 4 are, respectively, partial front and rear perspective views of the gun 1 , clearly showing the position and the respective bulk of the trigger T.
In FIG. 2 , f 1 refers to the vertical section of the first finger and 12 to the vertical section of the middle, ring and little fingers of the same hand of the user, overall. In view of the foregoing description, the trigger T is not engaged by the first finger, being conversely designed to be pressed by the thumb (not shown), i.e. rotated in the direction of the arrow R.
As will be explained with reference to the remaining figures, the trigger T controls a drive mechanism 5 of the firing pin 6 of the gun 1 . With respect to traditional solutions, wherein the trigger is activated by the first finger, the vertical bulk of the drive mechanism 5 is reduced, due to the position of the trigger T on the side of the firearm 1 .
In the example shown in FIGS. 1-3 , the aiming distance d 1 is equal to the strong-grasp distance d 2 and is equal to 20 mm; the aiming distance d 1 of the traditional gun 1 ′ shown in FIG. 1 , having the same caliber, is equal to about 33 mm, the distance d 2 of the gun 1 ′ is equal to 55-65 mm.
As evident, the gun 1 according to the present invention is less affected by the recoil phenomenon.
FIGS. 5 and 6 are right and left perspective views, respectively, of the drive mechanism 5 of the gun 1 , which is substantially within the firearm (except for the radially projecting trigger T), and of the firing pin 6 .
FIG. 7 is an exploded view of the drive mechanism 5 and the firing pin 6 .
Referring to FIGS. 5-7 , the firing pin 6 is translatable in a corresponding seat along the X axis, towards the bullet loaded in the barrel 2 or in the breech, if it is present. As the trigger T is pressed, a preloaded spring 7 pushes the firing pin 6 . The drive mechanism 5 comprises, in addition to the trigger T, a drive shaft 8 fixed to the trigger T itself and rotating on the communal rotation axis Y. A thrust cam 9 is keyed to the drive shaft 8 and is shaped so as to transmit a predetermined law of motion to a main lever 10 . The main lever 10 is pivoted at 11 to the main body B of the gun 1 (shown in FIG. 7 ). The opposite end of the main lever 10 is pivoted to a thrust lever 12 . The thrust lever 12 is pivoted at 12 ′ to a snap lever 13 , the latter being in its turn pivoted to the main body B of the gun 1 .
The snap lever 13 is provided with a prominence 14 shaped so as to ensure the shape coupling with a foot 6 ′ of the firing pin 6 and holds it against the thrust of the spring 7 when the snap lever 13 is in a first angular position, corresponding to the firearm 1 at rest.
The rotation of the assembly formed by the trigger T, the drive shaft 8 and the thrust cam 9 on the Y axis, causes the main lever 10 to rotate in the opposite direction on the pin 11 . The thrust lever 12 is pushed backwards and slightly rotated on the pin 12 ′ thus leading to a corresponding rotation of the snap lever 13 up to cause the disengagement thereof from the foot 6 ′ of the firing pin, which therefore snaps forward to activate the bullet primer.
A plurality of springs 15 are provided in order to return the drive mechanism to its initial position after a shot and to be able to operate a new shot.
The operating sequence of the drive mechanism 5 is shown in FIGS. 8A to 12C .
FIG. 8A and FIG. 8C are schematic right and left elevation views of the drive mechanism 5 and the firing pin 6 . FIG. 8B is an enlargement of the encircled portion in FIG. 8C . These figures show the drive mechanism 5 at rest, before the user activates the trigger T. The prominence 14 of the snap lever 13 holds the firing pin 6 thus remaining stationary.
FIG. 9A and FIG. 9C are schematic right and left elevation views of the drive mechanism 5 and the firing pin 6 , and show an instant following that respectively shown in FIGS. 8A and 8C . FIG. 9B is an enlargement of the encircled portion in FIG. 9C . These figures show the drive mechanism 5 when the user begins to press the trigger T in order to rotate it on the Y axis. The above described kinematic chain formed by the elements 8 - 13 leads to the rotation of the snap lever 13 on the pin 13 ′ and to the lowering of the prominence 14 . In FIGS. 9A-9C the prominence 14 has lowered and is at the limit point where the foot 6 ′ is about to disengage.
FIG. 10A and FIG. 10C are schematic right and left elevation views of the drive mechanism 5 and the firing pin 6 , and show an instant following that respectively shown in FIGS. 9A and 9C . FIG. 10B is an enlargement of the encircled portion in FIG. 10C . These figures show the drive mechanism 5 when the snap lever 13 has further lowered up to disengage the prominence 14 from the foot 6 ′ of firing pin 6 . The latter is suddenly pushed forward by the spring 7 . FIG. 10C shows in dotted line the position of the firing pin 6 when disengaging from the snap lever 13 and it can be clearly seen that the experienced forward displacement leads the tip 6 ″ to activate the bullet primer (not shown).
FIGS. 11A and 11C are schematic right and left elevation views of the drive mechanism 5 and the firing pin 6 , and show an instant following that respectively shown in FIGS. 10A and 10C . FIG. 11B is an enlargement of the encircled portion in FIG. 11C . After the bullet primer has been activated, it is discharged from the barrel 2 of the gun 1 and the firing pin is then quickly pushed backward; the foot 6 ′ moves back also with respect to the prominence 14 of the snap lever. A spring 15 slightly raises the thrust lever 12 just enough to release the pin 12 ′ from the corresponding seat 13 ″ obtained in the snap lever 13 and cause the prominence 14 to be raised in order to allows the latter to intercept the foot 6 ′ of the firing pin returned by the spring 7 .
FIGS. 12A and 12C are schematic right and left elevation views of the drive mechanism 5 and the firing pin 6 , and show an instant following that respectively shown in FIGS. 11A and 11C . FIG. 12B is an enlargement of the encircled portion in FIG. 12C . The firing pin 6 is returned to its initial position (corresponding to that shown in FIGS. 8A-8C ) and is ready to be activated again, or to fire again. The drive mechanism 5 is also returned to the initial position.
FIG. 13 is a partial and vertical sectional view of a safety mechanism 16 preventing the snap lever 13 , and thus the trigger T, from rotating if the firearm 1 is not correctly grasped by the user. The safety mechanism 16 is housed in the butt 3 of the firearm and comprises a lever 17 pivoted at 17 ″. A cover 18 ( FIGS. 2, 4 and 13 ) of the lever 17 protrudes backward from the butt 3 towards the user. A spring 19 counters the rotation of the lever 17 . The upper end 20 of the lever 17 has a gripper shape in order to engage the snap lever 13 and prevent it from rotating. When the firearm is correctly grasped, the hand palm causes the rotation of the lever 17 , clockwise in FIG. 13 , leading the end 20 to disengage from the lever 13 which is free to operate, as previously described, to obtain a shot.
FIGS. 14 and 15 are schematic views, respectively a vertical section view and a plan view, of a preferably present second safety mechanism 20 . Such mechanism comprises a button 21 (also shown in FIGS. 2 and 3 ) which protrudes frontally from the butt 3 of the gun 1 to be pressed by the first finger. The button 21 comprises seats 22 for receiving a portion of the trigger T, whereby the rotation of the trigger T is possible only when the button 21 is held down by the user and the seats 22 are aligned with the aforesaid portion of the trigger T.
FIG. 16 shows a rifle 100 according to the present invention, provided with a barrel 102 , a butt 103 , a side trigger T and a safety button 21 which is the same as the one above described relative to the gun 1 .
FIG. 17 is a partial sectional view of the drive mechanism 105 and the firing pin 6 of the rifle 100 . FIG. 18 is an exploded view of the mechanism 105 . The trigger T causes the snap lever 113 snapping, thereby releasing a spring-loaded hammer 106 ; the hammer 106 rotates on its pin 106 ′ and hits against the firing pin 6 .
FIGS. 19-21 refers to another type of rifle 200 according to the present invention, provided with the barrel 202 , the trigger T on the firearm side and the butt 203 . The drive mechanism 205 comprises a cam 209 rotating with the drive shaft 208 . The cam causes the snap lever 213 to rotate until the hammer 206 is released and it suddenly rotates due to the preload of a spring until striking the firing pin 6 .
As evident for a field technician, the advantages provided by the present invention can be used both in guns and in rifles.
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A firearm ( 1 ), for example a pistol or a rifle, is described, wherein the drive mechanism ( 5 ) of the firing pin ( 6 ) is controlled by a trigger (T), a key or a button, laterally positioned on the firearm ( 1 ) and operable by the hand thumb. The firearm, with respect to the known art, is characterized by a reduced aiming distance (d 1 ), which is the distance between the index finger (f 1 ) and the longitudinal axis (X) of the barrel ( 2 ). This leads to a reduced recoil.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to financial transaction systems and methodologies, and in particular to a method and system for making payments based on a customer identification.
[0003] 2. Description of the Related Art
[0004] A wide variety of payment methods are available to consumers of goods and services. In addition to currency, consumers are often able to use their credit in making purchases. A common system for making credit purchases involves the use of a credit card provided by a credit card issuer, such as a commercial bank or other financial institution. Non-credit transactions can be handled by debit cards, which utilize funds already deposited by the consumer for payment purposes.
[0005] Many types of payment methodologies are dependent upon customers having relationships with financial institutions such as banks, credit unions, etc. However, a substantial percentage of consumers do not use such conventional financial institutions. These consumers are often referred to as “unbanked” because they do not maintain accounts with such institution's. Unbanked consumers are often inconvenienced in making financial transactions. For example, without bank accounts, they experience difficulty and inconvenience in obtaining negotiable instruments, making purchases on credit, etc.
[0006] Recently there have been a number of new products which provide at least partial solutions to the problems of the unbanked and other consumers. For example, “prepay” cards allow consumers to pre-purchase various goods and services. An important example relates to the use of telecommunications services, which are available through prepaid “calling cards”. Many consumers prepay on a monthly basis for “dial tone” service. Prepaid cards can also be reloadable whereby additional value can be added by consumers for using their cards indefinitely.
[0007] Another prior art payment system involves the use of payment service providers making payments on behalf of consumers over the Internet global computer network or by negotiable instrument. Such a payment service is available from Western Union Commercial Services under its trademark QUICK COLLECT®. This product allows consumers to make payments to Western Union agents who then transfer funds either over the Internet global computer network or issue negotiable instruments to the payees on behalf of the customers/payors. The customers submit certain identifying information each time they use this service.
[0008] The present invention addresses the need for a payment service method and system which allow customers to gain access to the service simply by providing an identifier. For example, the payment service provider can issue the customers cards adapted for swiping to input their identifiers. A payment service is also needed which substantially instantaneously credits payments to accounts as directed by the customer. For example, customers who purchase prepaid “dial tone” telecommunications services often intend to use such services immediately.
[0009] There is also a need for a payment service provider to retain customer information to facilitate making a payment by simply swiping a card to input the customer's ID and designating a payment amount. Enrolled customers can thus remain in the system's database indefinitly for use of the payment service on demand.
[0010] Heretofore there has not been available a payment service method and system with the advantages and features of the present invention.
SUMMARY OF THE INVENTION
[0011] In the practice of the present invention a payment service provider contracts with its clients to facilitate payments and prepayments on account from their customers. The customers enroll in the service by communicating with the payment service provider through any one of a number of different interfaces. A unique identifier is assigned to each customer and can consist of any suitable character string or similar unique identifier. For example, customers using the payment service for their telephone bills can utilize their telephone numbers as their identifiers. Commercial clients can pre-enroll their entire customer databases with the payment service provider. The payment service provider then simply issues the identifiers and processes applications for enrollment from customers. The payment service provider, or its agents, receive payments from the customers and process same for payment to the clients. The invention accommodates a variety of options and enhancements for customizing and expanding the service.
OBJECTS AND ADVANTAGES OF THE INVENTION
[0012] The principle objects and advantages of the present invention include:
[0013] 1. providing a payment method and system;
[0014] 2. providing such a payment method and system which utilize a payment service provider with an agent network;
[0015] 3. providing such a payment method and system which facilitate payment to clients from the clients' customers;
[0016] 4. providing such a payment method and system which enables customers to contact and enroll in same through a variety of different interfaces;
[0017] 5. providing such a payment method and system which facilitate promoting the use of the payment system and method;
[0018] 6. providing such a payment method and system which promote the products of the payment service provider's clients;
[0019] 7. providing such a payment method and system which are adapted for promoting and cross selling other products of the payment service provider and its clients;
[0020] 8. providing such a payment method and system which capture transactional data for use in managing a customer database; and
[0021] 9. providing such a payment method and system which are efficient in operation and well adapted for the proposed uses thereof
[0022] Other objects 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.
[0023] 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
[0024] FIG. 1 is a block diagram of a payment service system embodying the present invention.
[0025] FIG. 2 is a flow chart for payments made in accordance with the method of the present invention.
[0026] FIG. 3 is a flow chart for enrolling customers.
[0027] FIG. 4 is a flow chart for implementing payment parameters.
[0028] FIG. 5 is a flow chart for a dynamic client/customer interface.
[0029] FIG. 6 is a flow chart for providing advertising and coupons on receipts for payments.
[0030] FIG. 7 is a flow chart for providing an automatic repeat customer discount.
[0031] FIG. 8 is a flow chart for cross selling services of the client.
[0032] FIG. 9 is a flow chart for metering transactions involving accounts.
[0033] FIG. 10 is a flow chart for providing rebates to clients.
[0034] FIG. 11 is a flow chart for alternative payment methods.
[0035] FIG. 12 is a flow chart for additional product support.
[0036] FIG. 13 is a flow chart for client-specific enrollment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.
[0038] Referring the drawings in more detail, the reference numeral 2 generally designates a payment system embodying the present invention. As shown in the block diagram FIG. 1 , the system 2 includes a payment service provider 4 for facilitating payment from a customer/payor 6 to one or more clients/payees 8 .
[0039] Each customer/payor has a unique ID 10 , which can comprise any suitable identifier. Conventional identifiers such as name, social security number, PIN, etc. are acceptable. Moreover, the system 2 can accommodate “anonymous” customers/payors 6 . Such customers 6 can maintain their anonymity by creating their own ID's 10 . The ID 10 can also comprise the customer's telephone number. Thus, the system 2 can be used for paying for telephone services using only the customer's telephone number for identification purposes. The customer in this model does not even have to provide an address or any other personal information. Similar identification arrangements could be used with other clients 8 , i.e. accepting payments on accounts with the customers identified by their respective account numbers. The customer 6 interfaces with the payment service provider 4 through an interface 12 . The interface 12 can comprise any suitable form or device for communications, including telephone (which can incorporate voice recognition (VR)), worldwide web (Internet), mail, in-person, a point-of-sale (POS) terminal with a card reader, e-mail or any other suitable interface.
[0040] The payment service provider 4 can include an agent network 14 which can provide point-of-sale (POS) contact points system-wide for convenient in-person accessibility by the customers 6 . The payment service provider 4 maintains customer accounts 16 which can correspond to the clients/payees 8 . Each client/payee can have associated therewith a customer database 18 containing pertinent information regarding the customers 6 and their respective accounts 17 . The designation of accounts, subaccounts, master accounts, etc. can vary from client-to-client. Thus, as used herein the terms “account”, “subaccount” and similar terms can designate either the entire account base of a particular client 8 , or the individual account of a customer(s) 6 .
[0041] FIG. 2 is a payment flow chart depicting a payment method which commences with the enrollment of a new customer/payor at 22 whereafter an ID 10 is assigned at 24 . An account 17 is established with the payment service provider 4 at 26 . Optionally a card 20 can be issued to the customer 6 at 27 . The card 20 can comprise an ID card, a reloadable/stored value card, a credit card, a debit card, etc. Any suitable card configuration can be utilized. For example, preprinted cards with concealed customer ID's 10 can be inventoried with the agent network 14 for distribution upon enrollment. However, the system 2 can function without any cards whatsoever simply by assigning unique customer ID's 10 for purposes of conducting all payment transactions. A payment is made on the account at 28 . The payment is applied at 30 and the subaccount records are updated at 32 . A decision is made at a decision box 34 if another transaction is to be conducted. If so, the process returns to the payment application step 30 whereby the customer's payment can be applied to another account. If not, the process ends.
[0042] FIG. 3 shows a method of enrolling the customer base of a client 8 including the step of the client creating a customer database at 38 . At 40 the database is formatted, preferably pursuant to the standards established by the payment service provider 4 to facilitate automation of the payment process. All of the customers 6 in the client's customer database can automatically be enrolled in the payment service at 42 . The customers 6 can be notified of the payment service availability at 44 , whereupon the new customer can contact the payment service provider 4 at 46 and activate the account at 48 . The customer ID 10 is assigned at 50 , the customer makes a payment on a client's account at 52 and the client's records are updated at 54 .
[0043] FIG. 4 shows a methodology for establishing payment parameters. At 58 the client designates the products for payment service. The system and method can accommodate clients with multiple products by allowing flexibility in establishing the payment parameters for each and by accommodating different payment directions from customers 6 on the various products. The client designates its payment denominations (e.g. $5, $10, $20, etc. increments) at 60 and applies the payment denominations to its products at 62 . The payment service plan can optionally be configured to accept exact payments of any amount without applying predetermined payment denominations. Payment service provider fees are established at 64 . The fees can reflect the nature of the clients' accounts. For example, payment bands can be input at 66 wherein various bands are applicable according to the number of customers. Pricing can also be based on the ranges of principle payment amounts at 68 . The fees associated with the transactions are input at 70 . The payment service provider 4 can set a variable fee schedule, taking into account factors such as pricing, principle and fee bands and ranges at 72 .
[0044] FIG. 5 shows a dynamic client/customer interface methodology wherein the customer enrolls with the payment service provider at 76 , makes a payment at 78 and is issued a receipt at 80 . The customer is assigned an ID at 82 . Client messaging to the customer is communicated at 83 and can include the customer service number. The value of the available payment service is designated at 84 . A coupon is printed at 85 for eligible customers 6 . Customer eligibility is determined at 86 and ineligible customers are excluded at 88 .
[0045] FIG. 6 shows an optional methodology for utilizing the customers' receipts for advertising and coupons. A client promotion is initiated at 94 . Alternatively, a promotion can be initiated for a non-competitor of the client at 96 . At 98 the advertising or coupons are printed on the receipts, which are provided to the customers at 100 . The customers 6 can redeem the coupons at 102 . At 104 the advertisement and coupon impressions are tabulated for each client and the coupon redemptions are tabulated at 106 . The client pays the payment service provider at 108 . Based on tabulated redemptions, the client can also pay the payment service provider at 110 . Customer data is collected from the coupon redemptions at 111 . The customer data can be manipulated in various ways and reported to the client at 112 .
[0046] FIG. 7 shows a procedure for rewarding repeat customers with discounts. At 116 the interval for the discounted payment service is set and a number of repeat transactions N is set at 118 in order to qualify for a discount. A customer payment count (CPC) is set to zero at 120 . A customer payment is made at 122 and increments the customer payment count (CPC+1) at 123 . At a decision box 124 the customer payment count is compared to the number of payments required for discount eligibility (CPC=N?). If negative, the procedure returns to the customer payment step 122 . If affirmative, an immediate discount can be provided on the current payment charge to the customer at 126 . A congratulatory message to the customer is printed at 128 , for example on the receipt.
[0047] FIG. 8 shows a cross-selling methodology which commences with the step of a new customer enrollment at 130 . A new customer screen is displayed at 132 for purposes of promoting other services of the payment service provider at 134 . For example, other related money-transfer services of the payment service provider 4 can be promoted to the customer 6 at 136 . Internet-based services can be promoted at 138 and direct telephone contact services can be promoted at 140 . The enrollment information can be captured at 142 , and can reflect the services utilized by the customer. Still other services can be promoted at 144 .
[0048] FIG. 9 shows a transaction metering procedure which commences with the client 8 providing the card configuration at 148 . An ID “trap” occurs at 150 whereby a first or other special transaction is identified for special handling. An account transaction counter is initiated at 152 and a first transaction is logged at 154 . A last transaction is logged at 156 and a running log of time elapsed since the last transaction (corresponding to an inactivity period) is maintained at 158 . At decision box 160 a determination is made if the inactivity period has exceeded the maximum allowable period. If affirmative, a retire account step occurs at 162 and the sub-routine ends. If negative, the sub-routine continues to track transaction recurrences at 164 and monitors retentions at 166 . Future marketing and rebate programs are metered at 168 and market records are provided to the client at 170 based upon the data received in the above steps. The market records can be used as an adjunct to the client's customer database.
[0049] FIG. 10 shows a client rebate routine wherein a number of transactions required for rebate eligibility is set with the client at 174 (NTR). New customers are enrolled at 176 , cards are printed at 178 and the clients 8 are charged at 180 . The number of transactions (NT) is initialized to zero at 182 , a transaction occurs at 184 and increments the number of transactions (NT+1) at 186 . At decision box 188 a determination is made if NT=NTR? If affirmative, the cost of the card is rebated to the client at 190 . If negative, the routine returns to the transaction step for the next increment.
[0050] FIG. 11 shows a methodology for making payments using various options. The customer initiates a payment at 194 and provides his or her ID at 196 . Various payment options are displayed, and can include negotiable instruments (e.g. checks, cashier checks, money orders, etc.), credit cards, debit cards, etc. A payment method is selected at 200 and is verified at 202 to ensure that “good” (i.e., collectable) funds are available from the customer 6 utilizing the selected payment method. The payment is accepted at 204 .
[0051] An additional product support procedure is shown in FIG. 12 and commences with the client 8 identifying multiple products to be supported at 208 . For example, a telecommunications client might provide various products such as prepaid dialtone, prepaid cellular, prepaid internet access and insurance. All of these products can be provided on a single card. A premium fee can be charged by the payment service provider 4 at 210 . Destination codes can be assigned to the client's various products and a preferred customer screen created for displaying same at 212 , 214 respectively. The client's products can be displayed on the preferred customer screen at 216 whereby the customer can choose a product to pay on at 218 . At 220 the customer chooses the amount to pay on the chosen product. At decision box 222 the customer has the option of choosing another product to pay on. If affirmative, the preferred customer screen with the multiple products is displayed again. Otherwise, the sub-routine ends.
[0052] FIG. 13 shows a client-specific enrollment methodology, as contrasted with a generic enrollment procedure commencing with client-specific payment service advertising which identifies the payment service provider 4 and directs potential customers to its agent network 14 . The payment service provider agent enrolls a customer on behalf of the client at 226 . The customer is typically either a present or prospective customer for the client's goods or services and has been directed to the payment service provider's agent network 14 as a way of paying for same. At 228 the customer and the payment service provider agent select the features and pricing desired by the customer for the client's products. An account number can optionally be assigned on behalf of the client by the payment service provider agent at 230 . The payment service provider is paid by the customer at 232 , and in turn pays the agent at 234 .
[0053] It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangements of steps and components described and shown.
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A payment service method and system involve a payment service provider, a customer/payor and a client/payee. The customer/payor enrolls in the service and is provided the unique identifier which enables him or her to conduct all transactions with the payment service provider. The customer/payor interfaces with the payment service provider through various forms of communication, and can facilitate payments to the clients/payees through the payment service provider while remaining anonymous. Various enhancements are provided for promoting the services of the clients and the payment service provider to customer bases obtained from persons enrolled in the payment service and from persons who are customers of the clients.
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CONTRACTUAL ORIGIN OF THE INVENTION
The United States Government has rights in this invention pursuant to Contract No. EG-77-C-01-4042 between the U.S. Department of Energy and the Midwest Research Institute.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to solar collectors, and more particularly to a tensioning device for a stretched membrane collector.
2. Description of the Prior Art
Recent developments in the solar collector include a trend toward manufacturing reflectors for concentrating solar collectors with thin flexible lightweight reflector materials. Examples of such lightweight reflector materials are thin metallic sheets of steel or aluminum which are frequently referred to as foils. Collectors manufactured from these materials are commonly referred to as stretched membrane solar collectors. Generally speaking, a solar collector consists of a reflector and a metal-constructed reflector support frame. The reflector is typically in a form of a mirror or plurality of mirror segments.
Individual solar collectors are frequently employed in an array to concentrate solar radiation severalfold by reflecting and focusing the solar radiation onto an absorber/receiver. Solar radiation is commonly known as sunlight and, generally speaking, concerns electromagnetic radiation emitted by the sun. The absorber/receiver which may be of a cavity-type is positioned at the focal area of the array so as to absorb maximum heat energy.
The focal area, broadly speaking, concerns a point or region to which the collector reflects all of the incident sun radiation. The solar energy flux received and absorbed by the receiver/absorber is usually carried away by a suitable heat transfer fluid to either operate a thermodynamic heat engine or to provide process heat. Solar flux generally means energy flux transmitted from the sun, which is in the form of electromagnetic radiation.
The trend toward producing lightweight solar collectors is dictated in part by a high manufacturing cost of mirrored glass/metal-type reflector collectors. This trend is also dictated in part by the heavyweight of mirrored glass/metal-type heliostat reflector panels and their support structures. A heliostat may be simply defined as a tracking mirror. To continue, the reflector panels are typically fabricated from thick heavy metal, glass and composite materials in order to meet strength and rigidity requirements imposed by the heliostat performance. Speaking more specifically, such strength and rigidity is frequently required in order to give the panel the capacity to withstand environmental loads without undergoing warping, buckling or fracturing which eventually could lead to failure, as well as being required to maintain optical accuracy. Examples of such environmental loads are gravity loads, wind loads, and ice/snow loads.
Unfortunately, the heavy deadweight load of the reflector and the reflector suport frame frequently produces stresses and deformations in the heliostat which undesirably add to the harmful stresses produced by environmental loads. Additionally, the use of heavy structural elements and metal materials to add sufficient strength and rigidity so that the heliostats can sustain such loads is one major reason for their high manufacturing cost.
In addressing the disadvantages associated with the heavyweight collectors by producing collectors which employ substantially thinner and lighter weight manufacturing materials, a problem has developed in fabricating lightweight reflector support frames which can safely withstand stresses due primarily to twisting moments normally produced during the tensioning operation. In the tensioning operation, the reflector membrane is typically tensioned to provide a desired reflector surface contour. Unfortunately, however, some of the devices heretofore employed to tension the reflector membrane tension it by loading the reflector support frame substantially eccentrically.
It will be noted that tensioning of the membrane is usually required in order to provide an adequate focal point or image of the sun at the cavity of the absorber/receiver. A tensioned surface reflector will have a focal length which is a function of the reflector elevation angle and surface tension. The characteristics of a tensioned surface with respect to the associated focal point are normally used to enhance collector performance by reducing the size of the image at the receiver and therefore the amount of energy spillover.
Additionally, a problem has developed in providing lightweight stretched collector with variable or adjustable focusing capabilities, such that the collector can be used to produce various concentration ratios to meet specific collector site requirements. Concentration ratios concern the ratio of the intensity of solar light impinging on the absorber to that of the solar light impinging on the collective surface of the collector. Notably, these ratios may be as small as one for no concentration to as high as several thousand.
To cope with the aforesaid problems, the reflector surfaces of some solar collectors have been designed by tensioning a sheet of aluminized Mylar over a plurality of elongated supporting members. The supporting members function to impart a caternary configuration to the aluminized sheet. A prior art patent relating to such a design is U.S. patent Ser. No. 4,173,397. Unfortunately, however, this prior art design as well as others have suffered from one or more shortcomings. For example, this earlier design is unduly complex, comprises a number of component parts, and its focus is not easily controllable.
Some prior art designs have stretched a sheet of aluminized Mylar over the top of a hollow cylinder and reduced the pressure therein between to provide a desired surface configuration. An example of this design is disclosed in U.S. patent Ser. No. 4,288,146. However, unfortunately, this design may result in a proneness to develop leaks, and eventual changes in the pressure within the cylinder leads to undesirable and irreversible degradation of the collector focus. It will be noted that the use of a vacuum pump to maintain the desired pressure has to some degree been partly helpful in reducing some aspects of the problem with pressure leakage. However, a vacuum pump is an additional cost element and is power consuming.
Some prior art designs use flat surface-type collectors. In flat surface-type collectors, the reflected sun radiation is aimed rather than focused at the absorber/receiver cavity. Flat surface-type collectors, however, when employed in applications where high intensity ratios are desired, often produce an unacceptably enlarged focal region at the receiver as a consequence of a spreading of the reflected incident sunlight beam, as well as producing a related unwanted drop in optical efficiency. Optical efficiency generally concerns a measurement of a fraction of the sun energy that actually reaches the absorber/receiver cavity.
SUMMARY OF THE INVENTION
Against the foregoing background, it is a general object of the present invention to provide a tensioning device for a lightweight stretched membrane solar collector which overcomes many of the aforedescribed shortcomings and disadvantages of the prior art lightweight solar collectors.
It is another general object to provide a tensioning device for a lightweight stretched membrane solar collector which in certain embodiments uses only inexpensive readily available materials and components that can be easily and cheaply manufactured.
It is a specific object to provide a tensioning device for a lightweight stretched membrane solar collector which tensions the membrane to a desired configuration while substantially minimizing twisting moments produced by tension forces at the reflector support frame.
It is another specific object to provide a tensioning device for adjustably tensioning lightweight stretched membrane solar collectors.
It is yet another specific object to optimize the collector support frame for minimum weight within design constraints ordinarily required to tension the reflector surface of the collector for most normally anticipated collector applications.
The above objects, as well as still further objects and advantages, are attained by the present invention, which may be described briefly as a solar collector comprising an elastic membrane member for concentrating sunlight, a frame for holding the membrane member in plane and in tension, and a tensioning means for varying the tension of the membrane member. The tensioning means is disposed at the frame and is adapted to releasably attach the membrane member thereto. The tensioning means uniformly and symmetrically subjects the membrane member to stretching forces such that membrane stresses produced thereby are distributed uniformly over a thickness of the membrane member and reciprocal twisting moments are substantially prevented from acting about the frame.
Additional objects, advantages, and novel features of the present invention will be set forth in part in the detailed description which follows, and in part will become apparent to those skilled in the art upon examination of the following description or upon practicing the invention. The objects and advantages of the invention may be realized and obtained by means of elements and a combination of elements particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and form a part of the specification illustrates preferred embodiments of the present invention and together with the description serve to explain the principles of the invention. In the drawings:
FIG. 1 is a perspective view of a lightweight stretched membrane solar collector employing a tensioning device that is constructed in accordance with principles of the invention.
FIG. 2 is an enlarged, cross-sectional, perspective view illustrating the details of the tensioning device and reflector support frame of the lightweight stretched membrane solar collector of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, there is illustrated a lightweight stretched membrane solar collector 2 employing a tensioning device that is constructed in accordance with the invention. The tensioning device is generally denoted by the reference character 4. Generally speaking, collector 2, and thus tensioning device 4, may be employed in numerous applications where a reflector or collector surface is required to retrieve power from solar energy. An example of one such application is a central receiver system which, generally speaking, employs a field of collectors to concentrate solar radiation into an absorber/receiver to generate fairly large amounts of electrical power. Collector 2 generally includes a stretched composite membrane member 6, a membrane support frame 8, and tensioning device 4.
In the present instance, the composite membrane member 6 generally functions to provide tension in the collector surface 5. The membrane member 6 is suspended from the frame 8 through the tensioning device 4 such that the membrane 6 is planar, as well as being held in tension which will be more fully discussed hereinafter. The composite membrane member 6 includes an upper layer or film of a reflector material which serves as the collector surface 5 and a lower layer 7 of metal material which serves as a substrate for the reflector material.
The lower layer 7 may be formed from any number of fairly thin lightweight elastic reflector materials, such as for example, aluminum, steel foils or polymeric foils. The reflector surface 5 may also be formed from any number of well-known plastics which are capable of meeting the mechanical property requirements and optical performance requirements for satisfactory reflector surface operations. Aluminized polyesters and silvered polycarbonates are examples of such reflector surface materials. The reflector surface 5 can also be applied to the lower layer 7 with any number of well-known reflector surface forming techniques. Examples of such techniques are direct metallization techniques, mold-in-films techniques or surface sheet lamination techniques.
The frame 8 generally functions to support the membrane member 6, as well as to hold it in plane and in tension, as previously mentioned hereinbefore. It will be noted that the frame 8 is, in turn, connected to and supported by a pedestal 9. However, the details of the pedestal 9 and the connection of the pedestal 9 to the frame 8 are not fully described herein since they form no part of the present invention and they are well known in the collector art.
To continue, frame 8 is provided with a generally annular shape and is fabricated from a metal material, such as for example, structural steel or aluminum. The frame 8 also includes a circumferentially extending planar portion 10 which defines opposed inner and outer facing surfaces 12, 14.
The planar portion 10 is provided with a pair of transversely spaced circumferentially extending tongue members 16. Each one of the two tongue members 16 generally includes three segments. The first segment extends perpendicularly from the inner surface 12 of the planar portion 10 so as to project radially inward towards a central region 17 of the membrane member 6. The second segment is formed integrally with the first segment and extends therefrom so as to project in an axial direction. The third segment is integrally formed with the second segment and extends therefrom so as to project generally radially outwards away from the central region 17. Together the three segments, and thus tongue 16 define a circumferentially extending excess 18, and are clearly shown in FIG. 1.
Referring now to the tensioning device 4, the tensioning device 4 generally functions to couple the membrane 6 to the frame 8, as well as to provide a means for varying the tension of the membrane 6. The tensioning device 4 includes a radially movable piston 20, and an expander member 22.
The expander member 22 generally functions to impart intermittent radially outward movement of the piston 20 relative to the frame 8. The expander member 8, in the present instance, consists of a pair of inflatable watertight and airtight tubular-shaped bladders. The expander/bladder members 22 may be formed from any material suitable for holding air or liquid under pressure, such as for example a rubber material. Each expander/bladder member 22 is disposed within a corresponding one of the two recesses 18, such that a first portion thereof is in abutting engagement with the inside surface 12 of the tongue 16 and an inner surface 24 of the piston 20.
Referring now to the piston 20, the piston 20 is adapted to seat within the two recesses 18. It is noted that the piston 20 inclues a plurality of circumferentially extending segments 21. The segments 21 are formed in a manner to provide the piston 20 with a ring-type shape when the piston is seated within the recesses 18. The segments 21 function to allow the component members of the membrane member 6, and thus the membrane member 6 itself, to be effectively loaded in a radial direction, as will be more apparent hereinafter. Incidentally, it will be appreciated that a solid circular-type piston, in sharp contrast to the circular segmented piston 20 of the present invention, would support an applied radial load by circumferential loading in the solid piston itself, rather than primarily radially loading the membrane member 6 as is accomplished with the circular segmented piston 20.
To accomplish seating the piston 20 within the recesses 18, the piston 20 is provided with a first circumferentially extending planar or platen portion 26 having inner and outer opposed surfaces 24, 26. The piston 20 is seated within the recess 18 such that the outer platen surface 26 is adjacent the inner surface 12 of the planar portion 10 of the frame 8. The piston 20 is also provided with a circumferentially extending slide portion 28 which generally functions to releasably couple the membrane member 6 to the frame 8 and to assist the piston 20 in accomplishing radial movement.
The slide 28 extends generally perpendicularly from the inner plate surface 24 and projects in a radially inward direction so as to provide the piston 20 with a t-shaped configuration. By this t-shaped configuration, the slide 28 is positioned between the two radially circumferential passages 18, as is clearly shown in FIG. 2.
The slide 28 also includes axially facing opposed surfaces which define a segmented indexing means 32. The indexing means 32 extends rapidly inwardly and generally functions to assist in allowing the slide 28, and thus the piston 20, to intermittently move radially outward in a direction away from the central region 17 of the membrane member 6 in response to expansion of the expander 22, as will be more fully explained hereinafter.
The indexing means 32 in this instance consists of two pluralities of circumferentially extending teeth members, a different plurality of teeth members being disposed at each one of the two opposed side surfaces of the slide 28, as is clearly shown in FIG. 2. Each tooth of the indexing means 32 is evenly spaced in a radial direction from one another and projects generally vertically from the side of the slide 28 that it is associated with. Each one of the two plurality of teeth members is positioned so as to be in abutting engagement with a corresponding circumferentially extending peripheral edge or end portion 30 of the tongue 16.
Each tooth is further adopted to allow the expander 22 to give intermittent radially outward movement to the slide 28, and thus to the piston 20 relative to frame 8, by means of the edge portions 30 sequentially slidably engaging the teeth of the indexing means 32 in response to expansion of the expander bladder members 22. To facilitate the sliding movement of slide 28, each tooth is provided with a sloping ramp-like configuration, as is clearly shown in FIG. 2 and as will be more fully explained hereinbelow. Incidentally, it will be understood that the opposed side surfaces of the slide indexing means 28 are not limited to a construction with teeth, and may be fabricated with other suitable structures for adequately enabling the piston 20 to move intermittently radially outward, such as for example a knurled construction.
An inner facing outer edge portion of the slide 28 is employed to connect a boundary portion 33 of the membrane member 6 thereto, and thus to also connect the membrane member 6 to the frame 8, through a plurality of circumferentially evenly spaced conventional fasteners. Such fasteners may be in the form of nuts and bolts. The fasteners and the associated apertures thereof are both generally denoted by the reference character 34.
In assembling the collector 2, the membrane member 6 is initially coupled to the frame 8 through the slide 28 by way of the fasteners 34 such that the membrane member 6 is held in plane. Thereafter, the membrane member 6 is uniformly and symmetrically stretched to provide the reflector surface 5 with a desired tension through the tensioning device 4.
To accomplish stretching the membrane member 6, the expander bladder members 22 are pressurized via the valves 36 thereof from a first diameter to a second larger diameter. As the bladders 22 expand, the inside surface 12 of the tongue 16 and the inside surface 24 of the piston 20 in contact therewith are subjected to the tension forces produced by the expanding bladders 22. In response to such expanding, the piston 20 is induced to move radially outwards relative to the frame 8 and is given intermittent movement by means of the tongues 16 engaging the teeth of the indexing means 32. As the slide 28 moves radially outward, each tongue 16 slides over the teeth thereof 32 in a manner to sequentially lockingly engage one tooth 32 at a time, and thereby index the radial movement of the piston 20. At the end of each indexing movement, the position of the slide 28 and thus the piston 20 is releasably locked by the teeth 32 so as to allow incremental and adjustable tensioning of the membrane 6, as will become more fully discussed hereinbelow.
Additionally, as the piston 20 is caused to move intermittently radially outward, the membrane 6 is submitted to the action of stretching forces applied at the boundary 33 thereof. Such stretching are forces parallel to a plane of the membrane 6 and are distributed uniformly over a thickness T thereof such that a stress distribution produced thereby is essentially solely plane. It is contemplated that the magnitudes of the tension induced in the membrane member 6 is in a range of from about 13,000 n/m (75 lb/in) to about 26,000 n/m (150 lb/in).
As a consequence of uniformly subjecting the piston 20 and the tongue 16 to the action of tension forces produced at the expander bladders 22, and as a consequence of holding the membrane 6 such that the stress distribution therein is plane, twisting moments that heretofore would act about the frame 8 during tensioning of the membrane 6 are substantially minimized. Because of the minimization of the twisting forces, it is contemplated that the frame 8 may be made with substantially thinner manufacturing material than heretofore used in the frame manufacture. It is further contemplated that these thinner frames will not be prone to fail when the membrane member 6 is under tension loading as predicted by skilled persons with the thicker prior art frames. For example, the thickness T of the frame 6 for all normally anticipated collector applications is in a range of from about 1 mm (0.040 in.) to 2 mm (0.080 in.).
It will be understood that the tensioning means 4 is also adapted to release or to adjust the tension in the membrane member 6 and thereby enable the focal length associated therewith to be controllable. To accomplish releasing the tension in the membrane 6, the pressure in the bladders 22 must be released while it is still seated within the recess 18, and the tongue 16 must be disengaged from the teeth 32. The pressure may be released through the valves 36. The tongues 16 may be disengaged from the teeth 32 by prying them in a radial direction towards the center 17 of the membrane member 6 such that the piston 20 is unlocked and is freely movable to a desired position.
In view of the aforesaid, it will now be appreciated that the collector 2 of the present invention has several advantages over earlier stretched membrane types in that: in collector manufacturing, the frame of the collector may be optimized from minimum weight within the desired design constraints regarding tensioning of the reflector surface because of the minimization of the twisting moments associated with tension loading; and the tensioning means enables the tension in the membrane member 6 to be adjustably varied, thereby providing collector 2 with the capability of having its focus or aimpoint adjusted to meet specific collector site requirements. The aimpoint of a collector concerns the target area to which the incident sun radiation is reflected.
The foregoing description of the preferred embodiments of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. For example, a liner 38 may be disposed between each one of the two bladders 22 and the piston 20 to protect the bladders 22 from getting pinched or fractured by the teeth of the indexing means 32. Such a liner 38 could be formed from any number of plastic materials suitable for protecting bladder-type members, like for example, nylon webbing or vinyl plastics.
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 operations shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claims.
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Disclosed is a solar concentrating collector comprising an elastic membrane member for concentrating sunlight, a frame for holding the membrane member in plane and in tension, and a tensioning means for varying the tension of the membrane member. The tensioning means is disposed at the frame and is adapted to releasably attach the membrane member thereto. The tensioning means is also adapted to uniformly and symmetrically subject the membrane member to stretching forces such that membrane stresses produced thereby are distributed uniformly over a thickness of the membrane member and reciprocal twisting moments are substantially prevented from acting about said frame.
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CLAIM OF PRIORITY
This patent application makes reference to, claims priority to and claims benefit from U.S. Provisional Patent Application Ser. No. 61/966,518 filed on 25 Feb. 2014. The above stated application is hereby incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
The present invention provides novel wall construction systems and materials for residential and commercial construction that incorporate grooved lightweight building material units (e.g., blocks, panels, and the like), a plurality of connection devices, a track system, and (injected) polyurethane structural foam. The wall construction system comprises building material units married to a building frame with a plurality of connection devices (e.g., clip fasteners) slidingly retained in a track system that is attached to the building's structural (e.g., load-bearing) framing. The building material units are joined to each other with a suitable binding agent. The cavity between the frame and the building material units is injected with an insulating structural polyurethane foam. The exterior of the wall is finished with a waterproof applied finish such as cementitious stucco. The interior of the wall is amenable to standard finish options.
BACKGROUND OF INVENTION
There are many conventional construction systems used for residential and light commercial building projects which employ sheathing over wood and/or light-gage steel frames combined with insulation and exterior cladding components. Generally, these construction systems, while widely used, are known to have various limitations, including, allowing moisture penetration, thermal bridging, air infiltration, being subject to decay, mold and mildew, infestation, vulnerability to fire, and/or time consuming and labor intensive or expensive construction methods. In addition to the many conventional construction systems noted above other construction techniques use exterior walls composed of concrete or a lightweight concrete variant known as Autoclaved Aerated Concrete (AAC). While existing AAC construction methods can ameliorate some of these limitations seen in conventional building materials and construction methods, the construction field generally still searches for answers to a number of persistent limitations.
For example, U.S. Pat. No. 6,510,667, to Cottier et al. disclose a process for constructing a wall that includes the steps of erecting a rigid frame and attaching fiber reinforced cementitious sheets to the front and rear faces of the frame to form a void there between. This void is then filled with lightweight aggregate concrete slurry and allowed to cure. The lightweight aggregate slurry to fill the void formed between the sheets may be of conventional composition and can incorporate pulverized scrap polystyrene foam material (“grist”) or expanded polystyrene beads. The cementitious sheets may comprise an autoclaved cured reaction product of metakaolin, Portland cement, crystalline siliceous material and water. U.S. Pat. No. 6,532,710, to Terry discloses a solid monolithic concrete insulated wall system comprising 100% concrete construction on interior walls and exterior walls of buildings. Building materials consist of conventional concrete which is poured inside a cavity between two stay in place forming walls completely around the perimeter of the building. A highly cellular, lightweight material from quartzite, lime and water, known as Autoclaved Aerated Concrete (AAC) is used as a “stay in place” forming system of the exterior walls and interior walls. Two AAC walls run the entire perimeter of the respective building. The two walls are designed to form a cavity in which the concrete is poured. Anchor bolts, which are bolted deep into each side of the walls, hang into the cavity. For insulation purposes two sheets of foil backed insulation are attached to the inside of the outside wall by the anchor bolts. U.S. Pat. No. 7,204,060, to Hunt discloses a system for manufacturing structures using AAC. The first step is construction of the wall system, which comprises a first course of elongated AAC base blocks for placement on a pre-built foundation. U.S. Pat. No. 3,943,676, to Ickes discloses a modular building wall unit comprising a hard foam layer and a concrete layer intimately bonded to each other along an interface between the layers. A reinforcing wire mesh matt is embedded in the hard foam layer and reaches with anchoring elements into the concrete layer which may also have embedded therein a further wire mesh matt. U.S. Published Patent Application No. 2008/0016803, to Bathon et al. disclose a wood concrete composite system that comprises a wood construction component, an intermediate layer and a concrete construction unit. A single intermediate layer consists, for example, of a plastic foil, an impregnated paper, a bitumen pasteboard, a plastic insulating layer, a mineral insulating layer, an organic insulation material, a regenerating insulating material and up-poured and/or applied materials, which tie and/or harden at a later time, e.g., tar, adhesive, plastic mixtures. The range of types of concrete suitable for the concrete construction unit includes aerated concrete. U.S. Published Patent Application No. 2007/0062151, to Smith discloses a composite building panel which includes a frame and a concrete slab made of aerated concrete. Fastened to the frame members is a reinforcing layer. The frame is oriented towards the interior side of the structure and the concrete slab is oriented towards the exterior side of the structure. The exposed frame provides cavities for the installation of plumbing, electrical wiring and insulation. U.S. Published Patent Application No. 2008/0010920, to Andersen discloses a method of building construction wherein blocks and panels made from autoclaved aerated concrete are used as structural elements, including insulated panels having a rigid polyurethane/polyiscocyanurate foam core, are attached to structural elements via metal anchoring clips. U.S. Published Patent Application No. 2005/0284100, to Ashuah et al. disclose a wall section having a sandwich like structure, which includes an external vertical panel and an internal vertical panel spaced apart in a parallel relationship, further including a vertical insulating layer. The external panel may be constructed of building blocks made of concrete or AAC. The internal panel may be constructed of wood panel. Between the panels there is a space, “core” which includes a vertical layer of concrete. The outer surface of the external panel is covered with a coating layer constructed of materials selected from among a group comprising of stone, marble, mortar, wood, aluminum, glass, porcelain and ceramics. U.S. Published Patent Application No. 2001/0045070, to Hunt, discloses autoclaved aerated concrete panels, and method of making and using such panels, specifically for the construction of residential homes. U.S. Pat. No. 8,240,103, to Riepe, discloses a composite construction system and a method of constructing a wall that incorporates AAC blocks married to a building frame with a plurality of connection devices. The AAC blocks are joined one to the next with thin-bed mortar. The cavity between the frame and the AAC blocks is injected with structural insulating foam such that a layer (or a fill) of foam is formed in place once expanded and cured. And the exterior of the AAC walls are finished with waterproof cementitious stucco finish. Riepe describes a plurality of connection devices having projections (i.e., stubs) that engage grooves in the tops and bottoms of the AAC blocks. Individual connection devices are attached directly and non-slidingly fixed (e.g., with screws) to the exterior surface of the building's framing in level horizontally orientated rows corresponding to the grooves in the tops and bottoms of the AAC blocks. Each member of the building's framing may have from 1, 2, 3, 5, 10, 20, 50, or more, connection devices fixedly attached thereto. The U.S. Pat. No. 8,240,103 patent is incorporated by reference herein in its entirety.
There have been a number of advances in the field of construction materials and construction systems as demonstrated by use of AAC blocks and connection devices described in U.S. Pat. No. 8,240,103 patent. Nevertheless, what is needed are wall construction systems and materials suitable for residential, commercial, and other construction projects that substantially ameliorate at least some of the disadvantages of existing conventional and/or AAC construction techniques such as reducing labor requirements during construction and/or other installation requirements. It is contemplated that labor savings during construction and installation will reduce total costs and allow for greater building efficiencies to be realized.
SUMMARY OF THE INVENTION
The present invention provides novel wall construction systems and materials for residential and commercial construction that incorporate grooved lightweight building material units (e.g., blocks, panels, and the like), a plurality of connection devices, a track system, and (injected) polyurethane structural foam. The wall construction system comprises building material units married to a building frame with a plurality of connection devices (e.g., clip fasteners) slidingly retained in a track system that is attached to the building's structural (e.g., load-bearing) framing. The building material units are joined to each other with a suitable binding agent. The cavity between the frame and the building material units is injected with an insulating structural polyurethane foam. The exterior of the wall is finished with a waterproof applied finish such as cementitious stucco. The interior of the wall is amenable to standard finish options.
In particularly preferred embodiments, the building systems and methods of the present invention incorporate and make use of lightweight building material units comprising units of Autoclaved Aerated Concrete (AAC). AAC does not burn and 4″ of AAC block material has received a 4-hour fire rating. The AAC material units can be in the form of blocks, panels, or any suitable finished dimensional AAC product.
AAC is a structural product composed of a mixture of cement, lime, water, and sand and aluminum powder. To manufacture AAC, cement is mixed, with lime, silica sand, water, and aluminum powder and poured into a mold. Other materials can be added or substituted into the AAC mixture including, but not limited to, pulverized fuel ash. The reaction between aluminum and cement causes microscopic hydrogen bubbles to form, expanding the cement to about five times its original volume to fill a preselected mold. After evaporation of the hydrogen, the aerated concrete is cut to size and steam-cured in an autoclave. The finished products can be cut and machined into precisely dimensioned units and drilled through or grooved as specified. At the construction site, AAC units (e.g., blocks or panels) can be joined with thin-bed mortar.
As an integrated building system, the present invention comprising walls constructed of AAC blocks provide many benefits to residential and commercial buildings, including, but not limited to, providing high thermal resistance, preventing thermal bridging, providing increasing protection against water damage, vapor damage, fire, decay, mold or mildew damage, frost damage and insect damage, being impact resistance, reducing the need for painting or maintenance; the absence of any toxic compounds; providing a greater acoustical barrier and providing stronger shear strength. In addition, the building system is lightweight for transport and construction and compatible with existing plumbing, wiring, roofing, exterior stuccos and interior finishes commonly used.
While in some preferred embodiments the present construction systems are optimized for constructing walls made of AAC blocks, the clip fasteners, track system, and shelf angle components of the present invention are not limited to applicability solely with AAC construction materials. For example, in certain other embodiments, additional and/or substitute lightweight building material units with suitable properties for use with the present invention are specifically contemplated for use in wall construction (e.g., clay honeycomb blocks, bio-composite blocks comprising recycled or sustainable adjunct materials such as hemp, wood chips, fuel fly ash, recycled aggregate and the like). In still further embodiments, concrete blocks with various additives and/or fillers and the like that otherwise have one or more of the desirable properties mentioned of AAC construction materials are contemplated.
The present invention provides certain improvements over existing AAC wall construction systems and components. Notably, recent U.S. Pat. No. 8,240,103 described a composite construction system and a method of constructing walls that incorporates AAC blocks married to a building frame with a plurality of connection device. The U.S. Pat. No. 8,240,103 advanced the state of the construction arts by introducing the fixed clip system described therein. The present invention describes an improvement upon U.S. Pat. No. 8,240,103 by providing a track system that slidingly retains a plurality of connection devices. The systems and methods of the present invention require comparatively less labor and installation time than existing AAC construction systems and provide greater wall assembly flexibility.
In one preferred embodiment, the present invention provides novel building materials and wall construction methods that incorporate a plurality of stacked AAC blocks that are attached to the building's framing (e.g., wood studs, metal studs, concrete, and the like) by a plurality of connection devices (e.g., clip fasteners) which engage one or more grooves in the surface of the blocks. Preferably, the AAC blocks have one or more continuous grooves in either/both their top and bottom surfaces; however, intermittently spaced grooves in either/both of these surfaces are contemplated as well. Grooves in the AAC blocks can be centered or off-centered on a particular surface. In preferred embodiments, a groove on one surface (e.g., the top surface) of an AAC block has a corresponding groove in the same transactional plane on the opposing surface of the block (e.g., the bottom surface). The lightweight building construction units employed in the compositions and methods of the present invention can comprise one or more grooves in 1 to 2 to 3 to 4 to 5 or to 6 surface(s) of a respective unit.
In another embodiment of the invention, the top and bottom grooves of the lightweight building material units (e.g., AAC blocks) comprise a space of about ½″ deep by about ¼″ wide, and more preferably, by about ⅛″ wide.
In a preferred embodiment, the connection devices comprise clip fasteners. A plurality of clip fasteners are slidingly retained in a track system that is horizontally attached to the exterior surface (face) of the building's load-bearing framing (e.g., wood or metals studs and the like). A plurality of tracks are attached to the exterior surface of the building's framing. Track sections are placed end-to-end in succession such that the respective sections form a continuous integrated track of the desired length on the exterior surface of the building's framing (e.g., level relative the building foundation). It should be noted, however, that the wall construction methods comprising the clip fasteners and sections of track system of the present invention are equally applicable to the construction of interior walls where the track sections are additionally, or in substitution thereof, attached to the interior surface of the building's framing.
The tracks are optimized in cross-section to slidingly retain a number of clip fasteners along their length. Once the clip fasteners are positioned in a track section, they are orthogonally disposed between the track and the AAC blocks. The AAC blocks stand off from the building's framing by the combined length of the clip fasteners and tracks system section(s). This forms a first void between the interior surface of the AAC blocks and the exterior surface of the building's framing. A second void is formed on account of the width of the load-bearing building framing members (e.g., dimensional 2″×4″ or 2″×6″ wood studs, and the like, and/or metal studs) as measured from the interior surface of the building framing members to the exterior surface of the members. The first and second voids, respectively, form a cavity that is injected with a structural insulating foam. Successive rows (i.e., courses) of AAC blocks are joined with thin-bed mortar. Successive rows of ACC blocks form a wall surface the exterior of which is preferably covered with a waterproof finish such as cementitious stucco finish. In a preferred embodiment, the bottom row of AAC blocks are grooved on the bottom surface and this groove is engaged by a shelf angle mounted to the base of the wall.
In preferred embodiments, the invention comprises a composite construction system coupling a frame and AAC blocks, the system comprising: a load-bearing frame and at least a single intermediate layer of injected polyurethane foam, an AAC block unit wherein one side of the block faces towards the load-bearing frame (e.g., an interior ACC block surface), and further wherein the at least single intermediate layer of polyurethane foam is interposed between the load-bearing frame and the AAC blocks so as to couple the load-bearing frame and the AAC blocks; and a plurality of connection devices (clip fasteners) slidingly retained on a track between the load-bearing frame and the AAC concrete construction unit.
The construction systems and materials of the present invention are compatible with wood framing, heavy timber framing, steel framing or heavy steel frame with steel stud infill. In one embodiment of the present invention, the load-bearing frame is made out of at least one of a group of materials consisting of solid wood, timber materials, engineered wood products, wood composite materials, steel, aluminum, concrete, plastics and other composites, recycled and sustainable materials, or other suitable materials. In one embodiment of the present invention, the load-bearing frame comprises a material selected from a group consisting of wood and metal. In preferred embodiments, the load-bearing frame is otherwise non-sheathed.
In a further embodiment, each of the plurality of connection devices (e.g., clip fasteners) comprise at least a first end (a first terminus) that is inserted into a track system that is attached to the load-bearing frame and second end (a second terminus) that terminates in at least one attachment surface, and more preferably two attachment surfaces (i.e., interlock stub(s)). The attachment surfaces are optimized for engaging a groove in a lightweight building material unit such as an AAC block. More particularly, in some preferred embodiments, the plurality of connection devices comprises clip fasteners. In preferred embodiments, the first terminus of each respective clip fastener comprises two compressible legs comprising a roughly “Y” shaped cross section. In preferred embodiments, each of the respective leg sections terminate in a hook shaped (e.g., semicircular) element. The ends of the legs thus form a gap (space) in between one another when not being compressed. In one preferred embodiment, the gap when the legs are not being compressed measured at the widest point on the inside surfaces of the leg is from about ⅛″ to about 6″, more preferably from about ¼″ to about 3″, and more preferably from about ¾″ to about 1¼″. In still other embodiments, the gap is about 1″.
In particularly preferred embodiments, the “Y” shaped legs can be compressed by the wall system installer (e.g.; a mason) by simply using finger strength such that the legs are pushed together relative to the gap and the central axis of the clip fastener. Once compressed, the legs of the clip fastener are inserted into the channel of the track section and the compression force is released such that the legs revert back into their approximate pre-compression shape and orientation within the channel of the section of track system thereby creating a slight tension between the legs and the track section. The cross section of the lengths of track section are optimized to slidingly retain the clip fasteners inserted therein. The second terminus of each respective clip fastener comprises a termination having a roughly “T” shaped cross section. The “T” shaped section comprises two projections (i.e., stubs) orientated at right angles relative the main body of the clip fastener. The interlock stubs comprising the T shaped end of the clip fasteners are optimized to engage corresponding grooves in one or more surfaces of the lightweight building material units (e.g., AAC blocks). In a preferred embodiment, the stubs of the clip fastener components comprise protrusions of about ½″ long and about ¼″ wide. It should be noted, however, that different stub protrusion dimensions (and groove dimensions) are possible within common variations in view of the desire to achieve sufficient engagement of the grooves in the lightweight building material units by the clip's stubs.
In a further embodiment, the plurality of connection devices (e.g., clip fasteners) comprise a material selected from a group consisting of suitable metals (e.g., aluminum, steel, and the like), plastics, and composite materials. The connection devices (e.g., clip fasteners) should be constructed from a material, or combination of materials, that provide a sufficient level of elasticity after repeated deformations such that the device is able to return to its original shape. In a preferred embodiment, the clip fasteners are made of plastic, and more preferably, of an ABS plastic, although other materials such as suitable metals and composites as possible.
In preferred embodiments, the track system of the present invention provides a race for receiving and slidingly retaining a plurality of clip fasteners. While not being limited to any particular configuration, preferably the track is roughly “C” shaped in cross section. The main body of the track system preferably has at both top and bottom edges a short protrusion at a right angle therefrom. These top edge and bottom edge protrusions terminate in two opposing inwardly turned bevels/ridges that positively engage a correspondingly shaped hook (e.g., semicircular) element found at the terminus of each of the respective “Y” shaped legs sections at the first end of clip fastener. In some embodiments, the two opposing inwardly turned bevels are semicircular in section. The leg section of the clip fastener when compressed, inserted, and subsequently released, engage the opposing channel bevels at the top and bottom edges of the U shaped track system. Within design variations, any track section cross section and leg section of the clip fastener cross section that provide sufficient tension and slide ability are contemplated.
In certain embodiments, the track sections comprise a material selected from a group consisting of suitable metals (e.g., aluminum, steel, and the like), plastics, and composite materials. The track sections should be constructed from a material, or combination of materials, that provide a sufficient level of elasticity after repeated deformations such that the device is able to return to its original shape.
Individual track sections are not limited to being any particular length. Indeed, the length of respective track sections is directed by manufacturing, transportation and storage, and on site handling and installation considerations. In preferred embodiments, a number of track sections are attached to the exterior surface of the building's load-bearing frame using a plurality of regularly, or irregularly, spaced attachment devices including, but not limited to, one or more screws, bolts, nails, rivets, adhesives, and the like. In instances where the attachment devices traverse the track sections, it is contemplated that track sections are either premade or modified (e.g., drilled, punched, or cut) on site to have a sufficient number of holes to receive the attachment devices. In one embodiment, track sections are secured to the load-bearing framing with a plurality of screws. In particularly preferred embodiments, the screws comprise self-drilling peer-driven screws. In a preferred embodiment, a plurality of track system sections are attached to one or more track support sections (e.g., girts) that are attached in a horizontally disposed (relative to the building's foundation) succession to the exterior surface of the load-bearing framing. The plurality of track support sections can be attached to the exterior surface of the load-bearing framing by any conventional attachment device including, but not limited to, screws, bolts, nails, rivets, adhesives, and the like. In preferred embodiments, the plurality of track support sections are attached with nails. In another preferred embodiment, the plurality of track support sections are attached with screws.
In a further embodiment, the track support sections comprises a material selected from a group consisting of suitable wood, wood composites, metals (e.g., aluminum, steel, and the like), plastics, such as ABS, pultruded fiberglass, and composite materials. In a preferred embodiment, the track support sections comprise wood or wood composites. Wood and wood composites materials suitable for track support sections include, but are not limited to, 1″×3″, 1″×4″, 1″×5″, 1″×6″, 2″×4″, 2″×6″, 2″×8″, 4″×4″, 4″×6″, and the like, as well as dimensional sizes and metric equivalents thereof. The horizontal track support sections are referred to as “girts.”
In still other embodiments, the construction materials, and accompanying construction methods, of the present invention provide and employ one-piece integrated track supports sections (girts) with track system sections. In still other embodiments, the construction materials, and accompanying constructions methods, of present invention provide one or more horizontal track supports sections (girts) attached to one or a plurality of track system sections prior to installation of the track supports onto the load-bearing framing.
In preferred embodiments, the first course of the lightweight building material units (e.g., AAC blocks) installed is engaged by a one or more of a plurality of shelf angles attached to the bottom portion of the load-bearing faming members. In preferred embodiments, the shelf angle comprises a roughly “L” shape cross section such that the shelf angle is defined as a right angle having a vertical leg and horizontal leg wherein the vertical leg is attached to the load-bearing faming and the horizontal leg terminates in a vertical protrusion (e.g., a continuous or discontinuous interlock stub). In another embodiment of the invention, the vertical leg of the shelf angles comprises a wide base that narrows as it extends upwards to form an inclined surface facing away from the load-bearing frame. In particularly preferred embodiments, the stub portion of the shelf angle engage the bottom groove of the lightweight building material units placed on the angle sections. A groove in the bottom surface of each of the first course of AAC blocks in a wall section is engaged by the self-angle.
In a further embodiment, the shelf angles comprise a material selected from a group consisting of suitable metals (e.g., aluminum, steel, and the like), plastics, such as ABS plastic, pultruded fiberglass, and composite materials. In a preferred embodiment, the shelf angles comprise pultruded fiberglass and/or fiber reinforced plastics. In preferred embodiments, a plurality of sections of shelf angle are attached to the exterior surface of the building's load-bearing framing using a plurality of regularly, or irregularly, spaced attachment devices comprising, but not limited to, one or more screws, bolts, nails, rivets, adhesives, and the like. In instances where the attachment devices traverse the shelf angles, it is contemplated that the shelf angles are either premade or modified on site with a sufficient number of holes to receive the attachment devices. In a preferred embodiment, sections of shelf angle are secured to the load-bearing framing with a plurality of screws. In particularly preferred embodiments, the screws comprise self-drilling peer-driven screws.
In another embodiment of the invention, the methods further comprise the step of placing leveling grout into any gaps underneath the shelf angles.
In a still further embodiment of the present invention, the methods further comprise the step of attaching the vertical legs of the plurality of shelf angles to the load-bearing frame preferably in a horizontal orientation; nevertheless, one or more shelf angle sections can also be attached vertically to the load-bearing frame.
Additionally, preferred clip fasteners, sections of track system, and sections of shelf angle, comprise materials exhibiting one or more desirable properties including, but not limited to, having/being sufficiently resistant to chemical degradation, fire resistant, mold, mildew, resistant to insect and rodent damage, high impact resistance, high shear strength, sufficient workability over a wide range of ambient temperatures, minimal to no thermal bridging, and/or being lightweight. The particular dimensions of the track system, clip fasteners, and shelf angles are not critical to successfully deploying the building systems and construction materials so long as the desirable wall properties are achieved in regard to wall strength, rigidity, ductility, thermal insulation, fire resistance, insect, rot, mold, and mildew damage resistance, waterproofing, and the like, in addition to sufficient sliding retention of the clip fasteners by the track system.
In one embodiment of the present invention, the load-bearing frame and the AAC concrete construction are erected on a concrete foundation. The present invention is not limited however to the choice of base or foundation selected for use with the wall construction methods and building material systems, as the present invention can be adapted for use with any standard construction technique (e.g., slab foundations, foundation walls, and the like). In a further embodiment of the present invention, the foundation comprises a concrete foundation. In another embodiment of the invention, the construction methods further comprise the step of anchoring the first plurality of connection devices and/or shelf angle sections to the foundation.
In one embodiment of the invention, the methods further comprise the step of adding an adhesive to the top and/or bottom grooves of the AAC blocks before placing them on the wall. Suitable adhesives include, but are not limited to, thin-bed mortar, and gun-grade adhesives.
In another embodiment of the present invention, the distance between the exterior surface of the load-bearing frame and the inside surface of the AAC concrete construction comprises from about 1″ to about 10″ or more, preferably, from about 1½″ to about 8″, more preferably, from about 1½″ to about 6″, and even more preferably, from about 1½″ to about 4″.
In preferred embodiments of the invention, the cavity created using the lightweight building material units (e.g., AAC blocks), connection devices (e.g., clip fasteners), sections of track system, and sections of shelf angle of the present invention is partially filled with an expanding structural polyurethane foam. In another embodiment of the invention, a single intermediate layer (fill) of polyurethane foam comprises a width of from about 1″ to about 10″, or from about 2″ to about 10″ or more, more preferably, from about 2″ to about 8″, and even more preferably, from about 3½″ to about 6″.
Suitable injectable polyurethane foams comprise polyurethane foams having a water-vapor permeability of about less than one perm, and thermal performance of about R-5 (or more) per inch or more, and/or a total integrated wall system value of about R-40. Suitable polyurethane foams include, but are limited to, closed-cell polyurethane foams having about two-pound density. The present invention is not limited to any particular polyurethane and/or polyurethane structural foams however. Indeed, foams suitable for use with the present invention comprises at least one, and more preferably several, of the following suitable characteristics: impermeability (i.e., from about 100 to about 90 to about 80 to about 70% impermeability) to vapors and water, thermal barrier properties, resistance to/prevention of thermal bridging, acoustic deadening/proofing properties, shock absorbance properties, zero (or acceptably low) outgassing of toxic and/or noxious fumes, fire resistance and, importantly, the requisite adhesive qualities.
In a further embodiment of the invention, an exterior finish can applied to the exterior of the AAC concrete construction. In one embodiment of the invention, the exterior finish comprises a cementitious stucco finish. In still another embodiment, the cementitious stucco finish comprises a waterproof stucco finish modified or otherwise.
In another embodiment of the invention, any standard interior finish can be applied to the interior surface of the load-bearing frame (i.e., the occupied space). In one embodiment of the invention, the interior finish comprises any standard interior wall finishing materials and/or techniques such as dry wall including, but not limited to, drywall, plasterboard, wallboard, gypsum board, plaster, wood and composite wood product paneling, concrete panels, tile, and the like.
The present invention provides many advantages Compared to existing construction systems. In certain embodiments, the compositions and methods of the present invention comprise an improvement to U.S. Pat. No. 8,240,103.
In a composite construction system having: a load-bearing (non-sheathed) frame and a lightweight concrete construction unit, and an internal cavity (of at least 1″ width) between the load-bearing frame and the lightweight construction unit, wherein one side of the lightweight concrete construction unit faces towards the load-bearing (non-sheathed) frame, further wherein the load-bearing (non-sheathed) frame is adhered to the lightweight concrete construction unit using at least a single layer of (injected) polyurethane foam interposed between the load-bearing (non-sheathed) frame and the lightweight concrete completely filling the internal cavity, wherein the layer of polyurethane foam prevents thermal bridging between the load-bearing (non-sheathed) frame and the lightweight concrete; and a plurality connection devices between the load-bearing (non-sheathed) frame and the lightweight concrete construction unit, wherein the improvement comprises the plurality of connection devices slidingly retained in a section of track system.
The invention also comprises a method of constructing a wall, the method comprising the steps of: a) erecting a load-bearing frame having an interior facing surface and an exterior facing surface on a support such as a conventional foundation or slab; b) attaching a first plurality of shelf angle sections (on top of the foundation) on the exterior surface of the load-bearing frame, wherein each of the shelf angle sections comprises an upwardly projecting interlock stub, further wherein each of the shelf angle sections is placed such that the interlock stub extends in an upward direction from the foundation distal from the load-bearing frame; c) placing a first plurality of lightweight building material units (e.g., AAC blocks) on top of the shelf angle sections exterior to the load-bearing frame by inserting the interlock stubs of the placed first plurality shelf angle sections into a bottom groove on each lightweight building material unit, such that a vertical internal cavity is created between the load-bearing frame and the first plurality of lightweight building material units, wherein each lightweight building material unit further comprises a top groove, further wherein the plurality of lightweight building material units have an interior surface facing the load-bearing frame and an opposite exterior surface; d) attaching a first plurality of track support sections on the exterior surface of the exterior surface of the load-bearing frame; e) attaching a first plurality of track system sections to the first plurality of track support sections; f) inserting a first plurality of connection devices (e.g., clip fasteners) into the first plurality of track system sections such that the first plurality of connection devices is slidingly retained in the first plurality of track system sections wherein each of the first plurality of connection devices comprises a downward interlock stub and an upward interlock stub, further wherein each of the first plurality of connection devices is placed such that the downward interlock stub is inserted into the top groove of the first plurality lightweight building material units; g) applying a layer of adhesive (e.g., thin-bed mortar) to the top surface of the first plurality lightweight building material units; h) placing a second plurality of lightweight building units directly on top of the first plurality of lightweight building material units wherein each of the units has a top groove and bottom groove, further wherein the top interlock stub of the first plurality of connection is inserted into the bottom groove of the second plurality of lightweight building material units; i) repeating steps (d) through (h) until the desired exterior wall height is achieved and vertical internal cavity separating the lightweight building material units and the load-bearing frame is achieved; j) applying an exterior finish (e.g., two-coat cementitious stucco) to the exterior surface of the lightweight building material units; k) injecting a polyurethane foam into the vertical internal cavity and allowing said polyurethane foam to expand and cure; and l) applying an interior finish to the interior surface of the load-bearing frame. It is to be understood that the exact order of steps outlined herein may be rearranged or substituted so long as the desired wall is achieved.
The invention also comprises a method of constructing a wall, the method comprising the steps of: a) erecting a load-bearing frame having an interior facing surface and an exterior facing surface on a support such as a conventional foundation or slab; b) attaching a first plurality of shelf angle sections on top of the foundation on the exterior surface of the load-bearing frame, wherein each of the shelf angle sections comprises an upwardly projecting interlock stub, further wherein each of the shelf angle sections is placed such that the interlock stub extends in an upward direction from the foundation distal from the load-bearing frame; c) placing a first plurality of AAC blocks on top of the shelf angle sections exterior to the load-bearing frame by inserting the interlock stubs of the placed first plurality shelf angle sections into a bottom groove on each lightweight building material unit, such that a vertical internal cavity is created between the load-bearing frame and the first plurality of AAC blocks, wherein each lightweight building material unit further comprises a top groove, further wherein the plurality of AAC blocks have an interior facing surface facing the load-bearing frame and an opposite exterior facing surface; d) attaching a first plurality of track support sections (e.g., girts) on the exterior surface of the exterior surface of the load-bearing frame; e) attaching a first plurality of track system sections to the first plurality of track support sections; f) inserting a first plurality of clip fasteners into the first plurality of track system sections such that the first plurality of clip fasteners is slidingly retained in the first plurality of track system sections wherein each of the first plurality of clip fasteners comprise a downward interlock stub and an upward interlock stub, further wherein each of the first plurality of clip fasteners is placed such that the downward interlock stub is inserted into the top groove of the first plurality AAC blocks; g) applying a layer of adhesive (e.g., thin-bed mortar) to the top surface of the first plurality AAC blocks; h) placing a second plurality of AAC blocks directly on top of the first plurality of AAC blocks wherein each of the blocks has a top groove and bottom groove, further wherein the top interlock stub of the first plurality of connection is inserted into the bottom groove of the second plurality of AAC blocks; i) repeating steps (d) through (h) until the desired exterior wall height is achieved and vertical internal cavity separating the AAC blocks and the load-bearing frame is achieved; j) applying an exterior finish to the exterior surface of the AAC blocks; k) injecting a polyurethane foam into the vertical internal cavity and allowing said polyurethane foam to expand and cure; and l) applying an interior finish to the interior surface of the load-bearing frame.
It will be understood by those skilled in the art that junctions between dissimilar materials (and sometime similar materials) and any protrusions through the finished walls (e.g., doors, windows, piping, ducts, structural members, etc.) may benefit from optional inclusion of one or more suitable flashings, counter flashings, drip caps, flexible sealants, caulks (e.g., siliconized caulks), mortars, adhesives, and the like, to limit water and/or vapor infiltration and/or to provide stability.
A number of standard testing methods are known in the structural engineering and construction related arts suitable for quantifying the desirable characteristics of the integrated building systems and compositions (or the components thereof) of the present invention such, but not limited to, levels of the water and vapor impermeability, thermal barrier properties, resistance to/prevention of thermal bridging, acoustic deadening/proofing properties (e.g., wherein an STC value is about 41 and/or an OITC value is about 33), shock absorbance, shear strength, ductility for seismic resistance, adhesive qualities, fire resistance/proofing, zero (or acceptably low) outgassing of toxic and/or noxious gases, resistance to rot, mold, insect, and animal damage, and the like. Those skilled in the art will be able to select the desired properties of the various components of the wall construction systems and materials for respective residential and/or commercial construction projects in view of local, state, national, and/or federal building codes, and/or conventions observed in a particular area. In preferred embodiments, the wall construction systems and materials are tested in accordance with, and prove to be suitable for the intended purpose under one or more American Society for Testing and Materials (“ASTM”) tests (e.g., ASTM C 518, ASTM D1622, ASTM D 2126, ASTM E84, ASTM E90, ASTM E96, ASTM E283, ASTM E330, ASTM E331, ASTM E564, and/or TAS 201, TAS 203 and the like).
There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components or construction steps set forth in the following descriptions or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. It is understood that the phraseology and terminology employed herein are for the purpose of the description and should not be regarded as limiting.
For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be made to the accompanying drawings and descriptive matter in which there are illustrated preferred embodiments of the invention. Other features and advantages of the present invention will become apparent from the following description of the preferred embodiment(s), taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A illustrates an isometric view of a typical section of the wall system assembly. FIG. 1B illustrates a typical elevation of the wall system assembly from the exterior of the building. FIG. 1C illustrates a typical elevation of the wall system assembly from the interior of the building. FIG. 1D illustrates a sectional elevation of the wall system assembly from the interior of the building.
FIG. 2 illustrates a typical section of the wall system assembly at the foundation.
FIG. 3 illustrates a plan view of a typical section of the wall system assembly at a corner wall and window jamb.
FIG. 4 illustrates a typical section of the wall system assembly at an intermediate floor.
FIG. 5 illustrates a typical section of the wall system assembly at a window head and window sill.
FIG. 6 illustrates a typical section of the wall system assembly at a slab foundation with exterior plaza.
FIG. 7 illustrates a typical sectional view of the wall system assembly from the interior of the building at a stem wall.
FIG. 8 illustrates cross sections of a typical track system and a clip fastener of the wall system assembly.
FIG. 9 illustrates a cross section of a typical shelf angle of the wall system assembly.
DETAILED DESCRIPTION
While several variations of the present invention have been illustrated by way of example in preferred or particular embodiments, it is apparent that further embodiments could be developed within the spirit and scope of the present invention, or the inventive concept thereof.
The invention comprises a novel wall system for residential and light commercial construction that incorporates lightweight construction material units such as AAC blocks. This wall system comprises an exterior wall composed of AAC blocks married to an interior wood or metal load-bearing (structural) framing. The AAC blocks would be anchored to the framing using novel construction clips. Furthermore, a cavity or space between the framing and the interior surface of the exterior wall comprising AAC blocks is injected with structural polyurethane foam insulation to adhere the framing and the walls together and to provide insulation, air-sealing, and vapor-proofing. The exterior of the AAC walls further comprises an exterior cementitious stucco finish that is waterproof. The interior of the load-bearing framing receives a typical interior finish.
FIGS. 1-7 generally illustrate isometric, plan, and section views of certain typical embodiments of the construction materials and construction methods of the present invention for constructing a novel wall system. In these embodiments, as is shown in the representative Figures a load-bearing frame (non-sheathed) 2 of wood and/or metal (e.g., steel) is erected with wind bracing 3 (See, FIG. 1B ) (e.g., steel wind bracing) on a conventional concrete foundation 1 . No sheathing is applied.
In particular, FIG. 1A shows a detailed isometric view of a section of track system 10 having slidingly retained therein clip fasteners 8 with interlock stubs 8 c and 8 d engaging/set to engage groove(s) 7 in AAC block 5 . Track section 10 is attached by attachment devices 9 (e.g., screws) to track support section 16 . Track support section 16 (girt) is attached to load-bearing frame 2 . Further, FIG. 1A shows a first course of AAC blocks 5 supporting a second course of AAC blocks 5 with a (leveling) layer of thin-bed mortar 6 in between the courses.
FIG. 2 illustrates the grade of the building surface (not numbered) exterior to the concrete foundation 1 . In one embodiment of the invention, the load-bearing frame 2 may be anchored to the concrete foundation 1 through bolts (not shown) about 7″ to about 9″ inwards from the exterior edge of the concrete foundation 1 .
The shelf angle 4 or starter piece is a continuous pultruded fiberglass shelf angle 4 that is attached 9 (e.g., screwed) to the load-bearing frame 2 at a level plane to create a level starter. Leveling grout 6 may be added underneath the shelf angles 4 at any gaps between the shelf angles 4 and the foundation 1 . The shelf angles 4 have a continuous interlock stub 4 d which fits into a bottom groove 7 of AAC blocks 5 . The shelf angles 4 also comprise a vertical leg 4 c that contains a traversing screw hole 4 b for affixing the shelf angle 4 to the load-bearing framing system 2 using screws or bolts 9 .
Shelf angle 4 is affixed continuously around the base of the load-bearing frame 2 at a level plane on top of the concrete foundation 1 . The interlock stubs 4 d of the shelf angles 4 form a level starter track. A thin-bed mortar 6 with a thickness of about 1/16″ to about ⅛″ or more is placed over the starter track and AAC blocks 5 are laid on the level starter track. The AAC blocks 5 each have two grooves 7 on the top and the bottom which may be approximately ½″ deep and ⅛″ wide. As the AAC block 5 is laid down onto the starter track, the interlock stubs 4 d of the shelf angles 4 are inserted into the bottom grooves 7 of AAC blocks 5 .
In another embodiment of the invention, an adhesive may be added to the grooves 7 to provide additional attachment of the AAC blocks 5 to the shelf angles and the various clip fasteners 8 disclosed in the invention.
In one embodiment of the invention, the AAC blocks are insect-proof, lightweight and insulating. In another embodiment of the invention, the AAC blocks 5 may have a thickness of from about 2″ to about 6″ or more, a height of from about 8″ to about 24″ or more and a length of from about 24″ to about 48″ or more, although, the present invention is not limited to particular lightweight construction units and/or AAC block dimensions. In the preferred embodiment of the invention, the AAC blocks 5 comprise a thickness of 3″ and a face of 24″×24″.
In particular embodiments, after the initial set of AAC blocks 5 are placed over the interlock stubs 4 d of the shelf angles through bottom grooves 7 , a plurality of track support sections 16 are horizontally (level) attached to the load-bearing framing with attachment devices 9 (e.g., screws) such that the track system sections 10 subsequently, or previously, attached thereto with attachment devices 9 (e.g., screws) are positioned to slidingly retain a plurality of clip fasteners 8 having upward projecting interlock stubs 8 c and downward projecting interlock stubs 8 d positioned to engage grooves 7 on one or more surfaces (e.g., top, bottom, sides, ends) of a plurality of AAC blocks 5 on a first, second, third, fourth, etc., course(s) of AAC blocks 5 during wall construction.
As illustrated in FIG. 8 , clip fastener 8 comprises a main body section 8 a that defines the horizontal axis of clip fastener 8 , and four protrusions therefrom: first, sliding anchorage portion 8 b that in turn comprises two legs in a “Y” shaped configuration emanating from main body section 8 a of clip fastener 8 ; second, an upward interlock stub 8 c ; and, third, a downward interlock stub 8 d . The sliding anchorage portion 8 b forms a first terminus of the clip fastener 8 . The upward interlock stub 8 c and the downward interlock stub 8 d , respectively, emanate from the main body 8 a of clip fastener 8 . The upward interlock stub 8 c and the downward interlock stub 8 d , respectively, forms a second terminus of clip fastener 8 . Each of legs of the sliding anchorage portion 8 b of clip fastener 8 ends in a semicircular inward curving hook shaped terminus. FIG. 8 also illustrates a cross section of a section of track system 10 . Track system 10 comprises main channel body 10 a and two perpendicular protrusions 10 b from the main body at the respective top and bottom of track system section 10 . In preferred embodiments, each of protrusions 10 b in turn terminate in inward facing beveled (or semicircular) ridge 10 c that is optimized to slidingly retain the mated semicircular ends of each of the legs of sliding anchorage portion 8 b of clip fastener 8 . FIG. 1A shows the semicircular ends of each of the legs of sliding anchorage portion 8 b of clip fastener 8 accepted by and slidingly mated with the corresponding protrusions 10 b of track system 10 . Each section of track system section 10 preferably further comprise a plurality of holes (not shown) that traverse main channel body section 10 a for receiving attachment devices 9 to thus secure the track system section 10 to the track support section 16 (girt) or secure it directly to the load-bearing fame 2 .
A plurality of clip fasteners 8 are slidingly retained in track system sections 10 setting the AAC blocks 5 away from the load-bearing frame 2 by from about 1″ to about 3½″ or more. Downward interlock stub 8 d is inserted into the top grooves 7 of the AAC blocks 5 and the upward interlock stub 8 c is inserted into the bottom groove 7 of the next layer of AAC blocks 5 .
In this embodiment of the invention, layers of clip fasteners 8 and AAC blocks 5 are placed on top of one another and married to the framing. In the preferred embodiment of the invention, the offset between the load-bearing frame 2 and the AAC blocks 5 is about 3½′.
In preferred embodiments, once the AAC blocks 5 have been set, the windows 13 (e.g., FIGS. 3 and 5 ), doors, electrical wiring and plumbing systems, and other systems and sub subsystems of the building structure may be installed.
In the present invention, the vertical cavity between the load-bearing framing 2 and the wall of AAC blocks 5 is injected with foamed-in-place medium-density closed-cell polyurethane foam 14 . Because the polyurethane foam 14 is adhesive and structural, all components of the wall and wall construction system are bonded into a unified composite construction of great strength. In one embodiment of the invention, the polyurethane foam 14 may be waterproof, vapor-proof and non-toxic with high thermal resistance. In a further embodiment of the present invention, the polyurethane foam 14 may have a water-vapor permeability of less than one perm and thermal performance of about R-5 per inch or greater. Conventional finishes such as plaster may be applied to the interior of the wall 15 (See, FIG. 2 ).
The exterior of the AAC blocks 5 receive a cementitious stucco finish 12 . In one embodiment of the present invention, the stucco finish 12 may be impact-resistant, waterproof and decorative in a variety of colors.
FIG. 3 illustrates a plan view of a typical section of the wall system assembly at a corner wall and window jamb. In this embodiment, incorporation of a window 13 into the wall structure is shown. The exterior of window 13 is sealed with siliconized caulk 17 . Similarly, FIG. 5 illustrates a sectional view of a typical section of the wall system assembly at a window head and sill. In this embodiment of the present invention, incorporation of a window 13 into the wall structure is shown. Lintels are created with a shelf angle 4 screwed to the lintel beam 11 of the load-bearing frame 2 .
FIG. 4 illustrates one embodiment of a sectional view at an intermediate floor of the wall system assembly. In this embodiment, a frame joist may separate the floors in the structure as known to those skilled in the art.
FIG. 6 illustrates a section view of a typical section of the wall system assembly at a slab foundation. In this embodiment, pavers 18 are shown as part of the exterior surface treatment on the slab foundation 1 .
FIG. 7 illustrates a typical sectional elevation of the wall system assembly from the interior of the building at a stem wall foundation. In this embodiment, one partial below grade 19 application of the wall construction materials and systems of the present invention is shown. In this embodiment, a drainage system 20 is optionally provided as known to those skilled in the art.
FIG. 9 illustrates a cross section view of the shelf angle 4 of the wall system assembly. In this embodiment, a horizontal base section 4 a and a hole 4 b traversing the vertical leg 4 c for attachment by an attachment device 9 to the load-bearing frame 2 as well as the continuous interlock stub 4 d are illustrated.
In one embodiment, the clip fasteners of the present invention may comprise lengths of 3″ to 10″. In another embodiment, the base surfaces of the clip fasteners of the present invention may comprise heights of ⅛″ to 4″ and widths of ⅛″ to 4″. In a further embodiment, the protrusions of the clip fasteners of the present invention may comprise heights of from about ⅛″ to about 4″ and widths of from about ⅛″ to about 4″. In one embodiment of the present invention, the resulting total wall thickness is from about 8″ to about 16″ or more.
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The present invention provides novel wall construction systems and materials for residential and commercial construction that incorporate grooved lightweight building material units (e.g., blocks, panels, and the like), a plurality of connection devices, a track system, and (injected) polyurethane structural foam. The wall construction system comprises building material units married to a building frame with a plurality of connection devices (e.g., clip fasteners) slidingly retained in a track system that is attached to the building's structural (e.g., load-bearing) framing. The building material units are joined to each other with a suitable binding agent. The cavity between the frame and the building material units is injected with an insulating structural polyurethane foam. The exterior of the wall is finished with a waterproof applied finish such as cementitious stucco. The interior of the wall is amenable to standard finish options.
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This application is a CIP of PCT/EP03/02999, filed Mar. 22, 2003.
BACKGROUND OF THE INVENTION
The invention relates to a cylinder block for an internal combustion engine having a plurality of cylinders with profiled sections in the area of a plane of a main crankshaft bearing structure.
Patent DE 43 24 609 C2 discloses a cylinder block for an internal combustion engine having a plurality of cylinders and lateral reinforcing structures in the form of longitudinal and vertical profiled sections. These hollow profiled sections are integrated in the casting forming the cylinder block. A plurality of longitudinal profiled sections are provided laterally, and a vertical profiled section is provided at each main bearing, the longitudinal profiled sections extending in the longitudinal direction of the engine and the vertical profiled sections following the profile of the side wall of the cylinder-crankcase, i.e. from the top initially parallel to the cylinder axis and then widening outward in the region of the crank case. The cavities of the profiled sections are designed such that medium can flow through them continuously.
By contrast, it is an object of the present invention to provide a cylinder-block having a reinforcing structure of longitudinal and vertical profiled sections in which a lateral camshaft can be mounted in close proximity to the cylinder walls.
SUMMARY OF THE INVENTION
In a cylinder-block for an internal combustion engine with a plurality of cylinders having longitudinal profiled sections in the form of lateral hollow reinforcement structures and vertical sections in the form of profiled reinforcement structures, in the region of a main bearing plane means are provided for supporting a lateral camshaft beneath the upper longitudinal profiled section, and, in the region of the bearing structure for the camshaft the vertical profiled section is divided in two.
The longitudinal profiled sections extending in the longitudinal direction of the engine and the vertical profiled sections following the profile of the side wall of the cylinder block, i.e. starting from the top, initially parallel to the cylinder and then outwardly in the region of the crank space. If the lateral camshaft is mounted beneath the longitudinal profiled section, that is next to the longitudinal profiled section, a narrow engine design can be achieved since the camshaft does not significantly increase the width of the internal combustion engine. However, the level where the camshaft is positioned i.e. the vertical position of the camshaft is predetermined thereby. Since, in the plane spanned by two adjacent longitudinal profiled sections, there are still the vertical profiled sections which extend perpendicular to the longitudinal profiled sections, in each main bearing mounting plane, the vertical profiled section is interrupted if the camshaft is arranged beneath a longitudinal profiled section. The vertical profiled sections are disposed in the plane the bearings of the camshaft, which are also the main crankshaft bearing planes. These planes are perpendicular to the longitudinal direction of the engine and extend in each case between two cylinders. According to the invention, the vertical profiled section is divided in two in the region of the camshaft bearings, so that a continuous flow connection with as far as possible a constant cross section is obtained and therefore a uniform or symmetrical loading on the high profiled section occurs in the event of bending or torsion of the cylinder-block. The camshaft alley, i.e. the space in which the camshaft is disposed, can likewise be designed as a longitudinal profiled section and therefore constitutes a second longitudinal profiled section beneath the upper longitudinal profiled section. In this way, a single casting core can be used to produce the reinforcing structure comprising high and longitudinal profiled sections, which results in considerable advantages in terms of manufacturing costs and the quality or tolerance of the positioning of the individual casting cores with respect to one another.
In one configuration of the invention, in each case a partial portion of the divided vertical profiled section is arranged in front of the bearing arrangement of the camshaft and a partial portion is arranged behind the bearing arrangement of the camshaft, as seen in the longitudinal direction of the engine. This means that despite crossing the camshaft, a continuous vertical profiled section is retained and the space required to bypass the bearing arrangement of the camshaft does not disrupt the external contour of the engine. The bearing which supports the camshaft is integrally formed by the cylinder block at the cylinder side of the divided vertical profiled section and, on the opposite side, by the outer wall of the vertical profiled section.
In a further configuration of the invention, the vertical profiled section forms at least an upper and a lower cavity by closure elements. The introduction of closure elements makes it easy for the cavities of the longitudinal and vertical profiled sections to be divided into two separate portions in order for different media to be routed therein without, however, losing the advantage of a common casting core which is simple to produce and allows accurate blank castings to be produced on account of its inherent stability.
In a further configuration of the invention, coolant can flow through an upper longitudinal profiled section and an upper cavity arranged on the opposite side of the cylinder-block from the bearing arrangement for the camshaft. In this way, the cavity of the reinforcing profiled sections can be ideally utilized as a coolant distributor passage to the individual cylinders, since it extends over the entire length of the cylinder-block and has a virtually constant cross section. A supply of coolant which is as uniform as possible is only required on one side of the engine; the coolant leaves the engine for example via the cylinder head.
In a further configuration of the invention, a lower cavity of the longitudinal and vertical profiled sections is in communication with an oil space of the cylinder-block and serves as a pressurized-oil supply line or a line for crankcase ventilation.
In still a further configuration of the invention, on the side of the cylinder block, on which the bearing structures for the camshaft are arranged, elements of a valve operating mechanism are provided in an upper cavity of the vertical profiled section and/or in the longitudinal profiled section. Since the camshaft is mounted in, or beneath, a longitudinal profiled section which is in communication with the upper longitudinal profiled section, i.e. both profiled sections are filled with lubricating oil or oil mist, it is advantageous for these spaces to be used for the actuating elements of the valve operating mechanism, such as for example push rods. This means that the external contour of the internal combustion engine or the crankcase is not significantly increased in size despite the longitudinal profiled sections, vertical profiled sections, a lateral camshaft and the valve operating mechanism.
The invention will become more readily apparent from the following description of exemplary embodiments thereof illustrated in a simplified representation in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a perspective illustration of a cylinder block according to the invention,
FIG. 2 shows in a longitudinal sectional view taken along line II—II of FIG. 1 a camshaft bearing alley,
FIG. 3 shows a perspective illustration of a casting core of the camshaft side of the cylinder block,
FIG. 4 shows a perspective illustration of a casting core of the side of the cylinder block from the camshaft, and opposite the side shown in FIG. 3 , and
FIG. 5 is a lateral plan view of a casting core of the opposite side of the cylinder block opposite the camshaft.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a cylinder-block 1 having a plurality of cylinders 2 and a crank space 3 . In the crank space 3 , a crankshaft bearing 4 is located between two cylinders 2 . A cavity 5 , known as the camshaft bearing alley, in which a camshaft (not shown) is mounted, is arranged on the outer side of the cylinder block in the transition area from the upper cylinder part of the cylinder block 1 to the crank space 3 . This cavity 5 is formed as a longitudinal profiled section. Above this cavity 5 there is a further, upper, longitudinal profiled section 6 , which serves to longitudinally reinforce the cylinder block 1 and in particular to reinforce the cylinder cover 7 and is likewise hollow. Furthermore, tappets (not shown) of a valve-actuating mechanism are accommodated in this longitudinal profiled section 6 . The guides 8 for the tappets and the passages 9 for the push rods are provided in the cylinder-block 1 . A reinforcing hollow longitudinal profiled section 10 is likewise arranged at the lower end of the cylinder block.
Three hollow longitudinal profiled sections 10 ′, 11 , 12 are likewise arranged on the opposite side of the cylinder-block 1 from the camshaft, the longitudinal profiled section 10 being arranged at the lower end of the cylinder-block corresponding to the longitudinal profiled section 10 on the camshaft side. Since neither camshaft nor tappets are provided on this side of the cylinder block, the longitudinal profiled sections 11 , 12 are of simpler design, i.e. are rectilinear without any sudden changes in cross-section. At the passage 13 , a coolant flows from the longitudinal profiled section 11 , which is designed as a coolant distributor passage, into the cooling jacket 14 surrounding the cylinders 2 .
FIG. 2 shows the cylinder-block 1 according to the invention as shown in FIG. 1 in the form of a longitudinal section through the camshaft bearing alley 5 over one full and two adjacent half cylinders 2 . From the longitudinal profiled section 6 , hollow high profiled sections 15 lead via the cavity of the camshaft bearing alley 5 to the lower edge of the cylinder block 1 . The vertical profiled sections 15 are arranged in the main bearing plane between two cylinders 2 . The camshaft (not shown) is mounted in camshaft bearings 16 , which for their part are connected to the cylinder block 1 by casting structures in front of, and behind, the sectional plane shown in the figure. The lubricant for the camshaft is supplied through the bores 17 in the camshaft bearing 16 . The tappets (not shown) for actuating the gas exchange valves are guided in the guides 8 and project out of the cylinder-block 1 into the cylinder head (not shown) through the passages 9 . The rectilinear profile of the high profiled sections 15 from the longitudinal profiled section 6 to the lower edge of the cylinder block 1 is interrupted by the camshaft bearing alley 5 . In the region of the camshaft bearings 16 , the vertical profiled sections 15 are divided in two which extend around the camshaft bearings. As seen in the direction of the camshaft bearing alley 5 , the bearing cavity is formed by one part of the vertical profiled section 15 extending in front of the camshaft bearing 16 , and the other part extending behind the camshaft bearing 16 . This results in a continuous, virtually constant flow cross-section from the top downward.
FIG. 3 shows the casting core 18 for the reinforcing structure of the cylinder block 1 in a perspective view of the camshaft side as seen from the outside. The casting core 18 is composed in particular of the portions for the vertical profiled sections 15 ′ and the longitudinal profiled sections 5 ′, 6 ′, 10 ′. Moreover, the drawing shows cores for the passages 9 ′ and the guides 8 ′ for the valve-actuating devices. Since the guides 8 ′ comprise an integrally cast part which is subsequently drilled, they are formed as a cavity or void in the casting core, which consists, for example, of molding sand.
FIG. 4 shows the casting core 19 of the reinforcing structure of the cylinder block 1 in the form of a perspective view as seen from the inside toward the side of the cylinder block opposite the camshaft. The casting core 19 is composed in particular of portions for the vertical profiled sections 15 ′ and for the longitudinal profiled sections 10 ′, 11 ′. The passages 13 ′ for the coolant are arranged at the portion for the upper longitudinal profiled section 11 ′. The projections 20 ′ which protrude from the casting core result in apertures in the finished cylinder block 1 . During casting, they are used to hold and connect the various casting cores to one another, and in the finished cylinder-crankcase form flow passages, for example for transferring coolant from the cylinder block to the cylinder head.
FIG. 5 shows the casting core 19 of FIG. 4 in a side view from the inside outward in the transverse direction of the engine. In addition to the portions for the longitudinal profiled sections 10 ′, 11 ′ and the vertical profiled sections 15 ′, this figure also shows the transition location 21 from the vertical profiled section 15 ′ to the upper longitudinal profiled section 11 ′. According to the invention, on the opposite side from the camshaft, the profiled structure comprising longitudinal and vertical profiled sections is cast around a casting core 19 , but the cavities which result from the casting core are divided into two separate cavities by closure elements at the transition location 21 .
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In a cylinder-block for an internal combustion engine with a plurality of cylinders having longitudinal profiled sections in the form of lateral hollow reinforcement structures and vertical sections in the form of profiled reinforcement structures, in the region of a main bearing plane means are provided for supporting a lateral camshaft beneath the upper longitudinal profiled section, and, in the region of the bearing structure for the camshaft the vertical profiled section is divided in two.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 11/364,527, filed Feb. 28, 2006. The entire disclosure of the aforesaid application is incorporated herein in its entirety by reference.
FIELD OF THE INVENTION
This invention relates to chlorine dioxide compositions. In particular, the invention relates to a novel liquid chlorine dioxide mixture for cleaning and sanitizing.
BACKGROUND OF THE INVENTION
Chlorine dioxide in low concentrations (i.e. up to 1,000 ppm) has long been recognized as useful for the treatment of odors and microbes, see U.S. Pat. No. 6,238,643. Its use is particularly advantageous where microbes and/or organic odorants are sought to be controlled on and around foodstuffs, as chlorine dioxide functions without the formation of undesirable side products such as chloramines or chlorinated organic compounds that can be produced when elemental chlorine is utilized for the same or similar purposes.
Unfortunately, chlorine dioxide can be explosive at concentrations above about 0.1 atmosphere. Therefore, chlorine dioxide gas is not manufactured and shipped under pressure like other industrial gases, and conventional methods of on-site manufacture require not only expensive generation equipment but also high levels of operator skill to avoid generating dangerously high concentrations. These problems have substantially limited the use of chlorine dioxide to large commercial applications, such as pulp and paper bleaching, water treatment, and poultry processing, where the consumption of chlorine dioxide is sufficiently large to justify the capital and operating costs of expensive equipment and skilled operators for on-site manufacture.
Commercially, chlorine dioxide is produced from a variety of aqueous solutions of certain chlorine-containing salts, as disclosed for example in U.S. Pat. No. 5,009,875.
Attempts have also been made to produce chlorine dioxide using mixtures of solid reagents. Generally, the prior art has focused on three systems for chlorine dioxide production using solid reagents. One system employs a solid mixture of a metal chlorite and an acid in a liquid, aqueous environment. A second system combines a metal chlorite and a solid acid where chlorine dioxide gas is released under dry conditions. A third system employs the combination of a metal chlorite and a solid organic anhydride to generate a highly concentrated flow of chlorine dioxide which must be diluted with a constantly flowing stream of inert gas.
Aqueous solutions of chlorine dioxide are also known in the art. Two types of synthesis processes are generally used to provide chlorine dioxide solutions for commercial uses, such as poultry chiller water purification, wash-water purification, potable water treatment and as a teat dip for the control of non-human mammalian mastitis.
The first type of synthesis process is based on the manual combination of two aqueous solutions; one containing a source of chlorite anions and another being acidic. The solution containing chlorite anions is usually a solution of sodium chlorite having a concentration of between about 100 ppm and about 5% by weight and having a pH of about 13. The acidic solution may contain any acid capable of providing a pH below about 8.5 after the solutions are mixed. Such acids include citric acid, lactic acid, hydrochloric acid, sulfuric acid, and dissolved carbon dioxide (i.e., sodium bicarbonate). The antimicrobial performance of the resultant solutions depends upon the degree to which the chlorite anions from the chlorite source solution are converted to free molecular chlorine dioxide (“Chlorine Dioxide”) in the solution, as chlorine dioxide is the effective agent for both antimicrobial and deodorization activity.
In one variation on this synthesis process, the pH of the sodium chlorite solution is reduced from about 13 to about 8 using the acidic solution. Chlorite anion is thus converted to chlorine dioxide via the reaction below.
5ClO 2 − +5H + 4ClO 2 +HCl+2H 2 O
Such solutions having a pH of about 8 are generally referred to in the industry as “stabilized” chlorine dioxide solutions, and usually contain between about 100 ppm and 5% of a mixed solution of chlorine dioxide and unconverted chlorite anion. Because the acid concentration is relatively low at a pH of 8, the typical ratio of chlorine dioxide to chlorite anion in a stabilized chlorine dioxide solution is less than 0.01. Therefore, for a given initial concentration of chlorite anion, stabilized chlorine dioxide solutions are relatively weak antimicrobial agents due to their low conversion of chlorite anion to chlorine dioxide. Also, since the stabilized chlorine dioxide solutions are typically supplied at a concentration of less than about 5% by weight sodium chlorite, shipping and storage of the solution is relatively expensive due to the high weight of water that must be transported with the sodium chlorite.
Chlorite anion is generally stable in stabilized solutions (pH 8) and thus has an advantageously long shelf life. However, the chlorite anions are typically activated just prior to use to improve effectiveness. This is accomplished by the addition of a strong acid to lower the pH to below about 3.5 and convert more chlorite anion to chlorine dioxide via the reaction shown above. Since the activation process involves the addition of a strong acid to lower the pH, a high level of operator skill is required to handle, measure and mix the acid with the stabilized chlorine dioxide solution. Also, since the activation process results in a solution having a pH of less than about 3.5, such activated solutions are not well suited to work in combination with, for example, detergents which work best under alkaline or neutral pH conditions. Contact of these solutions with many metals should also be limited because of possible metallic corrosion by the acidic solution.
Such activated solutions typically have a ratio of chlorine dioxide to chlorite anion below about 0.05 when the solution is acidified to a pH of about 3. A higher ratio of chlorine dioxide to chlorite anion can be achieved in such activated solutions, but doing so is dangerous and requires extreme operator skill. Achieving a ratio of chlorine dioxide to chlorite anion above about 0.05 requires further acidification to a much lower pH than 3 (typically less than 2) and often requires that the further acidification be performed at concentrations of chlorite anion above about 5000 ppm. Under such conditions of extremely low pH and high chlorite ion concentration a sufficient chlorine dioxide concentration can be generated in such solutions such that the vapor pressure of gaseous chlorine dioxide in equilibrium with the solution approaches the explosive range. Therefore, manual acidification (i.e. without chlorine dioxide generation equipment as discussed below) is not commonly employed in producing solutions having a high ratio of chlorine dioxide to chlorite anion.
In the second type of chlorine dioxide solution synthesis process, chlorine dioxide solution is generated from either a sodium chlorite solution or stabilized chlorine dioxide solution using chlorine dioxide generation equipment at the point of use. The generated solution typically has a ratio of chlorine dioxide to chlorite anion of between about 10 and 25, and as a result such solutions are highly effective antimicrobial agents. Since generated chlorine dioxide solution is typically used shortly after generation, the relatively high decomposition rate of chlorine dioxide in solution is unimportant. Also, since aqueous sodium chlorite is commercially available at higher concentrations than are typically available in the form of stabilized chlorine dioxide solutions, the cost of storing and shipping the aqueous sodium chlorite solutions can be lower when compared to stabilized chlorine dioxide solution. However, the high cost of the chlorine dioxide generation equipment and the high level of operator skill needed for its operation make generated chlorine dioxide solution best suited to relatively large applications such as water treatment and poultry processing where the consumption of chlorine dioxide is sufficiently large thereby justifying the such high capital and operating costs.
In addition to the two types of commercial synthesis processes for chlorine dioxide solution discussed above, solutions containing chlorine dioxide and having a high ratio of chlorine dioxide to chlorite anion can be generated by absorption of gaseous chlorine dioxide into water. Chlorine dioxide is first produced in solution by conventional means, e.g. acid activation of a solution of sodium chlorite. Inert carrier gas, typically air or nitrogen is then bubbled through the activated solution picking up some of the chlorine dioxide. That gaseous mixture of chlorine dioxide and carrier gas is then bubbled through a second vessel containing water where the chlorine dioxide is dissolved to produce a solution of chlorine dioxide typically having a ratio of chlorine dioxide to chlorite anion of about 20 or higher. While it is possible to produce substantially pure solutions of chlorine dioxide in this manner, it requires a very high level of operator skill and is rarely done outside of the laboratory.
Attempts have been made to reduce the cost of generating chlorine dioxide solutions by using mixtures of alkaline chlorite salts and acidic dry powders which, upon addition to water, acidify the water and generate chlorine dioxide via reaction described above. U.S. Pat. No. 2,022,262, discloses stable stain removing compositions comprising a dry mixture of a water soluble alkaline chlorite salt, an oxalate, and an acid. Since alkaline chlorites are strong oxidizers and corrosively caustic, a relatively high level of user skill is needed to employ this process.
U.S. Pat. No. 2,071,094 discloses deodorizing compositions in the form of dry briquettes comprising a dry mixture of a soluble chlorite, an acidifying agent, and a filler of lower solubility. Generation of chlorine dioxide begins as the briquette dissolves in water. This process is suitable for unskilled users, but still requires that the resultant solution be produced at an acidic pH.
U.S. Pat. No. 2,482,891 discloses stable, solid, substantially anhydrous compositions comprising alkaline chlorite salts and organic acid anhydrides which release chlorine dioxide when contacted with water. The patent disclosure indicates that the preferred solution is highly concentrated and consequently would have been at an acidic pH. As such, this process suffers from the same limitations as the '262 and '091 patents mentioned above.
U.S. Pat. No. 4,585,482 discloses a long-acting biocidal composition comprising a chlorine dioxide liberating compound and a hydrolyzable organic acid-generating polymer. Methods are disclosed for producing dry polymer encapsulated microcapsules containing such compositions and water such that the resultant dry materials release chlorine dioxide gas. The primary purpose of the polymer encapsulating film of the '482 patent is to provide for hard, free flowing particles, and to protect against the loss of water from the interior of the microcapsule. Immersing the microcapsules in water would produce a chlorine dioxide solution. Producing chlorine dioxide solution in this manner would eliminate the complications of measuring and mixing reagents and the cost of capital equipment that characterize the prior art. In addition, the solution pH need not be acidic so it would be feasible to produce chlorine dioxide in a detergent solution. However, the materials of the '482 patent are not storage stable because chlorine dioxide is released soon after manufacturing. Furthermore, chlorine dioxide is released over a period of several days, so the materials of the '482 patent are unsuitable for quickly preparing a useable chlorine dioxide solution. Finally, once mixed in water the microcapsules cannot be removed from the water in a simple fashion. Typically the microcapsules must be separated by a process such as filtration.
The present assignee manufactures Aspetrol® chlorine dioxide generating tablets. The tablets are used in a wide array of applications such as to oxidize foul smelling compounds, deodorize areas, disinfect, etc. Assignee's patents directed to chlorine dioxide generating tablets include U.S. Pat. Nos. 6,699,404 and 6,432,322. These patents disclose solid bodies for preparing highly converted solutions of chlorine dioxide when added to water. The solid body comprises a metal chlorite such as sodium chlorite, an acid source such as sodium bisulfate and, optionally, a source of free halogen such as the sodium salt of dichloroisocyanuric acid or a hydrate thereof.
U.S. Pat. No. 6,238,643, also issued to the present assignee, discloses a method of producing an aqueous solution of chlorine dioxide from the reaction of chlorine dioxide generating components. The chlorine dioxide generating components are a metal chlorite and an acid forming component which do not react to produce chlorine dioxide in the substantial absence of water. The chlorine dioxide generating components are disposed in an enclosed space bounded at least in part by a membrane that is water and/or water vapor permeable but impermeable to the chlorine dioxide generating components contained therein. The membrane-bounded space containing the chlorine dioxide generating components is contacted with liquid water so the chlorine dioxide may generate and pass out through the membrane into the liquid water forming the aqueous solution of chlorine dioxide.
One problem with chlorine dioxide compositions, in particular, those formed with alkali metal chlorites and acid, whether solid or liquid, is that the resultant composition results in an acidic solution that is corrosive to metals. Thus, a chlorine dioxide solution is desired that will sanitize and cleanse especially metal objects without harming substrates on which it is being used. In accordance with the present invention, a chlorine dioxide solution is provided that inhibits metal corrosion.
SUMMARY OF THE INVENTION
This invention relates to an improved chlorine dioxide solution or liquid mixture containing a phosphate and, as well, to a composition for forming the chlorine dioxide and phosphate liquid mixture. This improved chlorine dioxide solution is used to clean and/or sanitize while inhibiting metal corrosion. The corrosive nature of the chlorine dioxide solution is lessened due to the addition of phosphate to the composition.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a graph of data showing the average corrosion potential for phosphate concentrations versus the weight ratio of phosphate to chlorine species in solutions.
FIG. 2 is a graph of corrosion potential relative to differing amounts of phosphate and lauryl sulfate surfactant.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is directed toward an improved cleaning and/or sanitizing chlorine dioxide liquid mixture or solution comprising a phosphate (“liquid mixture” or “solution”) and to a composition for forming the improved chlorine dioxide liquid mixture comprising the phosphate (“forming composition”). The phosphate containing chlorine dioxide solution of the present invention is less corrosive (i.e., reduced corrosivity) relative to the chlorine dioxide solutions of the prior art. The prior art acidic chlorine dioxide solutions are recognized as being corrosive when used at high concentrations (>10 ppm), for long periods of time or when used repeatedly for shorter times. Here, the presence of the phosphate in the chlorine dioxide solution inhibits metal corrosion. In particular, the corrosiveness of the prior art solutions are corrosive when their pH is low.
The liquid mixture of the present invention comprising chlorine dioxide and phosphate is formed using any of several types of precursors such as liquid solutions, dry tablets (solid bodies), briquettes, granules, powders or combination thereof which when in liquid phase produces a mixture containing chlorine dioxide and phosphate anions. The resultant solution is capable of cleaning and/or sanitizing and, depending upon its pH, removing mineral scale while being less corrosive to metals than prior art solutions.
The pH of the liquid mixture can vary from very low (<2) to as high as about 12.5. Chlorine dioxide disproportionates to chlorite and chlorate anions above a pH of about 11, and at pH>12.5 the rate of disproportionation is too high to produce a practically useful chlorine dioxide solution. At pH below about 2, acidic corrosion can be an issue even when phosphate is present. When limescale removal is an important function of the liquid mixture, the pH is preferably about 2.5-3.5. For the minimum corrosivity of the liquid mixture the pH is preferably above 3.5, more preferably above 4, and most preferably above 4.5.
The pH of the liquid mixture may result from the inherent conditions of chlorine dioxide generation used to produce the liquid mixture, or it may be the result of pH adjustment after the generation of chlorine dioxide. For example, if the liquid mixture is produced by acidification of a sodium chlorite solution using phosphoric acid to a pH of about 2 (the low pH necessary to achieve substantial conversion of chlorite anion to chlorine dioxide), then alkali may be added to the pH 2 chlorine dioxide solution to increase its pH to >2.5. Examples of suitable alkaline materials are inorganic hydroxides, such as sodium hydroxide, magnesium hydroxide, potassium hydroxide, and calcium hydroxide; metal carbonates of strong bases, such as sodium carbonate, and potassium carbonate; and a variety of other materials known in the art to increase the pH of aqueous solutions. Preferred materials to increase the pH of an overly acidic liquid mixture comprising chlorine dioxide and phosphate anions are those which will buffer the pH at a preferred level between about 2.5 and <12. For example, sodium acid carbonate (NaHCO 3 ) will buffer the pH of the liquid mixture at about 8. Sodium citrate will buffer the pH at about 4.5.
Alternatively, the pH of the liquid mixture comprising chlorine dioxide and phosphate may inherently be within the desired range after synthesis of the chlorine dioxide. For example, if solid bodies of the type disclosed in U.S. Pat. Nos. 6,699,404 and 6,432,322 are used to produce the chlorine dioxide, the pH of the resultant liquid mixture is typically within the preferred range upon synthesis. It is still within the scope of this invention, though, to further adjust the pH of such liquid mixtures to another pH within the preferred range by the addition of materials which will increase or decrease the pH of the mixture.
The chlorine dioxide forming composition comprising phosphate used to produce the liquid mixture may be composed of a metal chlorite, an acid source, an effective amount of phosphate used to reduce the corrosivity of the resultant liquid mixture, optionally a halogen, and optionally a surfactant. If the acid source is an acid phosphate, excess acid may be required to convert the metal chlorite to chlorine dioxide and provide the effective amounts of phosphate to inhibit corrosion. The liquid mixture can be produced by mixing aqueous solutions of the forming composition constituents or by mixing particulate forming composition ingredient(s) with water or aqueous solutions of the forming composition constituents. The liquid mixture will typically be in the form of a solution, but may also encompass suspensions, emulsions and other undissolved phases such as an emulsion of chlorine dioxide/phosphate solution in a light hydrocarbon liquid.
The aqueous solution(s) of the forming composition may include an aqueous metal chlorite solution, an aqueous acid source, an aqueous phosphate solution, water alone, water with additional ingredients including organic solvents such as hydrocarbons, lower alcohols, aldehydes, ketones, etc. The particulate forming composition ingredients used for forming the liquid mixture include particulate metal chlorite, particulate acid, and particulate phosphate. In a preferred method of forming the liquid mixture, the particulate forming composition ingredients used to produce the liquid mixture will be disposed in a solid body. The solid body will comprise particulate forming composition ingredients such as particulate metal chlorite, particulate acid, and optionally particulate phosphate. The resultant liquid mixture will be acidic having a pH of preferably below about 4 to convert chlorite anion to chlorine dioxide and to provide for the removal of mineral scale when used as a cleaner/sanitizer. Regardless of how the liquid mixture is made, it is desirable to minimize the concentration of chloride anion in the solution to improve its compatibility with metallic surfaces, particularly ferrous metal surfaces.
The metal chlorite employed in the present invention can generally be any metal chlorite. Preferred metal chlorites are alkali metal chlorites, such as sodium chlorite and potassium chlorite. Alkaline earth metal chlorites can also be employed. Examples of alkaline earth metal chlorites include barium chlorite, calcium chlorite, and magnesium chlorite. The most preferred metal chlorite used herein is sodium chlorite. In some cases, a metal chlorate may be used instead of a metal chlorite.
The acid source may include inorganic acid salts, salts comprising the anions of strong acids and cations of weak bases, such as aluminum chloride, aluminum nitrate, cerium nitrate, and iron sulfate. Acids that can liberate protons into solution when contacted with water, for example, a mixture of the acid ion exchanged form of molecular sieve ETS-10 (see U.S. Pat. No. 4,853,202) and sodium chloride; organic acids, such as citric acid and tartaric acid; and mixtures thereof. The acid source, in particular applications of the present invention, is preferably a particulate solid material which does not react substantially with the metal chlorite during dry storage, however, does react with the metal chlorite to form chlorine dioxide when in the presence of the aqueous solution. As used herein the term “acid source” shall generally mean a particulate solid material which is itself acidic or produces an acidic environment when in contact with liquid and metal chlorite. The acid source may be water soluble or substantially insoluble in water. The preferred acid sources are those which produce a pH of below about 4, more preferably below about 3.
Examples of preferred substantially water soluble acid sources include, but are not limited to, water soluble solid acids such as boric acid, citric acid, tartaric acid, water soluble organic acid anhydrides such as maleic anhydride, and water soluble acid salts such as calcium chloride, magnesium chloride, magnesium nitrate, lithium chloride, magnesium sulfate, aluminum sulfate, sodium acid sulfate (NaHSO 4 ), sodium dihydrogen phosphate (NaH 2 PO 4 ), potassium acid sulfate (KHSO 4 ), potassium dihydrogen phosphate (KH 2 PO 4 ), and mixtures thereof. The most preferred acid source is sodium acid sulfate (sodium bisulfate). Additional water soluble acid sources will be known to those skilled in the art and are included within the scope of the present invention.
The phosphate employed in the present invention may comprise phosphate anions (PO 4 −3 ); complex phosphate anions including pyrophosphates (P 2 O 7 −4 ), polyphosphates, and the like; or organic phosphates such as organic esters. Examples of phosphates used herein include phosphoric acid (H 3 PO 4 ), a strong acid; tetrasodium pyrophosphate (Na 4 O 7 P 2 ); trisodium phosphate (Na 3 PO 4 ), which is a strong base; and sodium dihydrogen phosphate (NaH 2 PO 4 ) a weak acid. Sodium dihydrogen phosphate (NaH 2 PO 4 ) is the preferred phosphate. If an acid phosphate is used as the acid source, then excess acid is required to convert the metal chlorite into chlorine dioxide and as well as to provide an effective corrosion-inhibiting amount of phosphate in the mixture. Generally, regardless of the pH of the phosphate used, an acid source will be employed along with the phosphate to make the present solution.
Suitable examples of the free halogen source used in the solid bodies include dichloroisocyanuric acid and salts thereof such as sodium dichloroisocyanurate and/or the dihydrate thereof (alternatively referred to as the sodium salt of dichloroisocyanuric acid and/or the dihydrate thereof and hereinafter collectively referred to as “NaDCCA”), trichlorocyanuric acid, salts of hypochlorous acid such as sodium, potassium and calcium hypochlorite, bromochlorodimethylhydantoin, dibromodimethylhydantoin and the like. The preferred source of the free halogen is NaDCCA.
Suitable surfactant components may be cationic, anionic, and non-ionic. Possible anionic surfactants may be soaps such as sodium oleate (NaOA), fatty acid salts, sodium dodecyl sulfate (SDS), other alkyl sulfate salts, and alkylbenzene sulfonates (ABS). Possible cationic surfactants may include cetyl trimethylammonium bromide (CTAB) and other alkyltrimethylammonium salts, cetyl pyridinium chloride, polyethoxylated tallow amine, alkyl amine salts and quaternary ammonium salts such as alkyl dimethyl benzyl ammonium chloride. Examples of non-ionic surfactants include alkyl poly(ethylene oxide), alkyl polyglucosides, nonyl phenol ethoxylate, polyoxyethylene fatty acid esters, polyoxyethylene alkyl amines, and alkylol amines.
The amount of surfactant needed will depend upon the chlorine dioxide concentration in the solution, the pH, the phosphate type and concentration, and other factors. It is within the ability of one skilled in the art to determine an optimum and a minimum necessary concentration. In some cases, combining surfactant with phosphate shows some beneficial effect to improve (reduce) corrosion from chlorine dioxide solutions than just using phosphate alone. By itself, the surfactant had little effect, but when the surfactant was combined with phosphate there was much greater positive effect than the sum of the two individual effects. The amount of surfactant used may range at about 0.50-10 wt. %, specifically 0-8 wt. %, more specifically 2-5 wt. %.
As mentioned above, the preferred method for forming the liquid mixture of the present invention involves using solid bodies. Here, particulate solid components are collectively disposed in a body, such as a unitary body, and then added to the aqueous solution. Solid bodies are discussed in commonly assigned U.S. Pat. Nos. 6,432,322 and 6,699,404 and are incorporated herein by reference.
Solid bodies, e.g. tablets, comprise a particulate metal chlorite such as sodium chlorite, a particulate acid source such as sodium bisulfate, optionally a particulate phosphate such as sodium dihydrogen phosphate, optionally a particulate source of free halogen such as the sodium salt of dichloroisocyanuric acid or a hydrate thereof, and optionally a particulate surfactant. If an acid phosphate is used as the acid source, then excess acid is required to convert the metal chlorite into chlorine dioxide and as well as to provide a separate phosphate in the mixture. Preferably the solid body is anhydrous containing less than about 1% wt. of free moisture-moisture that can be evolved at 100 degree Celsius. The solid body is suitable for producing the liquid mixture comprising chlorine dioxide with phosphate when immersed in water.
As used herein, the term “solid body” means a solid shape, preferably a porous solid shape, comprising a mixture of granular particulate ingredients wherein the size of the particles comprising the ingredients is substantially smaller than the size of the solid body. Such solid bodies may be formed by a variety of means known in the art, such as tableting, briquetting, extrusion, sintering, granulating and the like. The preferred method of forming such solid bodies is by compression, also known as tableting. For reasons of convenience, hereinafter references to tablets and tableting shall be understood to be representative of solid bodies made by any method.
In producing the solid bodies, the metal chlorite comprises an alkali or alkaline earth metal chlorite, preferably sodium chlorite, and most preferably technical grade sodium chlorite comprising nominally 80% by weight sodium chlorite and 20% by weight stabilizing salts such as sodium hydroxide, sodium carbonate, sodium chloride, sodium nitrate and/or sodium sulfate. Suitable acid sources and phosphates used within the solid bodies are similar to those mentioned above under forming composition ingredients.
Surprisingly, a very high conversion rate of the chlorite anion to chlorine dioxide is obtained by use of the tablets of the present embodiment of this invention. Thus, when the equivalent weights of tablet ingredients in powdered form are added to the same volume of water as the corresponding tablet, a much larger amount of chlorine dioxide is produced by the tablet than from the powder. Reasonable variations in stirring rate and/or water temperature have little to no effect on this surprising phenomenon.
Although not wishing to be bound by theoretical considerations, it is believed that the very high conversion rate of chlorite anion to chlorine dioxide resulting from the use of the tablets of the present embodiment of the invention occur because the tablets either contain or develop a pore structure. Such pore structure facilitates the penetration of water therein, thereby dissolving reagents into solution within the pores and producing advantageous conditions for the conversion of chlorite anion to chlorine dioxide within the pores.
It is known in the art that the rate of the reaction wherein chlorite anion is converted to chlorine dioxide under acidic conditions is of a very high order in both the concentration of chlorite anion and acidity. Increasing those concentrations dramatically increases the rate of chlorine dioxide formation.
It is believed that when water penetrates into the pore structure of the tablet, the water dissolves soluble constituents from the tablet and thereby forms a substantially saturated acidic solution of chlorite anion within the pores. Accordingly, the conversion rate of chlorite anion to chlorine dioxide is high. Nevertheless, despite the high rate of chlorine dioxide formation, a pore network must remain intact for a sufficient period of time to allow the conversion reaction to proceed to the desired degree. Once the reagents have dissolved into solution, the further conversion of chlorite anion to chlorine dioxide is very small.
The pore size and pore volume ranges required to facilitate the desired degree of conversion of chlorite anion to chlorine dioxide will depend upon many factors, e.g., the particular combination of reagents in the tablet, the size of the tablet, the shape of the tablet, the temperature of the water, other chemicals dissolved in the water, the desired degree of conversion of chlorite anion to chlorine dioxide, the desired amount of free halogen to be delivered into the solution, etc. Accordingly, it is not believed that there is a single optimum range of pore sizes or pore volumes that will produce an optimum result.
It is within the capability of one skilled in the art to vary the pore size and the pore volume of a tablet to achieve the desired result in respect to the characteristics of the chlorine dioxide solution. For example, the pore size and pore volume may be varied by varying the particle size of the powder used to prepare the tablet or by varying the compaction force used to form the tablet or by varying both the particle size and the compaction force. Larger particles of powder will generally produce larger pores and more pores in the tablet. Increasing compaction force will generally reduce both the size and volume of the pores in the tablet.
The tablets of the present embodiment of this invention have been observed to rapidly produce a highly converted solution of free molecular chlorine dioxide, meaning that the conversion ratio (chlorite anion to chlorine dioxide) is 0.25 or above. Preferably, the conversion ratio is at least 0.50, more preferably at least 0.60, and most preferably at least 0.75. The term “conversion ratio” used herein means the calculated ratio of the free chlorine dioxide concentration in the product solution to the sum of free chlorine dioxide plus chlorite ion concentrations in the product solution. Further, the chlorine dioxide solution is rapidly produced in a safe and controlled manner, and when the chlorine dioxide concentration so produced is at typical use levels (about 0.1 to about 1,000 ppm, preferably about 0.5 to about 200 ppm, by weight) in typical tap water, the solution will contain substantially no free chlorine or other free halogen and will have a generally neutral pH.
The term “rapidly produced” as used herein means that total chlorine dioxide production is obtained in less than about 8 hours, preferably in less than about 2 hours and most preferably in less than about 1 hour. The term “no free chlorine or other free halogen” used herein means that the concentration of free chlorine or other free halogen in solution is less than the concentration of chlorine dioxide in said solution on a weight basis, preferably less than ½ the concentration of chlorine dioxide in said solution, more preferably less than ¼ the concentration of chlorine dioxide, and most preferably no more than 1/10 the concentration of chlorine dioxide, on a weight basis.
The term “generally neutral pH” used herein means that the pH is higher than that normally required to form substantial concentrations of free chlorine dioxide in solution (i.e., pH higher than about 2) and lower than the pH at which chlorine dioxide is known to disproportionate in solution (i.e., pH below about 12). Preferably, the pH of the resultant solution is between about 4 and 9 to minimize the potential for corrosion of materials with which the solution comes into contact. More preferably the pH of the resultant solution should be in the range of about 5-9, and most preferably in the range of about 6-9; ideally the pH will be 7. In certain cases, it may be advantageous to produce chlorine dioxide in a solution that is already at either a higher or a lower pH than the pH of about 7. Tablets of the present embodiment of this invention may be used to deliver chlorine dioxide into such solutions without materially changing the pH of the solution when the chlorine dioxide concentration is at typical use levels. For example, if a tablet of the present embodiment of this invention is used to produce chlorine dioxide in a typical solution of laundry detergent, it is advantageous for the detergent solution to be at alkaline pH (i.e., >9) where the detergent functions best. Tablets of the present embodiment of this invention may be used for that purpose. In such cases, however, it is preferred that the pH of the resultant detergent/chlorine dioxide solution be below about 12, as chlorine dioxide degrades at a pH higher than about 12.
It is often advantageous for the free halogen concentration of the resultant solution to be low, as free halogen can lead to corrosion of materials in which the solution comes into contact, and free halogen can react with organic materials to produce toxic halogenated hydrocarbons.
In other situations, the presence of a relatively high concentration of chlorine or other free halogen in solution may be acceptable. In such situations, it is possible to use the solid bodies of the present embodiment of this invention to produce very highly converted aqueous solutions of chlorine dioxide where the ratio of the concentration of chlorine dioxide in solution to the sum of the concentrations of chlorine dioxide and chlorite anion is greater than 0.5 on a weight basis. In those cases, the concentration of chlorine or free halogen in solution may be equal to or even greater than the concentration of chlorine dioxide in solution on a weight basis. Suitable surfactants component may be employed herein as well, such surfactants may be cationic, anionic, or non-ionic.
The tablets of the present embodiment of the invention may, if desired, contain optional additional ingredients, that may be useful, for example, to assist in the tableting process, to improve the physical or aesthetic characteristics of the produced tablets and to assist tablet solubilization and/or the yield of chlorine dioxide obtained. Such ingredients include but are not limited to fillers such as attapulgite clay and sodium chloride; tableting and tablet die lubricants; stabilizers; dyes; anti-caking agents; desiccating agents such as calcium chloride and magnesium sulfate; pore forming agents such as a swelling inorganic clay, e.g., Laponite clay available from Southern Clay Products, Inc., and a framework former that can react with one or more other constituents in the formulation to produce a low solubility porous framework structure in which the chlorine dioxide forming reactions may proceed.
Effervescing agents such as sodium bicarbonate may be included in small amounts, e.g., about 1 to about 50 wt. %, based on the weight of the solid body, but these effervescing agents can reduce the conversion of chlorite anion to chlorine dioxide by accelerating breakup and dissolution of the tablet.
The invention includes two general types of tablet devices. One type of device comprises tablets that are fully soluble in water, and the preferred formulation of such tablets comprises particulate powdered technical grade sodium chlorite, and a particulate powdered acid source other than dihydrogen phosphate, preferably sodium bisulfate and a particulate phosphate such as powdered phosphate salt tetra sodium pyrophosphate, tri-sodium phosphate, sodium dihydrogen phosphate, potassium dihydrogen phosphate and others known in the art. Additional phosphates may be supplied external to the tablet making the phosphate present both within and outside the tablet. As an alternative, the tablet may lack the phosphate but be formed of the chlorite and the acid. With this chlorite and acid tablet, the phosphate must be supplied external to the tablet. Additional particulate powdered ingredients may be added to the tablet such as magnesium chloride to even further improve the yield and rate of production of the chlorine dioxide. The particulate powdered ingredients are mixed and the resultant powdered mixture is compressed in a tablet die at a force sufficient to produce a substantially intact tablet, typically about 1,000-10,000 lb./in. 2 .
The resultant tablets are stable during storage as long as the tablets are protected from exposure to water (either liquid or vapor). The tablets rapidly produce a highly converted solution of free chlorine dioxide when immersed in water.
The second type of device comprises tablets that are not fully soluble in water at a high rate. These non-fully soluble tablets are designed to have (or produce) a low solubility or slowly soluble porous framework structure in which the chlorine dioxide forming reactions may proceed to substantial completion prior to dissolution of the porous framework. Generally tablets of this second type convert a greater proportion of their chlorite anion precursor chemical to chlorine dioxide compared to the fully soluble tablets described above.
The preferred formulation for this second type of tablet device comprises particulate powdered sodium chlorite; particulate powdered sodium bisulfate; particulate powdered calcium chloride; and particulate phosphate. Additional phosphate may be supplied external to the tablet wherein the phosphate is present both within and outside the tablet. In another alternative, the tablet will lack the phosphate thus the phosphate must be supplied external to the tablet. A particulate powdered clay such as Laponite clay may optionally be added to even further improve the yield and rate of production of the chlorine dioxide. When utilized in the tablets, the clays are trapped in the pores of the framework and are not released into the bulk solution.
As with tablets of the first type, the particulate powdered ingredients are mixed and the resultant powdered mixture is compressed in a tablet die at a force sufficient to produce a substantially intact tablet, typically about 1,000-10,000 lb./in. 2 . The resultant tablets are stable during storage as long as the tablets are protected from exposure to water (either liquid or vapor). When immersed in water, the tablets rapidly produce a highly converted solution of free chlorine dioxide.
Tablets of this second type generally provide more efficient conversion of chlorite anion to chlorine dioxide compared to tablets of the first type. It is believed that this occurs because the low solubility porous framework provides a favorable environment for the chlorine dioxide forming reactions to proceed until substantial exhaustion of the reactants.
Chlorine dioxide formation in tablets of the second type of device is believed to occur substantially within the favorable environment of the pore space of the low solubility (or slowly soluble) porous framework. Since the favorable pore structure of this framework appears to remain substantially intact during this reaction time, substantially all of the chlorite anion has an opportunity to react and form chlorine dioxide under favorable conditions within the pores. This maximizes chlorite conversion to chlorine dioxide. In contrast, a device of the first type is being dissolved into the bulk solution at the same time that it is producing chlorine dioxide. Since it is believed that the reagents will only react at a practically useful rate under concentrated conditions (such as those that exist within the pores of the tablets), that fraction of the chlorite that dissolves into bulk solution prior to conversion to chlorine dioxide will substantially remain as chlorite and not be converted to chlorine dioxide under the generally dilute conditions of the bulk solution.
The low solubility porous framework of the preferred composition of the second type of tablet device comprises a framework former such as a low solubility compound such as calcium sulfate, calcium phosphate, aluminum phosphate, magnesium phosphate, ferric sulfate, ferric phosphate or zinc phosphate; or a low solubility amorphous material such as silica-alumina gel, silica-magnesia gel, silica-zirconia gel, or silica gel; and may additionally include a clay or other substantially insoluble framework or pore former such as Laponite clay. The calcium sulfate preferably is formed from the reaction between calcium cations e.g., from the calcium chloride constituent and sulfate anions derived from the sodium bisulfate constituent. Other sources of calcium cations such as calcium nitrate as well as other sources of sulfate anions such as magnesium sulfate may also be used. Phosphate anion preferably is provided by use of soluble phosphate compounds such as sodium phosphate, sodium hydrogen phosphate, sodium dihydrogen phosphate, the corresponding potassium phosphate salts, as well as other soluble phosphate salts. The silica alumina gel preferably is formed from the reaction between sodium silicate and aluminum sulfate. Silica-magnesia gel preferably is formed from the reaction between sodium silicate and magnesium sulfate. Silica-zirconia gel preferably is formed from the reaction between sodium silicate and zirconyl sulfate. Silica gel preferably is formed from the reaction between sodium silicate and acidity from the solid acid source. Additional solid acid component may be required to compensate for the alkalinity of the sodium silicate constituent.
The preferred clay, Laponite clay, is insoluble as provided and is not released into the bulk solution. It is a swelling clay that become trapped within the pores, and enhances the pore structure of the porous framework by forming cracks and cavities as it swells. We have found that forming the low solubility porous framework, e.g., the calcium sulfate, calcium phosphate, aluminum phosphate, etc., frameworks in-situ via chemical reaction is particularly advantageous and that the chlorine dioxide yield from tablets wherein the framework is formed in-situ is significantly better (nominally 25% better) than tablets in which the framework material is a constituent of the initial powder formulation. The presence of the clay in addition to the framework material provides only a small improvement over the use of the framework material, without the clay.
The term “low solubility or slowly soluble porous framework” used herein means a porous solid structure that remains substantially undissolved in the product solution during the period of chlorine dioxide production. It is not necessary that the porous framework remain wholly intact during the reaction time to form chlorine dioxide. One aspect of this invention includes tablets of the second type in which the tablet disintegrates into substantially insoluble (or slowly soluble) granules that release chlorine dioxide into solution. This is acceptable, we believe, because the size of the granules is still large relative to the size of the pores within the pore space of the granules, so the necessary concentrated reaction conditions exist within the pore space despite the breakdown of the framework into granules. Typically, the framework former will be present in an amount of about 10 to about 90 wt. %, based on the weight of the solid body.
In tablet devices of both types, it is preferred that the powdered ingredients be dry prior to mixing and tableting in order to minimize premature chemical interaction among the tablet ingredients.
General Procedures for Making and Testing the Tablets of the Present Embodiment of This Invention
Tablet Formation:
The individual chemical components of the tablet formulation are dried prior to use. The desired amount of each component is carefully weighed into a plastic vial. In the following examples, formulations are given on a weight percent basis. The vial containing all the components of the tablet formulation is shaken to mix the components thoroughly. The contents of the vial are emptied into an appropriately sized die (e.g., a 13-mm diameter for a 1 g tablet). The plunger is placed in the die and the contents are pressed into a pellet using a hydraulic laboratory press. The maximum force reading on the press gauge was 2000 pounds unless otherwise noted. This force on the tablet punch may be converted to pounds/in. 2 if the area of the face of the plunger in in. 2 is known (typically 0.206 in. 2 for a 1 g tablet). The resulting tablet is removed from the die and placed in a closed plastic vial until use (typically within 10 minutes).
Tablet Performance:
The tablet is placed in a volumetric flask or container filled with a known amount of tap water. Chlorine dioxide evolution starts immediately as evidenced by bubbles and the appearance of a yellow color. The tablet is allowed to react until completion. Completion of the reaction depends, in part, on the tablet type and size. Typically the reaction time is 2 hours or less if a 1 g tablet is partially insoluble and 0.5 hr. if a 1 g tablet is completely soluble. When reaction is complete, the flask/container is shaken or stirred in order to mix the contents. Then the contents are analyzed. Typically, chlorine dioxide is measured by UV-Vis spectrometry, using four wavelengths (the average value is reported). Chlorite and chlorine are measured by titration of typically 25 ml of chlorine dioxide solution using procedures equivalent to those found in the text, Standard Methods for the Examination of Water and Wastewater, 19 th Edition (1995) pages 4-57 and 4-58. This text is published jointly by the American Public Health Association, The American Water Works Association and the Water Environment Federation. The publication office is American Public Health Association, Washington, D.C. 20005. Total oxidants are measured by titration using a Brinkmann Autotitration System, 716 DMS Titrino equipped with a massive platinum electrode (Brinkmann Part No. 6.0415.100). The method is an iodimetric titration in an acid medium based on the oxidation of iodide to iodine and its subsequent reaction with the titrant, sodium thiosulfate. The typical procedure was as follows. One hundred milliliters of chlorine dioxide solution and a stirring bar were placed in a beaker and 2 g of potassium iodide (Reagent Crystals) and 10 ml of a 1N solution of sulfuric acid (Mallinckrodt) were added with stirring. The resulting solution is titrated with 0.1N thiosulfate solution (Aldrich Chemical Co.). The endpoint is automatically determined by the Brinkmann Titrino software. This endpoint is used to calculate the concentration of total oxidants in the sample. The pH of the original chlorine dioxide solution is measured using a pH electrode either on the solution “as is” and/or diluted with sufficient water to give approximately a 10 ppm concentration of chlorine dioxide.
When using the solid body having particulate sodium chlorite, at least one particulate solid acid source and particulate phosphate, the chlorine dioxide and phosphate liquid mixture is formed by immersing the solid body in water. If, however, the liquid mixture is formed using the solid body having particulate sodium chlorite, at least one particulate solid acid source, and lacking a phosphate the solid body must be immersed in an aqueous phosphate solution to produce the chlorine dioxide and phosphate liquid mixture of the present invention. Such aqueous phosphate solution may be phosphoric acid or sodium dihydrogen phosphate or by adding powdered phosphate salt to water.
Configurations other than the solid bodies discussed immediately above can be used to form the liquid mixture comprising chlorine dioxide and phosphate of the present invention. As briefly described before, the liquid mixture comprising chlorine dioxide and phosphate may be made using all aqueous solutions as well as a combination of aqueous solutions and particulates. The particulates may have different sizes and shapes and need not be disposed in a uniform body. For instance, when forming the liquid mixture using all aqueous solutions, an aqueous sodium chlorite solution may be mixed with a phosphoric acid solution. Another method for forming the liquid mixture uses a combination of aqueous solutions and particulates that are not disposed in a solid body, wherein at least one of the metal chlorite, the acid and the phosphate will be in particulate form.
Another method for producing the liquid mixture comprising chlorine dioxide and phosphate includes using a membrane device. The device is an enclosure that is comprised at least in part by a membrane. Dry chlorine dioxide generating components, such those particulate chlorine dioxide generating components listed above, are disposed and held in the enclosed space of the membrane device. The membrane device is then contacted with water to produce the aqueous chlorine dioxide solution.
The membrane device is water permeable allowing the water into the device to react with the chlorine dioxide generating components. The membrane also permits chlorine dioxide to pass out of the device to form the liquid mixture comprising chlorine dioxide. A full discussion of the membrane device is disclosed in U.S. Pat. No. 6,238,643 and is incorporated by reference herein.
Preparing the chlorine dioxide liquid mixture using the solid body or the membrane device allows for the precise control of the concentration, strength and rate of release of chlorine dioxide.
Chlorine dioxide has established uses in bleaching textiles and pulp in making paper, deodorizing, disinfecting, cleaning, sanitizing and sterilizing surfaces or spaces. The present invention can further be used in wound dressings, environmental cleanup, dental/oral care substances, germ killing material, tooth whitening compositions, and personal lubricants among a variety of other applications.
The ingredients of the liquid mixture comprising chlorine dioxide impart different attributes to the overall mixture. For instance, if the surfactant is a quaternary ammonium compound biocidal activity will be present in the mixture. Surfactant quats, unreacted halogens and chlorine dioxide provide antimicrobial activity to the mixture. Also, surfactants are useful for removing organic soil, which in combination with phosphates can result in reduction of corrosion potential. The phosphate not only reduces the corrosivity of the solution with respect to use on metal surfaces, but also provides cleaning and chelating capacity to the solution. Use of excess acid will help in removing mineral scale from surfaces.
The following examples demonstrate the invention above.
EXAMPLE 1
Tablet formulations were made according to the tables below. Table 1 displays ingredients for a tablet composed of a metal chlorite such as sodium chlorite, a halogen such as sodium salt of dichloroisocyanuric acid, an acid other than hydrogen phosphate being sodium acid sulfate and a phosphate being sodium dihydrogen phosphate. A second tablet composed of a metal chlorite, an acid and a phosphate is disclosed in Table 3.
In both cases, the tablets were prepared using specific desired amount of each ingredient as follows: anhydrous sodium dihydrogen phosphate (>99.0% NaH2PO4) obtained from Sigma-Aldrich Chemical Co., of St. Louis, Mo. was dried at 90 degrees C. It was subsequently determined that drying at 180 degrees C. resulted in improved stability of tablets prior to immersion in water. Other ingredients were dried as described in U.S. Pat. No. 6,699,404. The desired amount of each ingredient was weighed and the ingredients were mixed and pressed into a tablet, and solutions were prepared as described in the above-referenced patent.
The tablet formulations in tables 1 and 3 were tested and data was compiled as to the chlorine dioxide yield, chlorite anion (ClO 2 − ) yield, free oxidant content presence of chlorine and pH level and is displayed in tables 2 and 4, respectively. The resultant solutions were analyzed by potassium iodide/sodium thiosulfate titration following the method given in the “Standard Methods for the Examination of Water and Wastewater”, 19th Ed., 1995, pgs. 4-57 and 4-58, except that the titration was done to a starch indicator endpoint instead of amperometrically.
Generally the metal chlorite is present in the tablets in an amount of about 0.10-40 wt. %, specifically 0.5-30 wt. %, more specifically 15-30 wt. %; acids in an amount of about 35-80 wt. %, specifically 47.50-75 wt. %, more specifically 50-60 wt. %; halogens in the range of about 0.50-10 wt. %, specifically 0-8 wt. %, more specifically 2-5 wt. %; and phosphates in an amount of about 10-60 wt. %, more preferably from 20-50 wt. %. In the resultant mixture, the phosphate is present in an effective amount to promote cleaning being in a range of about 0.1% to 95%, more preferably in a range of about 15% to 95%. Alternatively, the phosphate is present in an effective amount to reduce the corrosivity of the solution. The phosphate is present in the range of about 0.1 ppm to 10%, more preferably in the range of about 1 ppm to 1%.
TABLE 1
Tab-
Component 1
Component 2
Component 3
Component 4
let
A: NaClO 2 %
B: NaDCCA %
C: NaHSO 4 %
D: NaH 2 PO 4 %
1
18.33
0.00
56.67
25.00
2
5.00
0.00
50.00
45.00
3
17.50
0.00
50.00
32.50
4
10.00
3.33
48.33
38.33
5
20.00
0.00
60.00
20.00
6
10.00
3.33
60.00
26.67
7
15.00
0.00
55.00
30.00
8
14.67
4.89
56.00
24.44
9
17.50
0.00
50.00
32.50
10
30.00
0.00
50.00
20.00
11
19.50
6.50
47.50
26.50
12
15.00
5.00
60.00
20.00
13
5.00
1.67
54.58
38.75
14
5.00
0.00
50.00
45.00
15
10.00
0.00
56.67
33.33
16
24.50
8.00
47.50
20.00
17
15.00
5.00
60.00
20.00
18
30.00
0.00
50.00
20.00
19
5.00
0.00
60.00
35.00
20
21.00
7.00
51.83
20.17
21
27.50
5.00
47.50
20.00
22
15.00
5.00
47.50
32.50
23
27.50
5.00
47.50
20.00
24
25.00
0.00
55.00
20.00
TABLE 2
Response 1
Response 2
Response 3
Response 4
Response 5
Tablet
ClO 2 Yield %
ClO 2 -Yield %
Free Oxidant %
Chlorine %
pH
1
2.72
1.41
2.79
0.039
2.97
2
0.65
0.26
0.84
0.101
3.08
3
2.56
3.04
2.97
0.212
3.19
4
0.18
0.02
1.9
0.895
2.85
5
2.4
7.06
2.61
0.108
3.04
6
2.16
0.34
4.96
1.452
2.99
7
1.87
1.93
2.18
0.163
3.08
8
3.61
0.86
5.99
1.231
3
9
1.39
6.71
1.63
0.125
3.03
10
1.9
11.73
2.39
0.253
3
11
5.26
1.45
9.77
2.338
3.48
12
3.6
0.3
8.12
2.346
2.92
13
1.07
0.02
2.24
0.609
2.95
14
0.43
0.16
0.45
0.013
2.93
15
0.99
0.93
1.6
0.32
2.81
16
8.99
1.28
11.28
1.186
3.83
17
3.39
0.64
6.23
1.473
2.74
18
2.29
10.82
2.41
0.063
3.45
19
0.69
0.05
0.47
−0.116
2.93
20
8.71
0.28
9.56
0.441
3.78
21
7.42
5.79
7.29
−0.069
3.45
22
3.75
0.08
8.32
2.372
3.36
23
8.48
2.59
8.85
0.192
4.58
24
2.06
9.66
1.26
−0.415
3.2
TABLE 3
Component 1
Component 2
Component 3
Tablet
A: NaClO2
B: NaHSO4
C: NaH2P04
1
5.00
62.50
32.50
2
5.00
50.00
45.00
3
0.10
75.00
24.90
4
5.00
75.00
20.00
5
0.10
50.90
49.00
6
0.40
58.63
40.97
7
2.55
75.00
22.45
8
0.10
62.95
36.95
9
5.00
50.00
45.00
10
1.17
67.59
31.24
11
5.00
62.50
32.50
12
0.10
50.90
49.00
13
1.17
55.54
43.29
14
5.00
75.00
20.00
15
3.67
58.33
38.00
TABLE 4
Response 1
Response 2
Response 3
Res-
ClO2
ClO2-
Free
Response 4
ponse 5
Run
Yield %
Yield %
Oxidant %
Chlorine %
pH %
1
0.64
0.18
0.67
0.014
2.97
2
0.56
0.06
0.58
0.012
3.1
3
0.02
0.01
0.02
0.003
2.72
4
0.44
0.18
0.64
0.103
2.66
5
0.05
0.01
0.06
0.007
2.99
6
0.05
0.01
0.07
0.014
2.85
7
0.33
0.03
0.38
0.025
2.73
8
0.04
0.003
0.07
0.017
2.78
9
0.73
0.16
0.81
0.044
3.16
10
0.19
0.02
0.21
0.01
2.76
11
0.57
0.22
0.75
0.089
2.85
12
0.03
0.01
0.06
0.015
3.00
13
0.14
0.02
0.15
0.006
2.94
14
0.67
0.03
0.71
0.02
2.70
15
0.38
0.11
0.41
0.016
2.89
EXAMPLE 2
Four sets of solutions were prepared by dissolving a single 1.5 gram size tablet of the formulation of Example 5 of U.S. Pat. No. 6,699,404 in 600 ml of deionized water. To each solution 210 mg of sodium bicarbonate (NaHCO 3 ) was added. 379 mg and 758 mg of sodium dihydrogen phosphate (NaH 2 PO 4 ) were added to the third and fourth solutions, respectively. The third and fourth solutions yielded nominally 500 ppm and 1000 ppm phosphate, respectively.
A corrosion analysis was conducted using test coupons of type 304 stainless steel obtained from Metal Samples Co., Munford, Ala. The corrosiveness of each solution was measured by determining the electrochemical potential necessary to initiate corrosion on each test coupon. The test coupons were attached to a variable DC voltage supply and immersed in the test solutions. A platinum electrode was used for counter electrode. The voltage between the electrodes was slowly increased until the onset of electrical flow. New 304 stainless steel test coupons were used for every test. The voltage at which current flow began is termed “corrosion potential.” A high corrosion potential represents reduced corrosiveness in the test solution.
Table 5 shows the results of the test, showing the average corrosion potential for each phosphate concentration versus the weight ratio of phosphate to chlorine species in the solution. Table 5 is graphed in FIG. 1 and it shows that as the ratio of phosphate to chlorine species increases, the corrosion potential (i.e., less corrosiveness) also increases. Thus, an effective amount of phosphate is used to reduce the corrosivity of the resultant liquid mixture, which consequentially inhibits metal corrosion when applied to metal surfaces. In particular, the corrosion potential improved when the amount of phosphate to chlorine species ratio rose above 0.4.
TABLE 5
Corrosion Potential
Corrosion
Weight Ratio
Potential
Phosphate/Chlorine
(Volts)
0.0
0.602
0.2
0.620
0.4
0.638
0.6
0.645
0.8
0.670
EXAMPLE 3
Different concentrations of phosphate and lauryl sulfate were added to 200 ppm chlorine dioxide solution and corrosion potentials were measured as in Example 2. The data was fitted to a regression equation using a least squares method and FIG. 2 shows the corrosion potentials from that regression equation displayed as contour lines on a graph of the different concentrations of phosphate and lauryl sulfate in the chlorine dioxide solution. According to FIG. 2 , lauryl sulfate had little beneficial effect (i.e., no change in corrosion potential), the surfactant, by itself, had little effect and phosphate alone increased corrosion potential from about 0.6 to about 0.7 volts. However, when the surfactant was combined with phosphate there was much greater positive effect than the sum of the two individual effects. The combination of 1000 ppm lauryl sulfate and 1000 ppm phosphate increased corrosion potential to about 1.2 volts, which is close to the corrosion potential of water.
As stated above, the amount of surfactant needed will depend upon the chlorine dioxide concentration in the solution, the pH, the phosphate type and concentration, and other factors. One of skill in the art could be able to determine an optimum and a minimum necessary concentration of surfactant.
EXAMPLE 4
Tablets were prepared using powdered ingredients dried as shown in Table 5. Specific weights of each dried ingredient as shown in Table 6 were combined in an amber glass jar, the jar was sealed and the powders were mixed by rolling for 1 hour. Tablets were pressed from the powder by placing nominally 1 gram of powder into a 13 mm diameter stainless steel die and compacting the powder with a force of 2000 lb using a hydraulic press.
A tablet weighing 1.06 grams was placed into 1 liter of potable tap water and allowed to react without stirring until fully dissolved. The resultant solution was mixed and analyzed for chlorine dioxide concentration using a Hach DR2010 UV/Visible spectrometer (Hach Company, Loveland Colo.) following the procedure of Hach test method 8138. The concentration was 85 mg/liter.
TABLE 5
Ingredient
Drying temperature, ° C.
Drying Time
Technical grade (80%)
110
Overnight
sodium chlorite
Anhydrous magnesium
300
Overnight
sulfate
Anhydrous sodium
180
Overnight
dihydrogenphosphate
NaDCCA dihydrate
130
Overnight
Anhydrous sodium acid
50/85
Overnight/4 hr
sulfate
TABLE 6
Ingredient
Weight, gm
Technical grade (80%) sodium chlorite
52
Anhydrous magnesium sulfate
42
Anhydrous sodium dihydrogen phosphate
40
NaDCCA
14
Anhydrous sodium acid sulfate
52
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This invention relates to an improved chlorine dioxide solution or liquid mixture containing a phosphate and, as well, as to a composition for forming the chlorine dioxide and phosphate liquid mixture. This improved chlorine dioxide solution is used to clean and/or sanitize without causing corrosion. The corrosion nature of the chlorine dioxide solution is lessened due to the addition of phosphate to the composition.
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BACKGROUND OF THE INVENTION
The present invention relates to a power train which is particularly suitable for use in an amphibious vehicle capable of travel on land and water, and more particularly to a means of adapting a conventional automotive transaxle drive arrangement to drive the wheels and the marine propulsion means of an amphibious vehicle. The invention also relates to an amphibious vehicle having such a power train.
In some automotive power train arrangements the engine has a crankshaft in line with the longitudinal axis of the vehicle, whereby the engine drives an in-line transmission with an integral differential which is typically located between the engine and the transmission, the differential being connected by drive shafts to the drive wheels of the vehicle. This arrangement is commonly known as a transaxle drive and has been employed in front engine, rear engine and mid engine power train layouts.
It is also known for transaxle power train arrangements to be adapted to provide four wheel drive. In such known four wheel drive arrangements, the transaxle will typically drive the front wheels of the vehicle, with a power take off from the transmission driving the rear wheels of the vehicle.
The transaxle drive arrangement is currently used by several large car manufacturers in the production of private passenger vehicles and is therefore produced in relatively high volumes, which makes the arrangement most procurable for use in an amphibious vehicle. In choosing a power train for a specialised low volume production vehicle, such as an amphibious vehicle, availability is an important factor.
EP 0 742 761 discloses a power train for an amphibious vehicle using a front wheel drive power train reversed, to mount the engine behind the rear axle. The marine power take off is by a gearbox taken from the timing end of the engine, opposite to the transmission mounting end. This power take off requires a number of custom designed parts to be designed, built, and assembled; and may require redesign and relocation of engine mounted accessories, such as the alternator drive belt. Also, the reversal of the power train may require additional gearing or other modifications to ensure that the road wheels rotate in the required and expected directions. The cost burdens and assembly requirements of such adaptations are particularly unwelcome to low volume vehicle manufacturers.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a power train for an amphibious vehicle in which a conventional transaxle drive is utilised and adapted to drive at least one pair of road wheels and a marine propulsion means.
According to a first aspect of the invention, there is provided power train for an amphibious vehicle comprising an engine and transaxle drive arranged in North-South alignment, that is with the front or timing end of the engine facing the front of the vehicle and with the engine in longitudinal alignment with the vehicle axis, the transaxle drive including a transmission and differential, the differential being adapted to provide drive to a pair of driven wheels of the vehicle, the power train further comprising a power take off adapted to provide drive to a marine propulsion means.
Preferably, the power take off is provided by means of a drive shaft connectable to an input shaft of the transmission. In a particularly preferred embodiment, the drive shaft is selectively connectable to the input shaft by means of a decoupler which may have means, such as a baulk ring, adapted to synchronize the speeds of the input shaft and the drive shaft as the shafts are coupled. Conveniently, the decoupler may comprise a gear wheel and synchro-mesh unit.
Alternatively, the power take off may comprise a sandwich power take off between the engine and the transaxle, which power take off provides drive to the marine propulsion means. Drive may be transmitted from the sandwich power take off to the marine propulsion unit by means of a prop shaft which may be connected to a drive shaft of the marine propulsion unit by a constant velocity joint.
In one embodiment, each wheel of the pair of the driven wheels is driven by an output shaft of the differential, the arrangement being such that the axis of rotation of the pair of driven wheels is offset along the length of the vehicle from the axis of rotation of the output shafts of the differential. In such an arrangement, drive may be transmitted between each said driven wheel and its respective differential output shaft via a chain or belt drive means. Preferably, the chain or belt drive means comprises a first sprocket mounted to the differential output shaft, a second sprocket mounted to a wheel drive shaft and a belt or chain interconnecting the two sprockets to transmit drive between the output shaft and the wheel drive shaft.
The power take off may provide drive only to the marine propulsion means or may provide drive to a second differential for diving a further pair of road wheels, with the drive to the marine propulsion unit being taken from the second differential. In an alternative arrangement for providing a four wheel drive facility, where the power take off is a sandwich power take off, a further power take off adapted to drive a further pair of wheels of the vehicle may also be provided. Preferably, the further power take off is provided by means of a shaft which is drivingly connectable to the transmission at a rearward end thereof, the shaft being adapted to drive a further differential for driving the further pair of wheels of the vehicle.
In all embodiments of the invention, the power train may be adapted such that the centre lines of the engine, transaxle, and marine propulsion unit are substantially aligned with each other and with the centre line or longitudinal axis of the vehicle.
Preferably, the or each power take off is arranged rearward of the engine.
According to a second aspect of the invention, there is provided an amphibious vehicle having a power train in accordance with the first aspect.
BRIEF DESCRIPTION OF THE DRAWINGS
Several embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 is a plan view of a conventional power train arrangement including a longitudinal engine, and a transmission and differential in a transaxle arrangement for driving the front wheels of a vehicle;
FIG. 2 is a plan view of a conventional power train arrangement including a longitudinal engine, and a transmission and differential in a transaxle arrangement adapted for driving all four wheels of a vehicle;
FIG. 3 is a plan view of a power train for an amphibious vehicle in accordance with the present invention, in which the power train is adapted to drive the rear wheels and the marine propulsion means of an amphibious vehicle;
FIG. 4 shows a schematic section through the transaxle arrangement for driving the rear wheels and marine propulsion means of the amphibious vehicle as shown in FIG. 3 ;
FIG. 5 shows a schematic section through a prior art transaxle where the fifth gear is in a separate compartment to the other four gears;
FIG. 6 Shows a modification to the power train of FIG. 3 , in which the transaxle of FIG. 5 is adapted to provide an alternative power take off arrangement;
FIG. 7 is a plan view of a second embodiment of a power train for an amphibious vehicle in accordance with the invention, in which the power train is adapted to drive the rear wheels and the marine propulsion means of an amphibious vehicle;
FIG. 8 is a plan view of a third embodiment of a power train for an amphibious vehicle in accordance with the invention, in which the power train is adapted to drive the front wheels and the marine propulsion means of an amphibious vehicle;
FIG. 9 is a plan view of a fourth embodiment of a power train for an amphibious vehicle in accordance with the invention, in which the power train is adapted to drive all four wheels and the marine propulsion means of an amphibious vehicle;
FIG. 10 is a plan view of a fifth embodiment of a power train for an amphibious vehicle in accordance with the invention, in which the power train is adapted to drive the front wheels and the marine propulsion means of an amphibious vehicle;
FIG. 11 is a plan view of a sixth embodiment of a power train for an amphibious vehicle in accordance with the invention, in which the power train is adapted to drive the rear wheels and the marine propulsion means of an amphibious vehicle;
FIG. 12 is a plan view of an seventh embodiment of a power train for an amphibious vehicle in accordance with the invention, in which the power train is again adapted to drive the rear wheels and the marine propulsion means of an amphibious vehicle; and
FIG. 13 is a plan view of a eighth and final embodiment of a power train for an amphibious vehicle in accordance with the invention, in which the power train is adapted to drive all four wheels and the marine propulsion means of an amphibious vehicle.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The same reference numerals have been used throughout the drawings to denote common components.
Referring firstly to FIG. 1 , a conventional transaxle drive arrangement, generally indicated at 10 , is shown driving the front wheels 14 , 16 of a vehicle 12 . An engine 18 is conventionally positioned forward of the front wheels 14 , 16 with the crankshaft of the engine 18 in axial alignment with the centre line, chain dotted at 20 , of the vehicle 12 . A transmission 22 is mounted in line with the engine 18 and drives a differential 24 . Drive shafts 26 , 28 drive the front wheels 14 , 16 of the vehicle from the differential 24 . The tear wheels 30 , 32 of the vehicle 12 are not driven.
A second conventional transaxle arrangement 11 for a vehicle 13 will now be described with reference to FIG. 2 . Engine 18 , transmission 22 , and differential 24 are arranged to drive front wheels 14 , 16 through drive shafts 26 , 28 as in the arrangement of FIG. 1 . In this case, however, a power take off is located at the rear of transmission 22 , driving centre differential 31 and rear differential 33 . Drive shafts 27 and 29 drive rear wheels 30 and 32 respectively. This arrangement is a convenient way of offering a four wheel drive transmission in combination with a “North-South” mounted engine and transaxle as shown.
The term “North-South” will be understood by those skilled in the art to indicate a vehicle power train in which the engine is mounted so that the axis of the crankshaft is in alignment with or parallel to the axis of the vehicle and in which the front end of the engine, usually the timing end, faces towards the front of the vehicle. The term should be interpreted in this sense throughout the description and/or claims.
A first embodiment of the invention will now be described with reference to FIGS. 3 and 4 . A North-South mounted engine 18 and in line transmission 22 are positioned at the rear of an amphibious vehicle 34 , with the crankshaft of the engine 18 in axial alignment with the axis 20 of the vehicle 34 and the front or timing end of the engine facing towards the front of the vehicle. The engine 18 is positioned forward of the centre line of the rear wheels 30 , 32 , and the transmission 22 drives a differential 24 in a transaxle arrangement, as described with reference to FIG. 1 . Drive shafts 26 , 28 drive the rear-wheels 30 , 32 of the vehicle 34 from the differential 24 .
Decouplers 43 , 45 are provided in the drive line between the differential 24 and the driven road wheels 14 , 16 . The decouplers 43 , 45 enable drive to the driven wheels to be decoupled when the vehicle is operated in marine mode. Alternatively, rather than providing a decoupler 43 , 45 in the drive line between the differential and each driven wheel, a decoupler may be provided in the drive line between the transaxle and only one of the driven wheels 14 , 16 or they may be omitted altogether.
As is best seen in FIG. 4 , a power take off is provided on the transmission to drive a marine propulsion means in the form of a water jet 40 . An impeller shaft 36 drives an impeller 38 of the water jet 40 from the transmission 22 . The impeller shaft 36 can be selectively coupled to an extension of the input shaft 44 of the transmission by a decoupler 42 . Gears 46 mounted to the shaft 44 are engaged in known manner with corresponding gears 48 mounted on an output shaft 50 , which drives the differential 24 . The gears 46 and corresponding gears 48 provide the gear ratios of the transmission 22 .
In a preferred embodiment the decoupler 42 which selectively couples the input shaft 44 of the transmission to the impeller drive shaft 36 has means which are adapted to synchronise the speeds of the shafts as they are coupled. For example, the decoupler may be of the type disclosed in the applicants co-pending International patent application PCT/GB01/03493 which comprises a baulk ring for synchronizing the speeds of the shafts.
A modification to the first embodiment will now be described in relation to FIGS. 5 and 6 .
FIG. 5 shows a conventional transaxle 22 ′ in which a fifth speed is provided by an ‘overhung’ pair of constant mesh gears 58 , 60 which are positioned in a separate compartment 61 , adjacent to the main compartment 63 of the transaxle 22 ′. A synchro-mesh unit 65 is employed to couple the drive gear 58 to the input shaft 44 whereby the drive gear 58 and the driven gear 60 may drive the output shaft 50 and thus the differential 24 . Similar synchro-mesh units (not shown) are conveniently employed to couple and decouple the gears 46 and 48 in the main compartment 63 .
FIG. 6 shows how the transaxle 22 ′ of FIG. 5 can be modified to provide a power take off for use in the power train of FIG. 3 . In the modified transaxle 22 ″ the driven gear 60 has been removed from the output shaft 50 whereby the fifth speed of the transaxle 22 ′ will no longer be available to drive the rear wheels 30 , 32 of the vehicle 34 . However, the drive gear 58 may still be coupled to the input shaft 44 by the synchro-mesh unit 65 , such that by coupling the fifth gear axially to the impeller shaft drive shaft 36 , as shown at 67 , drive to the water jet 40 may be provided in a manner similar to that described above in relation to FIG. 4 , with the synchro-mesh unit 65 acting as a decoupler.
This modified arrangement provides an advantage over the arrangement of FIG. 4 , in that the existing coupling system of synchro-mesh unit 65 may be employed as a decoupler in place of the additional decoupler 42 used in FIG. 4 .
The modified power take off arrangement can of course be used with any transaxle in which a pair of overhung gears are located in a separate compartment of the transaxle. For example where the transaxle has a sixth speed gear in a separate compartment, the sixth speed gear can be used to provide the power take off as described above.
Whilst preferred forms of the power take off have been described, it will be understood by those skilled in the art that any suitable form of power take off can be used to drive the water jet 40 from the transmission.
FIG. 7 shows a second embodiment of the invention. The arrangement is similar to that of the first embodiment except that the engine 18 and transmission 22 have been moved forward in the vehicle to accommodate a longer jet drive 41 . The differential 24 has output drive shafts 26 , 28 on which are mounted sprockets 21 , 23 . The sprockets 21 , 23 drive corresponding sprockets 21 ′, 23 ′ on offset wheel drive shafts 26 ′, 28 ′ by means of a belt or chain 47 , 47 ′. This arrangement permits drive to be transmitted between the differential 24 and the driven wheels 30 , 32 whose axis of rotation is offset along the length of the vehicle from the axis of rotation of the output shafts 26 , 28 of the differential.
A decoupler 43 , 45 is fitted in the drive line between the differential and each of the driven rear wheels 30 , 32 in order that drive to the wheels can be disconnected when the vehicle is used in a marine mode. In the present embodiment a decoupler 43 , 45 is fitted in each of the wheel drive shafts 26 ′, 28 ′ but it will be appreciated that the decouplers could be fitted in the differential output shafts 26 , 28 instead. Alternatively only a single decoupler can be used in the drive path between the differential and one of the wheels. Where a single decoupler is used to disconnect drive between the differential and one of the driven wheels 30 , 32 , the corresponding wheel pinion in differential 24 will spin without transmitting power, while the other pinion will not be driven. If it is found in practice that the other wheel drive shaft rotates, through transmission oil drag or whatever other reason, it may be locked by use of the vehicle handbrake.
In a third embodiment of the invention, shown in FIG. 8 , the engine 18 of an amphibious vehicle 54 is mounted in the conventional position for a transaxle front wheel drive arrangement, that is forward of the centre line of the front wheels 14 , 16 . The front wheels 14 , 16 are driven by drive shafts 26 , 28 with at least one decoupler 43 , 45 as described with reference to FIG. 3 . A propeller shaft 52 is connected to a decoupler 42 , which is driven by the conventional input drive shaft 44 of the transmission 22 . The propeller shaft 52 is coupled to the input shaft by means of the decoupler 42 in a manner similar to way in which the impeller shaft 36 is connected to the input shaft in the FIG. 4 embodiment. Alternatively, the propeller shaft 52 may connected to the input shaft by use of a fifth or sixth speed gear and synchro-mesh unit as described above in relation to FIGS. 5 and 6 . The propeller shaft 52 runs axially of the vehicle 54 and is connected to the impeller shaft 36 by means of a constant velocity joint 56 . The impeller shaft 36 drives the impeller 38 of the water jet 40 , positioned at the rear of the vehicle 54 .
FIG. 9 shows a fourth embodiment of the invention, with all four road wheels of the vehicle 64 driven as well as a marine drive 40 . It should be noted that in this embodiment, the jet drive may be geared down or up according to the gear ratios of the transmission 22 ; whereas in the embodiments of FIGS. 4 and 6 , the jet is driven at crankshaft speed. This embodiment generally follows the road car layout of FIG. 2 , but incorporates at least one decoupler 43 , 45 for the front wheel drive shafts 26 , 28 , and at least one decoupler 43 ′, 45 ′, for rear wheel drive shafts 27 , 29 . In this case, rear differential 33 ′ incorporates a power take off to take drive rearwards to decoupler 42 and marine drive 40 . It is not proposed to describe such a power take off in detail, because they are known in the power train art, for example for transmitting drive from the second to the third axle of a 6×6 truck. It is advantageous to use independent rear suspension with this layout, as this will allow differential 33 ′ to maintain a consistent position relative to water jet 40 . This in turn avoids any need for articulation of rearward drive shaft 25 ′, which would be difficult to arrange satisfactorily in the short shaft length available.
FIG. 10 shows a fifth embodiment of the invention, with front road wheels of the vehicle 74 driven as in the FIG. 8 embodiment, but with an alternative power take off device. Engine 18 is offset forward compared to the FIG. 8 embodiment, and a sandwich type power take off 53 is interposed between the engine and the transaxle. Sandwich power take off 53 will not be described in detail in the present application but may be constructed according to the applicant's co-pending British patent Application No. GB 0020884.3. The power take off 53 drives a propeller shaft 62 , which is necessarily installed at a lateral angle to the vehicle centre line 20 . A constant velocity joint 56 is fitted, to align the input drive of the water jet unit 40 with its output. Decoupler 42 may be fitted in the propeller shaft to enable the water jet drive to be disengaged during road driving. A further constant velocity joint (not shown) may be fitted at the front of the propeller shaft 62 , adjacent to power take off 53 . The further constant velocity joint may be combined with a decoupler, according to the applicant's co-pending International patent application No. PCT/GB01/03493, in which case the separate decoupler 42 can be omitted.
FIG. 11 shows a sixth embodiment of the invention. This embodiment is similar to the first embodiment shown in FIG. 3 , except that drive to the marine propulsion unit 40 is provided from a sandwich power take off 53 between the engine 18 and the transaxle. The sandwich power take off unit 53 is the same as that described above in respect of the fifth embodiment as shown in FIG. 10 . Use of a sandwich power take off has the advantage that decoupler(s) are not required in the wheel drive shafts 26 , 28 , because the gearbox, whether manual or automatic, can be left in neutral gear when driving in marine mode. The sandwich power take off 53 drives the marine propulsion unit 40 by means of a prop shaft 62 ′ which is connected to a drive shaft 36 of the marine propulsion unit by a constant velocity (CV) joint 56 because of the angle of shaft 62 ′. A second CV joint will be required adjacent to the power take off. This may be combined with a decoupler 42 shown in FIG. 11 . It will be noted here that drive shaft 36 is of vestigial length, for packaging reasons.
FIG. 12 shows a seventh embodiment of the invention, where the sandwich power take off arrangement described in relation to FIGS. 10 and 11 is applied to the power train layout of the second embodiment of the invention, as shown in FIG. 7 .
FIG. 13 shows an eighth and final embodiment of the invention, where the sandwich power take off arrangement as shown in FIGS. 10 to 12 is applied to the power train layout of the fourth embodiment of the invention, as shown in FIG. 9 . This layout is particularly advantageous in that it avoids the use of either two or four wheel drive shaft decouplers.
In each of the sandwich power take off embodiments described above in relation to FIGS. 10 to 13 , a decoupler 42 is provided in the prop shaft adjacent to the power take off, and a CV joint 56 is incorporated in the marine propulsion unit. This is a preferred solution, because of control cable packaging; but it will be appreciated that the positions of CV joint and decoupler could be reversed if it is more convenient.
Whereas the invention has been described in relation to what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not limited to the disclosed arrangements but rather is intended to cover various modifications and equivalent constructions included within the spirit and scope of the invention. For example, whilst it is preferred that the marine propulsion unit should be in the form of a water jet, any suitable marine propulsion means, such as a marine screw propeller, could be used.
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A power train for an amphibious vehicle includes an engine and transaxle arranged North-South, driving front, rear, or all four road wheels. A power take off with optional decoupler and constant velocity joint drives marine drive. The power take off may be taken from the input shaft of the transmission, and may use a synchronizer. The transaxle includes a differential. The rear wheels may be set back from the differential outputs, with intermediate drives by chains or belts. A sandwich type power take off may also be used. In the four wheel drive embodiment, a power take off is required from the rear differential. Decouplers may be provided in at least one wheel drive shaft on each driven axle.
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BACKGROUND OF THE INVENTION
This invention relates to gas cooled nuclear reactors and is concerned more particularly with the construction of a coolant filter for the removal from the coolant gas of certain fission products.
The filter of the present invention is for the purpose of removing certain fission products, in particular cesium 137 from the coolant gas. As will be apparent from the following description, it will more generally serve as a filter for those radio-active species of molecular or atomic size which are absorbed by graphite at a high temperature. These include, in addition to cesium 137, strontium 90 and silver 110m.
Cesium metal release is dependent on the coolant channel surface temperature in the reactor core. The problem of cesium release therefore arises particularly with high temperature reactors. Removal of cesium from the coolant gases enables a designer to use a higher temperature and/or, provided the cesium is removed before the coolant is passed through energy extracting means to reduce the gamma exposure rate in the energy extracting means. The term "energy extracting means" used herein includes a heat exchanger and/or a turbine.
SUMMARY OF THE INVENTION
According to this invention, a filter for the coolant gas of a gas cooled nuclear reactor comprises a graphite body having holes therein with a hydraulic diameter greater than 1 mm and less than 6 mm and having a ratio of length to equivalent hydraulic diameter greater than 170 and less than 1000. The holes may be of any cross-section, and may for example be annuli. The hydraulic diameter of the hole is the ratio of four times the cross-sectional area of the hole to the wetted perimeter of the hole and is equal to the actual diameter in the case of a circular hole.
This filter is preferably situated at the outlet of the coolant from the core of a gas cooled reactor and is operated at the core exit coolant temperature. Thus, unlike conventional filters which are operated at the low temperature of the core inlet coolant gases which have passed through the energy extracting means the filter of the present invention substantially reduces activity levels in the coolant circuit, thereby facilitating inspection and repair of the energy extracting means and other out-of-core components.
With such a filter, fission products such as cesium 137 are deposited on and diffuse into the graphite of the filter. The rate of diffusion is dependent on the temperature of the graphite. It may be shown that the quantity held by the filter is a function of the temperature.
Since the filter can be situated immediately at the outlet of the core and so acquire substantially the temperature of the gas leaving the core, the gas is not cooled in passing through the filter.
In high temperature gas cooled reactors, it is the present practice to have vertical channels through the core through which the coolant passes. At the two ends of the core, graphite reflector blocks are provided and very conveniently the filter of the present invention is used in place of the graphite reflector block at the outlet end of the core, the block serving both as a conventional reflector and also as the filter. This filter however differs from conventional reflector blocks in that the channels for the coolant gas have the dimensions defined above and are therefore of very much smaller cross-section than the coolant channels such as have heretofore been provided through conventional reflector blocks.
The invention thus includes within its scope a gas cooled nuclear reactor having a core through which a coolant gas is passed and having a filter as described above situated at the gas outlet end of the core for filtering the coolant.
Thus according to another aspect of the invention, in a gas cooled nuclear reactor having a core assembly through which a coolant gas is passed and energy extracting means for extracting energy from said gas, there is provided a filter arranged so that the gas from the core passes through the filter before passing to said energy extracting means, which filter comprises a graphite body having holes therein with a hydraulic diameter between 0.001 and 0.006 meter and a ratio of length to hydraulic diameter between 170 and 1000.
It is impossible to construct a body filter as described above from individual blocks assembled in series and/or in parallel. It is readily possible to pass the whole of the coolant flow from the core through such an array of filters.
Because the passages through the filter blocks are smaller than the passages through the core, they will normally be made much more numerous so that the required coolant flow can be obtained without any substantial pressure drop. Thus, in a reactor, means may be provided at the interface between the core outlet and the filter block for the gas to pass from the core outlet into the various passages through the filter. For this purpose provision may be made for the gas to pass across the end face of the filter block. This may be done for example by providing a pattern of slots across the inlet face of the filter block or by spacing the filter block slightly away from the end of the core, for example by forming a land around the periphery of the filter block. Preferably, the dimensions of such slots or said land are sufficient to provide a greater hydraulic diameter than that of the holes in the filter block to avoid unnecessary pressure drop but, as explained above this hole diameter is between 1 and 6 mm and it is readily possible to mill slots of the required depth in the face of the graphite filter.
In a typical filter block, holes of 1.5 mm radius are employed, the filter being 1 m long and having a fractional free flow area greater than 0.227. Such a filter will give a decontamination factor of more than 10 for cesium 137. The decontamination factor is the ratio of the concentrations of the material under consideration e.g. cesium 137, in the coolant at the inlet and the outlet.
In a reactor in which the coolant flows downwardly through the core, the filter will be situated beneath the core and can form the core support.
If a cesium filter is to be effective, it must be able to retain any cesium it removes until it can be changed. The filter of the present invention may be incorporated as part of the fuel block structure in a reactor of the kind in which the fuel is incorporated in carbon blocks. In this case it may typically be changed after approximately three years. Alternatively the filter may remain in the core for the reactor lifetime. The retention of the cesium in the graphite depends on the effective diffusion coefficient for cesium. In practice the cesium deposited on the surface of the filter channel will quickly disperse and will be substantially uniformly distributed throughout the ligaments between the channels. The amount of cesium the filter can hold is a function of temperature. The capacity of the filter will vary markedly for different elements depending on the isotherm constant for adsorption of the element on graphite. Qualitatively, the capacity of the filter in mass units will be higher for strontium than for cesium and lower for silver than for cesium.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram illustrating part of a gascooled nuclear reactor embodying the invention;
FIG. 2 is a plan view of part of a filter block for use in the embodiment of FIG. 1;
FIG. 3 shows a possible arrangement of the filter block beneath a fuel block;
FIG. 4 is a plan view of part of another form of filter block;
FIG. 5 is a part section along the line 5-5 of FIG. 4; and
FIGS. 6, 7 and 8 are graphical diagrams.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates diagrammatically part of a helium-cooled high temperature reactor operating at about 800° C reactor exit coolant temperature. The reactor core 10 shown diagrammatically in FIG. 1 comprises stacks of graphite blocks having vertically aligned coolant channels and having fuel pins within such channels or having fuel material incorporated in the graphite blocks. At the top and bottom ends of the core are graphite reflectors. In this reactor, the flow is downwards. The upper reflector comprises graphite blocks 11 with coolant passages. The lower reflector is formed by a graphite filter 12 which will be further described below.
The coolant gas enters through an inlet 13 into a header 14 above the top reflector and passes downwardly through the top reflector, the core 10 and the filter 12 to a further header 15 from whence it leaves via an outlet 16 to energy extracting means in the form of a steam raising boiler 17, or other heat exchanger and/or turbine, and is then recirculated to inlet 13 by pump 18. The present invention is concerned primarily with the filter 12 and no further description will be given of the reactor core which would, in the known way have suitable controls and would have side reflectors and be contained within a shield. Likewise, the boiler 17 and circulating pump 18 may be of known construction.
The graphite filter 12 is typically 1 meter high and has a plurality of vertical channels through it, formed by straight cylindrical holes typically of 3 mm diameter. The filter 12 may be formed of a number of separate graphite blocks arranged side by side and/or stacked. Its upper surface is milled to have a number of slots extending across it so as to permit of sideways flow of the coolant leaving the core channels so that the coolant is dispersed to flow through the more numerous filter channels. These slots thus constitute header means between the core channels and filter channels. The slots further give some protection against blocking of the filter channels by any particulate material dropping through the core channels.
Referring to FIG. 2, which is a plan view of part of the top of the filter 12, the holes are shown as cylindrical holes 19 or radius r and wall thickness 2t. The ratio of r to t may vary over wide limits. If r is equal to t, the free flow area of the filter structure is 0.227 of the total area of the structure. The pressure drop may be reduced by increasing the free flow area that is to say increasing the ratio of r to t.
FIG. 3 shows part of a filter below fuel blocks. In this particular embodiment, the core comprises blocks 20 having fuel elements 21 embedded therein and coolant channels 22. Below the core is an array of filter blocks 23 each having coolant channels 24 with a plurality of channels 24 for each coolant channel 22 in the core. The tops of the top filter blocks of the array are milled to leave a land 25 around a header region 26. FIG. 3 also shows a handling hole 27 extending through the core and filter assembly.
Instead of having a land around the periphery of the filter 12 or around regions of the top surface of the filter 12, the header can be formed as shown in FIGS. 4 and 5 by a pattern of slots 30 milled across the top of the filter to leave, in this example, triangular lands 31.
The attenuation of concentration of cesium down a long straight cylindrical pipe for infinite sing behaviour at the walls is given by, ##EQU1## where C is the concentration of cesium at x,
C o is the concentration of cesium at x=0,
k is the mass transfer coefficient for cesium,
x is the distance down the pipe,
r is the radius of the pipe,
v is the velocity of the coolant along the pipe.
The decontamination factor is given by: ##EQU2##
If it is assumed that the whole of the bottom of the core is covered by a structure as shown in FIG. 2, the velocity v of the coolant in the pipes is given by: ##EQU3## where M is the total coolant mass flow,
R is the radius of the core,
ρ is the density of the coolant at core exit temperature,
f is the fractional free flow area of the filter structure, given by: ##EQU4## with r and t as shown in FIG. 2. Three values of f will be used later equivalent to the following conditions:
______________________________________ r=t, f=.227 r=1.5t, f=.326 r=2.0t, f=.403______________________________________ -
and also as a limiting condition f=1.
The Reynolds number for the coolant flowing through one of these pipes is given by: ##EQU5## where μ is the viscosity of the coolant. This expression has been evaluated for a range of values of f and r and is plotted in FIG. 6 which is a graph of Reynolds number Re as a function of radius r (in meter) and fractional free flow area f. For the majority of values of f and r of interest the flow down the pipes is turbulent.
For turbulent flow, by analogy with heat transfer, the mass transfer coefficient k can be represented by: ##EQU6## where D is the diffusion coefficient of cesium in the coolant, Sc is the Schmidt number for cesium in the coolant. ##EQU7##
Substituting in (2) we have ##EQU8## This expression has been evaluated for a range of values of r and f using the parameter values listed in Table 1. The results are shown in FIG. 7, which is a graph of decontamination factor as a function of r and f.
Table 1__________________________________________________________________________ Total core mass flow M 700 kg.s.sup.- .sup.1 Core radius R 3.75 m Length of filter structure x 1 m*Diffusion coefficient of cesium in helium D 5×10.sup.-.sup.6 m.sup.2 s.sup.-.sup.1*Density of helium p 2.46 kg.m.sup.-.sup.3*Viscosity of helium μ 4.85×10.sup.-.sup.5 kg.m.sup.-.sup.1.s.sup.- .sup.1__________________________________________________________________________ *These values were evaluated at a pressure of 55 b and a temperature of 800° C.
The pressure drop associated with the filter will have three components. Inlet pressure drop, outlet pressure drop and friction loss down the pipes.
The friction loss down a pipe is given by: ##EQU9## where Δp is the pressure drop along pipe length x, c is the coefficient of skin friction.
It can be seen from FIG. 6 that for the majority of values of r and f of interest the flow down the pipes is turbulent. The value of the skin friction coefficient c, depends on the surface roughness and Reynolds number, a value for c of .01 will be assumed for the following calculations. This value is slightly higher than that suggested for very rough pipes and as such is pessimistic.
Rewriting (9) we have: ##EQU10##
This expression has been evaluated for a range of values of r and f, and is plotted in FIG. 8 which is a graph of Δp as a function of r for different values of f.
Inlet and outlet pressure drops may be estimated from the velocity of the coolant and the fractional free flow areas using:
Δp(inlet) = 1/4ρv.sup.2.sub. (inlet) (1-f)
Δp(outlet) = 1/2ρv.sup.2.sub. (outlet) (1-f).sup.2
where
v.sub.(inlet) is the velocity of the coolant before entering the filter,
v.sub.(outlet) is the velocity of the coolant before leaving the filter.
Values of Δp inlet and outlet are given in table 2.
Table 2______________________________________ f .227 .326 .403______________________________________Δp inlet (mb) .20 .17 .15Δp outlet (mb) 5.9 2.2 1.1______________________________________
If a cesium filter is to be effective it must be able to retain any cesium it removes until it can be changed. Two possibilities exist, one that the filter is incorporated as part of the fuel block structure and is changed after approximately three years, the other, that the filter remains in the core for the reactor lifetime of approximately 30 years.
The effective diffusion coefficient Dg for cesium in graphite is given by ##EQU11## (in the concentration range 0-30 μg/g) where, T is the temperature of the graphite ° K. from which the diffusion coefficient at 800° C is:
4.37 × 10.sup..sup.-11 m.sup.2.s.sup..sup.-1
Using this figure it is possible to calculate the random walk distance
x = √ Dt
for times of 3 and 30 years.
x(3 years) = 6.4 × 10.sup..sup.-2 m
x(30 years) = 2.0 × 10.sup..sup.-1 m.
Since the size of ligaments considered is from .003 to .03 m it can be assumed that any cesium deposited on the surface of the filter channels will quickly disperse uniformly across the ligaments.
A release rate for cesium-137 of 10 Ci.yr.sup. -1 is equivalent to an average gas concentration of 2.3 × 10 7 atoms.g.sup. -1 or an equilibrium cesium on graphite concentration of 3.8 μg/g.
The total mass of graphite in the filter structure is
π R.sup.2 1(1-f)ρ .sub.(graphite)
or approximately 40,000 kg.
The filter is therefore capable of holding 152 g of cesium or 13 k Ci of cesium-137 compared with a release rate of 10 ci.yr.sup. -1 for 30 years, or 300 Ci.
The amount of cesium the filter can hold is a function of temperature, a reduction of the temperature by 50° C is worth a factor of 15 on the equilibrium cesium burden on the reflector.
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In a gas cooled nuclear reactor, cesium metal release into the coolant gas is dependent on the coolant channel surface temperature in the core. The present invention relates to a filter for removing cesium from the coolant gas before it passes to the heat exchanger. The filter comprises a block or blocks of graphite having holes therein with a hydraulic diameter between 1 mm and 6 mm and a ratio of length to equivalent hydraulic diameter between 170 and 1000. This filter is arranged at one end of the reactor core so that the gases pass straight from the core into the filter block.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention pertains to a concise air diffuser system particularly suitable for use with medical thermal blankets wherein the temperature of forced air is controlled by passing the air over a heat exchanger.
2. Description of the Related Art
In the assignee's U.S. Pat. No. 5,125,238 and the assignee's U.S. Pat. No. 5,300,098, a medical thermal blanket, and controls, are disclosed wherein temperature controlled air, usually heated air, is forced into an inflatable blanket having a plurality of orifices whereby the heated air impinges upon a patient to maintain or increase body temperature. Such blankets are often used in post surgery and trauma situations.
Because of the nature of a medical thermal blanket, i.e. the apparatus must be of concise configuration as to be readily portable as placed bedside, the space available for heating the air prior to introduction into the blanket is limited, and it is necessary to effectively transfer heat from air forced by a fan into a heat exchanger containing plenum. The heat exchanger, of the heating type, is of the electrical resistance format, and in order to provide maximum heat exchanger life it is important that a uniform flow of forced air pass over the heat exchanger to prevent localized hot or cold spots on the heat exchanger, efficiently transfer the heat from the heat exchanger to the air, and provide a uniformly heated air to the blanket. Also, in order to provide accurate temperatue control, the temperature of the air flowing over the thermal sensor downstream of the heat exchanger must be substantially equivalent to the uniformly heated air supplied to the blanket.
Diffusers for heated air often take the form of louvers or vanes, such as shown in U.S. Pat. Nos. 1,879,152; 2,241,753; 2,699,323 and 4,176,709. However, conventional air diffusers used in conjunction with heat exchangers of the aforementioned type are not suitable for use with concisely related heat exchangers employing a closed plenum, and prior to the advent of the instant invention an efficient and concise air/heat exchanger system using an air diffuser has not been available.
OBJECTS OF THE INVENTION
It is an object of the invention to provide a concise diffuser system for use with a medical thermal blanket wherein air forced into a plenum containing a heat exchanger and thermal sensor is uniformly distributed over the heat exchanger and sensor with a minimum loss of pressure and a minimum of resistance to air flow.
A further object of the invention is to provide an air diffuser system for use with a medical thermal blanket wherein the diffuser requires no moving parts, quietly diffuses the air evenly over the heat exchanger and thermal sensor, and is of an economical manufacture.
Yet another object of the invention is to provide a diffuser system for a medical thermal blanket utilizing an elongated heat exchanger wherein the diffuser distributes the air in an elongated pattern along the length of the heat exchanger to assure uniform heat exchanging characteristics and prevent localized excessive heating or cooling heat exchanger problems.
An additional object of the invention is to provide a concise diffuser system for use with a medical thermal blanket wherein a heat exchanger is located within a plenumand a thermal temperature sensor is located downstream from the heat exchanger wherein an accurate air temperature measurement at the location of the thermal sensor represents the air temperature downstream of the heat exchanger which is supplied to the blanket.
SUMMARY OF THE INVENTION
A medical blanket system using the diffuser system of the invention receives temperature controlled air pressurized by a fan. Usually, the pressurized air is heated by an electrically operated heat exchanger wherein the pressurized air supplied to the blanket has been heated to a pre-determined temperature. The fan is located within a housing, and a heat exchanger plenum is located within the housing and receives the pressurized air supplied by the fan. The heat exchanger is located within the plenum, and the plenum includes an outlet communicating with the blanket through a flexible hose.
The heat exchanger is of an elongated configuration using a plurality of fins heated by the heat exchanger core, and air discharged from the fan passes over the heat exchanger and fins absorbing heat therefrom for discharge from the plenum to supply the blanket. The diffuser .system of the invention is located adjacent the plenum pressurized air inlet whereby the air entering the plenum immediately engages the diffuser and is spread over the heat exchanger length in such a manner as to eliminate localized hot or cold "spots" on and downstream of the heat exchanger resulting in a substantially uniformly heated air which passes across the thermal sensor and through the plenum outlet to the blanket supply hose.
The diffuser system consists of a pair of arc or crescent shaped openings defined by a planar diffuser base and a deflector bent from the base. The resulting diffuser opening is of a somewhat elongated configuration having a greater dimension at the central region of the opening than at the opening ends. The angle of the diffuser, and its location, with respect to the plenum inlet results in a substantially uniform flow of air over the length of the heat exchanger resulting in an efficient transfer of heat to the air. The construction of the diffuser system provides highly efficient and effective air diffusion in a concise configuration.
The diffuser system also includes vent holes whereby a portion of the pressurized air passes over the end regions of the heat exchanger to prevent overheating thereof.
The diffuser is economically formed by a sheet metal stamping and bending processes, and may be readily fabricated using known manufacturing techniques.
BRIEF DESCRIPTION OF THE DRAWINGS
The aforementioned objects and advantages of the invention will be appreciated from the following description and accompanying drawings wherein:
FIG. 1 is an elevational sectional view through the control housing for a thermal medical blanket illustrating the heat exchanger plenum therein,
FIG. 2 is an enlarged elevational view, partially sectioned, illustrating the fan and heat exchanger plenum,
FIG. 3 is a plan view of the plenum and diffuser, the heat exchanger being eliminated for purpose of illustration,
FIG. 4 is a view of the diffuser blank after the openings have been stamped, and prior to bending of the blank lateral regions,
FIG. 5 is an elevational end view of the diffuser as taken along Section 5--5 of FIG. 3, and
FIG. 6 is a sectional view through the diffuser as taken along Section 6--6 of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIG. 1, a thermal medical blanket is illustrated at 10 which will be of the general type shown in the assignee's U.S. Pat. No. 5,125,238. The blanket 10 is inflatable by forced air and is placed over the patient's body and includes openings whereby the temperature controlled air within the blanket is directed over the patient. The air inflating the blanket 10 is provided through a flexible supply hose 12 shown in dotted lines. The blanket system includes a housing 14 upon which the controls are located, and the housing 14 internally includes a centrifugal fan 16 powered by an electric motor 18. A plenum 20 is located within the housing 14 defining a separate chamber therein, and the hose fitting 22 is exteriorly mounted upon the upper region of the housing 14 for connection with the hose 12. An electric heat exchanger 24 is located within the plenum 20, and a mounting plate 26 may be used to mount the plenum upon the outlet of the fan 16. The plenum 20 includes an inlet 28 communicating with the outlet of fan 16, and the plenum 20 also includes an outlet 30 which is in direct communication with the hose fitting 22 as will be appreciated from FIG. 2. A thermal sensor 25 is mounted in the plenum 20 downstream of heat exchanger 24 between the heat exchanger 24 and hose fitting 22 to permit control of the heating circuit as explained in U.S. Pat. No. 5,300,098.
The heat exchanger 24 is of an elongated configuration and is preferably of the electric resistance type having a plurality of plates 32 mounted thereon constituting fins which are in a heat conducting relationship to the heat exchanger core, and are surrounded by air within the plenum 20. The end regions of the heater are represented at 34 and 36, respectively, the end 34 constituting a hairpin type 180° turn. The heat exchanger 24 is of a conventional commercial type and its construction, per se, constitutes no inventive aspect to the present invention.
The diffuser 38 is located within the plenum 20 adjacent the plenum inlet 28. The diffuser 38 may have mounting tabs extending through the plenum and may be bolted to the mounting plate 26.
The diffuser 38 is of a sheet metal construction and is preferably formed of a flat sheet metal blank, FIG. 4, the sheet metal blank basically consisting of a base 40 of a planar configuration. The blank includes an upper edge 42 and a lower edge 44, and lateral edges 46. The blank includes lateral regions 48 adjacent the edges 46, and vent holes 50 are formed in the lateral regions 48.
The primary air flow through the diffuser 38 is through the openings 52, two of which exist, and are of identical configuration. The openings 52 each include an outer circular arc 54 and an inner circular arc 56 wherein portions 58 are formed in the diffuser blank adjacent the arcs 56.
The portions 58 constitute deflectors as the portions 58 are bent inwardly approximately 40° with respect to the plane of the base 40, FIG. 6, and the deflectors 58 each define an opening 52 by the associated arcs 54 and 56. Accordingly, the openings 52 are of a maximum area at their central region, and at a minimum area where the arcs 54 and 56 intersect. In a commercial embodiment of the invention, the radius of the arcs 56 is 1.320 inches, while the radius of the opening arcs 54 is 1.188 inches, and the greater radius of the arcs 56 permits a configuration of opening 52 which provides the desired air diffusion and distribution. The dotted lines 60, FIG. 4, represent the bend or hinge lines of the deflectors 58.
As will be appreciated from FIGS. 5 and 6, the lateral regions 48 of the diffuser blank are bent upwardly 37° from the plane of the base 40, and the baffle end portions 62 immediately adjacent the lateral edges 46 are further bent to a vertical orientation as will be appreciated from FIG. 5.
The diffuser 38 is oriented to the heat exchanger 24 in a manner as will be appreciated from FIGS. 1 and 2, wherein the length of the openings 52 is disposed parallel to the length of the heat exchanger 24. Accordingly, the air passing through the diffuser openings 52 will be distributed along the length of the heat exchanger, and the air will pass over the heat exchanger fins 32 wherein the air will absorb heat therefrom and the diffused air also passes over thermal sensor 25.
Air entering the diffuser through the openings 52, to a limited extent, will also flow through the vent holes 50 defined in the lateral regions 48, and this air will pass over the heat exchanger ends 34 and 36 keeping the ends of the heat exchanger from overheating. However, it will be understood that the majority of the air being diffused by the openings 52 passes over the heat exchanger plates 32.
An upper baffle 64 is located within the plenum 20 above the heat exchanger 24, and includes upwardly converging walls extending towards the hose fitting 22 and plenum outlet 30. The upper ends of the baffle 64 terminates short of the upper surface of the plenum 20 whereby air flowing through the vent holes 50 will enter the hose fitting 22, and the mixture of the forced air being blown through the openings 52, and vent holes 50, produces a well diffused flow of air over the thermal sensor 25 and into the hose fitting 22 of even temperature throughout the area of the hose fitting and thermal sensor assuring an evenly heated distribution of air within the hose 12 as discharged into the blanket 10 and assuring accurate air temperature sensing.
The configuration of the openings 52, and the use of the deflectors 58, produces a flow of air over the heat exchanger 24 creating considerable turbulence as to produce the desired mixture of air to reduce hot or cold "spots" upon the heat exchanger 24, its fins 32 and the air column above the heat exchanger 24. The diffuser 38 is of a concise configuration readily receivable within the plenum 20, and as the diffuser is formed of sheet metal by a stamping operation a high strength is achieved at minimum fabrication costs.
It is appreciated that various modifications to the inventive concepts may be apparent to those skilled in the art without departing from the spirit and scope of the invention.
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An air diffuser system for a medical thermal blanket wherein air forced over an elongated heat exchanger is substantially uniformly distributed over the heat exchanger and a thermal sensor located downstream over the heat exchanger to eliminate localized hot and cold "spots" and permit accurate temperature measurement of the air and provide an effective exchange of heat between flowing air and the heat exchanger, the apparatus of invention is characterized by its concise configuration and dimensions.
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BACKGROUND OF THE INVENTION
[0001] I. Field of the Invention
[0002] The present invention relates to an Internet marketing method and game, and, more particularly, to such a marketing method in which a game is designed to attract visitors to a web site and to retain their attention while a variety of ads are displayed.
[0003] II. Description of the Related Art
[0004] Marketing of products and services via the Internet has exploded in recent years. Just as in standard marketing, it is a constant challenge to get potential customers to visit or “hit” on a marketer's web site. There are literally millions of Internet/World Wide Web sites which are accessible by users of the Internet. A problem with using such Web Sites as a marketing tool is the huge number of options available to a user. In other words, without some incentive or direction for a user to access a particular company's web site, there is little likelihood that a particular user will access that web site, or even be aware of its existence.
[0005] Many different creative methods of encouraging customers to access marketing web sites have been developed primary among which is the use of “banner ads” or other advertising space and images which are displayed on search engines, etc. A problem with such banner ads is the limited time exposure to a potential customer presented by a search engine or other general interest web site.
[0006] It is apparent that a new marketing strategy and method is needed to take advantage of the Internet to provide a more reliable exposure of potential customers to a marketer's advertisements. Such a marketing strategy should encourage a maximum number of individuals to come to the web site featuring the advertisements, and to remain there for a time sufficient to view all of the available advertisements, and/or to repeatedly view particular ones of the advertisements.
SUMMARY OF THE INVENTION
[0007] The present invention is an Internet marketing game designed for promoting access to the web site which hosts the game, and to keep potential consumers occupied on the web site for exposure to several different advertising spaces, or to a few such advertising spaces repeatedly. The advertising spaces can be the property of the promoter of the game web site, or, alternatively, some or all of the space can be sold to other web site marketers.
[0008] The inventive game is centered around a “point and click” system in which a screen display is provided which includes an image made up of a large number of individual pixels. A player is encouraged to move a cursor, by mouse or the like, around the image and to randomly select a pixel or image area on the image by clicking on the mouse button. The x-y coordinate location of the pixel or image area is then compared against stored x-y coordinates for winning pixel or image area location(s). If the location of the selected pixel or image area matches the pixel or image area location randomly selected and stored, then the player wins a prize. Players are encouraged to play the game as many times as they like, and with each play, one or more advertisements are displayed on the screen outside of the picture. Of course, with a large number of pixels on a typical image, selection of a particular winning pixel or image area location at random is an extremely small probability. In the example given herein as a preferred embodiment, the game is called THE TREELOOT GAME SM and the image is of a “money tree”, i.e. a tree supporting thousands of dollar bills.
OBJECTS AND ADVANTAGES OF THE INVENTION
[0009] The principle objects and advantages of the invention include: to provide an Internet marketing method and game; to provide such a marketing method and game which encourages potential customers to visit the web sites of game sponsors; to provide such a marketing method and game in order to build an Internet audience; to provide such a marketing method and game in which a game image is displayed to a player along with advertisements for game sponsors; to provide such a marketing method and game in which a player is prompted to select an image area on the game image by “pointing and clicking” thereon; to provide such a marketing method and game in which one or more winning image areas are stored in memory to be compared against the image areas selected by a player to determine if a winning “match” has been made; to provide such a marketing method and game in which a player is encouraged to repeatedly play the game, thus repeatedly exposing the player to advertisements of game sponsors; to provide such a marketing method and game in which each losing game round results in a losing response page being displayed to the player, which response page also includes at least one game sponsor ad; to provide such a marketing method and game which effectively exposes multiple potential customers to a sponsor's ad for extended periods; to provide such a marketing method and game which generates advertising revenue; to provide such a marketing method and game which can act as a cross-promotion for other web sites and/or games; and to provide such a marketing method and game which is particularly effective for its intended purpose.
[0010] Other objects 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.
[0011] 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
[0012] [0012]FIGS. 1 a and 1 b , collectively, are a schematic block diagram representing the Internet Marketing Game according to the present invention.
[0013] [0013]FIG. 2 is a representative screen display illustrating the web site for the inventive Internet Marketing Game.
[0014] [0014]FIG. 3 is a representative screen display illustrating an example of a “Money Tree” image from which a pixel or image area is selected by a player in playing the inventive Internet Marketing Game.
[0015] [0015]FIGS. 4 and 5 are alternative randomly selected losing response pages.
[0016] [0016]FIGS. 6 and 7 are two different dynamically generated losing response pages which are customized to the particular player and game situation.
DETAILED DESCRIPTION OF THE INVENTION
[0017] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in any desired manner.
[0018] Referring to FIGS. 1 a and 1 b , a block schematic diagram represents the logic of the inventive Internet Marketing Game. At block 1 , the game server is started and block 2 represents the loading of error files. This is an HTML file read into memory which the server is programmed to output in the event of a fatal error. Block 3 represents the loading of bonus information for that particular period, such as, e.g. a 24 hour period. This information includes parameters for bonus and “secret bonus” rounds, with each such parameters being read from the file and parsed into its particular internal representation. Block 4 represents the loading of image information for the particular image being used for the game. The rules of the game dictate that only pixel or image areas selected within the image boundaries can be winning locations, e.g. the tree foliage, the trunk or surrounding grass in the case of a “money tree”. This step involves the loading of image “mask” files which define the image areas for a later generation of bonus round prize locations on the image.
[0019] At block 5 , the server connects to a database just this once, upon start-up. In the event that an error is detected in the loading of any of this information, or the connection to the database, the program is automatically exited, as indicated by blocks 11 - 14 .
[0020] At block 15 , the price information for prizes being awarded during the particular period is loaded. This step includes the loading of prize status information as well as the pixel or image area coordinate locations of the prizes available for the game. This information is read in and parsed to individual memory locations. At block 21 , the statistical data is initialized for the game for that period. The game server maintains a variety of internal statistics about the game and the web site, including, without limitation, number of requests handled time spent handling requests, etc. and this step indicates the initialization of these statistics.
[0021] At block 22 , the game server waits for a request by a customer accessing the web site. The game server is a standard TCP/IP protocol server, performing in the outermost request loop in the standard TCP/IP. The server performs the standard HTTP server steps of creating a TCP server socket, waiting for requests to come into that socket, decoding those requests, and dispatching the appropriate routines to handle the request. This block indicates the waiting step of that server process. At block 23 , the server determines whether the request is administrative in nature, or is a game request. This is the decoding and dispatching steps of the server process. Decoding of the request is performed by examining the target of the FET HTTP command and for examining any HTTP “cookie” present in the request. The server divides the requests into three general categories, namely Exit requests, which can only come from an administrator; Administrative Requests, which can also only come from a system administrator; and Game Requests, which come from a player. Game Requests are generated by a player's HTTP browser in communication with the Game Server, and include the pixel or image area location of a player pointing and clicking on the image in playing the game.
[0022] If the request is administrative, as indicated at block 24 , the server determines what type of administrative function is being requested, at block 25 . Three examples are illustrated, including block 31 , reloading price values, block 32 , reloading bonus values, and block 33 , printing statistics to the user. Once the selected administrative function is performed, the server again waits for a further request.
[0023] Another administrative function is represented by block 34 , where the game server can be selectively shut down by an authorized administrator.
[0024] Conversely, if the request is a game request, as indicated at block 40 , in the form of a code including a selected (x,y) pixel or image area coordinate location on the tree, the specific game situation for which the request was generated, i.e. main round, bonus round, etc., and a verification that the request was originated by a “click” on the game image from the player's browser (as opposed, e.g., to being typed in manually). At block 41 , the selected pixel or image area location is compared against the winning pixel or image area locations for the prize list for that time period in order to determine whether the selection is a winner. If the selected pixel or image area location matches the winning location, at block 42 , a winner's form (an HTML form that the winner must fill out and submit) is output to the player and the server is returned to the request waiting status of block 22 .
[0025] If the selected pixel or image area location does not match the winning pixel or image area location, at block 43 , the server determines whether a random response page or a rules based dynamic response page will be generated. This is determined by a complex set of rules which determine how exactly to respond to the unsuccessful player. For example, the second displayed losing response page will ask for an identifier in the form of an alphanumeric character string. If the player does not enter any such identifier, then he is assigned a simple identifier such as “friend” for future dynamic response pages. Dynamic response pages which are customized to that player's identifier depending upon the player's selected pixel or image area location, time of day, the number of times a player has accessed a banner ad link, the number of consecutive “plays” by that player, etc. For example, as the player's selections get closer to a winning location, the dynamically generated response page might be something like “Friend, you are getting warmer”. Of the two broad response types, the random pages are static, prewritten “pages” (files with text and HTML markup codes) which are randomly chosen from a large number of such pages. The dynamic pages are generated by special purpose routines in the server so that they can be customized to the particular player and game situation. Each player is tracked by a unique “cookie”, i.e. a unique identifier sent from server to the player's browser when the player initially accesses the game web site. The player's cookie is then used for purposes of generating the dynamic response pages.
[0026] Based upon this decision, either, at block 44 , a random losing response page is selected from storage and displayed, with a message which attempts to get the player to play again, in addition to displaying one or more advertisements; or, at block 51 , a dynamic, personalized losing response page is generated and displayed, also with an invitation to play the game again, along with displaying one or more advertisements. In either scenario, after providing the response page, the server is then returned to the request waiting status of block 22 .
[0027] [0027]FIG. 2 illustrates a representative web site for the inventive Internet marketing game, generally indicated at 52 . The web page 52 includes a welcome banner 53 exclaiming the prizes available, as well as a plurality of alternative buttons, including “Are we legitimate?” at 54 ; “TreeLoot is 100% Free!” at 55 ; “Tell a friend!” at 56 ; “Why do we give away money?” at 57 . In addition, on the left side of the page, a series of other administrative selection areas are located, including “customer support” at 61 ; “tips” at 62 ; “how it works” at 63 ; “hall of fame” at 64 ; and “rules” at 65 . Other selectable regions of the web page 52 include “Bookmark this site now!” at 71 , which includes instructions on making the site a start page; “Chat with other players” at 72 ; a “Comments” option at 73 ; an e-mail sign-up option at 74 ; and a “winner's reactions” option at 75 . Of course, many other administrative functions can be displayed here as well, including color and display customization options, etc. Approximately centered on the web page 52 is a game selection area 76 which allows a player to access the game page, as explained below.
[0028] [0028]FIG. 3 illustrates a representative game page, generally indicated at 81 . The game page 81 includes a large image of a “money tree” 82 with a large number of images of dollar bills 83 on the tree. In addition, a banner 84 inviting the player to “play as many times as you like for free!” is provided at the top of the page, along with an instruction banner 85 . Immediately above the money tree image 82 is a banner ad 86 , which can be constant during any one game selection, or can be alternated with other advertisements. Other advertisements 87 , 88 can be located on the game page 81 as well, as illustrated. Of course, each banner ad 86 , etc. is designed to catch the eye of a player, and each has a message 91 which reminds the player that they do not need to leave the game site to access the sponsor's web page.
[0029] [0029]FIGS. 4 and 5 are alternative random response pages to a losing game attempt, with various messages 94 , 95 designed to entice the player to play again, and/or to visit the sponsoring advertisements 96 , 97 , respectively.
[0030] [0030]FIGS. 6 and 7 are examples of dynamic response pages generated specifically for that player based upon one or more of a number of factors. For example, FIG. 6 includes a message 98 informing the player of the number of times they have played the game thus far. FIG. 7 includes a message 99 generated in response to the player “clicking” on a pixel or image area which is reasonably close to a predetermined winning pixel or image area location for a $20 prize. In both FIGS. 6 and 7, as in FIGS. 4 and 5, sponsor's advertisements 100 and 101 , respectively, are displayed as well.
[0031] While the game image has been illustrated as a money tree, it should be made clear that the game image could be virtually any image occupying a large number of pixels, e.g. a giant image of a dollar bill, a diamond mine, etc. The game image could also be changed with each successive play, or with each time the player plays a predetermined number of successive plays. The terms HTML, TCP/IP and other specific languages and protocols, etc. used herein, are exemplary only, and should not be considered as limiting. Many other changes will be apparent to one of skill in the art without departing from the spirit of the invention. It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown.
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An Internet marketing method and game is designed for promoting access to the web site which hosts the game, and to keep potential consumers occupied on the web site for exposure to several different advertisements, or to a few advertisements repeatedly. The inventive game is centered around a “point and click” system in which a screen display is provided which includes a game image made up of a large number of individual pixels. A player is encouraged to randomly select a pixel or image area location on the game image which selected pixel or image area location is then compared to one or more stored prize winning pixel or image area locations. Players are encouraged to play the game as many times as they like, and with each play, one or more advertisements are displayed on the screen outside of the picture, and on losing response pages with each additional “play” of the game.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to holding devices and more particularly pertains to an gravestone flower holder for supporting flowers proximal to a gravestone.
2. Description of the Prior Art
The use of holding devices is known in the prior art. More specifically, holding devices heretofore devised and utilized are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
Known prior art holding devices include U.S. Pat. No. 5,072,542; U.S. Pat. No. 4,722,160; U.S. Pat. No. 4,631,859; U.S. Pat. No. 4,21 7,729; and U.S. Pat. No. Des. 305,876.
While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a gravestone flower holder for supporting flowers proximal to a gravestone which includes a main body having a plurality of apertures extending therethrough for receiving flower stems, and a mounting assembly coupled to the main body and extendable about a gravestone to mount the device relative thereto.
In these respects, the gravestone flower holder according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of supporting flowers proximal to a gravestone.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of holding devices now present in the prior art, the present invention provides a new gravestone flower holder construction wherein the same can be utilized for supporting flowers proximal to a gravestone. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new gravestone flower holder apparatus and method which has many of the advantages of the holding devices mentioned heretofore and many novel features that result in a gravestone flower holder which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art holding devices, either alone or in any combination thereof.
To attain this, the present invention generally comprises a holder for supporting flowers proximal to a gravestone. The inventive device includes a main body having a plurality of apertures extending therethrough for receiving flower stems. A mounting assembly is coupled to the main body and extendable about the gravestone to mount the device thereto.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially 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 gravestone flower holder apparatus and method which has many of the advantages of the holding devices mentioned heretofore and many novel features that result in a gravestone flower holder which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art holding devices, either alone or in any combination thereof.
It is another object of the present invention to provide a new gravestone flower holder which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new gravestone flower holder which is of a durable and reliable construction.
An even further object of the present invention is to provide a new gravestone flower holder 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 gravestone flower holders economically available to the buying public.
Still yet another object of the present invention is to provide a new gravestone flower holder 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.
Still another object of the present invention is to provide a new gravestone flower holder for supporting flowers proximal to a gravestone.
Yet another object of the present invention is to provide a new gravestone flower holder which includes a main body having a plurality of apertures extending therethrough for receiving flower stems, and a mounting assembly coupled to the main body and extendable about a gravestone to mount the device relative thereto.
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 isometric illustration of a gravestone flower holder according to the present invention in use.
FIG. 2 is a top plan view of the invention in use.
FIG. 3 is a front elevation view of the invention, per se.
FIG. 4 is a cross sectional view of the area set forth in FIG. 2.
FIG. 5 is a cross sectional view taken along line 5--5 of FIG. 3.
FIG. 6 is a cross sectional view taken along line 6--6 of FIG. 3.
FIG. 7 is an exploded isometric illustration of a coupling comprising a portion of the present invention.
FIG. 8 is an exploded isometric illustration of an alternative form of the present invention in use.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings, and in particular to FIGS. 1-8 thereof, a new gravestone flower holder embodying the principles and concepts of the present invention and generally designated by the reference numeral 10 will be described.
More specifically, it will be noted that the gravestone flower holder 10 comprises a main body 12 positionable in front of a gravestone 14 within a cemetery or like area. The main body 12 includes a plurality of flower apertures 16 directed therethrough permitting insertion of the stems of flowers 18 through the main body for support of the flowers relative to the gravestone 14. A mounting means 20 is coupled to the main body 12 for securing the main body relative to the gravestone 14. By this structure, the flowers 18 can be supported in an organized fashion relative to a gravestone within a cemetery as desired.
The main body 12 is preferably substantially rectangular in shape and desirably includes a open lower end 22 (see FIG. 6) permitting insertion and growth of live flowers 18 through the flower apertures 16 and into soil positioned beneath the main body 12 during use as illustrated in FIG. 1. To further secure the main body 12 relative to the gravestone 14, a plurality of spikes 24 extend from the main body 12 for piercing insertion into the ground surface positioned therebeneath. By this structure, live or artificial flowers 18 can be inserted through the flower aperture 16 for support relative to the gravestone 14 as desired.
As shown in FIG. 2, the mounting means 20 according to the present invention 10 preferably comprises a first strap 26 extending from a first side of the main body 12 and a second strap 28 extending from a second side of the main body 12. The straps 26 and 28 are operable to encompass a gravestone 14, with a coupling means 30 being provided with the invention 10 for removably coupling the distal ends of the straps 26 and 28 together about the gravestone 14. By this structure, the main body 12 can be further secured relative to the gravestone 14 in combination with the spikes 24, or alternatively, in lieu of the spikes 24.
As illustrated in FIGS. 2, 5, and 6, it can be shown that the first and second straps 26 and 28 are preferably contiguous in configuration and each include an upwardly projecting L-bracket 32 extending into a receiver 34 mounted to a rear wall 36 of the main body 12. The L-bracket 32, as shown for the second strap 28 within FIG. 5, is simply slidably positioned between the receiver 34 and the rear wall 36 so as to couple the strap 28 relative to the main body 12. By this structure, the main body 12 can be simply disconnected from the mounting means 20 through an upward lifting motion of the main body 12 along a front face of the gravestone 14.
Referring now to FIGS. 4 and 7, it can be shown that the coupling means 30 of the mounting means 20 preferably comprises a projection 38 extending from the first strap 26 which is received within one of a plurality of adjustment apertures 40 formed in a spaced relationship along the second strap 28. A securing sleeve 42 is slidably positioned over the straps 26 and 28 to secure the projection 38 within an individual one of the adjustment apertures 40. By this structure, the coupling means 30 permits easy coupling and adjustment of the first strap 26 relative to the second strap 28.
Referring now to FIG. 8, wherein an alternative form of the present invention is illustrated in detail, it can be shown that the main body 12 may alternatively comprise a mesh screen member 44 having a plurality of flower apertures 16 directed therethrough for receiving the stems of flowers 18. The mounting means 20 of the alternative form of the invention comprises an elastic strap 46 having a plurality of mounting apertures 48 through which a plurality of mounting projections 50 of the main body 12 project to secure the mesh screen member 44 relative to the elastic strap 46. The elastic strap 46 of the alternative form of the mounting means 20 is positionable around an upper portion 52 of the gravestone 14 so as to secure the mesh screen member 44 relative thereto. The elastic strap 46 may include a plurality of transverse projections 54 extending in a substantially parallel and spaced orientation relative to one another which cooperate to enhance frictional engagement between the elastic strap and the upper portion 52 of the gravestone 14 to which it is attached, as shown in FIG. 8. By this structure, flowers 18 can be engaged to the mesh screen member 44 and suspended relative to the gravestone 14 as desired.
In use, the gravestone flower holder 10 according to the present invention can be easily utilized to suspend flowers 18 relative to a gravestone 14 within a cemetery to decorate such gravestone as desired by an individual. As stated above, live or artificial flowers, such as silk flowers or the like can be interchangeably positioned within the main body 12 as desired.
As to a further discussion of the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
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A holder for supporting flowers proximal to a gravestone. The inventive device includes a main body having a plurality of apertures extending therethrough for receiving flower stems. A mounting assembly is coupled to the main body and extendable about the gravestone to mount the device thereto.
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BACKGROUND INFORMATION
A media gateway may be used for routing network traffic, e.g., calls. For example, a media gateway may be used, in conjunction with a policy server, to determine a destination for an incoming call, and to route packets associated with the incoming call to an appropriate destination. The destination may be associated with a particular customer or user. The customer may be served by a set of one or more trunks, each trunks including one or more links, e.g., Trunk Level 1 (T-1) links. Unfortunately, mechanisms are presently lacking for evaluating the health of a media gateway, e.g., for identifying and analyzing congestion events.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates an exemplary call processing system.
FIG. 2 illustrates an exemplary set of data that may be obtained from a media gateway by querying the gateway to show, in real-time or near real-time, congestion related information for a shelf in the gateway.
FIG. 3 illustrates an exemplary set of data that may be obtained from a media gateway by querying the gateway to show certain elements of the gateway's configuration.
FIG. 4 illustrates an exemplary data set that includes elements showing statistics obtained from a gateway relating to congestion over a given period of time.
FIG. 5 illustrates an exemplary process for obtaining data from a media gateway.
FIG. 6 illustrates an exemplary process for receiving and analyzing alarm data from a media gateway.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 illustrates an exemplary system 100 for processing calls that includes a call hub 105 , e.g., a central office or the like for switching and routing telecommunications. Incoming calls 110 from telecommunication network carriers, e.g., from time division multiplex (TDM) networks, are received in the call hub 105 in a digital cross connect (DCC) 115 . The call hub 105 includes at least one media gateway 120 , and generally includes multiple media gateways 120 , although only one media gateway 120 is illustrated and discussed herein for convenience. The media gateway 120 receives a TDM call 110 from DCC 115 , and provides a stream of packets for the call 110 to be routed by a router 130 according to instructions provided to the media gateway 120 by a policy server 165 . Records relating to calls 110 may be stored in a call database 125 . A signaling gateway 135 receives signaling information for call setup from the router 130 , serving as an interface between the call hub 105 and a signaling system 7 (SS7) network 145 . A signal transfer point 140 sends and receives signaling information to and from the signaling gateway 135 and the network 145 for setup of calls 110 .
As described herein, the health of one or more media gateways 120 included in the call hub 105 may be monitored. For example, metrics relating to congestion in a media gateway 120 may be monitored. In general, congestion in a media gateway 120 is defined as the condition that arises when the media gateway 120 is presented with traffic in excess of available bandwidth. Depending on its severity, a congestion condition can cause the quality of a data transmission, e.g., a call, to be degraded to varying degrees, or even terminated.
DCC 115 is well known for providing lines that carry voice and data signals. As is known, lines are connected to ports in DCC 115 , and DCC 115 allows users to digitally, rather than manually, connect lines by providing commands indicating which ingress and egress ports in DCC 115 are to be connected to one another.
Media gateway 120 generally includes what is generally referred to as a media gateway and media gateway controller. For example, in one implementation, media gateway 120 is the GSX9000 High-Density Media Gateway sold by Sonus Networks, Inc. of Westford, Mass. Media gateway 120 may receive TDM calls 110 , and provide the calls 110 to router 130 according to Internet protocol (IP). Although only one media gateway 120 is shown in FIG. 1 , the system 100 generally includes multiple media gateways 120 .
Database 125 is generally a relational database or the like for receiving and storing records related to calls 110 . The database 125 generally includes instructions stored on a computer readable medium and executable by a computer processor for storing, processing, and providing records, e.g., in response to queries.
Router 130 provides internal and external routing functionality in a packet network. For example, in one implementation, the router 130 performs operations for both Open System Interconnect (OSI) Layers 2 and 3, thus operating as both an Ethernet switch and a network router. Although only one router 130 is shown in FIG. 1 , the system 100 generally includes multiple routers 130 .
The signaling gateway 135 allows the media gateway 120 to interface with the SS7 network 145 . For example, in one implementation, signaling gateway 135 is the SGX4000 Universal Signaling Gateway sold by Sonus Networks, Inc. Signaling gateway 135 provides interfaces for signaling according to protocols associated with the SS7 network 145 , including Integrated Services Digital Network User Part (ISUP) and Transactional Capabilities Application Part (TCAP). Thus, signaling gateway 135 terminates links from SS7 network 145 , and converts ISUP messages to IP messages and accordingly provides IP links in the direction of router 130 .
Signal transfer point (STP) 140 is a conventional signal transfer point for use in an SS7 network. Thus, STP 140 includes a packet switch for transferring messages between call hub 105 , and nodes in the SS7 network 145 .
Administrative server 150 may include a memory 151 , a processor 152 and instructions stored on computer readable media of one or more computing devices, and may be used for various operations in call hub 105 . For example, the administrative server 150 may include a data collector 155 , i.e., script, software application, etc., for gathering and analyzing information from media gateway 120 , as discussed further below. Further, administrative server 150 may be configured to provide a graphical user interface (GUI) 160 , such as a webpage or the like. Administrative server 150 may also, e.g., via GUI 160 or some other interface, provide a mechanism for a user to query media gateway 120 , and receive data from media gateway 120 concerning call transfer operations.
Policy server 165 provides policy and routing services for media gateway 120 . For example, the policy server 165 includes a database of signaling addresses for routing calls 110 , and may receive signaling information from the media gateway 120 , and provide instructions to the media gateway 120 on how to establish a call 110 .
FIG. 2 illustrates an exemplary set of data 200 that may be obtained from a media gateway 120 by querying the gateway 120 to show, in real-time or near real-time, congestion related information for a shelf in the gateway 120 . Media gateway ID 205 is an identifier for a media gateway 120 from which the data set 200 was obtained. Media gateway ID 205 is utilized because call hub 105 generally includes multiple media gateways 120 .
Shelf ID 210 and slot ID 215 identify particular locations in the media gateway 120 . Shelf ID 210 identifies a particular shelf in the media gateway. Slot ID 215 identifies a slot in the identified shelf.
MC level 220 specifies a congestion level experienced by the media gateway 120 . For example, congestion levels may be indicated by integers ranging from 0 to 3, where 0 indicates no congestion, and 3 indicates a highest level of congestion.
CPU level 225 specifies a level of utilization of a central processing unit (CPU) or units in media gateway 120 , e.g., according to integers ranging from 0 to 3, where 0 indicates no CPU usage and 3 indicates a highest level of CPU usage, e.g., 100% or near 100% usage.
Memory level 230 indicates a level of usage of a memory in the media gateway 120 , e.g., according to integers ranging from 0 to 3, where 0 indicates no memory usage and 3 indicates a highest level of memory usage, e.g., 100% or near 100% usage.
Call rate level 235 indicates a level of a rate at which calls are presented to the media gateway 120 . For example, call rate level 235 may be expressed in a range of 0 to 3, where 0 indicates no calls are being presented, and 3 indicates a highest call rate level.
ICM level 240 indicates a level of inter-card messaging within the gateway 120 . Inter-card messaging refers to messaging between the circuit cards within the media gateway 120 . For example, ICM level 240 may be expressed in a range of 0 to 3, where 0 indicates no messaging, and 3 indicates a highest level of messaging.
MC duration 245 indicates, e.g., in seconds, a period of time for which the presently reported congestion level, i.e., MC level 220 , has been present in the media gateway 120 .
Call arrival rate 250 provides a rate at which calls are arriving in the gateway 120 , e.g., in terms of calls per second.
Call accept percentage 255 indicates a percentage of calls provided to the gateway 124 switching that are accepted by the gateway 120 . Call except percentage 255 may be computed by dividing call except rate 260 , discussed in the next paragraph by call arrival rate 250 , discussed in the preceding paragraph.
Call accept rate 260 indicates a rate at which calls are being accepted in the gateway 120 . For example, call accept rate 260 may be expressed in terms of a number of calls being accepted per second.
Some or all of the foregoing elements of the data set 200 may be stored in database 125 . Further, various logic may be applied to these elements to evaluate the health of the gateway 120 . For example, in one implementation, data collector 155 collects the data set 200 from media gateway 120 on a periodic basis. Data collector 155 may store the data set 200 in database 125 , and may further evaluate elements of the data set 200 . For example, if the data collector 155 determines that any of MC level 220 , CPU level 225 , memory level 230 , or ICM level 240 are not zero, or if call accept percentage 255 is not 100%, a poor health condition may be noted, and further an alert, e.g., an indication in GUI 160 , an e-mail or other message to an administrator, etc., may be provided.
FIG. 3 illustrates an exemplary set of data 300 that may be obtained from a media gateway 120 by querying the gateway 120 to show certain elements of a configuration of the gateway 120 . The record 300 includes a gateway ID 205 , and a shelf ID 210 , as discussed above with respect to FIG. 2 .
The record 300 includes adaptive MC level 305 , which indicates an MC level 220 at which the gateway 120 begins to manage for a congestion condition. Managing for a congestion condition could include dropping data packets or terminating calls altogether.
Overload gain factor 310 specifies a numeric value, generally an integer ranging from one to ten, for system overload gain. Overload gain factor 310 is used to optimize the traffic load that a media gateway 120 will accept. Higher values result in a faster decrease in accepted load, i.e. the system will be more aggressive in rejecting traffic. In an exemplary implementation a default value for overload gain factor 310 is three.
Resample interval 315 specifies a period of time, e.g., in seconds, over which the gateway 120 is re-computing metrics related to congestion and utilization, e.g., metrics discussed above with respect to data set 200 . For example, by default, the media gateway 120 used in an exemplary implementation maintains four 15-minute intervals of data, so that at any time the previous hour of data is available. Resample interval 315 is accordingly important in determining a frequency with which the media gateway 120 should be queried.
Resource average factor 320 specifies an influence that previous internal averages (rather than a current sample) have on computations of average utilization of CPU and memory in a media gateway 120 . In an exemplary implementation, possible values for resource average factor range from zero to one hundred, and a default value is 30.
Policer state 325 may have a value of either “enabled” or “disabled.” The congestion policer of a media gateway 120 is a mechanism for ensuring that the gateway 120 accepts calls at a smooth rate. Otherwise, the gateway 120 might accept all calls for a short period of time and then reject all calls for the remainder of a sampling period.
Policer bucket state 330 specifies a control call burst handling capability of a media gateway 120 in terms of a number of calls that may be included in a burst. For example, if policer bucket state 330 is set to “20,” and no calls were received in the last one second, a congestion policer in a media gateway 120 will allow a burst of 20 calls.
Policer nonpriority threshold 335 is an indicator for whether preference should be given to emergency calls, and in one exemplary implementation may have a value of zero or one, and is generally set to zero, meaning that nonpriority and emergency calls are given equal priority.
FIG. 4 illustrates an exemplary data set 400 that includes elements showing statistics obtained from a gateway 120 relating to congestion over a given period of time. The data set 400 includes a gateway ID 205 , as discussed above.
The data set 400 further includes an MC1 (congestion level 1) count 405 . The count 405 represents a number of times that MC level 220 has had a value of 1.
MC1 total time 410 indicates a total amount of time in the given period of time that MC1 level 220 has had a value of 1.
MC2 (congestion level 2) count 415 represents a number of times in the given period of time that MC level 220 has had a value of 2.
MC2 total time 420 indicates a total amount of time in the given period of time that MC level 220 has had a value of 2.
MC3 (congestion level 3) count 425 represents a number of times in the given period of time that MC level 220 has had a value of 3.
MC3 total time 420 indicates a total amount of time in the given period of time that MC level 220 has had a value of 3.
Call arrivals 435 indicates a number of calls received in the media gateway 120 in the given period of time.
Gateway calls rejected 440 indicates a number of calls that the media gateway 120 has rejected in the given period of time.
Policy server calls rejected 445 indicates a number of calls that the policy server 165 has rejected in the given period of time.
Average call rate 450 indicates an average number of calls received in a period of time, e.g., an average number of calls per second, in the gateway 120 in the given period of time.
Peak call rate 455 indicates a maximum number of calls received in a period of time within the given period of time, e.g., a maximum number of calls received in a 1 second interval in the given period of time.
Some or all of the foregoing elements of the data set 400 may be stored in database 125 . Further, various logic may be applied to these elements to evaluate the health of the gateway 120 . For example, in one implementation, data collector 155 collects the data set 400 from media gateway 120 on a periodic basis. Data collector 155 may store the data set 400 in database 125 , and may further evaluate elements of the data set 400 . For example, if the data collector 155 determines that any of MC1 count 405 , MC1 total time 410 , MC2 count 415 , MC2 total time 420 , MC3 count 425 , MC3 total time 430 , gateway calls rejected 440 , or policy server calls rejected 445 , are greater than zero, a poor health condition may be noted, and further an alert, e.g., an indication in GUI 160 , an e-mail or other message to an administrator, etc., may be provided.
A poor health condition may further be noted based on some other combination of conditions of data sets 200 and/or 400 other than discussed above. For example, data sets 200 and/or 400 could be combined, and a poor health condition could be noted based on values of one or more elements in the combined data set, or based on multiple values from one or both of the data sets 200 and 400 .
FIG. 5 illustrates an exemplary process 500 for obtaining data sets 200 , 300 , and 400 . Process 500 is generally conducted periodically to obtain the data sets 200 , 300 , and/or 400 from a media gateway 120 . The process 500 begins in a step 505 , in which data collector 155 logs in to the media gateway 120 . Note that if call hub 105 includes multiple media gateways 120 , the process 500 may be periodically conducted with respect to each of them.
After step 505 , in step 510 , the data collector 155 issues commands to the media gateway 120 . For example, the media gateway 120 may be configured to receive predetermined queries or other commands to obtain data. Accordingly, in this step 510 , the data collector 155 may issue commands to obtain some or all of data sets 200 , 300 , and/or 400 .
Next, in step 515 , data collector 155 parses the output received from the media gateway 120 in response to the command provided in step 510 . For example, such outputs may be staged in a text file or the like, and parsed by data collector 155 according to predetermined rules, e.g., looking for delimiting characters, identifying characters indicating the start of certain fields, etc.
Next, in step 520 , data collector 155 stores the data parsed in step 515 , e.g., in database 125 . Storage of the data in a nonvolatile data store such as database 125 is optional, but recommended, inasmuch as it is often useful to have the data available for later analysis, and potentially for use in trend analysis. For example, data collector 155 may determine if a media gateway 120 has been inaccessible more than a given number of times in a given period of time, whether congestion associated with a media gateway 120 has increased or been at a given level over time, etc. In general, data collector 155 may identify and report one or more trends relating to some or all of the elements in records 200 , 300 , and 400 over a period of time.
Next, in step 525 , data collector 155 analyzes the data obtained and parsed as described above. For example, analysis of data sets 200 , 300 , and/or 400 may seek to identify poor health conditions, e.g., congestion conditions, in the media gateway 120 as described above.
Next, in step 530 , data collector 155 causes results of the analysis performed in step 525 to be provided to one or more users, e.g., via GUI 160 , e-mail or message alerts, etc. Further, the manner in which information is provided to users may be determined according to the results of the analysis. For example, if a poor health condition is identified, an e-mail or text message may be provided, whereas if a health condition is noted but is not a poor health condition, simply making information available upon user request via GUI 160 may be adequate.
Following step 530 , process 500 ends.
FIG. 6 illustrates an exemplary process 600 for receiving and analyzing alarm data from a media gateway 120 . The process 600 begins in a step 605 in which data collector 155 receives an alarm from and/or concerning a media gateway 120 . For example, an alarm may indicate that a media gateway 120 cannot be accessed, is experiencing a severe congestion level, etc.
Next, in step 610 , data collector 155 interprets the alarm, e.g., parses the alarm information received, compares an alarm code to a value in a lookup table, etc., as necessary.
Next, in step 615 , the alarm data parsed in step 610 is stored, e.g., in database 125 .
Next, in step 620 , data collector 155 analyzes the alarm data stored in step 615 , e.g., to determine one or more trends associated with the data. For example, data collector 155 may determine if a media gateway 120 has been inaccessible more than a given number of times in a given period of time, whether congestion associated with a media gateway 120 has increased or been at a given level over time, etc. In general, data collector 155 may provide output, e.g., as discussed with respect to step 625 below, relating to a number of alarms reported in a given time period, e.g., in a given day, with respect to a media gateway 120 .
Next, in step 625 , data collector 155 causes results of the analysis performed in step 525 to be provided to one or more users, e.g., via GUI 160 , e-mail or message alerts, etc. Further, the manner in which information is provided to users may be determined according to the results of the analysis. For example, if a poor health condition is identified, an e-mail or text message may be provided, whereas if a health condition is noted but is not a poor health condition, simply making information available upon user request via GUI 160 may be adequate.
Following step 625 , the process 600 ends.
Computing devices such as those disclosed herein may employ any of a number of computer operating systems known to those skilled in the art, including, but by no means limited to, known versions and/or varieties of the Microsoft Windows® operating system, the Unix operating system (e.g., the Solaris® operating system distributed by Sun Microsystems of Menlo Park, Calif.), the AIX UNIX operating system distributed by International Business Machines of Armonk, N.Y., and the Linux operating system. Computing devices may include any one of a number of computing devices known to those skilled in the art, including, without limitation, a computer workstation, a desktop, notebook, laptop, or handheld computer, or some other computing device known to those skilled in the art.
Computing devices generally each include instructions executable by one or more computing devices such as those listed above. Computer-executable instructions may be compiled or interpreted from computer programs created using a variety of programming languages and/or technologies known to those skilled in the art, including, without limitation, and either alone or in combination, Java™, C, C++, Visual Basic, Java Script, Perl, etc. In general, a processor (e.g., a microprocessor) receives instructions, e.g., from a memory, a computer-readable medium, etc., and executes these instructions, thereby performing one or more processes, including one or more of the processes described herein. Such instructions and other data may be stored and transmitted using a variety of known computer-readable media.
A computer-readable medium includes any medium that participates in providing data (e.g., instructions), which may be read by a computer. Such a medium may take many forms, including, but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media include, for example, optical or magnetic disks and other persistent memory. Volatile media include dynamic random access memory (DRAM), which typically constitutes a main memory. Transmission media include coaxial cables, copper wire and fiber optics, including the wires that comprise a system bus coupled to the processor. Transmission media may include or convey acoustic waves, light waves and electromagnetic emissions, such as those generated during radio frequency (RF) and infrared (IR) data communications. Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM, an EPROM, a FLASH-EEPROM, any other memory chip or cartridge, a carrier wave as described hereinafter, or any other medium from which a computer can read.
With regard to the processes, systems, methods, heuristics, etc. described herein, it should be understood that, although the steps of such processes, etc. have been described as occurring according to a certain ordered sequence, such processes could be practiced with the described steps performed in an order other than the order described herein. It further should be understood that certain steps could be performed simultaneously, that other steps could be added, or that certain steps described herein could be omitted. In other words, the descriptions of processes herein are provided for the purpose of illustrating certain embodiments, and should in no way be construed so as to limit the claimed invention.
Accordingly, it is to be understood that the above description is intended to be illustrative and not restrictive. Many embodiments and applications other than the examples provided would be apparent to those of skill in the art upon reading the above description. The scope of the invention should be determined, not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. It is anticipated and intended that future developments will occur in the arts discussed herein, and that the disclosed systems and methods will be incorporated into such future embodiments. In sum, it should be understood that the invention is capable of modification and variation and is limited only by the following claims.
All terms used in the claims are intended to be given their broadest reasonable constructions and their ordinary meanings as understood by those skilled in the art unless an explicit indication to the contrary in made herein. In particular, use of the singular articles such as “a,” “the,” “said,” etc. should be read to recite one or more of the indicated elements unless a claim recites an explicit limitation to the contrary.
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Data is received from a media gateway relating to a congestion level in the media gateway. In a computer having a processor and a memory, at least a first datum and a second datum included in the data are evaluated. Based on the evaluation, it is determined whether the congestion level exceeds a predetermined level. The congestion level is reported, including whether the congestion level exceeds the predetermined level.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent Application 60/336,173 filed on Dec. 6, 2001.
BACKGROUND
1. Field of the Invention
This invention relates to devices for intrusion detection through doors and windows and more specifically relates to an adjustable alarm device for sliding doors and windows.
2. Background of the Invention
Many homes and businesses are victimized by intruders that gain unauthorized access through doors and windows. There are several patents that disclose a variety of devices that provide for locks and alarms for sliding doors and windows. However, many of these devices are mechanically complex and therefore expensive to manufacture. For example, U. S. Pat. No. 6,388,572 “Selectively Positional Intruder Alarm for Sliding Windows and Doors” issued to Salter on May 14, 2002 discloses a portable device for sliding doors and windows. This device requires specially shaped ends to engage the tracks of a window sash that opens vertically. It is not suited to horizontally sliding doors and windows and so has a limited application in a house or business setting thereby reducing its usefulness and marketability. Therefore, this is a continued requirement for a simple, inexpensive and portable sliding window and door alarm that can be used in all sliding window and door applications.
OBJECTS OF THE INVENTION
It is an object of the present invention to provide a new and improved sliding door and window alarm.
It is a further object of the present invention to provide a new and improved sliding door and window alarm that is easy to operate, simple to manufacture and inexpensive to purchase.
SUMMARY OF THE INVENTION
The above noted objects and other objects of the invention are accomplished by the provision of an adjustable alarm device for windows and doors having an elongate tubular telescoping body. The body comprises an elongate outer first tube having a first end and a second end and an elongate inner second tube having a first end and a second end. The elongate inner second tube is slidingly received within the elongate outer first tube. The second end of the elongate inner second tube extends from the first end of the elongate outer first tube. Also provided are means for releasably locking the elongate inner second tube positionally with respect to the elongate outer first tube. Also included in the invention is an elongate outer third tube, having a first end and a second end. The elongate outer third tube is coupled to the second end of the elongate inner second tube by coupling means. There is also provided an elongate inner fourth tube having an outer surface. The elongate inner fourth tube is slidingly disposed within the elongate outer third tube. The elongate inner fourth tube extends from the second end of the elongate outer third tube. Also provided is an alarm circuit that is disposed within the elongate inner fourth tube and an alarm actuation means disposed within the coupling between the elongate outer third tube and the elongate inner fourth tube.
The elongate outer first tube of the invention has an inner surface, an outer surface, an inner diameter, an outer diameter, a longitudinal axis, a first end and a second end. The elongate outer first tube also has two apertures in the second end positioned opposite each other. The elongate inner second tube also has an inner surface, an outer surface, an inner diameter, an outer diameter, a longitudinal axis, two apertures in the first end positioned opposite each other and two apertures in the second end positioned opposite each other.
The alarm device further comprises a first end plug fixed to the first end of the elongate outer first tube. The first end plug is apertured to permit air flow therethrough so that when the elongate inner second tube is pushed into the elongate outer first tube, the air that is compressed within the elongate outer first tube is released through the aperture in the first end plug.
A first collar is slideably mounted within the second end of the elongate outer first tube. The first collar comprises a flange member having a top surface and a bottom surface. The top surface of the flange member is adapted for engagement with the outer edge of the second end of the elongate outer first tube. The bottom surface of the flange member is adapted for engagement with the first end of the elongate third outer tube. The collar further includes a neck member having an inner surface and an outer surface. The neck member depends upwardly from the flange and is slideably mounted within the second end of the elongate outer tube. The neck member has an inner diameter and an outer diameter. The outer diameter is dimensioned so that the outer surface of the neck member is in sliding frictional contact with the inner surface of the elongate outer first tube. The inner diameter is dimensioned so that the inner surface of the neck member is in frictional sliding contact with the outer surface of the elongate inner second tube.
The invention further includes means for fixing the first collar to the second end of the elongate outer first tube. The means comprises two depressible lugs positioned within the neck member. Each of the two depressible lugs is positioned radially opposite the other. The two depressible lugs have outward projecting pins integral thereto that are adapted for insertion into the two apertures in the second end of the elongate outer first tube. So, when the first collar is inserted into the second end of the elongated outer first tube the pins engage the apertures thereby fixing the first collar to the outer tube. Adhesive material is also applied between the outer surface of the first collar and the adjacent inner surface of the elongate outer first tube.
The invention also provides for a circular end cap fixed to the first end of the elongate second inner tube. The end cap has a base portion that has a smooth flat outer surface and an inner surface. The end cap also has a skirt portion. The first end of the elongate second inner tube is slideably received into the skirt portion of the cap to abut against the end cap inner surface. The circular end cap further includes a camshaft mounted to the outer surface of the end cap base portion. This camshaft includes a journal member having a longitudinal axis parallel to the longitudinal axis of the elongate second inner tube, a first end and a second end. The longitudinal axis of the cam shaft journal member is disposed off-centre from the longitudinal axis of the elongate second inner tube. One end of the journal member is fixed to the outer surface of the end cap base portion and the opposite end of the journal member is free. The journal also has two tabs radially mounted to the free second end. Each of the two tabs is mounted opposite to the other and project away from the axis of the journal. The tabs have a lower bearing surface and an upper surface.
Fixing the circular end cap to the first end of the elongate second inner tube is accomplished by providing a pair of apertures disposed opposite to each other in the skirt of the circular end cap. There is also a pair of corresponding apertures each of which apertures of the pair of apertures is disposed opposite each other in the first end of the elongate second inner tube. When the end cap is placed over the first end of the elongate second inner tube the apertures correspond. A pin member is then used to penetrate the apertures thereby pinning the circular cap to the first end of the elongate inner second tube. An adhesive material is placed between the inner surface of the skirt of the circular end cap and the adjacent outer surface of the first end of the elongate inner second tube.
In one embodiment of the invention there is provided means for releasably locking the elongate inner second tube positionally with respect to the elongate outer first tube. These means comprise a circular cam body mounted on to the camshaft journal. The cam body comprises a flat circular base member having smooth flat lower surface and an upper surface. The smooth flat lower surface is adapted for sliding rotational engagement with the smooth flat outer surface of the circular end cap. A skirt depends upwards from the outer circumference of the base. The skirt has a diameter equal to the diameter of the circular end cap and has a smooth outer surface. The smooth outer surface is adapted for entering into a releasably locking frictional engagement with the inner surface of the elongate outer first tube. There is a contact finger positioned within the skirt. The contact finger depends upwardly from the smooth flat upper surface of the circular cam body. The contact finger has a fixed end attached to the base member of the circular cam body and a free end. The free end of the finger terminates at the end of the skirt and has a protuberance projecting laterally outwards. The protuberance is urged laterally outward into contact with inner surface of the elongated outer first tube for frictional sliding contact. The cam body also includes a socket penetrating the flat circular base member of the cam body. The socket has a circumferential profile identical to the circumferential profile of the journal member and the two tabs. On the inside of the cam body, there are two partitioning members raised vertically from the upper surface of the flat circular base member. These two partitioning members each have an upper edge and each transverse the upper surface of the flat circular base member. Each of the two partitioning members is positioned face to face across the socket and the profile of each of the two partitioning members follows the profile of the socket so that when the socket of the cam body is received by the journal and the two tabs mounted radially thereto, and rotated thereon, the smooth flat lower surface of the flat circular base member of the cam body is in rotational sliding contact with the smooth flat outer surface of the circular end cap, and the lower bearing surfaces of the two radially mounted tabs are in sliding contact with the upper edges of the two partitioning members.
The cam body has a first unlocked position with respect to the inner surface of the elongate outer first tube and a second locked position with respect to the inner surface of the elongate outer first tube. In the first unlocked position, the cam body skirt is disengaged from the inner surface of the elongate outer first tube and the laterally projected protuberance is in fictional contact with the inner surface of the elongate outer first tube thereby permitting controlled sliding movement between the elongate outer first tube and the elongate inner second tube. In the second releasably locked position, the cam body skirt is in tight frictional engagement with the inner surface of the elongate outer first tube thereby prohibiting any relative movement between the elongate outer first tube and the elongate inner second tube. The cam body is moved from an unlocked position to releasably locked position by twisting the elongate outer first tube and the elongate inner second tube in opposite directions thereby causing the cam body to rotate on the journal which in turn causes the cam body skirt to frictionally engage the inner surface of the elongated first outer tube. The cam body is moved from a releasably locked position to an unlocked position by twisting the elongate outer first tube and the elongate inner second tube in directions opposite to the directions taken to lock the cam body.
The elongate outer third tube has an inner surface, an outer surface, an inner diameter, an outer diameter, a longitudinal axis, a first end and a second end. The elongate outer third tube has an inner diameter equal to the inner diameter of the elongate outer first tube and an outer diameter equal to the outer diameter of the elongate outer first tube. The first end of the elongate outer third tube includes two apertures positioned opposite each other. The elongate outer third tube further includes a plurality of ribs spaced radially about the second end of the elongate outer third tube. These ribs extend longitudinally from the second end of the elongate outer third tube towards the first end of the elongate outer third tube. In profile, the ribs have an elevation from the inner surface of the elongate outer third tube sufficient to frictionally engage the outer surface of the elongate inner fourth tube thereby facilitating controlled movement of the elongate inner fourth tube relative to the elongate outer third tube.
Coupling means is provided to couple the elongate outer third tube to the elongate inner second tube. Coupling means comprise a second collar having a flange member. The flange member has a top surface and a bottom surface. The bottom surface is adapted for engagement with the outer edge of the first end of the elongate outer third tube. The top surface of the flange is adapted for engagement with the top surface of the first collar. The second collar includes a neck member that has an inner surface and an outer surface. The neck member depends upwards from the flange and is slideably mounted within the first end of the elongate outer third tube. The neck member has an inner diameter and an outer diameter. The outer diameter is dimensioned so that the outer surface of the neck member is in sliding frictional contact with the inner surface of the elongate outer third tube. Also include in the neck member are two pins depending radially from the neck member. Each of the two pins is disposed opposite the other. Each of the pins is adapted for insertion into the two apertures in the first end of the elongate outer third tube. So, when the third tube is inserted over the neck of the collar the two pins will engage the two apertures thereby fixing the collar to the elongate outer third tube. An adhesive material is applied between the outer surface of the neck member and the inner surface of the first end of the elongate outer third tube.
The second collar also comprises a first mount for mounting biasing means for biasing the alarm device against a window and a second mount for mounting alarm actuation means.
The elongate inner fourth tube comprises a housing having an outer diameter. The housing is adapted to contain a plurality of components comprising the alarm circuit. The housing further comprises a first end and a second end. The first end has a collar having an outer diameter greater than the outer diameter of the housing and less than the inner diameter of the elongate third outer tube. The collar has two biased lugs each having an embossment urged radially outwardly to engage in frictional contact with the inner surface of the elongate outer third tube permitting controlled axial sliding telescoping movement of the housing relative to the elongate third outer tube. The first end of the housing is partially enclosed by a ring having a bearing surface and adapted to bear against the biasing means for biasing the alarm against a door and window. The ring has a central hole permitting the alarm actuating device to engage the normally open switch of the alarm circuit. The second end of the housing is enclosed by a disc having an aperture in its centre. The second end of the housing further includes a ring depending upwards from the end of the second housing. The ring has an upper surface and the ring and the disc together form a hollow portion in the second end of the housing. In one embodiment of the invention the housing is a split into two symmetrical halves joined together.
The alarm device of my invention includes an alarm circuit mounted within the elongate inner fourth tube comprising a battery, a control circuit, a noise generator in the form of an audio-transducer and a normally open switch between the battery and the noise generator. In one embodiment of the invention the control circuit is mounted on to a printed circuit board. In another embodiment of the invention, the control circuit mounts a timer. The timer operates to restrict the amount of time that the noise generator will operate upon actuation to prevent depletion of the battery. In another embodiment of the invention the control circuit includes a transformer to transform battery voltage to a voltage suitable for the noise generator. The audio transducer is mounted on the upper surface of the ring and over the hollow thereby forming a resonating sound chamber beneath the audio transducer that has the effect of mechanically amplifying the sound. The alarm circuit further comprises a sound amplification body mounted over the audio transducer. The body comprises a cylindrical ring having a top edge and a bottom edge and a flange depending downwards from the bottom edge of the cylindrical ring. The flange is adapted to fit over and enclose the ring at the second end of the housing. The amplification body further includes a plano-concave disc disposed within the cylindrical ring. The disc has an aperture in its centre and the plane side of the disc is positioned above and in operative relation to the audio-transducer so that the audio-transducer, the amplification body and the resonating chamber act together to produce an amplified alarm sound.
An end cap is mounted over the amplification body. The end cap is fixed to the second end of the elongate inner fourth tube and has an outer diameter equal to the outer diameter of the elongate outer third tube. The end cap has a plurality of openings permitting sound to be transmitted.
In another embodiment of the invention there is provided a solar charger that is operatively connected to the alarm circuit to permit recharging of the battery. The solar charger comprises a plurality of photovoltaic cells suitably dimensioned to fit onto the body of the alarm device in such manner that they may be exposed to a light source while installed in a window or door frame. The solar charger further comprises means for regulating the power received from the photovoltaic cells to prevent overcharging of the battery.
In yet another embodiment of the invention there is provided a glass break alarm comprising a sound receiving device that is sympathetic to the sound of breaking glass of various types. The sound receiver is operatively connected to a memory means within the alarm circuit. A comparator compares the sound received with the sounds stored on the memory means to determine if the sound is the breakage of glass. If the breaking glass is identified then the alarm is actuated.
In a further embodiment of the invention there is provided means for detecting vibrations that might be caused by tampering with the alarm device once installed. If vibrations are detected then the alarm is actuated.
In still a further embodiment of the invention there is provided means for the detection of movement of warm bodies. For example, infra-red motion detectors may be installed on the alarm device capable of detecting the motion of persons in the proximity of the device.
In yet another embodiment of the invention, the alarm circuit is remotely connected to an alarm circuit monitoring system. In this embodiment, when the alarm circuit is triggered the alarm will sound and a signal will be remotely transmitted to a monitoring station. Authorized personnel at the monitoring station can then respond to the alarm. In another embodiment, the alarm on the alarm device may have a sound mode and a silent mode so that in the silent mode the actuated alarm will remotely transmit a signal to the remote monitoring station in a silent fashion.
In operation, the alarm device is adjusted so that the end cap of the device abuts the frame of a sliding window or door and the end cap of the elongated outer first tube abuts the opposite frame so that if the sliding door or window is moved in an open direction the device is in compression. The device is locked into position by twisting the elongate inner second tube within the elongate outer first tube. In this way, the cam body is moved from its first operating position to its second releasably locked engagement. The surface of the skirt of the cam body is frictionally engaged with the inner wall of the elongate outer first tube. The elongate inner fourth tube is biased against the biasing means and capable of sliding movement with respect to the elongate outer third tube. When the end cap is engaged with the door or window frame, the biasing means within the second collar biases the end cap against the door or window frame. In this configuration, there is a gap between the alarm actuation means and the normally open switch in the alarm circuit. If the door or window is moved in the direction of the alarm device, for example by an intruder attempting to open the sliding window or door, the end cap, attached to the elongate inner fourth tube, is depressed and the actuation means engages and closes the normally open alarm switch thereby activating the alarm.
Still further objects and advantages of the invention will become apparent from a consideration of the ensuring description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be more readily understood by reference to the following description, taken with the accompanying drawings, in which:
FIG. 1 is a side view of one embodiment of the invention in an extended configuration.
FIG. 2 is a side view of one embodiment of the invention in partially collapsed configuration.
FIG. 3 , is a side view of one embodiment of the invention in a fully collapsed configuration.
FIGS. 4A-B , are a side view and top view of the elongate outer first tube of one embodiment of the invention.
FIGS. 5A-C , are various views of the elongate inner second tube of one embodiment of the invention.
FIG. 6 , is an assembly diagram for one embodiment of the invention.
FIGS. 7A-B , are various views of the elongate outer first tube end cap of one embodiment of the invention.
FIGS. 8A-C , are various views of the elongate outer first tube first collar of one embodiment of the invention.
FIGS. 9A-D , are various views of the elongate outer first tube first collar of one embodiment of the invention.
FIGS. 10A-F , comprises various views of the end cap of the elongate inner second tube of one embodiment of the invention.
FIGS. 11A-F , comprise various views of the end cap of the elongate inner second tube of one embodiment of the invention.
FIGS. 12A-F , comprises various views of the cam body of one embodiment of the invention.
FIG. 13 , is a perspective end view of the cam body of one embodiment of the invention showing the cam body mounted to the end cap of the elongate inner second tube.
FIG. 13A , is a perspective end view of the skirt of the cam body disengaged from the inner wall of the elongate first outer tube.
FIG. 14 , is a perspective end view of the cam body of one embodiment of the invention showing the cam body in a releasably locked position and the skirt frictionally engaged with the inner surface of the elongate outer first tube.
FIGS. 15A-D , comprises various views of the elongate outer third tube of one embodiment of the invention.
FIGS. 16A-E , comprises various views of the second collar of one embodiment of the invention.
FIGS. 17A-B , comprises various views of the biasing means comprising a spring.
FIGS. 18A-C , comprises various views of the actuator means.
FIG. 19 , comprises a views of the actuation spring.
FIGS. 20A-E , comprises various views a first half body of the elongate inner fourth tube of one embodiment of the invention.
FIGS. 21A-E , comprises various views of a second half body of the elongate inner fourth tube of one embodiment of the invention.
FIG. 22 , is a sectional side view of the alarm circuit of one embodiment of the invention.
FIGS. 23A-D , comprises various views of the amplifier cap of one embodiment of the invention.
FIGS. 24A-C , comprises various views of the end cap of one embodiment of the present invention.
FIG. 25 is an assembly drawing of the invention showing the relationship between its various parts.
FIG. 26 is a circuit diagram for the basic invention.
FIG. 27 is a circuit diagram for the invention including a timer relay.
FIG. 28 is a circuit diagram for one embodiment of the invention for remote monitoring.
FIG. 29 is a circuit diagram for one embodiment of the invention with a heat sensor.
FIG. 30 is a circuit diagram for one embodiment of the invention with a photovoltaic battery charger.
FIG. 31 is a circuit diagram for one embodiment of the invention with a vibration sensor.
FIG. 32 is a circuit diagram for one embodiment of the invention with a sound detector.
FIG. 33 are views of the invention with a solar panel, sound detector for breaking glass and heat/motion detector installed therein.
DETAILED DESCRIPTION
Referring to FIG. 1 , there is shown a preferred embodiment of the invention. An adjustable alarm device for windows and doors is shown generally as ( 10 ). The alarm device has an elongate tubular telescoping body shown generally as ( 12 ) comprising an elongate outer first tube ( 14 ) having a first end ( 16 ) and a second end ( 18 ). In FIG. 1 , the elongate outer first tube ( 14 ) is depicted in a truncated fashion for illustration purposes only. The alarm device further comprises an elongate inner second tube ( 20 ) having a first end ( 22 ) and a second end ( 24 ). The elongate inner second tube ( 20 ) is slidingly received within the elongate outer first tube ( 14 ). The second end ( 24 ) of the elongate inner second tube ( 20 ) extends from the first end ( 18 ) of the elongate outer first tube ( 14 ).
The invention ( 10 ) also includes means for releasably locking the elongate inner second tube ( 20 ) positionally with respect to the elongate outer first tube ( 14 ). For example, as depicted in FIG. 1 , the relative position of the sliding elongate inner second tube ( 20 ) with respect to the stationary elongate outer first tube ( 14 ) can be releaseably locked by releasable locking means. This is described more fully below and in subsequent figures.
The invention ( 10 ) also comprises an elongate outer third tube ( 26 ), having a first end ( 28 ) and a second end ( 30 ). The elongate outer third tube ( 26 ) is coupled to the second end ( 24 ) of the elongate inner second tube ( 20 ) by coupling means which are more fully described below and in subsequent figures.
Referring now to FIG. 2 , there is shown the same embodiment of my invention ( 10 ) as shown in FIG. 1 . However, in FIG. 2 , the elongate inner second tube ( 20 ) has been telescoped into the elongate outer first tube ( 14 ). The elongate outer third tube ( 26 ) first end ( 28 ) abuts against the elongate outer first tube ( 14 ) second end ( 18 ). In FIG. 2 , additional detail is shown in the form of the elongate inner fourth tube ( 32 ) having an outer surface ( 34 ). As seen from FIG. 2 , the elongate inner fourth tube ( 32 ) is slidingly disposed within the elongate outer third tube ( 26 ). The elongate inner fourth tube ( 32 ) extends from the second end ( 30 ) of the elongate outer third tube ( 26 ).
Referring now to FIG. 3 , there is shown the same embodiment of my invention ( 10 ) as shown in FIGS. 1 and 2 . In FIG. 3 , my invention ( 10 ) is illustrated in a fully collapsed configuration. In this configuration, elongated inner second tube ( 20 ) is telescoped within elongated outer first tube ( 14 ). Elongated inner fourth tube ( 32 ) is telescoped within elongated outer third tube ( 26 ). Also illustrated in FIG. 3 , is end cap ( 36 ) more fully discussed below.
Referring now to FIGS. 4A-B , there is shown a side view of the elongate outer first tube ( 14 ) of my invention and a top view respectively. The outer first tube has an inner surface ( 48 ), an outer surface ( 50 ), an inner diameter ( 52 ), an outer diameter ( 54 ), a longitudinal axis ( 58 ), a first end ( 16 ) and a second end ( 18 ). The elongate outer first tube ( 14 ) further includes two apertures ( 60 ) and ( 62 ) in the second end ( 18 ). The two apertures are positioned opposite to each other.
Referring now to FIGS. 5A-C , there is shown the elongate inner second tube ( 20 ). A side view of the tube is shown in FIG. 5-A . A view of the tube second end is shown in FIG. 5-B and a view of the tube first end is shown in FIG. 5-C . The elongate inner second tube ( 20 ) further has an inner surface ( 64 ), an outer surface ( 66 ), an inner diameter ( 68 ), an outer diameter ( 70 ), a longitudinal axis ( 72 ), two apertures ( 74 ) and ( 76 ) in first end ( 22 ) positioned opposite each other and two apertures ( 78 ) and ( 80 ) in second end ( 24 ) positioned opposite each other.
Referring now to FIG. 6 , there is shown an assembly view of my invention ( 10 ). The first end ( 16 ) of the elongate outer first tube ( 14 ) is capped with a first end plug ( 82 ). The first end plug is apertured ( 81 ) to permit air flow therethrough. First collar ( 84 ) is slideably mounted within second end ( 18 ) of the elongate outer first tube ( 14 ). The outer edge of the second end ( 18 ) is shown as item ( 91 ).
Referring now to FIGS. 7A-B , there is shown an oblique side view of the elongate outer first tube end cap ( 82 ) and a sectional side view of the end cap respectively. The end cap comprises a base member ( 85 ), a neck member ( 89 ) and a flange member ( 87 ). The neck member ( 89 ) is adapted to frictionally fit within the first end ( 16 ) of the elongate outer first tube ( 14 ) so that the edge of end ( 16 ) abuts against the flange ( 87 ). The neck member ( 89 ) is fixed in place by adhesive material placed between the outer surface of the neck member and the adjacent inner surface of the elongate outer first tube. The end cap is apertured at ( 81 ) to permit air flow.
Referring now to FIGS. 8A-C , there is shown a sectional side view, a side view and an oblique side view respectively of first collar ( 84 ) comprising a flange member ( 86 ) having a bottom surface ( 88 ) and a top surface ( 90 ). The surface ( 90 ) of the flange ( 86 ) is adapted for engagement with the outer edge ( 91 ) of the second end ( 18 ) of the elongate outer first tube ( 14 ). The surface ( 88 ) of the flange ( 86 ) is adapted for abutting engagement with the first end ( 28 ) of the elongate third outer tube ( 26 ). The collar ( 84 ) further includes a neck ( 92 ). The neck has an inner surface ( 94 ) and an outer surface ( 96 ). The neck ( 92 ) depends upwardly from the flange ( 86 ) and is slideably mounted within the second end ( 18 ) of the elongate outer first tube ( 14 ). The neck has an inner diameter ( 98 ) and an outer diameter ( 100 ). The outer diameter ( 100 ) is dimensioned so that the outer surface ( 96 ) of the neck ( 92 ) is in sliding frictional contact with the inner surface ( 48 ) of the elongate outer first tube ( 14 ). The inner diameter ( 98 ) of the neck is dimensioned so that the inner surface of the neck ( 94 ) is in frictional sliding contact with the outer surface ( 66 ) of the elongate inner second tube ( 20 ).
Referring now to FIGS. 9A-D , there is shown a top view, a sectional side view, a side view and an oblique side view of the first collar ( 84 ). The first collar ( 84 ) further comprises means for fixing the first collar ( 84 ) to the second end ( 18 ) of the elongate outer first tube ( 14 ). Means for fixing comprises two depressible lugs ( 102 ) and ( 104 ) positioned within the neck ( 92 ). Each of the two depressible lugs is positioned radially opposite the other. Each of the two depressible lugs has outward integral projecting pins ( 106 ) and ( 108 ). The pins are adapted for insertion into the two apertures ( 60 ) and ( 62 ) in the second end ( 18 ) of the elongate outer first tube ( 14 ). So when the first collar ( 84 ) is inserted into the second end ( 18 ) of the elongated outer first tube ( 14 ) the pins ( 106 ) and ( 108 ) engage the apertures ( 60 ) and ( 62 ) thereby fixing the first collar to the outer tube. Adhesive material is also applied between the outer surface of the first collar and the adjacent inner surface of the elongate outer first tube.
Referring now to FIGS. 10A-F , the alarm device of my invention further comprises a circular end cap ( 110 ) fixed to the first end ( 22 ) of the elongate second inner tube ( 20 ). FIG. 10A is a top view of the end cap. FIG. 10-B is a sectional side view along line A—A. FIG. 10-C is a sectional side view along line B—B. FIG. 10-D is a bottom view of the end cap. FIG. 10-E is a sectional side view along line C—C and FIG. 10-F is an oblique side view of the end cap. The end cap ( 110 ) has a base portion ( 12 ) having a smooth flat outer surface ( 114 ) and an inner surface ( 116 ). The end cap also comprises a skirt portion ( 118 ). The first end ( 22 ) of the elongate inner second tube ( 20 ) is slideably received into the skirt portion ( 118 ) of the end cap ( 110 ) to abut against the end cap inner surface ( 116 ). The end cap ( 110 ) includes apertures ( 120 ) and ( 122 ). When the first end ( 22 ) of the elongate inner second tube ( 20 ) abuts against the end cap inner surface ( 116 ) apertures (I 120 ) and ( 122 ) are aligned with apertures ( 74 ) and ( 76 ) in the first end ( 22 ) of the elongate inner second tube ( 20 ). A pin ( 123 ) is inserted through the aligned apertures ( 122 , 74 , 120 and 76 ) to pin the end cap ( 110 ) to the first end ( 22 ) of the elongate inner second tube ( 20 ). Adhesive material is also added between the inner surface ( 130 ) of the end cap ( 110 ) and the adjacent outer surface ( 66 ) of the elongate inner second tube ( 20 ).
Referring now to FIGS. 11A-F , there is shown identical views of the same embodiment of the end cap ( 110 ) as shown in FIG. 10 . The circular end cap ( 110 ) further comprises a camshaft ( 132 ) mounted to the outer surface ( 114 ) of the end cap base portion ( 112 ). The camshaft ( 132 ) includes a journal member ( 134 ) having a longitudinal axis ( 135 ) parallel to the longitudinal axis ( 72 ) of the elongate second inner tube ( 20 ), a first end ( 138 ) and a second end ( 140 ). The longitudinal axis ( 135 ) of the journal member ( 134 ) is disposed off-centre from the longitudinal axis ( 72 ) of the elongate second inner tube ( 20 ). The second end ( 140 ) of the journal member ( 134 ) is fixed to the outer surface ( 114 ) of the end cap base portion ( 112 ). The first end ( 138 ) of the journal member ( 134 ) is free. The journal member ( 134 ) further includes two tabs ( 142 ) and ( 144 ) radially mounted to the free end ( 138 ) of the journal member. Each of the two tabs ( 142 ) and ( 144 ) are mounted opposite to the other and project away from the axis ( 135 ) of the journal member. Tab ( 144 ) has a lower bearing surface ( 146 a ) and an upper bearing surface ( 148 a ). Tab ( 142 ) has a lower bearing surface ( 146 b ) and an upper surface ( 148 b ).
Referring now to FIGS. 12A-F , the means for releasably locking the elongate inner second tube ( 20 ) positionally with respect to the elongate outer first tube ( 14 ) comprises a circular cam body ( 150 ) mounted on to the camshaft journal member ( 134 ). FIG. 12-A shows a top view of the cam body. FIG. 12-B shows a sectional side view of the cam body along line A—A. FIG. 12-C shows a right hand side view of the cam body. FIG. 12-D shows a bottom view of the cam body. FIG. 12-E shows an oblique top view of the cam body and FIG. 12-F shows an oblique bottom view of the cam body. The cam body ( 150 ) comprises a flat circular base member ( 152 ) having smooth flat lower surface ( 154 ) and an upper surface ( 156 ). The smooth flat lower surface ( 154 ) of the cam body ( 150 ) is adapted for sliding rotational engagement with the smooth flat outer surface ( 114 ) of the circular end cap ( 110 ). Skirt ( 158 ) depends upwardly from the outer circumference of the base ( 152 ). The skirt ( 158 ) has an outer diameter equal to the outer diameter of the circular end cap ( 110 ) and a smooth outer surface ( 160 ). The smooth outer surface ( 160 ) is adapted for entering into a releasably locking frictional engagement with the inner surface ( 48 ) of the elongate outer first tube ( 14 ). Contact finger ( 162 ) is positioned within the skirt ( 158 ). The contact finger depends upwards from the base ( 152 ). The contact finger ( 162 ) has a fixed end ( 164 ) attached to the base ( 152 ) of the circular cam body ( 150 ) and a free end ( 165 ). The free end terminates at the end of the skirt and has a protuberance ( 166 ) projecting laterally outwards therefrom. When the cam body is inserted into the elongate outer first tube ( 14 ) the protuberance ( 166 ) is urged laterally outward and into contact with inner surface ( 48 ) of the elongated outer first tube ( 14 ) for frictional sliding contact therewith. The cam body ( 150 ) also includes a socket ( 168 ) penetrating the flat circular base ( 152 ) of the cam body. The socket has a circumferential profile identical to the circumferential profile of the journal member ( 134 ) and the two tabs ( 142 ) and ( 144 ) radially mounted thereto.
Referring now to FIG. 13 , there is shown the cam body ( 150 ), the end cap ( 110 ) and the elongate inner second tube ( 20 ). The cam body ( 150 ) is mounted onto the journal member ( 134 ) through socket ( 168 ). The flat lower surface ( 154 ) ( FIG. 12 ) of the cam body ( 150 ) is in sliding contact with the flat smooth surface ( 114 ) ( FIG. 11 ) of the end cap ( 110 ). Details of the inner surface ( 156 ) of the cam body base member ( 152 ) are shown. Two partitioning members ( 170 ) and ( 172 ) are raised vertically from the inner surface ( 156 ) of the base member ( 152 ) of the cam body ( 150 ). The two partitioning members each have an upper edge ( 174 ) and ( 176 ) and each traverse surface ( 156 ). Each of the two partitioning members is positioned face to face across the socket ( 168 ) and the profile of each of the two partitioning members follows the profile of the socket. When the socket ( 168 ) of the cam body ( 150 ) is received by the journal ( 134 ) and the two tabs ( 142 ) and ( 144 ) mounted radially thereto are rotated, the smooth flat lower surface of the flat circular base member of the cam body is in rotational sliding contact with the smooth flat outer surface of the circular end cap. The lower bearing surfaces ( 146 a ) and ( 146 b ) ( FIG. 11 ) of the, two radially mounted tabs ( 142 ) and ( 144 ) are in sliding contact with the upper edges ( 174 ) and ( 176 ) of the two partitioning members. As illustrated in FIG. 13 , the tabs ( 142 ) and ( 144 ), the members ( 170 ) and ( 172 ), and the socket ( 168 ) act cooperatively to retain the cam body on the journal in a rotationally sliding engagement.
Referring now to FIG. 13A , the cam body ( 150 ) has a first unlocked position with respect to the inner surface ( 48 ) of the elongate outer first tube ( 14 ). In the first unlocked position, the cam body skirt ( 158 ) is disengaged from the inner surface ( 48 ) of the elongate outer first tube ( 14 ). The outer surface of the skirt of the cam body and the outer surface of the skirt ( 118 ) of the end cap ( 110 ) are generally flush with each other. The laterally projected protuberance ( 166 ) on the contact finger ( 162 ) is in frictional contact with the inner surface ( 48 ) of the elongate outer first tube ( 14 ). This permits controlled sliding movement between the elongate outer first tube ( 14 ) and the elongate inner second tube ( 20 ).
Referring now to FIG. 14 , the cam body ( 150 ) is shown in a second releasably locked position with respect to the end cap ( 110 ). The cam body ( 150 ) has been rotated on journal ( 134 ) so that the cam body skirt ( 158 ) is in tight frictional engagement with the inner surface ( 48 ) of the elongate outer first tube ( 14 ) thereby prohibiting any relative movement between the elongate outer first tube ( 14 ) and the elongate inner second tube ( 20 ). The cam body ( 150 ) is moved from a unlocked position to releasably locked position by twisting the elongate outer first tube ( 14 ) and the elongate inner second tube ( 20 ) in opposite directions thereby causing the cam body ( 150 ) to rotate on the journal member ( 134 ) which in turn causes the cam body skirt ( 158 ) to frictionally engage the inner surface ( 48 ) of the elongated first outer ( 14 ) tube. The cam body is moved from a releasably locked position to an unlocked position by twisting the elongate outer first tube and the elongate inner second tube in directions opposite to the directions taken to lock the cam body.
Referring now to FIGS. 15A-D , there is illustrated various views of the elongate outer third tube ( 26 ) having a first inner surface ( 192 ), a second inner surface ( 195 ), an outer surface ( 194 ), an inner diameter ( 196 ), an outer diameter ( 198 ), a longitudinal axis ( 200 ), a first end ( 28 ) and a second end ( 30 ). FIG. 15-A illustrates a side view of the outer third tube. FIG. 15-B illustrates a cross-sectional side view of the outer third tube. FIG. 15-C illustrates a first end view of the outer third tube. FIG. 15-D illustrates an oblique side view of the outer third tube. The elongate outer third tube has an inner diameter equal to the inner diameter of the elongate outer first tube and an outer diameter equal to the outer diameter of the elongate outer first tube. The first end ( 28 ) of the elongate outer third tube includes includes two apertures ( 206 ) and ( 208 ) positioned opposite each other. The elongate outer third tube ( 26 ) further includes a plurality of ribs ( 210 ) spaced radially about the second end ( 30 ) of the elongate outer third tube. The ribs extend longitudinally from the second end ( 30 ) towards the first end ( 28 ). The ribs have an elevation from the first inner surface ( 192 ) of the elongate outer third tube sufficient to frictionally engage the outer surface of the elongate inner fourth tube (described below) thereby facilitating controlled movement of the elongate inner fourth tube relative to the elongate outer third tube.
Referring now to FIGS. 16A-E , the coupling means connecting the second end ( 24 ) of elongate inner second tube ( 20 ) with the first end ( 28 ) of the elongate outer third tube ( 26 ) comprises a second collar ( 220 ) comprising a flange member ( 222 ) having a bottom surface ( 224 ) and a top surface ( 226 ). FIG. 16-A shows a top view of the coupling means. FIG. 16-B shows a side view of the coupling means. FIG. 16-C shows a sectional side view of the coupling means along line B—B. FIG. 16-D shows a sectional side view of the coupling means along line A—A and FIG. 16-E shows an oblique side view of the coupling means. The surface ( 226 ) is adapted for engagement with the outer edge ( 202 ) (illustrated in FIG. 15-B ) of the first end ( 28 ) of the elongate outer third tube ( 26 ). The surface ( 224 ) is adapted for abutting engagement with the top surface ( 88 ) (illustrated in FIG. 8-A ) of the first collar ( 84 ). The second collar ( 220 ) includes a neck ( 228 ) having an inner surface ( 230 ) and an outer surface ( 232 ). The neck depends upwardly from the flange and is slideably mounted within the first end ( 28 ) of the elongate outer third tube ( 26 ). The neck has an inner diameter ( 207 ) and an outer diameter ( 209 ). The outer diameter is dimensioned so that the outer surface of the neck is in sliding frictional contact with the second inner surface ( 195 ) (illustrated in FIG. 15-B ) of the elongate outer third tube ( 26 ). Two pins ( 234 ) and ( 236 ) depend radially from the neck ( 228 ) each of the two pins is disposed opposite the other. The pins are adapted for insertion into the two apertures ( 206 ) and ( 208 ) in the first end ( 28 ) of the elongate outer third tube ( 26 ) so when the third tube is inserted over the neck of the collar the two pins will engage the two apertures ( 206 ) and ( 208 ) thereby fixing the collar to the outer tube. Adhesive material is applied between the outer surface of the neck and the adjacent inner surface of the first end of the elongate outer third tube. The second collar ( 220 ) further comprises a first mount ( 239 ) for a first biasing means ( 400 ) for biasing the alarm device against a window and a second mount ( 241 ) for alarm actuation means ( 500 ) more fully described below.
Referring now to FIGS. 17A-B , first biasing means ( 400 ) comprises a spring having a first end ( 402 ), a second end ( 404 ) and a circumference ( 406 ). FIG. 17A shows a side view of the spring and FIG. 17B shows a top view of the spring. The first end ( 402 ) of the spring ( 400 ) is mounted into the first mount ( 239 ) of the second collar ( 220 ) as further illustrated in FIG. 25 .
Referring now to FIGS. 18A-C , alarm actuation means ( 500 ) is shown in various views. FIG. 18-A shows a bottom view of the alarm actuation means. FIG. 18-B shows a sectional side view of the alarm actuation means along line A—A and FIG. 18-C shows an oblique side view of the alarm actuation means. The alarm actuation means comprises actuation cap ( 501 ) having an outer surface ( 502 ). Actuation cap ( 501 ) is adapted to contact the normally open alarm circuit switch as more filly explained below. The actuation cap ( 501 ) further includes an inner surface ( 512 ) and two tabs ( 508 ) and ( 510 ).
Referring now to FIG. 19 , there is shown second biasing means ( 600 ) comprising a spring adapted to sit inside the actuation cap body ( 501 ) at ( 510 ). Guide slots ( 506 ) and ( 507 ) on the collar ( 220 ) receive tabs ( 508 ) and ( 510 ) on the actuation cap body ( 500 ). The first end ( 602 ) of the spring ( 600 ) abuts surface ( 608 ) (illustrated in FIG. 16-D ) and the second end ( 604 ) abuts surface ( 512 ) thereby biasing the actuation cap body ( 501 ) towards the alarm switch.
Referring now to FIGS. 20A-E and FIGS. 21A-E the elongate inner fourth tube ( 32 ) (illustrated in FIG. 2 ) comprises a first half body ( 262 a ) shown in FIGS. 20A-E and a second half body ( 262 b ) shown in FIGS. 21A-E . FIG. 20-A shows a top view of first half body ( 262 a ). FIG. 20-B shows a bottom view of first half body ( 262 a ). FIG. 20-C shows an oblique top view of first half body ( 262 a ). FIG. 20-D shows a first end view of first half body ( 262 a ) and FIG. 20-E shows a second end view of first half body ( 262 a ). FIG. 21-A shows a bottom view of second half body ( 262 b ) along line A—A. FIG. 21-B shows a side sectional view of second half body ( 262 b ). FIG. 21-C shows a top view of second half body ( 262 b ). FIG. 21-D shows an oblique view of second half body ( 262 b ) and FIG. 21-E shows a first end view of second half body ( 262 b ). FIGS. 20A-C clearly illustrates battery housing ( 315 ). To form the elongate inner fourth tube ( 32 ) the pins ( 317 ) on half body ( 262 a ) as shown in FIGS. 21B-C are pressed into pin holes ( 319 ) shown in FIG. 21 A. Each half body has an outer diameter ( 264 ). Inner fourth tube ( 32 ) is adapted to house the alarm circuit ( 324 ) and the battery ( 320 ) as illustrated in FIG. 22 . First half body ( 262 a ) comprises a first end ( 266 a ) and a second end ( 268 a ). Second half body ( 262 b ) comprises a first end ( 266 b ) and a second end ( 268 b ). First half body ( 262 a ) first end ( 266 a ) has a first half collar ( 270 a ) integral thereto. Second half body ( 262 b ) also has a second half collar ( 270 b ). The first and second collar halves ( 270 a ) and ( 270 b ) have an outer diameter ( 265 ) that is greater than the outer diameter ( 264 ) of the halve bodies ( 262 a ) and ( 262 b ) and less than the inner diameter of the elongate third outer tube. First half collar ( 270 a ) has biased lugs ( 272 ) and second half collar ( 270 b ) has biased lug ( 274 ). Each of the lugs has an embossment ( 276 ) and ( 277 ). The embossment is urged radially outwardly to engage in frictional contact with the inner surface of the elongate outer third tube, thereby permitting controlled axial telescoping movement of the inner fourth tube relative to the elongate third outer tube.
Referring still to FIGS. 20A-E and FIGS. 21A-E the first end ( 266 a ) of the first half body ( 262 a ) is partially enclosed by a first half ring ( 280 a ). Similarly, second half body ( 262 b ) is partially enclosed by a second half ring ( 280 b ). Each half ring has a bearing surface ( 282 a ) and ( 282 b ) respectively so that when the two half bodies ( 262 a ) and ( 262 b ) are joined each half ring joins to form a circular bearing surface adapted to bear against the first biasing means for biasing the alarm against a door or window. As well, each half ring ( 282 a ) and ( 282 b ) form to create a central hole ( 284 ) permitting the alarm actuating body ( 500 ) to engage the normally open switch of the alarm circuit as more fully explained below. The second end ( 268 a ) of the first half body ( 262 a ) and the second end of the second half body ( 262 b ) are is enclosed by a first half disc ( 290 a ) and a second half disc ( 290 b ) respectively. When the two half bodies are joined together to form inner fourth tube ( 32 ) the two half discs join to close that end of the tube save for an aperture in its centre ( 292 ). The second ends ( 268 a ) and ( 268 b ) further includes a third half ring ( 294 a ) and a fourth half ring ( 294 b ) depending therefrom. When the first half body and the second half body are joined, the third and fourth half rings join and together with the two half discs form a hollow ( 300 ).
Referring now to FIG. 22 , the alarm circuit is illustrated. The alarm circuit is mounted within the elongate inner fourth tube ( 32 ) and includes a battery ( 320 ), a normally open switch ( 322 ) between the battery and a board mounted control circuit ( 324 ). The control circuit includes a transformer and a timer. The alarm circuit further comprises a sound producing audio transducer ( 326 ) operationally connected to the control circuit. The audio transducer ( 326 ) is mounted on the upper surface ( 296 ) (illustrated in FIG. 21-D ) of the ring ( 294 ) and over the hollow ( 300 ) thereby forming a chamber ( 330 ) beneath the audio transducer.
Referring now to FIGS. 23A-D , the invention further comprises a sound amplification body ( 332 ) mounted over the audio transducer. FIG. 23-A shows a top view of the sound am plication body. FIG. 23-B shows a sectional side view of the sound amplification body along line A—A. FIG. 23-C shows a side view of the sound amplification body and FIG. 23-D shows an oblique bottom view of the sound amplification body. The sound amplification body comprising a cylindrical ring ( 334 ) having a top edge ( 336 ) and a bottom edge ( 338 ). A flange ( 340 ) depends downwards from the bottom edge ( 338 ) and is adapted to fit over and enclose the circular ring created by joined half rings ( 294 a ) and ( 294 b ) at the second end of inner fourth tube ( 32 ). The amplification body further includes a plano-concave disc ( 342 ) disposed within the cylindrical ring. The disc has an aperture ( 344 ) in its centre. The plane side ( 346 ) of the disc is positioned above and in operative relation to the audio-transducer ( 326 ) so that operation of the audio-transducer causes sympathetic vibration of the plano-concave disc thereby amplifying the sound emanating from the audio-transducer.
Referring now to FIGS. 24A-C , there is shown end cap ( 36 ) mounted over the amplification body ( 332 ). FIG. 24-A shows an oblique side view of the end cap. FIG. 24-B shows a sectional side view of the end cap along line A—A and FIG. 24-C shows a top view of the end cap. The end cap is fixed to the second end ( 268 ) of the elongate inner fourth tube ( 32 ) The end cap has an outer diameter equal to the outer diameter of the elongate outer third tube. The end cap has a plurality of openings ( 352 ) permitting sound to be transmitted.
Referring now to FIG. 25 , there is shown an assembly drawing illustrating the various components of my invention and the manner in which they are related and connected. All components of the invention, except the metal springs, are manufactured from molded thermoplastic material for easy manufacturing and assembly.
Referring to FIG. 26 , there is shown a simple circuit diagram of the control circuit ( 324 ) of one embodiment of the invention. The control circuit comprises a battery ( 320 ), normally open switch ( 322 ) and transformer ( 321 ) in order to power the audio transducer ( 326 ).
Referring to FIG. 27 , the preferred embodiment of the invention includes a timer ( 325 ) to limit the amount of time the audio transducer sounds so as to prevent depletion of the battery ( 320 ).
Referring to FIG. 28 , there is shown another embodiment of my invention including means for remote monitoring the invention ( 329 ). Said means is adapted to actuate when the audio transducer is actuated for remote monitoring and would notify local authorities of an alarm situation. A person skilled in the art would understand such means to include, for example, radio transmission or connection to cable or telephone services.
Referring to FIG. 29 , there is shown another embodiment of my invention including a heat detector/motion sensor ( 331 ) actuated switch ( 333 ) for detecting body heat of any potential intruder in close proximity to the alarm.
Referring to FIG. 30 there is shown yet another embodiment of my invention that uses photovoltaic cells ( 343 ) to keep the battery charged.
Referring to FIG. 31 there is shown still another embodiment of my invention that includes anti-tampering means in the form of a vibration detector ( 345 ) to actuate a switch ( 347 ) in the event that the invention is tampered with.
Referring to FIG. 32 there is shown another embodiment of my invention that includes a sound detector ( 349 ) to detect the sound of breaking glass and actuate switch ( 351 ).
Referring to FIGS. 33A-C , there are shown three embodiment of my invention relating to FIGS. 30 , 32 and 29 respectively. FIG. 33A shows the location of solar cells ( 343 ) within elongate outer third tube ( 26 ). FIG. 33B shows the location of a sound detector ( 349 ) to detect the sound of breaking glass located within elongate outer third tube ( 26 ). FIG. 33C shows the location of a heat sensor/motion sensor ( 323 ) located within elongate outer third tube ( 26 ).
Thus, having described the preferred embodiment of the invention and the best mode presently known for implementing the invention it is to be understood that certain changes could be made to the device disclosed herein without departing from what is considered to be the scope of this invention. Therefore, this specification is not to be taken in the limiting sense, but instead is to be taken and read for the purpose of interpreting the claimed invention as set forth in the following claims. Such claims and only such claims when interpreted in accordance with well established doctrine define the legal monopoly claimed herein.
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An adjustable alarm device for windows and doors is installed between the door or window frame and the door or window sash. The longitudinal axis of the alarm device is preferably horizontal. When engaged, movement of the door or window in an open direction will activate the alarm. The body of the alarm device is elongate, tubular and telescoping. The body comprises an outer tube that receives an inner tube. The body of the alarm device may be locked in an extended position by way of a cam mounted on the inner tube and positioned within the body so that when the inner and outer tubes of the body are twisted about their longitudinal axis, the cam body will engage the inner surface of the outer tube in a releasable frictional locking engagement. The alarm device is coupled to one end of the inner tube.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to paper-making machines and, more particularly, to paper-making machines having air assisted threading doctor elements.
2. Description of the Related Art
Machines for making sheets of material, especially paper, utilize an array of rotating longitudinal cylinders or rolls on which the paper travels. The rolls are used in a variety of different sections during the paper making process. One of the sections is a dryer section, which may consist of several dryer sections, situated one after another. In a dryer section, as the name implies, incoming wet paper is dried by drying rolls.
In most of the various segments of the paper machine, it is known to provide a doctor element, such as a doctor blade, which bears against a roll of the section and cleans the roll by scraping off residual fibers or the like. A water shower is typically provided in association with the doctor blade for lubricating the doctor blade as it bears against the roll. The shower directs a stream of water against the roll across the width of the doctor blade and on the approach side of the doctor blade.
In sections such as a dryer section, it is known to provide a threading doctor at the beginning of a roll in order to direct the paper onto the roll. As the paper advances along the particular section, the threading doctor associated with each roll directs the paper onto the next roll. Generally, such threading doctors have air blowing systems that direct flowing air from nozzles into the region where the paper is to separate from the roll and advance to the next roll. The blowing air forces the paper to travel away from the roll and into a convergence area of the next roll for pickup by that next roll. The use of blowing air is an efficient way to direct the advancing paper since the paper generally advances at 4,000 to 6,000 feet per minute (fpm).
However, the problem with such threading systems is the enormous air pressure required to continuously supply each blowing system associated with each roll. As an example, a typical dryer group of a dryer section includes ten (10) dryer rolls each with a blowing system having an approximate twenty (20) CFM (Cubic Feet per Minute) air flow, yielding approximately two-hundred (200) SCFM. With as many as three (3) to twelve (12) dryer groups per dryer section, this may require an air supply system of six hundred (600) to two-thousand four-hundred (2,400) SCFM.
What is thus needed is an air threading system that utilizes an air supply system of considerably less SCFM.
SUMMARY OF THE INVENTION
In one form, the present invention is a paper-making machine having an air control system. The paper-making machine has a plurality of cylinders with each cylinder having an associated air blowing threading doctor assembly. The control system for the plurality of air blowing threading doctor assemblies includes an air supply system, a controller, a plurality of air valves, and a plurality of proximity sensors. The air valves are associated with each air blowing threading doctor assembly and are in communication with the controller and the air supply system. Each air valve selectively supplies air from the air supply system to the associated air blowing threading doctor assembly upon activation by the controller. Each proximity sensor is associated with each air blowing threading doctor assembly and is in communication with the controller. Each proximity sensor generates a signal upon the detection of a leading tail of the paper within a detection zone associated with each proximity sensor. The controller activates an air valve associated with an air blowing threading doctor assembly associated with a proximity sensor that generated the signal, and additionally activates a next air valve associated with a next air blowing threading doctor assembly associated with a next cylinder relative to a paper advance direction.
Additionally, in accordance with an aspect of the present invention, the air valves to previously activated threading doctors are sequentially turned off as the leading tail of the paper advances.
In another form, the present invention is a method of controlling air blowing threading doctors in a fiber material making machine having a dryer section with a plurality of dryer cylinders, an air supply system. Each of the plurality of dryer cylinders is associated with an air blowing threading doctor that is in communication with the air supply system.
The method includes supplying air from the air supply system to the air blowing threading doctor associated with a first dryer cylinder of the plurality of dryer cylinders. The presence of a leading tail of a web of fiber material being made in the fiber-making machine is detected in a detection zone, wherein a detection zone is defined as between a dryer cylinder emergence area and a next dryer cylinder convergence area relative to a fiber web material advance direction. Air from the air supply system is supplied to the air blowing threading doctors associated with at least the next two dryer cylinders relative to the fiber web material advance direction and the detection zone when the leading tail is detected. The air is shut off to the air blowing threading doctors associated with the dryer cylinders at least twice preceding the detection zone when the leading tail is detected. The detecting, air supplying, and shutting off steps are then repeated until the leading tail is detected in a final dryer cylinder detection zone.
It is an advantage of the present invention that a smaller CFM capacity air supply system can be utilized for the air threading system.
The present invention has particular advantageous use in dryer sections of a paper-making machine.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiment of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a diagrammatic side view of an embodiment of a dryer section used with a paper making process incorporating the present invention;
FIG. 2 is an enlarged side view of a portion of the dryer section of FIG. 1 in accordance with the present invention depicting a detecting area between dryer rolls having a paper tail therein; and
FIG. 3 is a diagrammatic view of the air supply system as coupled to the blowpipes of the threading doctors and the associated proximity sensors in communication with a controller.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrate a preferred embodiment of the invention, in one form, and such exemplification is not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings and more particularly to FIG. 1, there is shown a side view of dryer group 10 forming part of a dryer section in a paper-making machine. Dryer group 10 may be one of a plurality of dryer groups which can typically number between three (3) and twelve (12) in a paper-making machine. It should be understood that dryer group 10 is representative of the plurality of such dryer groups that take the moisture out of the paper or other fiber material during the production process.
Dryer group 10 is divided into upper dryer group 12 and lower dryer group 14 , which together, move paper or fiber material web 28 therethrough, here, arbitrarily from left to right as indicated by arrow 38 . Upper dryer group 12 includes a plurality of upper dryer cylinders 16 a, 16 b, 16 c, 16 d, and 16 e, each being of generally the same size and type as is typical in the art. Each upper dryer cylinder 16 a, 16 b, 16 c, 16 d, and 16 e rotates in the direction of their respective arrow. Upper dryer group 12 also includes a plurality of upper felt guide rolls 18 a, 18 b, 18 c, 18 d, 18 e, 18 f, 18 g, and 18 h that rotatably support continuous felt sheet 20 and rotate in the direction of their respective arrow. Felt 20 travels in a continuous loop in the direction indicated by arrow 34 and is supported by upper felt guide rolls 18 b, 18 c, 18 d, 18 e, 18 f, and 18 g such that felt 20 contacts only the upper portion of each upper dryer cylinder 16 a, 16 b, 16 c, 16 d, and 16 e.
Lower dryer group 14 includes a plurality of lower dryer cylinders 22 a, 22 b, 22 c, 22 d, and 22 e, each being of generally the same size and type as is typical in the art. Each lower dryer cylinder 22 a, 22 b, 22 c, 22 d, and 22 e rotates in the direction of their respective arrow. Lower dryer group 14 also includes a plurality of lower felt guide rolls 24 a, 24 b, 24 c, 24 d, 24 e, 24 f, 24 g, and 24 h that rotatably support continuous felt sheet 26 and rotate in the direction of their respective arrow. Felt 26 travels in a continuous loop in the direction indicated by arrow 36 and is supported by lower felt guide rolls 24 b, 24 c, 24 d, 24 e, 24 f, and 24 g such that felt 26 contacts only the lower portion of each lower dryer cylinder 22 a, 22 b, 22 c, 22 d, and 22 e.
Fiber material web 28 enters dryer group 10 between lower felt guide roll 24 b and lower dryer cylinder 22 a between felt 26 and lower dryer cylinder 22 a and is then intertwined in alternating lower and upper dryer cylinders, 16 a, 22 b, 16 b, 22 c, 16 c, 22 d, 16 d, 22 e, and 16 e. In this manner, fiber material web 28 is compressed onto the surfaces of the alternating dryer cylinders by respective felts 20 or 26 . In the case of the lower dryer cylinders 22 a, 22 b, 22 c, 22 d, and 22 e, fiber web material 28 is compressed between felt 26 and the lower portion surface of the respective lower dryer cylinders. In the case of the upper dryer cylinders 16 a, 16 b, 16 c, 16 d, and 16 e, fiber web material 28 is compressed between felt 20 and the upper portion surface of the respective upper dryer cylinders. Additionally, fiber web material 28 has a beginning and end, known in the industry as a leading tail and a trailing tail respectively. The leading tail of fiber web material 28 is designated 40 , while the trailing tail of fiber web material 28 is designated 42 .
Generally, the leading tail of a fiber roll is wedge-shaped as is the trailing tail. This is due to the manner in which the paper is cut. As the paper is advancing, a blade or other type of cutter is caused to move transverse to the advancing direction. The blade thus cuts a wedge shape, with the point thereof at one side where the blade starts.
Associated with each upper dryer cylinder 16 a, 16 b, 16 c, 16 d, and 16 e is a threading doctor assembly 30 a, 30 b, 30 c, 30 d, and 30 e, respectively, each of which is positioned on the exit side, relative to paper travel, of the respective dryer cylinder.
Associated with each lower dryer cylinder 22 a, 22 b, 22 c, 22 d, and 22 e is a threading doctor assembly 32 a, 32 b, 32 c, 32 d, and 32 e, respectively, each of which is positioned on the exit side, relative to fiber web travel, of the respective dryer cylinder.
With reference now to FIG. 2, there is shown an enlarged view of an area between upper dryer cylinders 16 a and 16 b, and lower dryer cylinder 22 b particularly depicting threading doctor assembly 30 a, associated with upper dryer cylinder 16 a, and threading doctor assembly 32 b, associated with lower dryer cylinder 22 b.
Threading doctor assembly 30 a includes doctor 44 mounted as is typical in the art adjacent the outer surface of upper dryer cylinder 16 a on the exit side thereof, relative to fiber web material 28 travel through dryer group 10 . Doctor 44 may be mounted so as to be movable toward and away from the cylinder. Doctor 44 extends a portion of the longitudinal length of upper dryer cylinder 16 a. Mounted to doctor 44 is blowpipe 46 , also extending a portion of the longitudinal length of upper dryer cylinder 16 a, having a plurality of air nozzles 86 (see FIG. 3) therein. Blowpipe 46 , and thus associated air nozzles 86 , is coupled to a source of compressed or pressurized air 80 (see FIG. 3) via air conduit 48 . Air is directed, forced, or blown into emergence area 70 by air nozzles 86 of blowpipe 46 where upper felt 20 disjoins from upper dryer cylinder 16 a and fiber web material 28 , compressed between upper felt 20 and the outer surface of upper dryer cylinder 16 a, emerges. This separates the fiber web material that is compressed against upper dryer cylinder 16 a therefrom such that the fiber web material can be directed into convergence area 72 to begin travel against lower dryer cylinder 22 b with the aid of lower felt 26 .
Mounted to blowpipe 46 is proximity sensor 50 . Proximity sensor 50 may be any type of sensor, transducer, motion detector or the like that can sense or indicate whether fiber web material 28 is within sensing or detection area 54 . In one form, proximity sensor 50 is an ultrasonic generator/transducer such as a SUPERPROX® proximity sensor manufactured by Hyde Park Electronics, Inc. of Dayton, Ohio. Proximity sensor 50 is adjusted such that only material within sensing or detection area 54 generates a material sensed or detected signal. With additional reference to FIG. 3, proximity sensor 50 is in communication with controller 82 via line 52 . Controller 82 is in communication with air supply system 80 via line 78 . Air supply system 80 is coupled via conduit 78 to air valve or solenoid 76 that is coupled to conduit 48 associated with nozzles 86 of blowpipe 46 via line 78 . Controller 82 is in communication with solenoid 76 via line 90 for activation and deactivation, or on/off, control thereof. When solenoid 76 is actuated by controller 82 via line 90 in accordance with the present invention, compressed or pressurized air is caused to flow from air supply system 80 through conduit 78 and into nozzles 86 of blowpipe 46 . Of course, when solenoid 76 is deactivated or turned off, the air flow into blowpipe 46 is ceased.
Threading doctor assembly 32 b includes doctor 56 mounted as is typical in the art adjacent the outer surface of lower dryer cylinder 22 b on the exit side thereof, relative to fiber web material 28 travel through dryer group 10 . Doctor 56 may be mounted so as to be movable toward and away from the cylinder. Doctor 56 extends a portion of the longitudinal length of lower dryer cylinder 22 b. Mounted to doctor 56 is blowpipe 58 , also extending a portion of the longitudinal length of lower dryer cylinder 22 b, having a plurality of air nozzles 92 (see FIG. 3) therein. Blowpipe 58 , and thus associated air nozzles 92 , is coupled to a source of compressed or pressurized air 80 (see FIG. 3) via conduit 60 . Air is directed into emergence area 74 by air nozzles 92 of blowpipe 58 where lower felt 26 disjoins from lower dryer cylinder 22 b and fiber web material 28 , compressed between lower felt 26 and the outer surface of lower dryer cylinder 22 b, emerges. This separates the fiber web material that is compressed against lower dryer cylinder 22 b therefrom such that fiber web material 28 can be directed into convergence area 88 to begin travel against upper dryer cylinder 16 b with the aid of upper felt 20 .
Mounted to blowpipe 58 is proximity sensor 62 . Proximity sensor 62 may be any type of sensor, transducer, motion detector or the like that can sense or indicate whether paper 28 is within sensing or detecting area 66 . In one form, proximity sensor 62 is an ultrasonic generator/transducer such as a SUPERPROX® proximity sensor manufactured by Hyde Park Electronics, Inc. of Dayton, Ohio. Proximity sensor 62 is adjusted such that only material within sensing or detecting area 66 generates a material sensed or detected signal. With additional reference to FIG. 3, proximity sensor 50 is in communication with controller 82 via line 64 . Controller 82 is in communication with air supply system 80 via line 84 . Air supply system 80 is coupled via conduit 96 to air valve or solenoid 94 that is coupled to conduit 60 associated with nozzles 92 of blowpipe 58 . Controller 82 is in communication with solenoid 94 via line 98 for activation and deactivation, or on/off, control thereof. When solenoid 94 is actuated by controller 82 via line 98 in accordance with the present invention, compressed or pressurized air is caused to flow from air supply system 80 through conduit 96 and into nozzles 92 of blowpipe 58 . Of course, when solenoid 94 is deactivated or turned off, the air flow into blowpipe 58 is ceased.
In like manner to threading doctor assemblies 30 a and 32 b depicted in FIG. 2, threading doctor assemblies 30 b, 30 c, 30 d, 30 e, 32 a, 32 c, 32 d, and 32 e each include a blowpipe having air nozzles in air communication with an air valve or solenoid that is in air communication with air supply system 80 , and a proximity sensor in communication with controller 82 . Each solenoid is in communication with the controller 82 . This is indicated by the several partial blowpipes depicted in FIG. 3 which represent a plurality of threading doctor assemblies in accordance with the present invention.
In operation, fiber web material 28 initially enters dryer group 10 and, in particular, lower dryer group 14 between lower felt 26 coming from lower felt guide roll 24 b and lower dryer cylinder 22 a traveling in the direction indicated by arrow 38 . Fiber web material 28 is compressed against lower dryer cylinder 22 a between lower felt 26 and the outer surface of the lower portion of lower dryer cylinder 22 a, then exits on the opposite side of lower dryer cylinder 22 a towards upper dryer cylinder 16 a. At upper dryer cylinder 16 a, fiber web material 28 becomes compressed against upper dryer cylinder 16 a between upper felt 20 and the outer surface of the upper portion of upper dryer cylinder 16 a. This compression scheme of the fiber web material between alternating lower and upper dryer cylinders continues until the fiber web material exits from the last dryer cylinder, here upper dryer cylinder 16 e. In order to direct the fiber web material into the convergence area or entry point, defined as between the particular upper or lower felt and the particular upper or lower respective dryer cylinder, pressurized air from air supply 80 is directed through the blowpipe associated with the particular dryer cylinder.
Generally, before leading tail 40 of fiber web material 28 enters the first dryer cylinder, here lower dryer cylinder 22 a, controller 82 activates at least the threading doctor blowpipe associated with that cylinder, and preferably, the next one (1) or two (2) blowpipes in the fiber web material advancing direction. All other threading doctor blowpipes are not active since the solenoids associated therewith are off or deactivated. With reference to FIG. 2, as leading tail 40 of fiber web material 28 rolls off of upper dryer cylinder 16 a into emergence area 70 and begins to travel downwardly, proximity sensor 50 determines that leading tail 40 has entered sensing area 54 . Proximity sensor 50 then sends a signal to controller 82 via line 52 . As indicated above, controller 82 has preferably already activated solenoid 76 such that air from air supply system 80 is already flowing into blowpipe 46 and thus from nozzles 86 . However, in accordance with an alternative approach, the moment proximity sensor 50 detects leading tail 40 within sensing area 54 , sensor 50 indicates such presence to controller 82 which signals solenoid 76 , via line 90 , to activate and allow air to flow into blowpipe 46 .
As leading tail 40 emerges from emergence area 74 into sensing or detecting area 66 , proximity sensor 62 of threading doctor 32 b detects the presence of leading tail 40 . Proximity sensor then generates and sends a detection signal via line 64 to controller 82 . Upon receipt of the detection signal from proximity sensor 62 , controller 82 activates the solenoids of the next two ( 30 b, and 32 c ) or three ( 30 b, 32 c, and 30 c ) threading doctors in the paper advance direction. As well, controller 82 sends a signal via respective lines to deactivate the solenoids of any threading doctors which are previous or behind, relative to the fiber web material advance direction, more than two or three threading doctors before proximity sensor 62 . In this manner, controller 82 sequences the activation and deactivation of threading doctors as the leading tail of the fiber web material advances.
In another form, it is possible to utilize a single proximity sensor disposed at the first or second threading doctor, or several proximity sensors disposed on the beginning several threading doctors, to detect when the leading tail of the paper enters the system. Since the rotational velocity of the dryer cylinders is generally known, the controller can be programmed or determine on the fly with the aid of one or more rotational velocity sensors, when to activate the next blowpipes of the threading doctors as the fiber web material advances, and as well determine when to deactivate any preceding blowpipes that were activated.
While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.
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This invention is directed to a paper-making machine utilizing rotating cylinders, especially dryer cylinders, with a drying felt intertwined about the dryer cylinders to compress the wet paper against the dryer cylinders as the wet paper travels therealong. A threading doctor assembly with a blowpipe air nozzle blowing system is associated with each dryer cylinder. When air is flowing into the blowpipe blowing system, the leading tail of the wet paper is directed from the preceding dryer cylinder to the next. A proximity sensor associated with each threading doctor assembly is in communication with a controller and is positioned to determine if the wet paper is within a detection area. Air valves or solenoids coupled between an air supply system and the blowpipes are also coupled to the controller. As the leading tail of the paper is detected by a proximity sensor to be within the detection area, the next several solenoids associated with the next several threading doctors in the paper advance direction are activated. As well, solenoids associated with the blowpipes of the threading doctors that are more than two or three behind the proximity sensor, relative to the paper advance direction are deactivated. Such sequencing of blowpipes as the leading tail advances through the system reduces the air supply pressure necessary for the system.
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[0001] The present disclosure relates to subject matter contained in priority Korean Application No. 10-2003-0063542, filed on Sep. 15, 2003, which is herein expressly incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a reinforced slide chassis structure of an audio/video system, more particularly, to a reinforced slide chassis structure of an audio/video system for a vehicle, mounted with a reinforcing bracket formed in a direction of a long hole of the slide chassis.
[0004] 2. Description of the Related Art
[0005] As more luxurious cars become popular among people, a variety of luxurious in-vehicle options are being introduced. Among the options are communication devices that provide drivers to access every kind of information, such as continually updated traffic information, road information, and map to a destination. One of typical examples is an audio/video system (hereinafter it is referred to as an ‘AV system’) for a vehicle mounted with a device for watching TV or an automatic navigation system.
[0006] In general, a front panel of such AV system forms a monitor, and a cassette player or compact disk player of a car audio is housed in the front panel. Therefore, when a driver wants to watch the monitor or change a cassette tape in the cassette player, the monitor is tilted at a designated angle.
[0007] An AV system comprising this type of monitor tilting apparatus was disclosed in Korean Patent Publication No. 2002-0006075 and Korean Utility Model Publication No. 2000-0011042.
[0008] An AV system with an existing monitor tilting apparatus is depicted in FIGS. 1 through 5 . More specifically, FIG. 1 is a perspective view of a related art AV system with a monitor tilting apparatus, FIG. 2 is a perspective view of the monitor in FIG. 1 , in which the monitor is being tilted, FIG. 3 is a perspective view of a low-surface chassis of FIG. 2 , FIG. 4 is a cross-sectional view taken along line A-A in FIG. 3 , and FIG. 5 is a cross-sectional view taken along line B-B in FIG. 3 .
[0009] As shown in FIGS. 1 and 2 , the AV system having an existing monitor tilting apparatus includes a main body 10 that is built in a cartridge of the body of a car. On a front surface of the main body 10 is a monitor 15 , which is tiltable.
[0010] On the low-surface chassis 20 disposed at a lower end of the main body 10 is a slide chassis 30 , as depicted in FIG. 3 , through which the monitor 15 can move back and forth. At this time, a lower end of the monitor 15 is connected to a monitor mounting part 38 of the slide chassis 30 .
[0011] Meanwhile, a long hole 35 is formed on the slide chassis 30 back and forth, enabling a motor part 50 and a back-and-forth motion member 60 to be mounted on the low-surface chassis 20 . A support bar 21 is placed on the low-surface chassis around the hole 35 formed on the slide chassis 30 , and a main printed circuit board 11 is mounted on the support bar 21 , being inside out. As shown in FIG. 4 , on the support bar 21 is the motor part 50 including a motor 53 and a worm 55 . The main printed circuit board 11 has a plurality of control means for the motor part 50 . The worm 55 of the motor part 50 is engaged (or meshed) with a wormwheel 61 , and the wormwheel 61 is engaged with a wheel 63 . Shafts of the wheel 63 and the wormwheel 61 are mounted on the low-surface chassis 20 . The wheel 63 is again engaged with a rack gear part 37 of the slide chassis 30 .
[0012] As shown in FIG. 5 , there is a plurality of guide shafts 21 fixed on the right and left sides of the low-surface chassis, and guide rollers 23 are positioned centering around the guide shafts 21 . Also, long holes 31 are formed on the slide chassis 30 centering around the guide rollers 23 in such a manner that when the slide chassis 30 moves, the long holes 31 move back and forth with respect to the guide rollers 23 . In short, the guide rollers 23 , as their name implies, play as a guide for the slide chassis 30 .
[0013] However, the AV system with the above monitor tilting apparatus poses a problem.
[0014] For instance, the long hole 31 of the slide chassis 30 is easily deformed or twisted in spite of using a 1.2 mm-thick material to prevent vibration and deformation of the slide chassis 30 .
[0015] This deformation of the long hole 31 of the slide chassis 30 is in fact common for all existing AV systems.
SUMMARY OF THE INVENTION
[0016] It is, therefore, an object of the present invention to provide a reinforced slide chassis structure of an audio/video system for a vehicle to prevent deteriorations in the slide chassis by reinforcing a deformation-sensitive part of the slide chassis while maintaining a thickness of the entire slide chassis, whereby a weak long hole area can be reinforced and the weight of the whole of the slide chassis can be reduced.
[0017] Another object of the present invention is to provide a reinforced slide chassis structure of an audio/video system for a vehicle, which is easy to guide and assemble.
[0018] To achieve the above object, there is provided a reinforced slide chassis structure of an AV system for a motor vehicle with a tiltable monitor disposed at a front surface of a main chassis, the reinforced slide chassis structure including: a low-surface chassis disposed at a lower end of the main chassis; and a slide chassis mounted on the low-surface chassis, moving a lower side of the monitor back and forth, wherein at least one reinforcing bracket is mounted on the slide chassis.
[0019] Also, the reinforcing bracket is formed along with a long hole formed on the slide chassis.
[0020] According to the above structure, the thickness of the entire slide chassis can be maintained, and only the relatively weak long hole area is reinforced..
[0021] In this manner, it is possible to reduce the weight of the entire slide chassis, while preventing deteriorations in the slide chassis by reinforcing a deformation-sensitive portion out of the slide chassis.
[0022] Besides, drilling an assembly hole into the reinforcing bracket, a driver can change diverse parts more easily ad conveniently, simply by inserting a tool to the assembly hole to loosen or fasten a blot of a guide shaft. Since the reinforcing bracket needs not to be separated from the slide chassis, the convenience and assembability are improved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The above objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which:
[0024] FIG. 1 is a perspective view of a related art AV system with a monitor tilting apparatus;
[0025] FIG. 2 is a perspective view of the monitor in FIG. 1 , in which the monitor is being tilted;
[0026] FIG. 3 is a perspective view of a low-surface chassis of FIG. 2 ;
[0027] FIG. 4 is a cross-sectional view taken along line A-A in FIG. 3 ;
[0028] FIG. 5 is a cross-sectional view taken along line B-B in FIG. 3 ;
[0029] FIG. 6 is a perspective view of a driving assembly in an AV system according to a preferred embodiment of the present invention;
[0030] FIG. 7 is an enlarged side view of a motor part and a back-and-forth motion member in FIG. 6 ; and
[0031] FIG. 8 is a cross-sectional view taken along with line C-C in FIG. 7 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0032] A preferred embodiment of the present invention will be described herein below with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.
[0033] FIG. 6 is a perspective view of a driving assembly in an AV system according to a preferred embodiment of the present invention, FIG. 7 is an enlarged side view of a motor part and a back-and-forth motion member in FIG. 6 , and FIG. 8 is a cross-sectional view taken along with line C-C in FIG. 7 .
[0034] As depicted in FIG. 6 , the driving assembly for a vehicle AV system having a tiltable monitor disposed at a front surface of a main body of the AV system includes a low-surface chassis 200 positioned at a lower end of the main chassis 100 , and a slide chassis 300 mounted on the low-surface chassis 200 , for moving a lower side of the monitor (not shown) back and forth.
[0035] As mentioned before, the monitor (not shown) is disposed at the front surface of the main body 100 , and a main printed circuit board 110 is housed in the main body 100 .
[0036] One thing to be aware of in FIG. 6 is that to show inside of the main body 100 , the front surface 100 a of the main body 110 is upside down in the drawing.
[0037] The main printed circuit board 100 has diverse parts for controlling a motor part 500 , and a cable 130 connected to a connector 150 .
[0038] Also, a plurality of guide shafts 210 are fixed in the right and left sides of the low-surface chassis 200 .
[0039] As FIG. 8 illustrates, a fastening hole (not shown) to which a bolt 270 is inserted is formed on a top end of the respective guide shafts 210 , and guide rollers 230 for guiding the slide chassis 300 are installed, centering around the guide shafts 210 .
[0040] On the slide chassis 300 is a long hole 310 to which guide rollers 230 are inserted, enabling the slide chassis 300 to move back and forth.
[0041] As such, guide rollers 230 of the guide shafts 210 fasted onto the low-surface chassis 200 are inserted to the long hole 310 of the slide chassis 300 , and thus, the guide shafts 210 are protruded to the long hole 310 . A washer 250 is mounted on the respective guide shafts 210 , to inhibit the guide roller 230 from derailing, and then the bolt 270 is inserted to the fastening hole of the guide shaft 210 .
[0042] Both ends of the slide chassis 300 are monitor mounting parts 380 on which the lower end of the monitor is placed.
[0043] A long hole 350 is formed on a central portion of the slide chassis 300 in such a manner that the motor part 500 and the back-and-forth motion member 600 can be mounted on the low-surface chassis 200 .
[0044] As illustrated in FIG. 7 , the motor part 500 includes a motor 530 , a printed circuit board 400 attached to one end of the motor 530 , and a worm 550 attached to the other end of the motor 530 , transferring power from the motor 530 to the back-and-forth motion member 600 .
[0045] Specifically, the printed circuit board 400 is fastened on the low-surface chassis 200 , and the motor 530 is attached to the printed circuit board 400 . One side of the printed circuit board 400 is a connecter 510 .
[0046] The worm 500 is attached to a motor shaft 530 a, and it rotates as the motor 530 starts driving.
[0047] In the meantime, there is a bracket 410 attached to the motor 530 , to support the low surface of the motor 530 and the motor shaft 530 a. Thanks to this bracket 410 , the motor 530 is more firmly fastened on the printed circuit board 400 .
[0048] The back-and-forth motion member 600 includes a wormwheel 610 , which is engaged with a worm 550 , and a wheel 630 , one end thereof being engaged with the wormwheel 610 and the other end being engaged with the slide chassis 300 .
[0049] More specifically speaking, the wormwheel 610 constitutes a head 613 and a body 615 , each having gear teeth. And, a shaft at the center of the wormwheel 610 is mounted on the low-surface chassis 200 .
[0050] Similar to the wormwheel 610 , the wheel also constitutes a head 633 and a body 635 , each having gear teeth. And, a shaft at the center of the wheel 630 is mounted on the low-surface chassis 200 .
[0051] The head 633 of the wheel is engaged with the body 615 of the wormwheel 610 .
[0052] The body 635 of the wheel is engaged with a rack gear part 370 that is formed on the slide chassis 300 in a direction of the slide chassis' motion.
[0053] Preferably, a “⊂”-shaped reinforcing bracket 390 is formed along the long hole 310 formed on the slide chassis 300 . This reinforcing bracket 390 is fastened onto the slide chassis by means of a plurality of fastening means 390 a, e.g. bolts.
[0054] Also, an assembly hole 391 can be drilled into the reinforcing bracket 390 , particularly where the guide shafts 210 are mounted.
[0055] An operation of the embodiment having the above structure is now discussed below.
[0056] As for tilting the monitor, a vehicle driver presses a switch to drive the motor part 500 . Then the wormwheel 610 of the motor 530 starts rotating, and the wormwheel 610 being perpendicularly meshed (or engaged) with the wheel 630 starts rotating. Since this wormwheel 610 is engaged with the wheel 630 , the wheel 630 also starts rotating. At this time, because the wheel 630 has a larger diameter than that of the wormwheel 610 , it plays as a reduction gear, reducing the speed.
[0057] To be short, as the wheel 630 rotates, the rack gear part 370 of the slide chassis 300 being engaged with the wheel 630 makes a straight-line motion to the front, and thus, the slide chassis 300 moves forward.
[0058] On the other hand, if the driver presses the switch one more time, the motor shaft 530 rotates in a reverse direction, and the wormwheel 610 also rotates in a reverse direction of the above. As a result, the wormwheel 610 and the wheel 630 rotate in a reverse direction of the above, and the rack gear part 370 of the slide chassis 300 moves backward.
[0059] At this time, the guide roller 230 of the guide shaft 210 fastened onto the low-surface chassis 200 acts as a guide for guiding the back-and-forth motion of the slide chassis 300 .
[0060] With an application of the reinforcing bracket 390 to the slide chassis 300 moving along the long hole, the relatively weak long hole area out of the slide chassis 300 can be strengthened.
[0061] That is to say, without changing the thickness, i.e. approximately 0.8 mm, of the entire slide chassis 300 , it is possible to reinforce the relatively weak long hole area 310 .
[0062] In this manner, deteriorations in the slide chassis 300 can be prevented by reducing a total weight of the slide chassis 300 yet reinforcing the deformation-sensitive portion.
[0063] Moreover, if the assembly hole 391 is drilled into a position where the guide shaft 210 of the reinforcing bracket 390 is supposed to be attached, the driver can easily change the washer 250 , the guide shafts 210 and the guide rollers 230 and so forth, by inserting a tool to the assembly hole 391 to loose or fasten a bolt. Overall, drivers can easily change parts with new ones, not necessarily separating the reinforcing bracket 390 from the slide chassis 300 .
[0064] In conclusion, the reinforced slide chassis structure of an AV system for the vehicle has the following advantages.
[0065] First, since the reinforcing bracket is installed along the long hole of the slide chassis, the relatively weak long hole area can be strengthened, while the thickness of the entire slide chassis being maintained.
[0066] Therefore, deteriorations in the slide chassis can be prevented by reducing a total weight of the slide chassis yet reinforcing the deformation-sensitive portion.
[0067] Second, drilling the assembly hole into where the guide shaft of the reinforcing bracket is supposed to be attached, the driver can easily change the washer, the guide shafts and the guide rollers and so forth, simply by inserting a tool to the assembly hole to loose or fasten a bolt. Overall, drivers can easily change diverse parts with new ones, not necessarily separating the reinforcing bracket from the slide chassis, and as a result, the convenience and assembability of the invention can be improved.
[0068] While the invention has been described in conjunction with various embodiments, they are illustrative only. Accordingly, many alternative, modifications and variations will be apparent to persons skilled in the art in light of the foregoing detailed description. The foregoing description is intended to embrace all such alternatives and variations falling with the spirit and broad scope of the appended claims.
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The present invention relates to a reinforced slide chassis structure of an audio/video system, more particularly, to a reinforced slide chassis structure of an audio/video system for a motor vehicle, capable of preventing deteriorations in the slide chassis by reducing a total weight of the slide chassis yet reinforcing a deformation-sensitive portion of the slide chassis.
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BACKGROUND OF THE INVENTION
This invention relates to a device for automatically lapping valve seats and more particularly to such a device suitable for repairing main steam valves and the like used in atmospheres highly contaminated with radioactive substances in nuclear power plants or the like.
Nuclear power plants are subject to legal periodic inspections at predetermined time intervals. Under these circumstances it is frequently required to lap valve seats upon repairing main steam isolation valves and other valves. The lapping operation has be previously necessary to be manually performed. Therefore after a radiation level within the particular nuclear reactor has been reduced to its permissible value or less, repair personnels are usually entered into that nuclear reactor to perform the operation of lapping valve seats within a time interval as short as possible. It has been previously said that a radiation dose of each operation is inversely proportional to the square of a distance from a contamination source involved and also such a radiation dose is proportional to his or her working hours. Therefore the same operator can not work for a long time and the exposure dose of the operator restricts his or her working hours. This has unavoidably led to the shift of repair personnels after short working hours in view of the control of their health and accordingly to the necessity of securing many experts.
On the other hand, devices for lapping valve seats have been previously proposed. Most of the proposed lapping device have been of the manually operated type although some of the devices have been of the power operated type. In either type of conventional lapping devices a valve seat to be lapped has been coated with a lapping agent and centered on the lapping plate. Then the lapping plate has been rotated with a predetermined rotational force and with respect to the valve seat thereby to lap the latter through the lapping agent. However those devices have been of such a structure that a pressure applied to the interface of the valve seat and lapping plate is maintained at a predetermined fixed magnitude and can be adjusted in accordance with the area of the particular valve seat and that for each cycle of the lapping operation the lapping agent is applied to the valve seat being lapped or the next valve seat after the removal of the lapping plate. It is desirable to prove a device for automatically lapping valve seats operated at a remote position. This is particularly desirable for lapping valve seats used in the nuclear reactor because jobs performed within the reactor are not desirable in view of the health of the operators.
SUMMARY OF THE INVENTION
Accordingly it is an object of the present invention to provide a new and improved device for automatically lapping valve seats which apparatus is possible to be operated at a remote position and eliminates the necessity of performing the operation within the associated nuclear reactor.
The present invention accomplishes this object by the provision of a lapping device for automatically lapping a valve seat, comprising, in combination, a supporting plate for securing the device to a valve body including a valve seat to be lapped a sleeve member pendent from the central portion of the supporting plate, a hollow driven shaft extending through both the supporting plate and the sleeve member to have one end portion slighly projecting beyond the supporting plate and the other end portion projecting beyond the sleeve member, fluid operated cylinder means disposed in the sleeve member on that side remote from the supporting plate, a piston member disposed on the driven shaft to cooperate with the cylinder means to longitudinally move the driven shaft, a lapping plate attached to the extremity of the other end portion of the driven shaft and including a peripheral edge capable of being intimately contacted by the valve seat through the longitudinal movement of the driven shaft when the supporting plate is positioned on the valve body, driving means for driving the drived shaft along with the lapping plate, and automatic supply means disposed on the lapping plate to automatically supply a lapping agent to the peripheral edge of the lapping plate.
BRIEF DESCRIPTION OF THE DRAWING
The present invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawing in which a single FIGURE is a longitudinal sectional view, partly in elevation of a device for automatically lapping a valve seat constructed in accordance with the principles of the present invention and operatively coupled to a valve body.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawing, there is illustrated a device for automatically lapping valve seat constructed in accordance with the principles of the present invention which device is suitable for lapping the valve seat of the main steam isolation valve within containers having housed therein nuclear reactors high in radiation dose. The arrangement illustrated comprises a main frame generally designated by the reference numeral 1 including a supporting disc 2 and a sleeve member 3 formed integrally with the supporting disc 2 to extend from the central portion of the lower surface as viewed in the drawing of the supporting disc 2 and substantially perpendicularly to the latter. A hollow driven shaft 4 extends through the center of the supporting disc 2 and also coaxially through the sleeve member 3 and supported by both the supporting disc 2 and intermediate portions of the sleeve member 3 for both rotational movement and longitudinally sliding movement. The driven shaft 4 has one end portion slightly projecting beyond the supporting disc 2 and the other end portion projecting beyond that end remote from the supporting disc 2 or the lower end of the sleeve member 3. Then a lapping plate 5 in the form of a disc is fixedly secured to the extremity of the other end portion of the driven shaft to be substantially perpendicular to the axis of the shaft 4.
The sleeve member 3 is provided on that side remote from the supporting disc 2 with a pneumatic cylinder 6 within which a piston 7 is slidably disposed. The piston 7 is shown in the drawing as being formed of that portion of the hollow shaft 4 located within the cylinder 6 and large in diameter. The piston 7 may be formed of an annular member fitted onto and fixed to the shaft 4. Then a compression spring 8 is disposed around the driven shaft 4 between the piston 7 and the lower end as viewed in the drawing of the cylinder 6 within the latter. The spring 8 serves normally to maintain the lapping plate 5 at a predetermined distance from the supporting disc 2 as will be described hereinafter.
In order to drive the driven shaft 4, an electric reversible motor 10 is fixedly secured to the outer or upper surface of the supporting disc 2 and operatively connected to a speed change gearing 10 disposed in that portion of the disc 2 located below the motor 9. Then the gearing 10 is operatively connected to a sprocket wheel 11 subsequently coupled by an endless chain 12 (only one portion of which is illustrated) to another sprocket wheel 13 mounted on the shaft 4. Thus motor 9 forms driving means for the driven shaft 4 along with the components 10 through 13 to transmit a torque to the shaft 4.
The lapping plate 5 has a lower peripheral edge as viewed in the drawing bevelled to form a working surface 14 complementary in configuration to the desired valve seat and a guide ring 15 detachably secured to the lower surface thereof. Further the lapping plate 5 is provided on the upper surface with supply means 16 for automatically supplying a lapping agent and a cleaning wiper 17. More specifically, the supply means 16 is composed of a syringe obliquely fixed to the peripheral portion of the lapping plate 5 to open at that portion of the lower plate 5 surface adjacent to the lower end as viewed in the drawing of the bevelled working surface 14. The cleaning wiper 17 is suitably supported to the lapping plate 5 to radially outwardly extend therethrough. The wiper 17 includes a pneumatic small-sized cylinder, a piston rod with a forked end extensible from the cylinder and a stack 18 of circular wiping laminations of fibrous material carried by the forked end of the piston rod.
As shown, a periscope type observation glass 19 coaxially extends through the hollow driven shaft 4 and has an upper end slightly projecting beyond the adjacent end of the shaft 4. The lower portion of the observation glass 19 projecting beyond the lapping plate 5 is bent in a direction substantially parallel to the lapping plate 5 and has an end 20 reaching adjacent the periphery of the plate 5.
The arrangement thus far described is shown in the drawing as being operatively connected to a valve box B including a valve seat S to be lapped with an associated valve removed from the valve body. The supporting disc 2 rests on the upper end of the valve body B. A centering ring 21 is detachably secured to the lower surface thereof. The centering ring 12 is fitted into an associated peripheral groove formed on the upper end of the valve body B with a predetermined tolerance to cause the center of the lapping plate 5 to coincide with that of the valve seat by the aid of the guide ring 15 on the lapping plate 5. Thereafter the arrangement is fixedly secured to the valve body B by means of clamping means including an annular permanent magnet 22 snugly fitted onto the supporting disc 2. Under these circumstances, the lapping plate 5 is located at its predetermined position where it is positioned short of the valve seat S. Then the lapping plate 5 can be slightly moved toward the valve seat S axially of the shaft 4 until the working surface 14 thereof engages the latter.
In order to effect this slight axial movement of the lapping plate 5, a suitable fluid under pressure such as air or nitrogen gas is introduced into the upper end of the cylinder 6 through a fluid feed mechanism as schematically shown by the arrow a 1 to downwardly push the piston 7 against the action of the compression spring 8. Thus the driven shaft 4 and hence the lapping plate 5 is moved downwardly until the working surface 14 of the plate 5 is brought into intimate contact with the valve seat S.
Under these circumstances, an electromagnetic valve or an adjusting valve (not shown) disposed within the fluid supply mechanism a 1 can be operated to control the pressure of the fluid within the cylinder 6 thereby to control a surface pressure under which the working surface 14 of the fitting plate 5 pushes against the valve seat S to any desired value.
While the lapping plate 5 pushes against the valve seat S under the required pressure as above described, the reversible motor 9 is energized to drive the driving shaft 4 and therefore the lapping plate 5 in either of the opposite directions through the speed change gearing 10, the sprocket wheel 11, the endless chain 12 and the sprocket wheel 13. At the same time a pressurized fluid is supplied to the lapping agent supply means 16 through a fluid feed mechanism as schematically shown by the arrow a 2 to inject a lapping agent included therein at the interface of the working surface 14 of the lapping plate 5 and the valve seat S. Thus the valve seat S is lapped by the working surface 14 while the lapping agent is supplied to the interface of the two components 14 and S.
The rotational speed of the lapping plate 5 can be changed by the operation of the speed change gearing 10. If the speed change gearing 10 can change continuously the change gear ratio thereof then the rotational speed of the lapping plate can be varied in stepless manner.
The pressurized fluid supplied to the supply means 16 may be the same as the fluid introduced into the cylinder 6 and the pressure thereof can be controlled by an electromagnetic valve or the like (not shown) disposed in the fluid feed mechanism a 2 .
After the completion of the lapping operation or in the lapping operation, the motor 9 can be deenergized to stop the lapping plate 5 and then the driven shaft 4 with the lapping plate 5 is raised to separate the working surface 14 of the lapping plate 5 away from the valve seat S through the combined operation of the cylinder, piston and spring 6, 7 and 8 respectively. Following this a pressurized fluid is supplied to the cylinder of cleaning wiper 17 through a fluid feed mechanism as schematically shown by the arrow a 3 in the drawing. This causes the wiping stack 18 to push against the valve seat S. Simultaneously the lapping plate 5 is rotated through the energization of the motor 9 while a liquid cleaner is intermittently or continuously spouted on the valve seat S thereby to cause the stack 18 to wipe and clean the entire area of the valve seat S. Thereafter the wiping stack 18 is retracted to its original position.
The wiper 17 may be preferably constructed so that the wiping stack 18 is rotated through a predetermined angle, for example, one eighth of one complete rotation thereof for each complete rotation of the lapping plate 5. Also movements associated with the reciprocating movement of the wiping stack 18 may be effected by the operation of the cylinder disposed in the wiper 17.
After the completion of the lapping operation, one can observe the lapped valve seat through the observation glass 19 to determine if the lapped valve seat is acceptable. If desired, a photographic camera (not shown) may be operatively coupled to the observation glass 19 to photograph the status of a valve seat before and after the particular lapping operation. Alternatively, as shown in the drawing, a television pickup camera 23 high in resolution may be operatively connected to the upper end of the observation glass 19 for the purpose of reproducing and observing the lapped status of the particular valve seat through the associated television receiver at a remote position. The pickup camera 23 may be also operatively coupled to the observation glass 19 through a fibre optics (not shown).
From the foregoing it will be appreciated that the operation of the lapping device according to the present invention is controlled by electrical and/or pressurized fluid means. Therefore the operator can operate any suitable operation board disposed at a remote position to perform all the necessary operations required for lapping valve seats without directly touching the device. Also the operation board can be provided with a television set to always monitor the lapping operations. Therefore it is possible to avoid a danger that the operator may be exposed to radiation. Further the present invention is extremely advantageous in view of the economy because of the elimination of the necessity of performing the mannual operation requiring many shift operators. In addition, the use of magnetically clamping means permits the one-step operation of fixing the device to a valve body without performing any operation requiring to touch the components, such as bolting.
While the present invention has been illustrated and discribed in conjunction with a single preferred embodiment thereof it is to be understood that various changes and modifications may be resorted to without departing from the spirit and scope of the present invention.
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The disclosed device comprises a supporting disc, a sleeve centrally pendent from the disc, a hollow driven shaft rotatably and axially slidably extending through the disc and sleeve, and a lapping disc fixed to that end of the shaft extending from the sleeve. With the supporting disc disposed upon a valve body including a valve seat to be lapped, the lapping disc can contact the valve seat to fit it during the rotation of the shaft. With the lapping disc raised from the lapped valve seat, a wiper on the disc is actuated to wipe the latter. The seat can be observed through a periscope type observation glass extending through the hollow shaft.
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This application is a 371 of PCT/JP02/12577, filed on 2 Dec. 2002.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is related to sanitary paper such as facial tissues.
2. Description of the Related Art
Recently, so-called luxury type facial tissues have come onto the market which touch softly on the skin by containing a solution such as softener in the tissues. These tissues have become popular as it hardly stings the skin by blowing one's nose, or makes the nose to turn reddish.
However, usual sanitary paper which contains a solution could not prevent the sting and the redness of the skin sufficiently.
Thus, our diligent effort revealed that when usual sanitary paper with a solution touches the corneal surface, the sheet removes the sebum of the surface. Therefore, when the sanitary paper touches the same part of the skin frequently, the sebum will be removed first by the sanitary paper and then, at the place where the sebum was removed, the moisture inside the corneum will be removed. Accordingly, the skin will become rough and will turn reddish.
SUMMARY OF THE INVENTION
The major object of the present invention is to provide sanitary paper which is excellent in touch onto skin such as moistness and softness and which does not sting and make the skin reddish even if the sanitary paper touches the skin frequently.
The above-mentioned object can be attained by the sanitary paper of the present invention which comprises a paper base which contains a solution, in which an oil absorbance is 7.0 mm or less. The oil absorbance mentioned in the present invention is measured, under the standard condition which is regulated by Japanese Industrial Standard P8111, according to the Klemm water absorbance test which is regulated by Japanese Industrial Standard P8141, where water is replaced with cooking oil on the market (made by THE NISSHIN OIL MILLS, LTD.). However, measuring time length is 60 seconds and the flow of the paper is longitudinal way (which is the way of manufacturing line flow). That is, a specimen of the sanitary paper is put in a longitudinal way, the lower edge of the paper is dunked into the cooking oil, the height of the rising the cooking oil is measured 60 seconds later and is regarded as the mean value often points of the specimen.
Usual sanitary paper, on which a solution was applied, has a character of oil absorption which is too high and, as shown in FIG. 1( a ), when usual sanitary paper and the skin touch each other frequently, the sebum of corneal surface, and then, the moisture inside the corneum will be removed. As a result, the skin will become rough and will turn reddish.
On the other hand, according to the present invention, when the oil absorbance is 7.0 mm or less, it will be difficult to remove the sebum of corneal surface by a sanitary paper as shown in FIG. 1( b ), and therefore the moisture inside the corneum will be preserved. As a result, the skin will not become rough or reddish easily.
According to the present invention, sanitary paper is proposed in which a moisture content of the sanitary paper is 9.50 to 15.00%, determined in accordance with Japanese Industrial Standard P8127, after controlling the humidity of the sanitary paper under the condition that is regulated by Japanese Industrial Standard P8111.
The usual product on the market has a low moisture content. Unlike this, the present invention having an elevated moisture content gives an excellent touch onto skin which is realized mainly as a satisfactory moistness. In addition, even if there is not much seburn of corneal surface when the sanitary paper touches the skin, it will be difficult to remove the moisture inside the corneuxn. Therefore, even if the sanitary paper touches the skin frequently, the skin will not become rough or reddish easily.
According to the sanitary paper of the present invention, it is preferable that the solution content per unit volume of a paper base is 46.0 to 160.0 mg/cm 3 . By employing the solution specified above, the oil absorbance of the sanitary paper can be in the range 7.0 mm or less. When the solution content becomes more than 160.0 mg/cm 3 , the sanitary paper will show a sticky feeling and will give the users an unpleasant feeling.
According to the sanitary paper of the present invention, the solution is preferably a slightly acid solution that is pH 5.0 to 6.0. By keeping the pH of the solution at a slightly acidic level similar to that of a healthy skin, the skin will not turn into alkaline or strongly acidic even when the sanitary paper touches the skin. Accordingly, it will prevent the skin effectively from being made rough by the pH of the solution.
Further, according to the sanitary paper of the present invention, it is preferable that the solution contains at least one of moisturizers selected from polyhydric alcohols such as glycerin and propylene glycol, or saccharides such as sorbitol and glucose, or glycol-based solvents or derivatives thereof. By using such solutions, the sanitary paper may have a rich moisture and an excellent moistness.
Further, according to the sanitary paper of the present invention, it is preferable that the solution contains at least one of softeners selected from anionic surfactant or nonionic surfactant or cationic surfactant or zwitterionic surfactant. By using such solution, the sanitary paper may have an excellent softness.
Further, according to the sanitary paper of the present invention, it is preferable that the solution contains at least one of antioxidants selected from vitamin C and vitamin E. Vitamin C or vitamin E is suitable for the antioxidant in the present invention. Vitamin E is an ingredient which has a strong reducing force and possesses an antioxidant action such as elimination of activated oxygen-free radical and a prevention of the generation of lipid peroxide. Accordingly, vitamin E will work as a stabilizer of the solution and also when the sanitary paper is given to the skin of the user, it will exhibit an oxidization prevention effect and a circulation of the blood promotion effect onto the sebum of the skin. Vitamin E also possesses a moisture preservation function. On the other hand, vitamin C has an antioxidant action on sebum, as same as vitamin E. As vitamin C acts to reduce vitamin E, when vitamin C and vitamin E both are used together, vitamin C works as a promoter of vitamin E, in which vitamin C reduces the vitamin E which was oxidized by activated oxygen and such, and maintains the strong antioxidant action on sebum of vitamin E.
Further, according to the sanitary paper of the present invention, it is preferable that the solution contains a collagen. 90% of the dermis is formed by collagen and if the collagen decreases, the skin will lose their moisture and fitness. Therefore, by incorporating the collagen into the sanitary paper, moisturizing effect on the ski will be exhibited upon contact with a skin, as well as a moisturizing effect also on the sanitary paper.
Further, according to the sanitary paper of the present invention, it is preferable that the bending hardness B of the sanitary paper is 0.0040 to 0.0060 g.multidot.cm 2 /cm, determined by using a pure bending tester. The bending hardness B of the present invention is described in below. A 20 cm wide paper specimen, having a 1 cm chuck interval, is betided by pure bending way, a bending way which always maintains one side of the paper in an ext. First, bend it toward the front side till the maximum curvature reaches 2.5 cm −1 and put it back to the origin, and next, bend it toward the backside till the maximum curvature reaches −2.5 cm −1 and put it back to the origin. At this moment, in the relation between curvature and bending moment the bending hardness B of the present invention is indicated as an average inclination between curvature 0.5 and 1.5 cm −1 .
The bending hardness B of a usual product on the market is high. On the other hand, when the bending hardness B is reduced according to the present invention, the sanitary paper will be excellent in touch onto skin because of mainly the softness. Moreover, when the paper base is impregnated with moisturizer or softener, there will be an advantage that moistness or softness will be promoted.
Further, according to the sanitary paper of the present invention, it is preferable that the softness per basis weight of the sanitary paper is 5.4 to 6.4 m 2 /100. As used herein, the term “softness” denotes a value of resistance (a mean value of lengthwise and widthwise values) when a 10 cm wide paper is pushed into a 5.0 mm wide crevice by a terminal. Also, basis weight is a value determined in accordance with Japanese Industrial Standard P8124, The value of softness of usual product on the market was too high. When the value of softness is in the low range according to the present invention, the sanitary paper will be excellent in softness.
Further, according to the sanitary paper of the present invention, it is preferable that the basis weight per 1-ply tissues is 10 to 35 g/m 2 and the sanitary paper consists of 1 to 3-ply tissues, a lengthwise tensile strength in a dry condition is 60 to 160 N/m, a crosswise tensile strength in a dry condition is 20 to 60 N/m, and the ratio of the crosswise tensile strength to the lengthwise tensile strength both in the dry condition is 1.5 to 5.0. The tensile strength of the present invention is, a tensile strength determined by tensile strength testing method which is regulated by Japanese Industrial Standard P8116.
In general, the strength of sanitary paper is reduced when the paper is merely softened. Accordingly, it is preferable that the tensile strength be kept within the range of the present invention.
Further, according to the sanitary paper of the present invention, it is preferable that the NBKP content of pulp material is 30.0 to 80.0%. The present invention is especially suitable for above-mentioned objects when the present invention is sanitary paper specified above.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram showing a function of sanitary paper containing a solution.
FIG. 2 is a schematic diagram showing a testing method of bending hardness.
FIG. 3 is a schematic diagram showing a relation between curvature and bending moment.
FIG. 4 is a schematic diagram showing a relation of compression characteristic
FIG. 5 is a schematic diagram showing a testing method of surface characteristic.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The sanitary paper of the present invention comprises at least one of the basic structures mentioned below, although it is a matter of course that sanitary paper which fulfills the both conditions is more preferred.
The First Basic Sturucture
A paper base is contained a solution, and the oil absorbance of the sanitary paper is made to be 7.0 mm or less. The oil absorbance of the sanitary paper is measured, under the standard condition which is regulated by Japanese Industrial Standard P8111, according to the Klemm water absorbance test which is regulated by Japanese Industrial Standard P8141, where water is replaced with cooking oil on the market (made by THE NISSHIN OIL MILLS, LTD.). The measuring time length is 60 seconds and the flow of the paper is longitudinal (which is the way of manufacturing line flow). That is, a specimen of the sanitary paper is put in a longitudinal position, the lower edge of the paper is dunked into the cooking oil, the height of the rising the cooking oil is measured 60 seconds later and is regarded as the mean value often points of tie specimen.
The Second Basic Structure
The humidity of sanitary paper is controlled under the condition that is regulated by Japanese Industrial Standard P8111 and a moisture content of sanitary paper is 9.50 to 15.00%, determined in accordance with Japanese Industrial Standard P8127.
A Typical Structure
In the embodiments of this present invention, the following typical structure can be adopted on above-mentioned basic structure.
As a paper base, publicly available product can be used without question. A product having the NBKP content of pulp material is 30.0 to 80.0%. (in accordance with Japanese Industrial Standard P8120), especially 50.0 to 70.0% is suitable as a paper base of the present invention.
The basis weight (determined in accordance with Japanese Industrial Standard P8124) of sanitary paper is preferably 10.0 to 35.0 g/m 2 . The paper thickness of sanitary paper is preferably 130 to 200 .mu.m by two-ply tissues. The crape rate of sanitary paper is preferably 15.0 to 26.0.
When a solution is contained in a paper base, usually an oil absorbance can be 1.0 to 7.0 mm, and especially 4.0 to 6.5 is preferable. Such sanitary paper can be manufactured by applying the solution onto the paper base (other solution applying methods can also be adopted) while adjusting the amount of the solution content per unit volume of a paper base within 46.0 to 160.0 mg/cm 3 , especially within 48.0 to 60.0 mg/cm 3 .
The solution content of the sanitary paper was determined as below. By using a Soxhlet extractor, approximately 10 g of specimen were immersed in 120 to 140 ml of ethanol-benzene solvent (the solvent ratio of ethanol to benzene is 1:1) and were heated and extracted for four hours while keeping the extract liquid lightly boil over a warm bath, and then left to stand in a drier which was held at constant temperature 150±2° C. for 90 minutes and the weight of the extract was measured and the measurement was divided by absolute dry weight of specimen to determine the rate as a percentage %. The solution content per unit volume of paper (=an amount of the applied solution) was calculated by the next formula.
An amount of the applied solution=basis weight (per ply)×2 (plies)×solution content (%)×1000 ÷(volume per unit area)
However, a volume per unit area is, paper thickness (μm)÷10000×100×100.
Accordingly, by making the oil absorbance low enough, it will be difficult to remove the sebum of corneal surface by sanitary paper, and therefore the moisture inside the corneum will be preserved by sebum. As a result, the skin will not become rough or reddish easily. Further, when an amount of the solution content becomes more than 160.0 mg/cm 3 , the sanitary paper will show sticky feeling and will give the users an unpleasant feeling.
For a solution, publicly available product can be used without question. Especially, when a solution is a slightly acid solution of pH 5.0 to 6.0, more suitably of pH 5.3 to 5.7, the skin will not turn into alkaline even when the sanitary paper touches the skin. Accordingly, the skin Will be prevented effectively from the roughness which will be caused by an affection of the pH of the solution. The pH adjustment means are to add a pH adjustment solvent, that are add or basic, into the solution. When the solution is strongly acidic, a sodium hydroxide solution or a potassium hydroxide solution can be added and when the solution is a neutral or an alkaline, a citric acid or a malic acid or a lactic acid can be added.
Ingredients of the solution of the present invention can be chosen suitably from moisturizer, softener and antioxidant. Choosing all of them are specially preferred. For the moisturizer, a polyhydric alcohol, sorbitol and a solvent of glycol series are good for use. By using these moisturizers, the moisture of the sanitary paper will become rich enough. Besides, collagen can be used with these moisturizers, and by this, moisture will be provided onto the skin effectively also.
A softener can be chosen suitably from anionic surfactants, nonionic surfactants, cationic surfactants and zwitterionic surfactants. Especially, an anionic surfactant is suitable. When an anionic surfactant is chosen, the firmness (a hardness of bending) of the paper base will be decreased to the range mentioned above, resulting in a further improvement in the moistness attributable to the moisturizers and the softness attributable to the softeners. As an anionic surfactant, a carboxylate-based, sulfanate-based, sulfate ester salt-based, phosphate ester salt-based surfactant may be employed. An alkyl phosphate ester salt is especially preferred.
As a nonionic surfactant, a polyhydric alcohol monofatty acid ester such as a sorbitan fatty acid ester, diethylene glycol monostearate, diethylene glycol monooleate, glyceryl monostearate, glyceryl monooleate, propylene glycol monostearate, and N-(3-oleyloxy-2-hydroxypropyl)diethanolamine, polyoxyethylene hydrogenated castor oil, polyoxyethylene sorbitol beeswax, polyoxyethylene sorbitan sesquistearate, polyoxy ethylene monooleate, polyoxyethylene monolaurate, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether may be employed.
As a cationic surfactant, a quaternary ammonium salt, amine salt or amine can be used. As a zwitterionic surfactant, a secondary or tertiary amine aliphatic derivative or a heterocyclic secondary or tertiary amine aliphatic derivative carrying a carboxy, sulfonate and sulfate can be employed.
As an antioxidant, vitamin C and vitamin E can be used. When the vitamins are used, the effect of preserving moisture of the sanitary paper and the effect of preventing skin from turning into acid will be exhibited. Especially, when vitamin C and vitamin E both arc used together, vitamin C works as a promoter of vitamin E, therefore the antioxidant action of vitamin E can be maintained longer. Vitamin E is an ingredient which has a strong reducing force and possesses an antioxidant action such as elimination of activated oxygen-free radical and a prevention of the generation of lipid peroxide. Accordingly, vitamin E will work as a stabilizer of the solution and also when the sanitary paper is given to the skin of the user, it will exhibit an oxidization prevention effect and a circulation of the blood promotion effect onto the sebum of the skin. Vitamin E also possesses a moisture preservation function. On the other hand, vitamin C has an antioxidant action on sebum, the same as vitamin E. As vitamin C acts to reduce vitamin E, when vitamin C and vitamin E both are used together, vitamin C works as a promoter of vitamin E, whereby reducing the vitamin E once oxidized by the activated oxygen, resulting in the preservation of the strong antioxidant action on seburn of vitamin E.
In addition, a collagen can be added if necessary to exert a moisturizing effect on the skin as well as a moisturizing effect also on the sanitary paper. Although an amount of collagen to be added can be determined suitably, it is preferable that the amount of collagen be as same level as antioxidant on the point of cost-effectiveness.
When using the above-mentioned solution, it is preferable to adopt the following combination.
Active ingredient from 60 to 100% by weight (especially from 80 to 100% by weight)
Moisturizer from 95 to 100% by weight (especially from 95.5 to 97.0% by weight)
Softener from 0 to 5% by weight (especially from 3.0 to 4.5% by weight)
Antioxidant from 0.000001 to 0.001% by weight Water from 0 to 40% by weight
The moisture content of the sanitary paper of the present invention of 9.50 to 12.00% is especially preferred
It is preferable forte sanitary paper of the present invention that the bending hardness B of the sanitary paper is 0.0040 to 0.0060 g/cm 2 /cm. The bending hardness B of the present invention is determined as below. That is, by using an “Automatic Pure Bending Tester KESFB2-AUTO-A”, manufactured by KATO TECH CO., LTD., and as shown in FIG. 2 , a 20 cm wide paper specimen, having a 1 cm chuck interval, is bended by pure bending way, a bending way which always maintain one side of the paper an arc. First, bend it toward the front side till the maximum curvature reaches 2.5 cm −1 and put it back to the origin, and next, bend it toward the backside till the maximum curvature reaches−2.5 cm −1 and put it back to the origin. At this moment, relation between curvature and bending moment is evaluated. This relation is obtained as a value on the Hysteresis curve line as shown in FIG. 3 . And the mean value of lengthwise and crosswise of bending hardness B (the mean B), in which the bending hardness B is indicated as an average inclination between curvature 0.5 and 1.5 cm −1 , is the bending hardness B of the present invention. As the mean value of bending hardness B (the mean B) become higher, the sanitary paper will become firmer and more difficult to bend.
Further, it is preferable for the sanitary paper of the present invention that the softness per basis weight of the sanitary paper is 5.4 to 6.4 cm 2 /100. The “softness” of the present invention is, a value of resistance (a mean value of lengthwise and crosswise) when a 10 cm wide paper is pushed into a 5.0 mm wide crevice by a terminal and it can be measured by the so-called “Handle O Metet”.
Further, it is preferable for the sanitary paper of the present invention that the compression characteristic TM, T 0 and (T 0 -TM) is within the next range.
A thickness TM under a 50 g/cm 2 load: 0.160 mm or more for 1-ply tissues
A thickness T 0 under a 0.5 g/cm 2 load: 0.350 mm or less for 1-ply tissues
T 0 -TM: 0.200 mm or less for 1-ply tissues TM/(T 0 -TM): from 0.800 to 1.500
This compression characteristic test is done by using a “Handy Compression Tester KES G5”, manufactured by KATO TECH CO., LTD. A paper specimen was compressed till the maximum compression load 50 g/cm 2 between iron plates, which plate has a circle plane with a 2 cm 2 compression area. And the compression characteristic of the paper specimen returning to former state was evaluated. The compression characteristic indicated at this moment, may be described as a relation shown in FIG. 4 .
Further, it is preferable for sanitary paper of the present invention whose surface charactetistics MMD and MIU are within the following range.
MMD (the mean deviation of friction coefficient): from 0.0180 to 0.0250 MIU (the mean friction coefficient): from 0.4000 to 0.5000
This surface characteristic test is done by using a “Friction Sensitivity Tester KES-SE”, manufactured by KATO TECH CO., LTD. This tester, as shown in FIG. 5 , measures the friction coefficient as below. While contacting a paper specimen with a friction probe, made by a piano wire which has a cross section with a diameter of 0.5 mm and having a 5 mm-long contacting surface, by touching a log contact pressure, a 20 g/cm tension is applied to the paper specimen in the moving direction and, at the same time, the paper specimen moves 2 cm at a speed of 0.1 cm/sec and the friction coefficient is measured. Furthermore, the mean deviation of friction coefficient MMD is a change of the surface thickness when the friction probe moved, that is, a value of friction coefficient divided by friction distance (the moving distance=2 cm).
On the other hand the sanitary paper of the present invention is preferable for a product which is used for rubbing the skin such as facial tissue or toilet paper, but also it can be used for other purposes too. When such a purpose has been considered, it is preferable for the sanitary paper of the present invention that the basis weight per 1-ply tissues is 10 to 35 g/m 2 and the sanitary paper consists of 1 to 3-ply tissues. Further, it is preferable for the sanitary paper of the present invention that the lengthwise tensile strength in a dry condition is 60 to 160 N/m, especially 80 to 140 N/m, crosswise tensile strength in a dry condition is 20 to 60 N/m, especially 25 to 40 N/m, and the ratio of the lengthwise tensile strength in a dry condition to the crosswise tensile strength in dry condition is 1.5:1.0 to 5.0:1.0, especially 2.0:1.0 to 3.5:1.0. Still more, it is preferable for the sanitary paper of the present invention that the tensile strength in wet condition is, the longitudinal: 30.0 to 60.0 N/m, and the widthwise: 10.0 to 30.0 N/m −1 When the sanitary paper simply softens, the strength of the paper itself will drop too but by maintaining the tensile strength within such a range, the sanitary paper will become suitable for rubbing skin such as a facial tissue.
EXAMPLE
As shown in Tables 1 and 2, various physical properties of various facial tissues were measured, calculated and evaluated organoleptically (an example of the present invention, traditional product, and commercial products A, B. C and D). The method of the measurement, calculation and organoleptic evaluation are written below. The measurements of the physical properties were carried out under the conditions that are regulated by Japanese Industrial Standard P8111. Further, the consequence of measurements and such are shown in Table 3.
(1) Basis weight (1-plytissues): measured in accordance with Japanese Industrial Standard P8124. (2) Paper thickness (2-plytissues): The paper thickness is measured by using a dial thickness gauge “PEACOCK G type” manufactured by OZAKI MFG. CO., LTD. under the conditions that are regulated by Japanese Industrial Standard P8111. Typically, first check that there is no rubbish or dust between the plunger and the measuring pedestal. Then, put down the plunger on the measuring pedestal, set the dial of the dial thickness gauge at 0, raise the plunger and put the specimen (a facial tissue) onto the pedestal of the tester. And then, put down the plunger slowly and read the gauge. At this moment merely the plunger is put on the specimen. The measurement is done on one sheet and the mean value of 10 measurements is the paper thickness. (3) Density: calculated by the next formula.
Basis weight×2/(paper thickness/10000×100×100.
(4) Solution content: as mentioned above. (5) Solution content per volume unit of the paper: as mentioned above. (6) Oil absorbance: as mentioned above. (7) Compound ratio of NBKP: measured in accordance with Japanese Industrial Standard P8120. (8) Crape rate: calculated by the next formula.
((A circumferential speed of the drier while manufacturing paper)−(Circumferential speed of a reel))/(Circumferential speed of the drier while manufacturing paper)×100
(9) Tensile strength: measured in accordance with Japanese Industrial Standard P8113. (10) Ratio of a lengthwise tensile strength to a crosswise tensile strength: calculated by next formula. Lengthwise tensile strength/Crosswise tensile strength (11) Stretch rate: An elongation at break in a lengthwise tensile strength test. (12) Moisture content: measured in accordance with Japanese Industrial Standard P8127. (13) Softness: A softness is measured by “Handle O Meter”. (14) Bending hardness B: measured by using a pure bending tester (“Automatic Pure Bending Tester KESFB2-AUTO-A”, manufactured by KATO TECH CO., LTD.). Further, as a bending hardness B become higher, the characteristic of facial tissue will become firmer and more difficult to bend. (15) T 0 and Tm: measured by using a compression tester (“Handy Compression Tester KES-G5”, manufactured by KATO TECH CO., LTD.). Further, as T 0 -TM become higher, it shows that the feel of the paper become soft. (16) Mean friction coefficient MIU and a friction distance MMD: measured by using a surface characteristic tester (“Friction Sensitivity Tester KES-SE”, manufactured by KATO TECH CO. LTD.). (17) Organoleptic evaluation: conducted by blowing one's nose for the designated number of times and scoring how hard to feel pain according to a five-grade system. The values are the mean value of 20 people of men and women.
TABLE 1
Example of
the present
Usual
Product A on
Product B on
Product C on
Product D on
invention
product
the market
the market
the market
the market
Basis weight (g/m 2 )
17.5
17.1
15.1
17.8
15.1
18.3
Paper Thickness 2-ply tissues (μm)
160
134
142
163
139
162
Volume per area unit of the paper
160
134
142
163
139
162
(cm 3 /m 2 )
Solution content (wt %)
23.4
17.6
19.3
19.8
3.7
18.7
Solution content per volume unit of the
51.2
45.0
41.0
43.2
8.0
42.2
paper (mg/cm 3 )
Oil absorbance (mm)
5.5
9.0
8.3
8.0
7.6
7.2
pH of solution
5.6
6.5
—
—
—
—
NBKP content (wt %)
60.0
60.0
—
—
—
—
Crape rate (%)
22.0
22.0
—
—
—
—
Lengthwise tensile strength in dry
83.2
184.0
133.6
86.0
141.2
86.4
condition (N/m)
Crosswise tensile strength in dry
22.0
36.0
45.2
31.6
29.2
28.8
condition (N/m)
Ratio of lengthwise tensile strength to
3.78
5.11
2.96
2.72
4.84
3.00
crosswise tensile strength in dry
condition
Longitudinal stretch rate (%)
11.7
10.9
13.1
11.8
10.5
11.7
Lengthwise tensile strength in wet
40.4
79.6
46.8
31.6
36.0
37.6
condition (N/m)
Crosswise tensile strength in wet
12.0
18.4
19.6
14.0
9.2
15.6
condition (N/m)
Moisture content (%)
10.02
9.14
8.16
9.11
8.16
9.21
Softness (g)
1.10
1.16
1.32
1.19
1.26
1.18
Softness/unit weight × 100 (m 2 /100)
6.286
6.784
8.742
6.685
8.344
6.488
TABLE 2
Example of
the present
Usual
Product A on
Product B on
Product C on
Product D on
invention
product
the market
the market
the market
the market
Bending hardness B
0.0050
0.0068
0.0095
0.0075
0.0094
0.0062
(gcm2/cm)
T0 (mm)
0.307
0.359
0.385
0.422
0.364
0.423
Tm (mm)
0.162
0.133
0.152
0.149
0.156
0.148
T0 − Tm (mm)
0.145
0.226
0.233
0.273
0.208
0.275
Tm/(T0 − Tm)
1.117
0.588
0.652
0.546
0.750
0.538
MIU
0.4373
0.4990
0.3443
0.3879
0.2812
0.4009
MMD
0.0239
0.0232
0.0248
0.0199
0.0222
0.0209
TABLE 3
Example of
the present
Usual
Product A on
Product B on
Product C on
Product D on
Organoleptic evaluation
invention
product
the market
the market
the market
the market
The hardness of nose
4.63
3.00
3.13
3.23
3.13
3.45
to get painful
The feel of moistness
4.25
3.00
2.50
3.00
2.50
3.50
The feel of softness
4.38
3.00
2.50
3.00
2.75
3.38
The feel of thickness
4.25
3.00
3.13
3.63
3.13
3.25
Overall evaluation
4.38
3.13
2.25
3.00
2.38
3.38
The example according to the present invention has a lower oil absorbance compared to others, so that it will not absorb oil easily, and also has a high solution content and a high moisture content as shown in Tables 1 to 3, the example acquired remarkably superior result in the Organoleptic evaluation. According to the present invention, the example is a sanitary paper which is excellent in touch onto skin such as moistness and softness and which does not sting and makes the skin red even if the sanitary paper touches the skin frequently.
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It is intended to provide sanitary paper which is excellent in texture such as moistness and softness and scarcely causes skin irritation or blushing even if it is brought into contact with the skin frequently. Namely, sanitary paper having an oil absorbance specified in JIS P8141 of 7 mm or less and a moisture content of from 9.50 to 15.00% (measured in accordance with JIS P8127 after conditioning in accordance with JIS P8111); carrying a solution, which contains a moistening agent, a softener, an antioxidant and so on, coated in a dose of 46.0 to 160.0 mg/cm3 of the paper base; and having a bending hardness B measured with the use of a pure bending machine of from 0.0040 to 0.0060 g·cm 2 /cm.
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FIELD OF THE INVENTION
[0001] The present invention relates to hand tools capable of being used with multiple bits. More specifically, the present invention relates to a screwdriver removably coupled with a storage device which holds multiple driver bits, allows easy access to the bits and provides a method of using the screwdriver for projects requiring multiple bits.
BACKGROUND OF THE INVENTION
[0002] Carpenters, electricians, mechanics, other skilled workers and even lay people rely on a wide variety of tools to complete their work. Various tools and bits are frequently needed by these workers including screwdrivers, slotted screws, Phillips-Head screws and connections, pozidriv bits, tori bits, alien wrenches and screws, hex key bits, Robertson bits, tri-wing bits, torq-sets, spanner bits, drill bits, sockets of various shapes and sizes and the like.
[0003] Furthermore, the above-listed tools are needed in various sizes. For example, an automobile mechanic might need to loosen a large slotted screw. To achieve enough torque to loosen a large slotted screw, a large slot screwdriver is needed. However, this screwdriver would be useless to the same mechanic who wanted to loosen the tiny screws of a car audio system.
[0004] Tools requiring bits typically utilize a “loose bit” solution. According to this solution, a hand tool or similar tool is separate from the bit holder containing bits. Workers face several problems with this configuration due to the many components and the hassle corresponding to the methods of accessing them.
[0005] According to the “loose bit” solution, the user must set down the hand tool, pick up the bit holder with one hand, use the other hand to choose and access a desired bit from the bit holder, set down the bit holder and finally couple the selected bit to the hand tool. This traditional method of changing bits requires many parts, many steps and many motions.
[0006] Alternatively, a user of a “loose bit” tool system might attempt to hold the numerous tools simultaneously, for example, the driver, the bit holder, the current bit, the replacement bit, etc, as well as holding work pieces. This practice often times results in a load that is too heavy or awkward for the user to work dexterously and in a constant potential to drop one of these components. Finally, it is particularly difficult to perform the tasks required according to the “loose bit” solution while on a ladder or in other positions requiring great precision or balance.
[0007] Next, when utilizing a “loose bit” method, a user cannot conveniently test a bit for the proper fit with a screw or other work piece. Rather, the user must guess what size is appropriate, and then access bit after bit from a “loose bit” bit holder until the correct bit is found without a convenient way to “test fit” a bit.
[0008] Also, organizing all these tools is time consuming and takes up space. Furthermore, many tools come in both American and metric sizes. For example a ¼ inch allen wrench is very close in size to a 6 mm alien wrench. However, the two cannot be used interchangeably, requiring two sets of nearly identical wrenches. Next, tools are expensive and a carpenter can spend a lot of money buying the multiple screwdrivers, allen wrenches and other tools which are needed to do even a single job. Furthermore, traditional tool boxes and shelving can store many screwdrivers, wrenches and bits, but they do not provide an easy way to locate particular bits within the box.
SUMMARY OF THE INVENTION
[0009] A hand tool with a storage device is disclosed. In some embodiments of the invention, a ratchet is included on the hand tool. The ratchet alternatively allows either clockwise or counterclockwise rotation. In some embodiments of the present invention, a magnet is included on the hand tool's bit interface to provide strength to the interface. The hand tool is removably coupled to a bit storage device. The bit storage device holds bit inserts, which hold individual bits. In some aspects of the present invention, the hand tool itself accommodates bit inserts. In some embodiments of the present invention, the bit storage device holds multiple bit inserts. In some embodiments of the present invention, the bit storage device or the bit inserts are labeled according to the contents therein. The bit inserts are configured to bend and distort to more easily access the stored bits contained therein. The hand tool and bit insert are configured such that a user is able to access the bit insert, remove bits from the hand tool with the bit insert, access and couple a new bit from the bit insert to the hand tool, all without setting any pieces aside, allowing for fewer steps and motions and reducing the potential for dropping or losing bits. In some embodiments of the present invention, a locking system is utilized to keep the bit inserts in place. A finger grip allows a user easier access to the bit inserts in the storage device and allows a user to squeeze the grip
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The novel features of the invention are set forth in the appended claims. However, for the purpose of explanation, several embodiments of the invention are set forth in the following figures.
[0011] FIG. 1A illustrates a perspective view of the hand tool and bit storage device according to one embodiment of the present invention.
[0012] FIG. 1B illustrates a perspective view of the hand tool and bit storage device with hand tool interacting with a removed bit insert.
[0013] FIG. 2A illustrates a perspective view of the hand tool and bit storage device according to another embodiment of the present invention.
[0014] FIG. 2B illustrates a close up view of the bit insert and bit interface according to some embodiments of the present invention.
[0015] FIG. 3 illustrates a perspective view of the hand tool and bit storage device according to yet another embodiment of the present invention.
[0016] FIG. 4 illustrates a perspective view of the locking system used with the hand tool and bit storage device according to some embodiments of the present invention.
DETAILED DESCRIPTION
[0017] For the purpose of this disclosure, the word bit shall refer to any tool, device, accessory or the like which is normally associated with hand tools, wrenches, drills or the like, including, but not limited to, slotted screws, Phillips-Head screws and connections, pozidriv bits, torx bits, alien wrenches and screws, hex key bits, Robertson bits, tri-wing bits, torq-sets, spanner bits, drill bits, sockets of various shapes and sizes or the like.
[0018] FIG. 1A provides a perspective view of a hand tool 101 and a bit storage device 102 according to some embodiments of the present invention. The hand tool 101 has a body portion 103 , a stem portion 104 and a bit interface 105 .
[0019] The body portion 103 is designed to comfortably fit in a user's hand and also to provide torque on the bit interface in an amount needed for common applications in carpentry, electronics, mechanics and the like. The stern portion 104 is coupled to the body portion 103 and to the bit interface 105 . In some embodiments of the present invention, the stem portion 104 is thinner than the body portion 103 to allow the stem portion 104 and the bit interface 105 to fit into smaller spaces than the body portion 103 in order to access work pieces, while still allowing the user to exert adequate torque on the work pieces from a distance.
[0020] In some embodiments of the present invention, the hand tool also includes a ratchet device (not shown) and a ratchet housing 110 . The ratchet housing 110 rotates around the axis of the stem portion 104 by some arc to toggle between clockwise and counterclockwise driving. When the ratchet housing 110 is positioned at one end of the arc, the ratchet allows the stem portion 104 and the bit interface 105 to rotate in the clockwise direction, thus driving standard screws or tightening standard bolts. In such a position, a counter-clockwise rotation does not turn the stem portion 104 . When the ratchet housing 110 is positioned at the other end of the arc, the ratchet allows the stem portion 104 and the bit interface 105 to rotate in the counter-clockwise direction, thus retracting standard screws or loosening standard bolts. In such a position, a clockwise rotation does not turn the stem portion 104 .
[0021] The bit storage device 102 includes a fixture 108 . The stem portion 104 of the hand tool 101 couples with a bit storage device with a fixture 108 . As shown, the fixture 108 is a pressure fixture comprised of two flanges 112 , 113 extending from the base 109 of the fixture 108 . However, it will be appreciated by those skilled in the art that other means for coupling the hand tool to the bit storage devices are contemplated including, but not limited to straps, slots, hook and loop fasteners, snaps, and tongue and groove configurations. In other embodiments, the hand tool 101 and bit storage device 102 are not coupled, but are each designed to fit into an especially designed carrying case, box or pouch.
[0022] The bit storage device 102 is a substantially hollow structure with two removable storage tools 106 , 107 inserted within the structure. The removable storage tools hold bits (not shown) which couple with the bit interface 105 . The hand tool with accessory storage according to the embodiment shown in FIG. 1A allows the user to access a hand tool 101 and easily access and change bits (not shown) as dictated by the project being worked on.
[0023] FIG. 1B shows the hand tool 101 and bit storage device 102 with the removable bit storage tool 106 removed. The removable bit storage tool 106 contains a number of bits 111 . As shown, the bits 111 each have hexagonal interfaces for interfacing with the bit interface 105 . It will be apparent to those skilled in the art that other shapes for interfacing between the bits and bit interface is contemplated. In some embodiments of the present invention, a 6.6 mm hex bit interface is used. In other embodiments, a 0.25 inch hex bit interface is used. Although specific sizes and shapes for the bit interface have been disclosed, it will be readily apparent to those skilled in the art that any other sizes and shapes for the bit interface are contemplated.
[0024] FIG. 1B also shows the storage tool frame cap 114 on the bit storage tool 106 . The storage tool frame cap 114 is slightly larger than the circumference of the bit storage tool 106 so that a user can easily grip the frame cap 114 . The storage tool frame cap 114 also has protrusions 119 situated on its surface to provide friction to a user accessing the storage tool frame cap 114 . Furthermore, the storage tool frame cap 114 is coupled to a cap node 117 . The cap node 117 aides in retaining the bits 111 within the bit storage tool 106 , as will be explained in more detail when referring to FIG. 4 .
[0025] FIG. 2A provides a perspective view of another embodiment of the present invention with a hand tool 201 which accommodates a removable bit storage tool 208 and a bit storage device 202 . In this embodiment, the body 203 of the hand tool 201 is substantially hollow and accommodates a removable bit storage tool 208 . As shown, the bit storage device 202 holds the removable bit storage tools 206 and 207 . However, the removable bit storage tools 206 , 207 and 208 are interchangeable and are able to be held within either the storage device 202 and the body 203 . FIG. 2B shows details of the removable bit storage tool 208 . The basic structure of the bit storage tool 208 is a semi-rigid polymer, which forms the frame 215 of the storage tool 208 . The frame 215 is connected in spots by nodes 216 . In some embodiments, the nodes 216 are more flexible than the frame 215 . In the preferred embodiment, the nodes 216 are comprised of a resilient polymer. The frame 215 is connected by the nodes 216 to form a number of holes to accommodate the bits 211 . The bits 211 are inserted into the holes and are held in place through friction exerted on the bits by the frame 215 and the nodes 216 . It is preferred that a certain threshold of force be applied to the bits 211 to remove them from the bit storage tool 206 . This threshold is preferably greater than the bits' 211 force due to gravity and also small forces created by normal jostling of the bit storage tool 208 .
[0026] To remove the bits 211 from the bit storage tool 208 , a user is able to manually push the bit from the side of the frame 215 . Alternatively, a user is able to use the hand tool 201 itself as a bit insertion and extraction means. Using the hand tool 201 as a bit insertion and extraction means simply requires a user to hold the bit storage tool 208 with one hand and insert the bit interface 205 coupled with a bit into an empty portion of the frame 215 with the other. The user is then able to pull the hand tool out of the frame 215 while leaving the bit coupled to the frame 215 . Additionally, to couple the hand tool 201 with a bit, a user is able to access a bit 211 from the frame 215 by coupling the bit interface 205 with a bit 211 and pulling the bit 211 from the frame 215 .
[0027] These features give the user the ability to install and remove bits 211 directly from the bit insert frame 215 without ever putting down the hand tool 201 and without having to reach for a bit holder. This features allows the interchanging of bits in fewer steps, with fewer motions and with less of a risk of losing or dropping bits. As such, this configuration is superior to “loose bit” systems which require additional steps and present additional challenges, as described above.
[0028] In some embodiments, a user is able to squeeze one or more nodes 216 adjacent to a particular bit to aid in removing the bit from the frame 215 . Squeezing the nodes 216 causes the shape of the frame 215 and the shape of the holes to distort. Such distortion allows easier access to the bits 211 .
[0029] Another flexible polymer node comprises a cap node 217 coupled to a finger grip 218 at the top of the bit storage tool 206 . The surface of the finger grip 218 contains a number of protrusions 219 to ensure friction between the user's finger and the finger grip 218 . Squeezing the cap node 217 distorts the shape of the top of the bit storage tool 208 , allowing easier removal of the bit storage tool 208 from the bit storage device 202 . The bit storage tools 206 and 207 ( FIG. 2A ) is also removable from the bit storage device 202 , and bits are likewise removable from bit storage tools 206 and 207 in a similar manner.
[0030] FIG. 2B also illustrates how the hand tool 201 with the bit interface 205 interfaces with the bit storage tool 208 and the bits 211 . The bit interface 205 is designed to fit tightly over the bit 211 . In some embodiments of the present invention, the bit interface 205 contains a magnetic core. The magnetic core creates a stronger bond between the bit 211 and the bit interface 205 . The magnets chosen for the magnetic core may be selected from among: Ferrite Magnets, Neodymium Magnets, Samarium-cobalt Magnets, Ceramic Magnets and Alnico Magnets, among others. The user is able to push the bit 211 from the other side of the frame 215 to remove the bit 211 or can put pressure on a node 216 adjacent to the bit, as described above.
[0031] Furthermore, both ends of the bits 211 are able to be seen accessed from the sides of the bit storage tool 208 . As such, a user can “test fit” the bit 211 with a particular screw or other work piece without first removing the bit 211 from the frame 215 . This feature further saves the user the time required to fit a screw or other work piece of an unidentifiable size with the correct bit.
[0032] In some embodiments, each bit storage tool houses a different type of bit such as: slotted bits, phillips bits, pozidriv bits, tori bits, hex key bits, robertson bits, tri-wing bits, torq-sets, spanner bits or star bits. According to this embodiment, three different types of bits are stored and immediately accessible to the user of one tool.
[0033] FIG. 3 provides a perspective view of yet another embodiment of the present invention. Here, a hand tool 301 with a removable bit storage tool 308 couples with a bit storage device 302 . The bit storage device 302 holds four bit storage tools 306 , 307 , 309 , 310 . As such, the embodiment shown is able to store five bit storage tools allowing a user to have a very wide variety of tools immediately accessible. In some embodiments, pictures, words, symbols, colors or similar identifying markings are marked on the body of the bit storage device and depict the contents of each of the bit storage tools. FIG. 3 depicts symbols on the body of the bit storage device which depicts the contents therein. Symbol 399 shows that bit storage tool 306 contains slotted screw bits. Symbol 398 shows that bit storage tool 307 contains Phillip's head screw bits. Symbol 397 shows that bit storage tool 309 contains alien bits. Symbol 396 shows that bit storage tool 310 contains star bits.
[0034] In other embodiments of the present invention, markings on the body of the bit storage device or on the body portion of the hand tool indicate whether the bits contained therein are either American sized or metric.
[0035] FIG. 4 illustrates another embodiment of the present invention in which the removable bit storage tools lock into the bit storage device or the hand tool. In FIG. 4 , a close up of a removable bit storage tool 407 is shown entering a bit storage device 402 . The bit storage tool 407 has a frame portion 412 and a frame cap 401 with finger grip protrusions 403 . The frame cap 401 which protrudes further out than the rest of the frame portion 412 . Adjacent to frame cap 401 are cap nodes 411 .
[0036] The bit storage device 402 has an opening to hold the bit storage tool 407 . The opening in the bit storage device 402 contains spaces 405 to accommodate the nodes 411 of the frame cap 401 . Further, the opening features two semi-flexible and resilient clips 406 . When the bit storage tool 407 is inserted into the bit storage device, the bit storage tool 407 passes over the rounded ends of the clips 406 , causing the clips 406 to bend out. When positioned correctly, the clips 406 fit into the grooves 404 when the bit 407 is fully inserted, thereby locking the bit storage tool 407 into the bit storage device 402 .
[0037] In some embodiments, the cap nodes 411 help a user insert bits into the frame 415 and remove bits 412 from the frame 415 . According to these embodiments, the cap nodes 411 are composed of a more flexible material than the rest of the upper portion 401 . In the preferred embodiment, the cap nodes 411 are comprised of a resilient polymer. When pressure is applied to the cap nodes 411 , the shape of frame 415 and the shape of the nodes 413 distort, causing the holes to change shape. As pressure is applied or removed from the cap nodes 411 , the holes are either tightened or loosened. When the holes are tightened, a user is able to exert enough force on the bits 412 from the bit interface (not shown) to couple the bit 412 to the bit interface from one side of the frame without forcing the bit 412 to come out the other side of the frame 415 . A user is then able to release some pressure from the cap node 411 , causing the holes to loosen. When the holes are loose enough, the user is able to remove the bit 411 from the frame 415 by pulling the bit interface away from the hole. As such, the cap nodes allow a user to change bits without requiring them to set down the hand tool and use two hands as they do in a “loose bit” application.
[0038] The present invention, as disclosed, provides significant advantages over traditional tools and tool storage systems. First, unlike “loose bit” tools, the present invention allows a user to change bits without ever having to put their tool or work pieces aside. Furthermore, the present invention allows a user to change bits with fewer steps and motions and limits the potential for dropping or losing bits.
[0039] Furthermore, the present invention cuts down the cost of buying tools. Using the hand tool and bit storage tools and holders of the present invention eliminates the need to purchase individual hand tools with each particular fitting. For example, the present invention eliminates the need for multiple sized flat head hand tools and the need to buy both a flathead and a phillips head hand tool because the present invention is able to hold all of them. For instance, the bit storage tools are able to hold various sized slotted screws, Phillips-Head screws and connections, pozidriv bits, torx bits, allen wrenches and screws, hex key bits, Robertson bits, tri-wing bits, torq-sets, spanner bits, drill bits, sockets of various shapes and sizes or the like. Also, those skilled in the art will appreciate that the removable bit storage tools are able to hold a wide variety of other tools.
[0040] The present invention also serves to conserve space and simplify organizing. The need to organize multiple hand tools of various sizes and shapes, alien wrenches, sockets, and the like on a tool bench or in a tool box is eliminated. With the present invention, all the bits required are able to be stored easily and are easily organized in a user friendly fashion. For example, one removable bit storage tool might hold metric sized alien bits and another bit storage tool might hold American sized allen bits. Furthermore, a third removable bit storage tool might hold star bits. The storage tools are able to be labeled with printed words, color-coated, labeled with pictures of the bits they contain, or otherwise identified.
[0041] The present invention has been described in terms of specific embodiments incorporating details to facilitate the understanding of the principles of construction and operation of the invention. Such reference herein to specific embodiments and details thereof is not intended to limit the scope of the claims appended hereto. It will be apparent to those skilled in the art that modifications can be made in the embodiment chosen for illustration without departing from the spirit and scope of the invention. Specifically, it will be apparent to one of ordinary skill in the art that the device and method of the present invention could be implemented in several different ways and have several different appearances.
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A hand tool and bit storage device configured to allow easy storage and access to a wide variety of bits. The hand tool comprises a body portion, a stem portion and a bit interface. The hand tool couples with the storage device. The storage device holds one or more tool frames or bit inserts each comprising a plurality of bits. The bit inserts are deformable to allow easy access to the bits contained therein. In some embodiments, the bit inserts may be locked in the storage device.
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[0001] This application is a continuation-in-part application of Ser. No. 10/058,198 filed Jan. 25, 2002.
[0002] The present invention relates to the field of security identification systems, and relates in particular to systems and methods for verifying the identity of persons in high volume screening applications.
BACKGROUND OF THE INVENTION
[0003] Conventional systems for verifying the identity of persons typically involve either the use of highly skilled screening personnel at a large number of screening points, or involve the use of biometric analysis systems. The use of a large number of highly skilled screening personnel that compare photographic identification documents or cards with the face of the person whose identification is being verified is difficult and expensive to achieve since each screener must be highly skilled in complex personal identification techniques. The use of poorly trained screening personnel presents a dangerous false sense of security. Moreover, even with highly skilled screeners, inconsistencies between procedures used by different screeners may present further difficulties.
[0004] The use of biometric analyses standardizes and automates much of the process, but applications using biometric analyses suffer from shortcomings as well. For example, many biometric analysis systems require some human interpretation of the data to be certain in a high percentage of cases, and this interpretation may vary. Moreover, the process of obtaining reliable and consistent biometric information from a large number of persons to be identified remains difficult due to biometric data capturing concerns, particularly with non-contact biometric data capturing. Certain conventional non-contact biometric data capturing systems use video cameras to capture the faces of people in a subject area, or employ non-contact sensors to capture characteristics of parts of a person's body. Such systems, however, remain inconsistent and insufficiently reliable, at least in part due to variations in how the subject is presented to the video camera or sensor. For facial recognition, poor lighting and poor pose angles present significant difficulties. Difficulties are also presented by having a moving subject with a fixed camera view area, particularly if the subject's face occupies a small portion of a large and highly varying view area. Other non-contact biometric techniques include iris scanning, which requires that each subject walk up to a capture device, align themselves correctly and have their iris scanned and verified. Contact based biometric systems, such as finger print readers, are generally considered to be less safe from a health standpoint due to having a large number of persons touch the same device over a long period of time.
[0005] For example, U.S. Pat. No. 6,119,096 discloses a system and method for automated aircraft boarding that employs iris recognition. The system, however, requires that each passenger be initially enrolled and scanned into the system. U.S. Pat. No. 6,018,739 discloses a distributed biometric personal identification system that uses fingerprint and photographic data to identify individuals. The system is disclosed to capture biometric data at workstations and to send it to a centralized server via a wide area telecommunications network for automated processing. Similarly, U.S. Pat. No. 6,317,544 discloses a distributed mobile biometric identification system with a centralized server and mobile workstations that uses fingerprint and photographic data to identify individuals. The system is disclosed to capture biometric data at workstations and to send it to a centralized server via a wireless network for automated processing. Each of these systems, however, may produce false positive identifications (which may overwhelm a review system) or miss certain identifications due to uncertainties in biometric data capture and/or analysis as discussed above.
[0006] There is a need, therefore, for an efficient and economical system and method that provides improved personal identity verification for a large number of persons in a high volume environment.
SUMMARY OF THE INVENTION
[0007] The invention provides a security identification system and method for providing information regarding subjects to be identified. In accordance with an embodiment, the system includes a primary biometric data input unit for receiving primary biometric data regarding a subject, a primary biometric analysis unit, a secondary biometric data input unit, a secondary biometric analysis unit, and a security clearance output unit. The primary biometric analysis unit is for analyzing the primary biometric data and comparing it against known biometric data in a database. The primary biometric analysis unit is also for providing primary match data that is indicative of whether a match exists with respect to the primary biometric data and whether the primary match data is above a minimum primary biometric data correlation threshold. The secondary biometric data input unit is for receiving secondary biometric data regarding the subject when the primary match data is below a minimum primary biometric data threshold. The secondary biometric analysis unit is for analyzing the secondary biometric data and comparing it against known biometric data in the database. The secondary biometric analysis unit is also for providing secondary match data that is indicative of whether a match exists with respect to the secondary biometric data and whether the secondary match data is above a minimum secondary biometric data correlation threshold. The security clearance output unit is coupled to the primary biometric data analysis unit and to the secondary biometric data analysis unit for providing an indication of whether the subject is cleared.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The following description may be further understood with reference to the accompanying drawing in which:
[0009] [0009]FIG. 1 shows an illustrative view of a screener using a system in accordance with an embodiment of the invention to screen a subject;
[0010] [0010]FIG. 2 shows an illustrative enlarged view of the screener of FIG. 1 wearing a data collection unit in accordance with the system shown in FIG. 1;
[0011] [0011]FIG. 3 shows an illustrative view of a screen display as seen by a screener in accordance with an embodiment of the invention;
[0012] [0012]FIG. 4 shows an illustrative flowchart of the operation of a system in accordance with an embodiment of the invention;
[0013] [0013]FIG. 5 shows an illustrative diagrammatic view of a system in accordance with an embodiment of the invention;
[0014] [0014]FIG. 6 shows an illustrative view of a packet of information that is communicated from a screener to a central facility in accordance with an embodiment of the invention;
[0015] [0015]FIG. 7 shows an illustrative view of a screen display as seen by an expert analyst in accordance with an embodiment of the invention;
[0016] FIGS. 8 A- 8 C show illustrative diagrammatic top, side and end views respectively of a contact biometric system in accordance with an embodiment of the invention; and
[0017] [0017]FIGS. 9A and 9B show illustrative flowcharts of the operation of a system in accordance with an embodiment of the invention.
[0018] The drawings are shown for illustrative purposes.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The present invention provides for systems and methods for optimally gathering biometric data and documentation data regarding individuals whose identity is to be verified in high volume screening applications. In an embodiment, the method involves the use of face to face human interaction to set up and execute scripted scenarios for operators (screeners) to follow, ensures that optimal quality data is captured in a highly consistent manner. The collection method is driven by the voice of the screener as part of the normal conversation with the person being screened. The screener is queued by an interactive teleprompter on a miniature screen display. In the case of ambiguous biometric results, the system invokes a live identification expert with access to auxiliary data to assist the field-based screener via live text, audio and video. The method provides significant improvement in biometric performance and improves screening efficiency. The system also provides interactive training of screening personnel in an embodiment based on their on-going performance.
[0020] As shown in FIG. 1, in accordance with an embodiment of the invention, a screener 8 may wear a specialized data collection and display device 10 that includes an earphone 12 , a camera 14 , a micro display 16 , and a microphone 18 . The camera 14 is a miniature high resolution color or grayscale camera. The micro display 16 is a miniature high resolution color/grayscale display that is viewable only by the screener, such as those sold by MicroOpical Corporation of Westwood, Mass. The display may project an image into space in front of the screener's face (again viewable only by the screener). As also shown in FIG. 2, the device 10 is connected via a cable 20 to a small computer 22 , which in turn communicates via an antenna 24 and a high speed wireless connection to a central analysis facility. The computer 22 may be worn by a screener on a waist belt out of view of the person being screened 26 . In further embodiments, the devices 10 may be made even smaller, with each communication device fitting on a single pair of eyeglasses so as to fully minimize the impact on the subject 26 and permit natural interaction between the screener 8 and subject 26 . Each device 10 is personalized at the time of use to a particular authorized screener. All communications with the central analysis facility are encrypted. The device application software includes two way voice, text (from the central facility) and two way video and still image capture/display, as well as local biometric data, compression, control and communication capabilities. The device 10 is completely driven by the voice of the screener for all real-time functions via keyword spotting that is tied to the main screening script as discussed in more detail below. The miniature display 16 may provide a significant amount of information in the form of a screen display 30 as shown in FIG. 3, including a photograph 32 of the subject 26 , a photograph of the subject's identification card (ID) 34 , a photograph of the subject's airline ticket 36 , a streaming video image 38 , and an image of an eye 39 for, e.g., iris scanning or retinal imaging. In certain embodiments, the camera 14 may have sufficient resolution to locate the one or both eyes in the image of the subject's face, and increase the scale of the eye to fill the viewing image to create the image 39 for processing. The display may also provide a results field 40 and a system status field 42 , and may further include text accompanying any of the various photographs or images as shown, as well as text generated from remote locations.
[0021] All devices 10 are connected in real time to one or more analysis facilities via standard high-speed commercial telecommunications providers. The analysis facility includes strong authentication and firewalls for incoming and outgoing communications. It contains a very high speed local area network (LAN)/storage area network (SAN) system, connecting database and analysis servers to devices 10 and to human analysts and quality control personnel. The analysis servers include generalized correlation engines, biometric correlation engines, as well as other automated support for screener based devices, in addition to local analysts supporting screeners in the field. Also at these facilities are automated on-line training/screening performance metrics servers. The secure facilities may be run under United States Department of Defense security standards and may be staffed with fully security cleared operators, particularly at the expert analysts workstations. These workstations are provided with real time connection to the screening process, both locally and out to the screeners via voice, image, video and text communication. The analysis facility has local copies of known threat data, as well as secure connectivity to appropriate governmental agencies. The system combines real time access to experts with the least traveler inconvenience or impact. The system may be used, for example at airports during check-in, gate-entry-screening, boarding, or baggage claim. In further embodiments, the system may be used in a wide variety of environments where the accurate and rapid identification of individuals is required such as any secure entry or access facility.
[0022] With reference to FIG. 4, the system begins (step 400 ) when a subject to be screened walks up to a screener at, for example, an airline ticket counter at an airport or an airline gate screening security station. In various embodiments, the screener may be required to log in and verify their own identity via the biometric analysis system. As shown in FIG. 4, during operation the screener follows a script and looks directly at the subject and asks to see the subject's ticket. When the system hears the screener say the word “ticket” (step 402 ) it takes a picture of whatever the screener is looking at at that moment. The image 406 of the subject that is taken by the camera will be a close up picture in full view of the subject's face and/or eye from a front-on direction. The screener should be trained to not say the word “ticket” until the subject is looking at the screener. In various embodiments, the system may permit the picture to be retaken if the subject fails to look toward the screener by again stating the word “ticket” or by recognizing some other pre-arranged command, such as “look at me, please” if necessary. The image 406 is recorded by the computer 22 . In further embodiments, the system may also automatically request that the screener re-take a picture, for example, if the biometric processing results in an ambiguity.
[0023] The screener then asks for some photo-identification, and while looking at the photo-identification the screener asks whether the address on the photo-id is the current address. The system hears the word “address” (step 408 ) and takes a photograph (step 410 ) of the photo-id that the screener is looking at. The photograph of the identification card 412 is also recorded by the computer 22 . The screener then looks at the ticket and reads the flight information out loud (e.g., “I see that you are on Flight 100 to Washington D.C.”). When the system hears the word “flight” (step 414 ) it takes another picture (step 416 ), this time of the ticket 418 , which is recorded by the computer 22 . Each of the pictures 406 , 412 and 418 are recorded in seconds, without interrupting the normal flow of passenger interaction. The pictures taken by the camera 14 are shown on the display as illustrated in FIG. 3 at 32 , 34 and 36 respectively, and are processed for transmission to the central facility. Biometric analysis may be performed by each computer 22 or preferably sent to the central facility for biometric analysis as well.
[0024] As shown in FIG. 5, each screener 8 has a data collection device 10 that is attached to a computer 22 that communicates via wireless communication to a central facility (optionally via a local wireless transmitter/receiver station 50 ). The central facility includes a firewall 52 , a central transmitter/receiver station/server 54 , and a number of high speed LAN/SAN data storage and analysis processors. The central facility may also include an interactive and automated on-line screener training/performance metric system 58 that monitors the performance of each screener. The analysis processors 56 are also coupled to a bank of analysts work stations 60 for providing real time expert analysis support for the screeners via two way communication. The analysts stationed at the work stations 60 provide backup analysis in the event that the biometrics analysis is not fully satisfactory, and provide question and answer support/training for the screeners. The system may also include access to information from a Federal information link 62 such as to the Federal Bureau of Investigations.
[0025] While the ticket and photo-id are being captured, the real-time analysis system at the central facility runs the picture 406 of the subject's face, or a mathematical representation of the face that has been extracted from the picture at either the screener or central site, against the known database of high-risk individuals. If there is no match (step 420 ) then a message is sent to the screener's device, and the screener receives an indication in field 40 of FIG. 3 that the subject is cleared and free to go. Typical biometric analysis systems employ a variety of test characteristics that together provide a numerical number, e.g., a match of x out of y characteristics. A match is typically defined as a range (m-y) such that numbers in the range (m<x<y) indicate a match. A match is strong if the number x is close to y, and weak if the number x is close to the threshold m.
[0026] Referring again to FIG. 4, which illustrates a watchlist application where a subject is being compared to known high risk individuals, if there is a match, the system determines whether or not the match is strong or weak (step 422 ). If the match is strong (step 422 ), then the system prompts the screener to not let the subject pass and to contact security immediately (step 424 ) for further questioning or retention. In certain embodiments, the system may itself contact security immediately to assist the screener. If there is a match at step 420 , but the match is weak (step 422 ), then the system automatically involves one or more experts (step 426 ) that are stationed at work stations 60 to assist in the analysis. The experts review the images and data in real time, and contact with screener with instructions to either clear the individual or to contact security. The system then ends (step 428 ) and begins anew with the next subject to be screened. Even if the expert analysts are involved, the screening process should require only seconds to fully execute. The system may also automatically involve one or more experts if the individual with whom a match appears to exist is a known high risk individual regardless of whether the match is strong or weak. When used for verification purposes (i.e., one to one matching as opposed to one to many matching), an index may be collected from the subject as via a barcode. This allows the system to check the current person against their previously enrolled identity.
[0027] The system is not required to utilize any single biometric characteristic such as facial recognition, and may be modified to capture and review other biometric information such as voice prints and iris scanning. In any event, the benefits of both biometric analyses and the use of expert analysts in real time significantly improves results for minimal costs. As shown in FIG. 6, the packet of information that is sent to the central facility for any particular subject includes the biometric information as well as copies of the pictures taken of the subject's face 406 , photo-id 412 and photograph of the ticket 418 . As shown in FIG. 7, each expert analyst station may include the above as well as any pertinent classified information 70 that is available only to the expert analysts.
[0028] The present invention provides high quality data capture and screening by leveraging the interaction between screening personnel and people being screened. Biometric data collection devices that are worn by the screener rely on the proximity and voice interaction between the screener and subject to obtain very reliable biometric data. The collection devices also communicate with a central control system for full analysis and reporting of the biometric data.
[0029] The visual prompting of the screener, in synchronization with the collection system, yields a systematic, uniform, natural, efficient and optimal data collection process. This increases the likelihood of detecting a known high-risk individual, and minimizes the number of false positive identifications. The system also reduces the required level of skill of the screeners that are in contact with the persons to be identified. Duplicate screeners, in fact, may even be employed at different stations in an airport, such as check-in, gate-entry, boarding and baggage claim. Further, the system may provide a safeguard that ensures that each passenger boarded a plane, that their luggage is on the plane, and that the luggage is later claimed by the correct person.
[0030] The real time automated switching of the screening from a totally automated biometric decision process, to an expert-in-the-loop process, allows any false match problems to be handled in an efficient manner. By utilizing experts, false matches may be cleared in seconds and resources may be utilized more efficiently to identify high-risk individuals.
[0031] By capturing the biometric data and identification and travel documents at the same time, a complete data set is efficiently and economically captured for each individual. By analyzing these data sets on a per screener basis, it is possible to discern areas of each individual screener's performance that need improvement. The system permits direct communication between the screeners and the experts. By training screeners using systems of the invention, greater efficiency may be achieved in both the screening and training of screeners.
[0032] As mentioned above, biometric data acquisition techniques other than facial recognition may also be employed. The easiest system for the subject to interact with is a non-contact biometric system such as facial recognition, where the subject needs only to be within a field of view of the facial recognition camera to have his or her face acquired and analyzed. Another non-contact method is voice verification, where the subject only needs to be within the range of the microphone being used to capture the voice. A drawback, however, of these non-contact biometric data acquisition techniques is that the quality and consistency of the capture may be highly variable. This variability in the captured data, in turn, causes the matching algorithms to have poor performance. Another non-contact biometric technique is iris recognition, which has much less variability in the matching process, but capturing a high quality image is quite difficult due to the small size of the iris. Further, contact based biometrics such as finger imaging, have much less of a problem capturing the appropriate part of the subject even at the proper resolution, but suffer from problems associated with having a large number of people touch the same sensor over an extended period of time, in addition to trying to quickly acquire finger image(s) that are properly aligned.
[0033] In accordance with a further embodiment of the invention, an identity verification system may employ a first biometric acquisition and analysis, followed by a secondary biometric acquisition and analysis in certain cases as discussed in more detail below. The secondary biometric information may also be input to the system, and this feedback may permit the primary biometric analysis system to better learn a subject's identity over time and therefore become more efficient.
[0034] For example a system of the invention may employ a contact biometric data acquisition system such as the fingerprint capture sensor device shown in FIGS. 8 A- 8 C fingerprint capture device 80 includes a pair of fingerprint sensors 82 and 84 mounted on oppositely facing surfaces such that the device may be squeezed by a subject when a subject's thumb and forefinger are placed on the sensors 82 and 84 . The device also includes a light source 86 and sensor contacts 86 that indicate that the subject is squeezing the device and thereby firmly pressing the thumb and forefinger against the respective sensors. The sensors are also coupled to a sensor output wire 90 for coupling to a communication system such as that shown in FIGS. 1 - 7 . The sensors record the image that is acquired from the finger, and the light 86 alerts the subject to the status of the capture process. The sensors may employ capacitive, optical or other finger image capture technologies. In a preferred embodiment, the sensors 82 and 84 are relatively inexpensive and easy to replace. This is preferred not only for hygienic reasons, but also to thwart efforts by subjects to damage or alter the sensors.
[0035] The device 80 allows for the capture of more than one finger at a time, automatically aligns the fingers with the sensors 82 , 84 , and further ensures that the correct amount of pressure is applied by the subject. The device permits the sensors to be squeezed (e.g., rotated about a pin 92 ) against a spring to a stop position, e.g., when the sensor contacts 86 abut one another. The subject is then notified via audio or light that the capture is complete and releases the device. This method permits the collection of correctly positioned finger images and hence leads to better recognition results. Other contact biometric data acquisition sensors may involve sending light through a person's skin to uniquely identify individuals, such as by using the LIGHTPRINT sensor product sold by Lumidigm, Inc. of Albuquerque, N. Mex.
[0036] As shown in FIGS. 9A and 9B, a method is accordance with a further embodiment of the invention involves the process of primary biometric data acquisition (steps 900 - 924 ) similar to the data acquisition process described above with reference to steps 400 - 424 of FIG. 4. If the analysis of the biometric data provides a strong match (step 922 ) then the program directs that the operator is to notify local security (step 924 ). If, however, the match is not strong (step 922 ) then the program directs the operator to acquire secondary biometric data as shown in step 930 in FIG. 9B. The secondary biometric data acquisition technique may involve contact biometric data such as by using the finger print capture sensor device 80 shown in FIG. 8. In other embodiments, the secondary biometric data acquisition technique may involve non-contact biometric data acquisition. If there is no match with the secondary biometric data, then the program returns that there was no match and ends (step 928 ). If there is a match with the secondary biometric data, then the program determines whether the match is a strong match (step 934 ) similar to the procedure discussed above with respect to the primary biometric data analysis.
[0037] If the match is not strong, the system may then proceed to invoking the expert analysts at the central facility (step 936 ) as discussed above with respect to step 426 in FIG. 4. If the secondary biometric analysis provides a strong match, then the system adds the primary set of biometric data to the databases in the central facility (step 938 ). By adding another set of primary biometric data to the central facility, the system provides helpful feedback with respect to the primary biometric data. This feedback permits the system to learn to better recognize individuals using the primary biometric data, and therefore permits the system to learn as it operates and such learning is independent of the remote computers on each screener or operator. In further embodiments, the system may permit the primary biometric system to learn via neural network feedback. Such feedback may be performed automatically and may further be conducted based on information from the expert analysts—either with or without using the secondary biometric system. Over time, this may considerably improve the performance of the primary biometric system.
[0038] The present invention not only optimizes the quality of the captured data presented to biometric algorithms, but it also allows the operator to select the easiest to use biometric that may be used in a given situation. This may allow non-contact biometric acquisition technique to be used in a first pass and a contact or alternate non-contact biometric acquisition technique to be used in a second pass if the first pass biometric does not achieve the desired results due to problems with the collection of the data for the first pass biometric. For example, if the first pass biometric works 90% of the time and takes 5 seconds, and a second pass biometric takes 15 seconds and works for 95% of the 10% that did not work in the first pass, then overall the two passes of biometrics will work for 99.5% of the subjects being verified. Moreover, the average time to complete the biometric data acquisition will be significantly less time than the time required if the secondary biometric acquisition technique was employed all of the time (as the first pass technique). This reduced time produces much shorter queues of subjects being verified, provides better overall customer experience, and much lower costs for screening activities.
[0039] As mentioned above, the system permits interactive training of screening personnel based on their on-going performance. Quality assurance may also be improved by using an identity verification system of an embodiment of the invention. In particular, quality assurance personnel may record the complete interaction between a subject and a screener via the wearable computer and upload the interaction to the central facility. The quality assurance personnel may then play back the interaction and evaluate performance. In accordance with an embodiment, the system may provide the capability to immediately react to issues noted by a quality assurance personnel, by allowing the quality assurance personnel to assign an interactive multi-media training module to the field personnel (or screener). The field personnel are then prompted to participate in a training session at the next convenient time, such as when they log into their wearable computer at the start of their next shift. This centralized quality assurance and training capability permits large organizations to assure that their field personnel are providing high quality customer service in a method that is considerably more efficient and effective than sending quality assurance personnel to the field for auditing and training purposes. The quality assurance personnel may collect the field data on a periodic or directed basis and the customer or subject interactions may be recorded via the wearable computer. Such a quality assurance routine may be conducted over an extended period of time for the convenience of the quality assurance personnel and the screeners. For example, the interaction may be automatically uploaded to the central facility at scheduled times, then viewed by a quality assurance person at any later time. After reviewing a transaction, the quality assurance person may select and transmit to the screener a training module (e.g., to improve the quality of pictures being taken by the screener). The screener may then be prompted to run the training module when he or she next signs onto the system. Any initial training may also be similarly conducted without requiring the screener to travel to the central facility.
[0040] Those skilled in the art will appreciate that numerous modifications and variations may be made to the above disclosed embodiments without departing from the spirit and scope of the invention.
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A security identification system is disclosed for providing information regarding subjects to be identified. The system includes a primary biometric data input unit for receiving primary biometric data regarding a subject, a primary biometric analysis unit, a secondary biometric data input unit, a secondary biometric analysis unit, and a security clearance output unit. The primary biometric analysis unit is for analyzing the primary biometric data and comparing it against known biometric data in a database. The primary biometric analysis unit is also for providing primary match data that is indicative of whether a match exists with respect to the primary biometric data and whether the primary match data is above a minimum primary biometric data correlation threshold. The secondary biometric data input unit is for receiving secondary biometric data regarding the subject when the primary match data is below a minimum primary biometric data threshold. The secondary biometric analysis unit is for analyzing the secondary biometric data and comparing it against known biometric data in the database. The secondary biometric analysis unit is also for providing secondary match data that is indicative of whether a match exists with respect to the secondary biometric data and whether the secondary match data is above a minimum secondary biometric data correlation threshold. An automatic feedback mechanism is provided between the secondary and primary biometric to continually improve the performance of the primary biometric. The security clearance output unit is coupled to the primary biometric data analysis unit and to the secondary biometric data analysis unit for providing an indication of whether the subject is cleared.
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RELATED APPLICATION
This application is a continuation-in-part of copending application Ser. No. 120,861, filed Feb. 12, 1980, which is assigned to the same assignee as the present invention.
BACKGROUND OF THE INVENTION
In Watt, U.S. Pat. No. 3,936,557, are described blends of epoxide materials which, although essentially free of volatile solvents, are liquid and tractable for coating and related applications. The blends comprise epoxy prepolymers of the type glycidyl-bisphenol-A resins, epoxidized novolaks, polyglycidyl ethers, and alicyclic diepoxides, blended with bis(epoxycycloalkyl) esters. The compositions include a cationic polymerization initiator, in particular a radiation sensitive catalyst precursor, such as an aromatic diazonium salt of a complex halogenide. In use, the compositions are coated on a substrate, followed by the application of energy, through heating or through irradiation, to effect substantial polymerization of the epoxidic materials of the coating. A related, relevant disclosure is Schlesinger, U.S. Pat. No. 3,708,296. In Crivello and Schroeter, U.S. Pat. No. 4,026,705, it is disclosed that certain radiation-sensitive diaryl iodonium complex salts, such as diphenyliodonium hexafluoroborate, can be incorporated into epoxy resins to produce in one package radiation-curable compositions. Related teachings are found in Barton, U.S. Pat. No. 4,090,936. Such catalyst systems are more stable than the complex diazonium compounds. In Crivello, U.S. Pat. No. 4,173,551, diaryliodonium salts are disclosed to be effective thermal initiators for polymerization of epoxides when used in combination with various co-catalysts, such as copper salts. All of the foregoing patents are incorporated herein by reference.
It has now been found possible to formulate improved epoxide coatings if a novel and judicious choice is made of the type of epoxy compounds used, the type of catalyst employed, the amount of solvent used and the type and amount of pigment loadings employed. With the new coatings, no need of thinner reduction to application viscosity is necessary: Application can be made surprisingly easily at solids contents approaching 100 percent by weight. The coatings can be formulated, in general, with any conventional pigment and, if a tin salt is used, unique advantages in terms of room temperature cure rate will result. It is a principal object to provide the finisher with the option to totally eliminate the need for organic solvents. If the finisher still needs a solvent, the composition can still function with less than 10 percent by weight--which is well within Environmental Protection Agency regulations. As mentioned, it is remarkable that all these features are achieved at application viscosity, permitting the finisher to apply extremely heavy films with ease. In addition, as has also been discovered, the embodiments using tin salt co-catalyst will cure at room temperature. These unique and versatile coatings depend on the presence in the composition of the epoxide, the complex catalyst, the copper salt co-catalyst and the pigment, and such is the subject matter of this invention.
DESCRIPTION OF THE INVENTION
According to the present invention there are provided pigmented, high-solids content, curable compositions comprising
(a) an epoxide prepolymer blend comprising
(i) a diglycidyl ether of cyclohexanedimethanol,
(ii) a diglycidyl ether of bisphenol-A,
(iii) a polyepoxidized phenol or cresol novolak,
(iv) a polyglycidyl ether of a polyhydric alcohol,
(v) an epoxidic ester having two epoxycycloalkyl groups, or
(vi) a mixture of any of the foregoing; and
(b) from 0.5 to 35 parts by weight per 100 parts by weight of (a) and (b) combined of a catalyst comprising
(i) a diaryliodonium salt of the formula
[(R).sub.a (R.sup.1).sub.b I].sub.c.sup.+ [MQ.sub.d ].sup.-(d-e)
wherein R is a monovalent organic radical, R 1 is a divalent aromatic organic radical, M is a metal or metalloid, Q is a halogen radical, a is a whole number equal to 0 or 2, b is a whole number equal to 0 or 1 and the sum of a+b is equal to 2 or the valence of I, c=d-e, e equals the valence of M and is an integer equal to 2-7 inclusive and d>e and is an integer having a value up to 8; and
(ii) from 0.01 part to 10 parts, per part of
(i) of a copper salt; and
(c) from 10 to 100 parts by weight, per 100 parts by weight of (a) and (b) of a pigment.
In preferred features, there will also be included (d) a tin salt co-catalyst, preferably stannous octoate, in an effective amount, for example from 0.1 to 10 parts per part of (b)(i) and (b)(ii) combined.
With respect to the ingredients, the diglycidyl ether of cyclohexanedimethanol (a)(i) has the formula: ##STR1## It can be made in conventional ways, e.g., by the reaction of epichlorohydrin with 1,4-cyclohexanedimethanol. It also is commercially available, e.g., from Wilmington Chemical Co., under the tradename Heloxy MK-107.
Preferred blends may include one or more of the following:
(a)(ii) the well-known reaction product of epichlorohydrin and a diphenolic compound, e.g., bisphenol-A. This is a viscous liquid resin, available from a number of sources, e.g., from Shell Chemical Co., under the tradename EPON 828;
(a)(iii) a polyepoxidized phenol or cresol novolak, such as the well-known products having average molecular weights in the vicinity of 1000, and epoxy equivalent weights in the range of 160 to 200 (frequently about 170-180), commercially available, e.g., from Dow Chemical Co., under the tradename D.E.N. 438;
(a)(iv) a polyglycidyl ether of a polyhydric alcohol, such as the diglycidyl ether of 1,4-butanediol, the diglycidyl ether of diethylene glycol, the triglycidyl ether of glycerol, and the like. The first-mentioned is commercially available, e.g., from Ciba-Geigy under the tradename Araldite RD-2; or
(a)(v) an epoxidic ester having two epoxycycloalkyl groups, such as 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane carboxylate and bis(3,4-epoxy-6-methylcyclohexylmethyl)adipate, both available from Union Carbide Co., under the respective tradenames ERL 4221 and ERL 4289, the former being available as well from Ciba-Geigy, under the tradename CY-179.
Preferred blends of epoxides will comprise from about 15 to 90% by weight of epoxide (a)(i) and about 85 to 10% by weight of one or more of the other enumerated epoxides.
In the diaryliodonium component of the catalyst, radicals embraced by R can be the same or different aromatic carbocyclic radicals having from 6 to 20 carbon atoms, which can be substituted with from 1 to 4 monovalent radicals selected from C.sub.(1-8) alkoxy, C.sub.(1-8) alkyl, nitro, chloro, etc. R is, more particularly, phenyl, chlorophenyl, nitrophenyl, methoxyphenyl, pyridyl, etc. Radicals included by R 1 are divalent radicals such as: ##STR2## where Z is selected from --O--, --S--, ##STR3## (CH 2 ) n , ##STR4## R 2 is C.sub.(1-8) alkyl or C.sub.(6-13) aryl, and n is an integer equal to 1-8, inclusive.
Metals or metalloids included by M in formulas above are transition metals such as Sb, Fe, Sn, Bi, Al, Ga, In, Ti, Zr, Sc, V, Cr, Mn, Cs, rare earth elements such as the Lanthanides, for example, Ce, Pr, Nd, etc., Actinides, such as Th, Pa, U, Np, etc., and metalloids, such as B, P, As, etc. Complex anions included by MQ d - (d-e) are, for example, BR 4 - , PF 6 - , AsF 6 - , SbF 6 - , FeCl 4 = , SnCl 6 - , SbCl 6 - , BiCl 5 = , etc.
Iodonium salts included by the above formulas are, for example: ##STR5##
The preferred iodonium salt is diphenyliodonium hexafluoroarsenate or diphenyliodonium hexafluorophosphate.
Iodonium salts of the type used herein can be made by the procedure disclosed in Crivello, U.S. Pat. No. 3,981,897, incorporated herein by reference, wherein contact between an aryl halonium bisulfate and the corresponding hexafluoro acid or salt can be effected under aqueous conditions.
Copper salts which can be used as component (b)(ii) include, for example, Cu(I) salts such as copper halides, e.g., Cu(I) chloride, etc., Cu(II) salts such as Cu(II) benzoate, Cu(II) acetate, Cu(II) stearate, Cu(II) gluconate, Cu(II) citrate, etc. Copper(II) naphthenate is preferred.
Suitable tin salts co-catalysts are stannous salts of carboxylic acids of the formula: ##STR6## where R 3 is a monovalent organic radical selected from C.sub.(1-18) alkyl and C.sub.(6-13) aryl. Illustrative organic acids are acetic acid, 2-ethylhexanoic acid, hexanoic acid, oleic acid, stearic acid, palmitic acid, benzoic acid, salicylic acid, and the like. The preferred tin salt is stannous octoate.
The epoxidic resins can be used alone or in combination with reactive diluents, in known ways. For example, such diluents include phenyl glycidyl ether, 4-vinylcyclohexene dioxide, limonene dioxide, 1,2-cyclohexene oxide, glycidyl acrylate, glycidyl methacrylate, styrene oxide, allyl glycidyl ether, etc. Other compounds can also be included, e.g., epoxysiloxane resins, epoxypolymethanes and epoxypolyesters. Other conventional modifiers include amines, carboxylic acids, thiols, phenols, alcohols, etc. Flexibilizers such as hydroxy-terminated polyesters can also be used.
The pigment component (c) can vary widely. Any conventional pigment can be used at conventional levels, e.g., 10-200 parts per 100 parts of composition. Preferably the pigment/binder ratio will be from 1:1 to 1:5, and especially preferably it will be about 1:2. Suitable pigments include titanium dioxide, lamp black, red iron oxide, mixtures thereof, and the like.
Conventional paint making techniques can be used to make the compositions of this invention. These techniques are well known to those skilled in this art. For example, the pigment, epoxy prepolymer and a very small amount of solvent, e.g., cyclohexanone, can be milled or ground, e.g., in a Cowles mixer, to produce a master grind containing, e.g., 55 to 65 weight percent pigment, 25-35 weight percent of epoxidic prepolymer; and a solids content of from about 80 to about 99 weight percent, preferably above 85 weight percent. Separately, a catalyst solution is prepared from a solvent, e.g., methyl ethyl ketone, the iodonium salt, e.g. diphenyliodonium hexafluoroarsenate or diphenyliodonium hexafluorophosphate, and the copper co-catalyst, e.g, 6% copper naphthanate. Suitable such solutions comprise about 60 to 80 weight percent solvent, 2 to 10 weight percent copper salt and 15-40 weight percent of iodonium salt. The final composition is formulated by providing formulations with additional epoxide, the master grind, the catalyst solution, and optional stannous salt. The final pigment/binder ratio is for example about 1:2 and a useful viscosity is 20 to 40 seconds in a Zahn #3 cup. This can be readily achieved, for example, by blending 50 parts of epoxide, e.g., a cycloaliphatic epoxide, e.g., Union Carbide's ERL-4221, or a BPA-type epoxy, such as Shell Chemicals EPON 828. If stannous octoate is present, the compositions should be freshly prepared because the pot life is generally less than one hour. The pot life can be greatly increased by excluding the stannous octoate.
Conventional coating methods, e.g., brush, spray, dip, flow, etc. can be used. In general, thicknesses of 3-4.0 mils. of paint will give excellent combination of protection, life and economy. The coatings are curable at room temperature, especially if stannous salts are included, and also they are bakeable at elevated temperatures, e.g., for 5 to 20 minutes at 300°-500° C. They are corrosion resistant, flexible and surprisingly resistant to strong solvents, such as methyl ethyl ketone and dimethyl formamide.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following examples illustrate the practice of the present invention. The claims should not be limited to them in any manner whatsoever.
EXAMPLE 1
A master grind is prepared in a Cowles mixer from the following:
______________________________________Components Parts by Weight______________________________________bis-glycidyl ether ofcyclohexane dimethanol.sup.a 877pigment, titanium dioxide 260wetting agent.sup.b 10cyclohexanone 140______________________________________ .sup.a Heloxy MK107 (Wilmington Chemical Co.) .sup.b AntiTerra U (BykMallinckrodt Co.) The pigment comprises 57.48 weight percent, epoxy 28.97 weight percent, and the solids content is 86.79 weight percent.
A catalyst solution is prepared from the following:
______________________________________Components Parts by Weight______________________________________methyl ethyl ketone 74diphenyliodonium hexafluoro-arsenate 20copper naphthanate 6______________________________________
The following coating composition is prepared:
______________________________________Components Parts by Weight______________________________________bis-glycidyl ether of bisphenol Aand small amount of copper stearate.sup.c 50master grind (above) 50xylene 5catalyst solution (above) 1.3stannous octoate 1.2______________________________________ .sup.c Arnox 3110 (General Electric Co.)
The intimate blend has a viscosity of 40 seconds in a Zahn #2 cup, a pigment/binder ratio of 1:2, and a solids content of 88 weight percent.
It is coated onto a cleaned and treated metal panel and cured for 5 minutes at 400° F. The thickness of the coating is 3-4.0 mils., the pencil hardness is 6H; it withstands 200 methyl ethyl ketone rubs; the reverse impact is 5 in. lbs. and after 72 hours of soaking in dimethylformamide, there is only a very, very slight softening effect.
EXAMPLE 2
The following coating composition is prepared:
______________________________________Components Parts by Weight______________________________________3,4-epoxycyclohexylmethyl3,4-epoxycyclohexane carboxylate.sup.a 50master grind (Example 1) 50catalyst solution (Example 1) 7stannous octoate 1.4______________________________________ .sup.a ERL4221 (Union Carbide Co.)
The intimate blend has a viscosity of 26 seconds in a Zahn #2 cup, a pigment/binder ratio of 1:2, and a solids content of 88 weight percent.
It is coated onto a cleaned and treated metal panel and cured for 5 minutes at 400° F. The thickness of the coating is 3-4.0 mils., the pencil hardness is 7H; it withstands 200 methyl ethyl ketone rubs; the reverse impact is 10 in. lbs. and after 72 hours of soaking in dimethyl formamide there is no adverse effect whatsoever. Example 2 is coated on cold rolled steel (untreated) and cured for 5 minutes at 400° F. This system goes 1200 hours in the 5% salt fog cabinet without blistering or creeping.
EXAMPLE 3
A master grind is prepared in a Cowles mixer (15 minutes; 5500 rpm) from the following;
______________________________________Master Grind Parts by Weight______________________________________ERL-4221.sup.a 510PCP-0200.sup.b 175Esterdiol 204.sup.c 135Byk-P-104S.sup.d (Byk-P-104S) 2Foam Kill 369-Q.sup.e 2Heloxy 68.sup.f 50titanium dioxide 750lamp black 50______________________________________ .sup.a A difunctional cycloaliphatic epoxide (Union Carbide Co.) .sup.b A poly caprolactone diol (Union Carbide Co.) .sup.c A low molecular weight ester diol (Union Carbide Co.) .sup.d Wetting agent recommended for use with epoxides (BYK Mallinckrodt) .sup.e Antifoaming agent (Crucible Chemical Co.) .sup.f The diglycidyl ether of neopentyl glycol (Wilington Chemical Co.)
A catalyst solution, Catalyst A, is prepared from the following:
______________________________________Catalyst A Parts by Weight______________________________________diphenyliodonium hexafluoro-phosphate 210ERL-4221 800methyl ethyl ketone (MEK) 80______________________________________
Additions are made to the master grind to form Part A, as follows:
______________________________________Part A Parts by Weight______________________________________master grind (above) 1674Heloxy MK 107.sup.a 63Catalyst A (above) 175Total 1912______________________________________ .sup.a The diglycidyl ether of cyclohexanedimethanol (Wilmington Chemical Co.)
A second catalyst solution, Part B, is prepared as follows:
______________________________________Part B Parts by Weight______________________________________ERL-4221 729stannous octoate 53copper naphthanate 37Solvesso 150.sup.a 20Butyl Cellosolve.sup.b 20______________________________________ .sup.a A hydrocarbon solvent .sup.b Butoxy ethanol (Union Carbide Co.)
Parts A and B are mixed in a 4:1 ratio and applied to a cleaned and treated steel panel.
The application solids content of this composition is 97%. The application viscosity is 26 seconds in a Zahn #3 cup. The pot life is 10 minutes.
The freshly-coated panel is baked 25 minutes at 180° F., then allowed to cool 30 minutes. The thickness of the coating is 3.0 mils., the pencil hardness is 5H; it withstands 100 methyl ethyl ketone rubs with only a slight softening; the reverse impact is 10 in. lbs.
The foregoing examples demonstrate that cycloaliphatic and BPA-type epoxides, pigmented and catalyzed with diaryliodonium complex salts, and copper salts produce extremely useful coatings of outstanding durability. These coatings are formulated to be easily applied at solids contents approaching 100 percent by weight with viscosities less than 40 second Zanh #3. These coatings are seen to exhibit great resistance to strong solvents, such as methyl ethyl ketone and dimethyl formamide. These coatings also yield basically the same properties when force-cured as low as 180° F. or air dried. The degree of cure is directly related to the addition of stannous octoate when curing at low temperatures.
Many variations will suggest themselves to those skilled in this art. All such obvious variations are within the full intended scope of the appended claims.
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Novel coating systems comprising high-solids content blends of epoxy prepolymers, a catalyst complex comprising a complex iodonium salt and a copper salt, and a conventional pigment. The compositions cure rapidly to highly chemically resistant, tough coatings.
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RELATED APPLICATIONS
This application is a Continuation-In-Part Application of Nonprovisional patent application Ser. No. 12/982,669 filed Dec. 30, 2010 entitled “FLOATING BIOREACTOR SYSTEM”, which is related to U.S. Provisional Patent Application Ser. No. 61/317,715 filed Mar. 26, 2010 entitled “FLOATING BIOREACTOR SYSTEM”, which is incorporated herein by reference in its entirety, and claims any and all benefits to which it is entitled therefrom. This Application is also related to PCT Patent Application No. PCT/US11/58139 filed Oct. 27, 2011 entitled “FLOATING BIOREACTOR SYSTEM”, which is incorporated herein by reference in its entirety, and claims any and all benefits to which it is entitled therefrom.
FIELD OF THE INVENTION
The present invention pertains to an aeration device and microbial bioreactor system for use in a liquid medium. More specifically, the invention relates to floating and/or submerged bioreactor systems that can be adapted to applications for treatment of water in aquariums and domestic septic systems, as well as water, leachate and industrial waste in rivers, streams and creeks.
BACKGROUND OF THE INVENTION
Subsurface aeration seeks to release bubbles at the bottom of the pond and allow them to rise by the force of gravity. Diffused aeration systems utilize bubbles to aerate as well as mix the pond. Water displacement from the expulsion of bubbles can cause a mixing action to occur, and the contact between the water and the bubble will result in an oxygen transfer.
Bioreactors are also designed to treat sewage and wastewater. In the most efficient of these systems there is a supply of free-flowing, chemically inert media that acts as a receptacle for the bacteria that breaks down the raw sewage. Aerators supply oxygen to the sewage and media further accelerating breakdown. In the process, the liquids Biochemical Oxygen Demand BOD is reduced sufficiently to render the contaminated water fit for reuse. The biosolids are collected for further processing or dried and used as fertilizer, agricultural feed, etc.
Subsurface aeration, bioreactors and most likely a combination of both are commonly employed to treat sewage water, recycle wastewater and other water treatment applications both industrially or domestically.
The need exists for adaptation of a combination aerator and bioreactor for use in an enclosed system such as an aquarium or a domestic septic tank system.
SUMMARY OF INVENTION
The present invention relates to a system that consists of an apparatus for aerating and circulating a liquid medium and at the same time an apparatus for the continuous microbial bio-remediation of organic waste in rivers, sewers and other waste laden environments utilizing in-situ microbial seeding.
The present invention is a microbe bio-reactor designed to work in open water such as lakes and ponds and in lagoons and tanks to clean up water biologically. It can clean tip water in a short amount of time and will be energy efficient. It works by having imbedded microbes in, and these are stores in its main reactor chamber that is a slotted pipes.
The core of its main reactor chamber is a perforated hose. Air is pumped into the perforated hose and is released all along the pipe. The air is diffused in the water surrounding this and this causes the water to rise and it circulate the microbe with the dirty water. This feeds the microbes imbedded in the media and this causes the microbes to replicate and thus releasing billions of microbes every second. As the microbes are release upward it is oxygenated greatly by the main hose diffusers and this causes the microbes to multiply even much more.
At the top of the water, the water is pushed out and is mixed causing even more microbial growth. At the surface of the water, it again is exposed to the atmosphere and is not only evenly spread out, it is again oxygenated and thus multiplying organisms even more.
The microbes create an even larger zone of air and/or oxygen transfer to the water, thus facilitating even more microbial growth. Thus, all along the water flow cycle, the present invention generates even more microbes in the expense of minimum electricity usage of the approximate range of 2 HP.
As the water is pulled down under the tank or water body, it pulls down not only microbes but increases dissolved oxygen such that microbial growth at the bottom of the tank or water body is greatly enhanced. Thus, water is cleaned and revived. In addition, the process removes hydrogen sulfide present in the contaminated water or other liquid medium. The process also reduces methane, a green house gas, formation to help preserve the environment.
An advantage of the present invention is that biosolids and/or sludge handling is eliminated. The biosolids are eaten up and consumed by the microbes, thus eliminating the need for sludge and biosolids handling equipment, disposal, etc. In addition, having the microbes on the surface of the water increases the efficiency of oxygen transfer in the bioreactor.
Another object of the present invention is the very small amounts of electricity consumed due to high efficiency which helps to reduce energy consumption.
Another object of the present invention is that the biosafety level one microbes can inhabit the micropores in the rocks and river beds of the streams and keep on improving even after the bioreactor is disengaged although the effect is much better to leave it in place.
Another object of the present invention is that even without expensive membrane filters, the bioreactor can be applied to sewage with results that clean waste water to bod less than 5 or less than 1 and then it is percolated and the treated waste water can recharge ground water.
Yet another object of the present invention is to provide systems and methods to clean aquariums without using chemicals which can be harmful to fish. Also, the present invention helps to reduce odors due to dirty aquariums. Moreover, the present invention helps to reduce the need to clean aquariums due the biofilm built up on the internal surfaces. Consequently, the present invention helps to reduce labor cost, water cost and other costs related to frequent cleaning of aquariums and other fish habitats.
Yet another object of the present invention is to provide systems and methods to clean domestic septic systems efficiently to reduce the need to remove built up sludge to a frequency of not more than once every 6 months to 5 years. The present invention also helps to reduce odor from septic tanks.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a representative upper front perspective view of floating bioreactor system 100 of the present invention.
FIG. 1B is a representative graph showing the relationship between Standard Oxygen Transfer Rate [SOTR] and various Total Dissolved Solids [TDS] values of the liquid medium.
FIG. 1C is a representative graph showing the relationship between Standard Aeration Efficiency [SAE] and various Total Dissolved Solids [TDS] values of the liquid medium.
FIG. 1D is a representative graph showing the relationship between Standard Aeration Efficiency [SAE] and various Salt Concentration [TDS] values of the liquid medium.
FIG. 1E is a representative graph showing the relationship between Standard Aeration Efficiency [SAE] and various Salt Concentration [TDS] values of the liquid medium.
FIG. 2 is a representative upper front perspective view of an in situ bioreactor container 200 of floating bioreactor system 100 of the present invention.
FIG. 3 is a representative view showing the method of application of the floating bioreactor system 100 of the present invention.
FIG. 4A is a representative view showing one method of adaption of an alternative embodiment, viz. aquarium bioreactor and aerator system 400 .
FIG. 4B is a representative side view of bioreactor and aerator combo 401 of aquarium bioreactor and aerator system 400 .
FIG. 4C is a representative side partially exposed view of bioreactor and aerator combo 401 of aquarium bioreactor and aerator system 400 .
FIG. 5A is a representative view showing one method of adaption of an alternative embodiment, viz. home septic bioreactor and aerator system 500 .
FIG. 5B is a representative side view of home septic unit 501 of home septic bioreactor and aerator system 500 .
FIG. 5C is a representative side partially exposed view of home septic unit 501 of home septic bioreactor and aerator system 500 .
FIG. 6A is a representative view showing one method of adaption of an alternative embodiment, viz. aero dynamic mixer bioreactor and aerator system 600 .
FIG. 6B is a representative side view of aero dynamic mixer 601 of aero dynamic mixer bioreactor and aerator system 600 .
FIG. 7 is a representative view of the floating aquarium bioreactor and aerator system 700 of the present invention.
FIG. 8 is a representative view of the floating septic tank bioreactor and aerator system 800 of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The description that follows is presented to enable one skilled in the art to make and use the present invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be apparent to those skilled in the art, and the general principals discussed below may be applied to other embodiments and applications without departing from the scope and spirit of the invention. Therefore, the invention is not intended to be limited to the embodiments disclosed, but the invention is to be given the largest possible scope which is consistent with the principals and features described herein.
DEFINITION OF TERMS
Standard Oxygen Transfer Rate [SOTR]—Pounds of oxygen transferred to water per hour [lbs O 2 /hour]. SOTR is measured in clean water when the dissolved oxygen [DO] concentration is zero at all points in the water volume, the water temperature is 20° C., at a barometric pressure of 1.00 atm [101 kPa].
Standard Aeration Efficiency [SAE]—Standard Oxygen Transfer Rate per unit total power input. SAE is typically expressed as the pounds of oxygen transferred to the water per hour per HP [lbs O 2 /hour/HPwire], and is sometimes referred to as SAE Wire. SAE is used as a measure of how efficiently an aerator is transferring oxygen.
FIG. 1A is a representative upper front perspective view of floating bioreactor system 100 of the present invention. Floating bioreactor system 100 of the present invention has a housing 102 . In one embodiment, housing 102 is made of fiberglass that is strong enough to support the weight of the entire floating bioreactor system 100 without the assistance of buoyance and is not prone to corrosion, degradation in the presence of water and/or other liquid medium, including salt water or waste water with other chemicals. Housing 102 of floating bioreactor system 100 can be assembled by nuts and bolts or other optimal mechanical fastening means. As shown in FIG. 1A , a plurality of floats 120 are attached to housing 102 on both sides. The main function of floats 120 is to lend buoyance to the entire floating bioreactor system 100 such that the present invention is able to float and maintain an appropriate buoyance level within the liquid medium. Optionally, floats 120 are inflatable or otherwise adjustable so buoyancy and waterline of the overall housing 102 can be adjusted.
As shown in FIG. 1A , blower 104 is placed on top of housing 102 . In one embodiment, blower 104 is a 1.75 kW regenerative blower which is an ideal solution for moving large volume of air at lower pressures or near vacuum. The main function of blower 104 is to be an air source for the aeration process of the present invention 100 . Using blower 104 can be one of the most cost effective methods for producing pressure or vacuum. Filter 106 cleans particulate from the air that goes in and through blower 104 to avoid dust or oil in contact with diffuser grids 130 .
As best shown in FIG. 1A , blower 104 is connected to diffuser grids 130 via diverter 150 and subsequently hoses 152 . Hoses 152 are attached to diverter 150 to receive the necessary air for diffuser grids 130 . In one embodiment, diverter 150 spreads the air generated from blower 104 evenly to diffuser grids 130 via a plurality of hoses 152 . The main function of diffuser grids 130 is to create aeration within the liquid medium that the present invention 100 is trying to clean. In alternative embodiments, multiple diffuser grids 130 can be installed and connected to blower 104 to increase overall effectiveness and scale of cleaning power of floating bioreactor system 100 of the present invention.
For efficient aeration system, whether it is an aeration system or device splashes, sprays, or diffuses air, an important factor is how much surface area it creates. The surface area is where water/liquid medium contacts air and where oxygen transfer takes place. Smaller bubble size results in more surface area, which is why fine bubble aeration devices are superior in oxygen transfer than coarse bubble aerators. To maximize aeration efficiency in a system, an aerator must create fine bubbles while expending a minimum amount of energy. The main purpose is to have a high SOTR and SAE for the aeration system.
In one embodiment, there are a number of commercially available diffuser grids 130 that can be incorporated in the floating bioreactor system 100 of the present invention. Most of these models resemble what has been disclosed in U.S. Pat. No. 5,811,164, issued Sep. 22, 1998 to Mitchell entitled “AERATION PIPE AND METHOD OF MAKING SAME”, which is incorporated herein by reference in its entirety. One of the commercial models is Aero-Tube™ diffuser grids. One of the most important structure for the extremely high performance and efficiency of diffuser grids 130 is the adaptation of hose segments 132 which, through a unique combination of technique and raw material, creates numerous micro-pores 134 throughout the length of hose segments 132 . These micro-pores 134 create tiny air bubbles and hence high surface area, which allows the efficient transfer of air into the water. In one embodiment, diffuser grids 130 are made up of hose segments 132 . Preferably, hose segments 132 are made from thermoset polymer particles in a matrix of thermoplastic binder material, which may be made according to a method described in the '164 patent.
In one embodiment, the specifications of hose segments 132 are in the approximate range as follows: Outside Diameter, 1.00 inch (2.54 cm); Inside Diameter, 0.500 inch (1.27 cm); Wall Thickness, 0.250 inch (0.635 cm); Weight, 0.220 lbs per foot (0.327 kg per meter); Roll Length, 200 ft. (60.98 meters); Roll Weight, 44 lbs. (19.9 kg); Burst Pressure, 80 PSI (5.5 bar).
Due to the number of pores created during the manufacturing process, there is little resistance created when pushing air through hose segments 132 . Resistance equals energy demand hence diffuser grids 130 uses significantly less horsepower when compared with traditional methods of aeration such as bubblers, paddlewheels, aspirators, less efficient tubing, etc. Moreover, diffuser grids 130 bare tiny pore size which creates bubbles with extremely small diameters. The smaller the gas bubbles, the more efficiently they transfer oxygen into water. Small bubbles also take longer to rise once they are introduced into water. Slower rising, small-diameter bubbles mean more contact with the water and a much higher rate of oxygen transfer. By creating significantly smaller bubbles, more efficiently, diffuser grids 130 are able to deliver high rates of oxygen transfer [SOTR] and energy efficiency [SAE].
As shown in FIG. 1A , bioreactor pump 108 is also mounted on housing 102 . In one embodiment, bioreactor pump 108 is a relatively less powerful pump in the range of about 60 W that supplies air to the in situ bioreactor container 200 . Bioreactor hose 140 that connects bioreactor 200 also transfers air from bioreactor pump 108 to the bioreactor 200 for the biocarrier media therein. Air and nutrients are supplied to the microbial population which are located within the biocarrier media. In one embodiment, bioreactor 200 is secured at the bottom of housing 102 and underneath diffuser grids 130 to provide continuous in-situ addition of beneficial microbes directly within an environment to be treated thereby permitting optimized mineralization of waste being treated as well as acclimation of the microbes to such waste.
FIG. 1B is a representative graph showing the relationship between Standard Oxygen Transfer Rate [SOTR] and various Total Dissolved Solids [TDS] values of the liquid medium of both commercial diffuser grids 130 and traditional aeration device like paddle wheel. As best shown in FIG. 1B , diffuser grids 130 performs better than paddle wheel throughout the range of TDS from 0 to approximately 35,0000 mg/L. This demonstrates that using diffuser grids 130 is an effective, improved method for aeration [higher SOTR].
FIG. 1C is a representative graph showing the relationship between Standard Aeration Efficiency [SAE] and various Total Dissolved Solids [TDS] values of the liquid medium of both commercial diffuser grids 130 and traditional aeration device like paddle wheel. As best shown in FIG. 1C , diffuser grids 130 performs better than paddle wheel throughout the range of TDS from 0 to approximately 35,0000 mg/L. Proofing that using diffuser grids 130 is a much more cost efficient method for aeration [higher SAE].
FIG. 1D is a representative graph showing the relationship between Standard Aeration Efficiency [SAE] and various Salt Concentration [TDS] values of the liquid medium for most common aeration methods including Aero-Tube™. FIG. 1E is a representative graph showing the relationship between Standard Aeration Efficiency [SAE] and various Salt Concentration [TDS] values of the liquid medium for most common aeration methods including Aero-Tube™. An internationally recognized engineering firm conducted performance tests on the aeration tube in both fresh and salt water environments. In a controlled study, they compared an airlift aerator utilizing Aero-Tube™ technology with an equal horsepower paddle wheel and brush paddle wheel aerator, two of the most popular aeration technologies on the market today.
Aero-Tube™ performed extremely well in all areas, including its ability to transfer oxygen to water, expressed in terms of a standard oxygen rate [SOTR], and its efficiency in terms of pounds of oxygen per kilowatt-hour [the standard aerator efficiency or SAE Wire, rate].
In the fresh water testing, the Aero-Tube™ aerator exceeded the paddle wheel's energy efficiency [SAE Wire] by up to 2.6 times.
Aero-Tube™ aeration tubing performed even better in the salt water test. As the density of the water's salt content increased [from 5,000 mg to 35,000 mg], the oxygen advantage of the Aero-Tube™ system steadily rose. At 35,000 mg/L NaCl, the energy efficiency of Aero-Tube™ aerator was as much as 4.2 times the efficiency of the paddle wheel.
While performance of diffuser grids 130 may vary among different brands and models, in general diffuser grids 130 are considered one of the most effective and cost efficient aeration devices because nearly all of the energy used to deliver the air that goes through hoses 140 and hose segments 132 goes directly into the water/liquid medium. A paddle wheel, wastes energy by throwing water/liquid medium into the air to pick up oxygen.
FIG. 2 is a representative upper front perspective view of an in situ bioreactor tube or container 200 of floating bioreactor system 100 of the present invention. In summary, in situ bioreactor is a bio reactor paired with an aeration device such as a microbubble generator. The purpose of the microbubble generator is to generate highly oxygenated water which infuses microbes with the nutrients required to achieve very high levels of process and treatment effectiveness and efficiency. The accelerated regeneration of microbes accelerates the natural mineralization process, reducing treatment cycle times and virtually eliminating organic contaminant levels.
As best shown in FIG. 2 , in one embodiment, in situ bioreactor tube container 200 has an external slotted pipe structure 220 which has lots of inner bores 220 . Within each inner bore 220 , enough microbial media 210 should be loaded. In one embodiment, there is aeration tubing 230 embedded within the slotted pipe structure 220 . One end of aeration tubing 230 is connected to bioreactor hose 140 and subsequently to bioreactor pump 108 . When the bioreactor pump 108 is on, it supplies air through aeration tubing 230 which tiny air bubbles are created. Air bubbles diffuse from the internal to the external surfaces of bioreactor 200 and ultimately disperse to the surrounding water/liquid medium via numerous inner bores 220 where microbial media 210 are contained. The air bubbles supply both oxygen and nutrients to microbial media 210 and eventually disperse them into the surrounding water/liquid medium.
FIG. 3 is a representative view showing the method of application of the floating bioreactor system 100 of the present invention. As shown in FIG. 3 , floating bioreactor system 100 of the present invention is installed and immersed in the treated liquid medium 310 . The waste 320 is received via inlet pipe 312 and is discharged out through the outlet 314 after treatment. In one embodiment, housing 102 is suspended and floating with the assistance of floats 120 on both side. As best shown in FIG. 3 , when the floating bioreactor system 100 is turned on, bioreactor 200 disperses microbes 360 which are originally contained in its inner bores 220 . The tiny air bubbles 350 generated from aeration tubing 230 will further disperse microbes 360 out of the system while continuously supplying oxygen and nutrients to the microbes 360 . Eventually, the microbes 360 dispersed from bioreactor 200 will establish themselves as the dominant species within the liquid medium 310 being treated.
While at the same time, tiny air bubbles 350 are generated continuously from diffuser grids 130 . The fine air bubbles 350 are more readily absorbed into water per volume of air compared to coarse air bubbles. Consequently, oxygen content is much increased in the treated liquid medium 310 . Moreover, the low head-loss of diffuser grids 130 combined with bioreactor 200 leads to a high efficacy for the microbial population to the liquid medium being treated.
As shown in FIG. 3 , microbial population 360 is dispersed from bioreactor 200 and move vertically away from the bioreactor 200 towards diffuser grids 130 . Air bubbles 350 released not only support the life of the microbes 360 but also help evenly dispense microbes 360 out to the liquid medium for treatment 310 . As best shown in FIG. 3 , the combination of diffuser grids 130 and bioreactor 200 and more importantly their relative orientation in floating bioreactor system 100 of the present invention greatly enhances the efficiency and effectiveness in treating liquid medium 310 .
It will be understood that biosolids and/or sludge handling requirements are eliminated in the present invention. The biosolids are eaten up and consumed by the microbes, thus eliminating the need for sludge and biosolids handling equipment, disposal, etc. In addition, having the microbes on the surface of the water increases the efficiency of oxygen transfer in the floating bioreactor system 100 .
Test Results 1:
Test Laboratory: Robinsons Land Corporation; Analysis No.: WA-10-217 Model: BioCleaner™ 1200 m3 system [16 HP] Test Date Sample—Oct. 18, 2010; Analysis—Oct. 18-23, 2010 Sample Source: STP-Main Mall
Quantitative Water Analysis
DENR Effluent
Standard for
Sample Identification
Influent
Effluent
Inland Water
Method of
(Lab. Sample Nos.)
(S10-WA-506)
(S10-WA-506)
Class C - “NPI”
Analysis
pH, as received
6.41
7.26
6.5-9.0
Glass Electrode
Method
Temperature, ° C.
27.6
28.3
Mercury-Filled
Thermometer
Chemical Oxygen
780.49
25.68
100 maximum
Dichromate Reflux
Demand (COD), mg/L
Method
Biochemical Oxygen
721.26
<1
50 maximum
Azide Modification
Demand (5-days
(Dilution
BOD), mg/L
Technique)
Settleable Solids,
n/a
0.1
0.5 maximum
Volumetric
ml/L
(Imhoff Cone)
Method
Dissolved Oxygen,
n/a
6.58
Azide Modification
mg/L
(Winkler Method)
Total Coliform,
n/a
<2
≦10,000
Multiple Tube
MPN/100 ml
maximum
Fermentation
Technique
As shown in the above Test Result, which the experiment and analysis was carried out by an independent laboratory, after treatment by one of the models of floating bioreactor system 100 of the present invention, the overall quality of waste water improved significantly. Most notable results included the BOD reduction from over 700 mg/L in the influent sample to a mere <1 mg/L in the effluent sample. The value of Total Coliform [ E. coli ] was also reduced to <2 MPN/100 ml. Both values are way lower than the DENR Effluent Standard for Inland Water Class C—“NPI, making the effluent sample Class AA water, better or equivalent to drinking water quality in those respects. The waste water was treated only by floating bioreactor system 100 of the present invention with no chlorination, no filters, no sludge handling and no chemicals, pre or post treatment.
Test Results 2:
Test Laboratory: Robinsons Land Corporation; Analysis No.: WA-11-151 Model: BioCleaner™ 1200 m3 system [16 HP] Test Date Sample—Jul. 5, 2011; Analysis—Jul. 5-21, 2011 Sample Source: STP-Main Mall Methodology: Based on Standard Methods for the Examination of Waste and Wastewater 21 st Edition. APHA, AWWA, WEF
Quantitative Water Analysis
DENR
Effluent
Standard
Sample
for Inland
Identification
Influent
Aeration #1
Aeration #2
Effluent
Water
(Lab. Sample
(S11-WA-
(S11-WA-
(S11-WA-
(S11-WA-
Class C -
Method of
Nos.)
383)
385)
386)
384)
“NPI”
Analysis
pH, as
6.92
8.20
8.19
8.88
6.5-9.0
Glass
received
Electrode
Method
Temperature,
24.2
24.1
24.2
24.1
Mercury-
° C.
Filled
Thermometer
Chemical
1384.62
n/a
n/a
8.60
100
Dichromate
Oxygen
maximum
Reflux
Demand
Method
(COD), mg/L
Biochemical
1098.49
n/a
n/a
<1
50
Azide
Oxygen
maximum
Modification
Demand (5-
(Dilution
days BOD),
Technique)
mg/L
Total
344
2920
2480
7
70
Gravimetric
Suspended
maximum
Method
Solids, mg/L
Total
n/a
2465
2070
n/a
Gravimetric
Volatile
Method
Solids, mg/L
Settleable
15
600
850
<0.1
0.5
Volumetric
Solids, ml/L
maximum
(Imhoff
Cone)
Method
Total
n/a
n/a
n/a
<1.8
≦10,000
Multiple
Coliform,
maximum
Tube
MPN/100 ml
Fermentation
Technique
Test Results 3:
Test Laboratory: Robinsons Land Corporation; Analysis No.: WA-11-258 Model: BioCleaner™ 1200 m3 system [16 HP] Test Date Sample—Nov. 10, 2011; Analysis—Nov. 10-19, 2011 Sample Source: STP-Main Mall Methodology: Based on Standard Methods for the Examination of Waste and Wastewater 21 st Edition. APHA, AWWA, WEF
Quantitative Water Analysis
DENR
Effluent
Standard
Sample
for Inland
Identification
Influent
Aeration #1
Aeration #2
Effluent
Water
(Lab. Sample
(S11-WA-
(S11-WA-
(S11-WA-
(S11-WA-
Class C -
Method of
Nos.)
654)
656)
657)
655)
“NPI”
Analysis
pH, as
5.72
6.91
6.87
6.95
6.5-9.0
Glass
received
Electrode
Method
Temperature,
23.2
22.9
23.3
23.4
Mercury-
° C.
Filled
Thermometer
Chemical
1480
n/a
n/a
18.36
100
Dichromate
Oxygen
maximum
Reflux
Demand
Method
(COD), mg/L
Biochemical
1058
n/a
n/a
<1
50
Azide
Oxygen
maximum
Modification
Demand (5-
(Dilution
days BOD),
Technique)
mg/L
Total
329
2730
2665
2
70
Gravimetric
Suspended
maximum
Method
Solids, mg/L
Total
n/a
2500
2425
n/a
Gravimetric
Volatile
Method
Solids, mg/L
Settleable
2.0
320
320
<0.1
0.5
Volumetric
Solids, ml/L
maximum
(Imhoff
Cone)
Method
Oil and
71.67
n/a
n/a
1.867
5.0
Gravimetric
Grease, mg/L
maximum
Method
(Petroleum
Ether
Extraction)
Total
n/a
n/a
n/a
<1.8
≦10,000
Multiple
Coliform,
maximum
Tube
MPN/100 ml
Fermentation
Technique
The two subsequent experiments show that results show that the overall quality of waste water improved significantly and consistently.
Test Results 4:
Test Laboratory: Chempro Analytical Services Laboratories, Inc.; Ref No.: AR No. 539-c-11 Model: BioCleaner™ 1200 m3 system [16 HP] Test Date Sample—Jun. 9, 2011; Analysis—Jun. 11-17, 2011 Sample Source Wastewater—Effluent (1) Methodology: Based on Standard Methods for the Examination of Waste and Wastewater 20 th Edition. APHA, AWWA, WEF, Washington, D.C. 1998
Analyte(s)
Method
Result(s), mg/L
1. Ammoniacal Nitrogen
Kjeldahl-Titrimetric
1.00
2. Total Nitrogen
Kjeldahl-Titrimetric
1.71
3. Total Phosphate
Colorimetric
0.52
Test Results 5:
Test Laboratory Chempro Analytical Services Laboratories, Inc.; Ref No.: AR No. 597-c-11 Model: BioCleaner™ 1200 m3 system [16 HP] Test Date Sample—Jun. 29, 2011; Analysis—Jul. 2-16, 2011 Sample Source Wastewater (2)/ROB MNL Methodology: Based on Standard Methods for the Examination of Waste and Wastewater 20 th Edition. APHA, AWWA, WEF, Washington, D.C. 1998
Result(s), mg/L
Influent
Effluent
Analyte(s)
Method(s)
LC-1662
LC-1663
1. Total Nitrogen
Kjeldahl-Titrimetric
48.25
3.92
2. Ammoniacal Nitrogen
30.38
2.10
3. Total Phosphate
Colorimetric
11.96
2.82
The results of Test 4 and 5 illustrate that after treatment by one of the models of floating bioreactor system 100 of the present invention, the overall quality of waste water improved significantly in three main areas including the drastic reduction of the level of total nitrogen, ammoniacal nitrogen and total phosphate.
It will be understood based upon the foregoing results of Tests numbers 2-5 that performance of waste reduction and bio-cleaning of water in streams, settling tanks or ponds, aquariums as well as septic systems can be enhanced using the floating and submerged bioreactors of the present invention.
FIG. 4A is a representative view showing one method of adaption of an alternative embodiment, viz. aquarium bioreactor and aerator system 400 . As shown in FIG. 4A , floating bioreactor system 100 of the present invention can be adapted to be used in an aquarium. In one embodiment, aquarium bioreactor and aerator system 400 consists of air pump 414 , air hose 413 and bioreactor and aerator combo 401 . In one embodiment, air pump is a low wattage pump, approximately 2-3 watts, supplying air to in situ bioreactor and aerator combo 401 via air hose 413 . In one embodiment, bioreactor and aerator combo 401 is completely submerged in the water 412 . Preferably, approximately 150 grams by weight of bioreactor and aerator combo 401 should be used for an aquarium of 81 to 160 liters by volume. For smaller tanks with volume below 80 liters, 100 grams by weight of bioreactor and aerator combo 401 should be used.
To sufficiently aerate a 100 gallon tank, air pump 414 should be around 5 watts of power or approximately 0.07 watts of power per gallon of water. In one embodiment, regularly clean filter and the inner wall of the tank to prevent forming of biofilms. The system 400 works best in conjunction with a carbon filter 409 .
The advantages of using aquarium bioreactor and aerator system 400 include no odor, no sedimentation, controlled water pH value, various set microbes for controlling nitrogen cycle, water and energy conservation, fishes that are more resistant to diseases, no need for mechanical filter and no chemicals needed. The present invention reduces the level of ammonia in wastewater, by converting it into nitrates and/or nitrites which can be filtered for removal.
FIG. 4B is a representative side view of bioreactor and aerator combo 401 of aquarium bioreactor and aerator system 400 . FIG. 4C is a representative side partially exposed view of bioreactor and aerator combo 401 of aquarium bioreactor and aerator system 400 . The main purpose of bioreactor and aerator combo 401 is to both generate tiny air bubbles for aeration and disperse microbes to clean up waste in aquariums. As shown in FIG. 4B , the exterior of bioreactor and aerator combo 401 is made of perforated stainless steel plate wherein numerous holes 420 are present. In one embodiment, bioreactor and aerator combo 401 is a canister which is cylindrical in shape with approximate dimensions in the range of four inches by two and a half inches in diameter. As best shown in FIG. 4C , air generated from air pump 414 enters bioreactor and aerator combo 401 via hose 413 subsequently rubber hose 408 inside bioreactor and aerator combo 401 . Air will then reach air diffuser 407 and tiny air bubbles 415 are generated. Air bubbles 415 will then reach surrounding microbial media 406 where appropriate types and amount of microbial is contained. In one embodiment, microbial media 406 contains a combination of lactobacillus , nitrifiers and denitrifiers, and saprotrophic bacteria, i.e., bacteria known as detritivores, also known as detritus feeders or saprophages, that are heterotrophs that obtain nutrients by consuming detritus. Use of combinations of other bacteria, including other types of probiotics, will be apparent to those skilled in the art. Air bubbles 415 will provide oxygen and nutrients for the microbial population to thrive and also disperse them out of bioreactor and aerator combo 401 via holes 420 . The microbes produced by bioreactor and aerator combo 401 will feed on the fish waste and other contaminant in the aquarium making the water 412 clearer and odorless.
In one embodiment, aquarium bioreactor and aerator system 400 helps facilitate the task of maintaining a healthy aquarium. Instead of changing water everyday, it only requires changing an approximate 20 percent of the water, once every 6 months. In general, the aquarium set up is identical to aquariums without aquarium bioreactor and aerator system 400 , including carbon filters 409 for removal of particulate, and regular aeration pump for providing oxygen to fish 410 . Water still needs to be replenished every 2 or 3 days to compensate for evaporative loss.
FIG. 5A is a representative view showing one method of adaption of an alternative embodiment, viz. home septic bioreactor and aerator system 500 . Home septic bioreactor and aerator system 500 provides a method and apparatus for continuous, in-situ microbial seeding at the septic tank 512 . As shown in FIG. 5A , home septic bioreactor and aerator system 500 consists essentially of home septic unit 501 , air pump [not shown] and air hoses 511 . In one embodiment, home septic unit 501 is an immersible container which also serves as a bio-reactor. Home septic unit 501 is immersed in the waste water 530 completely and is secured at the bottom of septic tank 512 at footing 503 by mechanical means. In one embodiment, home septic unit 501 is also attached to cables 510 for support at handle brackets 504 and has an air pump located above the septic tank 512 . In one alternative embodiment, in the case when the septic tank 512 is large enough such as 2 to 3 chambers with a day in each chamber and the waste stream is domestic only, it can be adopted for a myriad of recycle applications. The recycle applications includes having several home septic units 501 immersed into waste water 513 , an additional small sand filter installed at one end, and an additional UV flow tube installed for disinfection.
FIG. 5B is a representative side view of home septic unit 501 of home septic bioreactor and aerator system 500 . FIG. 5C is a representative side partially exposed view of home septic unit 501 of home septic bioreactor and aerator system 500 . Although home septic unit 501 can be in any number of different configurations, in one embodiment, home septic unit 501 is a roughly cylindrical hollow canister having a footing 503 . As shown in FIG. 5B , home septic unit 501 has a cap 505 on top, numerous inlet holes 502 at the bottom and outlet opening 520 near the top half of the structure. In one embodiment, air enters home septic unit 501 via air hose 506 and diffuser hose 509 . As shown in FIG. 5C , home septic unit 501 microbial media 507 in its core that store and produce the microbes. In one embodiment, a diffuser unit 508 is placed at the bottom of home septic unit 501 , which is powered by air pump. Diffuser unit 508 generates tiny air bubbles that provide oxygen and nutrients to microbial that is contained in microbial media 507 and simultaneously creates vacuum that sucks in waste water 530 from inlet holes 503 at the bottom. Waste water 530 travels upward inside home septic unit 501 and is then released at the top via outlet opening 520 . During the journey upward, waste water makes contact with the microbial media 507 in the process and carries with it microbial when it is released back to open water.
By continuous adding a desired microbial population such as a combination of lactobacillus , nitrifiers and denitrifiers, and saprotrophic bacteria directly into waste water 530 to be treated, the present invention 500 allows for demand growth and microbial acclimation based on the waste content within the said environment. The microbial agents generated by the present invention 500 are provided with a continuous supply of oxygen and/or nutrients by diffuser unit 508 , such microbial agents can more effectively mineralize waste within an environment 530 being treated. The present invention 500 can specifically makes the septic tank 512 of houses into a small sewage treatment plant. Over time, the in-situ microbial addition provided by home septic bioreactor and aerator system 500 of the present invention shall make waste water 530 to acceptable discharge level.
FIG. 6A is a representative view showing one method of adaption of an alternative embodiment, viz. aero dynamic mixer bioreactor and aerator system 600 . FIG. 6B is a representative side view of aero dynamic mixer of aero dynamic mixer bioreactor and aerator system 600 . In one embodiment, aero dynamic mixer bioreactor and aerator system 600 essentially is a skirt device which will allow the water to be brought up from the bottom of a lake and/or pond having an approximate depth of 8 meters to 24 meters deep. The main purpose of aero dynamic mixer bioreactor and aerator system 600 is to efficiently spread the good microbes around and also act like a mixing tank which is a very cheap form of cleaning lakes and ponds. In one embodiment, aero dynamic mixer bioreactor and aerator system 600 is an aeration device adapted to be used in outdoor environment such as lakes and ponds. As shown in FIG. 6A , aero dynamic mixer is basically a housing adapted to float within the liquid medium 609 such that the top portion remains above surface of the water/liquid medium 609 . The airlift device has been known for many years and essentially operates by supplying air bubbles into the water at a predetermined depth below the surface. Some of this air is absorbed into the water, which causes the water to become less dense and rise towards the surface. The rising of the water causes circulation 608 , which distributes the aerated water and brings additional water toward the device for aeration and the water is drawn mostly from the bottom of the water body and the sides of aero dynamic mixer bioreactor and aerator system 600 .
Water 609 is aerated in an airlift device by use of a diffuser. When the diffuser is submerged in water 609 , the movement of gas through the device causes bubbles to emerge from the pores and into the water 609 . In one embodiment, the aero dynamic mixer bioreactor and aerator system 600 uses a patented porous rubber houses as a diffuser.
The present invention 600 is comprised of a series of porous diffusers called Aerogrids™ arranged in a way that they are in a straight line. These aeration diffusers are positioned in fiberglass frames that are supported by floaters 603 .
As best shown in FIG. 6B , above the surface are blowers 650 situated to give air to the diffusers. A skirt 606 varying in dimensions, depending on the depth of the medium, wraps around the device 600 in such a way it has openings 607 only at the top and bottom. A small opening 660 is also noticed on one side of the device 600 just below the surface. This will serve as a mouth to water 609 coming out created by the vacuum when the said present invention 600 is turned on. The present invention 600 is capable of drawing water 609 and recirculating it in a very potent manner. Also it is a mobile device that can easily hoist to a boat and move from one location to another.
FIG. 7 is a representative view of the floating aquarium bioreactor and aerator system 700 of the present invention. In one embodiment, floating aquarium bioreactor and aerator system 700 consists of air pump 714 , air hose 713 and bioreactor and aerator combo 701 .
FIG. 8 is a representative view of the floating septic tank bioreactor and aerator system 800 of the present invention. In one embodiment, floating septic tank bioreactor and aerator system 800 consists of air pump 814 , air hose 813 and bioreactor and aerator combo 801 .
Although the inventions herein is to be understood that these are merely illustrative of the principles and applications of the present inventions. Therefore, it is understood that numerous modifications may be made to the illustrative embodiments and that other modifications maybe devised without departing from the scope and functions of the inventions as defined by the claims to be followed.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Although any methods and materials similar or equivalent to those described can be used in the practice or testing of the present invention, the preferred methods and materials are now described. All publications and patent documents referenced in the present invention are incorporated herein by reference.
While the principles of the invention have been made clear in illustrative embodiments, there will be immediately obvious to those skilled in the art many modifications of structure, arrangement, proportions, the elements, materials, and components used in the practice of the invention, and otherwise, which are particularly adapted to specific environments and operative requirements without departing from those principles. The appended claims are intended to cover and embrace any and all such modifications, with the limits only of the true purview, spirit and scope of the invention.
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An aeration and microbial reactor system for use in decontaminating water including a housing adapted to float and/or submerged within the medium such that a top portion thereof remains adjacent a top surface of the contaminated water while the bioreactor containing inoculated carrier media is attached below. Beneficial microbial populations thrive and spread throughout the liquid medium, and consume or fix the contaminant such that the contaminant is removed from the water.
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BACKGROUND OF THE INVENTION
The present invention relates to Internet telephony, and more particularly to an improved end-user interface for Internet-protocol (IP) telephone communication.
Today, Internet telephony is an emerging competitor to conventional telephony as long distance calls are carried over the global Internet at relatively low cost. Additionally, although present Internet telephony systems provide comparably poor quality of service, future improvements will undoubtedly provide signal quality at least on the order of that provided by conventional systems.
Available IP telephones consist primarily of a multimedia personal computer (PC) running a software telephony application which translates end-user sound signals into appropriately formatted digital signals for transfer over a computer network (e.g., the global Internet), and vice versa. Typically, such a multimedia PC includes a sound card with a microphone and a speaker for speech input and output, and accesses the computer network through an appropriate network interface, such as a public switched telephone network (PSTN), a wireless network, or a public or private data network. The software telephony application compresses and decompresses end-user speech signals in order to decrease bandwidth requirements for computer network transmissions. Thus, speech coding and decoding is typically carried out by a central processing unit (CPU) in the multimedia PC. The precise type of speech coding used (e.g., GSM, D-AMPS, etc.) depends upon the bit-rate and speech quality requirements for a given application. Compressed sound signals are transmitted over the computer network using an appropriate UDP/IP network protocol, as is well known in the art. As with speech coding and decoding, the computer network protocol is conventionally administered by the software telephony application running on the multimedia PC.
Despite the above described benefits, the IP telephone of today has several disadvantages as compared to a conventional telephone. For example, common speech coding and decoding algorithms require high performance PCs including relatively fast CPUs. Additionally, the conventional IP-telephone application requires extra sound equipment, such as a sound card and microphone, which is not often included in a standard consumer PC package.
Thus, the conventional IP telephone consists of a relatively high-end PC which is high-priced, power-hungry, and over-sized as compared to a conventional telephone. Additionally, the PC is normally switched off and requires a relatively long and inconvenient boot-up time. Furthermore, even a fully equipped PC does not normally include a comfortable end-user telephone handset, and the relative distance between the PC microphone and PC speaker can cause disturbing echoes for system users. Thus, there is a real need for an improved IP telephone.
SUMMARY OF THE INVENTION
The present invention fulfills the above described and other needs by providing an enhanced radio telephone which can be connected to a PC and used as a significantly improved IP telephone. By way of contrast to an ordinary radio telephone in which a speech coder digital interface is connected exclusively to radio circuitry for wireless communication (e.g., via a cellular radio system), the enhanced radio telephone can transmit and receive digitized and coded speech signals via an alternate external connection as well. Thus, the enhanced radio telephone can selectively operate as either a conventional radio telephone or as an improved IP telephone.
Advantageously, the enhanced radio telephone includes an internal speech coder which is implemented for low power consumption and which allows the enhanced radio telephone to be used with a relatively low-performance PC for effective IP telephony. The enhanced radio telephone thereby provides a low cost IP telephone solution in which speech delay is reduced as compared to conventional IP telephone systems. Additionally, the enhanced radio telephone handset is convenient for speech conversation and reduces the above described echo problems which are commonly associated with conventional IP telephones.
In exemplary embodiments, the enhanced radio handset is connected via a cable to a serial or parallel port of a PC running a streamlined software telephony application. In alternative embodiments, a wireless infrared (IR) or short range radio connection is used for communication between the enhanced radio telephone and the PC. Coded and compressed digital speech signals are passed back and forth between the enhanced radio telephone and the PC, and the PC performs conversions between the coded speech signals and an appropriate computer network protocol. Because the PC need not perform speech coding and decoding, the PC may be implemented, for example, as a low-end desk-top computer, a lap-top/notebook computer, or even a palm-top computer.
Advantageously, a standard PC serial or parallel port connection is sufficient to carry digital speech and control signalling in both directions between the enhanced radio telephone and the PC. According to the invention, IP-telephone control is initiated from either the PC or the enhanced radio telephone. Additionally, the enhanced radio telephone is switched between ordinary wireless (e.g., cellular) operation and IP-telephone operation either manually (e.g., via a pushbutton on the radio handset) or automatically from the PC (e.g., via an option in the telephony application running on the PC). Furthermore, a call can be initiated using either the PC software telephony application or a keypad on the enhanced radio telephone.
In alternative embodiments, the enhanced radio telephone is also used for wireless data communication in order to carry IP speech. In other words, coded speech is passed from the enhanced radio telephone to the PC where it is formatted according to an appropriate UDP/IP network protocol, and the resulting IP speech is passed back to the enhanced radio telephone for transmission to a computer network via a wireless network interface. In such an exemplary embodiment, IP data transfer is conducted using either a separate connection on the enhanced radio telephone or the same connection which is used to carry coded speech and control signalling. Advantageously, a PC serial port is sufficient to carry digital speech, control signalling and IP data.
In brief, the present invention provides an improved IP telephone which is more convenient, economical and efficient as compared to conventional IP telephony systems. These and additional features of the present invention are explained in greater detail hereinafter with reference to the illustrative examples which are shown in the accompanying drawings. Those skilled in the art will appreciate that the described embodiments are provided for purposes of illustration and understanding and that numerous equivalent embodiments are contemplated herein.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a prior art IP telephony system.
FIG. 2 is a block diagram of an IP telephony system constructed in accordance with the teachings of the present invention.
FIGS. 3 and 4 are block diagrams of alternative IP telephony systems constructed in accordance with the teachings of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 depicts a prior art IP telephony system 100. As shown, the conventional system 100 includes a high-performance PC 110 and a network interface 120. The high-performance PC 110 includes a speaker 105, a sound card 125, a microphone 115, a CPU 135, and an input/output port 145. In the figure, an output of the microphone 115 is coupled to an input of the sound card 125, and an output of the sound card 125 is coupled to an input of the speaker 105. An input/output port of the sound card 125 is coupled to a first input/output port of the CPU 135, and a second input/output port of the CPU 135 is coupled to the PC input/output port 145. The PC input/output port 145 is in turn coupled to a first input/output port of the network interface 120, and a second input/output port of the network interface 120 is coupled to a network 130. The network 130 may be, for example, the global Internet or an Intranet operated by a public or private organization. Thus, the term "IP" will be understood to encompass both Internet-protocol and Intranet-protocol systems.
In operation, a near-end user of the PC 110 initiates an IP telephone call, for example by activating a software telephony application on the PC 110. During conversation, the near-end user speaks into the microphone 115, and the audio signal received by the microphone 115 is digitized within the sound card 125. The digitized signal which is output by the sound card 125 is passed to the CPU 135. The CPU 135, which is running the telephony application, compresses and codes the digitized speech using an appropriate speech coding algorithm (e.g., GSM, D-AMPS, etc.) and converts the coded speech, using an appropriate UDP/IP network protocol, into a format which is appropriate for transmission via the network 130. The resulting IP data is transmitted by the CPU 135 via the PC input/output port 145 to the network interface 120, where it is routed to the network 130 and passed on to a far-end user.
Conversely, IP speech signals generated by the far-end user are received from the network 130 at the network interface 120 and passed to the PC 110 via the PC input/output port 145. The CPU 135 receives the IP-formatted far-end data and converts it to corresponding coded far-end speech signals. The coded far-end speech signals are decoded by the CPU 135 using an appropriate algorithm to produce digital sound data which is passed to the sound card 125. The sound card 125 converts the digital far-end sound data into a corresponding analog signal which is directed to the speaker 105 for presentation to the near-end user.
As is well known in the art, the network interface 120 may connect to any one of a number of available systems in order to access the network 130. For example, the network interface 120 may connect to a public switched telephone network (PSTN), a wireless radio system, or a public or private data network as appropriate. Accordingly, the link between the PC 110 and the network interface 120 can utilize any appropriate digital protocol, depending upon the particular type of link used in a given application. When the link is an analog PSTN, the network interface 120 converts digital coded information received from the PC 110 into analog signals suitable for transmission over conventional telephone lines using a conventional modem. When the link is a digital telephone network, the network interface 120 converts digital information received from the PC 110 into a digital protocol associated with the telephone network (e.g., ISDN). When the link is a wireless radio system, the network interface 120 includes a suitable transceiver for modulating and demodulating signals transmitted to, and received from, the network interface 120, respectively. When the link is a public or private data network, the network interface 120 converts digital coded information received from the PC 110 into a format which is appropriate for the public or private network. Advantageously, the network interface 120 can be integrated into the PC 110 or even the CPU 135.
Though the system of FIG. 1 is sufficient for certain applications, it suffers from several significant disadvantages as described above. For instance, advanced speech coding and decoding algorithms, necessary for reduced delay and signal quality, require that the CPU 135 be relatively fast. Additionally, the sound card 125 and the microphone 115 are accessories not typically included in a standard consumer PC package. Furthermore, the relatively complex software telephony application, which must perform both speech coding/decoding and UDP/IP conversion, may be prohibitively expensive and require significant computer memory. Advantageously, the present invention teaches that a radio telephone, ordinarily used exclusively for wireless radio (e.g., cellular) communication, can be enhanced to work in conjunction with a PC-based telephony application so that computationally intensive speech coding and decoding can be performed external to the PC and so that an effective IP telephone can be constructed economically without requiring a high-end computer.
FIG. 2 is a conceptual diagram of an IP telephony system 200 constructed in accordance with the teachings of the present invention. As shown, the improved IP telephony system 200 includes an enhanced wireless telephone 250, a PC 210 and a network interface 120. The enhanced wireless telephone 250 includes a speaker 205 (e.g., an earphone in a wireless handset), a speech decompressor 225, an antenna 255, a radio frequency transceiver 265, a digital interface 275, an external connection 245, a speech compressor 235 and a microphone 215 (e.g., within a mouthpiece in a wireless handset).
As shown, an output of the microphone 215 is coupled to an input of the speech compressor 235, and an output of the speech compressor 235 is coupled to an input of the digital interface 275. Additionally, an output of the digital interface 275 is coupled to an input of the speech decompressor 225, and an output of the speech decompressor 225 is coupled to an input of the speaker 205. The antenna 255 is bi-directionally coupled to the RF transceiver 265 which is in turn bi-directionally coupled to a first input/output port of the digital interface 275. A second input/output port of the digital interface 275 is coupled to the external connection 245, and the external connection 245 is in turn coupled to a first input/output port of the PC 210. A second input/output port of the PC 210 is coupled to a first input/output port of the network interface 120, and a second input/output port of the network interface 120 is coupled to a network 130 such as the global Internet or an Intranet.
In a first, wireless-telephone mode of operation, the digital interface 275 directs output from the speech coder 235 to the radio frequency transceiver 265, and directs output from the radio frequency transceiver 265 to the speech decoder 225, so that the enhanced radio telephone 250 operates as a conventional wireless telephone. In other words, speech signals from the near-end user received at the microphone 215 are compressed and coded by the speech coder 235 and transmitted by the radio frequency transceiver 265 to a wireless (e.g., cellular) system via the antenna 255. Conversely, far-end radio signals received from the wireless system by the radio frequency transceiver 265 are decoded by the speech decoder 225 and presented to the near-end user via the speaker 205.
In a second, IP-telephone mode of operation, the digital interface 275 directs output from the speech coder 235 to the external connection 245, and directs output from the external connection 245 to the speech decoder 225, so that the enhanced radio telephone 250 operates in conjunction with the PC 210 as an improved IP telephone. In other words, coded speech signals are passed from the speech coder 235 to the PC 210 where they are formatted by a software telephony application using an appropriate UDP/IP network protocol. The network-formatted signals are transmitted by the PC 210 to the network 130 via the network interface 120 as described above with reference to FIG. 1. Conversely, network-formatted far-end signals received at the PC 210 via the network interface 120 are converted by the PC telephony application into corresponding coded far-end speech signals. The coded far-end speech signals are passed to the speech decoder 225 where they are decoded and presented to the near-end user via the speaker 205. As above, the network interface 120 may connect to any one of a number of available network links, including a PSTN, a wireless radio system, or a public or private data network. Advantageously, the network interface 120 can be integrated within the PC 210.
The speech coder 235 and the speech decoder 225, respectively, code and decode speech during IP-telephone operation using the same algorithms (e.g., GSM, D-AMPS, etc.) used during radio-telephone operation. Advantageously, the speech coder 235 and the speech decoder 225 are constructed in accordance with the radio telephone art to operate at high speed using relatively little power. Because the burden of speech coding and decoding is removed from the telephony application running on the PC 210, the telephony application can be streamlined, and the CPU within the PC 210 need not be nearly as fast as that of the PC 110 of the system of FIG. 1. Additionally, the PC 210 need not include a sound card, a microphone, or a speaker. As a result, the PC 210 can be implemented using a relatively inexpensive, relatively low-performance computer. Additionally, the enhanced radio telephone 250 provides a convenient and comfortable handset for the near-end user and significantly reduces the echo problem associated with conventional IP telephones. For example, because the near-end user holds the handset to his or her ear, the echo path between the microphone and the speaker is largely blocked. Furthermore, the enhanced radio telephone 250 can provide echo canceling circuitry as is well known in the radio telephone art.
In the embodiment of FIG. 2, coupling between the external connection 245 and the PC 210 is implemented using a standard serial or parallel PC cable connection. Alternatively, the connection can be established using well known IR or shortwave radio techniques. Coded speech and control information is exchanged between the enhanced radio telephone 250 and the PC 210 using handshaking techniques which are well known in the art. The enhanced radio telephone 250 and the PC 210 are programmed so that IP-telephone operation can be controlled from either the PC 210 or the enhanced radio telephone 250. Switching between IP-telephone operation and wireless-telephone operation can be initiated manually using a keypad on the enhanced radio telephone 250 or automatically via the telephony application running on the PC 210. Additionally, a user of the enhanced radio telephone 250 can initiate a call using either the enhanced radio telephone keypad or the telephony application on the PC. Thus, the embodiment of FIG. 2 provides an improved IP telephone which is more convenient, economical and efficient than conventional IP telephones.
FIG. 3 is a conceptual diagram of an alternative IP telephony system 300 constructed in accordance with the teachings of the present invention. As shown, the IP telephony system 300 includes an enhanced wireless telephone 350, a PC 310 and a network interface 120. The enhanced wireless telephone 350 includes a speaker 205, a speech decompressor 225, an antenna 255, a radio frequency transceiver 265, a digital interface 275, first and second external connections 345, 346, a speech compressor 235 and a microphone 215.
As shown, an output of the microphone 215 is coupled to an input of the speech compressor 235, and an output of the speech compressor 235 is coupled to an input of the digital interface 275. Additionally, an output of the digital interface 275 is coupled to an input of the speech decompressor 225, and an output of the speech decompressor 225 is coupled to an input of the speaker 205. The antenna 255 is bi-directionally coupled to the RF transceiver 265 which is in turn bi-directionally coupled to a first input/output port of the digital interface 275. A second input/output port of the digital interface 275 is coupled to each of the external connections 345, 346. The first external connection 345 is coupled to an input/output port of the PC 310, and the second external connection 346 is coupled to a first input/output port of the network interface 120. A second input/output port of the network interface 120 is coupled to a network 130 such as the global Internet or an Intranet.
In general, operation of the exemplary embodiment of FIG. 3 is similar to that of FIG. 2. For example, in a first, wireless-telephone mode of operation, the digital interface 275 directs output from the speech coder 235 to the radio frequency transceiver 265, and directs output from the radio frequency transceiver 265 to the speech decoder 225, so that the enhanced radio telephone 250 operates as a conventional wireless telephone. However, during an IP-telephone mode of operation, the PC 310 is used to convert between coded speech data and network-formatted data, and the enhanced radio telephone 350 is used to exchange network-formatted data with the network 130 via the network interface 120.
During IP-telephone operation, coded speech signals are passed from the speech coder 235 to the PC 310 where they are formatted by a software telephony application using an appropriate UDP/IP network protocol. Thereafter, the network-formatted signals are directed back from the PC 310 to the enhanced radio telephone 350 and transmitted to the network 130 via the network interface 120. Conversely, network-formatted far-end signals received at the enhanced radio telephone 350 via the network interface 120 are passed to the PC 310 and converted by the telephony application into corresponding coded far-end speech signals. The coded far-end speech signals are passed back to the enhanced radio telephone 350 and then to the speech decoder 225 where they are decoded and presented to the near-end user via the speaker 205.
As described above with respect to FIGS. 1 and 2, the network interface 120 may connect to any one of a number of available network links, including a PSTN, a wireless radio system, or a public or private data network. Advantageously, the network interface 120 may be integrated within the enhanced radio telephone 350. When the link is a PSTN, the network interface 120 may comprise a modem or an ISDN line. When the link is a public or private data network, the network interface 120 comprises an appropriate digital connection (e.g., an Ethernet connection). When the link is a wireless radio system, the network interface 120 comprises a suitable transceiver for modulating and demodulating network-formatted signals as necessary. Advantageously, the RF transceiver 265 can be adapted to provide appropriate wireless communication during both the wireless-telephone mode of operation and the IP-telephone mode of operation. In other words, the operating frequencies of the RF transceiver 265 can be tuned as necessary to communicate with different systems.
The embodiment of FIG. 3 provides advantages similar to those described above with respect to the embodiment of FIG. 2. Additionally, because the task of communicating with the network 130 is shifted to the enhanced radio telephone 350, the PC 310 (and the telephony application running on the PC 310) can be streamlined still further. Thus, like the embodiment of FIG. 2, the exemplary embodiment of FIG. 3 provides an improved IP telephone which is more convenient, economical and efficient than conventional IP telephones.
FIG. 4 is a conceptual diagram of another alternative IP telephony system 400 constructed in accordance with the teachings of the present invention. As shown, the IP telephony system 400 includes an enhanced wireless telephone 450 and a network interface 120. The enhanced wireless telephone 450 includes a speaker 205, a speech decompressor 225, an antenna 255, a radio frequency transceiver 265, a digital interface 275, a network converter 410, an external connection 445, a speech compressor 235 and a microphone 215.
As shown, an output of the microphone 215 is coupled to an input of the speech compressor 235, and an output of the speech compressor 235 is coupled to an input of the digital interface 275. Additionally, an output of the digital interface 275 is coupled to an input of the speech decompressor 225, and an output of the speech decompressor 225 is coupled to an input of the speaker 205. The antenna 255 is bi-directionally coupled to the RF transceiver 265 which is in turn bi-directionally coupled to a first input/output port of the digital interface 275. A second input/output port of the digital interface 275 is coupled to a first input/output port of the network converter 410, and a second input/output port of the network converter 410 is coupled to the external connection 445. Additionally, the external connection 445 is coupled to a first input/output port of the network interface 120, and a second input/output port of the network interface 120 is coupled to a network 130 such as the global Internet or an Intranet.
In general, operation of the exemplary embodiment of FIG. 4 is similar to operation of the embodiments of FIGS. 2 and 3. For example, in a first, wireless-telephone mode of operation, the digital interface 275 directs output from the speech coder 235 to the radio frequency transceiver 265, and directs output from the radio frequency transceiver 265 to the speech decoder 225, so that the enhanced radio telephone 450 operates as a conventional wireless telephone. However, during an IP-telephone mode of operation, the internal network converter 410 converts between coded speech data and network-formatted data, and therefore an external PC is not necessary.
During IP-telephone operation, coded speech signals are passed from the speech coder 235 to the network converter 410 where they are formatted using an appropriate UDP/IP network protocol. Thereafter, the network-formatted signals are directed to the network 130 via the network interface 120. Conversely, network-formatted far-end signals received at the enhanced radio telephone 350 via the network interface 120 are converted by network converter 410 into corresponding coded far-end speech signals. The coded far-end speech signals are passed through the digital interface 275 to the speech decoder 225 where they are decoded and presented to the near-end user via the speaker 205.
As described above with respect to FIGS. 1-3, the network interface 120 may connect to any one of a number of available network links, including a PSTN, a wireless radio system, or a public or private data network. Advantageously, the network interface 120 may be integrated within the enhanced radio telephone 350. When the link is a PSTN, the network interface 120 may comprise a modem or an ISDN line. When the link is a public or private data network, the network interface 120 comprises an appropriate digital connection (e.g., an Ethernet connection). When the link is a wireless radio system, the network interface 120 comprises a suitable transceiver for modulating and demodulating network-formatted signals as necessary. As above, the RF transceiver 265 can be adapted to provide appropriate wireless communication during both the wireless-telephone mode of operation and the IP-telephone mode of operation. In other words, the operating frequencies of the RF transceiver 265 can be tuned as necessary to communicate with different systems.
The embodiment of FIG. 4 provides advantages similar to those described above with respect to the embodiments of FIGS. 2 and 3. Additionally, because the task of converting between IP signals and coded speech signals is integrated into the enhanced radio telephone 450, the need for an external PC is eliminated. Thus, like the embodiments of FIGS. 2 and 3, the exemplary embodiment of FIG. 4 provides an improved IP telephone which is more convenient, economical and efficient than conventional IP telephones. In practice, any one of the embodiments of FIGS. 2-4 can be utilized to advantage, depending upon the cost and performance requirements of a given application.
Those skilled in the art will appreciate that the present invention is not limited to the specific exemplary embodiments which have been described herein for purposes of illustration. The scope of the invention, therefore, is defined by the claims which are appended hereto, rather than the foregoing description, and all equivalents which are consistent with the meaning of the claims are intended to be embraced therein.
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An enhanced radio telephone providing both wireless communication and Internet-protocol (IP) telephone communication. In addition to transmitting and receiving digitized and coded speech signals in a wireless fashion using a radio transceiver, the enhanced radio telephone can also exchange coded speech data with a computer which is coupled to a communication network. Thus, the enhanced radio telephone can selectively operate as either a conventional radio telephone or as an improved IP telephone. The enhanced radio telephone includes an internal speech coder which is implemented for low power consumption and which allows the enhanced radio telephone to be used with a relatively low-cost computer for effective and economic IP telephony.
In exemplary embodiments, an enhanced radio handset is connected to an input/output port of a personal computer running a software telephony application. Coded and compressed digital speech signals are passed back and forth between the enhanced radio telephone and the computer, and the computer performs conversions between the coded speech signals and an appropriate network protocol. Because the computer does not perform speech coding and decoding internally, the computer functionality may be implemented, for example, using an inexpensive notebook or palm-top computer. Advantageously, a user may initiate telephone calls from either the enhanced radio telephone or the telephony application running on the computer.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present disclosure relates to a method for monitoring the operation of underwater-located equipment and monitoring apparatus for underwater-located equipment.
[0003] 2. Description of Related Art
[0004] Underwater installations, for example subsea hydrocarbon production wells, typically include vital components which, if they were to fail, could cause significant problems. It is therefore important to monitor the operation of such components, which may not be straightforward for such remotely-located components. For example, an essential method of controlling the flow of production fluid from a subsea wellhead is by utilising at least one valve production control valve, fitted on a subsea tree, which can be opened or shut as required. Generally these valves are hydraulically operated. A known, conventional method of measuring the position of such a valve is by using at least one pressure transducer which is connected to at least one of the hydraulic supply or return line of the valve. The or each transducer is usually fitted at the manifold of the installation, and electrical output signals from the transducer are passed to control means at the surface via an umbilical cable. The actual measured pressure provides an indication of the state of opening or closing of the valve, thus enabling it to be controlled from the surface. Information provided by the pressure transducer also enables a limited assessment to be made of the condition and performance of the valve but this may be affected by various factors, for example fluid temperatures, fluid cavitation and other fluid flow effects and leakages.
[0005] Recently, efforts have been made to improve both the range and reliability of information available through the assessment of signals produced from subsea sensors, an example being the condition monitoring system known from co-pending patent application GB 0916421.1.
[0006] It has now been found that the use of known pressure transducer monitoring arrangements provide insufficient information to enable a full analysis of equipment, such as a valve as described above, using condition monitoring techniques.
BRIEF SUMMARY OF THE INVENTION
[0007] In view of the above, there is provided a method for monitoring the operation of underwater-located equipment, comprising: providing a sensor, the sensor comprising at least one of an acoustic sensor and an accelerometer; locating the sensor proximate the equipment to enable detection by the sensor of acoustic and/or acceleration components produced by the operation of the equipment; and producing electrical output signals in dependence on the detected components.
[0008] According to another aspect, there is provided a monitoring apparatus for underwater-located equipment comprising a sensor for monitoring the operation of the equipment, the sensor comprising at least one of an acoustic sensor and an accelerometer and being operable to output electrical signals in dependence on acoustic and/or acceleration components produced by the operation of the equipment.
[0009] Further aspects, advantages and features of the method or apparatus for monitoring underwater-located equipment are apparent from the dependent claims, the description and the accompanying drawings.
[0010] Advantages including the following may result from implementation of the method or apparatus for monitoring underwater-located equipment: early identification of potential failures; opportunity to change out deteriorating equipment during normal operations; reduction in unplanned operations; reduced repair costs and downtime; extended equipment life; better control of spare parts, thus reducing costs; reduction in lost production; the possibility of providing valuable information for preventative maintenance systems; and the enabling of optimisation of fluid flow conditions.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0011] A full and enabling disclosure including the best mode thereof, to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, including reference to the accompanying figures wherein:
[0012] FIG. 1 schematically shows an embodiment of the present invention using an acoustic sensor; and
[0013] FIG. 2 schematically shows a second embodiment of the present invention using an accelerometer.
DETAILED DESCRIPTION OF THE INVENTION
[0014] Reference will now be made in detail to the various embodiments, one or more examples of which are illustrated in each figure. Each example is provided by way of explanation and is not meant as a limitation. For example, features illustrated or described as part of one embodiment can be used on or in conjunction with other embodiments to yield yet further embodiments. It is intended that the present disclosure includes such modifications and variations.
[0015] A first embodiment of the present invention, using an acoustic sensor, is schematically shown in FIG. 1 . Here the equipment being monitored is a production control valve located on a subsea tree of a hydrocarbon production well. An acoustic sensor, in this example a hydrophone 1 , is fitted to a subsea production control valve 2 , which is mounted on a subsea tree 3 . The valve 2 is controlled by operating signals received from a subsea control module (SCM) 4 via line 5 . The valve 2 may be hydraulically or electrically operated.
[0016] The hydrophone is electrically connected to a subsea electronics module (SEM) 6 , housed in the SCM 4 , via a cable 7 . The SCM 4 and SEM 6 are in communication with a well head control system 8 , which is provided at a surface location (referred to as “topside” in the art), for example onshore, or at a vessel or platform, via an umbilical cable 9 , as is known in the art.
[0017] The hydrophone 1 is adapted to capture the acoustic signature of the production control valve 2 and convert the data to an associated electrical signal. The term “acoustic signature” as used herein refers to the frequency response as measured over a period of time associated with the operation of the valve. The electrical signal is passed via the cable 7 to SEM 6 . The SEM 6 in turn transfers this via umbilical cable 9 to the wellhead control system 8 for data analysis.
[0018] The data analysis performed within the wellhead control system utilises pattern recognition algorithms to compare the received data against a database which contains historical data. Typically the historical data relate to valve position as well as fault condition acoustic signatures. By suitable comparison, the position of the valve 2 may be determined. In addition, the processing may recognise whether there is abnormal behaviour, i.e. a fault, of the valve. The processing is performed in conjunction with feedback from the other control system information, for example monitoring information relating to other equipment or components at the tree.
[0019] FIG. 2 shows a second embodiment of the present invention, which has much similarity to the first embodiment and like components are denoted with the same reference numerals. However, in this embodiment the sensor used to monitor the valve operation is an accelerometer 10 , which is connected to SEM 6 via a cable 11 . The accelerometer 10 can capture continuous movement signals, caused by physical actuation of valve 2 . The acceleration data captured by accelerometer 10 may be compared with known acceleration signatures of valve states and also be used to determine the opening and closing state of the valve.
[0020] In this way, an acoustic sensor or accelerometer is employed, which may be mounted on an underwater host facility, for example a subsea well tree, and capable of continuously capturing acoustic/acceleration signals and the associated acoustic/acceleration frequency spectrum. These may then be relayed to a surface location, where the data can be compared with known acoustic/acceleration signatures for the relevant equipment, e.g. various valve states, and used to determine the state of operation of the equipment, e.g. opening and closing of the valve.
[0021] The condition, amount of degradation and performance of the equipment can be measured by using pattern recognition techniques, to predict condition and deduce the causes of faults and performance loss. This is achieved by comparing signatures with historical data and modelling results of various equipment conditions. The information can be used to determine the optimum time to carry out maintenance and this in turn will reduce down time for carrying out unexpected repairs. This data can be used in conjunction with information on the control system operations to detect and monitor subsea equipment condition and performance.
[0022] The present technique enables monitoring of subsea hardware and in the case of fluid flow for example could be used to confirm valve and choke movement, monitor changes in operating profile, detect cavitations in fluid flow and other flow regimes, detect fluid leakage and monitor the flow in fluid pipelines. The technique has general application to subsea equipment generating a measurable frequency spectrum/acceleration.
[0023] Several pieces of equipment, for example valves and chokes, may be involved in controlling the fluid flow from a well and further devices such as high integrity pipeline protection valves, may be monitored to ensure operational safety. Each of these could be fitted with an acoustic sensor/accelerometer, or alternatively a single acoustic sensor/accelerometer may be used to monitor multiple items of equipment (e.g. valves/chokes).
[0024] The above-described embodiments are exemplary only, and other possibilities and alternatives within the scope of the present invention will be apparent to those skilled in the art. For example, although the examples described above use only a single sensor, it is also possible to use more than one, for example both an accelerometer and an acoustic sensor may be used, or indeed a plurality of sensors of either type and in any combination. The data from the individual sensors may be collated by the wellhead control system, and used to improve accuracy or reliability of monitoring. Furthermore, the use of additional sensors provides a level of redundancy, such that monitoring may still be available in the event that one sensor fails.
[0025] The monitoring system could be used to monitor any item of equipment which produces in use an acoustic output or movement.
[0026] The or each acoustic sensor/accelerometer could be located on the tree, rather than on a specific item of equipment. This would enable output from a plurality of items to be monitored.
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A method for monitoring the operation of underwater-located equipment is provided. The method comprises: providing a sensor, the sensor comprising at least one of an acoustic sensor and an accelerometer, locating the sensor proximate the equipment to enable detection by the sensor of acoustic and/or acceleration components produced by the operation of the equipment, and producing electrical output signals in dependence on the detected components.
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BACKGROUND OF THE INVENTION
The present invention relates to a protection structure for a thermal conducting medium of a heat dissipation device, and more particular, to a protection structure installed on the heat dissipation device at the position on which the thermal conducting medium is coated.
The commonly seen heat dissipation device such as the aluminum extrusion type heat dissipation device is attached on a central processing unit (CPU) to aid in heat dissipation when the central processing unit is operating. Thereby, the central processing can operate under a tolerable working temperature. Before the heat dissipation device is attached on the central processing unit, an adequate amount of thermal conducting medium such as thermal conductive paste is coated on the heat dissipation device, such that a close contact between the heat dissipation device and the central processing unit can be ensured.
The thermal conducting medium is typically in the form of a paste that easily cause adherence of dust and contamination. In case the heat dissipation device is dropped or in contact with external object before being attached to the central processing unit, the thermal conducting effect will be greatly degraded by the dust or contamination. In addition, the amount of the thermal conducting medium applied to the heat dissipation device is also a crucial parameter that affects the heat dissipation performance. Therefore, if the thermal conducting medium is coated by the end user who does not own a proper judgment of the amount, the heat dissipation performance may be degraded by improper amount of thermal conducting medium. If the thermal conducting medium is coated before the final assembly, dust and contamination is easily attached to the heat dissipation device, which again, causes degradation of heat dissipation.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a protection structure for a thermal conducting medium of a heat dissipation device. The protection structure covers the thermal conducting medium to prevent dust and contamination adhered thereto.
The present invention further provides a protection structure for a thermal conducting medium of a heat dissipation device which also covers the heat dissipation device to provide a complete package of the heat dissipation device.
The protection structure provided by the present invention comprises a bottom surface to cover the thermal conducting medium, a side wall extending along and projecting from a periphery of the bottom surface to form a space for receiving the thermal conducting medium and a portion of the heat dissipation device, and a support structure protruding from the bottom surface to avoid a direct contact between the thermal conducting medium and the bottom surface. The support structure includes at least one pair of semi-spherical bumps, one pair of parallel ribs, or one pair of elongate ridges extending across the bottom surface. In the embodiment when the support structure includes a pair of elongate ridges extending across the bottom surface, the space formed by the sidewall is divided into a central space for receiving the thermal conducting medium and two spaces at two opposing sides of the central space. Preferably, the dimension of the central space is larger than the surface area of the thermal conducting medium.
The protection structure may further comprises a plurality of friction fit structure protruding from the side wall, such that the heat dissipation device inserted in the space can be secured to the protection structure. The friction fit structure includes a plurality of ribs. Preferably, the top edge of the side wall further includes a flange. The heat dissipation device includes a substrate, a plurality of fins projecting from a first surface of the substrate, and the thermal conducting medium attached to a second surface of the substrate. The bottom surface is conformal to the substrate. The side wall has a height lower than the height of the fins. In other embodiment, the side wall is level with the tips of the fins. The protection structure further comprises a lid to seal the heat dissipation device within the protection structure.
These and other objectives of the present invention will become obvious to those of ordinary skill in the art after reading the following detailed description of preferred embodiments.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
These, as well as other features of the present invention, will become apparent upon reference to the drawings wherein:
FIG. 1 shows a perspective view of a protection structure according to a first embodiment of the present invention;
FIG. 2 shows an exploded view of the protection structure applied to a heat dissipation device;
FIG. 3 shows a perspective view of the assembly of the protection structure and the heat dissipation device;
FIG. 4 shows a cross sectional view of the assembly;
FIG. 5 shows an exploded view of a protection structure applied to a heat dissipation device according to a second embodiment of the present invention;
FIG. 6 shows a cross sectional view of the assembly as shown in FIG. 5 ;
FIG. 7 shows a cross sectional view of an assembly of a protection structure and a heat dissipation device according to a third embodiment of the present invention; and
FIG. 8 shows a perspective view of a protection device according to a fourth embodiment of the present invention; and
FIG. 9 shows a cross sectional view of the protection device as shown in FIG. 8 applied to a heat dissipation device.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings wherein the showings are for purpose of illustrating preferred embodiments of the present invention only, and not for purposes of limiting the same.
A perspective view of a first embodiment of the protection structure is illustrated as FIG. 1 , an exploded view the protection structure applied to a heat dissipation device is shown in FIG. 2 , and FIG. 3 illustrates the perspective view of the assembly of the protection structure and the heat dissipation device. FIG. 4 shows the cross sectional view of the assembly. As shown, a heat dissipation device 2 is coated with a thermal conducting medium 20 such as a thermal conductive paste, and the protection structure 1 is used to cover and protect the thermal conducting medium 20 from being exposed to dust or contamination.
As shown in FIGS. 1 to 4 , the protection structure 1 includes a bottom surface 10 , a continuous side wall 11 extending substantially perpendicularly from the periphery of the bottom surface 10 , and at least two contact portions 12 protruding inwardly from the bottom surface 10 .
When the protection structure 1 is applied to the heat dissipation device 2 , the bottom surface 10 is on top of the thermal conducting medium 20 . As shown, the heat dissipation device 2 includes a heat sink formed by aluminum extrusion, for example. The heat sink includes a substrate 21 and a plurality of fins 22 formed on a top surface of the substrate 21 . In this embodiment, the thermal conducting medium 20 is coated on the bottom surface of the substrate 21 . Preferably, the contact portions 12 are spaced from each other to form a space larger than the surface area of the thermal conducting medium 20 .
The continuous side wall 11 includes a plurality of side surfaces 110 . Depending on the shape of the bottom surface 10 , the arrangement of the side surfaces 110 may be altered. In the embodiment as shown in FIGS. 1 to 4 , the bottom surface 10 has a rectangular shape, such that four side surfaces 110 construct the continuous side wall 11 in the example. When the bottom surface 10 is circular, only one side surface 110 is required. The bottom surface 10 and the side wall 11 forms a space 13 allowing a portion of the substrate 21 to be inserted therein. Preferably, the bottom surface 10 is conformal to the substrate 21 .
When the substrate 21 is partially inserted in the space 13 of the protection structure 1 , the contact portions 12 prevent the bottom surface 10 from contacting with and pressurizing against the thermal conducting medium 20 . In the example as shown in FIG. 4 , the contact portions 12 include four semi-spherical protrusions. By the contact portions 12 , the substrate 21 is distant from the bottom surface 10 by a space 130 when the substrate 21 is inserted in the protection structure 1 ; and therefore, the thermal conducting medium 20 will not be damaged by the direct contact with the bottom surface 10 .
In addition, the top edge of the continuous side wall 11 includes a flange 111 extend outwardly from the space 130 . The flange 111 increases the structure strength and prevents the protection structure 1 from distortion. Further, it provides the convenience of inserting the substrate 21 into the space 130 .
FIGS. 5 and 6 shows a modification of the first embodiment of the protection structure 10 . In this embodiment, the side wall 11 extends longer to cover the full height of the heat dissipation device 2 , and the contact portions 12 includes a pair of protruding ridges formed the bottom surface 10 . In addition to the contact portions 12 , a pair of ridges protrudes inwardly from the side surfaces 110 to serve as fitting elements 112 . Thereby, the protection structure 10 can secure the heat dissipation device 1 therein by friction fit. As shown, the tips of the fins 22 are level with the top edge of the side wall 11 , and the protection structure 1 encloses the heat dissipation device 2 therein to be advantageous to package process.
FIG. 7 shows a third embodiment of the protection structure 1 , which is a modification of the second embodiment. As shown, a lid 14 is added to cover the open end of the protection structure 1 , such that the heat dissipation device 2 is sealed in the protection structure 1 . The protection structure 1 thus serves as a package of the heat dissipation device 2 as well.
FIG. 8 illustrates the perspective view of a protection structure in a fourth embodiment of the present invention, and FIG. 9 shows a cross sectional view of the assembly of the protection structure and a heat dissipation device. As shown, the heat dissipation device 2 ′ includes a substrate 21 ′ and a stack of fins 22 ′ attached on the substrate 21 ′. The substrate 21 ′ further includes a plurality of resilient fastening members 23 penetrating through the substrate 21 ′.
The protection structure 1 includes a bottom surface 10 , a pair of side surfaces 110 , and a pair of elongate ridges 114 protruding from the bottom surface 10 . As shown, the elongate ridges 114 extending from one edge to the other of the bottom surface 10 and are parallel to the side surfaces 110 . Preferably, the height of the side surfaces 110 is higher than that of the ridges 12 , and the space 13 formed between the side surfaces 110 is slightly larger than that of the substrate 21 ′. Therefore, the heat dissipation device 2 ′ can be partially disposed in the space 13 . The lower portion of the space 13 is divided into three parts, including the central portion 130 between the ridges 12 and the side portions 131 between the ridges 12 and the side surfaces 110 . When the heat dissipation device 2 ′ is inserted in the space 13 , the protruding ridges 12 serves as supporting arms of the substrate 21 ′. Each of the protruding ridges 12 includes a side wall 114 facing the side surface 110 , a side wall 113 facing the side wall 113 of the other ridge 12 , and a top wall 112 . The top wall 112 is in direct contact with the substrate 21 ′ when the heat dissipation device 1 is inserted in the space 13 . Further, the distance between the ridges 12 , that is, the dimension of the space 130 is preferably larger than the dimension (width or length) of the thermal conducting medium 20 , such that the thermal conducting medium 20 , while being covered and protected by the protection structure 1 , is not in contact with any structure or element. The spaces 131 allow the fastening members 23 to insert therein.
This disclosure provides exemplary embodiments of the present invention. The scope of this disclosure is not limited by these exemplary embodiments. Numerous variations, whether explicitly provided for by the specification or implied by the specification, such as variations in shape, structure, dimension, type of material or manufacturing process may be implemented by one of skill in the art in view of this disclosure.
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A protection structure for a thermal conducting medium of a heat dissipation structure installed on the heat dissipation device at the position on which the thermal conducting medium is coated. The protection structure has a bottom surface to cover the thermal conducting medium, a side wall extending along and projecting from a periphery of the bottom surface to form a space for receiving the thermal conducting medium and a portion of the heat dissipation device, and a support structure protruding from the bottom surface to avoid a direct contact between the thermal conducting medium and the bottom surface.
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CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority to International Patent Application No. PCT/US2012/063790, filed Nov. 7, 2012 and entitled “METHOD OF INCREASING THE PERFORMANCE OF CATIONIC FABRIC SOFTENERS” which claims priority to U.S. Provisional Application 61/558,551 filed Nov. 11, 2011 and entitled “METHOD OF INCREASING THE PERFORMANCE OF CATIONIC FABRIC SOFTENERS BY ADDITION OF QUATERNARY (METH)ACRYLIC POLYMERS”, which is incorporated herein.
FIELD OF THE INVENTION
The present invention relates to fabric softeners comprising cationic thickeners and in particular to a method of increasing the fabric softening efficacy of a fabric softener by incorporating a quaternary (meth)acrylic polymer. The present invention also relates to the use of a quaternary (meth)acrylic polymer as a fabric softening active.
BACKGROUND OF THE INVENTION
Liquid fabric treatment compositions suitable for fabric softening and static control during the laundry process are well known in the art and widespread in commercial success. These liquid fabric treatment compositions typically contain quaternary ammonium cationic surfactants (commonly referred to as quats, or quaternary fabric softeners) that provide fabric-softening and anti-static benefit during the laundry rinse cycle.
Viscosities are important in formulating both concentrated/premium liquid fabric softeners having high levels of quaternary fabric softener and dilute/discount products having low levels of actives. For concentrated products, electrolytes such as calcium chloride have been used to control viscosity, however addition of up to about 2000 ppm CaCl 2 does nothing more than allow a few more percent active quaternary to be added to the formula. This is exemplified in U.S. Pat. No. 3,681,241 (Rudy at al.) wherein formulations comprising only up to about 12% active quaternary are possible. This is also exemplified in U.S. Pat. No. 4,772,404 (Fox et al.) where formulas having up to 15% quaternary blend (Varisoft 222LM and Adogen 442 in a critical ratio) are stabilized with triethanolammonium citrate and 0.09% calcium chloride. Another approach has been to combine fabric “softener” and fabric “substantive” agents. For example U.S. Pat. No. 4,155,855 (Goffinet, et al.), U.S. Pat. No. 4,157,307 (Jaeger et al.) and U.S. Pat. No. 4,855,072 (Trinh et al), describe combination of fabric softening and fabric substantive agents, wherein the fabric substantive agent is a quaternary imidazolinium salt. However, even though the compositions may contain as much as 25-50% of a blend of these two quaternary materials, only the softening agent (a conventional quaternary) appears to confer the softening and antistatic benefit to the fabric.
Other methods to stabilize concentrated fabric softener compositions having high levels of quaternary actives utilize additional surfactants, solvents or polymers. For example, as described in U.S. Pat. No. 4,326,965 (Lips et al.), stable formulas with up to 40% active quaternary are possible when incorporating 4-25% polymer having MW greater than 400. U.S. Pat. No. 4,556,502 (Blackmore et al.) describes concentrated fabric softener formulations with up to 40% active quaternary if stabilized with greater than 0.5% amphoteric surfactants and 5-30% alkanol solvent. Lastly, U.S. Pat. No. 4,233,164 (Davis) describes stabilization of 2-11% quaternary active formulations through the use of 1-5% nonionic surfactant.
Cost-reduced liquid fabric softeners may comprise lower levels of quaternary surfactant, for example less than about 10 wt. % actives and even less than about 5 wt. % actives. However, these liquids often lack any viscosity and may appear “cheap” to the consumer. Thickeners have been used to give a more “premium” appearance to dilute liquid fabric softeners having low quaternary surfactant active levels. However, some thickeners such as cationic gums and starches are not expected to change the performance of the product, but instead only expected to add cost. Examples of the use of cationic thickeners in fabric softeners is known and may be found in U.S. Pat. No. 6,949,500 (Salesses, et al.) and U.S. Pat. No. 6,514,931 (Grainger, et al.) and U.S. Patent Application Publication 2006/0252668 (Frankenbach, et al.).
Accordingly, additional development of liquid fabric softeners is warranted, ideally with research into thickeners that may bring other benefits to liquid fabric softeners other than viscosity control.
SUMMARY OF THE INVENTION
It has now been surprisingly found that parity fabric softening performance is possible in a cost-reduced fabric softener by the addition of a cationic rheology modifier having quaternary structure. The cationic thickener provides an unexpected fabric softening effect and is much less expensive than quaternary surfactant compounds such as the ester quats typically used as the active softener in liquid fabric softeners.
In a preferred embodiment of the present invention, less than 0.5 wt. % actives cationic polymer or co-polymer derived from at least one quaternized (meth)acrylic monomer boosts the softening performance of a low-actives quat-based fabric softener.
In another preferred embodiment of the present invention, as little as less than 0.5 wt. % actives poly[{2-(methacryloyloxy)ethyl}trimethylammonium chloride] homopolymer boosts the performance of a liquid fabric softener having only 8.0 wt. % actives ester quat softener back up to the softening performance of a liquid composition having 10 wt. % actives quaternary softener and no cationic thickener.
In another preferred embodiment of the present invention, as little as less than 0.5 wt. % actives poly[{3-(methacryloyloxy)propyl}trimethylammonium chloride] homopolymer boosts the performance of a liquid fabric softener having only 8.0 wt. % actives ester quat softener back up to the softening performance of a liquid composition having 10 wt. % actives quaternary softener and no cationic thickener.
In yet another preferred embodiment of the present invention, various quaternized (meth)acrylic polymers, including acylates, methacrylates, acrylamides, and methacrylamides, having quaternized appendages, are used as fabric softening actives.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a 3D surface plot of fabric softening against cationic thickener and esterquat.
FIG. 2 is also a 3D surface plot of fabric softening against cationic thickener and esterquat.
DETAILED DESCRIPTION OF THE INVENTION
The following description is of exemplary embodiments only and is not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. Various changes to the described embodiments may be made in the function and arrangement of the elements described without departing from the scope of the invention as set forth in the appended claims.
That said, the present invention relates to a method of increasing the performance of a quat-based liquid fabric softener through the addition of a quaternized poly-(meth)acrylic polymer thickener.
The present invention also relates to fabric softener compositions that minimally comprise quaternary surfactants, a cationic (meth)acrylic polymer thickener, and water, and that optionally comprise antifoams, preservatives, dyes and fragrances.
Quaternary Compounds Useful for Fabric Softening
In accordance with various embodiments of the present invention, the liquid fabric softener compositions comprise a quaternary ammonium cationic surfactant. For brevity, these cationic materials will be referred to as quaternary surfactants with the understanding that they are quaternized nitrogen species (i.e., cationic) and necessarily have an anionic counterion. In this regard, a variety of quaternary surfactants may be utilized. However, acyclic quaternary surfactants are preferred for fabric softener actives. For example, useful quaternary synthetic surfactants that are acyclic include linear alkyl, branched alkyl, hydroxyalkyl, oleylalkyl, acyloxyalkyl, diamidoamine, or diester quaternary ammonium compounds. The preferred quaternary surfactants for use in the present invention are the ester and diester quaternary surfactants and the diamidoamine quaternary blends. Cyclic quaternary materials such as the imidazolines are less preferred in the present invention but remain useful as softener actives. The quaternary surfactant actives in accordance with a preferred embodiment is at a level from about 1% to about 40% by weight of the fabric softener composition, and preferably from about 1% to about 10%, based on the total weight of the composition.
Examples of acyclic quaternary surfactant fabric-softening components useful in the present invention are shown by the general formulas (I) and (II):
wherein for general formula (I), R and R 1 are individually selected from the group consisting of C 1 -C 4 alkyl, benzyl, and —(C 2 H 4 O) x Z where x has a value from 1 to 20 and Z is hydrogen or C 1 -C 3 alkyl; R 2 and R 3 are each a C 8 -C 30 alkyl or R 2 is a C 8 -C 30 alkyl and R 3 is selected from the group consisting of C 1 -C 5 alkyl, benzyl, and —(C 2 H 4 O) x —H where x has a value from 2 to 5; and where X − represents an anion selected from the group consisting of halides, methyl sulfate, ethyl sulfate, methyl phosphate, acetate, nitrate or phosphate ion and mixtures thereof. Specific examples of quaternary surfactants described within the general formula (I) include alkyltrimethylammonium compounds, dialkyldimethylammonium compounds and trialkylmethylammonium compounds including but not limited to, tallow trimethyl ammonium chloride, ditallow dimethyl ammonium chloride, ditallow dimethyl ammonium methyl sulfate, dihexadecyl dimethyl ammonium chloride, di-(hydrogenated tallow) dimethyl ammonium chloride, dioctadecyl dimethyl ammonium chloride, dieicosyl dimethyl ammonium chloride, didocosyl dimethyl ammonium chloride, di-(hydrogenated tallow) dimethyl ammonium methyl sulfate, dihexadecyl dimethyl ammonium acetate, ditallow dipropyl ammonium phosphate, ditallow dimethyl ammonium nitrate, di-(coconut-alkyl)dimethyl ammonium chloride, cetyltrimethylammonium chloride, stearyltrimethylammonium chloride, distearyldimethylammonium chloride, lauryldimethylammonium chloride, and tricetylmethylammonium chloride, along with other quaternary compounds such as trihydroxyethylmethylammonium methosulfate, lauryldimethylbenzylammonium chloride, and the like.
Quaternary surfactants of the formula (II) are known as ester quats. Ester quats are notable for excellent biodegradability. In the formula (II), R 4 represents an aliphatic alkyl radical of 12 to 22 carbon atoms which has 0, 1, 2 or 3 double bonds; R 5 represents H, OH or O—(CO)R 7 , R 6 represents H, OH or O—(CO)R 8 independently of R 5 , with R 7 and R 8 each being independently an aliphatic alkyl radical of 12 to 22 carbon atoms which has 0, 1, 2 or 3 double bonds. m, n and p are each independently 1, 2 or 3. X − may be a halide, methyl sulfate, ethyl sulfate, methyl phosphate, nitrate, acetate or phosphate ion and also mixtures thereof. Useful are compounds wherein R 5 is O—(CO)R 7 and R 4 and R 7 are alkyl radicals having 16 to 18 carbon atoms, particularly compounds wherein R 6 also represents OH. Examples of compounds of the formula (II) include methyl-N-(2-hydroxyethyl)-N,N-di-(tallow acyloxyethyl)ammonium methyl sulfate, bis-(palmitoyl)-ethylhydroxyethyl methyl ammonium methyl sulfate or methyl-N,N-bis(acyloxyethyl)-N-(2-hydroxyethyl)ammonium methyl sulfate. In quaternary surfactants of the formula (II) which comprise unsaturated alkyl chains, preference is given to acyl groups whose corresponding fatty acids have an iodine number between 5 and 80, preferably between 10 and 60 and especially between 15 and 45 and also a cis/trans isomer ratio (in % by weight) of greater than 30:70, preferably greater than 50:50 and especially greater than 70:30. Commercially available examples are the methylhydroxyalkyldialkoyloxyalkylammonium methyl sulfates marketed by Stepan under the Stepantex® brand or the Cognis products appearing under Dehyquart® or the Evonik products appearing under Rewoquat®. Further ester quats of use in the present invention have the formulas; [(CH 3 ) 2 N + (CH 2 CH 2 OC(O)—R) 2 ]X − or [(HOCH 2 CH 2 )(CH 3 )N + (CH 2 CH 2 OC(O)—R) 2 ]X − , where R=linear saturated or unsaturated alkyl radical of 11 to 19 and preferably 13 to 17 carbon atoms. In a particularly preferred embodiment the fatty acid residues are tallow fatty acid residues. X − represents either a halide, for example chloride or bromide, methyl phosphate, ethyl phosphate, methyl sulfate, ethyl sulfate, acetate, nitrate, phosphate and also mixtures thereof.
Further useful acyclic quaternary ammonium fabric-softening agents include the diester quats of the formula (III), obtainable under the name Rewoquat® W 222 LM or CR 3099, which provide stability and color protection as well as softness:
Wherein R 21 and R 22 each independently represent an aliphatic radical of 12 to 22 carbon atoms which has 0, 1, 2 or 3 double bonds.
It is likewise preferable to use amidoamine quaternary surfactants of the formula (IV):
wherein R 17 may be an aliphatic alkyl radical having 12 to 22 carbon atoms with 0, 1, 2 or 3 double bonds, s can assume values between 0 and 5, R 18 and R 19 are, independently of one another, each H, C 1-4 -alkyl or hydroxyalkyl. Preferred compounds are fatty acid amidoamines such as stearylamidopropyldimethylamine obtainable under the name Tego Amid® S18, or the 3-tallowamidopropyltrimethylammonium methyl sulfate obtainable under the name Stepantex® X 9124, which are characterized not only by a good conditioning effect, but also by color-transfer-inhibiting effect and in particular by their good biodegradability. Particular preference is given to alkylated quaternary ammonium compounds in which at least one alkyl chain is interrupted by an ester group and/or amido group, in particular N-methyl-N-(2-hydroxyethyl)-N,N-(ditallowacyloxyethyl)ammonium methyl sulfate and/or N-methyl-N-(2-hydroxyethyl)-N,N-(palmitoyloxyethyl)ammonium methyl sulfate.
In preferred embodiments, the present inventive liquid fabric softener compositions comprise Rewoquat® WE-18 (from Evonik), Incrosoft® T-90 from Croda, any of the Stepantex® brand diester quats from Stepan, or any of the Accosoft® diamidoamine quats from Stepan, or mixtures thereof, as the quaternary surfactants, preferably present to achieve a total actives level of from about 1% to about 40 wt. %, and more preferably from 1 wt. % to about 10 wt. %, by weight based on the entire composition.
Cationic Thickener
The cationic thickeners for use in the present invention are quaternary (meth)acrylic polymers having the general structure (V):
wherein;
R 4 denotes H or CH 3 ;
Y denotes O or NH;
Z denotes: a linear alkyl chain of methylene units (CH 2 ), where x is an integer from 2 to 18; a substituted alkyl chain from 2 to 18 carbons in length having at least one hydroxyl group anywhere along the chain length; a benzene ring wherein the Y and the N substituents attach to the intervening benzene ring in a para relationship; or, a branched alkyl chain having a total number of carbons atoms from 2 to 18 carbon atoms; R 1 , R 2 , and R 3 are, independently, —CH 3 , —CH 2 —C 6 H 5 , —C 2 H 5 , -n-C 6 H 13 , -n-C 10 H 21 , -naphthalenyl, -benzofuranyl, or —CH 2 —C 6 H 4 —CH 2 —O—C 6 H 4 —CHO;
X denotes an anion chosen from the group consisting of halides (Cl, Br, I), sulfates (½SO 4 , HSO 4 ), methosulfate (MeOSO 3 ), trifluoromethane sulfonate (triflate, or “Tf”), tetrafluoroborate (BF 4 ), carbonates, bicarbonates, and mixtures thereof; and n (degree of polymerization) may be between several hundred to about 100 million.
Examples of polymers fitting this general structure (V), and hence useful in the present inventive composition and method, will be discussed below. It's important to note that the polymers for use in the present invention may be homopolymers and/or co-polymers. If the quaternized polymers used herein are co-polymers, the polymer structure may be random or block, with randomly interspersed nonionic monomers or blocks of nonionic oligomers. That is, the quaternary (meth)acrylic structure (V) may be only an oligomeric subunit of a co-polymer that also incorporates nonionic monomers and/or oligomers. Useful polymers are discussed in W. Jaeger, et al., Progress in Polymer Science, 35 (2010), 511-577, page 524 of the article, for example the polymers that the authors denote as 54a-h, 54k-m, 55a-f, 56, 57a-c, and 58, along with each of the co-polymers discussed in sections 3.1.3.2 and 3.2 of the article. The polymers and co-polymers disclosed in the Jaeger publication are incorporated herein by reference. Additional discussion of these useful polymers and other useful polymers for the present invention, may be found in U.S. Pat. No. 7,901,697 (Banetti, et al.), U.S. Pat. No. 7,491,753 (Krishnan), U.S. Pat. No. 6,329,483 (Schade, et al.), U.S. Pat. No. 5,608,021 (Uchiyama, et al.), and U.S. Pat. No. 5,169,540 (Fillipo, et al.), each incorporated herein by reference.
As understood in the chemical arts, the term (meth)acrylic is meant to include all acrylate, acrylamide, methacrylate, and methacrylamide substances, which is why the general structure (V) above features variable Y and R 4 groups and defines them so as to incorporate each of the acrylate, acrylamide, methacrylate, and methacrylamide polymers. “Quaternized” is the term given to a compound having a nitrogen atom with four (4) appendages and therefore a permanent positive charge. Consequently, there is a negatively charged counter-ion associated with each quaternized nitrogen atom in the cationic polymer. Synthesis of such quaternized (meth)acrylic polymers is found in the literature and includes, amongst other routes, both the polymerization of pre-quaternized monomers and the quaternization of polymers having appending tri-substituted amino groups with a reactant such as methyl chloride or benzyl chloride.
Preferred quaternary (meth)acrylic polymers for use in the present fabric softener composition include, but are not limited to poly[{2-(methacryloyloxy)ethyl}trimethylammonium chloride], poly[{2-(acryloyloxy)ethyl}trimethylammonium chloride], poly[{3-(methacryloyloxy)propyl}trimethylammonium chloride], poly[{3-(acryloyloxy)propyl}trimethylammonium chloride], poly[{2-(methacrylamido)ethyl}trimethylammonium chloride], poly[{2-(acrylamido)ethyl}trimethylammonium chloride], poly[{3-(methacrylamido)propyl}trimethylammonium chloride], and poly[{3-(acrylamido)propyl}trimethylammonium chloride], and mixtures thereof, each as homopolymers or as block or random co-polymers with various nonionic monomers. Such polymers are available commercially as Polygel® K-200 from 3V Sigma, Rheovis® CDE, CDP, and CSP from CIBA-BASF, and as Zetag™ 7109 from CIBA-BASF, amongst others. The quaternized (meth)acrylic polymers are incorporated in the liquid fabric softener at from about 0.01 wt. % to about 2 wt. % actives, based on the total weight of the composition. Preferably the cationic polymer is used at a level of from about 0.01 wt. % to about 0.5 wt. %. These quaternary (meth)acrylic polymers give an unexpected fabric softening effect and provide a way to cost-optimize liquid fabric softener products by reducing the level of quaternary surfactant and making up for the performance loss by the addition of the polymer. This unexpected benefit of fabric softening allow the use of these quaternary (meth)acrylic polymers as fabric softener actives.
Unsuitable cationic polymers include cationic guar polymers, cationic cellulose derivatives, cationic starches and cationic chitosan derivatives because they do not comprise structural similarity to the quaternary surfactant fabric softeners and are thus not expected to possess dual functionality of fabric softener and rheology modifier.
Optional Ingredients
Inorganic Stabilizers
The present invention may comprise one or more inorganic stabilizers. Such materials include, but are not limited to, calcium chloride and various borates. These inorganic materials are incorporated at from about 0.001 wt. % up to about 1 wt. %, based on the total weight of the composition.
Anti-Foam Agents
Antifoam is an optional ingredient for the compositions of the present invention. Any silicone emulsion antifoam typically used for aqueous compositions finds use in the present invention. Most useful are the antifoam emulsions available from Dow Corning. The preferred silicone antifoam for use in the present invention is Dow Corning® 1430 Antifoam, although Dow Corning® AC-8016 Antifoam, Dow Corning® Q2-3302 Antifoam Compound, Dow Corning® Q2-3425 Antifoam Compound, Dow Corning® DSP Antifoam Emulsion, Dow Corning® BF20 PLUS Antifoam Emulsion, Dow Corning® 544 Antifoam Compound, Dow Corning® DB-310 Antifoam Compound, and Dow Corning® 1520 Silicone Antifoam along with any other similar industrial or food grade silicone defoamer find use in the present invention. These types of materials mentioned help reduce foaming in the rinse cycle of the laundry operation when incorporated in the fabric softener composition. Preferably the antifoam is present in the composition from about 0.0001% to about 0.01% by weight, based on the total weight of the composition.
Antimicrobial Agent
Examples of antimicrobial agents that find use in the present invention include glutaraldehyde, formaldehyde, 2-bromo-2-nitropropane-1,3-diol sold under the trade name Bronopol®, 5-chloro-2-methyl-4-isothiazoline-3-one and 2-methyl-4-isothiazoline-3-one sold under the trade name Kathon®, and mixtures thereof. The preferred level for the antimicrobial is from about 0.001% to about 0.1%, or at that level recommended by the supplier of the particular antimicrobial and/or suggested in the supplier technical literature as that level required for optimally preserving aqueous surfactant compositions from mold and bacterial growth. The preferred antimicrobial for use in the present invention is glutaraldehyde and is best when incorporated from about 0.01% to about 0.10%. Most preferred in the present invention is to use Ucarcide® 250 brand of 50% glutaraldehyde solution and to add it at 0.050% by weight, based on the entire composition, resulting in an active level of glutaraldehyde of about 0.025%.
Fragrances
Fragrance is an optional ingredient for the fabric softener compositions of the present invention. For consumer acceptance, product recognition and recall, and most importantly to impart substantive fragrance to the fabrics inside the laundry washing machine, a fragrance is preferably added to the liquid fabric softener compositions of the present invention. Depending on the strength of the fragrance and the character of the perfume notes, the preferred amount of fragrance is from about 0.01% to about 3% by weight, based on the entire composition. Some preferred fragrances include, but are not limited to, UN063503/00, UN063507/00, UN063506/00, UN063511/00, UN063505/00, and UN063513/00 from Givaudan Fragrances, and Fressia-497 (from International Flavors and Fragrances).
Dyes
Dyes are optional ingredients within the compositions of the present invention. Dyes may comprise pigments, or other colorants, chosen so that they are compatible with the acidic pH of the final composition and such that the color is not attracted to the fabric. For example, a preferred colorant for use in the present invention is Liquitint® Green FS (from Milliken), at from about 0.001% to about 0.01% by weight, based on the entire composition. Other dyes such as C.I. Pigment Green #7, C.I. Reactive Green #12, F D & C Green #3, C.I. Acid Blue #80, C.I. Acid Yellow #17, Liquitint® Red MX, F D & C Yellow #5, Liquitint® Violet LS, Fast Turquise GLL, Liquitint® Blue MC, or mixtures thereof are also useful in the compositions of the present invention.
TABLE 1 delineates non-limiting examples of fabric softening compositions of the present invention, wherein cationic thickeners provide both fabric softening and thickening to the quaternary surfactant-based liquid fabric softener.
TABLE 1
Exemplary Liquid Fabric Softener Compositions
Ingredients (in weight
Formulations
percent actives)
A
B
C
D
E
Quaternary surfactant 1
10.00
4.44
6.50
8.00
9.50
Cationic thickener 2
0
0.15
0.15
0.15
0.15
Inorganic stabilizers,
+
+
+
+
+
defoaming agent
Water, fragrance,
q.s.
q.s.
q.s.
q.s.
q.s.
dyes, preservatives
Total
100.0
100.0
100.0
100.0
100.0
Softening Score
4.78
4.45
4.48
5.06
5.17
Table Notes:
1 Rewoquat ® WE-18 from Evonic;
2 Polygel ® K-200 from 3V
METHODS, RESULTS AND DISCUSSION
To test softness, approximately 50 cotton washcloths are washed in a washing machine using a typical laundry detergent followed by the test liquid fabric softener in the rinse cycle. The laundered washcloths are subsequently dried in an electric dryer. 12 washcloths are stacked and placed on a table for panelists to feel and rate. The test is run in duplicate and blind. Panelists are asked to rank the level of softness on a scale from 1-9, with 1 being unacceptable and 9 being perfectly soft to the touch. The numbers are averaged and statistically analyzed. The data were also inputted into 3D surface plot DOE to probe for synergies between the fabric softening quaternary surfactant and the cationic quaternary (meth)acrylic polymer thickener.
From analysis of FIGS. 1 and 2 , it is evident that quaternary (meth)acrylic thickener functions as a fabric softener. Indeed, even the control formula A having 10% active quat softener and no thickener may be boosted in performance from softness scores of 4.78 up to a theoretical 6.1 by the addition of about 0.25 wt. % quaternary (meth)acrylic polymer. Lower active quat softeners, for example having only about 6.0 wt. % quaternary surfactant actives, may be boosted in performance by addition of only about 0.35 wt. % quaternary (meth)acrylic polymer. As can be seen in the 3D surface plots, it is possible to formulate a cost-reduced liquid fabric softener having only 6.0 wt. % active esterquat and only about 0.35 wt. % actives quaternary (meth)acrylic polymer yet still have softness scores greater than the scores possible with 10 wt. % quaternary surfactant actives and no quaternary (meth)acrylic polymer.
I have thus demonstrated that certain quaternary (meth)acrylic polymers not only function as fabric softeners but actually boost softness performance to such an extent that synergy between the fabric softening quat and the cationic polymer is suggested. Certain quaternary (meth)acrylic polymers may therefore be used as fabric softeners, may be used to boost the performance of low-actives quaternary surfactant-based fabric softeners, all while providing the expected benefit of thickening.
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The present invention is method of boosting the performance of a cost-reduced liquid fabric softener comprising a quaternary surfactant fabric softener by adding a quaternary (meth)acrylic polymer that functions dually as a fabric softening active and a rheology modifier. In particular, poly[{2-(methacryloyloxy)ethyl}trimethylammonium chloride], poly[{2-(acryloyloxy)ethyl}trimethylammonium chloride], poly[{3-(methacryloyloxy)propyl}trimethylammonium chloride], and poly[{3-(acryloyloxy)propyl}trimethylammonium chloride] provide synergistic fabric softening with quaternary surfactants to provide superior fabric softening scores from cost-optimized compositions.
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BACKGROUND OF THE INVENTION
There has for a long time been a need for a portable dance floor, which can be assembled and positioned wherever and whenever needed, and later can be readily disassembled and stored for later use. Hardwood flooring, preferred for dancing, is easily marred by those walking on it, and so it is not used as a permanent flooring where there is much foot traffic and only occasional dancing. In hotels and recreation centers, rooms for banquets or conferences are frequently carpeted from wall to wall to provide comfortable walking and to reduce noise. Dancing is not possible on carpets and accordingly a quick setup/break down dance floor is needed to accommodate dancing. Prior to now the available portable dance floors have had many flaws, principally relating to the means for joining sections so as to produce a level dancing surface, free of irregularities in height and spacing of adjoining sections. Other problems develop when Allen head screws used to join adjacent dance floor sections become too worn for the wrenches to work well and when threads become stripped.
It is an object of this invention to provide a novel portable dance floor. It is another object to provide a portable dance floor that has improved joining means between sections so as to produce a level top surface and perfect joining surfaces. Still other objects will become apparent from the more detailed description which follows.
BRIEF SUMMARY OF THE INVENTION
This invention relates to a portable dance floor comprising a plurality of assemblable identical square sections and a plurality of ramp members attachable to said sections to form a sloping perimeter around the dance floor, each said square section having a top horizontal surface, a bottom horizontal surface, and four vertical side surfaces including a generally square central core sheet of weight supporting material with a dance floor material covering its top surface, a structural beam portion around its perimeter to which are attached cooperating magnetic attraction means adapted to detachably join said square sections to each other and to detachably join said ramp members to said square sections.
In specific and preferred embodiments of this invention the dance floor sections have a light weight plastic honeycomb material as a core, a top surface of hardwood flooring and sides of wood, aluminum, or plastic beams to which are affixed magnets, wedge-shaped tongues, and recesses to provide a tight, accurately positioned coupling between adjoining sections.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features believed to be characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings in which:
FIG. 1 is a top plan view of the dance floor of this invention including four joined dance floor sections and ramps around the perimeter;
FIG. 2 is a side elevational view of the dance floor of FIG. 1;
FIG. 3 is a top plan view of one dance floor section;
FIG. 4 is a side elevational view of the one section shown in FIG. 3;
FIG. 5 is a front elevational view of the section shown in FIGS. 3-4;
FIG. 6 is a cross sectional view taken at 6--6 of FIG. 3 using metal structural beams;
FIG. 7 is a cross sectional view taken at 7--7 of FIG. 3 using metal structural beams;
FIG. 8 is a cross sectional view taken at 8--8 of FIG. 3 using metal structural beams;
FIG. 9 is a cross sectional view taken at 9--9 of FIG. 3 using metal structural beams;
FIG. 10 is a cross sectional view taken at 10--10 of FIG. 3 using metal structural beams;
FIG. 11 is a cross sectional view taken at 6--6 of FIG. 3 using wooden structural beams;
FIG. 12 is a cross sectional view taken at 8--8 of FIG. 3 using wooden structural beams;
FIG. 13 is a cross sectional view taken at area 37 of FIG. 1 looking vertically downward below the wooden dance flooring into the dance floor using metal beams;
FIG. 14 is a cross sectional view taken at 14--14 of FIG. 1 using metal beams;
FIG. 15 is a cross sectional view taken at 15--15 of FIG. 1 using metal beams;
FIG. 16 is a cross sectional view taken at 16--16 of FIG. 2 using metal ramp sections;
FIG. 17 is a cross sectional view taken at 17--17 of FIG. 2 using metal ramp sections;
FIG. 18 is a cross sectional view taken at 14--14 of FIG. 2 using wooden beams;
FIG. 19 is a cross sectional view taken at 15--15 of FIG. 2 using wooden beams;
FIG. 20 is a cross sectional view taken at 16--16 of FIG. 1 using wooden ramp sections; and
FIG. 21 is a cross sectional view taken at 17--17 of FIG. 1 using wooden ramp sections.
DETAILED DESCRIPTION OF THE INVENTION
This invention is best understood by refernece to the attached drawings,
In FIGS. 1-5 the general assembly and the component parts of the dance floor of this invention can be seen. The dance floor is made up of a plurality of square sections 20 abutting other identical sections to produce whatever shape is desired of the final assembly. Most of the time the final assembly is expected to be rectangular or square, although it can be imagined that the floor might be in the shape of the letter T or other simple shapes that can be produced by rearranging square sections 20. Inclined ramp sections 21 and 22 are attached to square sections 20 around the perimeter of the final dance floor. Square section has a top surface 38 which is a dancing surface, vertical sides and a bottom surface 40 which rests on whatever is under the dance floor assembly. Attached to the vertical sides on the outer perimeter of the assembly of sections 20 are ramp sections 21 and 22, which provide a sloping connection between the supporting floor and the top level of the assembled sections 20. This is not necessary for dancing purposes, but is a safety feature to prevent tripping or misstepping as one enters onto the dance floor or leaves it. There may be different precise designs of the ramp sections to accommodate different arrangements. For example, instead of the arrangement shown in FIG. 1 (4 center sections 21, 4 left hand sections 22, and 4 right hand sections 22) there may be no sections 21 and eight end sections 22, each long enough to cover one half the length of a side 42. If the dance floor is always the same size and shape, there may be four ramp sections, each being a combination of two end sections 22 and one center section 21.
The structure of square sections 20 is shown in FIGS. 3-5. Each section 20 is identical to each other section 20 so as to provide facility in assembly by not having to sort out one type of section 20 from another. Each section 20 has a basic core sheet 23 of supporting material, which preferably is a manufactured sheet of light weight plastic honeycomb material with the axes of the honeycomb cells being vertical and with precisely flat and parallel top and bottom surfaces 38 and 40, and may be sawed as wood is sawed. Other core materials suitable are wood, metal, plastic, paper, fiberglass reinforced plastic in solid, honeycomb, or foamed structures, and the like. Attached to sides of core sheet 23 are lengths of beams 26 or 29, preferably wood or aluminum, but may alternatively be steel, plastic, or the like, to form finished vertical sides 42 of square sections 20. These two components, core sheet 23 and side beams 26 and 29 constitute the basic structure of the square sections 20. A moisture barrier sheet 41 is laid across core sheet 23 to prevent liquids from running into core sheet 23 from above, and to provide additional strength. A danceable flooring material 24, preferably hardwood parquet sections 25 is laid across top surface of moisture barrier sheet 41 to provide the best dancing surface. Other dance floor materials, such as tile, plastic sheet, etc. may be used, but are not preferred over waxed hardwood. A cover sheet 33 may be attached to the bottom surface of square section 20 to provide a protection against damaging the main floor supporting the dance floor, and also to protect the underside of the portable dance floor section 20. The main floor might be of any common building materials such as wood, metal, concrete, tile, stone, etc., uncovered or covered with carpeting. Cover sheet 33, if used, preferably is a plastic sheet or film, or a felt fabric.
The remaining components on each square section 20 are magnetic means for firmly attaching one square section 20 to the next abutting square section 20. Other additional components include wedge lock means for aligning square sections 20 properly and preventing them from sliding laterally and dowel or tongue means for aligning ramp sections 21 and 22 with square sections 20.
FIGS. 6-12 show beams which are attached to the outer perimeter of central core 23 and provide means for attachment of the components to clamp adjacent square sections 20 together in proper alignment. Beams 26 and 29 are metal or plastic beams in FIGS. 6-10.
Beams 54 and 55 are wooden beams in FIGS. 11-12. Beams 26 are square hollow tubing and beams 55 are solid wooden square beams, each having a groove on the outside vertical face opposing the next abutting square section 20. The groove is for seating a ferrous, preferably iron or steel, strip or rib 27 which will cooperate with magnets on the abutting square section 20 to make a tight coupling. Strip 27 is attached to beam 26 or 55 by screws (see FIG. 13)45, or in the case of wooden beams 55 may be cemented into place. Beam 29 is an aluminum channel and beam 54 a wooden channel, each with the open side of the channel facing beam 26 or 55, respectively, and steel rib 27 of the next abutting square section 20. In channel of beam 29 or 55 a plurality of magnets 31 and backing buttons 32 are spaced over the entire length of the beam. Between adjacent magnets 31 and backing buttons 32 are nonmagnetic spacers 44 to maintain the desired spacing of the magnets 31 when in an aluminum channel. In the wooden beam 55 each magnet 31 and its backing button 32 is cemented into a countersunk hole in the beam. Preferably, magnets 31 are ceramic magnets made from rare earth elements. These magnets are very strong and have a long life. Backing buttons 32 are ferrous materials, like that of strip or rib 27, and their function is to strengthen the magnetic attraction field, which occurs merely by being in contact with magnet 31. These components are positioned, being of the appropriate size, to slidingly fit into the channel of metal beam 29, when such is used. There may, of course, be added, if desired, a more positive attachment than friction; for example, cement, rivets, screws, or the like. As may be seen in comparing FIGS. 6 and 11 with FIGS. 8 and 12, magnet 31 is recessed inwardly from the outside surface of the beam 29 or 54 (FIGS. 6 and 11) and strip or rib 27 projects outwardly from the outside surface of beams 26 and 55 (FIGS. 8 and 12). The recess in FIGS. 6 and 11 matches the projection in FIGS. 8 and 12, such that when magnet 31 and rib 27 are in contact, the corresponding outer faces of beams 26 and 29 (in the metal configuration) or 55 and 54 (in the wooden configuration) are also in contact. For a square section of about four feet on a side, there may be used four to eight magnets 31 spaced along the four foot side.
Beams 54 and 55 (FIGS. 11 and 12) are the wooden counterparts to beams 29 and 26 (FIGS. 6-10). The same combination of magnet 31 and backing button 32 are used in beam 54 as that of metal beam 29 in FIG. 6. However, magnet 31 and button 32 in FIG. 11 are cemented into a countersunk hole so as to prevent lateral sliding and also to elmininate the need for a spacer 44. In FIG. 12 beam 55 is a square or rectangular beam with a shallow groove on one face to accept iron or steel strip 27. Strip 27 may be screwed, cemented, or otherwise affixed to beam 55 to make it the counterpart of the metal or plastic combination of FIG. 8.
The wedge lock means for aligning two square sections 20 and preventing them from lateral sliding comprises a plurality of wedge-shaped tongues 28 in beams 29 and 54 mating with a plurality of wedge-shaped recesses 30 in strip 27 in beams 26 and 55 along plane 53 between sections 20 and ramps 21 or 22. The tongues 28, usually two being present on a side 42 of square section 20, are shaped to fit the channel of beams 29 and 54 and are slid into place with a section of spacer 44 on each end of tongue 28 in metal beam 29 or are cemented in place in wooden beams 54 (See FIGS. 9, 13, 14 and 18). Wedge shaped recesses 30 are the result of interrupting rib 27 with a space, bevelled at each end to fit the cooperating wedge-shaped tongue 28 (See FIGS. 3, 5, 13 and 14). It is easily seen that with tongues 28 in place, two abutting sections 20 may not slide laterally with respect to each other. Tongues 28 are preferably made of steel, like spacers 44 or may be made of wood. FIG. 13 is a cross sectional view looking downwardly in area 37 in FIG. 1 with the dance floor material removed. FIG. 13 shows the relationships of beams 26 and 29, magnets 31, backing buttons 32, spacers 44, tongues 28, rib 27 and recesses 30.
Ramp members 21 and 22, made of metal, are fashioned to mate with the components in metal beams 26 and 29. Ramp members 51 and 52, made of wood, are fashioned to mate with the components in wooden beams 54 and 55. It is, of course, entirely appropriate to mix metal beams with wooden ramps or wooden beams with metal ramps. FIG. 16 shows a ramp section having a channel beam face as in FIG. 6 and containing magnets 31 and backing buttons 32 in leg 35', support leg 36, and spacers 44 arranged as described above with respect to channel 29. FIG. 17 shows a ramp section having a face 35 similar to that of beam 26 in FIG. 8 and including rib 27 with square-shaped recesses 49. No ramp section 21 or 22 contains a wedge-shaped tongue 28 or a wedge shaped slot recess 30. However, in order to provide a better stability and alignment, ramps 21 and 22 contain a square recess 49 or a square tongue 50 to mate with a wedge-shaped tongue 28 or a wedge-shaped slot recess 30 in square section 20. FIGS. 14 and 18 illustrate the mating of a wedge-shaped tongue 28 on a square section 20 with a square recess 49 on ramp section 21, 22 or 51. FIGS. 15 and 19 illustrate a wedge-shaped recess 30 on square section 20 mating with a square tongue 50 on ramp sections 20, 21 or 52. These combinations are effective in preventing lateral sliding of a square section 20 with respect to a ramp section 20, 21, 51 or 52.
An additional aligning means that has been employed and found to be acceptable is the use of one or more dowels 56 on ramp sections 20, 21, 51 or 52 to mate with dowel alignment holes 57 on square section 20 or one of its components, such as wedge-shaped tongue 28 as illustrated in FIG. 18.
It is also a preferred addition to employ a light in each ramp section 21, 22, 51 or 52 as illustrated in FIGS. 17 and 21. A groove in the face 34 of the ramp is fitted with an end illuminated translucent rod 47, or alternatively, light bulbs are placed along the groove and a translucent cover plate 50 is placed flush with the top surface of the ramp section.
While the invention has been described with respect to certain specific embodiments, it will be appreciated that many modifications and changes may be made by those skilled in the art without departing from the spirit of the invention It is intended, therefore, by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention.
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A dance floor of assemblable square sections that are held together magnetically and are aligned by male/female couplers and ramp members attachable to the outer perimeter of the assembled square sections.
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[0001] A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the xerographic reproduction by anyone of the patent document or the patent disclosure in exactly the form it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to the field of customized information presentation. More specifically, one embodiment of the invention provides a custom page server which can quickly serve custom pages and is scalable to handle many users simultaneously.
[0003] Web servers for serving static documents (“Web pages”) over the global Internet are known. While static documents are useful in many applications where the information to be presented to each requesting user is the same, some applications require customization to appeal to users. For example, in presenting news to users, custom pages present news which is more relevant to the requesting users than static pages. With static pages, a user will often have to scroll through many topics not of interest to that user to get to the information of interest. With custom pages, the information is filtered according to each user's interest.
[0004] Customizing a server response based on the requestor is known, however known systems do not scale well. One method of serving custom pages is to execute a script, such as a CGI (Common Gateway Interface) script, or other program to collect the information necessary to generate the custom page. For example, if the custom page is a news page containing stock quotes, sports scores and weather, the script might poll a quote server to obtain the quotes of interest, poll a sports score server to obtain the scores of interest and poll a weather server to obtain the weather. With this information, the server generates the custom page and returns it to the user. This approach is useful where there are not many requestors and where the attendant delay is acceptable to users. While it may be the case that current users are willing to wait while pages load in their browsers, growing impatience with waiting will turn users away from such servers, especially as use increases.
[0005] One approach to avoiding long waits is to transfer the custom information in non-real-time, so that the information is stored local to the user as it arrives and is presented to the user on request. A disadvantage of such a system is that the networks used by the user become clogged with data continually streaming to the user and require large amounts of local storage. Another disadvantage is that the locally stored information will become out of date as the server receives new data.
[0006] From the above it is seen that an improved system for delivering custom pages is needed.
SUMMARY OF THE INVENTION
[0007] An improved custom page server is provided by virtue of the present invention. In one embodiment, user preferences are organized into templates stored in compact data structures and the live data used to fill the templates is stored local to the page server which is handing user requests for custom pages. One process is executed on the page server for every request. The process is provided a user template for the user making the request, where the user template is either generated from user preferences or retrieved from a cache of recently used user templates. Each user process is provided access to a large region of shared-memory which contains all of the live data needed to fill any user template. Typically, the pages served are news pages, giving the user a custom selection of stock quotes, news headlines, sports scores, weather, and the like. With the live data stored in a local, shared memory, any custom page can be built within the page server, eliminating the need to make requests from other servers for portions of the live data. While the shared memory might include RAM (random access memory) and disk storage, in many computer systems, it is faster to store all the live data in RAM.
[0008] If the volume of requests becomes too great for one page server to handle, the system is easily scaled by adding additional page servers. Each page server maintains its own copy of the live data in its shared memory, and needs to maintain only the user templates for the requests it is handling, so no communication between page servers is needed.
[0009] A further understanding of the nature and advantages of the inventions herein may be realized by reference to the remaining portions of the specification and the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a block diagram of a client-server architecture according to one embodiment of the present invention;
[0011] FIG. 2 is a schematic diagram showing how a user's custom page is generated from a user configuration, a global template and live data.
[0012] FIG. 3 is an illustration of a global front page template as might be used to generate user templates.
[0013] FIG. 4 is an illustration of a user template generated from the global front page template of FIG. 3 as might be used to generate a custom user page.
[0014] FIG. 5 is an illustration of a user page generated using the global template of FIG. 4 .
[0015] FIG. 6 is an illustration of how intelligent defaults are selected.
[0016] Two appendices are included at the end of this description. Appendix A is a full listing of the user template shown in part in FIG. 4 . Appendix B is an HTML source code listing of the HTML page used to generate the browser display shown in FIG. 5 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] FIG. 1 shows a client-server system 100 which is used to display custom news pages. A custom news page is displayed on a browser 102 which obtains the page from a page server 104 via Internet 106 . While only one browser 102 is shown, a typical system will have many browsers connecting and disconnecting to the system.
[0018] The art of client-server systems using HTTP (HyperText Transport Protocol) messaging or other protocols is well known and will not be addressed in detail here. Essentially, browser 102 makes a request for a particular page by specifying a Uniform Resource Locator (“URL”) for the page. In the example shown in FIG. 1 , the request is directed to the URL “http:/my.yahoo.com/”. Normally, this URL is directed to the root directory of a machine named my.yahoo.com. As is the convention in Internet communications, browser 102 submits the domain portion (“my.yahoo.com”) of the URL to a name server, such as name server 108 , to determine an actual address for the page server 104 . Name server 108 returns an IP (Internet Protocol) address to browser 102 directing it to a page server 104 . Where multiple page servers 104 are used, name server 108 returns IP addresses in a round-robin fashion to distribute the load over multiple page servers. Alternatively, name server 108 might distribute the load more deterministic by tracking browser addresses and hashing the browser address to select a page server 104 . It is deterministic in that any given browser always accesses the same page server 104 . This allows for more efficient caching of user templates, since more cache hits are likely where a given browser always returns to one page server.
[0019] When a page server receives the URL for its root directory, it interprets that as a request for the user's custom summary page. The user is determined not from the URL, but from a “cookie” provided by browser 102 with the URL. Cookies are strings of data stored by browsers and sent along with any request to a URL having a domain associated with the cookie.
[0020] Page servers 104 obtain the live data from many disparate sources and reformat the data into a form suitable for use by the page server. Page servers 104 are coupled, via a network, to edit servers 112 , which are used when a user changes his or her user template. The user templates are stored in a user configuration database 116 and are stored and provided to edit servers by a network appliance 114 written for this purpose. Network appliance 114 is a process tuned to quickly locate files in large directories (N400 files/directory) and return them to the edit servers or page servers. One embodiment of network appliance 114 is the F330 fault-tolerant scalable server supplied by Network Appliance, of Mountain View, Calif.
[0021] In a specific embodiment, page servers 104 are microcomputers running the Unix® operating system with 64 to 128 megabytes of shared memory, page servers 104 and edit servers 112 are coupled using TCP/IP (Transport Control Protocol/Internet Protocol) and the user configuration database 116 is a Unix file structure which stores each user configuration in a text file. The particular file used by a user is a combination of the user's user name and a hash result, to allow for quick access when many user configurations are stored. For example, the user configuration for summary “front” page for a user “ash802” might be stored at /de/13/y.ash802, where “de” and “13” are hash results of a hash of the user name “ash802”.
[0022] FIG. 2 shows in more detail the generation of a custom page for a user, using a front page generator 200 and page server 104 . Front page generator 200 generates a user template 202 from a global front page template 204 and a user configuration record 206 . FIG. 3 shows an example of a global front page template. User configuration record 206 is a record selected from user configuration database 116 . The record might have been obtained from a cache, but in the preferred embodiment, the records are not cached, the user templates are.
[0023] Page server 104 is shown comprising a page generator 210 , a shared memory 212 for storing live data and a cache 214 for caching user templates such as user template 202 . Page generator 210 generates a custom front page 218 from a user template and the live data stored in shared memory 212 . Although not shown, custom pages other than the front page can be generated in a similar fashion. Using user templates and a shared memory for the live data, page server 104 can quickly build custom pages in response to a user request. Where the user template is cached, the page can be generated entirely within page server 104 .
[0024] Shared memory 212 is organized as a set of memory mapped files. With memory mapped files, the operating system maintains the data in permanent storage, but permanently caches the files in shared memory 212 . This allows for quick recovery should a page server crash, since all of the shared memory can simply be reloaded from the permanent storage. This is a great feature from a user convenience standpoint, since the user will never be faced with a situation where they have to wait for a server to rebuild a page for them by querying the various data providing servers, such as sports server 230 , stock server 232 and news server 234 . As should be apparent from this description and FIG. 2 , page generator 210 can generate custom front page 218 much more quickly using shared memory 212 as compared with using servers 230 , 232 , 234 and page template 202 . One reason for this is that the time it takes to retrieve data from shared memory 212 does not appreciably increase relative to the bandwidth delay time when more data is retrieved. For example, if stock server 232 were queried for each individual stock quote, a page with fifty stock quotes might take ten times as long to generate as a page with five stock quotes.
[0025] One aspect of the present invention is the realization that every piece of information a person can request on a page is storable in a shared memory closely coupled to a page generator. For example, page server 104 shown in FIG. 2 can accommodate 65,000 different symbols for which quotes are provided. In one embodiment, all of the stock information for all 65,000 symbols is stored in a 13 to 14 megabytes section of the shared memory. Where shared memory 212 is a 64 MB or 128 MB memory, this leaves sufficient room for other data, such as news headlines, sport scores, and memory used by the operating system for each process running on page server 104 . In some embodiments, shared memory 212 is large enough to also accommodate more than just news headlines. For example, news summaries (as described further in connection with FIG. 5 ) can be stored in shared memory 212 for quick access.
[0026] As shown in FIG. 2 , the user's front page template 202 does not need to be generated each time, but rather is stored in cache 214 . In a preferred embodiment, user templates are stored in cache 214 for long enough to be reused. Some users might choose to access their front page only infrequently, while others might choose to access their front page hourly. Since the pages are customized and dynamic, the user would see different information each time, but the same user template would be used each time. Of course, when the user edits his or her template, any cached copy of a user template is flushed. A garbage-collection process may also flush the cache of user pages which have been inactive for several days. In one implementation, cache 214 would accommodate 60,000 to 70,000 user templates. Where a particular page server is assigned on a random round robin basis, multiple page servers may cache their own copy of a given user template, but where a user is directed always to a particular server (except in the case where the particular server fails and a secondary server is used), that page server will be the only one which needs to cache that users user template. Even where the round robin name server scheme is used, some browsers may cache IP addresses, even longer than the specified “time to live” variable associated with the IP address, in order to save the time required to obtain an IP address each time. With such a browser, the user is effectively directed to the same page server each time and the server side of the page serving system does not need to direct users to particular page servers. With newer browsers, however, the “time to live” variable is honored and new requests are made for IP addresses after the “time to live” has expired. In these cases, if the assignment of a user to a single page server is desired, name server 108 (see FIG. 1 ) will use the user name from the provided cookie or the user's IP address to assign a page server based on a hash of the user name or IP address.
[0027] FIG. 3 is an illustration of global user template 204 . Global user template 204 is an HTML (HyperText Markup Language) document with additional tags as placeholders for live data. Several placeholders 302 are shown in FIG. 3 .
[0028] FIG. 4 is an illustration of user template 202 as might be generated from global user template 204 (see FIG. 3 ) and a user configuration record 206 . A full listing of user template 202 is included herewith in Appendix A. User template 202 is determined by the user configuration and is independent of the live data, therefore it can be cached without needing to be updated, unless the user chooses to edit the configuration information. Preferably, the user templates are cached rather than the user configuration, to save a step and reduce the time to respond to a request for the page. Caching is more effective where the typical user makes several requests in a short time span and then doesn't make any requests for a long period of time.
[0029] Essentially, user template 202 contains the information about the user which does not change until the user changes his or her preferences. Of course, the system operator could choose to make changes to how the system operates, thus requiring changes to the user preferences and user templates. User template 202 is shown comprising internal variables such as a time zone and demographic information. The demographic information, on the second line in FIG. 4 is used for selection of an advertisement which will be part of the custom page. In this example, the advertisement is targeted by the demographic information in the user template “:M,85,95035,T,*” indicating that a suitable ad should be targeted to a male user, age 85, located in zip code 95035, etc. As shown, the portfolio section contains selected stock symbols, the scoreboard section contains selected team symbols, and the weather section contains selected weather cities/zip codes.
[0030] The selections of stock quote symbols, team scores, and weather cities are set by the user. In a preferred embodiment, intelligent defaults are selected by the system prior to user selection, so that users unfamiliar with the customization process will nonetheless be able to view non empty custom pages. This is described in further detail below in connection with FIG. 6 .
[0031] FIG. 5 is an illustration of a user front page 218 returned by page server 104 . User front page 218 as shown in FIG. 5 includes many elements, some of which are described here in further detail. User front page 218 is built according to a user template and live data. The user template specifies, for example which quotes are shown in the portfolio module, which cities are displayed in the weather module, etc. Each of the modules 504 can be customized by a user and moved about front page 218 . The modules 504 are also reusable, in that any customized module which appears on multiple pages can be edited from any one of those pages and the edits will be reflected on each of the pages. Other custom pages for the user can be viewed by selecting one of the page buttons 502 appearing below the header. Other pages and utilities can be selected using the buttons 508 which are part of the header.
[0032] In addition to all of the live date shown in FIG. 5 being stored in the shared memory, summaries from each of the major news topics can also be stored in the shared memory and viewed by pressing on the news topic header, such as news topic header 506 . As should be noted, the page generator can also intelligently display dates 510 customized for a particular user, using a time zone variable in the user template. This time zone variable is shown as the first line in user template 202 in FIG. 4 . In addition to being able to modify each of the modules, in many cases the order of appearance of the modules is customizable. For example, the order of the various sections of user template 202 shown in FIG. 4 is not fixed.
[0033] The preference editing process can be initiated by the user pressing the appropriate edit button 512 . As explained above, once the editing process is complete, the user template is flushed from the cache and regenerated. Since each of the news stories is essentially a static page linked to a headline shown in the news section, these can simply be linked to static pages on a news server.
[0034] Referring now to FIG. 6 , an illustration of intelligent defaulting for populating a user template, and consequently a user summary page. As part of a registration process, a user indicates, among other things, his or her zip code. This zip code is used to locate an approximate longitude and latitude for the user using a zip code lookup table 602 . This allows the user's location to be located on a map 604 . Map 604 provides city boundaries and, with team location table 606 , also provides locations for various sports teams which can be selected in a sports module. In selecting a default predetermined number of cities and sports teams for inclusion as initial selections for a particular user, a circle is drawn around the user and increased in diameter until the circle envelopes a suitable predetermined number of cities and sports teams. In this way, each user is guaranteed a default number of nearby teams and cities for sports and weather, respectively. While this assumes that the user is interested in only the teams nearest the user, the system can be arranged to provide intelligent defaults where geographic anomalies are known to exist. Geographic anomalies occur in communities which have more loyalty to distant teams than nearby teams, such as might occur when the distant team is much better than the nearby team or when the nearby team recently moved to a distant location. In any case, the user is allowed customize his or her pages beginning with the intelligent defaults selected.
[0035] Other intelligent defaults can be provided in other contexts. For example, the header of user front page 218 includes a button 508 labelled “myweb” which, when pressed, would lead the user to a custom listing of web sites. The initial defaults for that custom listing of web sites might be generated based on the keywords of interest to that user or based on the news topics, sports teams or weather cities selected by the user.
[0036] The above description is illustrative and not restrictive. Many variations of the invention will become apparent to those of skill in the art upon review of this disclosure. The scope of the invention should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the appended claims along with their full scope of equivalents.
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An custom page server is provided with user preferences organized into templates stored in compact data structures and the live data used to fill the templates stored local to the page server which is handing user requests for custom pages. One process is executed on the page server for every request. The process is provided a user template for the user making the request, where the user template is either generated from user preferences or retrieved from a cache of recently used user templates. Each user process is provided access to a large region of shared memory which contains all of the live data needed to fill any user template. Typically, the pages served are news pages, giving the user a custom selection of stock quotes, news headlines, sports scores, weather, and the like. With the live data stored in a local, shared memory, any custom page can be built within the page server, eliminating the need to make requests from other servers for portions of the live data. While the shared memory might include RAM (random access memory) and disk storage, in many computer systems, it is faster to store all the live data in RAM.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of copending application Ser. No. 616,307 filed Sept. 24, 1975 now abandoned; which is a continuation of application Ser. No. 492,011 filed July 26, 1974 (now abandoned); which is, in turn, a continuation of application Ser. No. 267,227 filed June 28, 1972 (now abandoned); which is a continuation of application Ser. No. 64,475 filed Aug. 17, 1970 (now abandoned).
BACKGROUND OF THE INVENTION
In the production of synthetic pile fabrics, it is often desirable to emboss the surface thereof in order to provide added decorative appeal. In some instances, the embossed areas are printed with dyes to further embellish the surface design.
Embossing of pile fabrics is conventionally accomplished with a heating embossing roll or plate which has been engraved or otherwise treated to create the design desired in raised relief on the surface. A method which eliminates the use of embossing rolls has been disclosed in U.S. Pat. Nos. 2,790,255 and 2,875,504.
In accordance with these patents, the pile fabric is formed from a combination of shrinkable and non-shrinkable yarns. Upon subjecting the fabric to the influence of heat, the pile formed from the shrinkable yarns contracts while the base and the non-shrinkable yarns remain intact thereby yielding a pile made up of high and low areas to give the appearance of an embossed or carved product.
A chemical embossing method is disclosed in U.S. Pat No. 2,020,698. According to this patent, fabric having a pile of organic ester of cellulose yarn is locally treated with an alkali or alkaline salt saponifying agent in order to obtain ornamental differential effects in the treated areas. Furthermore, since the organic ester of cellulose pile yarns that have not been saponified are more difficult to change from their position, after they are once set than are the saponified organic ester of cellulose yarns, it is possible to obtain a differential lay between the saponified and unsaponified organic ester of cellulose pile yarn. Thus, the fabric, after the application of the saponifying agent, may be washed, finished and dried with the pile erect, after which the fabric may be run through water and brushed across the piece to lay the pile towards the selvage and is then dried. This causes the saponified pile yarn to lie flat while the unsaponified yarn remains substantially erect. Upon subsequent steaming and cross-brushing the fabric in the opposite direction, any unsaponified yarn which may have been slightly bent from the vertical by tbe previous brushing toward the selvage is caused to stand erect without disturbing the position of the laid or crushed saponified organic ester of cellulose pile yarn.
SUMMARY OF THE INVENTION
It is the primary object of this invention to provide a simple process for producing a synthetic pile fabric having a textured or embossed surface. Another object is to provide such a process which is readily adaptable to standard printing equipment. Another object is to provide a process which allows the production of pile fabric having emobossed areas in register with a printed design. A further object is to provide an embossing process which is readily adaptable to curved and irregular surfaces. A still further object is to provide a novel, embossed pile fabric. Various other objects and advantages of this invention will be apparent from the following detailed description thereof.
It has now been discovered that it is possible to produce superior pile fabrics having embossed surfaces by contacting selected portions of the surface with a chemical embossing agent for the fibers of said pile fabric causing dimensional change by linear contraction of the treated fibers and thereafter effectively removing the embossing agent. The resulting product is thus depressed at the treated areas.
The embossing composition can be transparent so that the appearance of the product is not altered other than in being embossed. Alternately, the embossing agent can be part of a dye or pigment composition so that the color appears in the areas of embossing agent application.
The depth of the depressed areas can be controlled by varying the concentration and/or type of embossing agent. This varied concentration can be effected by the amount of vehicle applied as well as by the strength of the embossing reagent.
Furthermore, the embossed depth can be controlled by varying the temperature to which the pile fabric is subject in order to activate the chemical embossing agents which provide the desired effect.
This discovery makes possible the production of a product having embossed surfaces which can be in complete register with a printed design. Additionally, the discovery makes possible the utilization of many types of printing apparatus for purposes of effecting embossing, thereby eliminating the need for expensive embossing equipment. Further, it allows the embossing of a surface without exerting sufficient pressure to permanently deform the pile fabric. A great number of products can be produced by the process. It can be used for producing floor, wall and ceiling coverings, drapery, upholstery and the like, and, in fact wherever such pile fabrics are utilized. It is readily adaptable to decorating any surface on which pile fabrics can be applied. Many additional applications will occur to those skilled in the art.
This invention will be better understood from the following detailed description thereof together with the accompanying self-explanatory drawing in which:
FIG. 1 is an enlarged top view of a section of an embossed product of this invention; and,
FIG. 2 is an enlarged cross-sectional view of the same product taken through line 2--2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the production of the pile fabrics of this invention the pile yarns employed are the polyamides such as nylon.
Likewise, the embossing agents which are applied to the fibers in order to produce the desired effect are also known. For purposes of this invention, the term "embossing agent" is defined as any active chemical composition which when applied to the pile fabric produces a measurable reduction of pile height involving linear contraction of the fibers, and includes, among others, substances which are known to be swelling agents for the specified synthetic fibers.
In order to be applicable for the novel process of this invention, the ideal embossing agent should provide alteration, and indeed, irreversible alteration, of the fiber dimensions through the chemical reaction described hereinabove, should not adversely affect the printing means, e.g. print screens, and should be capable of being substantially removed or inactivated subsequent to the embossing action. Other characteristics of the embossing agent which are desirable, though not essential, include compatibility with dye print pastes, the capability of being regulated by factors of time, temperature and concentration, i.e. being susceptible to activation by a conventional steaming operation and exhibiting no residual embossing activity. Needless to say, minor adjustments in the nature of the components and process conditions, and/or the embossing apparatus can overcome the absence of certain of these desired characteristics.
Thus, embossing agents effective on nylon include halogenated acetic acids such as chloroacetic and trifluoroacetic acids.
The embossing agent for the synthetic fibers is applied to one surface of the pile fabric in any desired design, whether it be random or predetermined. One of the easiest methods of applying the agent is by utilizing some of the conventional printing techniques such as screen or block printing. The embossing agent can be applied as a concentrate, as part of a transparent vehicle, or as part of any dye utilized for pile fabric printing. The nature of the embossing agent dictates the nature of the vehicle to be utilized. Among such applicable vehicles are included: water, and alcohols such as methanol and isopropanol. Often thickeners e.g. gums, are included in order to obtain viscosity characteristics demanded in print technology and to enable the embossing agent to adhere to and operate on the synthetic fiber and to hold the printed pattern.
In those instances where it is desired to achieve a single- or multi-colored printed decoration with a distinct color for the embossed areas, the embossing agent can be incorporated into a particular dye or pigment composition. The dye or pigment will generally be in the form of a print paste ink to which the appropriate amount of agent is added. It is to be noted that in preparing these modified dye compositions, the pH levels, viscosities, and dye concentrations which are essential to an efficient dyeing operation must also be controlled. The resultant effect is an embossed design in register with the printed pattern.
As previously indicated, the preferred embossing agent is one which is dormant during the successive printing operations but then is activated by the elevated temperature of a steam chamber usually utilized to fix the dye onto the fibers. Embossing agents which can function in this manner include chloroacetic acid on nylon fibers. The advantages of this type of embossing agent are that there is no need for rigid time control and there is minimal concern regarding excessive, uncontrollable embossing.
The total amount of embossing agent brought into contact with the fiber will determine in large measure the degree of embossing. Thus, the degree of diminution of the pile height can be controlled by adjusting the amount of dye paste applied, the concentration of embossing agent in the dye and the temperature and time of exposure in the steam chamber. All these factors can be adjusted according to the nature of the fiber comprising the pile fabric. While the depth of embossing will be determined by the practitioner in accordance with the type of embossed product being prepared, reduction in pile height will generally not exceed 50%, the latter value being indicative of excellent embossing without exposing the backing materials.
Depth of penetration and rapidity of action can, if desired, be increased by subjecting the treated fibers to heat for short periods of time. Thus, the treated surfaces may be subjected to the radiation from a bank of infrared lamps, particularly where the embossing agent is not part of a dye print paste. Additionally, even where the steaming operation is not essential to activate the embossing agent, such steaming may have the effect of increasing the penetration of the embossing agent and increasing the speed of its action on the fibers.
The second critical step of the novel process of this invention involves terminating the embossing action and effecting substantial removal of the embossing agent from the pile fabric. The organic acids require actual termination or a degree of removal sufficient to avoid continued attack on the fibers by residual amounts of the embossing agent. It may be necessary to achieve complete elimination of all residues of the embossing process which may contribute undesirable properties to the finished fabric, such as odor, toxicity and color change. Needless to say, any termination or quenching technique resorted to will depend on the particular embossing agent employed. The most expedient technique for removing residues of the embossing process is by thoroughly washing the fabric with water and detergents. In those instances where the embossing agent is part of a dye or pigment composition, the washing cycle which is utilized to remove excess dye or pigment may also be used to remove traces of the agent. With the acidic embossing agents utilized, e.g. chloroacetic acid on nylon, it is possible to halt the embossing action more rapidly by rinsing with an aqueous ammonia or mildly alkaline solution. This neutralization of the acid serves to insure the total removal thereof.
Other techniques for terminating the embossing action and/or removing the embossing agent include evaporation and dry cleaning. Thus, if the agent is volatile, steaming of the treated pile fabric will serve to evaporate a large portion of the embossing agent content. Where rinsing techniques are not effective, it may be necessary to resort to a dry cleaning procedure to remove the embossing residues.
The invention has particular application to tufted carpets which have a printed decoration applied thereon. Unusual design effects can also be obtained when the pile fabric is printed with a multi-colored design wherein one or more of the dye compositions contain the appropriate embossing agent. The process of printing such carpets includes the steps of passing carpets, tufted of unpigmented or color fibers, into a screen printing apparatus whereby a design is printed on the surface of the carpet. Each screen applies a separate color to make up the final design. The proposed embossing agent can be added to one or more of these printing stations by addition to the dye composition, or it can be applied by a separate station in a transparent vehicle. The fabric is then passed into a steaming chamber to set the dyes followed by a washing cycle which serves to remove excess dye as well as to terminate the embossing action and/or remove the embossing components.
The following examples will further illustrate the embodiment of this invention. In these examples, all parts given are by weight unless otherwise noted.
EXAMPLE I
This example illustrates the preparation of an embossed pile fabric typical of the products of this invention.
Sections of a level loop carpet of the following construction were treated by means of screen printing techniques with a dye print paste containing 45 parts of chloroacetic acid embossing agent.
______________________________________Carpet Construction______________________________________Face Weight - 14 oz/sq. yd. 100% NylonMachine Gauge - 5/64Stitch Rate - 13 stitches/in.Pile Height - 1/8"Total Thickness - .310 inches______________________________________
______________________________________Print Paste Parts______________________________________1. Embossing Agent 452. Locust Bean Gum Solution 5% Gum + 5% Benzyl Alcohol 403. Formic Acid 14. Thiodiglycol 55. Dye As Desired6. Water 14______________________________________
Little pile height reduction was noted until the carpet was steamed at 212° F. After steaming for ten minutes at 212° F. the carpet was rinsed, neutralized, given a nonionic scour, rinsed again and dried.
The resulting carpet exhibited an attractive textured surface with a 50% reduction in pile height in the treated areas.
EXAMPLE II
Additional embossed nylon carpets were prepared by means of the general procedure set forth in Example I hereinabove, utilizing the following embossing system.
______________________________________Embossing Agent trifluoroacetic acidPrint Composition 30% trifluoroacetic acid in a dye paste, the composition of which is recited hereinafter.Embossing Conditions steaming at 212° F. for 10 minutes.Results excellent embossing, 50% reduction in pile height.______________________________________
______________________________________Dye Paste Parts______________________________________1. Acidic embossing agent 252. Locust Bean Gum Solution 5% Gum + 5% Benzyl Alcohol 323. Formic Acid 14. Thiodiglycal 55. Dye As Desired6. Water 37______________________________________
A variety of halogenated acetic acid embossing agents and embossing conditions are readily applicable to the novel process of this invention.
Summarizing, it is thus seen that this invention provides a novel and effective method for embossing synthetic pile fabrics.
Variations may be made in procedures, proportions and materials without departing from the scope of the invention as defined in the following claims.
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Pile fabrics prepared from synthetic fibers having a textured or embossed surface resulting from a process which comprises selectively contacting the surface of said fabric with a chemical embossing agent therefor, allowing the embossing action to occur, and thereafter effectively removing the embossing agent from the surface; said embossing serving to reduce the height of the pile in the treated areas and creating said textured appearance.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of pending U.S. patent application Ser. No. 12/823,017, filed on Jun. 24, 2010, entitled “Meta-Web”, which is a continuation application of U.S. patent application Ser. No. 10/737,618, filed on Dec. 15, 2003, entitled “Meta-Web”, and issued as U.S. Pat. No. 7,765,206, issued on Jul. 27, 2010, which is a continuation-in-part of U.S. patent application Ser. No. 10/474,155, filed Apr. 10, 2002, entitled “Knowledge Web”, and issued as U.S. Pat. No. 7,502,770, issued on Mar. 10, 2009 and claims priority to U.S. Provisional Patent Application No. 60/529,245, filed Dec. 12, 2003, entitled “Reputation System”, and U.S. Provisional Patent Application No. 60/433,050, filed Dec. 13, 2002, entitled “Automated Purchasing System/Multi-player Game Hub with Voting Scheme”. The disclosures of the foregoing applications are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The invention relates to knowledge. More particularly, the invention relates to a system for organizing knowledge in such a way that users can find it, learn from it, and add to it as needed.
[0004] 2. Description of the Prior Art
[0005] There is widespread agreement that the amount of knowledge in the world is growing so fast that even experts have trouble keeping up. Today not even the most highly trained professionals—in areas as diverse as science, medicine, law, and engineering—can hope to have more than a general overview of what is known. They spend a large percentage of their time keeping up on the latest information, and often specialize in highly narrow sub-fields because they find it impossible to keep track of broader developments.
[0006] Education traditionally meant the acquisition of the knowledge people needed for their working lives. Today, however, a college education can only provide an overview of knowledge in a specialized area, and a set of skills for learning new things as the need arises. Professionals need new tools that allow them to access new knowledge as they need it.
The World Wide Web
[0007] In spite of this explosion of knowledge, mechanisms for distributing it have remained pretty much the same for centuries: personal communication, schools, journals, and books. The World Wide Web is the one major new element in the landscape. It has fundamentally changed how knowledge is shared, and has given us a hint of what is possible. Its most important attribute is that it is accessible—it has made it possible for people to not only learn from materials that have now been made available to them, but also to easily contribute to the knowledge of the world in their turn. As a result, the Web's chief feature now is people exuberantly sharing their knowledge.
[0008] The Web also affords a new form of communication. Those who grew up with hypertext, or have otherwise become accustomed to it, find the linear arrangement of textbooks and articles confining and inconvenient. In this respect, the Web is clearly better than conventional text.
[0009] The Web, however, is lacking in many respects.
[0010] It has no mechanism for the vetting of knowledge. There is a lot of information on the Web, but very little guidance as to what is useful or even correct.
[0011] There are no good mechanisms for organizing the knowledge in a manner that helps users find the right information for them at any time. Access to the (often inconsistent or incorrect) knowledge on the Web thus is often through search engines, which are all fundamentally based on key word or vocabulary techniques. The documents found by a search engine are likely to be irrelevant, redundant, and often just plain wrong.
[0012] The Web knows very little about the user (except maybe a credit card number). It has no model of how the user learns, or what he does and does not know—or, for that matter, what it does and does not know.
A Comparison of Knowledge Sources
[0013] There are several aspects to how learners obtain knowledge—they might look at how authoritative the source is, for example, or how recent the information is, or they might want the ability to ask the author a question or to post a comment. Those with knowledge to share might prefer a simple way to publish that knowledge, or they might seek out a well-known publisher to maintain their authority.
[0014] While books and journals offer the authority that comes with editors and reviewers, as well as the permanence of a durable product, the Web and newsgroups provide immediacy and currency, as well as the ability to publish without the bother of an editorial process. Table “A” is a summary of the affordances of various forms of publishing.
[0000]
TABLE A
Affordances of Various Forms of Publishing
News
Text
The Web
Groups
Books
Journals
Peer-to-Peer
Yes
Yes
No
Limited
publishing
Supports
Yes
Limited
No
Limited
linking
Ability to add
No
Yes
No
No
annotations
Vetting and
No
Limited
Yes
Yes
certification
Supports
Limited
No
Yes
Yes
payment model
Supports
Limited
No
Yes
No
guided learning
Corporate and Government Needs
[0015] For institutions, corporations, and governments, failure to keep track of knowledge has consequences that are quite different from those for an individual. Often, institutions make a bad decision due to lack of knowledge on the part of those at the right place and at the right time, even though someone else within the institution may actually hold the relevant knowledge.
[0016] Similarly, within a corporation, the process of filtering and abstracting knowledge as it moves through the hierarchy often leaves the decision-maker (whether the CEO, the design engineer, or the corporate lawyer) in a position of deciding without the benefit of the best information. The institutional problem is made worse by the problem of higher employee turnover in the more fluid job market, so that the traditional depository of knowledge—long-standing employees—is beginning to evaporate, just as the amount of knowledge that needs to be kept track of is exploding.
[0017] The consequences of not having the right knowledge at the right place and time can be very severe: doctors prescribing treatments that are sub-optimal, engineers designing products without the benefit of the latest technical ideas, business executives making incorrect strategic decisions, lawyers making decisions without knowledge of relevant precedents or laws, and scientists working diligently to rediscover things that are already known—all these carry tremendous costs to society.
[0018] The invention addresses the problem of providing a system that has a very large, e.g. multi-petabyte, database of knowledge to a very large number of diverse users, which include both human beings and automated processes. There are many aspects of this problem that are significant challenges. Managing a very large database is one of them. Connecting related data objects is another. Providing a mechanism for creating and retrieving metadata about a data object is a third.
[0019] In the past, various approaches have been used to solve different parts of this problem. The World Wide Web, for example, is an attempt to provide a very large database to a very large number of users. However, it fails to provide reliability or data security, and provides only a limited amount of metadata, and only in some cases. Large relational database systems tackle the problem of reliability and security very well, but are lacking in the ability to support diverse data and diverse users, as well as in metadata support.
[0020] The ideal system should permit the diverse databases that exist today to continue to function, while supporting the development of new data. It should permit a large, diverse set of users to access this data, and to annotate it and otherwise add to it through various types of metadata. Users should be able to obtain a view of the data that is complete, comprehensive, valid, and enhanced based on the metadata.
[0021] The system should support data integrity, redundancy, availability, scalability, ease of use, personalization, feedback, controlled access, and multiple data formats. The system must accommodate diverse data and diverse metadata, in addition to diverse user types. The access control system must be sufficiently flexible to give different users access to different portions of the database, with distributed management of the access control. Flexible administration must allow portions of the database to be maintained independently, and must allow for new features to be added to the system as it grows.
[0022] It would be advantageous to provide a system to organize knowledge in such a way that users can find it, learn from it, and add to it as needed.
SUMMARY OF THE INVENTION
[0023] In a preferred embodiment, the invention dynamically generates content and presentations for a user by modifying conventional content, e.g. rendering, restructuring, filtering, or supplementing such content, based on information, e.g. annotations, stored in a database. The invention, referred to as the Meta-Web, allows a user at a Web browser, which may be any standard Web browser supported by a standard computing platform, posits a query that is routed to a Meta-Web server. The Meta-Web server routes the query to a search engine that returns search results to the Meta-Web server. The Meta-Web server then routes the results to a Meta-Web registry that, based on the search results and the content of the registry returns annotations and other meta-data to the Meta-Web server. The Meta-Web server uses the annotations and/or other meta-data to generate and route annotated pages to the browser and the user may then explore the results within the annotated pages, for example by clicking on a URL within the annotated pages.
[0024] Unique to the invention is the provision of the registry that receives the search results and provides annotations and/or other information to the Meta-Web server. The registry may also accumulate knowledge, meta-knowledge that was created at a time of entry of such knowledge, and meta-knowledge in the form of one or more annotations that accumulate over time, where the annotations include any of, but are not limited to, usefulness of said knowledge, additional user opinions, certifications of veracity of said knowledge, reputation (which may be based on a formal reputation system), commentary by users, and connections between the knowledge and other units of knowledge.
[0025] To create the annotated pages, the Meta-Web server either combines both the search results and information from the registry, or operates upon the search results in accordance with information contained in the registry. The search results are thus augmented or modified by the registry information under control of the Meta-Web server, which then builds the annotated pages. The annotated pages are then forwarded to the user's Web browser.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a block schematic diagram showing the architecture of the Meta-Web facility according to the invention;
[0027] FIG. 2 is a display showing a subject field which includes a portion into which the user may enter a search query according to the invention;
[0028] FIG. 3 is a display showing the results provided to the user in response to the query of FIG. 2 according to the invention;
[0029] FIG. 4 is a display showing a pop-up window which provides information regarding the relevancy to the user of the search results of FIG. 3 according to the invention;
[0030] FIG. 5 is a display showing a pop-up window which shows relevancy of the search results by indicating that the search results include something of personal interest to the user according to the invention;
[0031] FIG. 6 is a display in which the user has selected one of the search results from the list of results of FIG. 3 according to the invention;
[0032] FIG. 7 is a display showing a pop-up window that provides answers to Frequently Asked Questions according to the invention;
[0033] FIG. 8 is a display showing the user has selected the related items button for the portion of text that is highlighted by the user according to the invention;
[0034] FIG. 9 is a display showing the user selecting only the documents in the related items and info window according to the invention;
[0035] FIG. 10 is a display showing the selected document displayed with its own annotations according to the invention;
[0036] FIG. 11 is a display showing a pop-up window that provides information of interest to the user according to the invention;
[0037] FIG. 12 is a display showing a comment window according to the invention;
[0038] FIG. 13 is a display showing a pop-up window that allows the user to look at information that has been obtained from diverse sources about a product according to the invention;
[0039] FIG. 14 is a display that shows that the user has selected a related items icon according to the invention;
[0040] FIG. 15 is a display that shows a Meta-Web object according to the invention;
[0041] FIG. 16 is a display that shows a “change my window” button that allows the user to change the appearance of the information according to the invention;
[0042] FIG. 17 is a display that shows a manufacturer's specification sheet which is displayed when the user selects a manufacturer specifications sheet button according to the invention;
[0043] FIG. 18 is a display which shows that the user has selected the buy button and can enter a personalized purchase transaction to bring the user to a preferred vendor according to the invention;
[0044] FIG. 19 is a display which shows an information-seeking problem where the user is looking to find information about a more complex product or service according to the invention;
[0045] FIG. 20 is a display which is similar to that shown in FIG. 3 , except that in this case the results relate to the user's query with regard to relevance to the user according to the invention;
[0046] FIG. 21 is a display which shows the user choosing the first document in the results set according to the invention;
[0047] FIG. 22 is a display which shows an article selected by the user from a list of results according to the invention;
[0048] FIG. 23 is a display which shows the selected document, where the user is not interested in the result according to the invention;
[0049] FIG. 24 is a display which shows the user selects a first document according to the invention;
[0050] FIG. 25 is a display which shows the selected document displayed according to the invention;
[0051] FIG. 26 is a display which shows the user has scrolled to the end of the selected document according to the invention;
[0052] FIG. 27 is a display which shows the user selecting the comment button according to the invention;
[0053] FIG. 28 is a display which shows a pop-up window that is spawned to ask the user to select the text that would be associated with a comment according to the invention;
[0054] FIG. 29 is a display which shows the user selecting text according to the invention;
[0055] FIG. 30 is a display which shows the user entering a comment according to the invention;
[0056] FIG. 31 is a display which shows the user submitting a comment to the Meta-Web server by selecting a submit button according to the invention;
[0057] FIG. 32 is a display which shows the comment icon highlighted to show that there is a comment of personal interest to the user according to the invention;
[0058] FIG. 33 is a display which shows the user is about ask to a question related to the document according to the invention;
[0059] FIG. 34 is a display which shows the user is informed that the question with be forwarded to the author according to the invention;
[0060] FIG. 35 is a display which shows a user selecting the ask button, where the Meta-Web server spawns an ask window into which the user may enter a question according to the invention;
[0061] FIG. 36 is a display which shows the user selecting the buy button according to the invention;
[0062] FIG. 37 is a display which shows the user selecting another buy button according to the invention;
[0063] FIG. 38 is a display which shows a list of vendors according to the invention;
[0064] FIG. 39 is a display which shows that some icons appear darker while others appear lighter according to the invention;
[0065] FIG. 40 is a display which shows the user selecting the personal interest icon according to the invention;
[0066] FIG. 41 is a display which shows a list of vendors, with indication that several of the vendors have associated web sites according to the invention; and
[0067] FIG. 42 is a display which shows the vendor's Web site according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0068] FIG. 1 is a block schematic diagram showing the architecture of the Meta-Web facility disclosed herein. In operation, a user at a Web browser 10 , which may be any standard Web browser supported by a standard computing platform, posits a query ( 1000 ) that is routed to a Meta-Web server 16 . The Meta-Web server routes the query ( 1006 ) to a search engine that returns search results ( 1008 ) to the Meta-Web server. The Meta-Web server then routes the results ( 1010 ) to a Meta-Web registry ( 14 ) that, based on the search results and the content of the registry returns annotations and/or other meta-data ( 1012 ) to the Meta-Web server. The Meta-Web uses the annotations and/or other meta-data to generate and route annotated pages ( 1014 ) to the browser, and the user may then explore the results within the annotated pages, for example by clicking on a URL within the annotated pages ( 1004 ).
[0069] Unique to the invention is the provision of the registry 14 that receives the search results ( 1010 ) and provides annotations ( 1012 ) and/or other information to the Meta-Web server. The registry may also accumulate knowledge, meta-knowledge that was created at a time of entry of such knowledge, and meta-knowledge in the form of one or more annotations that accumulate over time, where the annotations include any of, but are not limited to, usefulness of said knowledge, additional user opinions, certifications of veracity of said knowledge, reputation (which may be based on a formal reputation system), commentary by users, and connections between the knowledge and other units of knowledge. Such connections comprise typed links between registry objects, where such links may comprise, for example, relationships, such as a person's role in an organization or a place where a person lives, and such objects may comprise, for example, representations of products, people, places, categories, events, organizations, roles, documents, portions of documents, certifications, ratings, dates, and times.
[0070] To create the annotated pages, the Meta-Web server either combines both the search results and information from the registry, or operates upon the search results in accordance with information contained in the registry. The search results are thus augmented or modified by the registry information under control of the Meta-Web server, which then builds the annotated pages. The annotated pages are then forwarded to the user's Web browser.
[0071] Accordingly, the presently preferred embodiment of the invention comprises four elements, i.e. a standard Web browser and a standard search engine, which are well known to those skilled in the art, and the registry and Meta-Web server. The registry associates metadata with objects, while the Meta-Web server creates Web pages dynamically, which are then sent to the user's Web browser for viewing by the user. While a Web browser is described herein in connection with the presently preferred embodiment, those skilled in the art will appreciate that other access facilities may be used to practice the invention. As well, the search engine may comprise any type of data access facility. Key to the invention is the provision of the Meta-Web server and registry. Further, while the Meta-Web server and registry are discussed herein as separate elements, their functionality may be combined into a single element. Likewise, their functionality may be dispersed broadly across several elements. For example, a knowledge base comprising knowledge, meta-knowledge that was created at a time of entry of said knowledge, and meta-knowledge in the form of one or more annotations that accumulate over time, the annotations including any of, but not limited to, usefulness of said knowledge, additional user opinions, certifications of veracity of said knowledge, commentary by users, and connections between said knowledge and other units of knowledge may comprise an element of the invention, see U.S. patent application Ser. No. 10/474,155, filed 10 Apr. 2002.
[0072] The Meta-Web server as presently embodied creates two types of Web pages, both of which are described in the discussion below and in the Figures accompanying that discussion. One of the Web pages is a Web page that consists of search results with annotations. The other type of Web page is a Web page that consists of a content page with an annotation tool, such as an annotation bar at the side of the results page. In the preferred embodiment, the annotation bar is incorporated into a standard Web browser, but in other embodiments it may be part of a separate Meta-Web application which runs on the user's computer, or it may be an element that is spawned by operation of the user's Web browser, such as a Java applet or JavaScript.
[0073] Content displayed to the user is dynamically extracted from the registry by the Meta-Web server. Known techniques for displaying this information include framing, HTML, cascading style sheets, and the like. As discussed in detail below, the architecture herein disclosed provides annotations, search results, and other information in a standard Web browser, as well as a suite of tools for interacting therewith.
[0074] The Meta-Web server constructs a search query page which includes a field into which a user can enter one or more search terms. Standard searching techniques, such as Boolean operations, are supported. The query page is delivered to the user's Web browser as a search form. The search form may resemble well known search forms, such as those provided by Google® or it may be presented in any other appropriate format.
[0075] When the user enters a query into the search form, the query is forwarded to the search engine by the Meta-Web server. In the preferred embodiment, a user query is processed by the Meta-Web server. Thus, a Web page is constructed by the Meta-Web Server in response to the query when a query is directed to the Meta-Web server from the user via the user's Web browser. Rather than providing results from the search engine directly to the user, the Meta-Web server examines the search results and then performs a look-up in the registry to determine if there are annotations or other information associated with the search results that might be used, for example, to order the results in terms of relevance or other orderings. Likewise, the Meta-Web server may consult the registry prior to positing the query to the search engine. The Meta-Web server may then modify the query or search space and, thereafter, submit the query to the search engine.
[0076] Any annotations or other metadata found in the registry may be added to the search results. The Meta-Web server then dynamically constructs a presentation for the user which is returned to the user. The form of the presentation may be controlled by a preference set by the user in the user's Web browser, based upon a user profile stored in the registry, or any combination thereof.
[0077] Metadata may be used by the Meta-Web server to check a query term in the registry and determine if there is a prepared way of presenting the data in connection with the term. For example, if there is a common term, it may be determined that the registry has a standard presentation or query results for that term, and that that presentation is preferred over other presentations. Thus, as an alternative to dynamic assembly of the Web page, the registry may provide the Meta-Web server with a preformed response for the query.
[0078] One embodiment of the invention provides a relevance button that may be displayed to the user to create a display item which explains the relevance of a term.
[0079] In another embodiment, the user may select an item and instead of returning the Web page to the user, that aspect of the search would be framed in the Web page with an annotation bar as discussed above. Thus, the Meta-Web server adds the annotation bar to the Web page to provide the user with the ability not only to comment on relevance or usability of the search result, but to add annotations as desired. Such annotations are then stored in the registry for further use. The annotations are thereafter linked to that user's search space so that further queries by the user bring up the annotations. Further, the annotations may be linked for all uses of that term so that queries by other individuals also produce the annotations entered by the user through the annotation bar. In this way, a community of annotations is assembled which is associated with a particular query term or search result. These aspects of the invention are discussed in greater detail below.
[0080] Thus, the presently preferred embodiment of the invention provides selected content within a frame and provides additional frames for annotations, as well as a tool bar for entering and editing annotations. The Meta-Web server dynamically creates the frame for this page and collects the content and annotations to create the complete page. In another embodiment, HTML or XML may be used to accomplish a similar purpose. Additionally, the Meta-Web server may incorporate active components, such as JavaScript or Java applets to provide additional functionality to the user during the annotation process, and may also employ cascading style sheets.
[0081] If the content selected by a user relates to a product, i.e. the URL selected by the user leads to a product node, then the Meta-Web server can perform an independent search to collect data with regard to that particular product and dynamically create a Web page for the user that includes information collected in real time. Alternatively, the additional information may be associated with the product in the registry and the Meta-Web server associates the registry information with the product.
[0082] Various schemes are envisioned by which the registry, under direction of the Meta-Web server, may be independently updated to refresh or enhance this information. For example, a particular product may be the subject of additional independent searching under control of the Meta-Web server when a certain number of requests are made for a particular product, or when a particular interval has elapsed since the last query concerning the product. Further, independent events, such as discontinuation of a product, may trigger Meta-Web server activities.
[0083] The Meta-Web server may identify products within a Web page provided to a user as a result of a user's request for content. Thus, the Meta-Web server identifies product terms or other terms in a page of content, for example by highlighting or underlining, indicating that additional information is available to the user for those products or terms. For example, the user may be performing a search for a particular class of products and within the content a particular product is mentioned. If that product is highlighted, then the user is made aware that the Meta-Web server has identified related information in the registry. The user may then select that highlighted term and the information in the registry is then provided to the user.
[0084] For example, if the name of a product is identified, a product node may be selected and annotations associated with it may be provided to the user. Further, the Meta-Web server may provide a filter for those annotations to determine which annotations are of interest to the user, depending on the user profile or user preferences. These annotations can include offers by various merchants to sell the product and other information that may be of interest in connection with the product.
[0085] In the event of a filter being applied, the filter may be based on a user profile that may be stored in one of several places. For example, a Web site visited by the user could store a cookie related to the user. In this case, the user could automatically be logged in to the Meta-Web server or at a site being visited, all as a result of a cookie. The Meta-Web server could also keep a profile of the user in a separate database or it could use the registry database. The profile itself may comprise, for example, trusted reputation systems (see, for example, U.S. Provisional Patent Application entitled “Reputation System,” Attorney Docket No. APPL007CI2PR, filed Dec. 12, 2003, U.S. Serial No. not yet assigned), preferred vendors and areas of specific user competence, interest, or understanding.
[0086] In FIG. 2 , a subject field 20 is provided which includes a portion into which the user may enter a search query. When the user has finished composing the query, the user may select the find button 22 , and the query is then passed to the Meta-Web server where it is executed.
[0087] The invention, also includes an annotation bar 21 , as discussed above, which is dynamically added to any content, such as search results, that is served to the user by the Meta-Web server. The annotation bar may include user-actuated buttons which provide such functions as allowing the user to comment 24 , ask questions 26 , indicate that the information is relevant 27 , or indicate that the information is not relevant 28 . Such buttons may be, for example, special local tools embedded in a browser or part of a separate local tool application, or, they may be incorporated into a modified results page.
[0088] The invention is envisioned as having many applications. One application of the invention concerns a product purchase, where the user is looking to buy a product on-line after getting information about it. In this example, the user types in a search expression in the subject field 20 . In the example of FIG. 2 , the user is looking for information on a flat screen TV.
[0089] FIG. 3 is a screen shot showing the results provided to the user in response to the query for a flat screen TV. The results are sorted in a way that is personalized for the user. Thus, various icons may be provided near the results. As shown in FIG. 3 , the entry “Television Shopping Review/Video/TV & HDTV” is accompanied by an icon 31 that appears in FIG. 3 to be darker, while the entry “Net-TV vs. Sony Panasonic digital flat screen TV's pure plasma” is accompanied by an icon 32 that appears to be lighter. The significance of the various icons is discussed below. If the user selects the darker icon 31 , then a pop-up window 40 provides information regarding the relevancy to the user of the search result, as shown in FIG. 4 .
[0090] As shown in FIG. 5 , if the lighter icon is selected, then a pop-up window 50 also shows relevancy of the search result, but the lighter color indicates that the search results include something of personal interest to the user, such as an endorsement by a personal friend. This can be seen in the pop-up window 50 where it is indicated that the document was recommended because “Stewart Brand likes it.” In this example, Stewart Brand is a friend of the user. The assembly of the information into this format is performed by the Meta-Web server based upon the combining of information contained in the registry and the search results, as described above.
[0091] While the examples herein show icons which indicate relevancy by having lighter or darker intensity, the context of indication provided by the icons and the constituency of the icons is a matter of choice for those skilled in the art. Thus, the icons may flash, may be of different colors, may of different shapes, and the like. Further, a user may be alerted by device other than icons, such as audible beeps, and the like.
[0092] FIG. 6 is a screen shot in which the user has selected one of the search results 60 from the list of results 30 , see FIG. 3 . Various gray icons 61 are shown at the right hand side of the display. The upper icons refer to the entire document and include relevancy 62 , information 63 , and buy 64 . The bottom icons relate to a portion of the document, for example a user highlighted portion of the document, and include the availability of FAQs 65 , additional information 66 , and an option to buy 67 the product.
[0093] In FIG. 7 , the user has selected the FAQs button 65 and a pop-up window 70 provides answers to Frequently Asked Questions. The FAQs associated with the document concern that part of the document which is highlighted by the user 71 . Thus, the invention contemplates that the user can select portions of documents, which are then used by the Meta-Web server to identify annotations in the registry and dynamically generate FAQs relating thereto. Highlighting may also be accomplished automatically by the Meta-Web server, for example, in response to a user query, where the query terms are used to highlight relevant portion of a document.
[0094] In FIG. 8 , the user has selected the related items button 66 for the portion of text 80 that is highlighted by the user. As a result, a pop-up window 81 provides related items and information for the highlighted text. As above, this information is assembled dynamically by the Meta-Web server in connection with the registry.
[0095] In FIG. 9 , the user selects only the documents 91 in the related items and info window 81 .
[0096] In FIG. 10 , selected document 100 is displayed with its own annotations. Each document has a unique set of annotations. In the example of FIG. 10 , the relevancy icon 62 is illuminated to indicate that there is a comment of personal value or interest to the user.
[0097] In FIG. 11 , the user has selected the relevancy icon 62 and a pop-up window 110 provides the information of interest to the user. In this case, a window “about this document” is spawned that provides various data gathered from diverse sources that are relevant to the user.
[0098] In FIG. 12 , the user has highlighted the product “Panasonic PT-45LC12,” as shown by the box 157 which surrounds the product name. The user has also selected a comment icon 120 which spawns a comment window 121 for the selected product. In this case, a message from a personal friend is displayed. The comment is associated with a product name. Note that the friend in this case has annotated the product but not the particular document that the user is currently viewing. Here, the Meta-Web server has linked Stewart Brand's comment about the product to the product itself, and it has linked the product to the document, as well as to Stewart Brand and to the current user, to display the annotation shown. Thus, various connections have been formed by the Meta-Web server based on the personal information of the user and other information, all of which reside in the registry or within the realm of resources available to the Meta-Web server.
[0099] In FIG. 13 , the user has selected an information icon 130 which spawns a pop-up window 131 that allows the user to look at information about the product that has been obtained from diverse sources.
[0100] In FIG. 14 , the user has selected a related items icon 66 . The Meta-Web server then spawns a related items window 140 in which the user finds a product node for the user highlighted product, as discussed above. The product node is an abstract Meta-Web object that is constructed by the Meta-Web out of all the information relating to the product. In this case, the node is a ranked list of information.
[0101] As shown in FIG. 15 , the user selects the item <Product Node: Panasonic PT-45LC12> 156 from the related items window.
[0102] FIG. 16 is a display that shows a Meta-Web object 150 which is a representation of a product node that is dynamically created by the Meta-Web to group together all the information relating to a product. In the example of FIG. 15 , the user interface had been tailored for a particular user through user profile and preference information. Those skilled in the art will appreciate that any of standard and personal formats may be provided for the display. In the example of FIG. 16 , a “change my window” button 151 is provided to allow the user to change the appearance of the information. By selecting the “change my window” button the user's “my window” presentation 152 may be changed.
[0103] If the user selects the manufacturer specifications sheet button 153 , the manufacturer's specification sheet 162 is displayed (see FIG. 17 ). The annotations discussed above are associated with the manufacturers specifications sheet as well.
[0104] In FIG. 18 , the user has selected the buy button 64 and can enter into a personalized purchase transaction to bring the user to a preferred vendor or list of vendors. In various embodiments in the invention, the user's wallet or other personal information may be linked to the Meta-Web server such that the user's purchase transaction may proceed in an automated fashion.
[0105] A further example of the invention is concerned with an information-seeking problem where the user is looking to find information about a more complex product or service. In this example (see FIG. 19 ) the user is interested in LASIK eye surgery and enters that term into the search field 20 .
[0106] As shown in FIG. 20 , a screen similar to that shown in FIG. 3 , described above, is assembled by the Meta-Web server and returned to the user, except in this case the results 190 relate to the user's query with regard to LASIK and the results have been ordered with regard to relevance to the user.
[0107] As shown in FIG. 21 , the user chooses the first document 200 in the results set. The selected document 210 , see FIG. 22 , turns out to be a technical paper on eye surgery, but the user is not interested in this result. Rather than go back to the results screen, the user selects the “Don't like it” button 28 , see FIG. 23 . This action updates the user's profile via the Meta-Web server and takes the user back to the results screen, see FIG. 24 . The Meta-Web server has used the updated user profile in this case to re-write the result list 198 . Accordingly, the user now sees a different results screen with documents that are more likely to be useful. The user selects the first document 230 ( FIG. 25 ). The selected document 240 (see FIG. 26 ) is displayed. Note that there are annotations available for the document as indicated by the icons at the right side of the document.
[0108] As shown on FIG. 27 , the user has scrolled to the end 250 of the selected document 240 . The user selects the comment button 24 ( FIG. 28 ). This allows the user to add a comment to the document. A pop-up window ( FIG. 29 ) is spawned to ask the user to select the text which comprises an excerpt of the document that is to be associated with his comment. As shown in FIG. 30 , the user selects the text document indicated by drawing a box 280 around the text. The user then enters his comment 290 ( FIG. 31 ). Next, the user submits his comment to the Meta-Web server by selecting a submit button 300 ( FIG. 32 ) and the registry is updated to include the user comments. The comment icon 120 is now highlighted to show that a comment of personal interest has been entered by the user ( FIG. 33 ).
[0109] In FIG. 34 , the user is about to ask a question related to the document. In this case, the user selects the ask button 26 . The user is informed that the question with be forwarded to the author 331 ( FIG. 35 ). Other documents may have different mechanisms for dealing with questions, in addition to forwarding the question to the author.
[0110] By selecting the ask button 26 , the Meta-Web server spawns an ask window 330 into which the user may enter his question ( FIG. 36 ). The user asks his question 340 and submits it to the Meta-Web server by selecting the ask button 341 .
[0111] As shown in FIG. 37 , the user selects the buy button 64 and the Ray-Ban Ad 350 on the left side of the display is highlighted. The user is not interested in sun glasses, so he makes another choice.
[0112] As shown in FIG. 38 , the user selects another buy button 360 and the word LASIK 361 in the text is highlighted. Because the user is interested in LASIK, rather than Ray-Ban, the user selects the buy button associated with LASIK. Thus, multiple instances of buy buttons and other buttons may be presented to the user on the right hand side to help the user judge the relevancy of the particular portion of the document. The user's choice in selecting LASIK is recorded in the registry by the Meta-Web server and this information may be used in the future to provide more relevant information to the user and/or to groups of users.
[0113] As a result of selecting the buy button 360 , the user is presented with a list of vendors 370 ( FIG. 39 ). The list of the vendors is a results screen that is sorted in a personalized way. As with other result screens, the relevancy of the results are displayed by various types of icons. In FIG. 39 , some icons appear darker while others appear lighter.
[0114] As shown in FIG. 40 , the user selects the personal interest icon 380 . In this example the Meta-Web server has brought together a number of pieces of information to make its recommendation. As shown in the relevancy window 381 , the vendor is “Maloney Vision Institute,” Dr. Maloney is associated with the vendor, Dr. Maloney is rated highly by Dr. Szabo, and Dr. Szabo is rated highly by the user and his personal physician. Also indicated is that the vendor is covered under the user's medical insurance provider.
[0115] As shown in FIG. 41 , the vendor has an associated Web site 390 and the user selects the Web site. As a result, the vendor's Web site 400 is displayed to the user, see FIG. 42 .
[0116] Although the invention is described herein with reference to the preferred embodiment, one skilled in the art will readily appreciate that other applications may be substituted for those set forth herein without departing from the spirit and scope of the present invention. Accordingly, the invention should only be limited by the Claims included below.
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In one aspect, a system includes an information server, operable to perform operations comprising: receiving a search query from a user device; receiving search results responsive to the search query from a search engine; determining from a registry that user annotations or other metadata are associated with the received search results; ordering the search results according to their relevance, where the relevance is determined based at least in part on the user annotations or other metadata in the registry; generating a search results page including the ordered search results and an annotation tool, wherein the annotation tool provides functions that allow a user of the user device to provide annotations for a particular search result, and wherein the annotation tool receives annotations provided by the user for later use in generating search results pages; and transmitting the search results page to the user device for presentation.
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PRIORITY
This application is a non-provisional application and claims priority from, the provisional patent application having Ser. No. 60/633,279, filed Dec. 3, 2004, entitled “ENVIRONMENTALLY FRIENDLY SOLID LUBRICANT STICKS.” This application is also a continuation-in-part of and claims priority from the divisional patent application entitled SOLID LUBRICANT AND COMPOSITION filed by Michael J. Mitrovich on Sep. 3, 2003 with Ser. No. 10/655,082 now abandoned, which claims priority from the issued utility patent application Ser. No.10/123,001, filed Apr. 11, 2002 entitled Solid Lubricant and Composition filed by Michael J. Mitrovich, issued on Nov. 18, 2003 with Registration Number 6,649,573, both of which claimed priority from the provisional application entitled Solid Lubricant and Composition filed by Michael J. Mitrovich on Apr. 13, 2001, having Ser. No. 60/283,869, the disclosures of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to stick lubricants and more particularly relates to natural based stick lubricants for railroad applications.
2. Background Information
For over fifty years heavy haul railroads have used a variety of methods to reduce friction between the locomotive/railcar wheel flanges and the gauge face of the rail with which it comes in contact. Railroads and transits have realized they can save substantial amounts of money in lowered maintenance and equipment replacements if lubrication is applied.
Several methods have been used including one method wherein hundreds of wayside lubricators eject hydrocarbon petroleum based lubricants onto the gauge face of the rail as the train travels through a curve. A second method for applying lubricant has been to use track inspection trucks to spray petroleum or synthetic grease onto the gauge face of the track as the inspection truck goes through a curve. A third method is to apply lubricant to the wheel flange of the locomotive whereupon the lubricant gets transferred from the wheel flange of the locomotive to the wheel flange of railcars. Lubricant is then passed back through the train as successive wheels come in contact with the rail and pick up some of the lubricant.
These types of lubrication are typically accomplished by spray devices that squirt small amounts of lubricating oil onto wheel flanges. There are inherent problems with the above-described methods of applying lubricant. First, sprayed oil has a tendency to migrate to the tread of the wheel, making it more difficult for the train to stop. Also, grease and oil on top of the rail can cause the train wheels to slip, inhibiting the ability of the brakes of the train to slow or stop the train. In addition, grease and oil on top of the rail can make it difficult for the train to gain traction from a stopped position or when climbing an incline. Secondly, to keep oil spray devices in working order, it requires excessive maintenance time and expense.
An alternative method for overcoming problems with spraying oil onto the wheel flange of the locomotive or railcar has been to use a solid lubricant stick or rod. The stick or rod is inserted into a tube that is then applied by various mechanical means to the flanges of the wheel of a locomotive or railcar via friction.
Prior art solid lubricants also have inherent problems. First, prior art lubricant sticks contain graphite or molybdenum powders because of their anti-wear properties. These prior art molybdenum disulfide compound sticks were made without polymers whereby the molybdenum disulfide was smashed together in a foil wrapper. However, this made the lubricant stick very hard and brittle, so that they could not withstand a rugged locomotive or railcar environment and the sticks would break or disappear.
Prior art solid lubricant stick compositions also have used polymeric carriers to provide durability, but have also included materials that do not provide extreme pressure anti-wear protection or are potentially hazardous to the environment. In some prior art, the sticks have promoted the ability to lubricate a particular wheel flange, but because they have not contained additives to withstand the extreme pressure of a locomotive or railcar flange against the track, the lubricant has not transferred throughout the train. In other prior art, the solid lubricant has lubricated throughout the train, but these formulas contain undesirable hazardous metallic powders, because of their anti-wear capabilities, but the metallic powders not only pollute the environment, but also may be hazardous to railroad workers.
In other prior art sticks, the lubricant is embedded within a polymeric carrier (typically a petroleum based polymer such as polyethylene), this polymeric carrier stick pressed against the wheel flange for wearing off and application of lubricant there-to. An example of such a lubricant stick is Applicant's patent (U.S. Pat. No. 6,649,573) for a solid lubricant and composition.
Other prior art patents include the following. U.S. Pat. No. 3,537,819 to Davis, et al., discloses that the characteristics of the solid lubricant such as hardness, deposition and rigidity are dependant on the molecular weight and the amount of high molecular weight polyethylene that is used. U.S. Pat. No. 3,541,011 to Davis, et al., also discloses a solid lubricant whereby the characteristics of the lubricant such as hardness, deposition and rigidity are dependent on the molecular weight and on the amount used of high molecular weight polyethylene. U.S. Pat. No. 3,729,415 to Davis, et al., discloses a combination of polyethylene and hydrocarbon oil in a stick lubricant that does not contain extreme anti-wear materials to prevent excessive wear. U.S. Pat. No. 4,915,856 to Jamison discloses an alternative solid polymeric stick formula, which includes lead and other metallic powder in either single or co-extruded compositions. While the metallic powder offers anti-wear properties, it also can pollute the environment, such as ground water, when it drops alongside and also can present hazardous conditions for rail workers. Inclusion of metallic powders, which may be considered hazardous by the E.P.A., is undesirable to railroads and transits.
Still other advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description wherein I have shown and described only the preferred embodiment of the invention, simply by way of illustration of the best mode contemplated by carrying out my invention. As will be realized, the invention is capable of modification in various obvious respects all without departing from the invention. Accordingly, the description of the preferred embodiment is to be regarded as illustrative in nature, and not as restrictive.
SUMMARY OF THE INVENTION
In order to overcome problems inherent in the prior art there has been devised by the present invention a more environmentally friendly solid lubricant and composition useful for lubricating the flanges of locomotive wheels, railcar wheels, rail tracks, and in applications where it is desirable to reduce friction when metal contacts metal.
A first embodiment of a solid lubricant of the present invention comprises from about 15% to about 70% by volume of a polymeric carrier, 10% to 15% by volume of cornstarch or other complex carbohydrate, 5% to 75% percent by volume of organic and inorganic extreme pressure additives (preferably including an organic and inorganic powder lubricant), optionally a synthetic extreme pressure anti-wear liquid oil, and optionally an optical brightener so that the lubricant can be seen under black light conditions to allow verification that the lubricant is coating the surface to which it is applied.
In a second preferred embodiment of the present invention, the stick lubricant comprises from about 20% to about 70% by volume of at least one polymeric carrier (preferably a polylactic acid-based polymer such as polyactide (PLA)); from about 5% to about 75% by volume of at least one lubricant powder; from about 0% to about 20% by volume of at least one synthetic extreme pressure anti-wear liquid oil; and from about 0% to about 1% by volume of an optical brightener.
Still other advantages and formulations of the present invention will become readily apparent to those skilled in this art from the following detailed description wherein I have shown and described only the preferred embodiment of the present invention, simply by way of illustration of the best mode contemplated by carrying out my invention. As will be realized, the invention is capable of modification in various obvious respects all without departing from the invention. Accordingly, the description of the preferred embodiment is to be regarded as illustrative in nature, and not as restrictive.
DESCRIPTION OF THE PREFERRED EMBODIMENT
While the invention is susceptible of various modifications and alternative constructions, certain illustrated embodiments thereof have been described below in detail. It should be understood, however, that there is no intention to limit the invention to the specific form disclosed, but, on the contrary, the invention is to cover all modifications, alternative constructions, alternative uses, and equivalents falling within the spirit and scope of the invention as defined in the claims.
The present invention is a lubricant stick formulation, lubricant sticks made from said formulation, and the method of making said lubricant sticks.
In the preferred embodiment of the present invention, the invented lubricant stick is composed generally of the following formula: from about 25% to about 70% by volume of at least one polymeric carrier (preferably a portion of said polymeric carrier comprising a polylactic acid-based polymer such as polyactide (PLA), more preferably 10% PLA); from about 5% to about 75% by volume of at least one lubricant powder; from about 0% to about 20% by volume of at least one synthetic extreme pressure anti-wear liquid oil; and from about 0% to about 1% by volume of an optical brightener.
Additionally, a portion (preferably 0% to 20%) of the polymeric carrier could be replaced with an impact modifier, preferably derived from the same natural material as the polymeric carrier. The impact modifier is for making the lubricant stick, as formed, less brittle.
Preferably, this polymeric carrier that is mixed with the other compounds of the present invention's formulation begins in one of two forms. The polymeric carrier can be in either a powder or pellet form. When in a pellet form the pellets are usually between 0.1 and 0.15 inch and are irregularly shaped, or in ball, cylinder or hexagon shapes. Suitable polymeric carriers include but are not limited to: polylactic acid-based polymers, other “natural” polymers and biopolymers, polyethylene, polypropylene, methylpentene, polyolefins and/or synthetic waxes.
One or more of the polymeric carriers used in the present invention's formulation could comprise polyactide (also referred to as “PLA,” and as polylactic acid-based polymers/fibers), such as the polymer produced by Cargill Dow LLC and sold under the trade name NATUREWORKS®. PLA is made from lactic acid, this lactic acid typically made from dextrose (made from cornstarch, wheat, sugar beets, dairy products, etc.) by fermentation or chemical synthesis. PLA is a biodegradable thermoplastic that in the environment can degrade within a matter of weeks. By using PLA as some or all of the polymeric carrier used, lubricant sticks of the present invention's formulations are more environmentally friendly.
My prior patent (U.S. Pat. No. 6,649,573) discloses the use of a one and/or two part stick formulation. The present invention includes any use of PLA in a lubricant stick, both one part and two part (or more) stick formulations. Thus, the first portion could include PLA, the second portion could include PLA, both portions could include PLA and/or a stick having a single portion could include PLA. In the preferred embodiment of a lubricant stick claimed here, the lubricant stick is of a single (one-part) formulation.
Additionally, applicant has found that the replacement of a portion of the polymeric carrier with cornstarch (or other complex carbohydrate) results in the remnants (the portion that wears off on the wheel flange (as the lubricant is applied to the wheel flange)) of polymeric carrier, which fall onto the ground breaking down considerably faster than without such an additive. While the amount of polymeric carrier (such as polyethylene) that becomes littered along the railway is minuscule, it never hurts to be more environmentally conscious (whether it is through adding cornstarch or using PLA) and through using embodiments of the present invention that is accomplished.
The impact modifier is preferably derived from the same natural material as the polymeric carrier. The impact modifier for making the lubricant stick, as formed, less brittle.
In the preferred embodiment, the lubricant stick uses about 5% to 75% of at least one lubricant powder by volume, this lubricant powder preferably a combination of about 80% molybdenum disulfide powder, and 20% graphite powder. It is likewise preferred that the lubricant stick further comprise between 1% and 4% by volume of at least one synthetic extreme pressure anti-wear liquid oil and about 1% of at least one optical brightener.
Other combinations of these and other ingredients will be obvious to one skilled in the art and the above formulation is given by way of illustration only. For example, the percentage of polymeric carrier(s) used can vary according to how quickly or slowly a user desires the solid lubricant be deposited against a steel surface. Likewise, the percentage of inorganic powder (such as molybdenum disulfide) can vary depending on how much organic powder (such as graphite) is used, and likewise, the percentage of organic powder used can vary depending on how much inorganic powder is used.
With respect to the liquid oil, such use is optional. Additionally, when used, the amount of liquid oil used varies from 0% to about 20% by volume of the composition. More than one type of liquid oil can be used and the percentage used can be varied depending on the percentage of inorganic or organic powders used, in example, the percentage of liquid oil can be varied depending on the percentage of liquid oil or oils needed for blending of the dry powdered materials. The addition of an optical brightener is also not required, but is preferably used so that by using a black light, the lubricant deposition on wheel flanges or rail track can be verified.
The lubricant powder(s) are used as an anti-wear additive. The lubricant powder(s) comprising 5% to 75% by volume of the formulation of the lubricant stick. In its preferred embodiment, the lubricant stick contains a minimum of about 65% by volume of one or more of inorganic molybdenum disulfide powder, graphite powder, talc powder, mica powder or calcium carbonate powder. The significant percentage of these extreme pressure anti-wear powders provides the lubrication necessary to prevent excessive wear due to rolling and sliding contact between wheel flanges of a locomotive and rail track.
The synthetic liquid oil in the formulation of the present lubricant stick also acts as an extreme pressure anti-wear additive. The preferred synthetic liquid oil is a biodegradable mineral-based oil that assists in the blending of the polymeric carrier and the extreme pressure anti-wear powders. Natural oils, including but not limited to corn oil and soybean oil, could likewise be used. A preferred ratio of about four parts per hundred to about fifteen parts per hundred of the oil can be used. In the preferred embodiment, about 5% by volume of oil in the formulation is the most effective. Less than 4% of oil by volume in the formulation is not sufficient to contribute to the mixing of the anti-wear powders and the polymeric resin of the polymeric carrier and is thus less preferred.
As previously indicated, optical brightener allows the lubricant of the present invention to be seen under black light conditions (one could shine a black light onto the railcar flange to see if the lubricant stick was applying lubricant to the flange). The optical brightener therefore verifies that the solid lubricant is coating the surface to which it is being applied. About 1% by volume of optical brightener is preferred in the formulation to ensure visibility, however 0% to about 1% by volume may be utilized.
There is a multi-step process of producing the lubricating stick. First, all materials (polymeric carrier, lubricant, oil, and/or optical brightener) are blended and extruded into pellet size shapes. It is however, not necessary to pelletize the ingredients first, for instance, they can be mixed together very well with a heavy duty mixer that confines dust, or any other manner of pelletizing the ingredients that keeps dust from flying freely. Second, a desired shape of the solid lubricant stick is made using extrusion, transfer molding, injection molding, etc.
While there is shown and described the present preferred embodiment of the invention, it is to be distinctly understood that this invention is not limited thereto but may be variously embodied to practice within the scope of the following claims. From the foregoing description, it will be apparent that various changes may be made without departing from the spirit and scope of the invention as defined by the following claims.
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A solid lubricant and composition useful for lubricating the flanges of locomotive wheels, railcar wheels, rail tracks and in applications where it is desirable to reduce friction when metal contacts metal. The solid lubricant having from about 25% to about 70% by volume of a biopolymer polymeric carrier, about 5% to 75% percent by volume of organic and inorganic extreme pressure additives, about 0% to 20% by volume synthetic extreme pressure anti-wear liquid oil, and about 0% to 1% by volume optical brightener.
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BACKGROUND
The present invention concerns the provision of security to computing devices and pertains particularly to providing password protection which utilizes a variable master password.
In many computing devices it is desirable to prohibit access by utilizing passwords. For example, in some phone systems available from Siemens Rolm Communications, Inc., having a business address of 2205 Grand Avenue Parkway, Austin Tex. 78728, configuration data is protected through a customer-defined password mechanism. However, a customer may forget the chosen password and thus not be able to change the configuration of the phone or access the functions protected by the password.
Various schemes have been considered to allow a customer to recover from the loss of a password. In one scheme, the customer calls a technical support number. The technical support representative provides the user with a master password which is effective for the phone model. The customer then uses the master password to change the configuration of the phone or access the functions protected by the password. The master password is also used to program a new password which the customer will remember.
One problem with the use of a master password which is effective across a phone model is that once the master password becomes known to users, this renders password protection compromised and thus ineffective.
Alternatively, each individual phone could have its own master password. When the customer calls a technical support number after losing his or her password, the technical support representative asks for the serial number of the telephone. The service representative then consults a list of all serial numbers which includes corresponding master passwords.
One problem with the use of a personalized master password for each individual phone is the extra cost required to program each phone with its own personalized master password. In addition, if any portion of the list of personalized master passwords is lost, then there would be no way to unlock the pertinent phones.
SUMMARY OF THE INVENTION
In accordance with the preferred embodiment of the present invention, access is granted to a portion of a computing system. For example, access is granted to a configuration menu of a telephone system. In order to grant access, a password is received from a user. A variable password is also calculated. The variable password varies with time. For example, the variable password varies with a current date and with a time of day stored and updated by the computing system. The password received from the user is compared with the calculated variable password. When the password received from the user is equal to the calculated variable password, access is granted. In addition, in the preferred embodiment, when the password received from the user is equal to a user-defined password previously entered into the computing system, access is also granted.
The use of a variable password as a master password allows a user to recover from the loss of a password. For example, each telephone system of a particular telephone system model can utilize the same variable password. Then if the user forgets the user-defined password, the user can call a technical support number. The technical support representative obtains from the user the time (e.g., date and time of day) displayed by the telephone system. Using this information and the relevant algorithm, the technical support representative calculates the current valve for the variable master password for the time displayed by the telephone system. The technical support representative then provides the current value for the variable master password for the time (e.g., date and time of day) displayed by the telephone system to the user. The user uses this variable master password to access the configuration menu. Once inside the configuration menu the user can either remove the password or program a new password.
The use of a variable master password allows for protection against the loss by the user of a user-defined password. Because the variable master password uses the same algorithm to be calculated, there is no extra cost required to program each telephone. Also there is no list of personalized master passwords which can be lost. In addition, a user who knows a variable master password cannot use the variable master password on other phones, once the current value for the variable master password changes. This insures the continuing integrity of the password protection.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a telephone system with a display.
FIG. 2 shows logic blocks of the telephone system shown in FIG. 1 .
FIG. 3 and FIG. 4 show various information displayed by the telephone system shown in FIG. 1 when accessing a configuration menu.
FIG. 5 and FIG. 6 show various information displayed by the telephone system shown in FIG. 1 when entering a new password.
FIG. 7 is a flowchart which illustrates operation of the password feature of the telephone system shown in FIG. 1 in accordance with a preferred embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a telephone system 10 . Telephone system 10 includes a handset 16 , a display 11 , and a dialpad 17 . Telephone system 10 also includes a program key 12 , a program key 13 , a program key 14 and a program key 15 which can be used in the course of accessing programming features of telephone system 10 . Additional feature keys 18 also are included within telephone system 10 .
FIG. 2 shows a block diagram of internal logic within telephone system 10 . As shown in FIG. 2, telephone system 10 includes a central processing unit (CPU) 25 , read only memory (ROM) 22 , random access memory (RAM) 27 , non-volatile random access memory (NVRAM) 21 , handset logic block 24 , liquid crystal display (LCD) logic 23 , keypad logic 28 , and integrated services digital network (ISDN) line interface logic 26 .
NVRAM 21 stores configuration data for telephone system 10 . NVRAM 21 is also available for storage of programs; however, this is done in an area of NVRAM 21 separate from the configuration data. LCD display logic 23 is used to drive LCD display 11 . LCD display 11 is used to display telephone information and to echo user input. Keypad logic 28 is used to receive input from dialpad 17 and program keys 12 , 13 , 14 and 15 . ISDN line interface logic 26 provides an interface to the public ISDN network. CPU 25 is a microprocessor which provides processing power for telephone system 10 .
Telephone system 10 provides configuration capability which is protected by a password. The configuration menu is accessible when telephone system 10 is not in use by depressing program key 14 or program key 13 until a “Configure phone?” display appears in LCD display 11 . The “Configure phone?” display is shown in FIG. 3 . Once the “Configure phone?” display appears in LCD display 11 , the configuration feature is selected by depressing program key 12 .
If a user has previously defined a password, selecting the configuration feature by depressing program key 12 when the “Configure phone?” display appears in LCD display 11 results in a message which prompts for a password appearing in LCD display 11 , as shown in FIG. 4 . When this message appears, a user must enter the password from dialpad 17 before accessing the phone configuration menu.
The password is entered by the user depressing keys on dialpad 17 . For each digit or symbol entered, an asterisk (*) is displayed. If a mistake is made, program key 13 can be depressed to backspace. When a user finishes typing the password, the password is entered by pressing program key 12 .
Once in the configuration menu, a password may be added or changed by pressing program key 14 or program key 13 until “Password?” appears on the display, as shown in FIG. 5 . The “password” feature is then selected by pressing program key 12 . Once program key 12 is pressed the user is prompted to type in a new password by the display shown in FIG. 6 . In the preferred embodiment, a password is 1 to 7 digits. ‘*’ and ‘#’ may be included as part of the password. To delete the password, the user presses program key 13 until only blanks show on display 11 . To save the new password, the user presses program key 12 .
In the preferred embodiment of the present invention, telephone system 10 prompts for the new password for verification before leaving the password menu.
If the user forgets the chosen password, the user is not granted access to change the configuration of telephone system 10 or access of the functions protected by the password. In the preferred embodiment of the present invention, this is remedied by the use of a variable master password. The variable master password is dependent, for example on the time (e.g., date and time of day) accessed.
FIG. 7 is a flowchart which illustrates operation of the password feature of telephone system 10 , including use of the variable master password. In a step 41 , telephone system 10 receives the password from the user. When the user finishes typing the password, the user presses program key 12 .
In a step 42 , telephone system 10 compares the entered password with the user-defined password previously stored by the user. If the entered password is the same as the user defined password previously stored by the user, in a step 46 , the user is granted access to the configuration menu.
In step 42 , if the entered password is not the same as the user-defined password previously stored by the user, in a step 43 , the variable master password is calculated based on the time (i.e., current date and/or time of day) stored by telephone system 10 . The algorithm used to calculate a variable master password may be any mathematical algorithm which uses as a variable one or more of the following time information: year, month, day, hour, minute, second.
For example, typically, the algorithm used to calculate variable master password is a mathematical algorithm which uses as a variable the current year, month, day and hour. This means that each variable master password is good for up to one hour. For example, the algorithm shown in Table 1 below may be used to calculate the variable master password:
Table 1
(Year+2666) (month+12) (day of month+31) (hour of day+24)
The least significant seven digits of the result of the algorithm calculated in Table 1 above are used as the variable master password. Alternatively, any other method of calculating the variable master password may be utilized so along as the method of calculating the variable master password uses as a variable one or more of the following time information: year, month, day, hour, minute, second.
In a step 44 , telephone system 10 compares the entered password with the variable master password calculated in step 43 . If the entered password is the same as the variable master password calculated in step 43 , in step 46 , the user is granted access to the configuration menu.
In step 44 , if the entered password is not the same as the variable master password calculated in step 43 , in a step 45 , the user is denied access to the configuration menu and prompted to enter another password.
In alternative embodiments of the present invention, one or more passwords used for factory diagnostics may be added. In this case the flowchart shown in FIG. 7 can be modified to check for the password(s) used for factory diagnostics. For example, for the flowchart shown in FIG. 7, the password used for factory diagnostics could be checked first.
The use of a variable master password allows the user to recover from the loss of a password. For example, each telephone system of a particular telephone system model can utilize a same variable password. Then when the user forgets the user-defined password, the user can call a technical support number. The technical support representative obtains from the user the time (i.e., date and time of day) displayed by the telephone system. Using this information and the relevant algorithm, the technical support representative calculates the current value for the variable master password for the time displayed by the telephone system. The technical support representative then provides the current value for the variable master password for the time (i.e., date and time of day) displayed by the telephone system to the user. The user uses this variable master password to access the configuration menu. Once inside the configuration menu the user can either remove the password or program a new password.
The use of a variable master password allows for protection against the loss by the user of a user-defined password. Because the variable master password uses the same algorithm to be calculated, there is no extra cost required to program each telephone. Also there is no list of personalized master passwords which can be lost.
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Access is granted to a portion of a computing system, such as to a configuration menu of a telephone system. In order to grant access, a password is received from a user. A variable password is also calculated. The variable password varies with time. For example, the variable password varies with a current date and with a time of day stored by the computing system. The password received from the user is compared with the calculated variable password. When the password received from the user is equal to the calculated variable password, access is granted.
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TECHNICAL FIELD
[0001] The present invention relates to a cardanic suspension device for a camera balance device according to the characterizing part of claim 1 .
[0002] Camera balance devices of this kind are used to balance video and film cameras which are guided manually by a camera operator and are connected by means of a suspension device, for example, to a spring arm in a waistcoat-type carrying device (so-called body support) which is in turn attached to the body of the camera operator.
[0003] The suspension device is intended to prevent tilting and inclined movements, oscillations and stepping movements from the body of the camera operator being transmitted to the camera because it is necessary to guarantee a constant camera alignment at all times and avoid any tilting, inclination or oscillation of the camera. Alternatively, the camera attached to the balance device may also be secured by means of the suspension device to a free-standing support, dolly, crane etc, whereby the suspension device is then able to prevent any unevenness of the ground exerting an influence on the position of the camera.
[0004] For this, the suspension device is designed so that the construction comprising camera and balance system is able to execute a pendulum motion relative to the support. In addition, this construction is connected to counterweights. With a suitable choice and positioning of these counterweights, the camera is balanced in such a way that tilting and inclination movements, oscillations and stepping movements are not transmitted from the body support, free-standing support, dolly or crane, etc. to the camera.
PRIOR ART
[0005] In a known camera balance device, the camera is attached to one end of a pendulum arm to the other end of which the counterweights are fixed. Batteries are used, for example, as counterweights, which simultaneously function as energy stores.
[0006] The pendulum arm is connected to a cardanic suspension device which may in turn be attached, for example, to a spring arm in a body support, to a support, dolly or crane.
[0007] In the cardanic suspension of the camera construction, three axes of motion are realized relative to the support: the suspension device comprises two intersecting joint axes (cardanic axes) one of said axes extending vertically (in a perpendicular manner) during operation and the other extending horizontally, in addition to an axis of rotation, extending through the vertical joint axis and lying perpendicular to the horizontal joint axis. A joint output fixing element can be rotated about the vertical joint axis and is used to fix the cardanic suspension device to the pendulum arm of the camera balance device, and a joint input fixing element, which may rotated about the axis of rotation, is used to fix the cardanic suspension device to a support, in particular to the aforementioned body support or also to a free-standing support.
[0008] U.S. Pat. No. 5,797,054 discloses a cardanic suspension for a camera balance device according to the characterizing part of claim 1 . However, here the clamp device for fixing the suspension device to the pendulum arm in the camera balance device is located in the area of the cardanic suspension so that the clamping process can result in the decentralization of the cardanic joint in relation to the three axes.
DESCRIPTION OF THE INVENTION
[0009] The object of the present invention is to provide an improved cardanic suspension for a camera balance device with which the balance setting is maintained over a wide range of camera movements and the decentralization of the cardanic joint is avoided.
[0010] This object is achieved by a cardanic suspension device according to claim 1 . According to this, the output fixing element is fixed to the camera balance device by means of a clamp device which is arranged in such a way that the clamp device and the centering device are located at distance from each other, preferably at opposite ends, on the joint output fixing element
[0011] The invention is based on the knowledge that the smallest deviations in the centering of the cardanic suspension device relative to the pendulum arm exert a significant influence on the balance set by means of the counterweights. Deviations in the centering of this kind can, for example, be caused by tolerance deviations in the external diameter of the pendulum arm and result in substantial errors in the camera guidance, in particular if this is performed at high speeds.
[0012] Therefore, it is particularly important that in the area of the cardanic joint where the two joint axes and the axis of rotation meet there is no slip between the suspension device and the pendulum arm.
[0013] The centering according to the invention guarantees that that a balance set by means of the counterweights is also retained, for example, if the camera construction rotates about 360° relative to the support or the camera operator with the suspension device moves through 360°. If the centering is not performed precisely, even with rotations of less than 180°, balance deviations occur in certain places, which in particular with rapid movements, results in faulty camera guidance.
[0014] The fixing of the output fixing element to the camera balance device is preferably achieved by means of a clamp device, which is arranged in such a way that the clamp device and the centering device are located at a distance from each other and preferably at opposite ends of the joint output fixing element. The clamp device for fixing the suspension device to the pendulum arm in the camera balance device is then located as far away as possible from the cardanic suspension so that the clamping process cannot not result in the decentralization of the cardanic joint relative to the three axes.
[0015] Advantageous further developments of the cardanic suspension device according to the invention may be found in the dependent claims.
[0016] In one advantageous further development of the cardanic suspension device according to the invention, the joint input and/or the joint output fixing element is formed as a handle. The joint input handles may be used to attach the suspension device to a spring arm in the camera operator's waistcoat, to a support or similar. In addition, for manipulation, the joint output handle is also used for placing the suspension device on the pendulum arm in the camera balance device.
[0017] The centering device can be adjustable, preferably steplessly adjustable.
[0018] In an advantageous further development, the joint output fixing element is formed as a straight tube. In this case, it is able to slide over the correspondingly formed pendulum arm in the camera balance device. Preferably, the suspension device is arranged movably on the camera balance device or on the pendulum arm in order to change its position relative to the camera and counterweights.
[0019] The tube can, for example, have a circular section. Also conceivable is a rectangular or square embodiment.
[0020] In one advantageous embodiment, the centering device is formed by an adjusting ring provided with a clamping cone, which in turn interacts with a clamping ring. If the joint output fixing element is formed, as described above, as a tube with a circular cross section, the adjusting ring can be screwed into one end of the tube and interact with a clamping ring arranged on the camera balance device.
[0021] The clamping ring is preferably made of plastic. It can, however, also be made of metal, ceramic, a composite material or a combination of these materials. Preferably, there is at least one slot in the ring in order to increase deformability and adaptability to the pendulum arm in the camera balance device which extends therein.
[0022] The threaded ring is in turn preferably made of metal, but can, however, also be made of plastic, ceramic, a composite material or a combination of these materials.
[0023] The suspension device according to the invention can also have a second centering device between the joint input and the joint output fixing elements, with which the vertical joint axis and the axis of rotation are able to move relative to each other. In this case, the centering takes place in a double manner: one centering device may be used to establish the relative position between the joint output fixing element and the camera balance device in the area of the two joint axes without slip. The second centering device may be used to move the vertical joint axis and the axis of rotation relative to each other, preferably along the horizontal joint axis.
[0024] In an advantageous embodiment of the invention, the vertical joint axis may be moved along the axial extension of the horizontal joint axis by means of the second centering device. Here, the vertical joint axis may be moved by means of at least one adjusting screw. A particularly preferred embodiment has two adjusting screws whose longitudinal axes extend along the horizontal joint axis. However, it also conceivable to provide only one adjusting screw and one spring-loaded thrust bearing opposite to this so that the adjustment is performed by turning this adjusting screw.
SHORT DESCRIPTION OF THE DRAWINGS
[0025] The following describes the invention in more detail with reference to an example of an embodiment shown in the drawings.
[0026] These show:
[0027] FIG. 1 an overall view of a camera balance system and a cardanic suspension device according to the invention,
[0028] FIG. 2 a detailed view of the cardanic suspension device according to the invention
[0029] FIG. 3 a side view of the cardanic suspension device according to the invention, partially in section, and
[0030] FIG. 4 a top view of the cardanic suspension device according to the invention, partially in section.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0031] FIG. 1 shows a camera balance device 1 together with a cardanic suspension device according to the invention 3 .
[0032] The camera balance device comprises a pendulum tube 5 . At the upper end of the pendulum tube 5 there is a camera fixing device 7 , which substantially comprises a base 9 and a holding plate 11 to which a camera may be attached, whereby the holding plate 11 may be moved relative to the base 9 by means of adjusting screws 13 (only one of which is shown here) and to be precise into the plane of projection shown in FIG. 1 or out of this plane. Other adjusting screws (not shown) are provided in order to move the holding plate 11 in FIG. 1 to the right and left relative to the base 9 . At the lower end of the pendulum tube 5 there is a holding device 15 for counterweights. Provided in this embodiment are a monitor holder 17 and two backing plates 19 , 19 ″ to hold counterweights, which take the form of batteries, for example. The backing plate 19 is attached movably and fixably to sliding tubes 21 (of which only one is visible) and may also be swiveled relative to the sliding tube 21 ; the backing plate 19 is locked in the desired angular position by means of a clamping lever 23 .
[0033] The construction comprising the pendulum tube 5 , the camera holding device 7 and the holding device 15 for counterweights is now cardanically suspended in a suspension device 3 according to the invention. This suspension device 3 is shown in more detail in FIGS. 2 to 4 and comprises a first handle 25 as a joint input fixing element and a second handle 27 as a joint output fixing element. The first handle 25 is used to attach the suspension device to a support, in particular to a body support worn by a camera operator. For this, the joint input handle has a drill hole 26 by means of which it may be placed on a pivot on an upright stand or a spring arm in a waistcoat. The second handle 27 is used to attach the suspension device 3 to the camera balance device 1 . For this, the second handle 27 has a tubular shape and is arranged around the pendulum tube 5 in the camera balance device 1 so that it may be moved relative to the pendulum tube 5 . The second handle 27 is locked relative to the pendulum tube 5 by means of a clamp device 29 .
[0034] By means of the two handles 25 , 27 , a camera operator can guide with both hands the construction fixed by means of the first handle 25 for example to a spring arm, a body support, an upright stand, dolly or crane.
[0035] Three axes of motion are realized in the joint connection between the first handle 25 and the second handle 27 : the first handle 25 is connected to a fork element 31 in such a way that it may be rotated relative to this fork element 31 about an axis of rotation D corresponding to the longitudinal axis of a straight section of the first handle 25 extending horizontally in FIG. 1. The fork element 31 is in turn connected swivelably about a horizontal joint axis G 1 (first cardanic axis) to a joint outer ring 33 . This joint outer ring 33 is in turn coupled rotatably about a vertical joint axis G 2 (second cardanic axis) to a joint inner ring 35 , which in turn is in a fixed connection with the second handle 27 , which is attached by the clamp device 29 to the pendulum tube 5 in the camera balance device 1 . Hence, the first handle 25 , which may be connected to the support, may be rotated in relation to the second handle 27 connected to the pendulum tube 5 about the axis of rotation D, swiveled about the horizontal joint axis G 1 and mounted rotatably about the vertical joint axis G 2 .
[0036] The joint suspension device 3 is intended to prevent movements of the support, for example the body support, being transmitted to the camera attached to the holding plate 11 . For this, the construction comprising the pendulum tube 5 , camera holding device 7 and counterweights must be positioned on the holding device 15 with balance compensation. To achieve this balance compensation in particular also for different camera types with different weights and different locations of the center of gravity, the camera balance device 1 has a plurality of setting options. In particular, the system balance is achieved by the provision of counterweights of varying heaviness on the holding device 15 . As already mentioned above, the backing plate 19 for counterweights is also mounted in a swivelable and movable way. The same may apply to the monitor holding device 17 . The embodiment shown has as the holding device 15 for counterweights the monitor holder 17 and two backing plates 19 , 19 ″; it is also obviously conceivable to provide other means of attachment for counterweights at different points of the pendulum tube 5 .
[0037] As also mentioned above, in addition the adjusting screws 13 may be used to move the center of gravity of the camera (not shown) on the holding plate 11 relative to the base 9 connected to the pendulum tube 5 . An even more flexible system may be obtained if the pendulum tube 5 is telescopic.
[0038] The slightest deviations in the centering of cardanic suspension device 3 , or to be more precise of the joint inner ring 35 , relative to the pendulum tube 5 exert a significant influence on the balance set by means of the counterweights. Deviations in the centering of this kind can, for example, be caused by tolerance deviations in the external diameter of the pendulum tube 5 and result in substantial errors in the camera guidance, in particular when this is performed at high speeds.
[0039] For this reason, the suspension device according to the invention has on one side a centering device 37 with which the relative position between the second handle 27 and the pendulum tube 5 may be established without slip. FIG. 3 elucidates this centering device 37 , which is provided in the area of the two intersecting joint axes G 1 and G 2 . The centering device 37 and the clamp device 29 , which is used to fix the second handle 27 to the pendulum tube 5 , are therefore located at opposite ends of the second handle 27 . The distance between this clamp device 29 and the centering device 37 prevents the clamping of the clamp device 29 from having a detrimental impact on the centering device 37 , i.e. from causing the decentralization of the suspension device 3 relative to the two joint axes G 1 and G 2 and the axis of rotation D.
[0040] The centering device 37 according to the invention has an adjusting ring 39 provided with a thread which is screwed into the joint inner ring 35 . In this embodiment, the centering device 37 is steplessly adjustable due to the thread. This adjusting ring 39 has in its interior a cone which presses on a counter-cone in a slotted clamping ring 41 made of plastic, which is provided on the pendulum tube 5 . The centering of the two elements is therefore achieved by the interaction of the cone of the adjusting ring 39 with the cone of the clamping ring 41 . The adjusting ring 39 is preferably made of metal.
[0041] If the second handle 27 is pushed onto the pendulum tube 5 and said tube is in the desired position, the handles 27 are fixed at a long distance from the joint axes G 1 , G 2 by the clamp device 29 , and the centering is performed by the adjusting ring 39 and the clamping ring 41 . This will prevent any slip, and in this position, reliable and good centering of suspension device 3 relative to the pendulum tube 5 is achieved. In addition, the suspension device 3 will also be fixed to the pendulum tube 5 at this point. However, the adjusting ring 39 and the clamping ring 41 are primarily used for the centering and only subordinately for fixing.
[0042] In addition, in the arrangement according to the invention, both the clamp device 29 and the centering device 27 are easy to access.
[0043] The suspension device according to the invention 3 also has another centering device 43 , which will now be described with reference to FIG. 4. This other centering device 43 is used to move the vertical joint axis G2 relative to axis of rotation D and in this way to center the pendulum tube 5 in the camera balance device 1 relative to the fork element 31 in the suspension device 3 according to the invention. In the embodiment shown, this centering device 43 is achieved by two adjusting screws 47 , which are screwed into the fork element 31 by means of very fine threads and are also mounted swivelably relative to the joint outer ring 33 . In this way, these adjusting screws provide the connection between the fork element 31 and the joint outer ring 33 . The adjusting screws 47 have entry holes 45 for a tool. Turning the adjusting screws 47 achieves the centering of the fork element 31 relative to the pendulum tube 5 by moving the threaded outer ring 33 and hence the vertical joint axis G 2 along the horizontal joint axis G 1 relative to the fork element 31 and hence relative to the axis of rotation D. Here, the fine threads of the adjusting screws 47 permit adjustment in the range of hundredths of millimeters. In this way, the joint outer ring 33 and hence the pendulum tube 5 can be arranged exactly centrally relative to the fork element 31 .
[0044] One of the two adjusting screws 47 can also be replaced by a spring-loaded thrust bearing.
[0045] The centering device 43 supplements the centering device 37 to achieve a further improvement to the alignment of the suspension device 3 according to the invention relative to the camera balance device 1 .
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Disclosed is a cardiac suspension device ( 3 ) for a camera balance device ( 1 ), comprising two intersecting joint axes (G 1 , G 2 ); one of said axes extending vertically (G 2 ) (in a perpendicular manner) during operation and the other (G 1 ) extending horizontally, in addition to an axis rotation (D) extending through the vertical joint axis (G 2 ) and lying perpendicular to the horizontal joint axis (G 1 ). A joint output fixing element ( 27 ) can be rotated around verticalmjoint axis (G 2 ) and is used to fix the cardanic suspension device ( 3 ) on the camera balance device ( 1 ). A joint input fixing element ( 25 ) can rotate around the axis of rotation (D) and is used to fix the cardanic suspension ( 3 ) to a support. A centerin g device ( 43 ) is provided in the region of the vertical joint axis (G 2 ) and the horizontal joint axis (G 1 ), enabling the relative position between the joint output fixing element ( 27 ) and the camera balance device ( 1 ) to be established without slip in said region.
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This application is a division of application Ser. No. 09/334,105, filed Jun. 16, 1999, now U.S. Pat. No. 6,569,651.
This invention was made with Government support under ARO Cooperative Grant DAAH04-94-2-003. The Government may have certain rights in the invention.
FIELD OF THE INVENTION
The invention relates to methods for polymerizing a monomer enzymatically in the presence of a template to form a polymer-template complex.
BACKGROUND OF THE INVENTION
Recently, there has been an increased interest in the tailored development of certain classes of polymers, such as electrically conductive and optically active polymers (e.g. polythiophene, polypyrrole, and polyaniline) for application to wider ranges of use. Examples of such uses include light-weight energy storage devices, electrolytic capacitors, anti-static and anti-corrosive coatings for smart windows, and biological sensors. However, the potential applications of these polymers have been limited by some fundamental properties of the monomers employed to form these polymers and by limitations of known polymerization techniques.
Electrically conductive and optically active polymers are relatively insoluble in water. Therefore, these polymers are typically formed in an organic solvent. Attempts to increase the water solubility of these polymers have included derivatization of the monomer before polymerization or the resulting polymer formed. However, derivatization of monomers typically slows polymerization, while derivatization of polymers generally causes some degradation.
Moreover, the physical properties of polymeric materials generally can be manipulated only by mechanical means such as extrusion, or by polarization of relatively short polymers or oligomers in an electric field. Further, the existing synthetic methods of forming polymers generally do not provide means for manipulating their shape during polymerization.
Therefore, a need exists to overcome or minimize the above-referenced problems associated with polymer synthesis.
SUMMARY OF THE INVENTION
The invention relates to novel methods for enzymatic polymerization which include (1) obtaining a reaction mixture including a monomer, a template, and an enzyme, and (2) polymerizing the monomer aligning along the template to form a polymer-template complex. Not only does such a complex possess high molecular weight, high water solubility, and exceptional electrical and optical properties, its preparation is also simple, environmentally friendly, and inexpensive. Its excellent properties enable the complex to be used in many applications. For example, polyaniline-lignin sulfonate complexes can be used as an emulsifier in asphalt, or a dispersant for cement mixes, fertilizers, linoleum paste, dust suppressants, dyes and pigments. As another example, new polyaniline-micelle complexes, which form a spherical polymer shell, can be used for paints, coatings, and also for entrapping and transporting materials, e.g., pharmaceuticals, that are generally insoluble in aqueous media.
One aspect of this invention relates to novel methods for enzymatic polymerization. The methods include obtaining a reaction mixture including a monomer (e.g., aniline or phenol), a micelle (e.g., a micelle template with positively charged or negatively charged groups on the surface), and an enzyme (e.g., a peroxidase such as horseradish peroxidase); and incubating the reaction mixture for a time and under conditions sufficient for the monomer to align around the micelle surface and polymerize to form a polymer-micelle complex. The method further includes combining an electron acceptor, such as hydrogen peroxide, with the reaction mixture to initiate the polymerization. The reaction mixture in the novel method has a pH of between about 4 and about 10 (e.g., between about 6 and about 8).
The micelles used in the novel methods include multiple units. Each unit has a hydrophobic part and a hydrophilic part. The hydrophilic part includes an aromatic ring (e.g., benzene) bonded to an acidic substituent (e.g., sulfonate) with a pK a of the acidic substituent ranging from 0.5 to 3.5 (e.g., 0.5 to 2.5). Some examples of such a micelle unit are dodecyl benzene sulfonic acid, octadecyl benzene sulfonic acid, and hexadecyl naphthyl sulfonic acid.
Another aspect of this invention relates to novel polymer-micelle complexes including a polymer bound to a micelle. The novel complexes have a molecular weight ranging from 70 kD to 10,000 kD (e.g., 100 kD to 7,000 kD) and can be electrically conducting and/or water soluble. The novel complexes can also be optically active. An example of the novel complex is polymer-dodecyl benzene sulfonic acid (e.g., polyaniline-dodecyl benzene sulfonic acid or polyphenol-dodecyl benzene sulfonic acid).
A further aspect of this invention relates to a novel method for enzymatic polymerization. The method includes obtaining a reaction mixture including a monomer (e.g., aniline or phenol), a template, and an enzyme (e.g., a peroxidase such as horseradish peroxidase); and incubating the reaction mixture for a time and under conditions sufficient for the monomer to align along the template and polymerize to form a polymer-template complex. The method further includes combining hydrogen peroxide with the reaction mixture to initiate the polymerization. The reaction mixture in the novel method has a pH that is greater than 4 (e.g., between about 4 and about 10 or between about 6 and about 8).
The template can be lignin sulfonate or a borate-containing polyelectrolyte; both of which contain charged groups (i.e., sulfonate or borate) that are responsible, at least in part, for aligning the charged monomers. Borate-containing polyelectrolytes can be a polymer (e.g., polyvinyl) containing positively or negatively charged groups. Examples of such charged groups include trifluoroborate [—BF 3 ] − , trimethylborate [—B(CH 3 ) 3 ] − , and hydrobis(pyridine)boron [—BH(C 5 H 5 N) 2 ] + .
A still further aspect of this invention relates to novel polymer-template complexes including a polymer bound to a template. The novel complexes have a molecular weight ranging from 70 kD to 10,000 kD (e.g., 100 kD to 7,000 kD). The complexes can be electrically conducting and/or water soluble and can act as a charge-transfer complex or an optically active complex. Examples of the novel complexes include polymer-lignin sulfonate (e.g., polyaniline-lignin sulfonate or polyphenol-lignin sulfonate) and polymerborate-containing polyelec-trolyte (e.g., polyaniline-tetrafluoroborate-containing pqlyelectrolyte or polyphenol-tetramethylborate-containing polyelectrolyte).
A template binds to and aligns the monomers so as to maximize conjugation and minimize branching of the polymers formed according to the new methods. The template can be a polyelectrolyte. The template can also be a micelle, an oligomer, or a polymer. Examples of suitable templates include an azo polymer, a substituted polystyrene, a substituted vinyl polymer (e.g., polyvinyl phosphonate, polyvinyl phosphate, or polyvinyl benzoic acid), a sulfonated polymer (e.g., lignin sulfonate, sulfonated polystyrene, or polystyrene sulfonic acid), a polynucleotide (e.g., deoxyribonucleotide or ribonucleotide), a polypeptide, a protein, a biological receptor, a zeolite, a caged compound, an azopolymer, an vinyl polymers (e.g., polyvinyl benzoic acid, polyvinyl phosphate, or polyvinyl borate), polyphenol red, azo compounds, a dendrimer, a protein, or sulfonated micelles (e.g., micelle containing dodecyl benzene sulfonic acid). The template can be positively charged, such as a polycation (e.g., poly(diallyl dimethyl ammonium chloride)) or negatively charged, such as a polyanion (e.g., sulfonated polystyrene). It is important that the charged groups of a template are indeed in their charged form under the required reaction conditions. For example, in the case of a polyanionic template (e.g., lignin sulfonate), the pK a value of the anionic functionalities (e.g., sulfonate) should be sufficiently low (e.g., from about 0.5 to about 3.5) to ensure that they are negatively charged under the reaction conditions (e.g., pH 4.0 to 10.0) so as to bind to and align the positively charged aniline monomers.
A conducting polymer refers to a polymer which exhibits conductivity ranging from about 10 −10 to 10 6 S/cm.
The new template-assisted enzymatic polymerization reactions address problems associated with existing methods of preparing electrically conductive polymers such as the need for harsh chemicals, high costs, difficulty in producing polymeric products with high water solubility and electrical conductivity, and the inability to control shapes and sizes of such products. The polymer-template complexes prepared by this novel polymerization, in addition to being electrically conductive and completely soluble in aqueous media, are also of high molecular weights (e.g., >70 kD).
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety. In case of conflict in terminology, the present specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.
Other features and advantages of the invention will be apparent from the following detailed description, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a scheme showing the general mechanism of enzymatic polymerization of aniline in the absence of a template.
FIG. 2 is a schematic representation of the novel template-assisted enzymatic polymerization. A monomer of interest is first added to an aqueous solution containing a polyelectrolyte template. Under the proper conditions, the monomer associates with the template. Upon adding a suitable enzyme (e.g., horseradish peroxidase) and an oxidant (e.g., hydrogen peroxide), the polymerization proceeds and results in a water-soluble polymer-template complex.
FIG. 3 is a generic chemical formula of a portion of lignin sulfonate.
FIG. 4 is a graph of the visible absorption spectra of a polyaniline template complex (0.05 M aniline to 0.1 M sulfonated polystyrene (SPS)) formed at various pH values.
FIG. 5 is a graph of absorbance versus SPS/aniline ratio that can be used to find the optimum dopant-to-monomer ratio.
FIG. 6 a is a graph showing the visible absorption and redox behavior of polyaniline/SPS prepared at pH 4.0 with increasing pH values.
FIG. 6 b is a graph showing the visible absorbance and redox behavior of polyaniline/SPS prepared at pH 4.0 with decreasing pH values.
FIG. 7 a is a graph showing the visible absorbance and redox behavior of a 50 bilayer film of poly(diallyl dimethyl ammonium chloride) (PDAC) alternating with SPS/polyaniline (prepared at pH 4.0) with increasing pH values.
FIG. 7 b is a graph showing the visible absorbance and redox behavior of a 50 bilayer film of SPS/polyaniline (prepared at pH 4.0) with decreasing pH values.
FIG. 8 a is a graph showing the visible absorbance of polyphenol without SPS versus phenol monomer. Polyphenol precipitated out of solution as a result of polymerization.
FIG. 8 b is a graph showing the visible absorbance of a polyphenol/SPS template versus phenol monomer, where polyphenol did not precipitate out of solution.
FIG. 9 is a graph showing overlapping visible spectra of (1) lignin sulfonate (Lignotech, “LGS”); (2) polyaniline-LGS, horseradish peroxidase (“HRP”), and hydrogen peroxide; and (3) LGS and HRP.
FIG. 10 is a graph showing overlapping visible spectra of (1) polyaniline-dodecyl benzene sulfonic acid (“DBSA”) micelle at pH 4; (2) polyaniline-DBSA micelle prepared at pH 4 and adjusted to pH 10; and (3) aniline monomer and DBSA micelle.
FIG. 11 is a graph showing overlapping visible spectra of (1) polyphenol-DBSA micelle; and (2) phenol monomer and DBSA micelle.
DETAILED DESCRIPTION
The invention is based on the discovery that a template, e.g., polymer or micelle, can effectively associate with a monomer and assist in enzymatic polymerization of such a monomer to produce a high molecular weight polymer complex. The novel enzymatic polymerization method produces polymers that display exceptional electrical and optical stability, water solubility, and processibility, while simultaneously providing a simple (one-step), environmentally friendly, and commercially attractive synthetic approach.
The new methods involve oxidizing a monomer by an enzyme such as peroxidase (e.g., agarose peroxidase, manganese peroxidase, lignin peroxidase, lactoperoxidase, or soybean peroxidase) or laccase. When aniline or phenol is the monomer, oxidation produces a free radical regioselectively at the ortho or para positions of the benzene ring. The oxidized monomers then undergo a coupling reaction to form a polymer with each other. Peroxidase and laccase enzymes typically require electron acceptors such as hydrogen peroxide, oxygen, alkyl hydroperoxide, or percarboxylic acid. The free radical-forming enzymatic reaction (with phenol as the monomer) is illustrated in Scheme I below:
Although enzymatic polymerization in the absence of a template is environmentally friendly, and can offer a high degree of control over the kinetics of the reaction, it is not free of shortcomings. Apart from the fact that only low molecular weight products are obtained, such products are usually a mixture of both ortho- and para-substituted polymers. Further, these ortho- and para-substituted polymers are often branched, thus resulting in reduced electrical and optical properties. FIG. 1 is an illustration of how enzymatic polymerization (with aniline as a monomer) in the absence of a template can result in a complex with undesirable electrical properties such as reduced conductivity.
On the other hand, template-assisted enzymatic polymerization according to the invention minimizes branching of the product and promotes a para-directed, head-to-tail polymerization. A typical template-assisted polymerization reaction (with aniline as the monomer) is illustrated in Scheme II below.
As shown in Scheme II, the template and the polymeric product form a stable complex. The template serves at least three critical functions. First, it serves as a charged scaffold upon which the monomers preferentially align themselves to form a complex, thereby promoting extended conjugation of the resulting polymer chains (limiting parasitic branching). In the case of polyaniline, the mechanism of polymerization is primarily para-directed and results in the electrically active form as shown in Scheme II above. This preferential alignment provides improved electrical and optical properties of the final polymer complex. Second, the template can serve as a large molecular dopant species that is complexed and essentially locked to the polymeric products, e.g., polyaniline or polyphenol. The use of these polymers in electronic and optical applications has been limited because of poor dopant stability. The small ionic dopants or chromophores that are used in existing methods diffuse away from the polymers with time and/or conditions. This locking of a large polyelectrolyte dopant to the polymer ensures that the electrical nature of the polymer's conjugated backbone structure is maintained and that the desired electrical and optical properties are stabilized. Third, the polyelectrolyte template provides water solubility of the final polymer-template complex for environmentally friendly, facile, and inexpensive processing.
The entire process of the novel enzymatic polymerization is illustrated by the drawing as shown in FIG. 2 .
The solvent used in the novel polymerization method is typically water, but can include other organic solvents such as dimethyl formamide, methanol, ethanol, and dioxane. The pH of the solvent ranges from about 4.0 to about 10.0. Preferably, the pH is between about 4.0 and about 5.0 for aniline monomer and between about 6.0 and about 7.0 for phenol monomer. Examples of suitable buffers include Tris-HCl buffer, sodium phosphate, and HEPES.
The concentration of the enzyme in the novel polymerization reaction mixture should be adjusted to a level such that a significant increase in the reaction rate can be achieved. Typically, this concentration ranges from about one unit/ml to about five units/ml, where one unit will form 1.0 mg purpurogallin from pyrogallol in 20 seconds at pH 6.0 at 20° C. Examples of suitable enzymes include peroxidases (e.g., horseradish peroxidase, agarose peroxidase, maganese peroxidase, lignin peroxidase, lactoperoxidase, or soybean peroxidase) and laccase.
Examples of suitable monomers include unsubstituted and substituted aniline (e.g., 2-methylaniline, 2-methoxy-5 methylaniline or 2-ethyl-5-methoxyaniline) as well as unsubstituted and substituted phenol (e.g., 2-ethylphenol, 3-methoxyphenol, or 2-ethoxy-5-isopropylphenol). The monomer can be a cation or an anion. Further, the monomer can be, for example, a dye, such as an azo compound, or a ligand. An oligomer can be employed rather than a monomer. Further, a mixture of different monomers, or even a mixture of oligomers and monomers, can also be used to form polymers using the new methods. Generally, the concentration of a monomer used in the new methods ranges from about 10 mM to about 100 mM.
The concentration of a template added should be sufficient to enable monomers to align along the template throughout the polymerization reaction. Typically, the ratio of the template concentration to the monomer concentration ranges from about 1:10 to about 10:1.
The polymerization reaction is a redox reaction and typically is initiated by adding a suitable oxidant, such as a hydrogen peroxide or a alkyl hydroperoxide solution. In one embodiment, the hydrogen peroxide has a concentration range from about 1 mM to about 5 mM in the reaction mixture. The concentration of hydrogen peroxide solution added to the reaction mixture can be about 30%. The reaction mixture containing monomers, template, and enzyme is stirred while slowly adding the hydrogen peroxide solution to initiate the polymerization reaction. Typically, the reaction mixture is maintained at a temperature ranges from about 10° C. to about 25° C. during polymerization. The resulting polymer can be, for example, a linear polymer, such as an extended linear polymer intertwined with the polyelectrolyte template. Alternatively, the polymer can be dendritic, or branched. It should be noted that the electrical properties of a polymer diminish as it adopts a branched conformation.
The new polymers are electrically conducting because of the electrostatic interaction between the charged groups of the template and the monomer, e.g., aniline. When aniline is used as the monomer, at a low local environmental pH, e.g., pH 4.0, most of the aniline monomers are positively charged (pK a =4.6). To ensure the aniline monomers will bind to the template, the template must also be in its charged form. Templates containing benzene sulfonate groups are particularly suitable because the pK a of such groups are about 0.7 and thus, these groups are negatively charged under the reaction conditions. The benzene rings of the charged groups and the monomers can also interact with each other to further stabilize the complex.
In other embodiments, the polymer can be polyaniline complexed with a polyelectrolyte template, wherein the polyaniline is an extended linear polymer intertwined with the polyelectrolyte template. In a specific embodiment, the polyaniline is a component of a water soluble, electrically conducting complex. The temperature of the reaction mixture can be maintained at a temperature of about 20° C. during polymerization.
Optionally, the method of the invention includes forming a layer of the polymer on a surface. In this embodiment, the pH of the polymer solution is reduced to a suitable pH, such as a pH between about 2.0 and about 8.0, by adding a suitable acid, such as hydrochloric acid or acetic acid. A suitable surface, such as a glass slide treated with an alkali, such as Chemsolv® alkali, is immersed in a polymer solution for a sufficient period of time to cause the polymer to assemble onto the surface via electrostatic interaction. In one embodiment, a glass slide is immersed in a polymer solution for about ten minutes and then removed. The surface can then be washed with water at a pH of about 2.5 to remove unbound polymer from the surface.
Distinct layers of polymers can be applied to a surface by this method. For example, an initial layer can be formed by exposing a suitable surface to a polyanion formed by the methods of the invention, and then subsequently exposing the same surface, having the polyanion deposited upon it, into a solution of a polycation. In one specific embodiment, a glass slide treated with Chemsolv® alkali is exposed to a one mg/ml solution of poly(diallyl dimethyl ammonium chloride) at a pH of 2.5 as a polycation, and then exposed to a one mg/ml solution of sulfonated polystyrene/polyaniline formed by the method of the invention, as a polyanion. A bilayer of polymers is thereby formed. Additional layers of these or other polymers can subsequently be applied. By using this method, a film of polymer layers can be tailor-made to have certain functionalities and thickness. These polymer films can be used as protective coatings, antistatic coatings, or optical filters.
In another embodiment, where the template is an oligomer, polymerization of the template can be initiated simultaneously with, or subsequent to alignment and polymerization of the bound monomer or oligomer. In still another embodiment, the template can be removed from the resulting polymer, such as by decomposition or dissolution, to leave behind a polymer shell.
In one specific embodiment of the methods of the invention, the template-assisted enzymatic polymerization of aniline is carried out in an aqueous solution using 0.1 M sodium phosphate or tris-HCl buffer and a pH ranging from about 4.0 to about 10.0. Aniline monomers typically can be added in a range of between about 10 mM and about 100 mM, and an appropriate amount of a template, in this case sulfonated polystyrene (SPS; molecular weight of 70,000), is added in ratios ranging from about 1:10 to about 10:1 SPS/aniline. The enzyme horseradish peroxidase is then added to the reaction mixture in a range of about one unit/ml to about five units/ml. To initiate the reaction, an oxidizer such as hydrogen peroxide, is slowly added in 10 μl increments over a reaction time of 3 hours, with constant stirring to a final concentration ranging from about 10 mM to about 100 mM.
In another specific embodiment of the new methods, the template-assisted enzymatic polymerization of phenol is carried out in an aqueous solution using 0.1 M sodium phosphate or tris-HCl buffer at a pH ranging from about 4.0 to 10.0. Phenol monomers are added in a range from about 10 mM to about 100 mM, and an appropriate amount of the template SPS is added in ratios ranging from about 1:10 to about 10:1 SPS/phenol. Horseradish peroxidase is then added to the reaction mixture in a range of approximately one to five units/ml. To initiate the reaction, an oxidizer, such as hydrogen peroxide, is slowly added in 10 μl increments over a reaction time of about 3 hours, with constant stirring to a final concentration ranging from about 10 mM to about 100 mM.
In another embodiment, lignin sulfonate is used as a template in the novel polymerization reaction, thus resulting in an electrically conducting, water-soluble polymer which is doped by lignin sulfonate. See Example 3 below, Lignin is an abundant, non-toxic natural polymer that is becoming increasingly more important due to its versatility in performance. Lignin sulfonate is an inexpensive by-product from pulp processing industries, and has already been used in a wide variety of products based on its dispersing, binding, complexing, and emulsifying properties. Although the exact structure of lignin is not yet known, a generalized chemical formula of a known portion of lignin sulfonate is shown in FIG. 3 .
In another embodiment, the template can be a micelle, thus resulting in an electrically conducting, water-soluble, high molecular weight polymer-micelle complex. Examples 4 and 5 below describe the preparation of polyaniline-dodecyl benzene sulfonic acid (DBSA) micelles and polyphenol-DBSA micelles, respectively. An important aspect of this embodiment is that micelles are spherically shaped with hydrophilic groups (i.e., charged head groups such as negatively charged benzene sulfonate) pointing out towards the aqueous-based solvent, and hydrophobic groups (i.e., tail groups such as dodecyl) pointing in towards the core of the micelle. Thus, monomers that align themselves upon the charged groups of the micelle template polymerize to form a spherical product.
The size (i.e., range of molecular weights) and uniformity of such spherical polymers can be easily controlled by adjusting the type of micelle template and the molar ratio of micelle to monomers. The molecular weight of the spherical polymeric products can reach as high as 10,000 kD. As mentioned above, it is critical for the head groups of a micelle template to be charged under the required reaction conditions for proper alignment of the monomers. Aside from DBSA, naphthalenesulfonic acid (pK a =0.57) bonded to a hydrophobic tail group can also be used as a template in this embodiment. A generalized micelle-assisted polymerization reaction (with aniline as the monomer) is illustrated in Scheme III below. Note that only a portion of the micelle is shown.
The novel polymer-micelle complexes can be used in a wide range of applications such as paints; coatings; emulsifiers in asphalt, pesticides, or pigments; sequestrants in water treatments; and dispersants for cement mixes, carbon black, and dust suppressants. The new methods also allow controlled entrapment of a variety of interesting molecular species such as various pharmaceuticals.
EXAMPLES
The invention is further described in the following examples, which do not limit the scope of the invention described in the claims.
Example 1
Preparation of Polyaniline-Sulfonated Polystyrene Complex
Horseradish peroxidase (HRP) (enzyme classification number (EC) 1.11.1.7), phosphate and Tris-HCl buffers were obtained from Sigma Chemicals Company, St. Louis, Mo. Aniline, sulfonated polystyrene (“SPS”) and hydrogen peroxide (30%) were obtained from Aldrich Chemicals, Inc., Milwaukee, Wis. All the chemicals were used as received.
The progress of a template-assisted polymerization reaction of aniline in the presence of the template, SPS (in a 1:1 ratio) was monitored by the change in visible absorbance. A Perkin-Elmer Lambda-9® UV-Vis-near IR spectrophotometer was used for the spectral characterization of the polymer. FIG. 4 shows the visible absorption spectra of the sulfonated polystyrene/polyaniline (SPS/PA) complex prepared under various pH conditions of 4, 6, 8, and 10. As shown in FIG. 4 , the SPS/PA complex, prepared at a pH of 4, exhibited a strong absorbance maximum at approximately 780 nm. This shows that the presence of an emeraldine form, i.e., an oxidized, electrically conducting form of polyaniline. Polymerization at higher pH resulted in an absorption maximum of about 600 nm, indicating a more insulating form of polyaniline. In all cases, the polymer complex did not precipitate out of solution, indicating that complexation of the polyaniline to the SPS had occurred.
Next, the molar ratio of monomer to polyelectrolyte template (repeat unit) was optimized. FIG. 5 shows a plot of absorption maxima for various SPS/aniline ratios. As shown, a ratio of 1:2, SPS/aniline was the minimum ratio required to obtain the electrically conducting form of polyaniline, which had an absorption maximum at approximately 780 nm at a pH in a range of between about 4 and about 5.
The reversible reduction/oxidation (redox) behavior of the SPS/PA complex was monitored by measuring visible absorption of the complex's under various pH conditions. In all cases, the polymer complex was prepared at pH 4.0 to obtain the electrically active form of the polyaniline. The pH of the solution was then adjusted for the absorption maxima measurements. As shown in FIG. 6 a , the SPS/PA complex shifted in absorption maxima to shorter wavelengths as the pH of the solution was increased. This indicated a reduction of the polyaniline backbone to a more insulating state. FIG. 6 b shows the reverse behavior where the absorption maximum was found to shift back to longer wavelengths with decreasing pH conditions. This indicated oxidation of the polyaniline backbone back to a more electrically conductive state. This redox behavior was reversible and confirms that an electrically active form of polyaniline was present in the final SPS/PA template complex. Molecular weight was determined by column chromatography using Protein PAK 300 SW®-Waters Association columns. Molecular weight of approximately 74 kD was measured indicating polymerization of the aniline and complexation to the SPS template.
The SPS/PA complex was self-assembled onto glass slides by the layer-by-layer electrostatic deposition technique (Ferreira, M., et al., Thin Solid Films, 244:806 (1995) and Decher, G., et al., Thin Solid Films, 210-211 (1992)). A glass slide treated with alkali (Chemsolv® alkaline) was exposed to polycation and polyanion solutions repeatedly to transfer monolayers of these polyelectrolytes for every exposure. A one mg/ml solution of poly(diallyl dimethyl ammonium chloride) (PDAC) at pH 2.5 was used as the polycation, while approximately a one mg/ml solution of SPS/PA at pH 2.5 was used as the polyanion. The glass slide was exposed to each polyelectrolyte solution for 10 minutes and washed with water at the same pH (2.5) to remove the unbound polymer from the surface. This process was repeated to obtain the desired number of layers.
FIGS. 7 a and 7 b show the visible absorption spectra of a film of fifty bilayers wherein PDAC layers alternate with SPS/PA layers, under various pH conditions. As shown in the figures, the multilayer film exhibited similar redox behavior as was observed previously with the solution absorption spectra. This result confirmed that facile electrostatic deposition was reasible with the SPS/PA polymer complex and that the electrical activity was maintained after deposition. In addition, multilayer and bulk films were prepared on indium tin oxide (ITO) slides and four-point probe conductivity measurements were taken. The results showed polymer-complex conductivities in the range of 10 −3 to 10 2 S/cm.
Example 2
Preparation of Polyphenol-Sulfonated Polystyrene Complex
Horseradish peroxidase (HRP)(enzyme classification number (EC) 1.11.1.7), phosphate and Tris-HCl buffers were obtained from Sigma Chemicals Company, St. Louis, Mo. Phenol, sulfonated polystyrene (SPS) and hydrogen peroxide (30%) were obtained from Aldrich Chemicals, Inc., Milwaukee, Wis. All the chemicals were used as received.
The monomer, phenol, was polymerized in a similar fashion as described in Example 1, with sulfonated polystyrene (SPS) in a 1:1 ratio. The progress of this reaction was monitored by the change in visible absorbance. Perkin-Elmer Lambda 9® UV-Vis-near IR spectrophotometer was used for the spectral characterization of the polymer. FIG. 8 a is a graph showing the visible absorption of polyphenol without SPS, versus phenol monomer. As shown, there was a significant absorption maximum in the visible spectrum upon polymerization, which indicates formation of polyphenol. However, with time the polymer began to precipitate out of solution. FIG. 8 b shows the visible absorption of polyphenol with SPS, versus phenol monomer. As shown again, there was a significant absorption maximum of the polymerized system in the visible spectrum. In this case, there was no observed precipitation of the polymer complex out of solution.
Molecular weight determination was carried out by column chromatography using Protein PAK 300 SW® columns manufactured by Waters Association. Molecular weight as large as 136 kD was measured, indicating polymerization of the phenol and complexation to the SPS template.
Example 3
Preparation of Polyphenol-Lignin Sulfonate Complex
Lignin sulfonate (Lignosol SFX-65, “LGS”) was purchased from Lignotech USA (Rothschild, Wis.). The sources of other starting materials have been stated above.
LGS was used as the template for the polymerization of aniline. 5.2 mg of LGS was dissolved in 10 ml of sodium monophosphate buffer (0.1 M) at pH 4.0. 180 μl of aniline was added to this buffer solution (final concentration=195 mM). 2 mg of horseradish peroxidase (“HRP”) was then added. 50 μl of hydrogen peroxide (0.025% solution) was added every 10 minutes, with constant stirring, until a total of 200 μl of hydrogen peroxide was added. The reaction was maintained at room temperature and was terminated after 12 hours. The solution was dialized using “spectra-pore” membrane bags (M w cut-off=1 kD) for 72 hours.
FIG. 9 is a graph showing overlapping visible absorption spectra of (1) LGS (indicated by - - - ); (2) polyaniline-LGS, HRP, and hydrogen peroxide (indicated by —— ); and (3) LGS and HRP (indicated by . . . . . ). Note that spectrum (2) significantly differs from spectra (1) and (3). The intense absorption peaks (at around 300 nm and 750 nm) as shown in spectrum (2) indicate the presence of the conducting or emeraldine salt form of polyaniline.
Example 4
Preparation of Polyaniline-Dodecyl Benzene Sulfonic Acid Micelle Complex
Dodecyl benzene sulfonate (DBSA) was purchased from Aldrich (Milwaukee, Wis.). The sources of other starting materials have been stated above.
Aniline (final concentration=3 mM) and DBSA (final concentration=10 mM) were dissolved in 10 ml of a sodium monophosphate buffer solution (0.1 M, pH 7.0) with horseradish peroxidase (HRP) (total concentration was 0.1-0.15 mg/ml). 100 μl of hydrogen peroxide (0.03%) were added to the solution.
The final products were dialized using centricon concentrators (10,000 cut off, Amicon Inc., Beverly, Mass.), dried under vacuum at 50° C., and dissolved in water for further analysis.
FIG. 10 is a graph showing overlapping visible absorption spectra of (1) polyaniline-dodecyl benzene sulfonic acid (DBSA) micelle prepared at pH 4.0, (indicated by —— ); (2) polyaniline-DBSA micelle prepared at pH 4.0 and adjusted to pH 10.0 (indicated by - - - ); and (3) DBSA micelle and aniline (indicated by —— ——. Note that the spectrum of reaction mixture (1) differs significantly from that of reaction mixture (3) (i.e., the control), showing a strong and broad absorption above 800 nm which indicates the presence of the conducting form of polyaniline. After polymerizing at pH 4.0 (see spectrum (1)), the pH of reaction mixture was adjusted to pH 10.0 (see spectrum (2)), the absorption peaks shifted to 600 nm which indicates the polymer became less conductive. The results reflect the pH dependence of the complex.
Example 5
Preparation of Polyphenol-Dodecyl Benzene Sulfonic Acid Micelle Complex
67 mg of phenol (71.3 mM) and HRP (total concentration=0.1-0.15 mg/ml) were dissolved in 10 ml of a sodium monophosphate buffer solution (0.1M, pH 7.0) in the presence of equimolar DBSA (i.e., 71.3 mM) at room temperature. A total volume of 0.024 ml of hydrogen peroxide (71.3 mM) was added to the solution (about 10 mM added every 5 minutes). The final product (yield was 93.9%, by weight) was dialized using centricon concentrators (10,000 cut off, Amicon Inc., Beverly, Mass.), dried under vacuum at 50° C., and then dissolved in DMSO/water (50/50) solution for further analysis. The molecular weight of the product was determined to be 3.5×10 6 g/mol. A control experiment was conducted by using denatured enzyme. HRP was denatured by boiling in a 0.1 M sodium monophosphate buffer (pH 7.0) for 30 minutes. The boiled HRP was tested using purpurogallin, and was found to be inactive. No polymerization was observed with the control experiment.
FIG. 11 is a graph showing overlapping visible spectra of (1) polyphenol-DBSA micelle (indicated by —— ); and (2) phenol monomer and DBSA micelle (indicated by - - - ) Note that spectrum (1) differs significantly from spectrum (2), showing a strong broad absorption above 600 nm and reaching pass 900 nm. This result indicates the presence of the polyphenol complex in the first reaction mixture.
Other Embodiments
It is to be understood that while the invention has been described in conjunction with the detailed description thereof, the foregoing description is intended to illustrate and not limit the scope of the invention, which is defined by the scope of the appended claims. Other aspects, advantages, and modifications are within the scope of the following claims. For example, water-soluble polymers formed by the novel polymerization method can be precipitated from solution by adjusting the pH with a suitable acid or base.
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The invention relates to a novel method for enzymatic polymerization which includes (1) obtaining a reaction mixture including a monomer, a template, and an enzyme; and (2) incubating the reaction mixture for a time and under conditions sufficient for the monomer to align along the template and polymerize to form a polymer-template complex. The template can be a micelle, a borate-containing electrolyte, or lignin sulfonate. Such a complex possesses exceptional electrical and optical stability, water solubility, and processibility, and can be used in applications such as light-weight energy storage devices (e.g., rechargeable batteries), electrolytic capacitors, anti-static and anti-corrosive coatings for smart windows, and biological sensors.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuing application, under 35 U.S.C. §120, of copending International Application No. PCT/AT2005/000112, filed Mar. 31, 2005, which designated the United States; this application also claims the priority, under 35 U.S.C. §119, of Austrian Patent Application No. A 651/2004, filed Apr. 15, 2004; the prior applications are herewith incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The invention relates to a lid for closing containers being based on an at least two-layered composite assembly and having an opening aid. An assembly layer facing the container seals against a container edge and forms an opening, which is produced when the assembly layers are separated, for removal of package contents located in the container. The invention also relates to a method for producing the lid.
[0003] It is known to use at least two-layered lids for closing containers in order, for example, to make the aroma protection required for food possible.
[0004] It has furthermore been found that, in particular in the case of perishable foods, the consumer has an increased need for information with regard to origin, ingredients and keepability. In order to provide sufficient space for that information, it is nowadays printed on the outer layer of the two-layered lid, while the inner layer as far as possible remains unprinted. That is also because possible contact of printing inks with the foods is to be avoided.
[0005] The above-mentioned two-layered lids also have increased aroma protection when a removal opening is provided in that layer of the lid facing the package contents. That is preferably effected by providing weakening lines which are exposed when the package is opened, that is when the lid layers are separated from one another. Pressing-in those weakening lines produces a removal opening through which package contents can be completely or partly removed. It is advantageous in large packages, in particular if the outer lid layer is provided with a pressure-sensitive adhesive on its inner side, for example, in order for it to be possible to close the removal opening again.
[0006] Those packaging devices nevertheless have the disadvantage that the weakening lines in the lid layer facing the package contents define a potential defect location, in particular when the outer layer of the lid is damaged during transport, for example, and moisture or possibly impurities in the form of bacteria can thus find its or their way into the package contents through the weakening lines. Furthermore, in particular aluminum foils display the characteristic of undesirable corrosion in the region of the weakening lines.
SUMMARY OF THE INVENTION
[0007] It is accordingly an object of the invention to provide a lid with a removal opening for closing containers and a method for producing the lid, which overcome the hereinafore-mentioned disadvantages of the heretofore-known devices and methods of this general type for at least two-layered lids for closing containers, while at the same time providing a removal opening in the lid to which the consumer can gain access in a simple way, preferably upon opening a package.
[0008] With the foregoing and other objects in view there is provided, in accordance with the invention, a lid for closing a container having a container edge. The lid comprises a composite assembly having at least two continuous assembly layers and an opening aid in an opening aid region. The at least two assembly layers include an assembly layer facing the container and an assembly layer facing away from the container. The assembly layer facing the container seals against the container edge and forms a removal opening produced by separating the assembly layers for removal of package contents located in the container. The assembly layer facing the container has an assembly adhesion to the assembly layer facing away from the container. The removal opening defines a removal opening lid region and a remaining lid region. The assembly layer facing the container is made mainly of a plastic having an intrinsic tearing resistance being lower in the removal opening lid region than the assembly adhesion to the assembly layer facing away from the container in the remaining lid region. The plastic of the assembly layer facing the container has an assembly adhesion to the container edge being greater at least in the opening aid region than the assembly adhesion to the assembly layer facing away from the container.
[0009] With the objects of the invention in view, there is also provided a method for producing a lid, which comprises subjecting the composite assembly formed of the layers to increased pressure and increased temperature in a predetermined region for increasing the assembly adhesion between the assembly layers in the predetermined region in comparison with a remaining lid cross section.
[0010] With the objects of the invention in view, there is additionally provided a method for producing a lid, which comprises induction welding the assembly layers in a predetermined region to bring about increased assembly adhesion between the assembly layers in the predetermined region in comparison with a remaining lid cross section.
[0011] With the objects of the invention in view, there is furthermore provided a method for producing a lid, which comprises ultrasonic welding the assembly layers together in a predetermined region to bring about increased assembly adhesion between the assembly layers in the predetermined region in comparison with a remaining lid cross section.
[0012] With the objects of the invention in view, there is concomitantly provided a method for producing a lid, which comprises connecting the assembly layers with a bonding agent having latent cross-linking accelerators. The assembly layers are then subjected to increased pressure and/or increased temperature in a predetermined region for initiating a cross-linking reaction by the accelerators to achieve increased assembly adhesion in the predetermined region in comparison to a remaining lid cross section.
[0013] The effect of this construction and method is that the plastic present in the assembly layer facing the container adheres so strongly to the outer assembly layer in the region of the removal opening, that a region corresponding to the removal opening is torn out when opening takes place, while the remaining layer of the lid, which faces the container, continues to adhere to the container edge through the sealing action in relation thereto. In order to ensure that the consumer can gain access to the package contents through the removal opening in a simple way, the consumer takes hold of the lid by its opening aid and peels the layer facing away from the container off the plastic layer below. The force applied breaks the plastic layer from the container edge at least in the region of the opening aid so that the container remains partly closed, with the exception of the removal opening.
[0014] Furthermore, the risk of impurities possibly finding their way in is avoided in the unopened state since the material layers are themselves continuous, that is no weakening lines at all are provided for forming the potential removal opening.
[0015] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0016] Although the invention is illustrated and described herein as embodied in a lid with a removal opening for closing containers and a method for producing the lid, 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.
[0017] 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
[0018] FIGS. 1A to 1 F are fragmentary, sectional views of possible embodiments of a lid according to the invention;
[0019] FIGS. 2 to 4 are fragmentary, sectional views illustrating possible variant methods for producing a region of increased assembly adhesion within the lid; and
[0020] FIGS. 5 and 6 are perspective views showing the use of the lid according to the invention for closing a container.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] Referring now in detail to the figures of the drawings as a whole, it is seen that in order to produce a lid 1 according to the invention, mainly plastics, in the form of either monopoly or multiply layers, are used as an assembly layer 2 , that is as that assembly layer of the lid facing a container 17 seen in FIGS. 5 and 6 . The assembly layer 2 made of plastic has a thickness in a range of 6 to 100 μm, for example. The plastics used are provided mainly from the group of polystyrenes, polyethylenes, polyesters and polypropylenes, corresponding copolymers, as well as their mixtures. The plastics themselves can be filled or unfilled, and talc, silica or chalk are advantageously used as fillers.
[0022] A particularly advantageous embodiment of the lid according to the invention is obtained if the plastic layer 2 facing the container is sealed against a container edge 17 ′ of the container 17 . This makes it possible to dispense with an additional sealing medium, for example in the form of a sealing lacquer, as is illustrated in FIG. 1E .
[0023] Furthermore, the assembly layer 2 facing the container can be provided, if appropriate, with an informative imprint on its outer side, that is the side facing the consumer during peeling.
[0024] An assembly layer 3 facing away from the container is made from an aluminum foil with a thickness of 10 to 100 μm, for example. However, it is also conceivable to use a plastic film of increased strength and, if appropriate, to combine it with aluminum or paper on its outer side.
[0025] A peelable assembly for the lid 1 is produced after selection of the materials for the layers 2 and 3 . This is effected by coextrusion, for example, which has particular advantages when plastics are used in both the layer 2 and the layer 3 . Furthermore, it is possible to apply the layer 2 to the layer 3 by extrusion coating. This is effected in such a way that the plastic of the layer 2 is extruded onto the layer 3 and is then connected to it in such a way that the peelability of the layers 2 and 3 is maintained.
[0026] It is furthermore conceivable to produce the assembly formed of the layers 2 and 3 by laminating. This can take place with or without addition of bonding agents, depending on the type of plastic and/or its content of copolymers.
[0027] After production of the peelable assembly for the lid 1 , it is printed and, if necessary, provided with a sealing medium. In this connection, as is seen in FIG. 1E , a conventional sealing lacquer 7 is applied to that side of the plastic layer 2 facing the container 17 , and it is advantageous to construct it with a rough surface in order to considerably ease unstacking of the lids 1 which are usually stored one above another in magazines. A rough-surface structure in the form of geometrically disposed rough-surface spacers 7 ′ seen in FIG. 1F is especially advantageous.
[0028] Furthermore, a printing lacquer 6 on the outer assembly layer 3 , as is seen in FIGS. 1C and 1D , can also have a rough surface in order to additionally ease unstacking and, if appropriate, achieve a particular printing decoration. In this connection, the printing lacquer 6 is advantageously provided in the form of geometrically disposed spacers 6 ′ seen in FIG. 1D . In order to more precisely mark a region 4 in which assembly adhesion between the layers 2 and 3 is increased in comparison with a remaining lid region, it can have a smooth, informative printed representation in its surface structure in the same way in order to indicate to the consumer the possibility of partial removal through a removal opening which will be produced in the region 4 .
[0029] In order for it to then be possible to provide the region 4 of increased assembly adhesion between the layers 2 and 3 , which will also correspond to a shape of a removal opening 19 as shown in FIG. 5 , the following methods are available, for example:
[0030] According to the illustrations in FIGS. 2 and 3 , production of the region 4 of increased assembly adhesion takes place according to what is known as a roller principle. In this connection, rollers 8 or 10 are provided with raised portions 8 ′ and 10 ′ on their surface. The rollers themselves are heated to a temperature of between 100 and 300° C.
[0031] According to FIG. 2 , the assembly formed of the layers 2 and 3 is guided through between the roller 8 and a roller 9 . Bearing pressure of the rollers in the nip and provision of the raised portions 8 ′ produces the region 4 of increased assembly adhesion, as is indicated diagrammatically in FIG. 1A , for example.
[0032] According to FIG. 3 , in order to increase dwell times, a heated drum is provided as the roller 10 , on the surface of which the assembly layers 2 and 3 are guided by guide rollers 11 . The shape and size of the drum and the raised portions 10 ′ provided thereon make it possible to increase the dwell times considerably in comparison with the guidance according to FIG. 2 . The assembly layers 2 and 3 are subjected to the pressure of the drum roller, in particular of the raised portions 10 ′, over a wide area, by virtue of pressing rollers 12 , so that particularly strong assembly adhesion, that is virtually welding together of the assembly layers 2 and 3 , can be achieved in the region 4 .
[0033] FIG. 4 shows that the production of the region of increased assembly adhesion can also be carried out continuously during punching out of material present in roll form into the individual lids. In this connection, the assembly layers 2 , 3 are guided through as roll material between a punching tool 13 and a heated plate 14 , the punching tool 13 is lowered onto the layer 3 and at the same time, by virtue of the heated plate 14 , the two layers 2 and 3 are welded together through the layer 3 . This makes it possible to achieve increased assembly bonding as provided in the region 4 and immediately afterwards, with the aid of a conventional punching tool 15 which punches the assemblies still present as roll material, as shown in FIG. 1A , for example, into the individual lids, that can be removed through an outlet opening 16 .
[0034] If the assembly layers 2 and 3 are made of thermoplastic materials, however, they can be heated until liquid and pressed together under pressure in a predetermined region, preferably the region 4 of increased assembly adhesion to be formed. This is effected by ultrasonic or induction welding, for example.
[0035] It is furthermore possible to apply a bonding agent to which latent cross-linking accelerators have been added between the layers 2 and 3 by conventional laminating methods. When predetermined regions of this assembly are subjected to increased pressure and increased temperature, this initiates a cross-linking reaction so that increased assembly adhesion in comparison with the remaining lid cross section is achieved in this predetermined region 4 .
[0036] The assembly adhesion, which is increased in the region 4 , is then measured by using the average peeling force necessary for separating the assembly layers 2 and 3 . In this connection, a specimen formed of the assembly layers 2 and 3 is produced, which is 15 mm wide in the running direction and approximately 300 mm long in the longitudinal direction. The assembly layers 2 and 3 are then separated from one another at their ends by hand and clamped into a clamping configuration of a tension testing device, for example one from the company Zwick. Further testing is effected at a pull-off rate of 100 mm/min, a clamping length of maximally 50 mm and a pull-off angle of 90°. The measurement result, or the profile of the peeling resistance, corresponds to an assembly adhesion measurement and is recorded either on the tension testing device itself or with a diagram recorder. Average values in N/15 mm are calculated from the measurement results of the tests. This reveals that measurement values of >5 N/15 mm to a maximum of 160 N/15 mm are achieved in the region 4 of increased assembly adhesion, that is the assembly adhesion in the region 4 is so great that upon opening, as shown in FIG. 5 , part of the assembly layer 2 is “torn out” and, due to the increased assembly adhesion, continues to adhere to the layer 3 as a partial region 2 ′.
[0037] On the other hand, in a remaining container cross section, an assembly adhesion of 0.1 to 5 N/15 mm is present, noting that a “comfortable peeling force” for the consumer is provided by assembly adhesion in a range from 0.2 to 0.4 N/15 mm. This assembly adhesion is also lower than that between the layer 2 and the container edge 17 ′ so that the layers 2 and 3 can be separated (peeled) from one another in a simple way in the remaining lid region. This operation is explained below with reference to FIG. 5 :
[0038] In this connection, an opening aid 18 in the form of a grip or pull tab is pulled in the direction of an arrow F so that the layers 2 and 3 are separated (peeled) from one another by the force being applied. Due to the increased assembly adhesion in the region 4 (see FIG. 1A ), the layer 2 ′ is then torn out of the plastic layer 2 , corresponding to the size of the removal opening 19 , in such a way that it continues to adhere to the layer 3 , that is to the assembly layer facing away from the container, due to the increased assembly adhesion. Furthermore, the force being applied breaks the plastic layer 2 from the container edge 17 ′ at least in the region of the opening aid 18 so that the container remains partly closed, with the exception of the removal opening. The container 17 consequently remains mostly closed by virtue of the seal seam strength between the container edge 17 ′ and the layer 2 , and the package contents, such as a yogurt drink or even spices, can be removed through the removal opening 19 .
[0039] However, if only part of the package contents is to be removed and the container is then to be reclosed at least loosely, the assembly layer 3 facing away from the container is advantageously provided with a pressure-sensitive adhesive 20 . As is shown in FIG. 6 , the container 17 is opened by pulling off the lid 1 in the direction of the arrow F so that the package contents can be removed in part. Then, the layer 3 is again placed over the assembly layer 2 remaining after opening in the direction counter to the arrow F and pressed at least lightly onto it, so that the adhesive effect of the pressure-sensitive adhesive 20 can be exerted. The pressure-sensitive adhesive 20 can also be present in the region of the grip tab 18 so that the grip tab can be fixed by folding it over the container edge 17 ′, which improves the reclosability of the container 17 overall.
[0040] In summary, an illustrative embodiment of the invention can be represented as follows:
[0041] According to the invention, a lid 1 is indicated, which is formed substantially of the assembly layers 2 and 3 , with the assembly layer 2 facing the container being made continuously, that is without any weakening lines, of a plastic of which the intrinsic tearing resistance is lower in the region of a potential removal opening than its adhesion to the outer assembly layer 3 , that is to the layer facing away from the container. This leads to a partial region 2 ′ of the layer 2 corresponding to the removal opening 19 being torn out when the layer 3 is peeled off from the layer 2 lying below it with the opening aid 18 , whereas the remaining assembly layer continues to adhere to the container edge 17 ′. Furthermore, the force applied during peeling-off breaks the plastic layer 2 from the container edge 17 ′, at least in the region of the opening aid 18 , so that the container remains partly closed, with the exception of the removal opening. This effect is achieved by specific adjustment of the assembly adhesion on one hand between the layers 2 , 3 of the lid element and on the other hand between the container edge 17 ′ and the layer 2 facing the container. The assembly adhesion is thus increased in the region 4 of the potential removal opening 19 in comparison with the assembly adhesion present between the layers 2 and 3 . However, it is at least the same as that assembly adhesion between the layer 2 facing the container, that is that assembly adhesion which brings about the seal seam strength between the inner lid layer 2 and the container edge 17 ′. This means that while it is true that a removal opening 19 is formed when the layers 2 , 3 are separated from one another, the inner layer 2 nevertheless continues to adhere mostly to the container edge 17 ′. This makes it possible for package contents also to be removed in part and for the container to be reclosed at least partly after their removal.
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A lid for closing containers includes an at least two-layered composite assembly. A layer facing the container seals against a container edge and forms an opening by layer separation, for removing contents. The layers have a continuous construction without weakening lines. The layer facing the container is made mainly of a plastic having an intrinsic tearing resistance being lower in the region of the opening than its adhesion to the layer facing away from the container in a remaining region and an adhesion to the container edge being greater at least in the region of an opening aid than to the other layer. The plastic adheres so strongly to the outer layer in the region of the opening that a region corresponding to the opening is torn out upon opening and a remaining layer of the lid facing the container continues to adhere to the container edge by sealing action.
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BACKGROUND OF THE INVENTION
A. Field of the Invention
The present invention relates to door and window hardware. More particularly, the present invention relates to a mechanically stable and ergonomically improved door and window sash lock.
B. Description of the Prior Art
Sliding windows or patio doors in a building are made for letting in necessary light and air into the room while allowing occupants to have a comfortable viewing of the surrounding nature. At the same time, such doors or windows should be able to lock out harmful elements and potential intruders.
Window latches and locks that are also applied to doors have been developed as the windows in the modernized buildings have long been evolved all together. Of different types of slider window, a single-hung type window is structured to have an upper outside pane in a stationary sash and an inside pane in a sliding sash guided in a window frame along its vertical path between a raised level positioned over the upper sash to half open the window and a lowered position to close the window opening in cooperation with the upper sash. A double-hung type window has two vertically sliding sashes movable in parallel planar paths in a single frame. There are also horizontal sliders. A gliding window has two sashes with at least one sliding horizontally past the other. The respective sashes of the double-hung windows may be made to swing inwardly for the purpose of a safe cleaning but they must be returned to their vertical abutting positions when the window is to be locked. Normally, in the closed position, the mating sashes have the respective proximal sides overlapped to offer the necessary sealing. Therefore, most latches are conveniently positioned near the meeting areas of the two sashes at the exposed surface of the inner sash while the mating keeper or strike is fixed to the accompanying outer sash.
Known latches for windows have their inherent drawbacks. Automatic window sash locks as depicted in U.S. design Pat. No. 395,222 to Fountaine comprise a main latch body attached to a slide-open sash for automatically engaging a fixed keeper on the companion sash or the sash itself that incorporates in its profile a notch so that the sashes are immobilized in the frame when the window is closed. Such sash locks generally include a user-operated component handle to release the automatic locking mechanism, which only needed the sliding closure of the sash to push in a bolt of the sash lock before it protrudes back into engagement with the keeper or notch. To streamline the one-handed user operation in lift or sideway slide opening of the window, the release handle or lever of the sash locks is adapted to be depressed by index to little fingers while the thumb presses on the underside of the proximal sash part to release the lock and slide the sash in one action.
However, the lever needs a substantial projection from the main latch body taking up space upward as well as toward the user for the bolt to create a proper lever or bolt action inside the latch device. This makes a bulky and unappealing lock structure that sticks into the viewing area of glass panes. Under the superficial problem lies a mechanical disadvantage to have to apply a large circular force to retract a locking bolt out of engagement with the counterpart of the other sash. For the internal actuator to move the bolt easily, the lever must extend above and beyond the latch device itself as long as possible. However, such deflecting lever movements produce a long-term adverse force against the secure joint between the latch device and sash during their combined lifetime because normally there is only a couple of fasteners to endure the releasing depressions at repeated window openings.
Hence, there is need for a small form factor sash lock that is not only visually unobtrusive but also mechanically stable and ergonomically fit.
SUMMARY OF THE INVENTION
In view of the foregoing, the object of the preset invention is to provide a compact sash lock that locks automatically and is squeezable directly over almost its entire body to actuate the release mechanism requiring no defecting actuators or handles.
Another object of the present invention is to provide a fail-safe locking mechanism for door and window sashes which is easy to manufacture.
A sash lock of the present invention is for use with door and window sashes and it has a base housing having an elongated planar bottom with two tubular posts located near further lateral ends of the bottom to support fasteners for mounting the sash lock on a first inner sash member sliding in relation to a second outer sash member. Around the bottom of base housing an upright front wall with an elongated aperture and connecting side and rear walls encircle and a supporting topography is integrally formed inside of the walls.
A plunger is slidably supported in the base housing to move linearly under a forward bias and has cam surfaces at a rear end facing forwardly and a beveled lip portion at a front end protruding through the front aperture of the base housing.
A large button block extends laterally over the tubular posts of the base housing and has a beveled surface facing the cam surfaces of the plunger and two opposite end tunnels to fit snugly over the tubular posts for maintaining linear translations perpendicular to the moving direction of the plunger under an expansive bias for normally pushing the button block away from the base housing in cooperation with the biased counteraction of the cam surfaces of the plunger. The button block has a height greater than that of the surrounding walls of base housing. Then, a top housing is fastened to the base housing to enclose the plunger and button block allowing them to move within the respective ranges of translation.
The sash lock further comprises two identical holes formed in the bottom of base housing at both sides of the aperture and a separate keeper for mounting on the second outer sash member. The keeper has a strike plate that extends in parallel with the front wall of base housing when it is mounted on the outer sash member, a beveled surface at a distal edge of the strike plate to face the beveled lip portion of the plunger, two opposite legs at a proximal edge of the plate to define a large rectangular notch into which the plunger protrudes, an L-shaped bracket joined to distal ends of the legs for supporting fasteners threaded though the second sash member and a double catch shaped to hook in the two bottom holes of the base housing as the plunger rides over the strike plate at the meeting of their beveled surfaces. Therefore, the lock can make a complete three dimensional locking engagement with the keeper until an inside occupant of the inner sash member gently grabs the inner sash and the button together to release the plunger and start sliding the sash at the same time.
The forward bias of the plunger and the perpendicular expansive bias of the button block are produced by two pairs of identical helical springs held in the respective positions at first ends by topographic peaks and valleys of the base housing and complementary protrusions of the top housing and at the opposite second ends through insertion into slots formed in the plunger and the button block to keep a balanced actuation of the button block and plunger.
The plunger is kept in fore and apt translations in one plane by two side upright walls from the base housing and in another perpendicular plane by a flat area of the base housing bottom and complementary guide plates from the top housing.
Embodiments of the invention will now be described by way of example with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation view of a compact sash lock installed according to the present invention.
FIG. 2 is an exploded perspective view of the sash lock of FIG. 1 showing all of the components.
FIG. 3A is an enlarged perspective view of the latch unit with an upper housing removed to show in detail the positional relations of components within a base housing.
FIG. 3B is a perspective view of the upper housing to mate with and close the base housing.
FIG. 4 is a cross sectional view along the frontal median lines of the keeper and latch unit of FIG. 2 after assembly.
Similar reference numbers denote corresponding features throughout the attached drawings.
16 Upper Sash 12 Window 38 Glass Pane 34 Beveled Surface 10 Sash Lock 22 Button 11 Latch Unit 36 Double Catch 14 Lower Sash 20 Seal 42 Lip 24 Meeting Rail 44 U-Shaped Interlock 24 Groove 94 Screw 82 Upper Housing 88 Mounting Post 90 Vertical Tunnel 50 Base Housing 92 Guiding Post 86 Assembly Screw 26 Plunger 132 Strike Plate 134 Leg 32 Keeper 140 Screw Slot 136 Notch 138 L. Bracket Portion 112 Bump 102 Push Blade 108 Tip 99 Block Section 100 Blind Hole 91 End Leg 54 Upright Wall 74 Beveled Surface 62 Lip Portion 68 Aperture 64 Stop 70 Hole 66 Front Wall 84 Screw Hole 52 Bottom 128 Sidewall 50 Base Housing 96 Spring 76 Spring 80 Block 98 Column 130 Rear Wall 82 Upper Housing 188 Recessed Wall 106 Opening 126 Lip 122 Guide Plate 60 Cam Surface 58 Foot 124 Stake 120 Recessed Wall 116 Bump 140 Screw Slot
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIG. 1 , a window lock assembly 10 of the present invention generally comprises a latch unit 11 and a keeper 32 and is made for a sliding window 12 that may includes a rectangular inner lower sash 14 shown at its top cross sectional area and a similarly shaped outer upper sash 16 shown at its bottom cross sectional area for mating with the lower sash 14 to close window 12 as the lower sash 14 slides over the upper sash 16 in a window frame (not shown). Lower sash 14 encases downwardly extending glass panes 18 and a sealing 20 between the panes 18 . In the window 12 illustrated, latch unit 11 may be mounted on the top middle surface of lower sash 14 .
Besides covering the interior room of a building from the elements, window 12 may obtain an improved security and aesthetic value from the sash lock 10 that may be installed initially at the time of building a house or home improvements wherein the owner may replace the old bulky locking devices with this mechanically reliable and yet more compact sash lock 10 . With functionally and ergonomically advanced quality, the installed sash lock 10 will blend well with the surrounding window sashes and does not create a physical interference with handling the sashes in opening and closing the window while allowing an uninterrupted view due to its low and thin profile lodged within a small confinement between the two sashes 14 and 16 . With the complete renovation from the known cam lock mechanisms, lock assembly 10 of the present invention has come to have no conventional deflected lever projection any more. Instead, it provides an oversized push button 22 to be depressed directly toward lower sash 14 in its longitudinal direction so that the user intuitively grabs button 22 together with the underlying sash 14 to lift the same in the normal course of opening the window 12 . No extra manipulations to release sash lock 10 are necessary. Because button 22 is depressed within the area of latch unit 11 of the sash lock 10 and in direct alignment with lower sash 14 the attachment of latch unit 11 to sash 14 stays firm over long time.
Facing opposite to lower sash 14 , the upper sash 16 has a horizontal upper groove 24 for receiving a spring-loaded plunger 26 of latch unit 11 through the interlocking keeper 32 , which is affixed into groove 24 and provides a beveled surface 34 for interacting with plunger 26 and a double catch 36 for immobilizing latch unit 11 and lower sash 14 completely.
Upper sash 16 may be stationary encasing upwardly extending glass panes 38 and a sealing 40 between the panes 38 although mechanisms are known to inwardly swivel and/or slide up down both sashes 14 and 16 . In the double-hung type window 12 illustrated, latch unit 11 may be mounted on the top middle surface of lower sash 14 . Along the outer side of lower sash 14 extends a downward lip 42 for mating with a U-shaped interlock 44 of the meeting rails made of sashes 14 and 16 in order to provide the preliminary security as well as weather sealing. The plunger 26 may be made of zinc. The metallic plunger 26 has a hardness, which provides wear-resistance to the repeated engagement with keeper 32 or the upper sash 16 at the groove 24 in case keeper 32 is not present.
FIG. 2 depicts the overall construction of latch unit 11 and its interlocking keeper 32 . A major component of latch unit 11 is a base housing 50 that may be made of a die-cast metal in the shape of a generally rectangular crib having various anchor means for holding moving parts in the latch unit 11 .
The housing 50 and the rest associated parts constituting latch unit 11 are formed symmetrical with reference to the frontal meridian line (not marked) of the unit 11 in order to keep balanced latching actions in cooperation with the similarly symmetrical keeper 32 . Mounted on the bottom 52 of base housing 50 is the twin cam plunger 26 adapted to slide horizontally through housing 50 within a straight track formed by two side upright walls 54 distanced equally from the meridian line of unit 11 as better shown in FIG. 3A .
Plunger 26 is generally U-shaped with two legs 56 extending toward the interior of housing 50 and terminated by feet 58 , respectively. Each of the feet 58 has a top cam face 60 to be actuated by a vertical downward depression to provide a retracted position of plunger 26 . The feet 58 of plunger 26 are connected by a lip portion 62 , which is movable between an extended position shown in FIG. 2 and the same retracted position of plunger 52 . Extension of plunger 26 is limited by two opposite side stops 64 integrally formed to plunger 52 for abutment at the inner surface of a front upright wall 66 of housing 50 . To allow the protrusion of lip portion 62 , front wall 66 has a vertical rectangular aperture 68 centrally positioned. Identically formed in bottom 52 at both sides of aperture 68 are horizontal rectangular holes 70 for accepting vertical double catch 36 of keeper 32 to provide an omni-directional locking engagement between unit 11 and keeper 32 that is very difficult to break. In order to take advantage of double catch 36 combined with rectangular holes 70 , latch unit 11 may be fastened to sash 14 slightly overhanging as illustrated in the drawings.
The top surfaces of plunger 26 are flat save cam faces 60 and a selected cutout 72 that reduces the weight of plunger 26 . Of the bottom surfaces of plunger 26 , lip portion 62 has a beveled surface 74 around its lower front corner for cooperating with the corresponding surface of keeper 32 . Then, two expansion springs 76 are inserted into the legs 56 through bores 78 that extend almost the length of the legs 56 , respectively as shown in cross section in FIG. 4 . The outer free ends of springs 76 are each kept in place by a couple of small blocks 79 and 80 formed integral to housing 50 at side-by-side positions. An upper housing 82 for closing base housing subsequently closes the top open space between blocks 79 and 80 as will be described below. Therefore, twin cam plunger 26 is always urged outwardly to protrude into engagement with keeper 32 when they slide into a meeting position.
In addition, two screw holes 84 are formed in bottom 52 near its lateral edges to permit two assembly screws 86 to be respectively driven up to downwardly extending mounting posts 88 , which are integrally formed on upper housing 82 to permanently enclose the various components of latch unit 11 within a partially closed space between the two housing members 50 and 82 .
The separately formed button 22 is responsible to activate plunger 26 by pushing back the cam faces 60 . Button 22 may be made of a single metal block spanning almost the entire length of the housing 50 or 82 . Button 22 is elongated laterally and relatively higher than wall 66 of base housing 50 . In addition, button 22 has twin vertical tunnels 90 through its opposite end legs 91 for snuggly receiving two upright guiding posts 92 that double as screw supports for two mounting screws 94 , which can be easily driven from above the completed sash lock 10 through posts 92 and then into lower sash 14 . Each post 92 may have a funnel-shaped top surface to conform to the conical surface of screw 94 for a firm engagement.
At the same time, button 22 is held in a balanced posture by two upright suspension springs 96 , which are anchored on round columns 98 formed on housing bottom 52 inwardly of guiding posts 92 . The combined expansive force of springs 96 is determined to be just enough to counter the gravity at button 22 plus a relaxed exertion of manual push to ensure a pleasant manual actuation of button 22 as well as the uninterrupted automatic advancement of plunger 26 into the locking position by the horizontal plunger springs 76 .
Button 22 also has left and right block sections 99 with respective blind holes 100 formed concentrically to columns 98 for holding upper portions of springs 96 so that springs 96 are secured between base housing 50 and button 22 , which are always urged away from each other. Extending lengthwise underside of button 22 is a push blade 102 beveled for engaging both cam surfaces 60 at the same time to retract plunger 26 when button 22 is depressed.
Additionally, in the front middle area of button 22 there is formed a stern 104 that conveniently enlarges the area of button 22 to be contacted by the operator's hand and helps assist button 22 in maintaining its vertical translations along the guiding posts 92 as stem 104 keeps sliding contacts with upper housing 82 through its large opening 106 that conforms to the general circumferential profile of button 22 as shown in FIG. 3B . Stem 104 gradually converges and is bordered by a blunt tip 108 with round sides 110 that altogether extend vertically downwardly. Preferably, stem 104 is hollow to keep button 22 light.
Button 22 has two side bumps 112 on its front vertical walls 114 ( FIG. 3A ) and a similar middle bump 116 at its rear lower edge ( FIG. 4 ) in order to limit its upward translation by abutting the respective recessed walls 118 formed on upper housing 82 near the front section of opening 106 and a similar recessed wall 120 located at the same height of walls 118 close to the rear middle section of opening 106 .
The thus constructed button 22 can hold itself in the assembled position in base housing 50 while the respectively spring loaded plunger 26 and button 22 are both encased by upper housing 82 , which is secured using the assembly screws 86 . Depending from the bottom surfaces of button 22 are a pair of guide plates 122 for holding down legs 56 of plunger 26 and another pair of rear stakes 124 to run over springs 76 placed between the open blocks 79 and 80 to secure the distal ends of springs 76 . In order to facilitate assembly of upper housing 82 onto base housing 50 , upper housing 82 has an alignment means of discrete downward lips 126 along the lower peripheral surfaces to fit snugly in the interior of surrounding walls of base housing 50 which comprises front wall 66 , two side walls 128 and a rear wall 130 .
Keeper 32 comprises an upright strike plate 132 having beveled surface 34 at the top edge and two opposite legs 134 a , 134 b at the bottom to define a large rectangular notch 136 into which plunger 26 clicks to keep latch unit 11 in a locked position automatically after plunger 26 rides over strike plate 132 at the meeting of their beveled surfaces 74 and 34 . Extending integrally from the bottom of strike plate 132 is an L-shaped bracket portion 138 with at least two screw slots 140 for fastening plate 132 to upper sash 16 shown in FIG. 1 . Screw slots 140 are carefully positioned in bracket portion 138 to permit unobstructed access of fastening screws through notch 136 at installation.
The double catch 36 comprises two upturned hooks stemming from legs 134 a and 134 b . When latch unit 11 goes into the locked position, double catch 36 comes to penetrate into the holes 70 of base housing 50 in order to further lock the unit 11 and sash 14 horizontally over the primary vertical latching engagement of plunger 26 . Therefore, latch unit 11 can make a complete three dimensional locking engagement with keeper 32 until an inside occupant of the window 12 gently grabs the lower sash 14 with button 22 to release plunger 26 and start sliding the sash 14 at the same time.
Therefore, while the presently preferred form of the sash lock has been shown and described, and several modifications thereof discussed, persons skilled in this art will readily appreciate that various additional changes and modifications may be made without departing from the spirit of the invention, as defined and differentiated by the following claims.
For example, as a matter of simply changing the orientation, the same sash lock 10 may be mounted to a laterally sliding sash door at the interior side following the illustrated mounting method in order to obtain the equally improved benefit of the present invention.
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A sash lock for use with door and window is provided. The lock has a base housing shaped into a laterally extending crib to contain a partially protruding plunger sliding under a forward bias, a large button block that occupies a substantial area at the top of the lock to allow for a unique squeeze release of the plunger and translates in a perpendicular plane with respect to the plunger movement under an expansive bias for normally pushing the button block away from the base housing in cooperation with the biased counteraction of the cam surfaces of the plunger but yielding to a manual depression to activate the plunger through a cam engagement, and a top housing fastened to the base housing to enclose the plunger and button block. The plunger has cam surfaces at a rear end facing forwardly and a beveled lip portion at a front end while the button block has a beveled surface facing the cam surfaces of the plunger. The sash lock further comprises two identical holes formed in the bottom of base housing and a separate keeper for interlocking with the base housing.
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This application claims benefit of provisional application U.S. Ser. No. 60/101,192, filed Sep. 21, 1998.
BACKGROUND OF THE INVENTION
This invention relates to a hydraulic tensioner having tuned piston spring to damp or counteract the motion of the piston at resonant frequencies. More particularly, this invention relates to a hydraulic tensioner in which a large cylindrical mass is interposed between two portions of a piston spring in the inside of the hollow piston of the tensioner.
The piston of a hydraulic tensioner moves inward and outward at the frequency of the engine timing drive. At certain speeds, the piston moves at the resonant frequency of the timing drive. Resonance frequencies cause extreme movements of the piston. The present invention utilizes a solid mass in the center of the spring of the piston to counteract the resonance of the piston. The spring and center member are tuned to resonate at the same resonance frequency of the piston. However, the center member moves in the opposite direction of the piston and thus serves to damp or counteract the extreme movements of the piston when the piston reaches the resonance condition.
The cylindrical center member is inserted between two portions of the spring inside the piston. Thus, the center member serves to reduce the volume of the fluid chamber inside the piston. This reduction in volume decreases the time necessary to purge the air from the piston during engine and tensioner start-up conditions.
A tensioning device, such as a hydraulic tensioner, is used as a control device for a power transmission chain as a chain travels between a plurality of sprockets. As a chain transmits power from a driving sprocket to a driven sprocket, one portion or strand of the chain between the sprockets will be tight while the other portion of the chain will be slack. In order to impart and maintain a certain degree of tension in the slack portion of the chain, a hydraulic tensioner provides a piston that presses against a tensioner arm or other chain guiding mechanism.
Prevention of excess slack in the chain is particularly important in the case of a chain driven camshaft in an internal combustion engine in that a chain without sufficient tension can skip a tooth or otherwise throw off the camshaft timing, possibly causing damage or rendering the engine inoperative. However, in the harsh environment of an internal combustion engine, various factors can cause fluctuations in the chain tension.
For instance, wide variations in temperature and thermal expansion coefficients among the various parts of the engine can cause the chain tension to vary between excessively high or low levels. During prolonged use, wear to the components of the power transmission system can cause a decrease in chain tension. In addition, camshaft and crankshaft induced torsional vibrations cause considerable variations in chain tension. Reverse rotation of an engine, occurring for example in stopping or in failed attempts at starting, can also cause fluctuations in chain tension. For these reasons, a mechanism such as a hydraulic tensioner is desired to ensure the necessary tension on the slack side of the chain.
Hydraulic tensioners are a common method of maintaining proper chain tension. In general, these devices employ a tensioner arm or lever arm that pushes against the chain on the slack side of the chain. This lever arm must push toward the chain, tightening the chain when the chain is slack, and must provide resistive force when the chain tightens.
Typically, a hydraulic tensioner includes a piston in the form of a hollow cylinder. The piston slides within a bore in the housing and is biased outward from the housing in the direction of the tensioner arm and chain by a piston spring. The interior of the piston forms a high pressure fluid chamber with the bore or opening in the housing. The high pressure chamber is connected through a one way check valve to a low pressure chamber or reservoir, which provides or is connected to an exterior source of hydraulic fluid.
Upon start-up, the force of the spring on the piston causes the piston to move further outward as the chain begins to move. Outward movement of the piston creates a low pressure condition in the high pressure fluid chamber, or pressure differential across the inlet check valve. Accordingly, the inlet check valve opens and permits the flow of fluid from the reservoir, or low pressure chamber, into the high pressure chamber. When the high pressure chamber is sufficiently filled with fluid, the force on the chain that moves the piston inward will be balanced by the outward force from the spring and the resistance force of the fluid in the chamber. The force of the chain against the fluid in the chamber also causes the check valve to close, which prevents further addition of fluid to the chamber.
Various types of hydraulic tensioners are described in Suzuki et al., U.S. Pat. No. 5,352,159, Goppett et al., U.S. Pat. No. 4,792,322, and Sosson U.S. Pat. No. 4,850,941. The hydraulic tensioner of Sosson U.S. Pat. No. 4,850,941, has a check valve mounted in the piston, providing a relatively small high pressure chamber. The high pressure chamber is defined by part of the cavity formed in the housing and the piston. The tensioner does not have a spring between the body and the piston or a means for permitting discharge of air from the chamber.
U.S. Pat. No. 4,826,470 discloses a hydraulic tensioner with a check valve mounted in the nose of a piston. The check valve permits air to escape from the piston. U.S. Pat. No. 4,507,103 discloses a hydraulic tensioner with a check valve and vent in series. The check valve has a low opening pressure so that fluid flows from the high pressure chamber through the check valve and then to the tortuous vent path to atmosphere.
SUMMARY OF THE INVENTION
The present invention is directed to a hydraulic tensioner with a solid mass, or center member, in the center of the spring of the piston to counteract the resonance of the piston. The spring and center member are tuned to resonate at the same resonance frequency as the resonance frequency of the piston. However, the center member moves in the opposite direction of the movement of the piston and thus serves to damp or counteract the extreme movements of the piston when the piston reaches the resonance condition.
The cylindrical center member is inserted between two portions of the spring inside the piston. Thus, the center member serves to reduce the volume of the fluid chamber inside the piston. This reduction in volume decreases the time necessary to purge the air from the piston during engine and tensioner start-up conditions.
In one embodiment, the hydraulic tensioner includes a housing with a central bore. A hollow plunger or piston is slidably received within the bore. A source of pressurized fluid, or reservoir, is formed outside of the hollow piston. A one-way check valve is mounted in the base or open end of the piston. A high pressure fluid chamber is formed in the area formed by the hollow piston and the bore. A one-way check valve permits fluid flow from the reservoir into the high pressure chamber of the piston and restricts flow in the reverse direction out of the piston.
Upon outward movement of the piston by the spring, a pressure differential forms across the check valve and fluid flows from the reservoir or other fluid source and through the check valve into the high pressure chamber. The piston moves outward until the inward force on the piston from the chain is balanced by the outward resistance force of the spring and resistance force from the fluid in the high pressure chamber.
For a better understanding of these and other aspects and objects of the invention, references should be made to the following detailed description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of the preferred embodiment of the hydraulic tensioner of the present invention illustrating the cylindrical center member located inside the piston spring.
FIG. 2 is a perspective view of the cylindrical center member of the present invention.
FIG. 3 is a sectional view of one alternate embodiment of the member of the present invention.
FIG. 4 is a perspective view of another alternate embodiment of the cylindrical center member of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to the drawings, the present invention is directed to a hydraulic tensioner with a cylindrical mass or center member located in the center of the piston. The tensioner 10 includes a generally cylindrical, hollow piston 40 that is slidably received in a bore 23 in a housing 20. A one-way check valve 100 is mounted at the bottom of the housing. The check valve forms a high pressure fluid chamber between the check valve and the interior of the piston and bore.
The piston is biased outward from the bore by a piston spring 60. The spring is mounted within the high pressure fluid chamber 80 on the inside of the piston. The piston spring 60 is formed in two parts or portions 62, 64. The cylindrical center member 22 is placed between the two spring parts. The cylindrical center member 22 is preferably solid and of generally cylindrical shape, with a radially extending flange 25 member, which separates the two portions of the spring.
Hydraulic fluid is supplied from an external source of pressurized fluid to the piston through an aperture 70 in the housing 20 and then through the check valve 100. The check valve regulates the flow of hydraulic fluid from a reservoir or other source of pressurized fluid into the high pressure chamber while preventing flow in the reverse direction.
FIG. 1 illustrates one embodiment of the present invention. The hydraulic tensioner 10 includes both a piston spring and a check valve. The tensioner 10 includes a cylindrical housing 20 having a bore 23 in its center to provide an opening for the piston. The housing may be a cartridge housing having threads on the outside of the housing so that it can be received in a threaded bore in the engine block.
A hollow cylindrical piston, or plunger, 40 is slidably mounted concentrically in the bore 23 of the housing. The hollow cylindrical piston 40 has an upper end 41, a lower end 42, and sides 43 and 44. A one-way check valve 100 is mounted in the lower end of the housing. A high pressure fluid chamber 80 is formed between the check valve and the interior of the piston and bore. The size of the high pressure chamber 80 increases as the piston moves outward.
A spring 60 biases the piston in an protruding or outward direction from the bore. A first spring portion or first piston spring 64 is mounted inside the housing and rests on the top of the check valve 100. The other end of the first piston spring rests against the bottom surface of the radially extending flange 25. The first spring preferably wraps about or is concentric with the cylindrical center member 22. Flange 25, also shown in FIG. 4, is located at about the midpoint of the center member 22 and extends in a radial direction.
The second piston spring portion or second piston spring 62 is biased between the upper surface of the radially extending flange 25 and the inner surface of a vent valve with a tortuous path which is fit within the top of the piston 40. The second piston spring 62 contacts the inside of vent valve. The spring biases the piston 40 in a protruding or outward direction from the bore 23. The second spring also preferably wraps about or is concentric with the center member. Alternatively, the first and second spring portions may be portions of a single system in which the cylindrical center member is formed integral with the two spring portions.
The cylindrical center member 22 is preferably solid metal. Alternatively, the center member 22 may be hollow or include internal grooves or recesses for holding the piston springs. The mass of the cylindrical center member is sized in order to provide a damping effect that counters the action of the piston under resonance. Thus, the resonant frequency of the spring 60 and mass 22 combination is calculated using standard resonant condition calculations known in the art. The size and mass of the cylindrical center member is designed and constructed so that the resonant frequency for the spring and mass combination will equal the resonant frequency for the piston. Of course, in practice, the resonant frequencies will not necessarily be equal, but will be on generally the same order to have the necessary effect of the invention. By "on the same order," the present invention contemplates frequencies within 10% of one another. Since the mass travels in a direction opposition that of the piston, the movement of the mass under resonant conditions will damp or limit the movement of the piston under those resonant conditions.
The check valve 100 is preferably mounted in the housing opposite the open end of the piston 40. The one way check valve 100 permits the flow of fluid to the (high pressure) fluid chamber 80 from a (low pressure) reservoir or source of pressurized fluid (not shown) when a pressure differential is created across the valve. The check valve 100 preferably includes a ball 102 and spring 103 biasing the ball 102 toward a ball seat 104 away from a bracket or cage 105. A check valve seal 106 is placed at the base of the valve in the housing. Alternatively, the check valve 100 may also be a variable orifice check valve as shown and described in U.S. Pat. No. 5,259,820 and U.S. Pat. No. 5,277,664, both of which are owned by the assignee of the present application and which are incorporated herein by reference. The exact configuration of the check valve will ultimately depend of the dynamic response desired.
The plastic vent with the tortuous path may be of the type disclosed in Hunter et al. U.S. Pat. No. 5,346,436, or Smith U.S. Pat. No. 5,718,650, both of which are incorporated herein by reference. Other types of vents are also possible. Alternatively, the passage in the top of the piston may be made sufficiently small in diameter in order to serve as a vent.
During start-up of the hydraulic chain tensioner 10 at normal operating conditions, a low pressure condition is created in the high pressure chamber 80, which causes fluid to enter through check valve 100 and begin to fill the high pressure chamber 80. The pressure differential across the check valve 100 opens the valve and allows positive fluid flow into the high pressure chamber 80. Once the inward force of the chain on the piston balances the resistance force of the fluid and spring, the check valve 100 closes, and prevents back flow out of the high pressure chamber 80. During operation, the force of the chain against the piston 40 is balanced by the force of the spring 60 and the pressurized fluid in the high pressure chamber 80.
The presence of the cylindrical center member 22 in the center of the piston and fluid chamber serves to reduce the volume of the chamber. In its preferred embodiment, the center member will have a volume that exceeds 50% of the volume of the fluid chamber. Thus, during tensioner start-up conditions, air in the chamber can be easily purged from the chamber through the vent 52 at the top of the piston.
Another embodiment is shown in FIG. 2, in which the center member 2 includes a pair of radially extending members 24, 26.
Another embodiment is shown in FIG. 3, in which the center member 122 includes a pair of recesses 124, 126 in its center portions. The two piston springs 162, 164 are positioned within the recesses. The remaining structure of the tensioner is the same as the above-described embodiments.
Those skilled in the art to which the invention pertains may make modifications and other embodiments employing the principles of this invention without departing from its spirit or essential characteristics, particularly upon considering the foregoing teachings. The described embodiments are to be considered in all respects only as illustrative and not restrictive and the scope of the invention, is therefore, indicated by the appended claims rather than by the foregoing description. Consequently, while the invention has been described with reference to particular embodiments, modifications of structure, sequence, materials and the like would be apparent to those skilled in the art, yet still fall within the scope of the invention.
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A hydraulic tensioner includes a cylindrical center member or mass to counteract the resonance of the piston. The center member is located between a pair of piston springs inside the fluid chamber. The mass of the center member is selected, along with the spring rates of the piston springs, so that the resonant frequency of the center member matches the resonant frequency of the piston and timing drive. Since the center member moves in the opposite direction from the piston, the center member counteracts or damps the movement of the piston at resonant frequencies.
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STATEMENT REGARDING FEDERAL RIGHTS
[0001] This invention was made with government support under Contract No. DE-AC52-06NA25396 awarded by the U.S. Department of Energy. The government has certain rights in the invention.
BACKGROUND OF INVENTION
[0002] The present application relates generally to atomic, molecular, and nanoparticle deposition techniques. More particularly, the application relates to high-pressure, atomic, molecular, and nanoparticle beam deposition.
[0003] A variety of methods for depositing thin-film coatings have been developed over the last half-century, including chemical vapor deposition, physical vapor deposition (e.g. sputtering, e-beam evaporation, IBAD, etc.), and pulsed laser deposition. Each has its advantages/disadvantages, depending on the material to be deposited, the substrate involved, and the desired material structure.
[0004] Of these coating methods, Pulsed Laser Deposition (PLD) has the advantage that materials can be stochiometrically-deposited, so that the composition of the target and deposit remain nearly identical. However, PLD has the disadvantage of “spall,” i.e. ejecting nano- to micro-scale particulates that travel with the plume to become embedded in the newly-formed deposit. And at high-pressures (i.e. atmospheric pressures and above), homogeneous nucleation tends to occur, where atoms within the plume recombine into nuclei, clusters, and aggregates. In addition, increasing the operating pressure and throughput of a PLD system tends to result in more recombination events. Ultimately, this limits the deposition rate and quality of the deposits that can be created by PLD systems.
[0005] Many different chemical vapor deposition (CVD) techniques exist, including Thermal CVD, plasma enhanced CVD, laser assisted CVD techniques, etc. All of these approaches use chemical precursors that decompose when exposed to elevated temperatures and/or electromagnetic fields—leaving behind a deposit material. The primary disadvantages of CVD methods are: (1) the deposition rate may be very slow, as the process is often maintained at low pressures to reduce homogeneous nucleation, (2) undesired byproducts can be incorporated into the deposit material, (3) obtaining a correct deposit stochiometry is difficult with multi-component systems, (4) the deposit uniformity, composition and crystal structure may depend strongly on the local substrate temperature or other process conditions, and (5) it is difficult (even with plasma enhanced CVD), to ensure that only certain chemical species are present during the reaction, which can influence the ultimate composition/structure of the deposit material. The growth of diamond vs. graphite is an important example, where the species present during the reaction directly influence the resulting crystal structure.
[0006] Accordingly, it would be desirable to provide a method and/or apparatus capable of conducting deposition and etching where specific atomic/molecular species can be directed at a substrate to produce a uniform deposit of desired composition and crystal structure—and at rapid rates. It would also be desirable to provide a method and/or apparatus capable of controlling the stochiometry of the deposit without introducing undesired spall-related particles/agglomerates and/or impurities at high deposition rates.
SUMMARY OF INVENTION
[0007] One embodiment relates to an apparatus for carrying out laser-induced atomic/molecular beam deposition. The apparatus comprises: a chemical precursor delivery system with laser window, a target within the precursor delivery system, a first optic configured to direct a laser beam at the target, a first wall having a aperture, a substrate configured to receive an atomic/molecular beam, a second optic configured to direct a laser beam at either a point proximate to or at the aperture in the first wall, and a third (optional) optic, directing a laser beam at the point where the atomic/molecular beam impinges on the substrate.
[0008] Another embodiment relates to a method for carrying out laser-induced atomic/molecular beam deposition. The method comprises: (1) providing a flow of chemical precursor, (2) providing a target within the flow of chemical precursor, having a desired composition, (3) irradiating the target with a laser beam to provide a plume of target material, (4) directing the plume in a desired direction by use of the flow of chemical precursor, (5) passing the precursor and plume of target material through an aperture into a region of lower pressure, (6) irradiating the plume and precursor to create an atomic/molecular beam, (e.g. to reduce the amount of agglomerated particles in the plume or to partially decompose the precursor), (7) directing the atomic/molecular beam onto a substrate to produce a deposition product, and (8) (optional) irradiating the location where the atomic/molecular beam impinges on the substrate to further decompose the atomic/molecular beam or to produce a specific deposit composition, stochiometry, or crystal structure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a schematic view of an apparatus for carrying out pulsed laser deposition.
DETAILED DESCRIPTION
[0010] Using a focused short-pulse laser beam (i.e., less than about 1 fs to more than about 100 ps), a very high-temperature plasma is created at an aperture through which chemical precursors are flowing. While the chemical precursors are usually gases, they may also be liquids or super-critical fluids). These chemical precursors would typically be Chemical vapor deposition precursors or etchants, e.g. methane, trimethylamine alane, silane, chlorine, etc. Reactive gases, e.g. hydrogen or nitrogen, or inert carrier gases, such as Argon or Krypton may also be used. Adjacent to the aperture, a target comprised of a desired deposition material is placed such that a portion of the short-pulse beam is focused on the target and a plume of target material enters the flow of precursor/reactive/inert gases. Alternatively, nanoparticles of desired deposit material can be created through homogeneous nucleation using a laser beam in a separate chamber (e.g. through photolysis) and carried by the gas flow.
[0011] The plume is oriented such that it will not coat the laser window and/or the precursor delivery system more than necessary. The plume or nanoparticles of desired deposit material are carried along with the flow of precursor and pass through the aperture. A laser beam is focused near or at the aperture, such that some, if not all, molecular bonds are broken on the precursor/reactive gases, and particulates from the plume (or otherwise) are re-heated and potentially evaporated into their atomic components. Some components may be ionized, depending on the temperature.
[0012] During irradiation and while passing through the aperture into a region of relative vacuum, the precursor/plume becomes an atomic/molecular beam, where some of the (thermal) energy is converted into linear motion toward a target substrate or fiber to produce a deposition product. Specific species are produced in the atomic/molecular beam through the properties of the laser beam, the precursor flow rate, the aperture size, the pressure differential across the aperture, the precursors/materials used, etc. The potential for recombination to occur in the atomic/molecular beam is also controlled through similar parameters, so that, if desired, nanoparticles/clusters of specific composition and structure can be grown (or eliminated) in the beam.
[0013] Several apertures may be used to “align” this beam, so that the atomic/molecular beam motion is collimated—and the region were deposition occurs is limited (transverse to the beam). Where atomic/molecular ionized species are present, a magnetic field may be used to select particular species to pass through successive apertures, so that only particular species and/or particles may be present at the final deposition zone. Additional reactive gases may be added in subsequent chambers to form intermediate or desired species within this atomic/molecular beam.
[0014] Next, a bias voltage may be applied between the aperture (where the atomic/molecular beam is created) and the substrate/deposit material. In this way, species can be accelerated toward the substrate/deposit, such that they arrive with a desired energy, and the deposit can act as field-or thermionic-emission sources (e.g. when the deposit is in the form of fibers). Finally, a third laser beam (or a portion of the first/second beams) is directed at the location where the atomic/molecular beam impinges on the substrate/deposit—either to decompose any remaining precursors, desorb undesired by-products off the surface, re-evaporate forming nuclei within the molecular beam, induce the formation of a particular deposit microstructure by controlling the deposit temperature, etc.
[0015] One goal in designing an apparatus is to control the propagation distance of the beam; for example, if it is shorter than the time it takes for components within the beam to recombine into undesireable species/nuclei, such species/nuclei may not be present in the deposition product. More than one atomic beam can also be used to obtain multiple desired species at the reaction zone. One atomic beam can be split into several atomic beams for parallel deposition. Acoustic waves can also be used to separate species, retard or enhance the flow velocity at and beyond the aperture(s), etc. to create desired species or eliminate undesirable species.
[0016] Some benefits include a very high flux of materials along the atomic/molecular beam, so that very high deposition rates are possible. In addition, many disadvantages of the PLD and CVD techniques are eliminated, as species in the beam can be selected, homogeneous nucleation can be controlled, and undesired particulates can be broken into their atomic constituents within the atomic/molecular beam. In addition, optimal precursors and deposition compounds can be created within the atomic/molecular beam, such that particular stochiometries, compositions, and crystal structures can be created and undesired impurities and particulates are eliminated within the deposit material.
[0017] Consider, for example, the deposition of diamond-like carbon at high rates, using hydrogen as a carrier gas and methane or adamantane (for example) as precursor gases. The laser-heated plasma at the aperture will crack the hydrocarbon(s), and given the correct conditions, leave some sp 3 bonded constituents in the gas flow. Using species selectivity, optimal species for diamond growth can be selected through the apertures—and accelerated toward the substrate/deposit. The hydrogen may also be decomposed into atomic hydrogen and selected through the apertures, enhancing the rate of graphite etching. This should allow diamond-like carbon and single-crystal diamond to be grown at large rates.
[0018] Referring to FIG. 1 , apparatus 10 includes a target 12 that is irradiated with a pulsed laser beam 14 . A plume of material 16 is ejected from the target which is configured such that plume 16 travels in the direction of wall 18 . A carrier or precursor gas may be used to direct the flow of plume 16 . Wall 18 includes an aperture 20 through which at least a portion of plume 16 may pass through. A second laser beam 22 is directed toward the aperture 20 to at least partially irradiate plume 16 . While second laser beam 22 is directed at a point up stream of aperture 20 , it may be desirable to direct another beam at a point on the downstream side of aperture 20 . Alternatively, only a beam directed at a point on the downstream side of aperture 20 may be used. The region downstream of aperture 20 may be at a pressure lower than the region upstream of aperture 20 to accelerate the atomic beam. The carrier or precursor gas may be introduced through an aperture and directed in the direction of wall 18 and aperture 20 .
[0019] The second laser beam 22 energizes the contents of plume 16 to break down agglomerates and nuclei resulting in an atomic or molecular beam. The beam passes between wall 18 and wall 24 . In the region between walls 18 and 24 , a reactive gas may be introduced into the atomic beam to change the composition of the beam. Again, wall 24 includes an aperture 26 and a third laser beam 28 may be directed toward the aperture 26 to at least partially irradiate the atomic beam. While third laser beam 28 is directed at a point up stream of aperture 26 , it may be desirable to direct another beam at a point on the downstream side of aperture 26 . Alternatively, only a beam directed at a point on the downstream side of aperture 26 may be used. The region downstream of aperture 26 may be at a pressure lower than the region upstream of aperture 26 to accelerate the atomic beam. In some embodiments, an electrical potential may be provided between wall 18 and wall 24 to accelerate or slow charged species. Also, a magnetic field may be used to divert charged species of a certain mass and velocity away from aperture 26 , thus selecting what species will advance towards the substrate 36 .
[0020] Another optional chamber is shown between walls 24 and 30 . The atomic beam passes between wall 24 and wall 30 . In the region between walls 24 and 30 , a reactive gas may be introduced into the atomic beam to change the composition of the beam. Again, wall 30 includes an aperture 32 and a fourth laser beam 34 may be directed toward the aperture 32 to at least partially irradiate the atomic beam. While fourth laser beam 28 is directed at a point up stream of aperture 32 , it may be desirable to direct another beam at a point on the downstream side of aperture 32 . Alternatively, only a beam directed at a point on the downstream side of aperture 32 may be used. The region downstream of aperture 32 may be at a pressure lower than the region upstream of aperture 32 to accelerate the atomic beam. In some embodiments, an electrical potential may be provided between wall 24 and wall 30 to accelerate or slow charged species. Also, a magnetic field may be used to divert charged species of a certain mass and velocity away from aperture 32 , thus selecting what species will advance towards the substrate 36 .
[0021] The beam may exit the chamber between walls 24 and 30 through aperture 32 . The atomic beam is then directed toward substrate 36 where fibers, thin films, and other useful structures may be grown. A fifth laser beam 38 (or portion of another beam) is directed at the substrate/fibers at the point of deposition. The fifth laser beam 38 may be used to decompose any remaining precursors, desorb undesired by-products off the surface, re-evaporate forming nuclei within the molecular beam, and/or to induce the formation of a particular deposit microstructure by controlling the deposit temperature.
[0022] While the apparatus is shown having three walls, other numbers may be used. A single wall may be used in conjunction with a laser beam such as beam 38 directed to a point near the point of deposition. Alternatively, a greater number of walls may be used to provided additional chambers for the introduction of reactive gasses.
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A method for carrying out pulsed laser deposition is disclosed. The method comprises providing a target having a desired composition; irradiating the target with a pulsed laser beam to provide a plume of target material; and directing the plume in a desired direction by use of an inert carrier gas. The plume of target material is passed through an aperture to create an atomic beam. One or both of the plume or the atomic beam is irradiated to reduce the amount of agglomerated particles in the atomic beam. The atomic beam is directed onto a substrate to produce a deposition product. An apparatus for carrying out the method is also disclosed.
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FIELD OF THE INVENTION
[0001] This invention relates to the fields of molecular biology, medicine diagnostics. This invention particularly relates to methods for preparing and using fixed-treated cell lines and tissue in fluorescence in situ hybridization.
BACKGROUND OF THE INVENTION
[0002] Advancements in the understanding of gene expression and epidemiology combined with developments in technology have allowed for the correlation of genetic expression with, for example, disease states. An accurate correlation may enable risk assessment for an individual based on the expression profile of their individual cells. Further, drug screening and other research based protocols may quickly generate data in cell lines or tissue samples that can be extended to develop treatments for human disease. However, most of the methodologies available for evaluation of cell lines or tissue have well-known drawbacks. For example, methods that require disaggregation of the sample, such as Southern, Northern, or Western blot analysis, are rendered less accurate by dilution of the malignant cells by the normal or otherwise non-malignant cells that are present in the same sample. Furthermore, the resulting loss of tissue architecture precludes the ability to correlate, for example, malignant cells with the presence of genetic abnormalities in a context that allows morphological specificity. This issue is particularly problematic in tissue types known to be heterogeneous, such as in human breast carcinoma, where a significant percentage of the cells present in any area may be non-malignant.
[0003] Another drawback is that many of the art recognized techniques require the tissue being analyzed to be fresh. Typically, however, it is not always possible in the clinical setting to work on cell lines or tissue as soon as they are available. Accordingly, cell lines or tissue are often preserved in paraffin. Processes for treating a paraffin-embedded tissue sample for gene analysis have been described, for example, U.S. Pat. Nos. 5,672,696 and 6,248,535. Typically treatments comprise treating tissue cells freed of paraffin with a solution containing a surfactant, a protease, etc. at room temperature to upwards of 60° C. for 4 to 48 hours to disrupt the tissue cells, removing impurities (i.e., substances other than nucleic acid) by a two-phase separation method (i.e., a method comprising separation into an aqueous phase containing the nucleic acid and an organic solvent phase containing denatured protein and the like by addition of one or more organic solvents such as phenol, chloroform, etc.), and then adding an alcohol to the residue to precipitate the nucleic acid in the aqueous phase (Jikken Igaku, Vol. 8, No. 9, pp. 84-88, 1990, YODOSHA CO., LTD.). While this technique allows for the analysis of gene expression, the purification disrupts cellular architecture and does not allow the application of in situ hybridization techniques.
[0004] As described in U.S. Pat. Nos. 5,750,340 or 6,165,723, in situ hybridization (ISH) is a powerful and versatile tool for the detection and localization of nucleic acids (DNA and RNA) within cell or tissue preparations. By the use of labeled DNA or RNA probes, the technique provides a high degree of spatial information in locating specific DNA or RNA target within individual cells or chromosomes. ISH is widely used for research and potentially for diagnosis in the areas of prenatal genetic disorders, and molecular cytogenetics. In the general area of molecular biology, ISH is used to detect gene expression, to map genes, to identify sites of gene expression, to localize target genes, and to identify and localize various viral and microbial infections. Currently, the application of the ISH technology research is being expanded into tumor diagnosis, preimplantation genetic diagnosis for in vitro fertilization, evaluation of bone marrow transplantation, and analysis of chromosome aneuploidy in interphase and metaphase nuclei.
[0005] In ISH, labeled nucleic acids (DNA or RNA) are hybridized to chromosomes, DNA or mRNAs in cells which are immobilized on microscope glass slides (In Situ Hybridization: Medical Applications (eds. G. R. Coulton and J. de Belleroche), Kluwer Academic Publishers, Boston (1992); In Situ Hybridization: In Neurobiology; Advances in Methodology (eds. J. H. Eberwine, K. L. Valentino, and J. D. Barchas), Oxford University Press Inc., England (1994); In Situ Hybridization: A Practical Approach (ed. D. G. Wilkinson), Oxford University Press Inc., England (1992)). Numerous non-isotopic systems have been developed to visualize labeled DNA probes including, for example, a) fluorescence-based direct detection methods, b) the use of digoxigenin- and biotin-labeled DNA probes coupled with fluorescence detection methods, and c) the use of digoxigenin- and biotin-labeled DNA probes coupled with antibody-enzyme detection methods. When fluorescence-labeled nucleic acid (DNA or RNA) probes are hybridized to cellular DNA or RNA targets, the hybridized probes can be viewed directly using a fluorescence microscope. By using multiple nucleic acid probes with different fluorescence colors, simultaneous multicolored analysis (i.e., for multiple genes or RNAs) can be performed in a single step on a single target cell (Levsky et al. Science 2001). Fluorochrome-directly labeled nucleic acid probes eliminate the need for multi-layer detection procedures (e.g., antibody-based system), which allows for fast processing and also reduces non-specific background signals. Therefore, fluorescence in situ hybridization (FISH) has become an increasingly popular and valuable tool in both basic and clinical sciences.
[0006] Unfortunately, although FISH is an extremely useful technique, detection of mRNA, especially pre-mRNA, in paraffin-embedded or otherwise fixed-treated cell lines or tissue (i.e., “fixed-treated tissue” defined as tissue that is not fresh frozen) is currently difficult, if not impossible. FISH is a highly sensitive assay that allows the detection of nucleic acid within undisturbed cellular and tissue architecture and the use of synthetic oligomer probes in FISH has improved the sensitivity of the process; however, to date FISH has only been successfully conducted in cells grown through cell-line culture. mRNA detection through FISH has not been successfully conducted in tissue until just recently (Nguyen et al., J Biol Chem, November 1;277(44):41960-9 (2002)); Paris et al., Science, July 13;293 (5528):293-7 (2001)).
[0007] Detection is difficult for a number of reasons, including interference caused by the creation of chemical bonds during fixation processes as well as native autofluorescence in the cell lines or tissue. The ability to easily apply FISH to such cell lines or tissue would be of great interest because of the large amount of clinically relevant cell lines and tissue that have been (and continue to be) preserved in this fashion.
[0008] U.S. Pat. No. 5,856,089 describes in situ hybridization methods using nucleic acid probes for single copy sequences for detecting chromosomal structural abnormalities in fixed tissue obtained from a patient suspected of having a chromosomal structural abnormality. The methods include the use of bisulfite ion on the fixed cells.
[0009] U.S. Pat. No. 5,672,696 describes preparation of a sample for a gene analysis or high-purity nucleic acid suitable for gene amplification from a paraffin-embedded tissue sample comprising heating an aqueous suspension containing a surfactant having a protein-denaturation action and a deparaffinized tissue sample obtained from a paraffin-embedded tissue sample at 60° C. or higher. However, it is not an object of this patent to preserve the cellular architecture.
[0010] FISH has historically been combined with classical staining methodologies in an attempt to correlate genetic abnormalities with cellular morphology [see e.g., Anastasi et al., Blood 77:2456-2462 (1991); Anastasi et al., Blood 79:1796-1801 (1992); Anastasi et al., Blood 81:1580-1585 (1993); van Lom et al., Blood 82:884-888 (1992); Wolman et al., Diagnostic Molecular Pathology 1(3): 192-199 (1992); Zitzelberger, Journal of Pathology 172:325-335 (1994)]. However, several of these studies address hematological disorders where genetic changes are assessed in freshly fixed smears from bone marrow aspirates or peripheral blood specimens. U.S. Pat. No. 6,573,043 describes combining morphological staining and/or immunohistochemistry (IHC) with fluorescence in situ hybridization (FISH) within the same section of a tissue sample.
[0011] U.S. Pat. No. 6,534,266 describes an in situ hybridization method for detecting and specifically identifying transcription of a multiplicity of different target sequences in a cell. The method includes assigning a different bar code to at least five target sequences, with each target sequence containing at least one predetermined subsequence. Each bar code contains at least one fluorochrome, and at least one bar code comprises at least two different, spectrally distinguishable fluorochromes. A probe set specific for each target sequence is provided in the method. Each probe set contains a hybridization probe complementary to each subsequence in the target sequence. Each probe is labeled with a fluorochrome, and the fluorochromes in each probe set collectively correspond to the bar code for the target sequence of that probe set. Similar techniques are envisioned in combination with the invention disclosed herein.
[0012] Further, although spotted chip expression microarrays have been used extensively to detect the presence or absence of multiple specific mRNAs simultaneously in tissue, to date the effective application of this technique has been limited to fresh frozen tissue and does not describe an easy application utilizing paraffin-embedded or other fixed-treated tissue (for example, see United States Patent Publication Nos. 20030040035 and 20020192702). Because much of the cell lines and tissue available for scientific or medical study has been fixed, the ability to effectively use spotted chip arrays on fixed-treated cell lines and tissue would be of great potential value in (1) the discovery of the molecular mechanisms of the cell and its surrounding tissue in health and disease, (2) the creation of tests diagnostic of disease, (3) the creation of treatments therapeutic for disease, and (4) the identification of agents that are toxic to cells. Therefore, the present invention fulfills a need in the art by providing, for example, a process termed “mRNA liberation in fixed treated tissue or ‘MLIFFT’” to enable the detection of mRNA, especially pre-mRNA, in fixed treated tissue.
SUMMARY OF THE INVENTION
[0013] As will be understood by one of skill in the art, in one aspect the present invention provides a method for rendering fixed treated cell-lines and tissue (i.e. paraffin embedded tissue) susceptible to further analysis using fluorescence detection methods. Such methods were formally not compatible with fixed treated cell lines or tissue. This invention, therefore, provides a method and composition which will be useful in a range of protocols as will be apparent to one of skill in the art. While several of these protocols will be herein described, such description is not meant in any way to limit the applicability of the current invention. In one aspect, the invention provides a method of reducing autofluorescence in a sample during FISH. The process comprises treating the cell-lines or tissue with ammonia-ethanol and sodium borohydride and pressure cooking prior to performing FISH.
[0014] In one aspect, the invention provides a method, termed MLIFTT, to enable the detection of mRNA, especially pre-mRNA, in fixed-treated cell lines or tissue. The invention also describes the linkage of the MLIFTT process to enable the detection of one or more specific mRNAs in fixed-treated cell lines or tissue through the process of fluorescence in situ hybridization (“Tissue-FISH”) with or without quantitative computational fluorescence microscopic analysis. Such linkage allows the use of fixed treated cells in the evaluation of toxicological or therapeutic responses to agents which were administered to the cells prior fixation. The invention also describes the linkage of the MLIFTT process to microarray analyses using fixed-treated cell lines or tissue. The invention also describes the linkage of the MLIFTT process to enable other potential measurements.
[0015] In one aspect, the invention provides a process to treat cell lines or tissue for the specific purpose of detecting mRNA, especially pre-mRNA. The process comprises treating the cell lines or tissue with ammonia-ethanol and sodium borohydride and pressure cooking the cell lines or tissue to achieve improved detection of mRNA. Without being bound by theory, it is thought that the chemical treatments reduce the auto-fluorescence of the cell lines or tissue and the physical treatments overcome interference created by the fixative-induced chemical bonds.
[0016] In another aspect, the invention combines a method to pre-treat the cell lines or tissue with advances in computational fluorescence microscopy with specialized probes designed to visualize expression of one or many genes simultaneously inside single cells (either alone or within a tissue). Single-cell expression profiling is valuable because it enables the simultaneous detection of the presence (or absence) of multiple molecular entities or “markers” within the cell. The presence (or absence) of these molecular entities characterizes and provides insight into the regulatory activity of each cell. The detection of these entities has potential value in (1) the discovery of the molecular mechanisms of the cell and its surrounding tissue in health and disease, (2) the creation of tests that are diagnostic of disease, (3) the identification of agents that are therapeutic for disease, and (4) the identification of agents that are toxic to cells.
[0017] In another aspect, the invention provides a process combining the pre-treatment of the cell lines or tissue by chemical and physical processes followed by the detection of specific pre-mRNA transcript(s) through specific fluorochrome-labeled oligo-probes (“Tissue-FISH”). The pre-treatment process is the treatment of the cell lines or tissue with ammonia-ethanol and sodium borohydride and pressure cooking the cell lines or tissue. Following the treatment, specific probes are applied to the cell lines or tissue to detect specific pre-mRNA transcripts. The specific probes have fluorochromes which can be detected through quantitative computational fluorescence microscope analysis. In this way, an individual could simultaneously detect multiple specific pre-mRNA entities in a single cell. The limit of the number of specific pre-mRNA entities is limited only by the number of unique available fluorochromes that can be attached to these probes.
[0018] In another aspect, the invention provides a pre-mRNA labeling technique that can increase the number of molecular entities that may be simultaneously detected beyond the number of uniquely (or spectrally distinct) available fluorochromes. This feature of the invention is to create and apply multiple oligo-probes to the cell lines or tissue which are specific for a pre-mRNA transcript that, when attached to their target pre-mRNA, create a unique fluorescent barcode for each transcript. These barcodes can then be detected using quantitative computational fluorescence microscopic analysis. The number of potential pre-mRNA transcripts that can be simultaneously detected has been increased from the number of available unique fluorochromes (“n”) to n raised to the power of the number of fluorochrome-unique probes that can be created for a specific pre-mRNA.
[0019] In another aspect, the invention provides a method to quantify the level of specific pre-mRNA expression by using a computerized detection system to quantify the level of attached fluorochrome labeling by measuring the intensity of the fluorochrome signal. The level of specific pre-mRNA expression is calculated by assuming it is proportional to the level of intensity of the fluorochrome signal.
[0020] In another aspect, the invention includes a process of combining the pre-treatment of the fixed-treated cell lines or tissue by chemical and physical processes followed by the detection of specific mRNA transcript(s) through spotted chip arrays. The pre-treatment process is the treatment of the cell lines or tissue with ammonia-ethanol and sodium borohydride and pressure cooking the cell lines or tissue. Following this pre-treatment of the fixed-treated cell lines or tissue, the cell lines or tissue is disrupted and then applied to spotted chip arrays to detect the presence and level (or absence) of specific mRNAs.
[0021] In yet another aspect, the invention provides a process of measuring the presence or absence or quantified amount of specific pre-mRNA and/or mRNA using probes to detect these entities in (i) cell lines or (ii) cell lines or tissue from animals or (iii) cell lines or tissue from humans, to determine if the respective cell lines or tissue, when treated with a test compound, displays a gene expression profile indicating a potential therapeutic or toxic activity for the test compound. Such effects would be revealed by differences in pre-mRNA or mRNA expression between the treated and untreated cell lines or tissue. Probes can be designed, for example, to specifically target known therapeutic or toxicologic pathways. This process could be conducted on culture cell lines or fresh frozen cell lines or tissue or fixed cells or fixed tissue. If this process is conducted on fixed cells or fixed tissue, the MLIFTT process could be employed to liberate the pre-mRNA or mRNA for measurement. FISH applied to cell lines or Tissue-FISH applied to cell lines could be used to enable the measurement of the pre-mRNA or mRNA. To make the measurement more effective and valuable, multiplexed FISH applied to cell lines or Tissue-FISH could be used to measure multiple pre-mRNAs or mRNAs simultaneously in the same sample of cell lines or tissue. This would be more valuable because it 1) more efficiently uses potentially scarce cell lines and tissue as well as expensive reagents, 2) saves time, and 3) allows investigators to see the simultaneous interrelationships of gene expression more clearly in single cells or groups of cells.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 : Detection of SMG-1 gene on Paraffin-embedded prostate Carcinoma using Cy3 and Cy5 labeled probe (arrows are pointing at two transcription sites).
DETAILED DESCRIPTION OF THE INVENTION
[0023] Before the present methods, kits and uses therefore are described, it is to be understood that this invention is not limited to the particular methodology, protocols, cell lines, animal species or genera, constructs, and reagents described which may be modified or substituted as would be known to one of skill in the art. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention which will be limited only by the appended claims.
[0024] It must be noted that as used herein and in the appended claims, the singular forms “a”, “and”, and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a genetic alteration” includes a plurality of such alterations and reference to “a probe” includes reference to one or more probes and equivalents thereof known to those skilled in the art, and so forth.
[0025] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this invention belongs. Although any methods, devices and materials similar or equivalent to those described herein can be used in the practice or testing of the invention, the preferred methods, devices and materials are now described.
[0026] All patents and publications mentioned herein are incorporated herein by reference in their entirety.
[0027] Publications cited herein are cited for their disclosure prior to the filing date of the present application. Nothing here is to be construed as an admission that the inventors are not entitled to antedate the publications by virtue of an earlier priority date or prior date of invention. Further the actual publication dates may be different from those shown and require independent verification.
[0028] As will be understood by one of skill in the art, in one aspect the present invention provides a method for rendering fixed treated cell-lines and tissue (i.e. paraffin embedded tissue) susceptible to further analysis using fluorescence detection methods. Such methods were formally not compatible with fixed treated cell lines or tissue. This invention, therefore, provides a method and composition which will be useful in a range of protocols as will be apparent to one of skill in the art. While several of these protocols will be herein described, such description is not meant in any way to limit the applicability of the current invention.
[0029] The present invention is directed, in part, towards improved methods for directly detecting the presence of a target nucleic acid in cells of paraffin-embedded or otherwise fixed-treated cell lines or tissue, a process termed “mRNA liberation in fixed-treated tissue or ‘MLIFTT’”. More specifically, novel improvements of the traditional fixative/pretreatment methods are described which employ treatment of the tissue with ammonia-ethanol and sodium borohydride and pressure cooking the tissue to achieve improved detection of pre-mRNA.
[0030] As used herein, “Tissue-FISH” refers to the use of fluorescent labeled probes, for example, of up to approximately 50 bp in the detection of nucleic acids in paraffin embedded tissue samples.
[0031] One of skill in the art will understand that, with respect to the instant invention, references to tissue are generally equally applicable to cell lines. Accordingly, although one term may be used with respect to a particular method, it should be understood that the composition or method applies equally to the other. In referring generally to the types of material that may be utilized according to the invention, the inventors may use terms like “sample” etc.
[0032] As used herein, “fluorochrome” refers to a particular fluorescent dye, e.g., Cy3, Cy5, without regard to number of individual dye molecules, and without regard to chemical conjugation.
[0033] As used herein, “fluorophore” refers to an individual fluorescent dye molecule or conjugated moiety.
[0034] As used herein, the term “nucleic acid” refers to DNA, RNA, or the equivalent thereof, including pre-mRNA, cDNA, chromosomal, mitochondrial, viral and/or bacterial nucleic acids. The term “nucleic acid” encompasses either or both strands of a double stranded nucleic acid molecule and includes any fragment or portion of an intact nucleic acid molecule.
[0035] As used herein, the term “probe” refers to synthetic or biologically produced nucleic acids that are engineered to contain specific nucleotide sequences which hybridize under stringent conditions to target nucleic acid sequences.
[0036] As used herein, a “labeled probe” is defined as a probe which is prepared with a marker moiety for detection. The marker moiety is attached at either the 5′ end, the 3′ end, internally, or in any possible combination thereof. The preferred moiety is an identifying label such as a fluorophore. The labeled probe may also be comprised of a plurality of different nucleic acid sequences each labeled with a marker moiety. It may be beneficial to label the different nucleic acid sequences each with a different marker moiety.
[0037] By “subject” or “patient” is meant any single subject for which therapy is desired, including humans, cattle, dogs, guinea pigs, rabbits, chickens, insects and so on. Also intended to be included as a subject are any subjects involved in clinical research trials not showing any clinical sign of disease, or subjects involved in epidemiological studies, or subjects used as controls.
[0038] “Toxicology analysis” as used herein refers to protocols directed towards identifying, for example, genetic expression (or lack thereof) indicative of a toxic response by the cell to, for example, an agent. Toxicological response pathways are familiar to those of skill in the art.
[0039] By “tissue sample” is meant a collection of similar cells obtained from a tissue of a subject or patient, preferably containing nucleated cells with chromosomal material. The four main human tissues are (1) epithelium; (2) the connective tissues, including blood vessels, bone and cartilage; (3) muscle tissue; and (4) nerve tissue. The source of the tissue sample may be solid tissue as from a fresh, frozen and/or preserved organ or tissue sample or biopsy or aspirate; blood or any blood constituents; bodily fluids such as cerebral spinal fluid, amniotic fluid, peritoneal fluid, or interstitial fluid; cells from any time in gestation or development of the subject. The tissue sample may also be primary or cultured cells or cell lines. The tissue sample may contain compounds which are not naturally intermixed with the tissue in nature such as preservatives, anticoagulants, buffers, fixatives, nutrients, antibiotics, or the like. In one embodiment of the invention, the tissue sample is “non-hematological tissue” (i.e. not blood or bone marrow tissue).
[0040] For the purposes herein a “section” of a tissue sample is meant a single part or piece of a tissue sample, e.g. a thin slice of tissue or cells cut from a tissue sample. It is understood that multiple sections of tissue samples may be taken and subjected to analysis according to the present invention, provided that it is understood that the present invention comprises a method whereby the same section of tissue sample is analyzed at both morphological and molecular levels, or is analyzed with respect to both protein and nucleic acid.
[0041] As used herein, “cell line” refers to a permanently established cell culture that will proliferate given appropriate fresh medium and space.
[0042] By “correlate” or “correlating” is meant comparing, in any way, the performance and/or results of a first analysis with the performance and/or results of a second or further analysis. For example, one may use the results of a first analysis in carrying out the second analysis and/or one may use the results of a first analysis to determine whether a second analysis should be performed and/or one may compare the results of a first analysis with the results of a second analysis. With respect to the embodiment of morphological analysis followed by FISH, one may use the results obtained upon morphological staining to determine area(s) of a tissue section which are normal and/or area(s) which are cancerous. Thus, histological normal area(s) in a heterogeneous tumor biopsy may be used as internal normal control(s).
[0043] By “gene” is meant any nucleic acid sequence or portion thereof with a functional role in encoding or transcribing a protein or regulating other gene expression. The gene may consist of all the nucleic acids responsible for encoding a functional protein or only a portion of the nucleic acids responsible for encoding or expressing a protein. The nucleic acid sequence may contain a genetic abnormality within exons, introns, initiation or termination regions, promoter sequences, other regulatory sequences or unique adjacent regions to the gene.
[0044] By “genetic abnormality” is meant a deletion, substitution, addition, translocation, amplification and the like relative to the normal native nucleic acid content of a cell of a subject.
[0045] By “disease gene” is meant a gene that results in altered protein product (i.e., protein different from native protein in terms of sequence, structure and/or amount expressed) and results in a disease.
[0046] By “deletion” is meant the absence of all or part of a gene.
[0047] By “amplification” is meant the presence of one or more extra gene copies in a chromosome complement.
[0048] The word “label” when used herein refers to a compound or composition which is conjugated or fused directly or indirectly to a reagent such as a nucleic acid probe or an antibody and facilitates detection of the reagent to which it is conjugated or fused. The label may itself be detectable (e.g., radioisotope labels or fluorescent labels) or, in the case of an enzymatic label, may catalyze chemical alteration of a substrate compound or composition which is detectable.
[0049] The term “fluorescent labeled nucleic acid probe” refers to a probe comprising (1) a nucleic acid sequence tagged with a fluorescent dye (2) capable of hybridizing with a target nucleic acid sequence.
[0050] By “morphological stain” is meant a dye that stains different cellular components, in order to facilitate identification of cell type and/or disease state by light microscopy. Preferably, the morphological stain is readily distinguishable from any label used in the FISH analysis, e.g., a stain which will not autofluoresce at the same wavelength as the fluorochrome used in the FISH analysis.
[0051] The term “antibody” is used in the broadest sense and specifically covers monoclonal antibodies, polyclonal antibodies, multispecific antibodies (e.g., bispecific antibodies), and antibody fragments so long as they bind specifically to a target antigen.
[0052] The term “monoclonal antibody” as used herein refers to an antibody obtained from a population of substantially homogeneous antibodies, i.e., the individual antibodies comprising the population are identical except for possible naturally occurring mutations that may be present in minor amounts. Monoclonal antibodies are highly specific, being directed against a single antigenic site. Furthermore, in contrast to conventional (polyclonal) antibody preparations that typically include different antibodies directed against different determinants (epitopes), each monoclonal antibody is directed against a single determinant on the antigen. The modifier “monoclonal” indicates the character of the antibody as being obtained from a substantially homogeneous population of antibodies, and is not to be construed as requiring production of the antibody by any particular method. The “monoclonal antibodies” may also be isolated from phage antibody libraries using the techniques described in Clackson et al., Nature 352:624-628 (1991) and Marks et al., J. Mol. Biol. 222:581-597 (1991), for example.
[0053] The monoclonal antibodies herein specifically include “chimeric” antibodies (immunoglobulins) in which a portion of the heavy and/or light chain is identical with or homologous to corresponding sequences in antibodies derived from a particular species or belonging to a particular antibody class or subclass, while the remainder of the chain(s) is identical with or homologous to corresponding sequences in antibodies derived from another species or belonging to another antibody class or subclass, as well as fragments of such antibodies, so long as they exhibit the desired biological activity [U.S. Pat. No. 4,816,567; and Morrison et al., Proc. Natl. Acad. Sci. USA 81:6851-6855 (1984)].
[0054] The term “primary antibody” herein refers to an antibody which binds specifically to the target protein antigen in a tissue sample. A primary antibody is generally the first antibody used in an immunohistochemical procedure. In one embodiment, the primary antibody is the only antibody used in an IHC procedure.
[0055] The term “secondary antibody” herein refers to an antibody which binds specifically to a primary antibody, thereby forming a bridge between the primary antibody and a subsequent reagent, if any. The secondary antibody is generally the second antibody used in an immunohistochemical procedure. The novel and unique fluorescence in situ hybridization and detection technique described herein is a method which allows the use of recombinant DNA or RNA probes with paraffin-embedded or otherwise fixed-treated samples, including for example, cells, microorganisms, or tissue sections, and is compatible with microscopic examination routinely performed in bacteriology, parasitology, histology or pathology laboratories. The present invention applies a nucleic acid probe of predetermined nucleotide sequence to the sample cells or tissue and to the examination of the sample by microscopy, for example, to determine which cells or tissues within the population contain the specific nucleic acid target sequences of interest.
[0000] Sample Preparation of Fixed Treated Tissue
[0056] Any tissue sample from a subject may be used. Examples of tissue samples that may be used include, but are not limited to, breast, prostate, ovary, colon, lung, endometrium, stomach, salivary gland or pancreas. The tissue sample can be obtained by a variety of procedures including, but not limited to surgical excision, aspiration or biopsy. The tissue may be fresh or frozen. In one embodiment, the tissue sample is fixed and embedded in paraffin or the like.
[0057] The tissue sample may be fixed (i.e. preserved) by conventional methodology [See e.g., “Manual of Histological Staining Method of the Armed Forces Institute of Pathology,” 3rd edition (1960) Lee G. Luna, HT (ASCP) Editor, The Blakston Division McGraw-Hill Book Company, New York; The Armed Forces Institute of Pathology Advanced Laboratory Methods in Histology and Pathology (1994) Ulreka V. Mikel, Editor, Armed Forces Institute of Pathology, American Registry of Pathology, Washington, D.C.]. One of skill in the art will appreciate that the choice of a fixative is determined by the purpose for which the tissue is to be histologically stained or otherwise analyzed. One of skill in the art will also appreciate that the length of fixation depends upon the size of the tissue sample and the fixative used. By way of example, neutral buffered formalin, Bouin's or paraformaldehyde, may be used to fix a tissue sample.
[0058] Generally, the tissue sample is first fixed and is then dehydrated through an ascending series of alcohols, infiltrated and embedded with paraffin or other sectioning media so that the tissue sample may be sectioned. Alternatively, one may section the tissue and fix the sections obtained. By way of example, the tissue sample may be embedded and processed in paraffin by conventional methodology (See e.g., “Manual of Histological Staining Method of the Armed Forces Institute of Pathology”, supra). Examples of paraffin that may be used include, but are not limited to, Paraplast, Broloid, and Tissuemay. Once the tissue sample is embedded, the sample may be sectioned by a microtome or the like (See e.g., “Manual of Histological Staining Method of the Armed Forces Institute of Pathology”, supra). By way of example for this procedure, sections may range from about three microns to about five microns in thickness. Once sectioned, the sections may be attached to slides by several standard methods. Examples of slide adhesives include, but are not limited to, silane, gelatin, poly-L-lysine and the like. By way of example, the paraffin embedded sections may be attached to positively charged slides and/or slides coated with poly-L-lysine.
[0059] If so desired, the tissue sections may be deparaffinized by several conventional standard methodologies. For example, xylenes and a gradually descending series of alcohols may be used (See e.g., “Manual of Histological Staining Method of the Armed Forces Institute of Pathology”, supra). Alternatively, commercially available deparaffinizing non-organic agents such as Hemo-De® (CMS, Houston, Tex.) may be used.
[0060] Preparing Cell-lines and Tissue for Fluorescence In Situ Hybridization
[0061] The present invention is directed towards a method for preparing a sample for fluorescence in situ hybridization, comprising the steps of:
(a) pressure cooking the sample; and (b) treating the pressure cooked sample with ammonia-ethanol and sodium borohydride.
[0064] Preferably, the pressure cooking is performed in a decloaking chamber at a temperature of about 125° C. reaching a pressure of between about 20 to about 24 PSI. Preferably, the ammonia-ethanol is used in a concentration of about 0.25%. Preferably, the sodium borohydrate is used in a concentration of about 5%.
[0065] As will be apparent to one of skill in the art, this method is ideally suited to fixed-treated cell lines and tissue, particularly paraffin embedded tissue. In a preferred embodiment, the tissue is mammalian. In another preferred embodiment, the mammalian tissue is human.
[0066] Accordingly, the present invention is directed towards a pressure cooked composition comprising:
(a) a fixed-treated tissue; (b) ammonia-ethanol; and (c) sodium borohydride.
[0070] In a preferred embodiment, the ammonia-ethanol concentration is about 0.25% in the pressure cooked composition. In another preferred embodiment, the sodium borohydride concentration is about 5% in the pressure cooked composition.
[0071] In one aspect of the invention, the pressure cooked composition can be used in FISH. Accordingly, in one aspect FISH further comprises a quantification step wherein an mRNA expression level is calculated as a proportion of fluorochrome signal intensity of the mRNA.
[0072] In one aspect of the invention, the pressure cooked and treated composition will display reduced autofluorescence as compared to compositions which are not so treated. In one aspect, the composition will display 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70% or more of a reduction in autofluorescence.
[0073] Fluorescence In Situ Hybridization (FISH)
[0074] In situ hybridization may be performed by several conventional methodologies [See for e.g. Leitch et al. In Situ Hybridization: a practical guide, Oxford BIOS Scientific Publishers, Micropscopy handbooks v. 27 (1994)]. In one in situ procedure, fluorescent dyes (such as fluorescein isothiocyanate (FITC) which fluoresces green when excited by an Argon ion laser) are used to label a nucleic acid sequence probe which is complementary to a target nucleotide sequence in the cell. Each cell containing the target nucleotide sequence will bind the labeled probe producing a fluorescent signal upon exposure of the cells to a light source of a wavelength appropriate for excitation of the specific fluorochrome used.
[0075] Various degrees of hybridization stringency can be employed. As the hybridization conditions become more stringent, a greater degree of complementarity is required between the probe and target to form and maintain a stable duplex. Stringency is increased by raising temperature, lowering salt concentration, or raising formamide concentration. Adding dextran sulfate or raising its concentration may also increase the effective concentration of labeled probe to increase the rate of hybridization and ultimate signal intensity. After hybridization, slides are washed in a solution generally containing reagents similar to those found in the hybridization solution with washing time varying from minutes to hours depending on required stringency. Longer or more stringent washes typically lower nonspecific background but run the risk of decreasing overall sensitivity.
[0076] Probes used in the FISH analysis may be either RNA or DNA oligonucleotides or polynucleotides and may contain not only naturally occurring nucleotides but their analogs like digoxygenin dCTP, biotin dcTP 7-azaguanosine, azidothymidine, inosine, or uridine. Other useful probes include peptide probes and analogues thereof, branched gene DNA, peptidometics, peptide nucleic acid (PNA) and/or antibodies.
[0077] Probes should have sufficient complementarity to the target nucleic acid sequence of interest so that stable and specific binding occurs between the target nucleic acid sequence and the probe. The degree of homology required for stable hybridization varies with the stringency of the hybridization medium and/or wash medium. Preferably, completely homologous probes are employed in the present invention, but persons of skill in the art will readily appreciate that probes exhibiting lesser but sufficient homology can be used in the present invention [see for e.g. Sambrook, J., Fritsch, E. F., Maniatis, T., Molecular Cloning A Laboratory Manual, Cold Spring Harbor Press, (1989)]. “Complementary,” when referring to two nucleotide sequences, means that the two sequences of nucleotides are capable of hybridizing, preferably with less than 25%, more preferably with less than 15%, even more preferably with less than 5%, most preferably with no mismatches between opposed nucleotides. Preferably the two molecules will hybridize under conditions of high stringency.
[0078] As used herein, stringency of hybridization may be determined as follows or using other protocols known to one of skill in the art:
[0079] 1) high stringency: 0.1.times.SSPE, 0.1% SDS, 65° C.
[0080] 2) medium stringency: 0.2.times.SSPE, 0.1% SDS, 50° C.
[0081] 3) low stringency: 1.0.times.SSPE, 0.1% SDS, 50° C.
[0082] It is understood that equivalent stringencies may be achieved using alternative buffers, salts and temperatures.
[0083] One of skill in the art will appreciate that the choice of probe will depend on, for example, the genetic expression or abnormality of interest. Genetic abnormalities that can be detected by this method include, but are not limited to, amplification, translocation, deletion, addition and the like. Probes may also be generated and chosen by several means including, but not limited to, mapping by in situ hybridization, somatic cell hybrid panels, or spot blots of sorted chromosomes; chromosomal linkage analysis; or cloned and isolated from sorted chromosome libraries from human cell lines or somatic cell hybrids with human chromosomes, radiation somatic cell hybrids, microdissection of a chromosome region, or from yeast artificial chromosomes (YACs) identified by PCR primers specific for a unique chromosome locus or other suitable means like an adjacent YAC clone. Probes may be, for example, genomic DNA, cDNA, or RNA cloned in a plasmid, phage, cosmid, YAC, Bacterial Artificial Chromosomes (BACs), viral vector, or any other suitable vector. Probes may be cloned or synthesized chemically by conventional methods.
[0084] Probes are preferably labeled with a fluorophore. Examples of fluorophores include, but are not limited to, rare earth chelates (europium chelates), Texas Red, rhodamine, fluorescein, dansyl, phycocrytherin, phycocyanin, spectrum orange, spectrum green, and/or derivatives of any one or more of the above. Multiple probes used in the assay may be labeled with more than one distinguishable fluorescent or pigment color. These color differences provide a means to identify, for example, the hybridization positions of specific probes. Moreover, probes that are not separated spatially can be identified by a different color light or pigment resulting from mixing two other colors (e.g., light red+green=yellow) pigment (e.g., blue+yellow=green) or by using a filter set that passes only one color at a time.
[0085] Probes can be labeled directly or indirectly with the fluorophore, utilizing conventional methodology. Additional probes and colors may be added to refine and extend this general procedure to include more genetic abnormalities or serve as internal controls.
[0000] Analysis of Fluorescence and Technical Applications
[0086] After processing for FISH, analysis may be performed by standard techniques of fluorescence [see for e.g. Ploem and Tanke Introduction to Fluorescence Microscopy, New York, Oxford University Press (1987)].
[0087] In order to correlate cellular morphology with FISH, one may use a computer-driven, motorized stage which stores location of coordinates. This may be used to evaluate the same area by two different analytical techniques. For example, color images of the morphologically stained areas may be captured and saved using a computer-assisted cooled CCD camera. The same section may be subsequently taken through the FISH procedure, the stored locations recalled, and the designated areas scored for the presence of fluorescent nuclear signals.
[0088] Typically, hundreds of cells are scanned in a tissue sample and quantification of the specific target nucleic acid sequence is determined in the form of fluorescent spots, which are counted relative to the number of cells. Deviation of the number of spots in a test cell from a norm may be indicative of a malignancy or a predisposition to a malignancy, disease, or other abnormality. The relative number of abnormal cells to the total cell sample population may also indicative of the extent of the condition or abnormality. In addition, using family health histories and/or genetic screening, it is possible to estimate the probability that a particular subject has for developing certain types of disease. Those subjects that have been identified as being predisposed to, for example, developing a particular form of disease can be monitored or screened to detect early evidence of disease. Upon discovery of such evidence, early treatment can be undertaken to combat the disease. Similarly, those subjects who have already developed, for example, a malignancy and who have been treated to remove the cancer or are otherwise in remission are particularly susceptible to relapse and reoccurrence, including the metastasis of tumors. Such subjects can be monitored and screened using the presently disclosed methods to detect evidence of metastasis and upon discovery of such evidence, immediate treatment can be undertaken to combat the disease.
[0089] Thus, in infected whole blood smears, cell lines or tissue sections, endogenous nucleic acids or nucleic acids of pathogenic organisms such as bacteria, virus, protozoan, or fungi, can be detected within the infected cells. Such methods provide useful diagnostic and scientific information since the presence or absence of a specific nucleic acid can directly or indirectly correlate with one or more cells of observable structure and morphology, and, in this way, provide a basis for clinical diagnosis and prognosis.
[0090] For example, scientists, physicians and other investigators attempt to develop compounds or other agents that will have effects on specific molecular pathways in cells that will have a therapeutic effect on disease. The therapeutic action of many of these compounds is expected to result in (directly or indirectly) either suppressing the expression of a gene(s) or, alternatively, the promotion of the expression of that gene(s). In turn, the targeted gene(s), through its suppression or promotion, can either suppress or promote the expression of other genes in molecular pathways that influence the course of disease. Therefore, in order to assess the effect(s) of a putative therapeutic compound or identify toxic effects of a test compound, it would useful to determine if that compound does indeed have the effect of suppressing or promoting genes that are in molecular pathways believed to be involved in the pathogenesis of disease or, in the case of a potential toxic compound, it would be useful to determine if that compound is involved in pathways related to toxic responses.
[0091] The earliest expression of a gene is pre-mRNA, with the secondary expression resulting in the processing of that pre-mRNA to create mRNA. Therefore, it would be useful to measure pre-mRNA and/or mRNA related to the genes of interest in disease pathogenesis. Such measurements could indicate if a putative compound may indeed work and provide investigators with evidence of whether to proceed with the discovery and development process regarding a specific compound or terminate that process.
[0092] The methods of this invention are suitable for use with any specimen obtained from a patient including but not limited to, whole blood, serum, plasma, sputum, urine, breast milk, cerebral spinal fluid, and tissue. These methods are also suitable for detection of a pathogen within the cells of an insect vector. The sample is deposited onto the slide by standard means, and is then fixed onto the slide. The purpose of fixing cells or tissue is to preserve the morphology of the cells or tissue such that RNA is retained within the cellular matrix under the rigorous conditions experienced during in situ hybridization. The preferred method thus utilizes a fixative which is able to preserve and retain nucleic acids of the cell and at the same time cross-link and/or precipitate the proteins in the cellular matrix such that the cell or tissue remains substantially in open configuration for probe penetration and subsequent hybridization.
[0093] There are three main ways in which cells and tissues may be processed to retain their structural organization for subsequent experimentation. These are fixation by cross-linking, fixation by precipitation, and fixation by freezing (cryofixation). Cryofixation, is probably the best technique for cellular preservation, and is often employed for electron microscopy for this reason. It involves rapidly freezing the cells or tissues on a cooled block of heat-conductive metal or rapid plunging into a cold medium, such as liquid nitrogen or freon. Following freezing, the samples may then be treated with a cross-linking reagent, discussed below, in a process called ‘freeze substitution’. The disadvantages of cryofixation are that it typically requires specialized equipment usually unavailable in most laboratories.
[0094] The selection of a specific fixation protocol will be dictated by several factors. First, the fluorescent probe to be used may place restrictions on which treatment may be necessary (i.e. some fixations prevent binding of certain dyes). Second, the size or thickness of a given sample may preclude the use of certain fixatives due to permeability (i.e. a fixative that is unable to penetrate into thick samples will only preserve the outer layers).
[0095] Fixation by cross-linking is a method commonly used for fluorescence microscopy. It involves treating specimens with reagents that penetrate into the cells and tissues and form covalent cross-links between intracellular components. The most commonly used cross-linking agents are aldehydes, which form covalent bonds between adjacent amine-containing groups through Schiff acid-base reaction. These bonds form both inter- and intra-molecularly and are, therefore, very effective fixatives for proteins and nucleic acids. The two most frequently used aldehydes are formaldehyde and glutaraldehyde. Both fixatives have advantages and disadvantages, which will be discussed below. Other aldehydes, such as acrolein, have been used historically, but do not preserve samples as well.
[0096] Glutaraldehyde is a four carbon molecule terminated at both ends by aldehyde groups. It is an extremely efficient fixative, and is widely used by light and electron microscopy for its efficacy in preserving cellular structure. Use of glutaraldehyde does have certain disadvantages, however. First, its comparatively high molecular weight limits its ability to diffuse into thick specimens, such as tissue sections or embryos. This is further exacerbated by the fact that as the tissue is cross-linked by the fixative, its ability to penetrate over time diminishes. For such samples, formaldehyde may be a better option. Second, free aldehyde groups fluoresce efficiently at the same wavelengths as many of the fluorescent probes employed by biologists. As glutaraldehyde possesses two functional groups per molecule, background autofluorescence may be a significant problem in fixed tissues, effectively lowering the probe's signal to noise. This problem may be circumvented by using relatively low concentrations of glutaraldehyde (i.e. less than 1%). Unreacted aldehydes may also be quenched by treating fixed samples with reducing agents, such as sodium borohydride, to reduce free aldehyde groups to alcohols, or by reacting them with exogenous amine-containing reagents, such as ammonium chloride or glycine. In a preferred embodiment of the present invention, the fixed tissue is treated with sodium borohydride to quench auto fluorescence.
[0097] Formaldehyde is probably the most commonly used cross-linking fixative for biological samples. It has a single aldehyde-containing carbon and exists as a gas. Formaldehyde does not cross-link as effectively as glutaraldehyde, and for this reason is rarely used by-itself for electron microscopy. However, its small molecular weight allows it to penetrate cells and tissues rapidly, making it a choice fixative for thicker samples and autofluorescence of unreacted aldehyde groups is not usually a problem.
[0098] Methods for detecting a target nucleic acid fragment directly from a specimen are comprised of multiple steps which are typically performed in the following order. A specimen, usually obtained from a patient, is fixed and embedded in paraffin. The embedded tissue may be sectioned for Tissue-FISH. The sample is treated in keeping with the inventive method (i.e. the sample is pressure cooked and treated with ammonia-ethanol and sodium borohydride). The nucleic acids of the sample are then incubated with a labeled probe specific for the target nucleic acid fragment, under conditions appropriate for hybridization. The probe is comprised of a nucleic acid sequence which is complementary to the target nucleic acid on the tissue under stringent conditions. The probe is then visualized and quantified if necessary. This information can then be compared to a baseline or to another cell or any other desired application as would be apparent to one of skill in the art.
[0099] The quantity of the total probe used is a predetermined amount which should exceed the estimated amount of the available target believed to be within the sample (about 100:1) in order to drive the hybridization reaction efficiently and to promote a high rate of probe:target annealing. The labeled probe is incubated with the nucleic acids of the fixed sample. In one embodiment, the labeled probe is generally added in solution onto the sample. Conditions appropriate for hybridization are solutions which provide the appropriate buffered environment. The specific concentration of hybridization buffer varies with the nucleic acid sequence and length of the probe. The exact concentration of buffer used is dependent on the Tm of the probe, probe sequence, probe length, and hybridization temperature, and can be determined by one of skill in the art through the course of no more than routine experimentation.
[0100] After hybridization is complete, the non-hybridized probe is typically rinsed from the sample, generally by applying a series of stringent washes with a wash buffer. It is within the means of those skilled in the art to determine appropriate wash buffers. In one embodiment, the wash buffer is 0.3 M sodium chloride, 0.03 M sodium citrate, and 0.5% NP40. In another embodiment, the wash buffer is phosphate buffered saline (PBS). In a further embodiment, the wash is formamide/sodium citrate.
[0101] After rinsing, the sample may be counterstained to allow the visualization of organisms within the cells, which contain the hybridized probes. This staining step is generally applied when a fluorescent-labeled probe is used to detect nucleic acids, which are specific for a pathogen. Counterstaining the cells or tissue concurrently with the in situ hybridization assay enhances the method by allowing a clearer determination of the location of the target nucleic acid within the sample. Such information helps, for example, to provide a clearer determination of background hybridization. In one embodiment, the counterstain is DAPI, Toto-3, To-pro-3, Sytox Green, Yoyo-1, Propidium Iodide, Bobo-3 or Evans Blue.
[0102] In one embodiment, any labeled probe that is hybridized to the nucleic acid of the fixed sample is then visually detected by microscopy. The presence of labeled probe within the sample is an indication of the presence of the target nucleic acid fragment. The sensitivity of this method has been determined to detect as little as 10 copies of target nucleic acid.
[0103] It should be appreciated that the use of formamide or GuSCN in the hybridization fluid allows hybridization to be carried out at a much lower temperature than standard hybridization protocols. Hybridization of an average probe specifically to the target (and not to host cells) in aqueous hybridization fluid such as sodium chloride would generally require a temperature of 60-65° C. The same hybridization performed at 42° C. in hybridization buffer described above, would provide specificity.
[0104] The probe is detected by means suitable for the specific moiety used to label the probe. In one embodiment, the marker moiety is a fluorophore. In a preferred embodiment, the fluorophore is FITC, Fluo-3, 5 hexadecanoyl fluorescein, Cy2, fluorX, Cy3, Cy3.5, Cy5, Cy5.5, Cy7, fluorescein and Texas Red. For example, the preferred method for detecting a fluorescent-labeled probe, employs special filters such as a blue filter (fluorescent labeled probe) and a green filter (for rhodamine-X or Texas red labeled probe).
[0105] The methods of this invention may be used for simultaneous detection of different transcripts in a single clinical sample by performing one reaction with a labeled probe, which is comprised of a plurality of different nucleic acid sequences, each labeled with a different marker moiety. For simultaneous detection, the probes that are specific for the different nucleic acids commonly present in a clinical specimen can be designed such that the Tm values of all the probe sequences are very similar. Each specific probe is then labeled with a different detectable moiety (e.g. different fluorescent moieties). Hybridization is performed with the multiple components of the probe. The hybridized sample is processed as described above and the sample is observed by means appropriate for detection of the different labeled probes (e.g. viewed using appropriate filters if different fluorescent moieties are used) to detect which transcripts are detected in the sample.
[0106] It will be recognized by practitioners ordinarily skilled in this art that the novel in situ hybridization protocol described herein is compatible with all previously known methods of detection as well as the one described herein. It is expected that the reagents described in the present invention may be provided in a kit form to practice the protocol, which has been optimized for simplicity and for compatibility with a wide variety of detection methods. It is also expected that such prepared kits containing specifically prepared reagents and probes, will be applicable in clinical/diagnostic laboratories, where the ability to detect the presence or absence of specific nucleic acids would serve to positively or negatively identify pathological states characterized by the presence of specific genes. In a preferred embodiment, such methods would be designed for use with fixed treated tissue and would comprise reagents necessary therefore.
[0107] Accordingly, in one embodiment, the invention provides a method for identifying a potential therapeutic agent which modulates a level of a gene's expression in a tissue, the method comprising:
(a) preparing at least a first and second sample from at least a first and second tissue according to the inventive process described herein, wherein the samples are identical with the exception that the first tissue has been sampled from a cell-line, animal or human that has been treated with the agent whereas the second tissue has been sampled from a cell-line, animal, or human that has not; (b) detecting the level of the gene's transcription in the at least first and second tissue using FISH,
wherein a difference in the detected levels indicates that the agent modulates the level of the gene's expression. In one preferred embodiment, the modulation of the gene's expression is comprised in a pathway associated with therapeutic effects on the cell-line, animal, or human. Identification of a favorable response to a particular agent may be critical in assessing potential therapeutic effects of candidate therapeutic agents. In another preferred embodiment, the modulation of the gene's expression is comprised in a pathway associated with toxic effects on the cell line, animal, or human. Identification of a toxic response to a particular agent may be critical in assessing potential detrimental effects of candidate therapeutic agents.
[0110] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the present application, including definitions will control. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference.
[0111] Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the invention, preferred methods and materials are described below. The materials, methods, and examples are illustrative only and not intended to be limiting. Other features and advantages of the invention will be apparent from the detailed description and the claims.
EXAMPLES
Example 1
In Situ Hybridization
[0000] Pretreatment
[0112] 5 μm paraffin-embedded sections were dried at 37° C. for about 1 hour and then transferred to a decloaker chamber for 30 minutes where they were deparaffinized and antigen-retrieved using a solution that allows both steps to occur at the same time. The slides were then washed in PBS for 10 minutes, incubated for 20 minutes in 0.25% ammonia-ethanol at room temperature (RT), and then incubated for 50 minutes in 5% sodium borohydride in PBS at RT. The slides were then washed twice with tap water and then in PBS for 5 minutes.
[0000] Hybridization
[0113] The slides were incubated for at least 15 minutes in a prehybridization solution of formamide/2×SSC at RT. The slides were then hybridized with a specific set of probes at 37° C. in a humidity chamber from 3 hours to overnight. The slides then underwent several post-hybridization washes which included:
Formamide/2×SSC for 20 minutes at 37° C.
[0115] 1×SSC at RT on a shaker for 15 minutes
[0116] 0.5×SSC at RT on a shaker for 15 minutes
[0117] The slides were then washed in PBS/MgCl 2 for 5 minutes and then the nuclei were counterstained using a DAPI solution (Blue). The slides were rinsed in PBS/MgCl 2 for 5 minutes to remove the excess solution, and then mounted and coverslipped using an antifade mounting solution. The slides were kept at −20° C. until the actual reading under the fluorescent microscope.
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This invention relates to methods for the detection of one or more mRNA transcripts in paraffin-embedded tissue by “mRNA liberation in fixed-treated tissue or ‘MLIFTT’”. This method includes treating the tissue with ammonia-ethanol and sodium borohydride combined with pressure cooking of the tissue. The chemical treatments reduce the tissue autofluorescence and the physical treatments overcome the interference created by the fixation-induced chemical bonds. The methods of the present invention can be utilized to identify a plurality of mRNA transcripts in a microarray format.
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[0001] This application is a continuation of U.S. patent application Ser. No. 13/048,445, filed Mar. 15, 2011, now U.S. Pat. No. 8,474,476, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/313,902, filed Mar. 15, 2010, and U.S. Provisional Patent Application Ser. No. 61/313,918, filed Mar. 15, 2010, the entire disclosures of which are incorporated by reference herein.
[0002] This application is also related to U.S. Pat. No. 8,042,565, U.S. Pat. No. 7,472,718, and U.S. Pat. No. 7,730,901, the entire disclosures of which are incorporated by reference herein.
FIELD OF THE INVENTION
[0003] Embodiments of the present invention are generally related to contamination proof hydrants that employ a venturi that facilitates transfer of fluid from a self-contained water storage reservoir.
BACKGROUND OF THE INVENTION
[0004] Hydrants typically comprise a head interconnected to a water source by way of a vertically oriented standpipe that is buried in the ground or interconnected to a fixed structure, such as a roof. To be considered “freeze proof” hydrant water previously flowing through the standpipe must be directed away from the hydrant after shut off. Thus many ground hydrants 2 currently in use allow water to escape from the standpipe 6 from a drain port 10 located below the “frost line” 14 as shown in FIG. 1 .
[0005] Hydrants are commonly used to supply water to livestock that will urinate and defecate in areas adjacent to the hydrant. It follows that the animal waste will leach into the ground. Thus a concern with freeze proof hydrants is that they may allow contaminated ground water to penetrate the hydrant through the drain port when the hydrant is shut off. More specifically, if a vacuum, i.e., negative pressure, is present in the water supply, contaminated ground water could be drawn into the standpipe and the associated water supply line. Contaminants could also enter the system if pressure of the ground water increases. To address the potential contamination issue, “sanitary” yard hydrants have been developed that employ a reservoir that receives water from the standpipe after hydrant shut off.
[0006] There is a balance between providing a freeze proof hydrant and a sanitary hydrant that is often difficult to address. More specifically, the water stored in the reservoir of a sanitary hydrant could freeze which can result in hydrant damage or malfunction. To address this issue, attempts have been made to ensure that the reservoir is positioned below the frost line or located in an area that is not susceptible to freezing. These measures do not address the freezing issue when water is not completely evacuated from the standpipe. That is, if the reservoir is not adequately evacuated when the hydrant is turned on, the water remaining in the reservoir will effectively prevent standpipe water evacuation when the hydrant is shut off, which will leave water above the frost line.
[0007] To help ensure that all water is evacuated from the reservoir, some hydrants employ a venturi system. A venturi comprises a nozzle and a decreased diameter throat. When fluid flows through the venturi a pressure drop occurs at the throat that is used to suction water from the reservoir. That is, the venturi is used to create an area of low pressure in the fluid inlet line of the hydrant that pulls the fluid from the reservoir when fluid flow is initiated. Sanitary hydrants that employ venturis must comply with AS SE-1057, ASSE-0100, and ASSE-0152 that require that a vacuum breaker or a backflow preventer be associated with the hydrant outlet to counteract negative pressure in the hydrant that may occur when the water supply pressure drops from time-to-time which could draw potentially contaminated fluid into the hydrant after shut off. Internal flow obstructions associated with the vacuum breakers and backflow preventers will create a back pressure that will affect fluid flow through the hydrant. More specifically, common vacuum breakers and backflow preventers employ at least one spring-biased check valve. When the hydrant is turned on spring forces are counteracted and the valve is opened by the pressure of the fluid supply, which negatively influences fluid flow through the hydrant. In addition an elongated standpipe will affect fluid flow. These sources of back pressure influence flow through the venturi to such a degree that a pressure drop sufficient to remove the stored water from the reservoir will not be created. Thus to provide fluid flow at a velocity required for proper functioning of the venturi, fluid diverters or selectively detachable backflow preventers, i.e., those having a quick disconnect capability, have been used to avoid the back pressure associated with the vacuum breakers of backflow preventers. In operation, as shown in FIG. 2 , the diverter is used initially for about 45 seconds to ensure reservoir evacuation. Then, the diverter is disengaged so that the water will flow through the backflow preventer or vacuum breaker. The obvious drawback of this solution is that the diverter must be manually actuated and the user must allow water to flow for a given amount of time, which is wasteful.
[0008] Further, as the standpipe gets longer it will create more backpressure, i.e., head pressure, that reduces the flow of water through the venturi, and at some point a venturi of any design will be unable to evacuate the water in the reservoir. That is, the amount of time it takes for a hydrant to evacuate the water into the reservoir depends on the height/length of the standpipe as well as the water pressure. The evacuation time of roof hydrants of embodiments of the present invention, which has a 42″ standpipe, is 5 seconds at 60 psi. The evacuation time will increase with a lower supply pressure or increased standpipe length or diameter. Currently existing hydrants have evacuation times in the 30 second range.
[0009] Another way to address the fluid flow problem caused by vacuum breakers is to provide a reservoir with a “pressure system” that is capable of holding a pressure vacuum that is used to suction water from the standpipe after hydrant shut off. During normal use the venturi will evacuate at least a portion of the fluid from the reservoir. Supply water is also allowed to enter the reservoir which will pressurize any air in the reservoir that entered the reservoir when the reservoir was at least partially evacuated. When flow through the hydrant is stopped, the supply pressure is cut off and the air in the reservoir expands to created a pressure drop that suctions water from the standpipe into the reservoir. If the vacuum produced is insufficient, which would be attributed to incomplete evacuation of the reservoir, water from the standpipe will not drain into the reservoir and water will be left above the frost line.
[0010] Other hydrants employ a series of check valves to prevent water from entering the reservoir during normal operations. Hydrants that employ a “check system” uses a check valve to allow water into or out of the reservoir. When the hydrant is turned on, the check valve opens to allow the water to be suctioned from the reservoir. The check also prevents supply water from flowing into the reservoir during normal operations, which occurs during the operation of the pressure vacuum system. When the hydrant is shut off, the check valve opens to allow the standpipe water to drain into the reservoir. One disadvantage of a check system is that it requires a large diameter reservoir to accommodate the check valve. Thus a roof hydrant would require a larger roof penetration and a larger hydrant mounting system, which may not be desirable.
[0011] Another issue associated with both the pressure vacuum and check systems is that there must be a passageway or vent that allows air into the reservoir so that when a hydrant is turned on, the water stored in the reservoir can be evacuated. If the reservoir was not exposed to atmosphere, the venturi would not create sufficient suction to overcome the vacuum that is created in the reservoir.
SUMMARY OF THE INVENTION
[0012] It is one aspect of embodiments of the present invention to provide a sanitary and freeze proof hydrant that employs a venturi for suctioning fluid from a fluid storage reservoir. As one of skill in the art will appreciate, the amount of suction produced by the venturi is a function of geometry. More specifically, the contemplated venturi is comprised of a nozzle with an associated throat. Water traveling through the nozzle creates an area of low pressure at or near the throat that is in fluid communication with the reservoir. In one embodiment, the configuration of the nozzle and throat differs from existing products. That is, the contemplated nozzle is configured such that the venturi will operate in conjunction with a vacuum breaker, a double check backflow preventer, or a double check backflow prevention device as disclosed in U.S. Patent Application Publication No. 2009/0288722, which is incorporated by reference in its entirety herein, without the need for a diverter. Preferably, embodiments of the present invention are used in conjunction with the double check backflow prevention device of the '722 publication as it is less disruptive to fluid flow than the backflow preventers and vacuum breakers of the prior art.
[0013] While the use of a venturi is not new to the sanitary yard hydrant industry, the design features of the venturi employed by embodiments of the present invention are unique in the way freeze protection is provided. More specifically, current hydrants employ a system that allows water to bypass a required vacuum breaker. For example, the Hoeptner Freeze Flow Hydrant employs a detachable vacuum breaker and the Woodford Model S3 employs a diverter. Again, fluid diversion is needed so that sufficient fluid flow is achieved for proper venturi functions. The venturi design of sanitary hydrants of the present invention is unique in that the venturi will function properly when water flows through the vacuum breaker or double check backflow preventer—no fluid diversion at the hydrant head is required. This allows the hydrant to work in a way that is far more user friendly, because the hydrant is able to maintain its freeze resistant functionality without requiring the user to open a diverter, for example. Embodiments of the present invention are also environmentally friendly as resources are conserved by avoiding flowing water out of a diverter.
[0014] It is another aspect of the embodiments of the invention is to provide a hydrant that operates at pressures from about 20 psi to 125 psi and achieves a mass flow rate above 3 gallons per minute (GPM) at 25 psi, which is required by code. One difficult part of optimizing the flow characteristics to achieve these results is determining the nozzle diameter. It was found that a throat diameter change of about 0.040 inches would increase the mass flow rate by 2 GPM. That same change, however, affects the operation of the venturi. For example, hydrants with a nozzle diameter of 0.125 inches will provide acceptable reservoir evacuation but would not have the desired mass flow rate. A 0.147 inch diameter nozzle will provide an acceptable mass flow rate, but reservoir evacuation time was sacrificed. In one embodiment of the present invention a venturi having a nozzle diameter of about 0.160 inches is employed.
[0015] It is another aspect of the present invention to provide a nozzle having an exit angle that facilitates fluid flow through the venturi. More specifically, the nozzle exit of one embodiment possesses a gradual angle so that fluid flowing through the venturi maintains fluid contact with the surface of the nozzle and laminar flow is generally achieved. In one embodiment the exit angle is between about 4 to about 5.6 degrees. For example, nozzle exit having very gradual surface angle, e.g. 1-2 degrees, will evacuate the reservoir more quickly, but would require an elongated venturi. Thus, an elongated venturi may be used to reduce back pressure associated with the venturi, but doing so will add cost. The nozzle inlet may have an angle that is distinct from that of the exit to facilitate construction of the venturi by improving the machining process.
[0016] It is thus one aspect of the present invention to provide a sanitary hydrant, comprising: a standpipe having a first end and a second end; a head for delivering fluid interconnected to said first end of said standpipe; a fluid reservoir associated with said second end of said standpipe; a venturi positioned within said reservoir and interconnected to said second end of said standpipe, said venturi comprised of a first end, which is interconnected to said standpipe, and a second end associated with a fluid inlet valve with a throat between said first end and said second end of said venturi; a bypass tube having a first end interconnected to a location adjacent to said first end of said venturi and a second end interconnected to a bypass valve, said bypass valve also associated with said second end of said venturi, wherein when said bypass valve is opened, fluid flows from said inlet valve, through said bypass tube, through said standpipe, and out said hydrant head; and wherein when said bypass valve is closed, fluid flows through said venturi, thereby creating a pressure drop adjacent to said throat that communicates with said reservoir to draw fluid therefrom.
[0017] It is another aspect to provide a method of evacuating a sanitary hydrant, comprising: providing a standpipe having a first end and a second end; providing a head for delivering fluid interconnected to said first end of said standpipe; providing a fluid reservoir associated with said second end of said standpipe; providing a venturi positioned within said reservoir and interconnected to said second end of said standpipe, said venturi comprised of a first end, which is interconnected to said standpipe, and a second end associated with a fluid inlet valve with a throat between said first end and said second end of said venturi; providing a bypass tube having a first end interconnected to a location adjacent to said first end of said venturi and a second end interconnected to a bypass valve, said bypass valve also associated with said second end of said venturi, wherein when said bypass valve is opened, fluid flows from said inlet valve, through said bypass tube, through said standpipe, and out said hydrant head; and wherein when said bypass valve is closed, fluid flows through said venturi, thereby creating a pressure drop adjacent to said throat that communicates with said reservoir to draw fluid therefrom initiating fluid flow through said head by actuating a handle associated therewith; actuating a bypass button that opens the bypass valve such that fluid is precluded from entering said venturi; actuating said bypass button to close said bypass valve; flowing fluid through said venturi; evacuating said reservoir; ceasing fluid flow through said hydrant; and draining fluid into said reservoir.
[0018] The Summary of the Invention is neither intended nor should it be construed as being representative of the full extent and scope of the present invention. Moreover, references made herein to “the present invention” or aspects thereof should be understood to mean certain embodiments of the present invention and should not necessarily be construed as limiting all embodiments to a particular description. The present invention is set forth in various levels of detail in the Summary of the Invention as well as in the attached drawings and the Detailed Description of the Invention and no limitation as to the scope of the present invention is intended by either the inclusion or non-inclusion of elements, components, etc. in this Summary of the Invention. Additional aspects of the present invention will become more readily apparent from the Detail Description, particularly when taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the general description of the invention given above and the detailed description of the drawings given below, serve to explain the principles of these inventions.
[0020] FIGS. 1A-1C are a depiction of the operation of a hydrant of the prior art;
[0021] FIGS. 2A-2C are a series of figures depicting the use of a flow diverter of the prior art;
[0022] FIG. 3 is a cross section of a venturi of the prior art;
[0023] FIG. 4 is a perspective view of a venturi system employed by the prior art;
[0024] FIG. 5 is a perspective view of one embodiment of the present invention;
[0025] FIG. 6 is a detailed view of the venturi system of the embodiment of FIG. 5 ;
[0026] FIG. 7 is a perspective view similar to that of FIG. 6 wherein the reservoir has been omitted for clarity;
[0027] FIG. 8 is a cross sectional view of a venturi system that employs a bypass tube of one embodiment of the present invention;
[0028] FIG. 9 is a cross sectional view of a bypass valve used in conjunction with the embodiment of FIG. 5 shown in an open position;
[0029] FIG. 10 shows the bypass valve of FIG. 9 in a closed position;
[0030] FIG. 11 is a top perspective view of one embodiment of the present invention showing a bypass button and an electronic reservoir evacuation button;
[0031] FIG. 12 is a graph showing sanitary hydrant comparisons;
[0032] FIG. 13 is a perspective view of a venturi system of another embodiment of the present invention;
[0033] FIG. 14 is a detailed cross sectional view of FIG. 13 showing the check valve in a closed position when the hydrant is on;
[0034] FIG. 15 is a detailed cross sectional view of FIG. 13 showing the check valve in an open position when the hydrant is off;
[0035] FIG. 16 is a cross sectional view showing a hydrant of another embodiment of the present invention;
[0036] FIG. 17 is a detail view of FIG. 16 ;
[0037] FIG. 18 is a detail view of FIG. 17
[0038] FIG. 19 is a cross section of another embodiment of the present invention; and
[0039] FIG. 20 is a table showing a comparison of various hydrant assemblies and the operation cycle of each.
[0040] It should be understood that the drawings are not necessarily to scale, but that relative dimensions nevertheless can be determined thereby. In certain instances, details that are not necessary for an understanding of the invention or that render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein.
[0041] To assist in the understanding of one embodiment of the present invention the following list of components and associated numbering found in the drawings is provided herein:
[0000]
#
Component
2
Hydrant
4
Head
5
Handle
6
Standpipe
10
Drain port
14
Frost line
18
Venturi
22
Diverter
26
Vacuum breaker
30
Siphon tube
34
Check valve
36
Outlet
37
Venturi vacuum inlet and drain port
38
Hydrant inlet valve
42
Bypass
46
Bypass button
50
Casing cover
54
Piston
56
Bypass valve
57
Control rod
58
Secondary spring operated piston
59
Bottom surface
60
EFR button
64
LED
68
Screen piston
72
Reservoir
76
Check valve piston
80
Vent
DETAILED DESCRIPTION
[0042] The venturi 18 and related components used in the hydrants of the prior art is shown in FIGS. 3 and 4 and functions when the hydrant issued in conjunction with a vacuum breaker and a diverter. The diverter is needed to allow the venturi to work properly in light of the flow obstructions associated with the vacuum breaker. A typical on/off cycle for this hydrant (see also FIG. 2 ) requires that the user open the hydrant to cause water to exit the diverter 22 and not the vacuum breaker 26 . As the water flows out of the diverter 22 , a vacuum is created that draws water through a siphon tube 30 and check valve 34 , which evacuates the reservoir (not shown). Flowing water through the diverter 22 for about 30 to 45 seconds will generally evacuate the reservoir. Next, as shown in FIG. 2 , the diverter 22 is pulled down to redirect the water out of the vacuum breaker 26 . The vacuum breaker 26 allows the hydrant 2 to be used with an attached hose and/or a spray nozzle as the vacuum breaker 26 will evacuate the head when the hydrant 2 is shut off, thereby making it frost proof. When the water is flowing out of the vacuum breaker 26 the venturi 18 will stop working and the one-way check valve 34 will prevent water from entering the reservoir. Once the hydrant is shut off, the water in the standpipe 6 will drain through a venturi vacuum inlet and drain port 37 that is in fluid communication with the reservoir similar to that disclosed in U.S. Pat. No. 5,246,028 to Vandepas, which is incorporated by reference herein. The check valve 34 is also pressurized when the hydrant is turned off because the shut off valve 38 is located above the check valve 34 .
[0043] A venturi assembly used in other hydrants that employ a pressurized reservoir also provides a vacuum only when water flows through a diverter. A typical on/off cycle for a hydrant that uses this venturi configuration is similar to that described above, the exception being that a check valve that prevents water from entering the reservoir is not used. When the diverter is transitioned so water flows through the vacuum breaker, the backpressure created thereby will cause water to fill and pressurize the reservoir, which prevents water ingress after hydrant shut off. As the reservoir is at least partially filled with water during normal use, the user needs to evacuate the hydrant after shut off by removing any interconnected hose and diverting fluid for about 30 seconds, which will allow the venturi to evacuate the water from the reservoir.
[0044] A hydrant of embodiments of the present invention shown in FIGS. 5-11 which may employ a venturi with an about ⅛″ diameter nozzle. To account for the decrease in mass flow and associated back pressure that affects the functionality of the venturi described above, a bypass 42 is employed. More specifically, the bypass 42 maintains the flow rate out of the hydrant head 4 and allows for water to be expelled from the head 4 at the expected velocity. Fluid bypass is triggered by actuating a button 46 located on the casing cover 50 as shown in FIG. 11 . When the hydrant is turned on the user pushes the bypass button 46 that will in turn move a bypass piston 54 of a bypass valve 56 into the open position as shown in FIG. 9 . This will allow water to bypass the venturi 2 and re-enter the standpipe above the restriction caused by the venturi. The increased flow rate is greater than could be achieved with a venturi alone, even if the diameter of the venturi nozzle was increased.
[0045] While the bypass allows the mass flow rate to increase greatly, it also causes the venturi to stop creating a vacuum that is needed to evacuate the reservoir. Before normal use, the bypass piston 54 is closed as shown in FIG. 10 . Similar to the system described in FIG. 16 below, the venturi 18 and associated bypass 42 are associated with a control rod 57 that is associated with the hydrant handle 5 . Opening of the hydrant transitions the control rod 57 upwardly, which pulls the venturi 18 and associated bypass 42 upwardly and opens the hydrant inlet valve 38 to initiate fluid flow. Conversely, transitioning the hydrant handle 5 to a closed position will move the venturi 18 and associated bypass 42 downwardly such that a secondary spring operated piston 58 of the bypass valve 56 well contact a bottom surface 59 of the reservoir. As the secondary spring piston 58 contacts the bottom surface 59 , the bypass valve 54 moves to a closed position as shown in FIG. 10 . Moving the handle 5 to an open position to initiate fluid flow through the hydrant head will separate the secondary spring operated piston 58 from the bottom surface 59 of the reservoir which allows the bypass piston 54 to move to an open position as shown in FIG. 9 when the bypass button 46 is actuated. When the bypass 42 is in the closed position, water is forced to flow through the venturi causing a vacuum to occur, thereby causing the reservoir to be evacuated each time the hydrant is used. After water flows from the vacuum breaker for a predetermined time, the user will actuate the bypass button 46 which opens the bypass valve 56 to divert fluid around the venturi 2 . The secondary spring operated piston 58 , which is designed to account for tolerances making assembly of the hydrant easier. The secondary spring operated piston 58 also makes sure the hydrant will operate properly if there are any rocks or debris present in the hydrant reservoir.
[0046] The venturi 18 of this embodiment can be operated in a 7′ bury hydrant with a minimum operating pressure of 25 psi. The other major exception is the addition of the aforementioned bypass valve 56 that allows the hydrant to achieve higher flow rates.
[0047] In operation with a hose, initially the hose is attached to the backflow preventer 26 or the bypass button is pushed to that the venturi will not operate correctly and the one way check valve 34 will be pressurized in such a way to prevent flow of fluid from the reservoir. After the hydrant is shut off, the hose is removed from vacuum breaker 26 . Next the hydrant 2 is turned on and water flows through the vacuum breaker 26 for about 30 seconds. When there is no hose attached, and the bypass has not been activated, the venturi 18 will create a vacuum that suctions water from the reservoir 72 and making the hydrant frost proof. Thus when the hydrant is later shut off, the check valve piston will move up and force open the one way check valve 37 to allow water in the hydrant to drain into the reservoir. This operation will also reset the bypass valve 56 into the closed position.
[0048] Some embodiments of the present invention will also be equipped with an Electronic Freeze Recognition (EFR) device as shown in FIG. 11 . The EFR includes a button 60 that allows the user to ascertain if the water has been evacuated from the standpipe 6 properly and if the hydrant is ready for freezing weather. The device uses a circuit board in concert with a dual color LED 64 as shown in FIG. 11 to warn the operator of a potential freezing problem. When the EFR button 60 is pushed and the LED 64 glows red it indicates that the hydrant has not been evacuated properly. This informs the operator that the water in the reservoir is above the frost line, and the hydrant needs to be evacuated by the method described above. A green LED 64 indicates the hydrant has been operated properly and the hydrant is ready for freezing weather.
[0049] Flow rates for hydrants of embodiments of the present invention compare favorably with existing sanitary hydrants on the market, see FIG. 12 . The prior art models are compared with hydrants that use a vacuum breaker and hydrants that use a double check backflow preventer. The venturi and related bypass system will meet ASSE 1057 specifications.
[0050] Another embodiment of the present invention is shown in FIGS. 13-15 that does not employ a bypass. Variations of this embodiment employ an about 0.147 to an about 0.160 diameter nozzle, which allows for a flow rate of 3 gallons per minute at 25 psi and evacuation of the reservoir at 20 psi. As this configuration meets the desired mass flow characteristics, a bypass is not required to obtain the mass flow rate, and therefore this hydrant can be produced at a lower cost. This embodiment also employs a dual-use check valve. The check valve is closed by a spring when the hydrant is turned on as shown in FIG. 14 to prevent water from filling the reservoir. Again, when water is flowing through the double check backflow preventer a suction can still be produced to pull water from the reservoir through this check valve. When the hydrant is turned off, a screen piston 68 moves up when it contacts the bottom surface 59 of the reservoir which forces the check valve 34 into the open position as shown in FIG. 15 . This allows the water in the hydrant to drain into the reservoir, thereby making the hydrant freeze resistant. Other embodiments of the present invention employ a venturi to evacuate a reservoir, but do not need a diverter to operate correctly. More specifically, a venturi is provided that will evacuate a reservoir through a double check backflow preventer.
[0051] FIGS. 16-18 show a hydrant of another embodiment of the present invention that is simpler and more user friendly than sanitary hydrants currently in use. This hydrant is limited to a 5′ bury depth and a minimum working pressure of about 40 psi, which maximizes the venturi flow rate potential, while still being able to evacuate the reservoir as water flows through a double check. A one-way check valve 34 is provided that is forced open when the hydrant is shut off as shown in FIG. 17 .
[0052] In operation, this venturi system operates similar to those described above with respect to FIGS. 5-11 . More specifically, the venturi is interconnected to a movable control rod 57 that is located within the standpipe 6 . The handle 5 of the hydrant is thus ultimately interconnected to the venturi 18 and by way of the control rod 57 . To turn on the hydrant, the user moves the handle 5 to an open position, which pulls the control rod 57 upwardly and opens the inlet valve 38 such that water can enter the venturi 18 . Pulling the venturi upward also removes the check valve 34 upwardly such that the screen piston 68 moves away from the bottom surface 59 of the hydrant 2 . To turn the hydrant off, the handle 5 is moved to a closed position which moves the control rod 57 downwardly to move the venturi 18 downwardly to close the inlet valve 38 . Moving the venturi downwardly also transitions the screen piston 68 which opens the check valve 34 . To allow for evacuation reservoir a vent 80 may be provided on an upper surface of the hydrant.
[0053] Generally, this hydrant functions when a hose is attached to the backflow preventer. When the hose is attached, the venturi will not operate correctly and the pressure acting on the one way check valve 34 will prevent water ingress into the reservoir 72 . After the hydrant is shut off, the hose is removed from vacuum breaker, the hydrant must be turned on so that the water can flow through the double check vacuum preventer for about 15 seconds. That is, when there is no hose attached, the venturi will create a vacuum sufficient enough to suction water from the reservoir 72 , and making the hydrant frost proof. When the hydrant is later shut off, the check valve piston 26 will move up and force the one way check valve to an open position which allows the water in the hydrant to drain into the reservoir 72 .
[0054] FIG. 19 shows yet another hydrant of embodiments of the present invention that is designed specifically for mild climate use (under 2′ bury) and roof hydrants. The outer pipe of the roof hydrant is a smaller 1½ diameter PVC, instead of the 3″ used in some of the embodiments described above. This hydrant uses a venturi without a check valve in concert with a pressurized reservoir, a diverter is not used. The operation is the same as described above with respect to hydrant with a pressurized reservoir, with the evacuation of the reservoir being completed after the user detaches the hose.
[0055] FIG. 20 is a table comparing the embodiments of the present invention, which employ an improved venturi of that employ a bypass system, with hydrants of the prior art manufactured by the Assignee of the instant application. The embodiment shown in FIG. 7 , for example, provides an increased flow rate, has an increased bury depth, and can operate at lower fluid inlet pressures. The evacuation time is discussed over the prior art.
[0056] While various embodiments of the present invention have been described in detail, it is apparent that modifications and alterations of those embodiments will occur to those skilled in the art. However, it is to be expressly understood that such modifications and alterations are within the scope and spirit of the present invention, as set forth in the following claims. Further, the invention(s) described herein is capable of other embodiments and of being practiced or of being carried out in various ways. In addition, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. For example, aspects of inventions disclosed in U.S. Pat. Nos. and Published Patent Application Nos. 5,632,303, 5,590,679, 7,100,637, 5,813,428, and 20060196561, all of which are incorporated herein by this reference, which generally concern backflow prevention, may be incorporated into embodiments of the present invention. Aspects of inventions disclosed in U.S. Pat. Nos. 5,701,925 and 5,246,028, all of which are incorporated herein by this reference, which generally concern sanitary hydrants, may be incorporated into embodiments of the present invention. Aspects of inventions disclosed in U.S. Pat. Nos. 6,532,986, 6,805,154, 6,135,359, 6,769,446, 6,830,063, RE39,235, 6,206,039, 6,883,534, 6,857,442 and 6,142,172, all of which are incorporated herein by this reference, which generally concern freeze-proof hydrants, may be incorporated into embodiments of the present invention. Aspects of inventions disclosed in U.S. Pat. Nos. and Published Patent Application Nos. D521,113, D470915, 7,234,732, 7,059,937, 6,679,473, 6,431,204, 7,111,875, D482,431, 6,631,623, 6,948,518, 6,948,509, 20070044840, 20070044838, 20070039649, 20060254647 and 20060108804, all of which are incorporated herein by this reference, which generally concern general hydrant technology, may be incorporated into embodiments of the present invention.
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A freeze resistant sanitary hydrant is provided that employs a reservoir for storage of fluid under the frost line or in an area not prone to freezing. To evacuate this reservoir, a means for altering pressure is provided that is able to function in hydrant systems that employ a vacuum breaker.
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CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
BACKGROUND OF THE INVENTION
The field of the invention is mechanical bridges and more specifically bridges including spans that are openable.
Bridges are required to facilitate convenient rail and vehicular traffic over rivers, streams, dams and the like (hereinafter collectively referred to as rivers). While bridges are necessary, unfortunately bridges can impede passage of vessels along rivers there below. In order to accommodate both rail and vehicular traffic over rivers and travel along the rivers by ships, barges, etc, bridge designers have developed several different mechanical type bridges including one or more bridge spans that can open and close.
One mechanical bridge type is generally referred to as a vertical-lift bridge. A vertical-lift bridge typically includes vertical towers at either end of a bridge span. When positioned for vehicular traffic, the span is in a low position where a top surface is aligned with top surfaces of adjacent bridge spans. To accommodate travel below the bridge span the span can be raised between the towers.
While vertical-lift bridges can accommodate both river and vehicular travel, these bridges have several shortcomings. First, vertical-lift bridges, while accommodating some river travel, still restrict travel as the lifted span remains above the area through which travel occurs. Second, the motors and other mechanical equipment required to lift the bridge span are relatively large and therefore expensive. In addition, because of the mechanics involved with vertical-lift bridges, maintenance costs for vertical lift bridges are relatively high.
Another mechanical bridge type is a swing span bridge. A typical swing span bridge includes a moveable span that pivots about a vertical axis to provide required opening clearance for navigation traffic. Swing spans are typically symmetrical with equal length cantilevers to each side of the vertical axis. Some swing span bridges, however, are configured with unsymmetrical cantilevers that are counterweighted to balance the bridge. Swing span bridges are advantageous as they provide unlimited vertical clearance for river bound traffic when the span is open.
Unfortunately swing spans also have several shortcomings. First, when a swing span is horizontally pivoted into the open position the span ends are generally considered to be navigational hazards. The span ends are directed against movement of water bound traffic and therefore are prone to vessel collision. Thus, often substantial fender systems are required to protect the span and vessels in the area. Second, swing spans typically require twice as much moveable length span as other mechanical span designs to provide the same opening width. This is because, as indicated above, most swing span bridges require equal length span segments cantilevered about the vertical pivot point. Third, the mechanical components required to manipulate the large span sections are generally relatively large and therefore relatively expensive.
Yet one other mechanical bridge type is referred to generally as a bascule type bridge. A typical bascule bridge includes a leaf that pivots about a horizontal axis to provide a required opening and clearance for river bound traffic. Counterweights are usually provided to balance the weight of the span and minimize the operating requirements on the drive machinery. The bascule span bridges provide unlimited vertical clearance when open.
Bascule bridges, like the other bridge types described above, have several shortcomings. First, the counterweight required to balance the bascule span is typically rather large. As most mechanical bridges are relatively low to the water, the counterweights are typically positioned above a span adjacent the moveable span. To support the counterweight these bridge types often require large and expensive overhead framing systems and massive foundations below the spans to handle the overturning moments that occur. Second, the mechanics required to control a bascule bridge are extremely complex and therefore expensive. Third, bascule bridges requiring massive counterweights are relatively unsafe in certain geographic areas that are subject to seismic tremors.
Thus, there is a need for a mechanical bridge that is simple, relatively inexpensive, provides unlimited vertical clearance and that does not require massive overhead or counterweight components.
BRIEF SUMMARY OF THE INVENTION
It has been recognized that a relatively simple bridge design can overcome many of the shortcomings of the prior art bridges described above. To this end, by moving a bridge span essentially within a single vertical plane from a supporting position into a storage position, system mechanics can be greatly simplified without sacrificing safety. To this end, in one embodiment, an openable span is moved laterally from a supporting position and then longitudinally along the side of an adjacent span to open a space for water bound traffic. In another embodiment an adjacent span is removed from its position adjacent an openable span and then the openable span is moved at least in part into the adjacent position to open a space for water bound traffic.
Thus, one object of the invention is to provide a simplified openable bridge design. This object is accomplished by minimizing required vertical span movement. In some embodiments there is no vertical span movement while in other embodiments vertical movement is limited in several ways. First, the vertical distance of movement is minimized. Second the size of the span that has to be moved is limited. To this end, when a first span is vertically moved and then a second span is horizontally moved into the space originally occupied by the first span, the first span is only half as large as the second span and hence a minimally sized span is vertically moved.
Another object is to provide a relatively safe mechanical bridge. To this end, because vertical span movement is limited, above deck structure is minimized. Because above deck structure is minimized bridges constructed according to the present teachings are relatively safe in various environments including those that may be subject to periodic earth quakes and other disruptive natural phenomenon.
Yet one other object is to provide a relatively inexpensive bridge system. Because most span movement is horizontal relatively small motors can be used to move spans on rollers as opposed to lifting the spans.
One other object is to provide a bridge where, when a span is open, the open space can accommodate passage of any vessel there below. To this end the present design has no components that remain above the open space after a span is moved.
Consistent with the above objects and advantages, the present invention includes a bridge assembly comprising first, second and third adjacent piers, the first and second piers defining a first space there between and the second and third piers defining a second space there between, third and fourth spaces above the first and second spaces, respectively, a first bridge span positionable so as to traverse the distance between the first and second piers within the third space, a second bridge span positionable so as to traverse the distance between the second and third piers within the fourth space, a first motivator linked to the first bridge span for moving the first span into and out of the third space and a second motivator linked to the second bridge span for moving at least a portion of the second bridge span from the fourth space to the third space so that at least a portion of the fourth space is unobstructed.
In some embodiments the invention further includes at least one intermediate pier between the second and third piers, the space between the intermediate and third piers being a fifth space, the space above the fifth space being an openable space, the openable space being the portion of the fourth space that is unobstructed when the portion of the second bridge span is moved to the third space. In some cases the first, second, third and intermediate piers are essentially equi-spaced.
In some embodiments roller members are provided between the tops of the piers and the spans thereabove. The rollers may be mounted to the tops of the piers.
In several embodiments the first span has a span width, each of the first and second piers has a pier width that is substantially twice as wide as the span width, first and second in-line sections of the first and second piers, respectively, aligned with the third pier and defining an in-line space, a supporting space above the in-line space, first and second lateral sections of the first and second piers laterally adjacent the first and second in-line sections, respectively, the lateral sections defining a lateral space there between, a receiving space above the lateral space, the first motivator for moving the first span between the supporting space and the receiving space.
In some embodiments the first and second in-line sections and first and second lateral sections comprise one lateral load bearing element and the first span comprises another lateral load bearing element and the assembly further includes a first track mounted to a first one of the lateral load bearing elements and rollers mounted to the second of the lateral load bearing elements, the rollers supportable on the track to facilitate rolling of the first span between the supporting and receiving spaces. Here, the track may be secured to the first span and the rollers may be secured to the tops of the piers.
The assembly may further include an intermediate pier between the second and third piers wherein the second and intermediate piers comprise a longitudinal load bearing element and the second span comprises another longitudinal load bearing element and, wherein, the assembly further includes a second track mounted to a first one of the longitudinal load bearing elements and rollers mounted to the second of the longitudinal load bearing elements, the rollers supportable on the track to facilitate rolling of the second span such that the at least one section moves between the fourth space and the supporting space. The longitudinal load bearing element that includes the second and fourth piers may also includes the first pier.
In some embodiments the first motivator moves the first span between the third space and a space above the third space. In other embodiments the first motivator moves the first span between the third space and the first space.
The second span may include first and second ends, a top and a bottom, the second end adjacent the third pier when the second span is in the fourth space, the assembly further including first and second aligning apparatus at the second end and the top of the third pier, respectively, the second aligning apparatus receiving the first aligning apparatus when the second span is moved into the fourth space so as to align the second span with the third pier. The first aligning apparatus may include a first inclined surface. Similarly, the second aligning apparatus may include a second inclined surface. In addition, the second aligning apparatus may include a guiding roller.
Another embodiment of the invention includes a method for opening a section of a bridge where the bridge includes several spans that are longitudinally arranged along the length of the bridge including at least first and second adjacent spans that, when the bridge is closed, occupy first and second spaces, respectively, the method comprising the steps of moving the first bridge span from the first space, moving at least a segment of the second bridge span from the second space into the first space so that at least a portion of the second space is unobstructed.
According to one embodiment, when the first span is in the first space and the second span is in the second space the first and second spans are aligned longitudinally and, the step of moving the first bridge span includes moving the first span from the first space laterally and wherein the step of moving the second span includes moving the second span longitudinally. In another embodiment, the step of moving the first bridge span includes moving the first span upward and out of the first space.
In yet another embodiment the invention includes a bridge assembly comprising first, second and third adjacent piers, each of the second and third piers including an in-line section and an adjacent lateral section, the in-line sections aligned along a longitudinal axis and the lateral sections aligned along a lateral axis that is essentially parallel to the longitudinal axis, the first pier and second pier in-line section defining a first in-line space there between, the second and third pier in-line sections defining a second in-line space there between, a space adjacent the first in-line space and the second lateral section defining a first lateral space, the second and third lateral sections defining a second lateral space there between, third and fourth in-line spaces above the first and second in-line spaces, respectively, and third and fourth lateral spaces above the first and second lateral spaces, respectively, a first bridge span positioned so as to traverse the distance between the first and second piers within the third in-line space, a second bridge span positionable so as to traverse the distance between the second and third piers within the fourth in-line space, a first motivator linkable to the second bridge span for moving the second span between the fourth in-line space and the fourth lateral space and a second motivator linkable to the second bridge span for moving at least a portion of the second bridge span from the fourth lateral space to the third lateral space so that at least a portion of the fourth lateral space is unobstructed.
Here the assembly may further include at least one intermediate pier between the second and third lateral pier sections, the space between the intermediate and third lateral section being a fifth space, the space above the fifth space being an openable space, the openable space being the portion of the fourth lateral space that is unobstructed when the portion of the second bridge span is moved to the third lateral space. The first lateral section, second lateral section, third lateral section and intermediate pier may be essentially equi-spaced.
The invention further includes a method for opening a section of a bridge where the bridge includes at least first and second adjacent spans that are longitudinally alignable along the length of the bridge and are supported by at least first, second and third piers, each pier including an in-line section and a lateral section laterally positioned with respect to the in-line section, the space between the first and second in-line pier sections being a first in-line space, the space between the second and third in-line pier sections being a second in-line space, the space above the first and second in-line spaces being a third in-line space and the space above the second in-line space being a fourth in-line space, the space between the first and second lateral pier sections being a first lateral space, the space between the second and third lateral pier sections being a second lateral space, the space above the first lateral space being a third lateral space and the space above the second lateral space being a fourth lateral space, when the bridge is closed, the first and second spans occupying the third and fourth in-line spaces, respectively, the method comprising the steps of: moving the second bridge span laterally from the fourth in-line space to the fourth lateral space and moving at least a segment of the second bridge span from the fourth lateral space into the third lateral space so that at least a portion of the fourth space and a portion of the fourth lateral space are unobstructed.
These and other objects, advantages and aspects of the invention will become apparent from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown a preferred embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention and reference is made therefor, to the claims herein for interpreting the scope of the invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIGS. 1 a through 1 d are schematic diagrams illustrating a first embodiment to the present invention;
FIG. 2 is a cross-sectional view taken along the line 2 — 2 of FIG. 1 c;
FIG. 3 is a cross-sectional view taken along the line 3 — 3 of FIG. 1 b;
FIG. 4 is a schematic view taken along the line 4 — 4 of FIG. 3;
FIGS. 5 a through 5 c are schematic views of a second embodiment of the present invention;
FIG. 6 is a schematic cross-sectional view taken along the line 6 — 6 of FIG. 5 a;
FIG. 7 is a schematic cross-sectional view taken along the line 7 — 7 of FIG. 5 a;
FIGS. 8 a through 8 c are schematic diagrams illustrating a third embodiment of the present invention;
FIG. 9 is a cross-sectional view taken along the line 9 — 9 of FIG. 8 a;
FIG. 10 is similar to FIG. 9, albeit illustrating an extended shaft and a raised span;
FIG. 11 is a plan view of the assembly of FIG. 5 b taken along the line 11 — 11 ;
FIG. 12 is a plan view of the assembly of FIG. 5 b taken along the line 12 — 12 ;
FIG. 13 is a view similar to FIG. 11, albeit with a bridge span in a different position and retracted lifts; and
FIG. 14 is a view similar to FIG. 12, albeit with a bridge span in a different position and retracted lifts.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings wherein like reference numerals represent similar elements throughout the several views and, more specifically, referring to FIGS. 1 a through 1 d, a first embodiment of the present invention will be described in the context of a mechanical bridge 10 including a plurality of piers 9 , 12 , 14 , 16 and 18 (only five illustrated) that begins at a first shore 20 and traverses over a river 22 to a shore (not illustrated) opposite shore 20 . Piers 9 , 12 , 14 , 16 and 18 are equi-spaced so as to equally accept load from traffic passing across the bridge thereabove. In addition to piers 9 , 12 , 14 , 16 and 18 , bridge 10 also includes a plurality of spans or bridge sections 24 , 26 , 28 and 32 that traverse the distance between the tops of piers 9 , 12 , 14 , 16 and 18 and provide a deck 34 above river 22 for vehicular travel. Spans 24 , 26 and 32 have essentially identical lengths and traverse the distance between the tops of two adjacent piers. For example, span 26 traverses the distance between the tops of piers 12 and 14 . One special and relatively long span 28 traverses the distance between the tops of three adjacent piers including piers 14 , 16 and 18 . Thus, span 28 is twice as long as any of the other spans in bridge configuration 10 .
Referring specifically to FIG. 1 b, piers 12 and 14 are approximately twice as wide as the other piers that make up bridge 10 . To this end, pier 12 includes an in-line section 38 that is, as the name implies, in-line with other piers (e.g., 16 , 18 , etc.) that form the bridge and a lateral section 40 that is laterally positioned with respect to in-line section 38 . Similarly, pier 14 includes an in-line section 42 and a lateral section 44 . Lateral sections 40 and 44 are aligned to the same side of the in-line sections 38 and 42 and are capable of supporting a bridge span thereabove.
For the purpose of explaining this first embodiment of the invention it is advantageous to define the illustrated piers in a specific manner and also to define various spaces with respect to those piers. To this end, referring still to FIGS. 1 a through 1 d and also to FIG. 1 e, piers 12 , 14 and 18 will generally be referred to as first, second and third piers, pier 16 will be referred to as an intermediate pier, the space 48 between piers 12 and 14 will be referred to as a first space, the space 50 between piers 14 and 18 will be referred to as a second space, the space above first space 48 and, in FIG. 1 a occupied by span 26 , will be referred to as a third space 52 , the space above second space 50 and, in FIG. 1 a, occupied by span 28 , will be referred to as a fourth space 54 , the space between in-line pier sections 38 and 42 will be referred to as an in-line space 41 , the space above in-line space 41 will be referred to as a supporting space 43 , the space between lateral pier sections 40 and 44 will be referred to as a lateral space 45 and the space above lateral space 45 will be referred to as a storage space 47 . In addition, end 64 of span 28 will be referred to as a leading end 64 . In addition, the space between piers 16 and 18 will be referred to as a fifth space 56 and the space thereabove which in FIG. 1 a is occupied by a portion of span 28 will be referred to as an opening space 58 .
With the spaces and piers as defined above and referring to FIGS. 1 a through 1 e, according to this first embodiment of the invention, a section of bridge 10 can be opened to allow river bound traffic to pass through the open section. To this end, according to a first step in the process of clearing a passage through bridge 10 for river bound traffic, first span 26 is removed from supporting space 43 . This is accomplished by moving first span 26 laterally from supporting space 43 to storage space 47 so that lateral sections 40 and 44 of piers 12 and 14 , respectively, support span 26 . This condition is illustrated in FIG. 1 c.
Next, second span 28 is moved longitudinally along the tops of the in-line piers and pier sections so that at least a portion of span 28 is positioned within supporting space 43 . When span 28 is moved in this manner, an opening is created between spans 28 and 32 . By moving span 28 as far as possible into supporting space 43 so that approximately half of span 28 is within space 52 , the entire opening space 58 is rendered unobstructed so that river bound traffic can pass therethrough.
To close the bridge 10 , the above described process is simply reversed. To this end, a first step in closing the open space 58 is to drive span 28 toward span 32 until leading end 64 of span 28 is received and supported on the top of pier 18 . Next, span 26 can be moved form it's lateral position illustrated in FIG. 1 d to its in-line position as illustrated in FIG. 1 b where span 26 traverses the distance between and is support by adjacent in-line pier sections 38 and 42 .
Referring now to FIGS. 1 b and 2 , the mechanism used to slide or move span 26 from the supporting space 43 to the storage space 47 will be described in more detail. To this end, the tops of piers 12 and 14 comprise a first lateral load bearing element while the underside of span 26 comprises a second lateral load bearing element. Rollers are provided on one of the lateral load bearing elements while one or more tracks are provided on the other of the lateral load bearing elements. The rollers and tracks cooperate to facilitate lateral movement of span 26 . Similarly, the tops of piers 14 and 16 comprise a first longitudinal load bearing element and the underside of span 28 comprises a second longitudinal load bearing element. Rollers are provided on one of the longitudinal load bearing elements while one or more tracks are provided on the other of the longitudinal load bearing elements. The rollers and tracks on the longitudinal elements cooperate to facilitate longitudinal movement of span 28 . Specifically, at the tops of each pier 12 and 14 , rollers are provided that facilitate easy movement of span 26 between the supporting space 43 and the storage space 47 . The rollers in this embodiment are identical at the tops of piers 12 and 14 and therefore, only the rollers corresponding to the top of pier 12 will be described in detail. The configuration at the top of pier 12 includes a timber 70 , a pier cap 72 , a first motivator 74 and the first span 26 . Timber 70 includes a lower end (not illustrated) that extends down through the river (see 14 in FIG. 1 a ) and is embedded in the bottom of the river and a top end 76 . Pier cap 72 is a concrete member and is formed about the top end 76 of timber 70 . Although not illustrated in FIG. 2, a plurality of timbers adjacent timber 70 are provided that support cap 72 and the other bridge components thereabove.
Cap 72 forms three roller housings 78 , 80 and 82 that generally face upward. A central roller housing 80 includes a plurality of rollers 84 that form an upward facing roller surface 86 for supporting span 26 thereabove. Lateral roller housings 78 and 82 each support a plurality of rollers 88 , 90 , respectively, that form support surfaces 92 and 94 for guiding and supporting span 26 thereabove.
Surfaces 92 and 94 are tilted in a direction toward central roller housing 80 and therefore restrict movement of span 26 in other than the direction between supporting space 43 and storage space 47 .
Motivator 74 is a motor and is securely mounted to a side 98 of cap 72 (see also FIGS. 1 b through 1 d in this regard). Motor 74 includes a shaft 96 that extends up above cap 72 . At the distal end of shaft 96 a large gear having vertically aligned teeth is mounted.
Span 26 includes a bottom support 104 and various components that form a top support 106 that will be described in more detail below. Bottom support 104 is preferably formed of concrete and has a top surface 102 and a bottom surface 105 . Top surface 102 is essentially flat and provides a support deck for components 106 thereabove. Bottom surface 106 forms three separate roller recesses 108 , 110 and 112 that form roller surfaces 114 , 116 and 118 , respectively. A central roller surface 116 faces downward and is sized so as to receive surface 86 of rollers 84 thereon. Similarly, roller surfaces 114 and 118 are sized and configured so as to receive rollers 88 and 90 , respectively, corresponding to the lateral rollers as illustrated.
A lateral edge 120 of span 26 forms a gear receiving surface having teeth sized to receive the teeth of gear 100 . Edge 120 extends so that the teeth of gear 100 are received within the teeth of edge 120 . While structure 104 is illustrated and described above as being formed of concrete, it should be appreciated that certain of the features may be formed of other more suitable materials used for specialized purpose. For instance, a steel member may be mounted to member 104 that forms the teeth 120 that cooperate with motor 74 to move span 26 . Similarly, flat steel plates may be provided on the surfaces of each of roller surfaces 114 , 116 and 118 that may be greased to facilitate easy movement of rollers there along.
While only a single roller system is illustrated in FIG. 2, it should be appreciated that several roller systems like the one illustrated in FIG. 2 may be provided at the top each of the first and second piers 12 , 14 , respectively. For instance, in one embodiment at least four roller assemblies would be equi-spaced along the top of each of piers 12 and 14 . It should also be appreciated that, because efficient roller systems reduce the amount of power required to move large objects, a relatively small motor 74 should be able to move a span 26 back and forth between the supporting space 43 and storage space 47 . To this end, to move span 26 , motor 74 is driven and applies a force to span 26 that drives the span 26 either into or out of the figure illustrated in FIG. 2 and therefore either toward or away from supporting space 43 (see also FIGS. 1 c and 1 e ).
While first span 26 remains fully supported during movement between supporting space 43 and storage space 47 , as illustrated in the FIG. 1 sequence of drawings, second span 28 is not fully supported during movement between spans 12 and 18 . In other words, span 28 , at certain times during movement, is cantilevered about one or more piers so that at least segments of span 28 are out and over open spaces therebelow. For this reason, a relatively more complex roller system is contemplated to maintain span 28 in a stable configuration during movement. Referring now to FIGS. 1 a through 1 d and also to FIG. 3, the components that are used to construct the top of pier 16 are illustrated. The components in FIG. 3 include two timbers 130 , 132 , a pier cap 134 , a span lower structure 136 , a span upper structure 138 and a second motivator 140 . Timbers 130 and 132 both extend down to the bottom of the river bed to provide support. The top ends 142 and 144 of timbers 130 and 132 , respectively, extend into a lower surface of cap 134 . Cap 134 forms a plurality of roller housings that together cooperate to provide support span 16 and also to provide guidance to span 16 as span 16 is moved. Four roller housings are illustrated including housings 146 , 148 , 150 and 152 . A plurality of rollers 154 are mounted in housing 150 and form a support surface 156 that faces upward. Similarly, a plurality of rollers 158 are mounted in housing 152 and form a support surface 160 that faces upward. A plurality of rollers 162 are mounted in housing 148 and form a vertical guiding surface 164 . A plurality of rollers 166 are mounted in housing 146 and provide a downward facing restraining surface 168 . Other roller assemblies may be provided along the length of cap 134 to facilitate easy movement of span 16 thereabove. Motivator 140 is similar to the motivator 74 described with respect to FIG. 2 and therefore will not be described here in detail. Suffice it to say that a gear 170 extends from the motivator 140 and includes vertically aligned teeth that open, at least to one side, facing an edge 172 of lower structure 136 .
Lower structure 136 includes a top surface 173 for supporting upper structure 138 and a bottom surface 175 . Bottom surface 175 forms a plurality of recesses (e.g., 174 , 176 ) that are sized and positioned so as to receive upward facing rollers that are mounted within cap 134 . Thus, recess 174 forms a load bearing surface 180 that receives support surface 160 while recess 176 forms a load bearing surface 182 that receives support surface 156 . An upper portion of edge 172 contacts guidance surface 164 to restrain lateral movement of span 16 . Upper surface 173 forms an upward facing restraining surface 188 that contacts downward facing restraining surface 168 .
Upper structure 138 includes a plurality of I beams 190 that support a concrete road surface 192 thereabove. A guide rail 194 is provided along a lateral edge of member 192 . Referring also to FIG. 2, configuration of upper structures 106 and 138 is relatively unimportant with respect to what is believed to be novel and therefore are not explained here in detail. Suffice it to say structures 106 and 138 must be rigid and must be securely mounted to the top surfaces of lower structures 104 and 136 , respectively.
As in the case of the roller system illustrated in FIG. 2, the system illustrated in FIG. 3 is only exemplary and a plurality of roller systems like the one illustrated in FIG. 3 would likely be provided at various locations along the tops of piers 14 , 16 and 18 .
Referring now to FIGS. 1 a through 1 d and also to FIG. 4, while span 28 is to be constructed of concrete and steel and other types of rigid materials and therefore should be extremely rigid, where the open space 58 is relatively large (e.g., 60-100 feet), while span 28 is being moved from its open position to the position where space 58 is closed, leading edge 64 may bow downward a small distance when span 28 is at its most extended point and just prior to support by pier 18 . For this reason, in an advantageous embodiment, a guiding mechanism is provided at the receiving edge of pier 18 for “lifting” the leading edge 64 . To this end, the underside 200 of leading edge 64 is sloped so that underside 200 can be used to guide span 28 upward when edge 64 reaches pier 18 . In addition, a guiding component 201 is attached to the bottom of cap 134 . Guiding component 201 extends longitudinally from the under surface of cap 134 and includes a sloped surface 202 that is effectively a mirror image of sloped surface 200 . In addition, a plurality of rollers 204 are provided on sloped surface 202 to reduce friction between surfaces 200 and 202 during reception of span 28 .
Referring now to FIGS. 5 a through 5 c, a second embodiment of the invention is illustrated. This second embodiment, like the first embodiment, includes a plurality of piers 9 , 12 , 14 , 16 and 18 and a plurality of spans 24 , 26 , 28 and 32 that traverse the distance between the piers. Each of piers 9 and 12 have a width that is generally the same width as each of the spans (e.g., 24 ). Each of piers 14 , 16 and 18 , however, has a width that is approximately twice as wide as the width of any of the spans (e.g., 28 ). To this end, pier 14 includes an in-line section 250 that is in-line with piers 9 and 12 and a lateral section 252 that is laterally positioned with respect to in-line section 250 . Similarly, pier 16 includes an in-line section 254 and a lateral section 256 while pier 18 includes an in-line section 258 and a lateral section 260 .
Referring now to FIGS. 1 a and 5 a through 5 c, as above, in order to understand the second embodiment, it is advantageous to define specific piers by specific names and specific spaces with respect to those piers by specific names. To this end, piers 12 , 14 and 18 are referred to generally as first, second and third piers, while pier 16 is referred to as an intermediate pier. In FIG. 1 a, the space between piers 12 and 14 is referred to as a first in-line space, the space 50 between piers 14 and 18 is referred to as a second in-line space, the space above first in-line space 48 is referred to as a third in-line space 52 and the space 54 above second in-line space 50 is referred to as a fourth in-line space 54 . The in-line spaces are aligned along a longitudinal axis 27 .
In addition, referring to FIGS. 1 a, 5 a and 6 , the space that is adjacent each of first in-line space 48 and lateral pier section 252 is referred to as a first lateral space 270 and the space above first lateral space 270 is referred to as a third lateral space 272 . Referring to FIGS. 1 a, 5 a and 7 , the space between lateral pier sections 252 and 260 is referred to as second lateral space 274 , the space thereabove is referred to as fourth lateral space 276 , the space between intermediate pier 256 and lateral section 260 is referred to as a fifth space and the space above the fifth space is referred to as an openable space. The lateral spaces are aligned along a lateral axis 290 .
With the piers and spaces defined above, operation of the bridge illustrated in FIGS. 5 a through 5 c can be easily understood. Referring still to FIGS. 5 a through 5 c and also to FIGS. 6 and 7, initially, to facilitate vehicular traffic over the bridge, second span 28 is in the fourth in-line space 54 (see FIG. 7 ). To open the bridge and allow water bound traffic to pass therethrough, first, span 28 is moved from the fourth in-line space 54 laterally to the fourth lateral space 276 so that span 28 is supported on the tops of lateral sections 252 , 256 and 260 of piers 14 , 16 and 18 as illustrated in FIG. 5 b. Next, span 28 is moved longitudinally along the lateral axis 290 to the left as illustrated in FIG. 5 b until a segment (i.e., the lefthand half of span 28 referred to as the “openable space” above) is positioned within third lateral space 272 as illustrated in FIG. 5 c. After this second move, an open space 300 is formed between piers 16 and 18 to allow water bound traffic to pass therethrough unobstructed.
To reclose the bridge, the process as described above is reversed. To this end, span 28 is first moved to the right as illustrated in FIG. 5 c until the entire span 28 is within fourth lateral space 276 . Then span 28 is moved laterally back into space 54 above the in-line sections of piers 14 , 16 and 18 .
The movement systems used in the second embodiment would be similar to those used in the first embodiment including motivators, roller assemblies and tracks, and should be configurable by one of ordinary still in the art. Nevertheless, it should be appreciated that while this embodiment is contemplated, in some ways, this embodiment is less preferred than the first embodiment because the movement system mechanics would be more complex. This is because the movement mechanics have to facilitate movement of span 28 in two separate directions (i.e., laterally and then longitudinally). In addition to the motivators for span movement laterally and longitudinally, this design would also likely require some other moveable components.
Referring now to FIGS. 5 a, 11 and 12 , exemplary movement assemblies at the tops of piers 14 and 18 are illustrated. Specifically, the assemblies illustrated are located at the tops of lateral pier sections 252 and 260 . Pier 14 includes timbers 450 and 452 , a pier cap 454 , several lateral roller assemblies 456 (only one illustrated), a hydraulic lift 451 for each lateral roller assembly, a span assembly 28 and at least two longitudinal roller assemblies 458 and 460 . From the first embodiment description above the functions, configurations and operation of most of the components of FIGS. 11 and 12 should be understood and therefore will not be explained again here in detail.
Hydraulic lift 451 is mounted on a top surface of cap 454 and includes an upwardly extending shaft 462 . Roller assembly 456 is mounted at the top end of shaft 462 . Lift 451 is capable of changing the vertical elevation of roller assembly 456 and other span components (e.g., 28 ) thereabove.
Referring to FIGS. 5 a, 11 , 12 and 2 , the lateral roller assemblies at the tops of in-line pier sections 250 , 254 and 258 need not include hydraulic lifts (e.g., 451 ) and therefore are more akin to the assemblies illustrated in FIG. 2 . In their highest position (i.e., with corresponding hydraulic lifts 451 extended to a maximum point), the rollers of assemblies 451 would be at the same vertical height as, and would be aligned with, the stationary roller assemblies on the in-line pier sections 250 , 254 and 258 . Thus, at their lowest position (i.e., with lifts 451 retracted), the rollers of assemblies 451 would be below the stationary rollers at a lowest level (see also FIGS. 13 and 14 ).
Referring again to FIGS. 11 and 12, longitudinal roller assembly 458 extends up from cap 454 at a lateral end of cap 454 and forms a receiving bay 470 designed to receive a lateral edge 472 of span 28 . To this end upper and lower roller banks 474 and 476 , respectively, are provided in bay 470 for supporting edge 472 . The space D 1 between roller banks 474 and 476 is slightly greater than the width D 2 of end 472 . The second longitudinal roller assembly 460 includes a single upward facing roller bank 461 on a side of hydraulic lift 451 opposite assembly 458 . Importantly, as best seen in FIG. 12, cap 454 extends longitudinally past an adjacent end 449 of span 28 on a side of lift 451 opposite pier 18 .
Referring to FIGS. 12 and 14, upward facing roller banks 461 and 476 are at the same vertical height which is slightly higher than the top of roller assemblies 451 when those assemblies 451 are in their lower positions.
Referring to FIGS. 5 a and 12 , the components at the top of lateral pier section 260 are similar to the components at the top of section 252 with a few exceptions. Similarities include a supporting timber 490 , a pier cap 482 , a hydraulic lift 492 and several (only one shown) lateral roller assemblies 494 . A first distinction is that only a single roller assembly 480 is provided at the top of pier cap 482 on the same side of lift 492 as pier 14 . Assembly 480 includes a roller bank 421 that defines an upward facing support surface 423 . The height of surface 423 is identical to the heights of surfaces 460 and 467 and is slightly higher than the tops of assemblies 494 when assemblies 494 are in their lowest positions. On the side of lift 492 opposite roller assembly 480 , span 32 rests on, and is securely mounted to, the top of pier 18 .
Referring still to FIGS. 11 and 12, span 26 forms an under surface 498 that defines downwardly extending track members 500 and 502 . Each track member 500 , 502 is shaped so as to be received and supported by roller assemblies 451 and 494 there below and thus extend laterally across span 28 . Track members 500 and 502 do not extend completely across span 28 , but rather stop short of end 472 . This is so that end 472 can be received within bay 470 .
In operation, to open the bridge, referring to FIGS. 11 through 14, with span 28 in the in-line position (see FIG. 5 a ) and lifts 451 and 492 extended, a motivator (not illustrated), drives span 28 laterally in direction 508 on roller assemblies 456 and 494 into a position supported above lateral pier sections 252 , 256 and 268 . An intermediate span position is illustrated in FIG. 11 . The motivator continues to drive span 28 until end 472 is aligned with but longitudinally displaced from bay 470 as illustrated in FIGS. 5 b and 12 . Next, lifts 451 and 492 are lowered. When lifts 451 and 492 are lowered, span 28 comes to rest and be supported on the upward facing roller bank surfaces 467 and 423 . Span 28 supported by roller assemblies 461 and 421 is illustrated in FIG. 14 . Note that lifts 451 and 492 need only be lowered a very small amount and therefore span 28 is only lowered very slightly.
Continuing, referring to FIG. 14, the second motivator (not illustrated) drives span 28 longitudinally in the direction indicated by arrow 510 . As span 28 is driven longitudinally, end 449 is received within bay 470 and is supported and restrained by roller assemblies 474 and 476 . Referring specifically to FIG. 14, roller assembly 458 should be positioned relative to assembly 480 such that span end 449 is fully received between banks 474 and 476 prior to opposite span end 447 coming off roller bank 421 . This ensures that end 447 will be supported in a cantilevered manner upon becoming unsupported.
The second motivator continues to drive span 28 in the direction of arrow 510 until span 28 is in the position illustrated in FIG. 5 c where space 300 is completely open for river bound travel.
To close space 300 and facilitate vehicular travel, span 28 is driven from its location in FIG. 5 c to the location in FIG. 5 b while being supported on longitudinal roller assemblies 458 , 460 , 480 , etc. Next, lifts 451 and 492 are extended to lift span 28 up and above longitudinal assemblies 460 and 480 and so that span 28 is supported by lateral assemblies 456 and 494 . Continuing span 28 is driven from the position in FIG. 5 b to the position in FIG. 5 a.
Importantly, when span 28 is in the in-line position (see FIG. 5 a ), span 28 is fully supported by rigid mechanical rollers as opposed to hydraulic lifts. This makes for a more resilient bridge system.
Referring now to FIGS. 8 a through 8 c, a third embodiment of the present invention will be described in the context of a bridge 330 that includes a plurality of piers 9 , 12 , 14 , 16 and 18 . In addition, bridge 330 includes spans 24 , 26 , 28 and 32 that traversing a distances between the piers, each of spans 24 , 26 and 32 traversing a distance between adjacent piers and span 28 being approximately twice as long as the other spans, traversing a distance between piers 14 , 16 and 18 .
To understand this third embodiment, as with the embodiments described above, it is helpful to specifically label several of the piers and the spaces relative thereto. To this end, piers 12 , 14 and 18 are referred to as first, second and third piers, respectively, pier 16 is referred to as an intermediate pier, the space between piers 12 and 14 is referred to as a first space 333 , the space between piers 14 and 18 is referred to as a second space, the space above the first space is referred to as a third space 336 , and the space above second space 334 is referred to as a fourth space 338 . Third space 336 is approximately the same size as span 26 and the space thereabove is referred to as a fifth space 340 .
In operation, to open a section of bridge 330 , first, with span 26 supported between piers 12 and 14 and within third space 336 , first span 26 is raised up and into fifth space 340 thereabove. After this move, the bridge is in the configuration illustrated in FIG. 8 b. Next, span 28 is moved from fourth space 338 toward third space 336 such that a segment [e.g., approximately the left half of span 28 as illustrated] of span 28 moves into third space 336 . After this move, bridge 330 is configured as illustrated in FIG. 8 c with a leading end 350 of second span 28 supported on the top of pier 16 . In this configuration, the space between and above piers 16 and 18 is completely unobstructed and water bound traffic can pass there through.
To reclose bridge 300 , the method described above is simply reversed. To this end, span 28 is moved toward span 32 until leading end 350 contacts and is supported by the top of span 18 . This configuration is illustrated FIG. 8 b. Next, span 26 is lowered until that span is supported on the tops of piers 12 and 14 as illustrated in FIG. 8 a.
Referring now to FIGS. 8 a and 9 , in order to raise and lower span 26 , the components illustrated in FIG. 9 are provided at each end at each of piers 12 and 14 . Because the components at each end of each of piers 12 and 14 are generally the same, only the components provided at one end of pier 12 are illustrated. The components at pier 12 include a timber 370 , a lower construct 374 , an upper construct 376 and a motivator 378 . Timber 370 has a lower end (not illustrated) that extends down to the bottom of the river and an upper end 380 that is received by and supports cap 372 . As above, other timbers would also be provided to support cap 372 . Cap 372 forms an upper surface 382 that is essentially flat. Motivator 378 is mounted to cap 372 in any manner known in the art. Motivator 378 is simply a lifting mechanism including a hydraulic motor of some type and a shaft 390 that extends upwardly therefrom. A distall end 392 of shaft 390 can be raised and lowered in a manner explained in more detail below.
Referring still to FIG. 9, lower structure 374 includes a concrete base member 394 and a stopper member 396 that extends downward therefrom. One or more other stopper members 396 (not illustrated) would be provided along the length of member 394 to support that member above surface 382 .
Upper structure 376 includes a plurality of eye beams 398 that form a lattice and support a deck 400 thereabove. Deck 400 forms top and bottom surfaces 402 and 404 , respectively. The lattice formed by beams 398 contact under surface 404 . In addition, distall end 392 of shaft 390 contacts under surface 404 . Surface 402 provides a driving deck for vehicular traffic.
Referring now to FIGS. 9 and 10, the components of FIG. 9 are shown in FIG. 10 in a raised position where shaft 390 has been extended to raise both the upper and lower structures 376 and 374 , respectively. Once raised, a space 410 is provided between span 26 and surface 382 . Referring also to FIG. 8 b and FIG. 8 c, once span 26 is raised as illustrated in FIG. 10, span 28 is rolled into space 410 . The support rolling structure used to roll span 28 is similar to the structure illustrated in FIG. 3 .
It should be understood that the methods and apparatuses described above are only exemplary and do not limit the scope of the invention, and that various modifications could be made by those skilled in the art that would fall under the scope of the invention. For example, while the embodiments above include roller assemblies mounted to the tops of piers, other embodiments may include roller assemblies mounted to the undersides of spans. In addition, referring to FIGS. 8 a - 8 c, instead of moving span 26 upward, span 26 may be lowered to provide a space for span 28 . Moreover, referring to FIGS. 5 a - 5 c and 11 through 14 , while that embodiment shows span 28 being vertically repositioned between lateral and longitudinal moves, in other embodiments rollers may be raised and lowered so that the vertical span position remains essentially constant. Furthermore, while two motivators are described above, it should be appreciated that some embodiments may require only a single motivator. In addition, embodiments with additional vertical restraints are contemplated.
To apprise the public of the scope of this invention, the following claims are made:
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An apparatus for opening a mechanical bridge. The apparatus includes at least two adjacent bridge spans where the first of the bridge spans is removable from its initial position and the second of the bridge spans is at least partially movable into the space originally occupied by the first span so that at least a portion of the second bridge span can be separated from yet a third adjacent span. This forms an opening between the second and third spans. Alternatively, a span can be moved laterally and then longitudinally to open a section of the bridge.
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TECHNICAL FIELD OF THE INVENTION
The present invention generally relates to a rasterizer for use in computer graphics display systems and, more particularly, to a rasterizer comprising a converging data pipeline device having a resending mechanism and a shared pipeline data path for reducing the amount of pipe stages needed in the rasterizer to accommodate two converging pipeline data paths.
BACKGROUND OF THE INVENTION
Computer graphics display systems are commonly used for displaying graphical representations of objects on a two-dimensional video display screen. Current computer graphics display systems provide highly detailed representations and are used in a variety of applications. A computer graphics display system generally comprises a central processing unit (CPU), system memory, a graphics machine and a video display screen.
In typical computer graphics display systems, an object to be presented on the display screen is broken down into graphics primitives. Primitives are basic components of a graphics display and may include points, lines, vectors and polygons (e.g., triangles and quadrilaterals). Typically, a hardware/software scheme is implemented to render, or draw, the graphics primitives that represent a view of one or more objects being represented on the display screen.
Generally, the primitives of the object to be rendered are defined by the host CPU in terms of primitive data. For example, when the primitive is a triangle, the host computer defines the primitive in terms of the X, Y and Z coordinates of each of its three vertices, the normals of each of the vertices, N x , N y and N z , and the red, green, blue and alpha (R, G, B and α) color values of each vertex. Alpha is a transparency value. Rendering hardware interpolates all of this data to compute the display screen pixels that represent each primitive, and the R, G, B and α values for each pixel.
Additionally, the primitives may also be defined in terms of texture by using texture mapping when rendering images. Texture mapping allows different parts of an object being rendered to have different appearances, such as when it is necessary or desirable to render an object which is comprised of several composite features, such as a brick wall comprised of several bricks. Rather than drawing each brick individually, a wall can be drawn and then a brick wall texture can be mapped onto the wall.
Texture coordinates are normally referred to as s, t, r and q coordinates. In order to draw a texture-mapped scene, both the object coordinates and the texture coordinates for each vertex must be implemented. The object coordinates define the location of the vertex on the screen and the texture coordinates determine which texel in the texture map is to be assigned to that particular vertex.
A typical graphics machine includes a geometry accelerator, a rasterizer, a frame buffer controller and a frame buffer. Texture mapping is accomplished in the rasterizer, which performs pixel rasterization and texel rasterization to render a texture-mapped image on the display. The geometry accelerator receives three-dimensional vertex data from the host CPU in terms of red, green, blue and alpha (R, G, B and α) data, X, Y, and Z data, N x , N y and N z data, and s, t, r and q coordinate data for each primitive received by the geometry accelerator. The X, Y and Z coordinates define the locations of the vertices of the primitives on the display screen whereas the N x , N y and N z data define the directions of the normals of the vertices of the primitives. The geometry accelerator processes all this data and outputs new R, G and B data and s, t, r and q data for each vertex to the rasterizer. When the image to be rendered is two-dimensional, the information defining the image can be sent directly to the rasterizer without first being sent to the geometry accelerator. Once the rasterizer receives the R, G, B data and the s, t, r and q data for the vertices, the rasterizer performs texture mapping and rasterizes the texture-mapped image.
Rasterizers capable of performing texture mapping generally comprise a texel rasterizing component and a pixel rasterizing component. These two components operate in parallel and are synchronized such that, as the pixel rasterizing component determines the location of a pixel on the screen, the texel rasterizing component determines the texture to be assigned to the particular pixel and outputs it to the pixel rasterizing component which maps it onto the particular pixel. For example, as the pixel rasterizing component determines the location of a pixel on the screen corresponding to a corner of a floor being rendered, the texel rasterizing component may determine the texture of a carpet to be mapped onto the pixel.
Within the texel rasterizing component, texture information and commands are received from the host CPU and processed to generate a texel which is output to the pixel rasterizing component. Generally, components referred to as an edge stepper and a span stepper within the texel rasterizer determine the s, t, r and q coordinates of each texel to be mapped and output this information to a rational linear interpolator, which applies a correction to the texel values to obtain a perspective view. This information is then output to a tiler which performs mathematical calculations on the texture information sent by the host CPU to the texel rasterizer to generate virtual addresses. These virtual addresses are then output to a directory which references them to memory to produce memory addresses corresponding to the locations in memory where the texture data corresponding to the texture to be mapped is stored. This information is then output to the pixel rasterizing component which maps the textures onto the pixels.
In order to maximize the speed of the rasterizing process, it is known to utilize cache-based rasterizers which store the texture information in cache memory to enable the rasterizer to quickly access the texture information. However, this requires checking the cache to determine whether the texture information sought is held in cache. When the texture information sought is not held in cache, the processing of the information by the components of the texel rasterizer, such as the tiler and the rational linear interpolator, must be halted long enough for the texture information sought to be downloaded by the host CPU into cache. The information being processed by the texel rasterizer travels along a "buffered path" while the information being downloaded into cache travels along an "unbuffered path". In order to prevent the information traveling along the unbuffered path from overwriting, and thus corrupting, the data traveling along the buffered path, separate paths have been used. By using separate paths, the information being sent along the buffered path is halted and the information being downloaded into cache by the CPU is simply sent down the unbuffered path and loaded into cache, without the possibility of overwriting the data traveling along the buffered path. Once the information has been loaded into cache, the shifting and processing of the data along the buffered path is resumed.
One disadvantage of providing completely separate paths for the buffered information and for the information being downloaded into cache is that each of these paths requires a large number of pipe stages for each path which, in turn, requires the allocation of a large amount of space for each path.
Accordingly, a need exists for a method and apparatus which maximizes the processing speed and efficiency of a cache-based texel rasterizer of a computer graphics display system while minimizing the amount of space required to be allocated for the buffered and unbuffered paths of the texel rasterizer component.
SUMMARY OF THE INVENTION
The present invention provides a converging data pipeline device comprising a first pipeline data path for carrying data, a second pipeline data path for carrying data, a shared pipeline data path which is capable of receiving data from each of the first and second paths, and a resending mechanism comprised by the second path. The resending mechanism makes a backup copy of at least a portion of the data passing through a particular location on the second path. Each of the paths comprises a plurality of pipeline stages, each pipeline stage capable of holding data and propagating the data in a direction from a first end of the path toward a second end of the path. The first end of the shared path is in communication with the second ends of the first and second data paths for receiving data from the second ends of the first and second data paths. When the flow of data is suspended along the second path, data is sent down the first path and through the shared path. This data will overwrite the data from the second pipeline data path which was on the shared path when the flow of data was suspended. A backup copy of the overwritten data is stored in the resending mechanism. When the flow of data on the second pipeline data path is resumed, the backup copy stored in the resending mechanism is sent through the second pipeline data path and through the shared pipeline data path so that the data which was overwritten is replaced.
In accordance with the preferred embodiment of the present invention, the converging data pipeline device is implemented in a cache-based texel rasterizer of a computer graphics display system. In this embodiment, the second pipeline data path corresponds to the buffered, or rendering, path within the texel rasterizer and the first pipeline data path corresponds to the unbuffered path within the texel rasterizer. Texture information is stored in a cache memory device of the texel rasterizer. The cache memory device is in communication with the second end of the shared pipeline data path for receiving data sent to cache via the shared pipeline data path. The first and second pipeline data paths are at least partially contained within a tiler component of the texel rasterizer and the shared path is contained partially within the tiler component and partially within a directory component of the texel rasterizer. As the texture coordinates flow along the second pipeline data path, the data resending mechanism, which is a resettable storage means, makes a backup copy of the texture coordinates before sending the texture coordinates to the shared pipeline data path.
The tiler component translates the texture coordinates into virtual address information and outputs the virtual address information to the directory component of the texel rasterizer via the shared path. The directory component then references the virtual address information to the cache memory device. The directory component determines whether a reference exists for the virtual address information. If the directory component determines that the reference does not exist, the processing and shifting of data along the second pipeline data path is suspended while the missing block of texture information is sent along the first pipeline data path to the shared pipeline data path and into the corresponding addresses in the cache memory device. When this occurs, the data which was contained on the shared pipeline data path which came from the second pipeline data path is overwritten. The resending mechanism makes a backup copy of the overwritten data as it passes through the second pipeline data path onto the shared pipeline data path. Once the texture information has been downloaded into the cache memory device, the resending mechanism sends at least a portion of the data stored therein to the shared path to replace the data which was overwritten. The data flow along the second pipeline data path is then resumed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a functional block diagram of a well known computer graphics display system;
FIG. 2 illustrates a functional block diagram of a rasterizer of the computer graphics display system shown in FIG. 1;
FIG. 3 illustrates a functional block diagram of a texel rasterizing component of the rasterizer shown in FIG. 2;
FIG. 4 illustrates a functional block diagram of the tiler of the texel rasterizing component shown in FIG. 3, wherein the tiler comprises the resending mechanism of the present invention; and
FIG. 5 illustrates timing diagrams functionally demonstrating the operation of the resending mechanism shown in FIG. 4.
DETAILED DESCRIPTION OF THE INVENTION
The basic components of a conventional computer graphics display system are shown in FIG. 1. The computer graphics display system 11 comprises a CPU 12, system memory 14, a display device 21, a geometry accelerator 16, a rasterizer 24 and an I/O interface 25, which connects the geometry accelerator 16 and rasterizer 24 with the host CPU 12. The CPU 12 communicates with the geometry accelerator 16, the rasterizer 24 and system memory 14 via I/O bus 18. The I/O interface 25 is connected to the rasterizer 24 and to geometry accelerator 16 via I/O lines 22 and 23, respectively. When the data output to the graphics hardware is 2-D data, it is sent directly to the rasterizer 24. When the data output to the graphics hardware is 3-D data, it is sent to the geometry accelerator 16 and then to the rasterizer 24. The data is sent from the geometry accelerator 16 to the rasterizer 24 via bus 26. A user 19 communicates with the CPU 12 via a peripheral device, such as a keyboard or mouse, to indirectly control the data being sent to the geometry accelerator 16, thereby controlling the rendering of the image being displayed on the display device 21.
FIG. 2 illustrates a block diagram of the rasterizer 24 shown in FIG. 1. Rasterizer 24 is comprised of a texel rasterizer 30 and a pixel rasterizer 31. The output of the texel rasterizer 30 is input to the pixel rasterizer 31 via line 33. The output of the pixel rasterizer is connected to display 21. When the information being sent to the rasterizer 24 is 2-D information, the information is sent via bus 26 to both the texel rasterizer 30 and to the pixel rasterizer 31. When the information being sent to the rasterizer 24 is 3-D information, the information is sent first to the geometry accelerator 16 and then from the geometry accelerator 16 via bus 26 to both the texel rasterizer 30 and to the pixel rasterizer 31. The operations of the pixel rasterizer 31 are well known in the art and, therefore, will not be discussed here in the interest of brevity.
The components of the texel rasterizer 30 of the present invention will now be discussed in detail with reference to FIG. 3. The texel rasterizer 30 preferably is implemented in an application specific integrated circuit (ASIC). The bus interface 38 receives commands and data being sent to the texel rasterizer 30 on bus 26 and stores the data and commands to be processed by texel rasterizer 30 in front end storage device 39. Front end storage device 39 is comprised of a buffered write first-in-first-out (FIFO) memory device (not shown), a buffered read FIFO memory device (not shown), an unbuffered write FIFO memory device (not shown) and an unbuffered read FIFO memory device (not shown). The buffered write and read FIFOs are comprised as part of the buffered path 50 of the texel rasterizer 30 and the unbuffered read and write FIFOs are comprised as part of the unbuffered path 52 of the texel rasterizer 30. The purposes of the buffered and unbuffered paths are discussed below in detail. The buffered and unbuffered write FIFOs store information written to the front end storage 39 by the bus interface 38. The buffered and unbuffered read FIFOs store information to be read by the bus interface 38 and processed by the bus interface 38 and output onto bus 26.
The front end storage device 39 receives information from the bus interface 38, decodes the information and decides where to send the information, i.e., it decides whether to send it to the buffered write FIFO or the unbuffered write FIFO. If the information is written to the buffered write FIFO, the front end storage device 39 outputs the information along the buffered path 50 to edge stepper 40. The edge stepper 40 performs rasterization to determine the s, t, r and q coordinates for each texel in the vertical direction of the primitive received by the edge stepper 40. The span stepper 41 performs rasterization to determine the s, t, r and q coordinates for each texel in the horizontal direction of the primitive. Once the s, t, r and q coordinates for each texel of the primitive have been determined, the rational linear interpolator 42 determines the perspective view for the primitive and applies a correction value to the coordinates. The corrected coordinates are then provided to the tiler 43 which performs a mathematical algorithm with the corrected coordinates to translate the coordinates into a virtual memory address.
The directory 44 receives the virtual memory address and references it to the cache memory 45 to determine whether the texture mapping information sought is located in cache memory 45. If a reference is not available, a "miss" has occurred and the directory 44 outputs an acknowledge signal 66 onto control line 53 which causes the flow and processing along the buffered path 50 to be suspended. At this point, whatever the last state was when the ackowledge signal occurred is held at each stage of the buffered path 50. After the acknowledge signal 66 occurs (see FIG. 5), a halt signal 65 is generated by the directory 44 and output onto control line 46, which switches the flow of data from the buffered path 50 to the unbuffered path 52 in the tiler 43. A validity signal 67 may also be generated by the tiler 43 and output to the directory 44 on control line 47. The purposes of the ackowledge signal, the halt signal and the validity signal are discussed in detail below with respect to FIG. 5.
When the acknowledge signal occurs, the directory 44 informs the texture mapping daemon (not shown) via an external interrupt line (not shown) that the texture mapping information sought is not in the cache memory device 45. As a result, the texture daemon downloads the missing block into cache 45 via the unbuffered path 52. The unbuffered texture objects are communicated to the texel rasterizer 30 via bus 26. The front end storage device 39 then causes the texture mapping information to be sent over bus 52 to tiler 43 and through directory 44, which in turn sends the information into cache memory device 45.
Bus 52 comprises the unbuffered path. The buffered path 50 cannot be used for downloading the texture mapping information into cache memory 45 because doing so would cause all of the information on the buffered path 50 to be overwritten. The buffered path 50 and the unbuffered path 52 both pass through the tiler 43 and converge into a shared path which passes through the tiler 43 and through the directory 44. The reason for the unbuffered path passing through the tiler 43 and the directory 44 is that the texture mapping information being downloaded to cache memory device 45 must be translated by the tiler 43 to obtain the virtual addresses and then the directory 44 must reference it to the cache memory device 45 where the texture mapping information being downloaded is to be stored.
In known cache memory-based rasterizers, there is no danger of the information on the buffered path being overwritten by the information sent along the unbuffered path because the two paths remain separate. The buffered path passes through the tiler and the directory whereas the unbuffered path bypasses the tiler and the directory and interfaces directly with the cache. The translation and referencing of the texture information sent down the unbuffered path to the cache is performed by software in the host CPU. It is desireable to remove this processing task from the host CPU to the texel rasterizer by providing two separate paths through the tiler and the directory to allow the information on the unbuffered path to be translated and referenced by the tiler and the directory, respectively. However, providing two separate paths through the tiler and the directory results in a trade off in terms of the amount of space utilized in the texel rasterizer 30 to accommodate the two paths. In order for the tiler 43 to perform translations of the s, t and r coordinates into virtual addresses, several pipe stages and logic circuits are implemented within the tiler 43. The various types of logic circuits (not shown) required are provided in between the pipe stages. In general, each path may require eight pipe stages, each stage being 300 bits wide on average. The number of bits increases as the data is shifted through the tiler 43 toward the directory due to the operations being performed on the data by the logic circuits. Therefore, the amount of space needed to be allocated for the separate paths is substantial.
In accordance with the present invention, it has been determined that a portion of the buffered path 50 passing through the tiler 43 can be replaced by a resending mechanism which makes a backup copy of a portion of the data passing through a particular location along the buffered path 50 and that the buffered and unbuffered paths can be merged to form a shared path. By using the resending mechanism of the present invention in conjunction with the shared path, a significant amount of space is saved within the texel rasterizer 30. The resending mechanism, which is a resettable storage means, is more space-efficient than equivalent number of bits of pipeline registers. No selection of data from different paths is necessary at processing elements along the shared path. Another advantage of using the resending mechanism and the shared path is that, if expansion occurs along the second or the shared path, the resending mechanism can be located at a point that minimizes the number of bits needed to recreate the second path portion that has been overwritten.
FIG. 4 is a functional block diagram of the tiler 43 shown in FIG. 3. As illustrated, the tiler 43 contains a resending mechanism 55 located at the top of the tiler 43 which receives data being shifted along the buffered path 50 from the rational linear interpolator (RLI) 42. The resending mechanism 55 is a resettable storage means which preferably functions in a manner similar to a FIFO memory device. Preferably, the resettable storage means is ninety bits wide and twelve words deep. However, it will be apparent to those skilled in the art that the present invention is not limited with respect to the manner in which the resending mechanism 55 is physically implemented or with respect to the size of the resending mechanism 55. The arrow in FIG. 4 pointing down and away from the dashed box representing tiler 43 indicates that the directory 44 is below the tiler 43. It can be seen from FIG. 4 that the buffered path 50 and the unbuffered path 52 converge at point 59 within the tiler 43 to form a shared path 60. Each of the dashes 57 represents a pipe stage. For ease of illustration, the logic circuits at the inputs and outputs of the pipe stages 57 have not been shown.
The pipe stage 61 located within the directory 44 represents the location at which the directory 44 determines that a miss has occurred. It will be apparent to those skilled in the art that the present invention is not limited with respect to the location within the directory 44 at which a miss is detected or with respect to the location at which the paths converge to form the shared path. Once a miss has been detected, the directory 44 causes the buffered path to be halted and notifies the texture daemon (not shown) that the data being sought is not located in cache memory device 45. The daemon then causes the s, t and r coordinates corresponding to the missing texture mapping information to be sent down unbuffered path 52 to the tiler 43. The unbuffered data is then shifted through the pipe stages 57 and operated on by the logic circuits (not shown). When the halt signal 65 occurs, information from the buffered path will be contained on the shared path 60. This information will be overwritten and corrupted when the data on unbuffered path 52 is shifted along the shared path 60 through tiler 43 and directory 44. Therefore, once the unbuffered data has been shifted through directory 44 into cache memory 45, resending mechanism 55 will resend the buffered command data which was contained on the shared path 60 when the halt signal 65 occurred. Once the information which was missing from cache memory device 45 has been placed in cache memory device 45, the resent command data being shifted along the shared path 60 into the directory 44 will cause the corresponding texture mapping information to be output from cache memory device 45 and sent to the pixel rasterizer 33 (See FIG. 3).
FIG. 5 is a timing diagram illustrating the timing of the signals at the tiler 43/directory 44 interface which trigger a halt and which control the sending of the unbuffered data and the resending of the buffered data. As shown in FIG. 5, when a miss is detected, an acknowledge signal 66 sent from the directory to the tiler goes low causing the information along the buffered path to back up. This is followed by a halt signal 65 provided from the directory 44 to the tiler 43 which goes high. This switches the flow of data going through the tiler 43 and the directory 44 from the buffered path 50 to the unbuffered path 52. The acknowledge signal causes the components of the texel rasterizer 30 to suspend processing of information along the buffered path 50 and to hold the last state present at each stage along the buffered path 50 when the acknowledge signal 66 went low. When the halt signal 65 goes high, the acknowledge signal 66 will return to the high state. Now, however, the flow of data going into the directory 44 comes from the unbuffered path 52. The logical AND (not shown) of a validity signal 67 sent from the tiler 43 to the directory 44 and acknowledge signal 66 from the directory 44 to the tiler 43 is used as an indicator of how many buffered commands got flushed from the shared path 60 when the unbuffered commands were sent down the unbuffered path 52 onto the shared path 60 and through the directory 44. When the halt signal 65 returns to the low state, the flow of the data into the directory 44 switches back to the buffered path 50. This switching is accomplished by a multiplexer (not shown) located within tiler 43 which is responsive to the halt signal 65. The tiler 43 will then direct the resending mechanism 55 to resend all of the buffered commands which were on the shared path 60 when the halt signal was asserted.
In accordance with the preferred embodiment of the present invention, the shared path 60 comprises eight pipe stages, each of which can hold one buffered or unbuffered command. Of these eight, three are in the directory 44 and five are in the tiler 43. In accordance with this embodiment, the resending mechanism 55 makes a backup copy of the eight buffered commands which will be held on the shared path 60 when the halt signal 65 is asserted. Normally, all eight of these commands will be resent by the resending mechanism 55. However, when the validity signal 67 goes low or the acknowledge signal 66 goes low while a buffered command is on the shared path, the tiler 43 is informed that less than eight commands have been flushed and that the resending mechanism 55 will only resend the commands which were flushed. The number of states that the validity signal 67 is low or that the acknowledge signal 66 is low will determine how many and which commands will need to be resent. For example, when the validity signal 67 is deasserted for one clock pulse 68 after the buffered command which caused the miss has crossed the tiler 43/directory 44 interface, this indicates that only seven valid commands were flushed and that only those seven need to be resent. Similarly, if the validity signal 67 is deasserted for two clock pulses 68 after the buffered command which caused the miss has crossed the tiler 43/directory 44 interface, this is an indication that only six valid commands were flushed and that only those six will need to be resent. Therefore, the resending mechanism is a "smart" resending mechanism in that it only resends those commands that need to be resent.
The "Bs" above the clock pulses 68 in FIG. 5 correspond to buffered data at the tiler 43/directory interface 44 whereas the "Us" correspond to unbuffered data. The numerals above the "Bs" indicate the buffered command number along the shared path 60. Since the validity signal 67 was deasserted for two clock pulses after buffered command 1 crossed the tiler 43/directory 44 interface, this indicates that buffered commands 2 and 5 are not going to be resent. Therefore, after the unbuffered commands are sent, buffered commands 1, 3, 4, 6, 7 and 8 will be resent by resending mechanism 55. For ease of illustration, only resent buffered commands 1 and 3 are shown in FIG. 5.
It should be noted that the present invention is not limited with respect to the number of commands stored in the resending mechanism 55 and/or resent by the resending mechanism 55. It will be apparent to those skilled in the art that the resending mechanism 55 and the shared path 60 can be designed and implemented in a variety of different ways to achieve the goals of the present invention. It should also be noted that the present invention is not limited with respect to the location of the resending mechanism or with respect to the location of the shared path, provided they are located in such a manner as to be consistent with the goals of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the manner discussed above for switching the data flow from the buffered path to the unbuffered path, and vice versa, and for determining which data stored in the resending mechanism needs to be resent. Persons skilled in the art will realize that the manner discussed above is only one of many ways of performing these tasks. It will be apparent to those skilled in the art that other modifications may be made to the embodiments discussed above without deviating from the spirit and scope of the present invention.
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The present invention provides a converging data pipeline device comprising a first pipeline data path for carrying data, a second pipeline data path for carrying data, a shared pipeline data path which is capable of receiving data from each of the first and second pipeline data paths, and a resending mechanism comprised by the second pipeline data path. The resending mechanism makes a backup copy of at least a portion of the data at a particular location on the second path. Each of the paths comprises a plurality of pipeline stages, each pipeline stage capable of holding data and propagating the data in a direction from a first end of the path toward a second end of the path. The first end of the shared path is in communication with the second ends of the first and second data paths for receiving data from the second ends of the first and second data paths. When the flow of data is suspended along the second path, data is sent down the first path and through the shared path. This data will overwrite the data from the second path which was on the shared path when the flow of data on the second path was suspended. A backup copy of the overwritten data is stored in the resending mechanism. When the flow of data on the second path is resumed, the backup copy stored in the resending mechanism is sent through the second path and through the shared path so that the data which was overwritten is replaced. In accordance with the preferred embodiment of the present invention, the converging data pipeline device is implemented in a cache-based texel rasterizer of a computer graphics display system.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method and apparatus for recording images and, more particularly, to such image recording method and apparatus which enable recording of an image on sheet material in such manner as to protect the recorded images against the degradation of image quality by dirt, for example.
2. Description of the Prior Art
In the art, various recording methods have been proposed to record images on sheet material. Among them, a thermal recording method has been widely admitted to be advantageous in respect of reliability and operability. Japanese Patent Application laid open Nos. 161946/1979 and 82676/1980 have disclosed a recording apparatus based on the principle of the thermal transfer recording method. With the recording apparatus, a common uncoated paper can be used as the recording medium. Furthermore, there are obtained recorded images having improved resolution. In this known apparatus, an image is recorded through two transfer steps, an intermediate transfer step and a final transfer step. At the intermediate transfer step, the surface of an intermediate transfer film is brought into contact with a portion of the solid ink layer of a transfer master. While keeping the contact, the ink layer is selectively heated by means of a heating element from the backside of the film so as to transfer an ink image onto the film. At the final transfer step, the ink image is transferred onto a sheet of common paper from the film.
Since the ink is heated through an intermediate transfer film, the amount of ink transferred onto the film is maintained nearly constant even when the solid ink layer on the transfer master has some irregularity in layer thickness. Therefore, there are obtained images of high resolution. This is an important advantage of the thermal transfer recording system mentioned above. Another advantage of the recording system is that as the recording medium there may be used not only any common papers but also any other media optionally selected.
The above image recording process comprising the steps of forming an image on an intermediate transfer film at first and then transferring the image onto a recording paper from the film may be applied to various recording systems other than the above described thermal recording system by suitably modifying the method of forming images on the intermediate transfer film.
However, in any case, the known image recording method involves some problems. Firstly, a periodical exchange of the intermediate transfer film is required because it is worn and damaged in use. Time and labour consumed for such maintenance work are by no means small. Secondly, it is difficult to increase the efficiency of image transfer from the intermediate transfer to the final recording material. There has not yet been proposed any effective solution to this problem.
The thermal recording method is a good method also for recording multi-color images or natural color images on sheet material. However, when sharp and clear color images are desired, the method according to the prior art is not satisfactory.
SUMMARY OF THE INVENTION
Accordingly it is the primary object of the invention to provide an image recording method and apparatus which eliminates the problem of low transfer efficiency caused by the presence of an intermediate transfer film.
It is another object of the invention to provide an image recording method and apparatus which provides images of improved durability recorded on sheet material.
To attain the above objects according to the invention there is provided a recording method comprising the steps of forming an image on one surface of a film and and binding the film itself to a base sheet on the side of the surface on which the image has been formed. In the record obtained according to the method of the invention, the recorded image is present in the state sandwiched in between the base sheet and the film. The image former is never exposed to the air. The durability and weather resistance of the recorded image are remarkably improved. The film having the image former adhered thereto constitutes a part of the final record. Therefore, maintenance of the film is no longer necessary.
It is a further object of the invention to provide a recording method and apparatus which permits recording of multi-color or natural color images with high sharpness and with the advantage of easy handling while employing the thermal recording process.
To attain the objects accroding to one embodiment of the invention, there is provided a recording method comprising the steps of selectively applying heat to individual heat sensitive color forming sheets each comprising a supporting sheet and a transparent color forming layer on the supporting sheet, which color forming layer is adhesive and develops a color under the action of heat but the colors developed in the individual layers being different from each other, thereby forming monochromic images in different colors on the individual color forming sheets; and separating each color forming layer with the formed monochromic image from the corresponding supporting sheet and laying the separated individual layers on a common base sheet successively in layers making use of their own adhesiveness.
Other and further objects, features and advantages of the invention will appear more fully from the following description of preferred embodiments taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view showing a first embodiment of the invention;
FIGS. 2 and 3 show modifications of the first embodiment respectively;
FIG. 4 shows a second embodiment of the invention;
FIG. 5 shows a modification of the second embodiment;
FIG. 6 is a perspective view of a heat sensitive color forming sheet used in the third embodiment of the invention;
FIG. 7 is a cross-sectional view thereof showing the structure of the sheet in detail;
FIG. 8 is a similar cross-sectional view showing a modification of the heat sensitive color forming sheet; and
FIG. 9 is a schematic view showing a third embodiment of the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 1 showing the first embodiment of the invention, 1 is an ink ribbon composed of a plastic film in the form of web and a solid ink layer coated on the film. The ink ribbon 1 is supplied from a ribbon supply drum 2 and taken up by a take-up drum 4 after passing about a roller 3. The ink ribbon 1 passes around the roller 3 with the ink coated surface outward.
Supplied from a film supply drum 5 is a transparent plastic film 6 which is in the form of a very thin web. At the position of the roller 3, the plastic film 6 comes into contact with the ink coated surface of the ink ribbon 1. A preferred example of the film 6 is a film of polyethyleneterephthalate about 10 μm thick.
7 is a thermal head disposed opposed to the roller 3 through the ink ribbon 1 and the film 6 therebetween. The ink ribbon 1, the supply and take-up rollers 2 and 4, the roller 3 and the thermal head 7 constitute together a recording part of the apparatus.
8 is a base sheet supply drum from which a base sheet 9 is supplied. The base sheet 9 is a white and opaque paper or plastic sheet in the form of web. At the position of a roller 10, the base sheet 9 is laid on the film 6 and then it passes between a pair of pressing rollers 11 and 12. The paired pressing rollers 11, 12 contain a heat source therein. A pair of cutters 13 and 14 are disposed behind the pressing rollers 11 and 12 respectively.
The film 6 is fed from the supply drum 5 at a constant speed and is selectively heated by the thermal head 7 while running in contact with the ink coated surface of the ink ribbon 1. The heat from the thermal head 7 is applied to the ink layer on the ribbon 1 through the film 6. An amount of ink corresponding to the heat applied from the thermal head is melted thereby and the melted ink adheres to the surface of the film 6. In this manner, an ink image as indicated by 15 is formed on the film 6. The density of the ink image may be controlled by controlling the amount of heat generated from the thermal head, thereby controlling the amount of ink to be adhered to the film 6. The control of the amount of heat from the thermal head 7 is attained by controlling the driving current to the head. Therefore, it is possible to form the ink image as a halftone image by suitably controlling the level of the driving current to the thermal head.
The running of the film 6 may be intermittent at least in the area of the thermal head 7 while applying to the thermal head a pulsating driving current in synchronism with the intermittent running of the film. In this case also it is possible to obtain a halftone ink image by suitably changing the pulse width of the above pulsating driving current, namely changing the pulse duty, thereby controlling the amount of heat from the thermal head 7.
The film 6 having the ink image 15 formed thereon comes to the position of the roller 10 where the image bearing surface of the film 6 is overlaid with the base sheet 9. The film 6 and the base sheet 9 together pass between the heated pressing rollers 11 and 12 by which the film 6 is bonded to the base sheet 9 in the manner of heat and pressure bonding. To perform the bonding more easily and surely it is advisable that a plastic coating layer be previously applied to the surface of the base sheet 9. To carry out the bonding there may also be used other methods than the shown heat and pressure bonding. For example, any suitable adhesives or binders may be used.
The base sheet 9 and the film 6 thus bonded together are cut by the cutters 13 and 14 to obtain a desired hard copy. The hard copy thus obtained has a sufficient strength and stiffness for handling because of its base sheet 9. In the hard copy, the ink image is between the film 6 and the base sheet 9 and not exposed to the air. Therefore, the image is protected against dirt and other deteriorating matters. It has excellent durability and weather resistance.
FIG. 2 shows a modification of the above first embodiment.
In this modification, the film 6 and the ink ribbon 1 are previously laid one on the other and in the overlapped state they are wound around the supply drum 5. The overlapped film and ink ribbon are fed together from the supply drum 5 and pass between the roller 3 and the thermal head 7 where an ink image is formed in the same manner as the above. After the ink image has been formed on the film 6, the ink ribbon 1 is separated from the film at the position of a roller 16. The separated ink ribbon 1 is taken up around the take-up drum 4. Other parts of the modification correspond to those of the above first embodiment and need not be further described.
FIG. 3 shows another modification of the first embodiment.
In this embodiment, the thermal recording part 1, 2, 3, 4, 7 is replaced by an electrostatic recording part. The electrostatic recording part is constituted of an electrostatic recording head 70, a hopper 71 and a toner supply drum 72. Other parts of the apparatus correspond to those of the first embodiment shown in FIG. 1. The electrostatic head 70 applies to the film 6 electric charges to form a latent image thereon. Toner is fed to the toner supply drum 72 from the hopper 71. The toner is charged with the opposite polarity to that of the latent image. The toner applied onto the film 6 by the toner supply drum 72 adheres to the latent image to develop it. The film 6 having the toner image 15' thereon is overlaid with the base sheet 9. Then, the film 6 and the base sheet 9 are bonded together by the pressing rollers 11 and 12. Since the toner image 15' is sandwiched in between the base sheet 9 and the film 6, the process for fixing the image is dispensable. Of course it is possible to carry out the fixing treatment directly after the development. It is also possible to suitably select the temperature condition for the heat and pressure bonding in such a manner as to carry out the fixing treatment simultaneously with the bonding.
In the above first embodiment and its modifications, there have been obtained monochromic records. In the second embodiment described hereinafter there are obtained polychromic records.
In FIG. 4 showing the second embodiment, a film 6 as described above is supplied from a film supply drum 5. Along the running path of the film 6 there are arranged three different color recording parts, a cyan recording part, a magenta recording part and a yellow recording part at predetermined intervals.
The cyan recording part is constituted of an ink ribbon 1A coated with cyan ink, supply and take-up drums 2A and 4A, roller 3A and thermal head 7A. Similarly, the magenta recording part is constituted of an ink ribbon 1B coated with magenta ink, supply and take-up drums 2B and 4B, roller 3B and thermal head 7B, and the yellow recording part is constituted of an ink ribbon 1C coated with yellow ink, supply and take-up drums 2C and 4C, roller 3C and thermal head 7C. The thermal heads 7A, 7B and 7C are driven in synchronized relation with each other so as to make the cyan, magenta and yellow inks superimposed each other for the same image.
Other parts of the apparatus correspond to those of the apparatus shown in FIG. 1. According to the second embodiment, cyan ink image, magenta ink image and yellow ink image are superimposed each other to form a full color image. In this manner, any desired polychromic records can be obtained with the same advantages as described above.
FIG. 5 shows a modification of the second embodiment.
In this modification, a film for cyan 6A is fed from a film supply drum 5A, a film for magenta 6B is fed from a film supply drum 5B and a film for yellow 6C is fed from a film supply drum 5C. A cyan ink image 15A is formed on the film 6A by a cyan recording part 1A, 2A, 3A, 4A, 7A similar to that in FIG. 4. Similarly, a magenta ink image 15B is formed on the film 6B by a magenta recording part 1B, 2B, 3B, 4B, 7B and a yellow ink image 15C is formed on the film 6C by a yellow recording part 1C, 2C, 3C, 4C, 7C.
The films for magenta and yellow 6B and 6C are guided to a roller 19, passing about rollers 17 and 18 respectively. At the position of the roller 19, the film for cyan 6A is laid on the film for magenta 6B and the latter is on the film yellow 6C. Thus, the three film layers are superimposed. Further, a base sheet 9 is laid on the image side surface of the top film layer 6A. The superimposed four layers 6A, 6B, 6C and 9 together are pressed and heated by a pair of pressing rollers 11 and 12 containing a heat source. Thus, the superimposed four layers are bonded together.
The registration of cyan ink image, magenta ink image and yellow ink image for the same image may be attained in the following manners:
If the length of the film 6A extending from the thermal head 7A to the roller 19, the length of the film 6B from the thermal head 7B to the roller 19 and the length of the film 6C from the thermal head 7C to the roller 19 are all the same, then the registration can be attained by driving the three thermal heads 7A, 7B, 7C at the same time for the same image.
If the three films 6A, 6B, 6C are different from each other in the above length between thermal head and roller 19 as in the case shown in FIG. 5, the registration may be attained by suitably shifting the driving timing of the thermal heads 7A, 7B, 7C from each other according to the difference in the above length among the three films 6A, 6B, 6C.
In the above embodiment wherein the three films 6A, 6B, 6C are superimposed, if the laminated web comprising the three layers 6A, 6B, 6C has already a sufficient strength for handling of a hard copy, then the base sheet 9 may be omitted. However, in this case, the cyan ink image 15A on the film 6A will be exposed to the air. In order to avoid it, some change of the arrangement shown in FIG. 5 is needed. The positional relation between the cyan ink ribbon 1A and the thermal head 7A should be inverted so that the cyan ink image 15A can be formed on the lower side surface of the film 6A which contacts with the upper side surface of the film for magenta 6B. In addition, it is required that one of the outer films 6A and 6C should be a white or colored opaque film. In the hard copy obtained without using any base sheet 9, the films 6B and 6C serve also as a support for the film 6A on one hand and the films 6A and 6B serve also as a support for the film 6C. Further, if all of the three films 6A, 6B, 6C are transparent films, then there may be obtained a transparent positive like a slide suitable for observation by transmitted light. Such a transparent positive may be obtained also when a transparent plastic sheet is used as the base sheet 9.
In the second embodiment shown in FIGS. 4 and 5, again a halftone full color hard copy can be obtained by suitably controlling the amount of heat from the thermal heads 7A-7C.
Obviously, various modifications of the above embodiments are possible in the light of the above teachings. For example, while an ink ribbon 1 has been used as the ink bearing member in the above embodiments, there may be used also a drum having a layer of powdery ink adhering on the surface as disclosed in the aforementioned Japanese Laid Open Patent Application No. 82676/1980. Also, it is to be understood that the recording part is not limited to thermal or electrostatic recording systems as particularly shown in the above embodiments. All of those recording systems which enable forming an image through the step of transferring any image former onto a film may be employed for forming the recording part in the invention.
While in the embodiment shown in FIG. 4 or 5 there have been used three thermal heads 7A, 7B and 7C for high speed recording of polychromic images, it is also possible to use only a single thermal head for forming polychromic images according to the invention. In this case, to the single thermal head there are applied serially three different signals for forming a cyan image, a magenta image and a yellow image respectively. The ink ribbons 1A, 1B and 1C are also fed serially according to the sequence of the applied signals while reciprocating the film 6 three times per one picture area. Thus, the other two recording heads can be omitted.
The following third embodiment is a further improvement of the above second embodiment.
As seen from FIG. 5, the multilayer record composed of films 6A-6C has a correspondingly increased thickness. To reduce the thickness to a desirable value as a whole, it is required to make the respective films thinner. However, a thin film is apt to expand and shrink. If such thin films are superimposed, there occurs a relative shift of position between the films due to different expansion and shrinkage of the films, which brings about the problem that the three component color images get out of registration. The third embodiment solves the problem by giving to the individual color forming layers a suitable degree of adhesiveness.
FIGS. 6 and 7 illustrate the structure of a heat sensitive color forming sheet used in the third embodiment.
The color forming sheet is constituted of a ribbon-like base sheet 100 and a color forming layer 101 adhered on the base sheet. The color forming layer 101 is easily stripable from the sheet 100. The base sheet 100 is made of a material from which the color forming layer can be easily peeled and which exhibits good thermal conductivity. A preferred example of the base sheet 100 is a paraffin paper or paper impregnated with wax having a thickness in the range of 10 to 20 μm or a high molecular weight film of several μm in thickness. The color forming layer 101 is transparent and adhesive at least at the upper surface area. The layer 101 is formed of a mixture of a coloring dye such as leucocompound and a coupler such as phenol pulverized and dispersed in a binder. The layer 101 develops a color when either one of the coloring dye and the coupler is melted by heat and contacts with the other. The coloring layer 101 has a thickness in the range of some μ to about 50μ. For the purpose of easy separation of the coloring layer 101 from the base sheet 100, the sheet 100 and the layer 101 are chosen so as to have a little difference in width therebetween.
Preferred examples of the binder used in the heat sensitive coloring sheet include polyvinylalcohol, hydroxyethyl cellulose, carboxymethyl cellulose or styrene maleic anhydride copolymer. In case the binder itself has a sufficiently high adhesiveness, the coloring sheet may be formed by simply applying a layer of the above described mixture onto a supporting sheet 100 as shown in FIG. 7. If the binder has no or insufficient adhesiveness, the coloring sheet may be formed by applying to the support member 100 at first a first layer 120 of the above mixture and then applying a second layer 130 of a highly adhesive binder on the first layer 120 as shown in FIG. 8.
To improve the thermal reactivity it is preferred that wax or the like be added to the binder in addition to the above mentioned coloring dye and coupler. Further it is recommendable that capsules containing fixing agent and crushable by pressure be added dispersed in the binder to improve the stability after coloring. As the fixing agent there may be used any known substance which is able to reduce the phenol and can not be colored before and after the reaction.
FIG. 9 shows an embodiment of the color image forming apparatus employing the heat sensitive coloring sheets as shown in FIG. 6.
In FIG. 9, 200A, 200B and 200C are heat sensitive coloring sheets for developing yellow, magenta and cyan under the action of heat respectively. These three coloring sheets 200A, 200B and 200C are fed from supply drums 102A, 102B and 102C respectively and move in the direction of the arrow, passing between thermal heads 107A, 107B, 107C and rollers 103A, 103B, 103C respectively. The thermal heads 107A, 107B, 107C selectively heat the corresponding sheets. The heat reaches the coloring layer 101A through the supporting sheet 100A to form a monochromic image in the layer. Supplied from a supply drum 105 is a white or non-colored transparent base sheet 106. The heat sensitive coloring sheet 200A having a yellow image formed thereon enters the nip area between a pair of pressing rollers 116A and 117A where the coloring sheet 200A comes into contact with the base sheet 106 and the two sheets 200A and 106 are pressed together by the pressing rollers 116A, 117A. At the time, the coloring layer 101A firmly adheres to the base sheet 106 owing to the layer's own adhesiveness. Therefore, a strong bond is formed between the coloring layer and the base sheet. On the other hand, since, as previously noted, the coloring layer 101A is easily separable from the ribbon-shaped supporting sheet 100A and the bonding strength between the layer 101A and the supporting sheet 100A is preset sufficiently smaller than the bonding strength formed between the layer 101A and the base sheet 106, the supporting sheet 100A separates from the layer 101A after passing over the pressing roller 116A with deflection. The supporting sheet 100A apart from the coloring layer 101A is then taken up by a take-up drum not shown. Only the coloring layer 101A moves together with the base sheet 106 in a well bonded state.
Similarly to the above, a magenta image is formed on the heat sensitive coloring sheet 200B fed from the supply drum 102B and passed between the thermal head 107B and the roller 103B. When the sheet 200B passes through a pair of pressing rollers 116B and 117B, the coloring layer 101B having the magenta image thereon is bonded to the layer 101A already bonded on base sheet 106 and the supporting sheet 100B separates from the coloring layer 101B. The supporting sheet 100B apart from the coloring layer 101B is then taken up by a take-up drum not shown.
Also, on the heat sensitive coloring sheet 200C fed from the supply drum 102C there is formed a cyan image by the thermal head 107C. When it passes over the nip area of a pair of pressing rollers 116C and 117C, its coloring layer 101C having the cyan image thereon is bonded to the above coloring layer 101B supported on the base sheet 106. The supporting sheet 100C is separated from the coloring layer 101C and then taken up by a take-up drum not shown.
In this manner, three color images formed on the coloring layers 101A, 101B, 101C are superimposed on the same base sheet 106. Therefore, by applying to the three thermal heads 107A, 107B, 107C the corresponding control color signals in a synchronized relation, a natural color image can be obtained from the three monochromic images.
When the binder dispersed in the coloring layer 101 is sufficiently adhesive per se as in the case shown in FIG. 7, the coloring layer 101 becomes a layer of two-side adhesive. Therefore, in this case, the bonding strength between two coloring layers is very high. However, as will be understood from FIG. 9, the exposed surface of the undermost layer 101C is also adhesive, which is inconvenient for handling the record. To prevent it and protect the surface, in the shown embodiment, a non-colored transparent film 109 is supplied from a supply drum 108 to cover the exposed sticky surface of the layer 101C with the film 109 with the aid of a pair of pressing rollers 111 and 112.
If the binder dispersed in the first layer shown in FIG. 8 is not adhesive at all, then the exposed surface of the coloring layer 101C in FIG. 9 is not sticky and does not produce any problem. Therefore, in this case, it is unnecessary to cover the exposed surface with the transparent film 109. However, in any case, the rollers 103A, 103B, 103C disposed opposed to the thermal heads 107A, 107B, 107C should be covered, at least the roller circumferential surface, with a material to which adhesives can hardly adhere, for example, with a coating of fluororesin.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details can be made therein without departing from the spirit and scope of the invention.
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A recording method comprises the steps of selectively applying heat to individual heat sensitive color forming sheets each comprising a supporting sheet and a transparent color forming layer on the supporting sheet, which color forming layer is adhesive and develops a color under the action of heat but the colors developed in the individual layers being different from each other, thereby forming monochromic images in different colors on the individual color forming sheets; and separating each color forming layer with the formed monochromic image from the corrresponding supporting sheet and laying the separated individual layers on a common base sheet successively in layers making use of their own adhesiveness.
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CROSS-REFERENCE TO RELATED APPLICATION
This is a divisional of U.S. Ser. No. 08/812,467, filed Mar. 6, 1997, now U.S. Pat. No. 5,896,924, which is a continuation in part of U.S. Ser. No. 08/599,324, filed Feb. 9, 1996, now U.S. Pat. No. 5,706,892 which in turn is a continuation-in-part of U.S. Ser. No. 08/386,505, filed Feb. 9, 1995, (now abandoned).
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to well production control systems, and more particularly, to a computer controlled gas lift system.
2. Prior Art
In the operation of hydrocarbon production wells, gas lift apparati are occasionally employed to stimulate movement of fluid uphole. The operation ranges from simply pumping high pressure gas downhole to force fluids uphole to pumping additional fluids into the production fluid lowering the specific gravity thereof and thus increasing the "interest" of the fluid in migrating toward the surface. Gas lift apparati are also periodically employed when, a mixture of oil and water collects in the bottom of a gas well casing and tubing in the region of the producing formation and obstructs the flow of gases to the surface. In a "gas lift" well completion, high pressure gas from an external source is injected into the well in order to lift the borehole fluids collected in the well tubing to the surface to "clear" the well and allow the free flow of production fluids to the surface. This injection of gas into the well requires the operation of a valve controlling that injection gas flow known as a gas lift valve. Gas lift valves are conventionally normally closed restricting the flow of injection gas from the casing into the tubing and are opened to allow the flow of injection gas in response to either a preselected pressure condition or control from the surface. Generally such surface controlled valves are hydraulically operated. By controlling the flow of a hydraulic fluid from the surface, a poppet valve is actuated to control the flow of fluid into the gas lift valve. The valve is moved from a closed to an open position for as long as necessary to effect the flow of the lift gas. Such valves are also position instable. That is, upon interruption of the hydraulic control pressure, the gas lift valve returns to its normally closed configuration.
A difficulty inherent in the use of single gas lift valves which are either full open or closed is that gas lift production completions are a closed fluid system which are highly elastic in nature due to the compressibility of the fluids and the frequently great depth of the wells.
Prior art flow control valves for downhole applications, such as single gas lift valves per area, include the disadvantage of not providing a substantial amount of control over the exact amount of gas entering the well. This is because the valve is either open or closed and cannot be regulated. Hydraulically actuated downhole flow control valves also include certain inherent disadvantages as a result of their long hydraulic control lines which result in a delay in the application of control signals to a downhole device. In addition, the use of hydraulic fluids to control valves will not allow transmission of telemetry data from downhole monitors to controls at the surface.
Boyle et al patented a system capable of adjusting the orifice size of the valve through a range of values, thus providing a broader control over the amount of gas being injected into the system. U.S. Pat. No. 5,172,717 to Boyle et al discloses a variable orifice valve for gas lift systems. The system allows for adjustment of the flow through a particular valve body thereby allowing tailoring of the flow rate and alleviation of some of the previous problems in the art. The variable orifice valve allows greater control over the quantity and rate of injection of fluids into the well. In particular, more precise control over the flow of injection gas into a dual lift gas lift well completion allows continuous control of the injection pressure into both strings of tubing from a common annulus. This permits control of production pressures and flow rates within the well and results in more efficient production from the well.
The '717 patent solved many of the aforementioned problems with its variable orifice valve. Variable opening however provides some of its own inherent drawbacks such as lack of reliability of "openness" over time. More particularly, scale and other debris can build up and prevent movement more easily on orifice closures which are responsive to small increment movements and, in general, are only moved or adjusted by such small increments. Thus when conditions change downhole over time the variable orifice valve may be unable to comply with the changing conditions and would need to be replaced.
Another adjustable gas lift valve is disclosed in U.S. Pat. No. 5,483,988. The disclosure teaches a system having several parts or features but particularly includes an adjustable flow gas lift valve which includes a flow port and a plurality of differently sized nozzles selectively alignable with the port. Sensory devices are employed to maintain information about the state of the valve assembly. The variable nozzles are located on the actuator and, therefore, can be rotated into alignment with the orifice port to regulate the amount of gas flowing therethrough as desired.
Fully open/fully closed valves provide a large relative movement and tend to jar loose any buildup so that valve serviceability is maintained for a longer period of time. Therefore, these valves have a significant service life advantage over the more "advanced" variable opening valves. Also, where a plurality of these valves are employed in a given area, the closing of some (or opening) does not subject the individual valves to the same torsional forces because all flow is not pitted against a single structure. Thus opening or closing of the valves does not lead to excessive wear of valve components. The industry is in need of a system that experiences the benefit of variable orifice valves while concurrently benefitting from the serviceability of fully open/fully closed valves.
SUMMARY OF THE INVENTION
The above-discussed and other drawbacks and deficiencies of the prior art are overcome or alleviated by the adjustable flow gas lift valve of the invention.
In accordance with the invention, computer control and sensory information are combined with a series per unit area of fully open/fully closed gas lift valves to provide for intelligent downhole gas lift systems. Several embodiments of valve systems are set forth herein which provide adjustable control of the amount of gas injected into the tubing string and are responsive to downhole sensory data, processing and instructions.
In the first embodiment, a housing encloses an electrical motor which is paired with a resolver attached to a ball screw which is used to move a ported sleeve into various positions within the housing. Ports are present on the sleeve and at least one opening is employed on the housing of the tool. Thus, by aligning different numbers of ports in the sleeve with the main annulus opening, the amount of gas entering the tubing string is adjustable and controllable.
A second embodiment of the invention employs the elements of the first embodiment, however, also employs a multiported housing (as opposed to the single annulus opening of the first embodiment) having variously sized ports to provide even greater adjustability of the amount of flow of gas into the tubing string. In other respects, the embodiment operates as does the first embodiment.
The third embodiment of the invention employs an electric motor attached to a high pressure hydraulic pump. The pump discharges into an expandable bladder which is disposed adjacent several holes or slots in the housing, which slots lead to the casing annulus. As pressure increases in a chamber defined by the bladder, more of the holes or slots, or a larger percentage of the holes and slots, are blocked by the expanded bladder. By decreasing the pressure within the bladder the bladder will shrink and allow pressure from the annulus to move through the slots or holes.
In the fourth embodiment of the invention, fluid movement from the annulus to the tubing is electrically controlled by a motor operating a piston moving within a cylinder having ports to the annulus. Each port includes a seat and a check ball to seal the port, the check ball being displaceable (unseatable) by the movement of the piston within the cylinder. More specifically, as the piston moves along the cylinder it will contact an increasing number of check balls and unseat them from their respective seats thus allowing a proportionate amount of fluid from the annulus to flow into the tubing. This embodiment also includes a matching seat machined to compliment the piston such that if the valve is to be completely sealed, the piston may be moved into contact with the matching seat thus preventing all flow.
A fifth embodiment of the invention employs at least a plurality of commercially available, conventional fully open/fully closed valves per unit area This arrangement allows for control of the amount of fluid passing into the production fluid in a given area by allowing the operator to selectively open one or more of the plurality of valves located either annularly at a point in the tubing or staggered but closely to the same point. In other words there are clusters of nozzles where a single nozzle would have been in the prior art. It will be understood that the term operator is intended to mean an actual human or a computer processor either downhole or at the surface. The system allows incremental increase in flow rate.
A sixth embodiment is a variation on the fifth embodiment in that the basic premise of employing at least a plurality of individually fully operable/fully closeable valves is retained, however, each of the valves in this embodiment are of different sizes so that single valves or combinations thereof may be opened and closed to provide more control over the amount of fluid moving into the production tubing.
A seventh embodiment provides a helical valve body which rotatably opens or closes a helical flow path.
An eighth embodiment provides a flow control system in a side pocket mandrel to allow communication between the primary wellbore and the well annulus.
The above-discussed and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings wherein like elements are numbered alike in the several FIGURES:
FIG. 1 is a sectional illustration of a first embodiment of the invention;
FIG. 2 is a sectional view of a second embodiment of the invention;
FIG. 3 is a sectional view of a third embodiment of the invention;
FIG. 4 is a sectional view of a fourth embodiment of the invention;
FIG. 5 is a schematic view of the fifth embodiment of the invention having a multiplicity of valves of like dimensions;
FIG. 6 is a schematic plan view of FIG. 5 taken along lines 6--6;
FIG. 7 is a schematic view of a sixth embodiment of the invention having a multiplicity of different sized valves;
FIG. 8 is a schematic plan view of FIG. 7 taken along section line 8--8;
FIG. 9 is a perspective view of another embodiment of the invention employing a helical valve structure;
FIG. 10 is a cut away view of the body of the tool in which the valve structure of FIG. 9 is placed; and
FIG. 11 is a schematic view of the side pocket mandrel embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, a schematic illustration of the first embodiment of the invention is illustrated in cross-section. It will be understood by one of ordinary skill in the art that the entire device is intended to be attached to the outside of the tubing string and has relatively small dimensions. The invention is powered by electric line 10 connected to an electric motor 12 (and controlled by a downhole processor) having a resolver 14. The motor turns ball screw 18 through gear box 16 which provides axial movement of the sleeve discussed hereunder. Shaft 20 of ball screw 18 is preferably isolated from motor 12 by o-ring 22 which is mounted in housing 24. Housing 24 defines sleeve chamber 26 within which ported sleeve 28 is axially movable. A top section of sleeve 28, indicated as box thread 30 includes a pitch complimentary to ball screw 18 and is threaded thereon. Therefore, upon rotational actuation of ball screw 18, ported sleeve 28 is axially movable within chamber 16 of housing 24. Upon such movement of ported sleeve 28 individual ports 32 thereof are selectively alignable with main annulus opening 34, thus allowing fluid to flow from the annulus into chamber 26. Fluid pressure inside chamber 26 will unseat check valve 36 and flow therepast through tubing access opening 38 and into its desired destination of the production string (not shown). One of skill in the art will appreciate that check valve 36 is energized by spring 40 to maintain it in the closed position. This prevents fluid flowing within the tubing accessed by tubing access opening 38 from contaminating the gas lift valve or the annulus.
In the interest of maintaining the electric motor and the ball screw free from production fluid and other debris chamber 26 includes o-rings 42 and 44 which seal against ported sleeve 28.
Ported sleeve 28 is most preferably constructed from solid rod in which thread 30 is cut and an axial opening is drilled partially into the rod providing through passage for the ports 32. The solid portion of the rod left after machining is body seal 46. One of skill in the art will appreciate that in FIG. 1 the ported sleeve has been separated along the center line of the drawing to illustrate sleeve 28 in two positions i.e., partially activated and closed off. One of ordinary skill in the art will appreciate that in actuality body seal 46 is contiguous with the mirror (but moved over) image thereof on the other side of the drawing. In the second embodiment of the invention, referring to FIG. 2, only the major differences from the embodiment of FIG. 1 will be described. It should be noted that the embodiment of FIG. 2 provides even more control over the amount of flow of gas from the annulus to the production tubing string by providing individual ports on the ported sleeve of differing sizes and by employing a series of differently dimensioned ports through the housing to the annulus instead of employing a single annulus opening. Thus, by aligning desired ports of the ported sleeve with desired ports in the annulus opening a large degree of control is provided regarding the amount of gas (or other fluid) from the annulus which will pass through to the tubing string. Referring to FIG. 2, individual ports are identified by individual numerals due to their different sizes and to more clearly illustrate that fact. Port 50 is the largest port, ports 52, 54 and 56 become progressively smaller. Each of these ports are complimentary in size to ports 50', 52', 54' and 56' of the housing. Selective alignment among the ported sleeve ports and housing ports provides control over flow rate. The sleeve ports are arranged to be alignable in such a way that a smaller inner port is always aligned with a larger outer port unless the tool is completely open. This is to reduce erosional problems in the tool due to high flow rates through the valve. The inner sleeve is constructed from a higher resistance material and is therefore in a better position to handle the high flow.
Referring to FIG. 3, a third embodiment of the invention is illustrated in schematic form. Generally speaking, this embodiment depends upon an expandable bladder and a reservoir which is pressurizable to force fluid into the bladder thus expanding the same. Upon expanding the bladder, flow ports into the housing are blocked. When the flow ports are blocked, gas pressure from the annulus cannot reach the interior of the tubing. In particular, the invention includes a housing 60, interior chamber 62 wherein downhole electronics 64 are located and are attached to electric motor 66, pump 68 and reservoir 70. Bladder 72 is sealingly connected to the conduit 74 of the pump 68 such that upon command from downhole control line 76 to electronics 64 an electric motor 66 is actuated and turns pump 68, thus pumping fluid from reservoir 70 through conduit 74 into bladder 72, the bladder 72 expands in size and contacts the interior surface of chamber 62 thus blocking flow ports 78 which extend through housing 60. It will be understood that the more pressure in the bladder, the more force will be exerted against the ports and the less gas will flow. Flow ports 78 provide access to annulus gas pressure and extend to chamber 62. The ports 78 may be holes or slots as desired or as dictated by particular downhole conditions. Another part of chamber 62 is indicated as flow barrel 80 and it is this portion of the chamber which communicates between ports 78 and a reverse flow check valve 82 positioned within housing 60. The reverse flow check valve 82 is a commercially available part and does not require further discussion.
Upon deflation of bladder 72, ports 78 are opened and gas pressure from the annulus (not shown) will flow into flow barrel 80, push reverse flow check valve off seat 84 allowing the pressure of the gas to expand around the reverse flow check valve 82 and through flow ports 86 to the end of housing 60 where access opening 88 to the production tubing is provided.
It should be understood that the housing of the invention in embodiment 3 may be made up to the tubing or adapted in a wireline retrievable version to a side pocket mandrel.
In general, the pump of the invention may be merely a piston moving within a cylinder wherein as the piston extends toward the cylinder head the fluid is forced into the bladder end when the piston moves away from the cylinder head the bladder will, by elasticity, force the fluid back into the cylinder. It is not necessary for the pump to act as a conventional pump does in forcing more and more pressure since the movement of the bladder is not required to be substantial. Rather, the bladder need move only a small amount in order to seal off ports 78. The pump may simply move fluid out of the reservoir with extension of the piston and allow fluid into the reservoir with a retraction of the piston. It should also be understood that the pump may be of a conventional variety and will function equivalently to the simple pumping action just described.
Referring to FIG. 4, a fourth embodiment of the invention is disclosed is schematic form which uses a similar housing to that of embodiment 3, however, provides an alternate seal method for the ports. In this embodiment, downhole control line 90 extends from the surface to housing 92 wherein electronics and motor 94 are disposed and connected via a connecting rod 96 to piston 98. In order to maintain the motor and electronics free of fluids, piston ring 100 is supplied around piston 98. It should be noted at this point that piston 98 has a crowned section 102 which is machined to be complimentary to a matching seat 104 such that, if desired, the piston may be extended until it is seated in the matching seat which prevents any movement of fluid therepast.
In operation the gas lift valve is adjustable due to a plurality of ports 106 having machined seats 108 and complimentary check balls 110 which seat therein and seal the port. The balls are seated in such a manner that they protrude into the path of piston 98 within flow tube/cylinder 112. Upon movement of piston 98, contact with the check balls 110 will unseat them from seats 108 thus allowing fluid from the annulus (not shown) to flow through ports 106 past check balls 110 and into a flow tube/cylinder 112. It will be understood by one of skill in the art that the number of size of ports and check balls is preadjustable as well as their orientation such that when the piston moves a certain amount a controlled amount of fluid is allowed into the system. The amount of flow through the valve can be accurately maintained. Once fluid from the annulus has reached the flow tube/cylinder 112 it presses past reverse flow check valve 114 in the same manner as the prior embodiment. Since in other respects this embodiment is identical to that of embodiment 3 no further discussion hereof is required.
Turning now to FIGS. 5 and 6, another alternate embodiment of the invention is provided which allows for control over the amount of fluid provided to the production tubing. From this embodiment several conventional fully opened or fully closed valves 120 are actuatable at will either hydraulically or electrically from the surface or by downhole processor so the control over the amount of fluid entering the flow tube can be maintained. By opening 1, 2, 3 or 4 of the valves at any given time flow into the tube can be controlled to 25, 50, 75 or 100 percent of the allowable amount of gas. Since the valves are traditional on/off valves they are readily commercially available, easy to operate and provide a substantial service life.
Referring to FIGS. 7 and 8, one of ordinary skill in the art will appreciate that the general concept of the embodiments from FIGS. 5 and 6 is repeated, however, each of the fully opened/fully closed valves 130, 132, 134 and 136 are of different sizes thus providing even more control over the precise amount of fluid entering the tube. For example, and for purposes of argument, let valve 130 equal 10, valve 132 equal 20, valve 134 equal 30 and valve 136 equal 40 units per minute flow rate, then if valve 130 is opened alone ten units will flow, however, if valve 130 and 132 are opened together 30 units would flow whereas 132 opened alone would allow 20 units to flow, etc. It should be clear that any number of the valves can be opened together and all of them can be opened independently. This provides a great range of control over adjustability of the amount of fluid passing into the tube, yet, relies upon fully opened/fully closed valves which are easily commercially available and have been time tested by the industry.
In yet another embodiment of the invention, a helical valve is employed to variable control the inflow of gas into the production tube. FIG. 9 illustrates a perspective view of the valve member itself is illustrated; FIG. 10 places the valve member in context with the rest of the tool.
Referring to FIG. 9, helical valve body 150 is illustrated to include seat face 152 which is in the most preferred embodiment a polished face. One of skill in the art will appreciate that face 152 is visible four times in the drawing but represents only one structure. In FIG. 10, valve body 150 is illustrated in conjunction with the rest of the tool. The tool is in quarter cut-away form to illustrate the mating surface 154 against which face 152 abuts when the valve is closed. Upon moving(rotating) body 152 the distance between mating surface 154 and face 152 is varied. A larger distance translates to an increased flow rate and a smaller distance indicates a restricted flow. As one of skill in the art will appreciate, fluid flowing through the valve of the invention follows a helical path between surface 154 and face 152.
The tool of FIGS. 9 and 10 is actuated either longitudinally or rotationally by any conventional downhole movement device such as a hydraulic or electric downhole piston or motor assembly, a magnetic propulsion device, a racheting device, etc.
The valve flow path through the space created between surface 154 and face 152 can be either a constant one or one of varying dimension depending on how the helical structure is defined. For example, the amount of space in the flow path can be X at the larger end of the valve body and X+N at the narrower end of the valve body or that space may remain substantially constant along the path. In general, as one of skill in the art will appreciate, the flow path in this valve system will be of a generally rectangular cross section.
In order to automate the valve system of the invention sensors are installed at the interfacing sections of the valve structure so that both flow and openness of the valve can be measured. The valve of the invention is also preferably associated with a sensor or sensor array capable of providing information about the fluid pressure below the valve and that above the valve to allow a downhole processor, or even an uphole processor to monitor the "health" of the valve. Communication capability is also provided to allow the tool to send information to and receive instructions from the processor or from other tools.
Referring now to FIG. 11, a remotely controlled fluid/gas control system is shown and includes a side pocket mandrel 190 having a primary bore 192 and a side bore 194. Located within side bore 194 is a removable flow control assembly in accordance with the present invention. This flow control assembly includes a locking device 196 which is attached to a telescopic section 198 followed by a gas regulator section 200, a fluid regulator section 202, a gear section 204 and motor 206. Associate with motor 206 is an electronics control module 208. Three spaced seal sections 210, 212 and 214 retain the flow control assembly within the side bore or side pocket 194. Upon actuation by electronics module 208, control signals are sent to motor 206 which in turn actuates gears 204 and moves gas regulator section 200 and fluid regulator section 202 in a linear manner upwardly or downwardly or in a rotary manner within the side pocket 194. This movement (linear in the drawing) will position either the gas regulator section 200 or the fluid regulator section 202 on either side of an inlet port 216.
Preferably, electronics control module 208 is powered and/or data signals are sent thereto via an inductive coupler 218 which is connected via a suitable electrical pressure fitting 220 to the TEC cable 192 of the type discussed above. A pressure transducer 224 senses pressure in the side pocket 194 and communicates the sensed pressure to the electronics control module 208 (which is analogous to downhole module 22 as set forth in U.S. Ser. No. 08/599,324 previously incorporated herein by reference). A pressure relief port is provided to side pocket 194 in the area surrounding electronics module 208.
The flow control assembly shown in FIG. 11 provides for regulation of liquid and/or gas flow from the wellbore to the tubing/casing annulus or vice versa. Flow control is exercised by separate fluid and gas flow regulator subsystems within the device. Encoded data/control signals are supplied either externally from the surface or subsurface via a data control path 222 and/or internally via the interaction of the pressure sensors 224 (which are located either upstream or downstream in the tubing conduit and in the annulus) and/or other appropriate sensors together with the on-board microprocessor 208 in a manner discussed above with regard to FIGS. 6 and 7 of U.S. Ser. No. 08/599,324 previously incorporated herein by reference.
The flow control assembly of this invention provides for two unique and distinct subsystems, a respective fluid and gas flow stream regulation. These subsystems are pressure/fluid isolated and are contained with the flow control assembly. Each of the systems is constructed for the specific respective requirements of flow control and resistance to damage, both of which are uniquely different to the two control mediums. Axial reciprocation of the two subsystems, by means of the motor 206 and gear assembly 204 as well as the telescopic section 198 permits positioning of the appropriate fluid or gas flow subsystem in conjunction with the single fluid/gas passages into and out of the side pocket mandrel 190 which serves as the mounting/control platform for the valve system downhole. Both the fluid and gas flow subsystems allow for fixed or adjustable flow rate mechanisms.
The external sensing and control signal inputs are supplied in a preferred embodiment via the encapsulated, insulated single or multiconductor wire 222 which is electrically connected to the inductive coupler system 218 (or alternatively to a mechanical, capacitive or optical connector), the two halves of which are mounted in the lower portion of the side pocket 194 of mandrel 190, and the lower portion of a regulating valve assembly respectively. Internal inputs are supplied from the side pocket 194 and/or the flow control assembly. All signal inputs (both external and internal) are supplied to the on-board computerized controller 208 for all processing and distributive control. In addition to processing of offboard inputs, an ability for on-board storage and manipulation of encoded electronic operational "models" constitutes one application of the present invention providing for autonomous optimization of many parameters, including supply gas utilization, fluid production, annulus to tubing flow and the like.
The remotely controlled fluid/gas control system of this invention eliminates known prior art designs for gas lift valves which forces fluid flow through gas regulator systems. This results in prolonged life and eliminates premature failure due to fluid flow off the gas regulation system. Still another feature of this invention is the ability to provide separately adjustable flow rate control of both gas and liquid in the single valve. Also, remote actuation, control and/or adjustment of downhole flow regulator is provided by this invention. Still another feature of this invention is the selected implementation of two devices within one side pocket mandrel by axial manipulation/displacement as described above. Still another feature of this invention is the use of a motor driven, inductively coupled device in a side pocket. The device of this invention reduces total quantity of circulating devices in a gas lift well by prolonging circulating mechanism life. As mentioned, an important feature of this invention is the use of a microprocessor 208 in conjunction with a downhole gas lift/regulation device as well as the use of a microprocessor in conjunction with a downhole liquid flow control device.
All of the gas lift valves discussed herein are controllable by conventional means, however, it is highly desirable and preferable for the invention to have each of the valves controlled downhole by providing a series of sensors downhole to determine a plurality of parameters including exactly what fluid flow rate is required to be to correct whatever deviation the production tube is experiencing from optimal. These downhole sensors are most preferably connected to a downhole processing unit so that decisions may be made entirely downhole without the intervention of surface personnel. This is not to say that surface personnel are incapable of intervening in downhole operations since the downhole processor of the invention would certainly be connected to the surface via any known communication system which would allow information to be transferred to the surface and instructions transferred downhole if desired. In the absence of those instructions the gas lift valves of the invention would preferably set themselves based upon sensor input (see FIGS. 6 and 7 for schematic diagrams of the computer/sensor system employable with any of the embodiments of this invention). This is also most preferably connected to a complex communication and instruction system among different wells and remote areas alike. Further discussion of intelligent downhole tools may be found in Application Ser. No. 08/599,324 filed Feb. 9, 1996, which is a continuation-in-part of Application Ser. No. 08/386,505 filed Feb. 9, 1995, now abandoned, the entire contents of each of which are incorporated herein by reference.
While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation.
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Computer control and sensory information are combined with gas lift valve having a plurality of individual openings which are openable or closeable individually to provide varying flow rates of the lift gas. Each of the openings is controlled and is sensitive to downhole sensors.
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FIELD
[0001] The present disclosure relates generally to fill valves for toilets and more specifically, to systems directed towards preventing and detecting leaky flush valves in toilets and preventing waste of water during use of the same.
BACKGROUND
[0002] Occasionally, valves in toilets leak fluids. A leaky flush valve for example will cause water in the tank to leak out into the corresponding toilet bowl and ultimately down the drain. When a leak causes the water level in the tank to dip below its shut-off level, the water inlet valve typically opens in order to refill the tank. Between flushes, the tank is almost completely filled. As a result of the tank being ostensibly filled, a user may not be able to recognize that a valve such as the flush valve is leaking. A leaky flush valve that goes unrepaired will waste water which is of particular concern in an age when water has become increasingly scarce and expensive.
[0003] Previous approaches to resolving leaky toilet valves been designed so that the inlet valve of the toilet assembly is prevented from opening and thus disabling introduction of water until a person affirmatively flushes the toilet. As such, any valve that is leaking will empty the tank so that future flushes are only possible after the user manually fills the tank and/or fixes the leak. This is advantageous since water is conserved and users are put on notice that there is a leak due to the empty tank.
[0004] Aside from conservation of water, other considerations for solutions to leaky toilet valves include ensuring that any solution remains inexpensive and easy to implement on many different systems such as the approach taught in U.S. Pat. No. 4,965,891 (hereinafter “'891 patent”). However, the '891 patent requires that the inlet valve post of the system be modified which is not easily achievable by one skilled in the art such as a plumber or handyman. Moreover, this approach is relatively difficult to use in practice since it requires mounting a bracket to the valve float (which may additionally not be capable of receiving such a bracket). Perhaps most importantly, this approach fails to operate when the position of the valve float changes even slightly.
[0005] Other approaches have including positioning floats that slide along vertical posts of the toilet as is the case in U.S. Pat. Nos. 4,100,928 and 4,703,653. Each of these approaches, however, fail to describe a fill valve leak prevention device of relatively simple construction which is imperative in the field of toilets. Accordingly, there exists a need to provide a fill valve leak prevention device that addresses these and other needs in the art.
SUMMARY
[0006] The following simplified summary is provided in order to provide a basic understanding of some aspects of the claimed subject matter. This summary is not an extensive overview, and is not intended to identify key/critical elements or to delineate the scope of the claimed subject matter. Its purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later.
[0007] In some embodiments, a leak prevention device is provided for use in operation with a fill valve that is seated on a post in a toilet. The device may comprise a locking lever pivotable about a central pivot comprising a bias element operable to bias a first portion of the locking lever pivotally about the central pivot. The first portion may be operable to be pivotally positioned to prevent movement of a fill valve arm in communication with the fill valve.
[0008] The locking lever may be pivotally connectable to the central pivot that is in communication with the post. The central pivot may be associated with a fixed hinge in a toilet tank, the first portion further comprising a locking member operable to securely engage with a lever receiving surface of the fill valve arm.
[0009] In some embodiments, a second portion may be positioned opposite the first portion of the locking ever such that the first portion may weigh less than the second portion thereby creating the bias element of the locking lever. As such, the second portion may comprise a material density, material thickness, or material width that differs or is otherwise greater than the first portion. The center of gravity of the locking lever may likewise be positioned in the second portion. Optionally, the bias element of the locking lever may be provided by a coil or a spring in communication with the first portion and the central pivot.
[0010] The first and second portions may be joined at the central pivot thereby creating an angle defined by the first portion, the second portion, and the central pivot. The second portion of the locking lever may be operable to receive a flush actuator such as a chain, rope, wire, or string in communication with a flush lever. Further, the angle may be adjustable between one or more fixed positions.
[0011] In other embodiments, a leak prevention system is provided for use in operation with a fill valve seated on a post in a toilet. The system may comprise a float slidably coupled to the post underneath the fill valve, a link with an upper end and a lower end, the lower end being rigidly coupled to the float, an arm pivotally connected to the fill valve and pivotally connected to the upper end of the link, and a locking lever pivotally connected to a central pivot underneath the arm and the fill valve. In this respect, a first portion of the locking lever is configured to pivot about a central pivot and bias towards the link. The locking lever may further comprise a second portion positioned opposite the first portion so that a center of gravity of the locking lever is positioned in the second portion.
[0012] In some embodiments, the central pivot in the system may be associated with a fixed hinge in a toilet tank, wherein the first portion further comprising a locking member operable to securely engage with a lever receiving surface of the fill valve arm. In this respect, the lever receiving surface may comprise teeth, projections, grooves, members or an otherwise friction-inducing surface to securely receive and engage the locking member of the first portion. The locking member may be integrally formed with the first portion or removable attached thereto. The first and second portions may likewise be joined at the central pivot of the locking lever thereby creating an angle defined by the first portion, the second portion, and the central pivot. The angle may also be adjustable between one or more fixed positions.
[0013] In this system, the first portion may weight less than the second portion so that the first portion naturally pivots towards the link and the second portion naturally pivots towards the fill valve. To achieve this weight distribution, the second portion may comprise a material density, material thickness, or material width that differs or is greater than that of the first portion. A flush actuator may extend from the locking lever in this embodiment, wherein the flush actuator may be operable to cause the first portion of the locking lever to pivot about the central pivot away from the link. The flush actuator may comprise a chain, rope, wire, beam, member or string in communication with a flush lever.
[0014] In other embodiments, the central pivot may be in communication with the post wherein a lever attachment mechanism may pivotally receive the locking lever at the central pivot, the lever attachment mechanism disposed on the post between the fill valve and the float. The lever attachment mechanism may be removably attached and/or slidable coupled to the post or the lever attachment mechanism is integrally formed with the post.
[0015] The system may likewise comprise a lever locking receiver mechanism that is disposed on the link underneath the upper end the same. The first portion of the locking lever may therefore be operable to pivot about the central pivot until being securely received by the lever locking receiver. The lever locking receiver mechanism may comprise an annular ring, shoulder, flange or projection operable to securely receive the first portion of the locking lever. The lever locking receiver mechanism may likewise be integrally formed with the link or be removably attached thereto and slidable between one or more fixed positions.
[0016] In other embodiments, a method is provided for preventing a toilet tank with a fill valve seated above a post from leaking. The method may comprise the following steps: pivotally connecting a locking lever to a central pivot in communication with the fill valve (which may be directly or indirectly to the corresponding post), wherein a first portion of the locking lever is operable to bias away from the post; and preventing the fill valve from actuating the flow of fluids into the toilet tank by pivoting the first portion of the locking lever about the central pivot towards a fill valve link mechanically attached to a float slidably couple to the post so that an actuating arm pivotally connected to the link and the fill valve is prevented from translating.
[0017] The method may further comprise: unlocking the fill valve by actuating a flush actuator operably connected with the locking lever causing the first portion of the locking lever to pivot about the central pivot away from the fill valve link so that the fill valve is operable. The method may additionally comprise pivotally connecting the central pivot of the locking lever with a lever attachment mechanism disposed on the post, wherein the central pivot is in communication with the post and/or securely engaging a first portion of the locking lever with a lever locking receiver mechanism disposed on the link, wherein the central pivot is in communication with the post.
[0018] In other embodiments, a leak prevention device may also be provided for use in operation with a fill valve with a fill valve arm in a toilet. The device may comprise a pivotable locking lever having a first portion positioned to pivot into and out of contact with the fill valve arm or an extension thereof. The fill valve arm affects actuation of the fill valve to modulate fluids from entering the toilet tank, wherein the pivotable locking lever is operable to contact or is capable of contacting the fill valve arm thereby prohibiting the operation of the fill valve.
[0019] To the accomplishment of the foregoing and related ends, certain illustrative aspects are described herein in connection with the following description and the annexed drawings. These aspects are indicative, however, of but a few of the various ways in which the principles of the claimed subject matter may be employed and the claimed subject matter is intended to include all such aspects and their equivalents. Other advantages and novel features may become apparent from the following detailed description when considered in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a schematic illustration of a fill valve leak prevention system in a first position between flushes.
[0021] FIG. 2 is a schematic illustration of the system FIG. 1 in an engaged position to prevent the fill valve from actuating flow of fluids into the toilet tank.
[0022] FIG. 3 is a schematic illustration of the system of FIG. 1 just after being released from the engaged position of FIG. 2 .
[0023] FIG. 4 is a schematic illustration of another fill valve leak prevention system in a first position between flushes.
[0024] FIG. 5 is a schematic illustration of the system FIG. 4 in an engaged position to prevent the fill valve from actuating flow of fluids into the toilet tank.
[0025] FIG. 6 is a schematic illustration of the system of FIG. 4 just after being released from the engaged position of FIG. 5 .
DETAILED DESCRIPTION
[0026] The fill valve leak prevention device and method of use described herein are configured to conserve vital resources such as water, manufacturing resources, and time associated with repairs and system maintenance that otherwise require attention. Accordingly, the device and systems described herein depict a fill valve leak prevention device moving between unlocked and locked positions.
[0027] Specifically, FIG. 1 depicts a side view of a fill valve leak prevention device 10 assembled within a tank 14 of a toilet 1 (each not depicted) for use with a fill valve 15 . In FIG. 1 , the leak prevention device 10 is depicted unlocked with associated float 26 in a down position. FIG. 2 depicts the embodiment of FIG. 1 with valve 15 in a locked engagement so arm 47 is prevented from translating such that valve 15 is prevented from refilling tank 14 . FIG. 3 similarly depicts the embodiments of FIG. 1-2 just after valve 15 has been released from its locked engagement in FIG. 2 .
[0028] Device 10 is disposed internal to tank 14 above the associated bowl 12 . Typically, a flush actuator 55 such as a chain is in communication with a flush actuator (not depicted) that allows the user to pull, push, or otherwise actuate toilet 10 in order to cause a flush. Accordingly, actuating actuator 55 in conventional flush systems causes fill valve arm 47 to translate associated fill valve 15 to allow ingress of water into tank 14 between flushes.
[0029] Fill valve 15 may be seated above an associated post 17 that mounts to the lower surface of the tank 14 and slidably couples to float 26 . In this regard float 26 may slide between pre-flush and flush configurations along post 17 as described. Post 17 may be constructed from a variety of materials and/or shapes such as tubular, rectangular, or otherwise shaped cross sections so that associated float 26 may slide therealong between positions with its correspondingly shaped internal float guide.
[0030] A lever attachment mechanism 19 may also be operatively coupled to the post 17 above float 26 and below fill valve 15 . Mechanism 19 may be integrally formed with post 17 or removably attached thereto, wherein mechanism 19 may be slidably coupled or fixedly attached in one or more fixed positions on post 17 . In a preferred embodiment, mechanism 19 is an annular ring, collar, shoulder, or flange that substantially encircles the external surface of post 17 at a predetermined position, wherein one or more projections of mechanism 19 extend away from post 17 towards link 27 terminating in lever central coupling pivot 31 . Pivot axis of pivot 31 may be oriented substantially orthogonal relative to post 17 and substantially parallel with the plane of the lower surface of the tank.
[0031] Arm 47 in turn may pivotally couple to fill valve 15 on one end and on its opposite end may be pivotally coupled to an upper end of link 27 underneath cap 37 . In some embodiments, a link end of arm 47 slidably mounts to the upper end of link 27 with C-shaped or U-shaped coupling members and is securely fastened thereto by cap 37 . Cap 37 may comprise internal threads configured to fasten with external threads of link 27 . However, link 27 may optionally comprise integrally formed fasteners such as a hook, loop, pin, dowel, snap/fit engagement or the like so that arm 47 is slidably received by and/or fastened to the upper portion of link 27 .
[0032] A locking lever 45 is also provided pivotally coupled to mechanism 19 at central pivot 31 . Specifically, lever 45 couples to pivot 31 at a central pivot of lever 45 thereby dividing lever 45 into first 29 and second portions 30 . A hinge, axel, rotatable pin, or the like may be provided to couple pivot 31 and lever 45 together so that the desired pivoting movement between mechanism 19 and lever 45 may be achieved.
[0033] In this regard, when comparing FIG. 1 and FIG. 2 , it can be seen that first portion 30 of lever 45 pivotally moves about pivot 31 until contacting link 27 . Further, because portions 29 and 30 are joined at central pivot 31 , lever arm angle 35 is provided defined between portions 29 and 30 . Likewise, lever 45 comprises a center of gravity 85 positioned substantially in portion 29 . In practice, when the water level of tank 14 decreases, portion 30 of lever 45 is operable to naturally bias towards link 27 in order to prevent arm 47 from translating so that valve 15 in turn is prevented from opening and thus actuating ingress of fluids into tank 14 between flushes. Because of the unique positioning of center of gravity 85 in portion 29 , lever 45 is naturally biased towards having portion 29 pivot about pivot 31 towards post 17 with corresponding portion 29 being constructed to pivot about pivot 31 towards link 27 .
[0034] Lever arm angle 35 may be any angle less than 180 degrees and preferably, more than 90 degrees. In some embodiments, angle 35 may be adjustable which provides additional ease of installation as well as ability to customize to design constrains since relative distance between float 26 , post 17 , and valve 15 has no effect on whether lever 45 can be incorporated into tank 14 .
[0035] An alternative approach to achieving the bias element of lever 45 includes provision of an optional coil or a spring in communication with central pivot 31 and portion 30 so that portion 30 in turn comprises a resistance element that causes portion 30 to naturally pivot about pivot 31 until contacting link 27 and ultimately mechanism 65 as required. Preferably, however, portion 29 may be heavier than portion 30 . Portion 29 may therefore be constructed from denser or heavier materials) and/or respective material thicknesses, length or width of portion 29 may differ with respect to those of portion 30 . As a result, lever 45 will comprise a bias element that causes portion 30 to naturally pivot about pivot 31 towards link 27 . The aforementioned difference in weight between portions 29 and 30 may be optionally achieved by removably positioning ballast to one or more portions 29 and 30 as desired.
[0036] When comparing FIGS. 1 and 2 , it can be seen that FIG. 2 clearly shows lever 45 in an engaged position, wherein arm 47 is in a raised position relative to FIG. 1 and portion 30 is seated underneath or otherwise in communication with mechanism 65 . Portion 30 therefore contacts mechanism 65 thereby imparting a substantially upward resistance force depicted by the upward arrow. In practice, if tank 14 comprising the herein described lever 45 and associated system comprises a leak, lever 45 as described prevents float 26 and corresponding link 27 from moving arm 47 . In turn, arm 47 is prevented from actuating valve 15 to the extent that fluids are prevented from being introduced into tank 14 via valve 15 thereby unnecessarily wasting water that otherwise would result if the refilling action caused by valve 15 were left unchecked.
[0037] FIG. 3 depicts lever 45 and it associated system after actuator 55 pulls and/or moves portion 29 to pivot away from post 17 towards link 27 . In this respect, portion 30 of lever 45 pivots about pivot 31 away from link 27 towards post 17 thereby releasing its engagement with mechanism 65 . By removing portion 30 from being securely engaged with mechanism 65 , link 27 and associated arm 47 are now free to translate to an unlocked position during a flush as represented by downward arrow of FIG. 3 . Thus, pulling or otherwise moving actuator 55 may cause portion 29 to rotate about pivot 31 towards link 27 and rotate portion 30 about pivot 31 towards post 17 (i.e. opposite the pivoting movement caused by the bias element of lever 45 ). By pivoting portion 30 away from link 27 in this manner, arm 47 is no longer prevented from translating since the upward, preventive force imparted by portion 30 to mechanism 65 has been released. As a result valve 15 may now permit ingress of water into tank 14 during tank 14 refilling (since link 27 , cap 37 , associated float 26 , and arm 47 are able to translate freely between flushes).
[0038] As can be seen, mechanism 65 may comprise an annular ring, shoulder, flange, collar, projection or the like operable to securely receive and engage with arm 47 once arm 47 has naturally pivoted into position underneath mechanism 65 . Optionally, mechanism 65 may be integrally formed with link 27 below cap 37 at a predetermined position dependent upon corresponding size and shape of lever 45 . Preferably, mechanism 65 may be removably attached to link 27 at one or more fixed positions on link 27 .
[0039] In another embodiment depicted in FIGS. 4-6 , a similar locking lever 145 is provided moving between engaged and translatable positions so that lever 145 may prevent corresponding fill valve 15 and fill valve arm 47 from translating and in turn activating fill valve 15 to refill tank 114 . FIG. 4 specifically depicts lever 145 when pivotally attached to central pivot 131 on a fixed hinge inside tank 14 and in communication with valve 15 (e.g. directly to post 17 or any other feature or component operatively coupled thereto), wherein corresponding float 26 is positioned in a down position since the tank 14 is empty. FIG. 5 by contrast depicts the same system of FIG. 4 whereas tank 14 now comprises fluids such that float 26 is oriented in an upward position with portion 130 of lever 145 securely engaged with arm 47 (thereby preventing translation and thus actuation of arm 47 ). Finally, FIG. 6 depicts the previously described system of FIGS. 4-5 just after corresponding actuator 55 has been pulled or otherwise moved so that portion 130 is caused to pivot about pivot 131 towards link 27 thereby releasing its secure engagement with arm 47 .
[0040] As can be seen in FIGS. 4-6 , arm 47 further comprises a locking member surface 152 disposed on the an underside of arm 47 adjacent to or otherwise nearby where arm 47 couples to link 27 underneath cap 37 . Portion 129 of lever 145 may optionally comprise a locking member 150 disposed on distal end of portion 129 (opposite pivot 131 ) that extends away from the portion 129 . In this respect, instead of securely engaging with link 27 as in the embodiments of FIGS. 1-3 , portion 129 of lever 145 is operable to pivot about central pivot 131 until contacting arm 47 and securely engaging with corresponding surface 152 as shown in FIG. 5 .
[0041] Portion 130 of locking lever 145 may optionally comprise corresponding locking member 150 which may be a blade or extruded member that extends from the distal end of portion 130 until contacting lower locking surface 152 of arm 47 . It can be seen that portion 130 engages with arm 47 at locking surface 152 , such that locking surface 152 is operable to receive lever 45 and/or any corresponding member 150 . When lever 145 or member 150 is seated against or otherwise in contact with surface 152 , advantageously lever 145 is naturally maintained in a secure engagement that prevents translation and thus actuation of arm 47 . In so doing, arm 47 is prevented from actuating valve 15 such that valve 15 is incapable of introducing fluids into tank 14 until portion 130 disengages with arm 47 (see FIGS. 5 and 6 ).
[0042] Similar to lever 45 , when comparing FIGS. 4-6 , it can be seen that first portion 130 of lever 145 is operable to pivotally moves about pivot 131 until contacting arm 47 . Further, because portions 129 and 130 are joined at central pivot 131 , when the water level of tank 14 ascends ( FIGS. 4 to 5 ) or descends ( FIGS. 5 to 6 ), portion 130 of lever 145 is operable to naturally bias towards surface 152 of arm 47 in order to prevent arm 47 from translating so that valve 15 in turn is prevented from opening and thus actuating ingress of fluids into tank 14 between flushes.
[0043] The unique bias element comprised by lever 145 that causes portion 129 to pivot about pivot 131 towards post arm 47 with corresponding portion 130 being constructed to pivot about pivot 131 towards link 27 may be preferably be achieved as follows. Portion 129 may be heavier than portion 130 , wherein portion 129 may be constructed from denser or heavier materials) and/or respective material thicknesses, lengths or width of portion 129 may differ with respect to those of portion 130 . As a result, bias element of lever 145 causes portion 130 to naturally pivot about pivot 131 towards arm 47 to prevent arm 47 from translating or otherwise moving to actuate refill by valve 15 . The aforementioned difference in weight between portions 129 and 130 may be optionally achieved by removably positioning ballast to one or more portions 129 and 130 as desired. Alternatively, the bias element of bias element of lever 145 may comprise an optional coil or a spring in communication with central pivot 131 and portion 130 so that portion 130 in turn comprises a resistance element that causes portion 130 to naturally pivot about pivot 131 until contacting arm 47 .
[0044] In some embodiments, member 150 may comprise a locking blade constructed from stainless steel or other metal with binding teeth configured to etch or dig into surface 152 . This induces friction between member 150 and surface 152 (which may be plastic). Although metal may be preferred, member 150 may utilize any material more rigid than surface 152 . Member 150 may also comprise a relatively sharp edge configured to etch into surface 152 to induce friction securely engage member 150 to arm 47 thereby preventing arm 47 's pivoting movement.
[0045] The present device 10 differs significantly from the approach taught by U.S. Pat. No. 5,769,111 (hereinafter “'111 patent”). The '111 patent teaches a leak prevention device but is of relatively complex construction and its installation consists of a buoyant cup that must be mounted underneath a valve float. The device functions by preventing the float from moving down between flushes by the buoyant cup. A mount assembly attaches to the underside of the float below the water such that the cup is normally immersed in water. When the water drops, the weight of the float causes the cup to pivot towards the post of the float until it locks the float in place. To unlock the cup of the '111 patent, a chain is moved thereby disengaging the cup from contacting the float so that refilling may take place. This approach requires intricately machined parts, a mount to the float, a buoyant cup, and a pivot arrangement that relies upon the weight of the float for leak prevention functionality.
[0046] By contrast, the approaches described in the embodiments of FIGS. 1-6 secure the actuating arm 47 in order to prevent actuation of fill valve 15 through a relatively simple system that incorporates locking lever 45 / 145 and associated portions 29 / 129 and 30 / 130 . Lever arm 47 is maintained in place upwards by the tendency of locking lever 45 / 145 to pivot about pivot 31 / 131 (either by contacting arm 47 itself or contacting and securely engaging link 27 ). This advantageously provides a simpler solution to the foregoing problems since it does not rely upon levels of water floating a buoyant cup or the weight of a float.
[0047] The fill valve leak prevention system and device as taught and described herein is able to be installed on any variety of toilets. Many alterations and modifications may be made by those having ordinary skill in the art without departing from the spirit and scope of the embodiments disclosed and described herein. Therefore, it is understood that the illustrated and described embodiments have been set forth only for the purposes of examples and that they are not to be taken as limiting the embodiments as defined by the following claims. For example, notwithstanding the fact that the elements of a claim are set forth below in a certain combination, it must be expressly understood that the embodiments include other combinations of fewer, more or different elements, which are disclosed above even when not initially claimed in such combinations.
[0048] The definitions of the words or elements of the following claims are, therefore, defined in this specification to not only include the combination of elements which are literally set forth. It is also contemplated that an equivalent substitution of two or more elements may be made for any one of the elements in the claims below or that a single element may be substituted for two or more elements in a claim. Although elements may be described above as acting in certain combinations and even initially claimed as such, it is to be expressly understood that one or more elements from a claimed combination can in some cases be excised from the combination and that the claimed combination may be directed to a subcombination or variation of a subcombination(s).
[0049] Insubstantial changes from the claimed subject matter as viewed by a person with ordinary skill in the art, now known or later devised, are expressly contemplated as being equivalently within the scope of the claims. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are defined to be within the scope of the defined elements. The claims are thus to be understood to include what is specifically illustrated and described above, what is conceptually equivalent, what can be obviously substituted and also what incorporates the essential idea of the embodiments.
[0050] What has been described above includes examples of one or more embodiments. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the aforementioned embodiments, but one of ordinary skill in the art may recognize that many further combinations and permutations of various embodiments are possible. Accordingly, the described embodiments are intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims. Furthermore, to the extent that the term “includes” is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term “comprising” as “comprising” is interpreted when employed as a transitional word in a claim.
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A leak prevention device is provided for use in operation with a fill valve with a fill valve arm in a toilet tank. The device may comprise a pivotable locking lever having a first portion positioned to pivot into and out of contact with the fill valve arm or an extension thereof. The fill valve arm affects actuation of the fill valve to modulate fluids from entering the toilet tank, wherein the pivotable locking lever is operable to contact or is capable of contacting the fill valve arm thereby prohibiting the operation of the fill valve.
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This application is the U.S. National Phase of, and Applicant claims priority from, International Application Number PCT/NL2006/000427 filed 17 Aug. 2006 and European Application bearing Serial No. 05076906.6 filed 17 Aug. 2005, which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
The invention is directed to a process and an apparatus for gas treatment, in particular for the purification of methane rich gas streams, such as gas obtained from the conversion of waste or other types of organic matter (“biogas”). More in particular, the present invention is directed to the production of purified biogas (such as landfill gas, digester gas), which finds use as an efficient energy source. Thus, the present invention is directed to a process and an apparatus to purify such methane rich gases to obtain a gas of a quality that is comparable to that of natural gas.
Various methods are known to produce biogas from organic matter, e.g. by the anaerobic digestion of organic waste (including manure, wastewater sludge, municipal solid waste, etc.). Apart from methane, these fermentation processes usually also produce together large quantities of CO 2 (typically about 30-50 vol. % of the produced gas volume may be CO 2 ) and smaller quantities of sulphides and compounds such as vinyl chloride as well as other impurities. The gas must be removed with mechanical work and then treated before it can be used as an energy source. The purified gas can be transported in cylinders, liquefied in cryogenic tanks, used for on-site power generation or piped to a nearby energy demand. The last two options appear to have the widest growth potential.
Methane gas is produced in large quantities in for example, landfill sites and certain sewage works. It is currently recovered in a few locations but the bulk of this potentially valuable energy reserve is lost. Exploitation of landfill gas, digester gas and other types of biogas has been limited particularly because no equipment is available for economically processing the gas into transportable form, which includes purification of the gas. Desirably the equipment itself should be transportable since, in many cases (e.g. landfill sites), the gas source will only produce viable quantities of gas for a limited time and the installation of permanent plant would not be justified.
Removing moist, H 2 S, SO 2 , halogens, siloxanes and/or other contaminants is essential to purifying landfill gas, digester gas and biogas for use as an efficient energy source. Although several well established technologies are used, the provision of a viable process for cleaning landfill gas, digester gas and biogas remains a problem. Various methods of gas treatment processes are already known for this purpose. These processes are focused on either the reduction of the moisture level content, CO 2 extraction, H 2 S removal or the removal of one or more contaminants present in the gas mixture. The disadvantage of the known methods is that they do not to a sufficient extent permit the removal of many of the undesirable substances comprised in gases of the above-mentioned kind. Moreover, present processes are not entirely without disadvantages regarding the level of engine corrosion, wear, maintenance costs, generated process waste, disposal costs and composition of gas mixture as end-product. Finally, the prior art does not show how substances that are removed may be reused.
GB-A-1 565 615 describes a process for the separation of CO 2 from methane wherein the mixture of the two compounds is cooled two form a gas/liquid mixture which is subsequently fractionated.
U.S. Pat. No. 4,681,612 describes a process for separating a landfill gas to produce a CO 2 product stream and a fuel-grade methane product stream. The process involves cryogenic distillation and a membrane separation step to produce the fuel-grade methane stream.
In the art, also contaminants absorption processes, such as processes based on activated carbon filters, in which most contaminants are removed, are known. However, the regeneration costs and disposal costs for activated carbon are high. In addition carbon filters have a great affinity for moisture thus reducing adsorption efficiency. Furthermore, other absorption methods are applied such as molecular membrane filters, activated polymeric membrane filters and silica-gel. Yet, methods used still do not achieve quality level necessary for use as an efficient energy source.
Other absorption methods include contaminants elimination through organic dissolution. This process is in practice rather complicated because the contaminants targeted are highly volatile. Due to its chemical affinity for water or CO 2 , it is also possible to remove siloxanes by using condensation methods. In general however, lower elimination levels are achieved through this method.
The chemical make up of the landfill gas, digester gas and biogas differs from site to site. Some sites may have higher sulphur content, while others may have higher traces of siloxanes, and still others may have traces of heavy hydrocarbons, which can increase the risk of engine knocking when the gas is applied in a gas engine. As such, the gas treatment system has to be customized for each site depending on the levels of contaminants and engine requirements. Typical requirements for a biogas to be used in a gas engine are given in Table 1.
TABLE 1
Minimum acceptable level of contaminants for gas engines
Contaminant
Level
Remarks
Hydrogen Sulphide
<200 mg/Nm 3 methane
Engine corrosion
Halides (Chlorine,
<100 mg/Nm 3 methane
Engine corrosion
Fluorine)
Ammonia
<50 mg/Nm 3 methane
—
Particulates (Dust)
<3-10 μm
—
Hydrocarbons > C5
<5 mg/Nm 3 methane
Increase engine
knocking
Siloxanes *)
<2 mg/Nm 3 methane
Increase maintenance
Reduced engine
performance
Moisture
<80% RH at lowest
Acid formation
temperature
*) Depending on maintenance interval as contracted with gas engine manufacturer. Indicated value is average.
Of these contaminants siloxanes are the most aggressive and usually pose the biggest problems. Siloxanes break down into a white abrasive powder, which may damage equipment installed downstream (boilers, combustion engines, turbines, catalysts, or the like). Also, traces of siloxanes, hydrogen sulphide, halogens and other minerals have been reducing the performance and increasing maintenance of the generators. To the present inventor's best knowledge, to date no complete package is offered to remove large part of moist, H 2 S, SO 2 , halogens, siloxanes and other contaminants involved.
An object of the present invention is to provide a method which will permit the removal of several of the contaminating substances comprised in biogas. A further object is that the removal of those substances may take place in a simple manner so that the method is not dependent on complicated technical installations. Furthermore, the process of the invention should provide a clean gas having a level of contaminants that is sufficiently low to allow for problem-free application in for instance a gas engine. In other words, in accordance with the present invention the end-product should have a composition that provides a product that is close to natural gas quality. A further object is the process of the present invention should produce as little waste as possible and should be energy efficient.
SUMMARY OF THE INVENTION
It was found that these objects can be met by a process wherein a biogas stream is purified by employing at least two cooling steps. Thus, in a first aspect the present invention is directed to a process for producing a purified methane comprising gas stream (P) from a methane containing gas stream (A), comprising the steps of:
(a) pressurising said methane containing gas stream (A) and subsequently cooling it, whereby a stream comprising condensed contaminants (C) and a methane comprising stream (B) are obtained;
(b) optionally feeding said methane comprising stream (B) to an adsorption unit and/or a catalytic conversion unit, whereby the concentration of contaminants in stream (B) is further decreased; and
(c) cooling the methane comprising stream (B) to a temperature which is sufficient to condensate CO 2 from said stream (B), whereby said purified methane comprising gas stream (P) is obtained and a stream (E) comprising CO 2 . It is preferred to carry out optional step (b).
In one embodiment the gas treatment process of the present invention may comprise three steps. In the first step biogas (or any other methane containing gas that needs to be purified) is pressurised and fed to an alternating condenser wherein moist (water), H 2 S, SO 2 , halogens, siloxanes and other contaminants are removed from the gas mixture. Next, the gas mixture is fed to a so-called polisher device, containing a suitable catalyst/adsorbent to remove remaining contaminant traces.
Suitable catalyst/absorbents are materials that comprises a desulphurization agent, such as iron oxide Fe 2 O 3 . After the desulphurization agent has reacted with the sulphur compound, it may be reactivated, e.g. by reacting it with oxygen (e.g. from air). The catalyst/absorbents preferably also comprises a adsorbing function, e.g. provided by its pores, which enable adsorption of other contaminants like siloxanes in the pores.
One suitable catalyst/adsorbent that has been developed by the present inventors and that will be marketed under the trade name SOXSIA™ and is designed to convert H 2 S to elementary sulphur and to adsorb other contaminants like siloxanes in the pores of the SOXSIA™ adsorbent.
When the desulphurization agent in the catalyst/absorbent is for instance iron oxide, Fe 2 O 3 , H 2 S may be removed by the chemical reaction: Fe 2 O 3 +3H 2 S—>Fe 2 S 3 +3H 2 O.
The catalyst/absorbent can by reactivated using oxygen from air by means of the reaction: 2Fe 2 S 3 +3O 2 →2Fe 2 O 3 +6S.
During reactivation, the elementary sulphur may be retained in the pores of the adsorbent. For reactivation, a small flow of air is circulated though the catalyst bed. Since the reactivation reaction is exothermal, heat is produced. This heat will consequently evaporate the adsorbed siloxanes and other contaminants and the catalyst/absorbent is regained in its regenerated form.
After each reactivation, the performance of the catalyst on desulphurization is reduced due to the retaining sulphur. To regenerate the catalyst and return to 100% performance, the sulphur is preferably removed by heating en melting of the elementary sulphur using an inert gas such as nitrogen at elevated temperature, e.g. at temperatures of 200-300° C.
The regeneration is preferably performed in a separate unit. Therefore, in general the spent catalyst/absorbent will be replaced with fresh one after which the spent catalyst/absorbent can be regenerated, etc.
The process may then be concluded with a deep cooling process to achieve CO 2 removal by partial condensation of the CO 2 and removal thereof from the gas.
The undesirable compounds (contaminants) of the gas are extracted, and may be reused. The purified gas end-product produced in accordance with the present invention was found to be equivalent to natural gas (sellable gas) quality, typically having a composition that meets the requirements given in Table 1 hereinabove, and can be injected in the natural gas grid. It may also be compressed so it can be used as fuel for vehicles (CNG=Compressed Natural Gas) or used as a fuel for LNG (Liquefied Natural Gas).
DETAILED DESCRIPTION OF THE INVENTION
In a preferred embodiment, the first step comprises chilling the methane containing gas stream (A) using a heat-exchanger. Very suitable is a triple tube gas/gas-heat exchanger, wherein the triple tube is used to collect the ice formation without causing obstruction in the heat exchangers for a certain period of time. In this way a constant gas flow for a prolonged period of time can be provided. Preferably the cooling in step (a) is carried out to a temperature of approximately −25° C. By chilling the gas moisture and most other contaminants condense. It was found that as the moisture freezes, it maytrap the contaminants, thereby reducing the chance for carryover in the outgoing treated gas, which improves process efficiency considerably. Moisture residue is separated and drained at various chilling and separation points. In this way, nearly all (e.g. up to 99 wt. %) of the water in the gas stream may be condensed or frozen out. In this way, it can be attained that most of the heavy hydrocarbons (viz. C 5 or higher) can also condense, and virtually all siloxanes can also be removed. So by removing a considerable part of the remaining moisture, the adsorption efficiency of the adsorber and/or catalytic conversion unit in step (b) is drastically improved; and the chance for condensation down stream of the GPP is virtually eliminated.
Optionally in step (b) particulate matter (typically having a size of from 0.3 to 0.6 μm) can be removed, for instance using an adsorption unit and/or a catalytic conversion unit, such as a single unit comprising a bed of solid particles, such as SOXSIA™ mentioned hereinabove.
In accordance with the present invention there may be produced a clean, energy-rich methane gas, having a methane content up to 90 mole %. For comparison Groningen natural gas contains 81.3 mole % CH4 where High-Cal natural gas contains more than 90 mole % CH4.
Typical removal rates of contaminants (expressed as the amount in weight that is removed) are given in Table 2.
TABLE 2
Typical contaminants removal of the present invention
Contaminant
Typical Removal Rate
Method
Moisture
>99%
Condense and freeze
Siloxanes
>95%
Condense
Particulates (Dust)
>98%
Filtration and washing of
gas
Hydrocarbons > C5
>80%
Condense
Ammonia
Solubility: 89 g/100 cc
Washing (soluble in water)
Hydrogen Sulphide
Solubility: 437 g/cc
Washing (soluble in water)
Halides (Chlorine,
Washing (very soluble in
Fluorine)
water)
The gas treated in step (a) may subsequently be conducted through a re-polisher in step (b). The re-polisher is preferably either an activated coal absorber or a catalyst conversion unit, for instance using SOXSIA™ mentioned above. Suitable characteristics of activated coal are given in Table 3. By removing a large percentage of the contaminants in step (a) any trace levels of contaminants in the treated gas can be removed by a fraction of the previously required activated carbon.
TABLE 3
General characteristics of activated extruded carbon
Butane adsorption at
p/po = 0.42
22
g/100 g
p/po = 0.1
20
g/100 g
p/po = 0.01
17
g/100 g
Benzene adsorption at p/po = 0.1
32
g/100 g
Total surface area (BET)
1100
m 2 /g
Carbon tetrachloride activity
60
g/100 g
Apparent density
510
kg/m3
Ball-pan hardness
99
Particle size > 2.36 mm
99
mass-%
Ash content
5
mass-%
Moisture (as packed)
1
mass-%
Ignition temperature, above
450
° C.
Alternatively, an adsorbent/catalyst, such as SOXSIA™, or the like may be applied. Typically a catalyst with a particle diameter of 3 mm and length of 8 mm is used. The favourable adsorption properties result in high adsorption capacity and removal efficiency for contaminants present at moderate concentrations in gas flows. The extruded particle shape allows a low pressure drop over the filter. The catalyst/absorbent allows for conversion of sulphur compounds, in particular H 2 S into elementary sulphur and also for adsorption of other contaminants, such like siloxanes in the pores of the SOXSIA™ adsorbent.
The desulphering agent is preferably iron oxide, Fe 2 2O 3 , which allows for removal of H 2 S by the chemical reaction: Fe 2 O 3 +3H 2 S→Fe 2 S 3 +3 2 O. It may subsequently be reactivated using oxygen, e.g. from air by the reaction: 2Fe 2 S 3 +3O 2 →2Fe 2 O 3 +6S.
During reactivation, the elementary sulphur may be retained in the pores of the adsorbent. For reactivation, a small flow of oxygen comprising gas, such as air is contacted with the catalyst/adsorbent, e.g. by circulation though the catalyst/adsorbent bed. Since in general the reactivation reaction is exothermal, heat is produced. This heat will consequently evaporated the adsorbed siloxanes and other contaminants.
After reactivation, the performance of the catalyst/adsorbent may be reduced due to the fact that some sulphur may be retained. To remove the sulphur completely or almost completely, the catalyst/adsorbent can be heated to a temperature that is sufficient for elemental sulphur to melt, preferably in an inert gas, such as using nitrogen. Preferred temperatures are above 300° C.
Next, in step (c), the methane comprising stream (B) is cooled to a temperature which is sufficient to condensate CO 2 from said stream (B).
Deep-cooling of the gas mixture is typically attained through three steps. By reducing the temperature of the gas mixture down to approximately −60° C. the dew point of CO 2 is reached, and condensation of CO 2 appears. In these conditions, approximately 50% of the present CO 2 can be liquefied.
Using the Wobbe Index of the outlet gas (P) composition, the final temperature of the gas can be be controlled. At this final temperature the vapour/liquid equilibrium may be chosen such that it corresponds to the required Wobbe Index. This final temperature will preferably vary between −65° C. and −80° C., depending on the required gas composition. From FIG. 3 , “Isotherms of CH 4 /CO 2 binary”, it follows that the final temperature will decrease as the final mole fraction of CH 4 increases.
From FIG. 4 , “Phase diagram CH 4 /CO 2 binary”, it follows that reducing the temperature below −65° C. will result in formation of solid CO 2 .
Therefore, in a preferred embodiment, the final cooling will be attained using two parallel triple tube heat exchangers, wherein the first heat exchanger is cooling, while the other is defrosted, and visa versa. Using these alternating heat exchangers, a continuous gas flow may be created without interruption caused by freezing. It was found that it is very desirable to have two heat exchangers in parallel, because the problem of clogging as a result of processing solid/vapor/liquid CH 4 /CO 2 mixtures, which problem is referred to often in the prior art (see e.g. GB-A-1 565 615 and U.S. Pat. No. 4,681,612 mentioned hereinabove) can be avoided in accordance with the present invention. Thus by using an apparatus having two heat exchangers, the present invention is able can be operated within the solid/vapor/liquid region since solidification, which may lead to e.g. clogging of the system, is allowed in one of the heat exchangers as the other exchanger is defrosting. Thus the apparatus which is proved in one embodiment of the invention allows for less rigid and less stringent process control, which is of course very desirable.
Since the temperature of liquefied CO 2 in the final cooling section is lower than the temperature of liquefied CO 2 from the first cooling section, also the partial pressure may differ. Therefore the liquefied CO 2 from the final cooling section may be heated to the same temperature as the first cooling section using a pre-cooler for the incoming biogas. Finally it can be controlled that both liquefied CO 2 streams from first and final cooling section are at the same temperature and pressure and will be stored in the liquefied CO 2 storage tank. A schematic diagram for stage 3 of the GPP is given in FIG. 2 .
The efficiency of the system of the present invention is remarkably high. Loss of methane (CH 4 ) is less than 2% in comparison with techniques as pressure swing absorption and membrane technology which might result in about 15%-20% loss.
The advantages of the biogas treatment process that is the object of the present invention, noted following the performance of tests, may be summarized as follows.
Chilling the gas mixture to −25° C. will also lower the dew point of the gas to −25° C.; If the gas mixture is heated after chilling, which is the normal procedure, condensation will no longer appear downstream the system; The reduced activated carbon quantity saves both material and manpower/maintenance cost, as well cost related to the disposal of the activated carbon; Downstream piping does not require heat tracing or insulation, providing additional cost benefits; Another benefit is that some of lower boiling point contaminants (ammonia, hydrogen sulphide) and halides will be washed out of the gas as the moisture condenses; plus the solubility of these contaminants increases substantially at low temperatures; Removing all contaminants including 2%-4% mol water will increase the caloric value of the gas by approximately 3% resulting in more electricity production per Nm 3 of gas; Downstream (after step (a)) low-quality materials like SS304 or carbon steel can be used because condensation does not appear. This may also provide for a considerable cost benefit.
By way of example, the present invention will now described in further detail with reference to the non-limiting embodiments that are schematically represented in the accompanying FIG. 1 and FIG. 2 .
FIG. 1 is a diagram of the present invention. Referring to FIG. 1 , biogas is produced by the bacterial degradation of waste in a landfill site or of another mass of organic waste. Typically 30%-50% of the gas produced is CO 2 and a small amount (no more than a few percent) is other impurity gases, especially H 2 S, SO 2 , halogens and siloxanes and the remainder is methane. Although the concentration of the other impurity gases is relatively small the impact to machinery is large. Hydrogen sulphide (H 2 S) and halogens (F, Cl, Br, I) as well as halogen compositions tend to form acids which can corrode major components in the processing equipment. Also, traces of siloxanes, hydrogen sulphide, halogens and other minerals may reduce the performance and increase the maintenance of the gas engines that may be installed downstream the biogas production facility.
The biogas is drawn from the source and compressed to the required working pressure for CO 2 condensation. According to FIG. 3 , required working pressure to achieve 90 mole % CH 4 at a minimum temperature of −80° C. is 1000 kPa.
Next the compressed biogas is fed to a gas/gas heat exchanger where the incoming gas is pre-cooled using the product gas (P), that will be re-heated well above its dew point. From the gas/gas heat exchanger the gas passes through a cold coalescer which removes the appeared moisture. Moisture residue is separated and drained at the separation point.
Next, the gas flows to a heat exchanger (e.g. a triple tube gas/gas heat exchanger), which chills gas mixture to approximately −25° C. Chilling gas condenses moisture, siloxanes and most other contaminants. Up to 99% of moisture may be captured in the first step. As the moisture freezes, it traps the contaminants, thereby reducing the chance for carryover in the outgoing treated gas. To achieve a continuous process two heat exchangers may be installed, which operate in an alternating sequence, viz. when one heat exchanger is in operation the second heat exchanger unit is switched off in order to defrost the frozen gas mixture containing the captured contaminants. The alternating sequence is repeated vice versa to provide continuous and uninterrupted gas flow. The heat produced in the heat exchanger that is in cooling mode, may be used to heat the heat exchanger that is in defrosting mode.
Treated gas is drawn through a re-polisher at a gas temperature of −25° C. The re-polisher is preferably an absorber filled with SOXSIA™ catalyst. Next purified gas is further deep-cooled in step (c) which is illustrated in FIG. 2 .
Deep-cooling of the gas mixture is typically attained through three steps. By reducing the temperature of the gas mixture down to approximately 60° C. the dew point of CO 2 is achieved and condensation of CO 2 appears. In these conditions, approximately 50% of the CO 2 present can be liquefied.
Using the Wobbe Index of the outlet gas (P) composition, the final temperature of the gas may be controlled. At this final temperature the vapour/liquid equilibrium is such that it corresponds to the required Wobbe Index. This final temperature will vary between −65° C. and −80° C., depending on the required gas composition. From FIG. 3 it follows that the final temperature will decrease as the final mole fraction of CH 4 increases.
From FIG. 4 it follows that reducing the temperature below −65° C. will create solid formation of CO 2 .
Therefore the final cooling will be achieved using two parallel triple tube heat exchangers where the first heat exchanger is cooling, while the other is defrosted visa versa. Using these alternating heat exchangers, a continuous gas flow is created without interruption caused by freezing.
Since temperature of the liquefied CO 2 in the final cooling section is lower than the liquefied CO 2 from the first cooling section, also the partial pressure differs. Therefore the liquefied CO 2 from the final cooling section will be heated to the same temperature as the first cooling section using a pre-cooler for the incoming biogas. Finally both liquefied CO 2 streams form first and final cooling section are at the same temperature and pressure and will be stored in the liquefied CO 2 storage tank.
In order to avoid hydrate formation of CO 2 , CH 4 , H 2 S and/or other hydrate forming species, the temperature limits are controlled and the pressure loss over both cooling steps (a) and (c) are preferably monitored. In case pressure loss increases to a certain preset maximum value the exchangers of the respective step switch position and hydrate/solid H 2 O (step (a)) or CO 2 (step (c)) can be removed in the defrosting mode.
The driving force for achieving the required outlet composition is the (triple tube gas) heat exchanger in step (c) wherein liquid CO 2 from biogas is being evaporated in order to achieve the required CO 2 Vapour/Liquid equilibrium temperature (see FIG. 3 ). The equilibrium temperature and the feed conditions will determine the purity of the sellable gas. The equilibrium temperature control ensures fixed and stable Wobbe index of the sellable gas. The CO 2 used as refrigerant in this section can easily be recovered and subsequently offered to CO 2 users.
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The invention is directed to processes and apparatuses for gas treatment, in particular for the purification of methane rich gas streams, such as gas obtained from the conversion from organic matter (“biogas”). In accordance with the present invention there is provided an apparatus and a process for producing a purified methane comprising gas stream (P) from a methane containing gas stream (A), comprising the steps of: (a) pressurising said methane containing gas stream (A) and subsequently cooling it, whereby a stream comprising condensed contaminants (C) and a methane comprising stream (B) are obtained; (b) optionally feeding said methane comprising stream (B) to an adsorption unit and/or a catalytic conversion unit, whereby the concentration of contaminants in stream (B) is further decreased; and (c) cooling the methane comprising stream (B) to a temperature which is sufficient to condensate CO2 from said stream (B), whereby said purified methane comprising gas stream (P) is obtained.
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[0001] The present invention relates to a process for etching carbon fibers, in particular carbon nanofibers, and also the carbon nanofibers which can be obtained by this process and their use.
BACKGROUND OF THE INVENTION
[0002] Carbon fibers such as carbon nanofibers are promising materials for many possible applications, e.g. conductive and very strong composites, energy stores and converters, sensors, field emission displays and radiation sources and also nanosize semiconductor elements and testing points (Baughman, R. H. et al., Science 297:787-792 (2002)). Another promising application is catalysis using carbon nanofibers as catalysts or as supports for heterogeneous catalysts (de Jong, K. P. and Geus, J. W., Catal. Rev.-Sci. Eng. 42:481-510 (2000)) or as nanosize reactors for catalytic syntheses (Nhut, J. M. et al., Appl. Catal. A. 254:345-363 (2003)). It is frequently necessary to modify the surface either chemically or physically for the abovementioned applications. For example, complete dispersion of the nanofibers in a polymer matrix and the resulting strong interaction between fiber and matrix is advantageous in composites (Calvert, P., Nature 399:210-21 (1999)). When used as catalyst supports, foreign atoms have to be deposited on the nanofibers. Anchor points such as functional groups or defects are necessary for this purpose. To achieve this, the inert surface of the untreated (“as-grown”) nanofibers has to be modified (Xia, W. et al., Chem. Mater. 17:5737-5742 (2005)). For use in the sensor field, bonding of chemical groups or immobilization of a protein having specific recognition centers to/on the nanofibers is necessary. This is generally realized by production of functional surface groups or surface defects (Dai, H., Acc. Chem. Res. 35:1035-5742 (2002)).
[0003] Motivated by the promising possible applications, extensive studies on the surface modification and functionalization of carbon nanofibers have been carried out in the last 10 years. Among all these methods, the most intensive research has been carried out on covalent surface functionalization which is generally based on strong oxidants such as nitric acid, oxygen plasma, supercritical fluids, ozone and the like and, for example, subsequent side chain extension (Banerjee, S. et al., Adv. Mater. 17:17-29 (2005)). These oxidation methods usually increase the oxygen content of the surface, with visible physical modifications also being able to be achieved by appropriate selection of parameters. These physical changes are limited to two- or three-dimensional surface defects having unforeseeable structures in unknown positions. Under extreme conditions, for example a mixture of concentrated sulfuric acid and nitric acid, nanofibers are split into smaller fibrous units (Liu, J. et al., Science 280:1253-1256 (1998)). Identification of the surface defects remains a challenge because of the small dimensions and the curved surface of carbon nanofibers (Ishigami, M. et al., Phys. Rev. Lett. 93:196803/4 (2001)). Scanning tunneling microscopy (STM) is a very effective tool here (Osváth, Z. et al., Phys. Rev. B. 72:045429/1-045429/6 (2005)). Fan and coworkers have identified chemical surface defects by means of atomic force microscopy (AFM) using defect-sensitive oxidation with H 2 Se (Fan, Y. et al., Adv. Mater. 14:130-133 (2002)). In Xia, W. et al., Chem. Mater. 17:5737-5742 (2005), the alteration of the surface of carbon nanofibers is effected by deposition of cyclohexane on iron-laden carbon nanofibers. However, these secondary carbon nanofibers (tree-like structures composed of trunk and branches) are not functionalized and the surface modifications obtained cannot be used for loading with functional molecules.
[0004] The above problems apply analogously to carbon microfibers, e.g. carbon fibers produced from polyacrylonitrile (PAN) and composed of fiber bundles up to millimeter ranges, which are employed as continuous fibers in modern high-performance composites.
[0005] Despite the numerous efforts to modify the surface of carbon fibers such as carbon nanofibers, functional surface groups or surface defects have to the present time not been able to be introduced in a targeted manner by means of any of the abovementioned methods.
BRIEF DESCRIPTION OF THE INVENTION
[0006] Surprisingly, a localized etching technique by means of which surface defects can be produced at predetermined places on carbon fibers such as multiwalled carbon nanofibers (known as multiwalled carbon nanotubes, hereinafter referred to as “MWNT” or “nanofibers” for short). Etching is in this case based on gasification of carbon by means of water vapor
[0000]
[0000] with nanosize iron particles present on the nanofibers catalyzing the gasification. Etching occurs at the interface and is limited to the places on the carbon fibers where iron particles are present. Etching can easily be controlled by appropriate choice of the parameters for pretreatment (loading with iron, heating time, etc.) and the process parameters (reaction time, temperature, partial pressure of water, etc.). In this way, carbon fibers having spherical etching pits can be synthesized using inexpensive raw materials (water and iron) in an environmentally friendly process. In addition, the process produces hydrogen and carbon monoxide which are the main constituents of synthesis gas. The invention accordingly provides
(1) a process for etching carbon fibers, which comprises
(a) functionalization of the surface of the carbon fibers by oxidation, (b) deposition of metal particles on the functionalized surface, (c) etching of the surface by treatment with water vapor, (d) removal of the metal particles by acid treatment,
(2) etched carbon fibers which can be obtained by the process according to (1) and (3) the use of the etched carbon fibers according to (2) in composites, energy stores, as sensors, as adsorbents, supports for heterogeneous catalysts and as catalytically active material after additional oxygen functionalization.
[0014] The carbon fibers according to the present invention encompass carbon nanofibers and carbon microfibers, but are not restricted thereto.
BRIEF DESCRIPTION OF THE FIGURES
[0015] FIG. 1 : Two-dimensional schematic depiction of the four main steps in the etching process. The nanofibers were functionalized on the surface by means of concentrated nitric acid to increase the number of oxygen atoms. Iron from ferrocene as precursor was then deposited from the vapor phase. The subsequent etching was carried out using 1% by volume of water vapor in helium. The metal particles were finally removed by washing with 1M nitric acid at room temperature.
[0016] FIG. 2 : Schematic depiction of the apparatus for iron deposition (a) and water vapor etching of carbon nanofibers (b).
[0017] FIG. 3 : The consumption of water and the liberation of carbon monoxide during water vapor etching, recorded by on-line mass spectroscopy.
[0018] FIG. 4 : Scanning electron micrographs of the nanofibers after etching: (a) untreated, with the iron nanoparticles; (b) after removal of the iron nanoparticles by means of 1M nitric acid.
[0019] FIG. 5 : Transmission electron micrographs of the nanofibers after etching with water at 670° C. (a) untreated, with the iron nanoparticles; (b & c) after removal of the iron nanoparticles by washing with 1M nitric acid; (d) HR-TEM of a wall of a nanofiber destroyed by the etching process.
[0020] FIG. 6 : Powder diffraction patterns of the untreated and etched nanofibers.
[0021] FIG. 7 : Isotherms of the nitrogen physisorption measurements for untreated and etched nanofibers. The inset graph shows the pore radius distribution of the etched nanofibers.
DETAILED DESCRIPTION OF THE INVENTION
[0022] The carbon fibers according to the present invention are structures which can be obtained by polymerization of unsaturated hydrocarbon compounds. In a first preferred embodiment of the process (1), the carbon fibers are carbon nanofibers. These comprise carbon and can, for example, be produced from hydrocarbons by catalytic pyrolysis and are also obtainable from, for example, Applied Sciences Inc. (Cedarville, Ohio, USA) or Bayer MaterialScience. Such carbon nanofibers usually have an external diameter of from 50 to 500 nm, preferably about 100 nm, an internal diameter of from 10 to 100 nm, preferably about 50 nm, and a surface area of from 10 to 60 m 2 /g, preferably from 20 to 40 m 2 /g. As a result of the etching process of the invention, the specific surface area of the carbon nanofibers increases to from 90 to 100 m 2 /g.
[0023] In a second preferred embodiment of the process (1), the carbon fibers are microfibers. Such microfibers comprise, for example, carbon and are produced, for example, by pyrolysis of polyacrylonitrile fibers and can also be obtained from, for example, Zoltek Companies Inc. (St. Louis, USA) or Toho Tenax Europe GmbH. These microfibers have an external diameter of from 3 to 10 μm, preferably about 6 μm, and a surface area of less than 1 m 2 /g. As a result of the etching process of the invention, the specific surface area of the microfibers increases to from 5 to 50 m 2 /g.
[0024] In step (a) of the process of the invention, the surface of the carbon fibers is functionalized by oxidative treatment of the fibers. This can preferably be effected suddenly by heating with oxidizing acids or by oxygen plasma treatment. Particular preference is given to heating with nitric acid, e.g. with concentrated nitric acid.
[0025] In step (b) of the process of the invention, metal particles are applied to or deposited on the fibers which have been treated in step (a). These metal particles are preferably selected from among iron (Fe), cobalt (Co) and nickel (Ni), with Fe particles being particularly preferred. Preference is also given to from 1 to 20% by weight, preferably from 5 to 10% by weight, of metal, based on the total weight of the laden carbon nanofibers, being applied in this loading step. The application/deposition of the metal particles is preferably effected by contacting of the fibers with dissolved metal salts or metallocenes (preferably ferrocenes), in particular at a temperature of from 100 to 600° C., and subsequent reduction by means of hydrogen at a temperature of from 300 to 800° C., preferably about 500° C.
[0026] In step (c) of the process of the invention, the fibers doped with metal particles are etched. This is effected according to the invention by treatment with water vapor in a helium atmosphere, with the water vapor content of the helium atmosphere preferably being from 0.1 to 10% by volume, particularly preferably about 1% by volume. Preference is also given to the helium atmosphere containing from 1 to 20% by volume, preferably about 10% by volume, of H 2 in order to keep the metal catalyst active. Etching is preferably carried out at a temperature of from 500 to 800° C., particularly preferably above 600° C.
[0027] In step (d) of the process of the invention, the metal particles are removed. This is preferably achieved by treatment with an acid, in particular aqueous hydrochloric acid or a mixture of HNO 3 /H 2 SO 4 . The carbon fiber obtained in this way can be loaded with functional ligands at the etched positions in a subsequent step (e) as a function of the desired use. Thus, for example, use as catalyst requires loading with the metal atoms/particles required for this purpose.
[0028] The present invention is illustrated below for carbon nanofibers. However, this does not restrict the scope of protection of the patent.
[0029] A typical etching process is illustrated in FIG. 1 . The MWNTs (internal diameter: some tens of nm; external diameter: about 100 nm; Applied Sciences Inc., Ohio USA) were firstly treated under reflux in concentrated nitric acid for 2 hours and iron was then deposited from ferrocene. The deposition and the sintering of iron nanoparticles is described in detail in Xia, W. et al., Chem. Mater. 17:5737-5742 (2005). The iron loading in the present study varies in the range from 5 to 10% by weight and can be altered by variation of the amount of the ferrocene precursor. The iron-laden nanofibers were reduced and heat treated at 500° C. in hydrogen for 1 hour. Helium is passed through a saturator filled with water (room temperature) and water vapor (1% by volume) is in this way introduced into the reactor ( FIG. 2 ). Hydrogen (10% by volume) was used in order to keep the iron catalysts active. The formation of CO (m/e=28) and the consumption of H 2 O (m/e=18) were observed by on-line mass spectrometry at sample temperatures above 600° C. The reaction temperature correlates with the size of the iron particles deposited. A higher initial temperature is necessary for large catalyst particles; deactivation is very rapid for small particles and results in the reaction stopping. It has been found that the iron catalysts can be active for up to 2 hours, depending mainly on the particle size and the reaction temperature.
[0030] The removal of the iron particles from the surface of the carbon nanofibers can be carried out by means of aqueous hydrochloric acid or a mixture of HNO 3 and H 2 SO 4 , as described in Wue, P. et al., Surf. Interface Anal. 36:497-500 (2004).
[0031] The morphology of the nanofibers was examined by means of SEM. FIG. 4 a shows the nanofibers in the untreated state. The existence of nanosize iron oxide particles which have been embedded in the surface of the nanofibers in the etched samples can be observed ( FIG. 4 b ). The spherical etching pits are clearly visible after the iron particles have been removed by washing with acid ( FIG. 4 c ). The transmission electron micrograph shown in FIG. 5 a demonstrates the embedding of the iron nanoparticles due to the etching process. The surface roughness was increased considerably by etching, as the transmission electron micrographs after washing out of the iron nanoparticles show ( FIG. 5 b - c ). In addition, the damage to the wall of the nanofibers can be seen in the high-resolution TEM shown in FIG. 5 d. A spherical hole has been etched into the nanofiber, obviously by the outer walls being removed successively.
[0032] The etching over a short period of time results mainly in surface defects without any appreciable changes in the materials properties being observed. On the other hand, the materials properties can be altered significantly by lengthening the etching time. FIG. 6 shows the result of X-ray diffraction (XRD) on nanofibers which have been etched for more than one hour. Compared to the untreated nanofibers, the signal intensity is considerably reduced after etching. Although it is not appropriate to correlate the intensity directly with the crystallinity, a significant increase in disorder after etching can be deduced without doubt from highly reproducible XRD results. Relatively small mesopores were produced by etching, as can be shown by the nitrogen physisorption measurements ( FIG. 7 ). In the case of etched nanofibers, hysteresis between the adsorption and desorption branches of the isotherms was observed and a pore diameter of a few nanometers was deduced ( FIG. 7 ). Such small pores cannot be detected in untreated MWNTs which have virtually perfect parallel walls. As a consequence, the specific surface area of the nanofibers is increased from about 20˜40 m 2 /g to 90˜110 m 2 /g.
[0033] In summary, it can be said that mesoporous MWNTs having spherical etching pits can be produced in a targeted, local etching process which is both environmentally friendly and is based on advantageous raw materials (iron and water). In the innovative process, etching takes place at the surface of the nanofibers and is limited to the interface between the iron particles and the nanofibers. All parts of the nanofiber surface without iron particles are not altered by the etching process. The simple control and variation of the process parameters makes the etching process extremely flexible. Possible uses are in the field of polymer composites, catalysis and biosensors. We assume that the etching pits effectively reduce the surface mobility of deposited nanosize catalyst particles and thus enable the aggregation (sintering) which leads to deactivation of the catalysts to be avoided. In addition, it is expected that the increased surface roughness will be useful for the immobilization of the functional proteins in biosensors and will lead to significantly improved oxygen functionalization.
[0034] The invention is illustrated with the aid of the following examples. However, these examples do not restrict the subject matter claimed in any way.
EXAMPLES
Example 1
[0035] The iron-laden nanofibers (10% by weight; obtainable from Applied Sciences Inc., Cedarville, Ohio, USA) were reduced and heat treated at 500° C. in a mixture of hydrogen and helium (1:1, 100 ml min −1 STP) for one hour. A total gas stream of 100 ml min −1 STP having a hydrogen concentration of 10% by volume and a water concentration of 1% by volume was produced as follows: helium (32.3 ml min −1 STP) was passed through a saturator filled with water (room temperature). Hydrogen (10 ml min −1 STP) and additional helium (57.7 ml min −1 STP) were combined with the water-containing helium stream in the reactor upstream of the fixed bed. The hydrogen used (10% by volume) served to keep the iron catalyst active. Control of all gas streams was effected by on-line mass spectroscopy (MS). Since the water signal (m/e=18) was stationary after about 30 minutes, the reactor was heated from 500° C. to 670° C. at a heating rate of 20 K min −1 . The reaction commenced at about 600° C., as shown mass-spectroscopically by the formation of CO (m/e=28) and the consumption of H 2 O (m/e=18). After a further reaction time of about two hours, the reactor was cooled at 10 K min −1 to 450° C. under helium (100 ml min −1 STP). After a minimum hydrogen signal (m/e=2) had been reached after about 30 minutes, (50 ml min −1 STP) together with helium (50 ml min −1 STP) was introduced to remove carbon-containing deposits by oxidation. Mass-spectroscopic monitoring of the oxygen signal (m/e=32) showed that elimination of the carbon deposits was complete after about 5 minutes. The reactor was cooled to room temperature. The etched sample (FeO x /CNF) was washed with 1M HNO 3 at RT for one hour while stirring, subsequently filtered off and dried for the purpose of further characterization.
Example 2
[0036] When the iron loading in the first step is reduced to 5% by weight and all other parameters of Example 1 are kept constant, the reaction time is 1.5 h.
Example 3
[0037] When the maximum temperature in the third step is reduced from 670° C. to 650° C. while keeping all other parameters of Example 1 constant, the reaction time is 1 h.
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The present invention relates to a method for etching carbon fibers, in particular carbon nanofibers and to the carbon nanofibres obtainable by this method, and the use thereof.
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BACKGROUND OF THE INVENTION
In the field of high-speed printing devices which are especially suitable for use in connection with electronic data processing systems, the wire matrix type of printer has come into increasing use. In this type of printer, letters, numbers and symbols are formed from a series of dots produced by the impact of the ends of a plurality of wire elements on record media, most customarily in combination with an ink ribbon which provides the ink needed to produce a mark on the record medium being printed upon.
One problem which has arisen in connection with use of printers of the wire matrix type is that of fatigue breakage of the print wires and associated springs employed to return the wire to a non-printing position after a printing stroke. This breakage results from bending and vibration of the print wires caused by the high force employed to drive the wires over a short distance to impact upon the record medium being printed upon or the ink ribbon associated therewith. In order to reduce or eliminate such breakage, in some prior art structures, the individual print wires have been confined within tubes or coil springs anchored in the printer framework. However such structures have the disadvantages of increasing the parts and labor costs, and also tend to impede the movement of the printer wires by frictional engagement between the wires and the tubes. This, in turn, has led in some instances to further structural alterations of the printers to provide means for lubricating the wires within the tubes, thereby additionally increasing the cost and complexity of the assembly.
SUMMARY OF THE INVENTION
This invention relates to a printer of the matrix type, and more particularly relates to such a printer which includes means for dampening vibration and bending of the print elements to reduce or eliminate fatigue failure.
In accordance with one embodiment of the invention, a printing mechanism comprises frame means including at least two support members; at least one elongated printing element extending through and supported by said support members and capable of being driven in an axial direction to effect printing; driving means operatively connected to said printing element for axially driving said element; and at least one tubular element having a length less than the distance between adjacent support members, and being unattached to said support members and riding freely on said printing element to dampen undesired transverse movement and vibration thereof.
One advantage of the present invention is that dampening of the bending and vibration of the print elements is achieved without substantial frictional drag on the print elements which might be experienced if a guide tube fixedly secured to frame members of the printer were employed for each print element.
Another advantage of the present invention is that dampening means for the print elements are provided which are inexpensive both in terms of the cost of the parts and in terms of the cost of assembly.
It is accordingly an object of the present invention to provide a print head including elongated printing elements having vibration dampening means for the printing elements which are both inexpensive and effective in operation.
Another object is to provide a print head having elongated printing elements and also having vibration dampening means which do not impose a substantial frictional load on the print elements.
A further object is to provide a print head which is durable and reliable in operation.
With these and other objects, which will become apparent from the following description, in view, the invention includes certain novel features of construction and combinations of parts, one form or embodiment of which is hereinafter described with reference to the drawings which accompany and form a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view, taken along line 1--1 of FIG. 2, of a print head in accordance with the present invention;
FIG. 2 is a cross-sectional view, taken along line 2--2 of FIG. 1;
FIG. 3 is an elevation view, partly broken away, showing the frame, the elongated printing elements, and the dampening means, of the print head; and
FIG. 4 is an enlarged bottom view of the frame of FIG. 3, showing the printing end of the print head.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now particularly to FIGS. 1 and 2 of the drawings, a print head 10 of the wire matrix type is shown. This print head is similar in general configuration to the print head disclosed in U.S. Pat. No. 3,929,214, issued Dec. 30, 1975, to which reference may be had for a more detailed description of certain aspects of the print head structure.
A frame 12 is provided to support a plurality of elongated print elements or print wires 14, only two of which are shown, for purposes of simplification and ready understanding of the drawings. Each wire 14 has a cap 16, which may be made of plastic or other suitable material, attached to its impact-receiving end to enlarge the area of the impact-receiving surface. Each wire 14 also has a spring 18 disposed at its upper end, which exerts an upward force upon the cap 16 to resiliently bias the wire upwardly, as shown in FIGS. 1 and 3, relative to the frame 12. The spring 18 has been omitted from one of the wires of FIG. 1, in order that the cap 16 may be more clearly depicted.
The frame 12 includes three side walls 20, 22, and 24, a print end support member 26, two intermediate support members 28 and 30 positioned in grooves in the side walls 20 and 22, and an upper end support member 32 which is formed integral with the side walls 20, 22 and 24 of the frame 12. The members 26, 28, 30, and 32 constrain the various print wires 14 in predetermined paths, and accomplish the translation of the wires from a circular formation at the upper end as seen in FIG. 1 to a linear formation at the printing end. The translation is accomplished by passing each wire 14 through a separate hole 34 in the upper member 32, through similar holes in the members 24 and 22, and into a defined position within a bearing 36 in the print end support member 26, as shown in FIG. 4. The bearing 36 is of a material which resists wear, has a low co-efficient of friction, and has a low co-efficient of thermal expansion.
A pair of mounting flanges 38 and 40 extend laterally from the upper ends of side walls 20 and 22. The frame 12 is circular in cross-sectional shape above the flanges 38, 40 as seen in FIG. 1, and terminates in the upper end support member 32, which is of circular configuration. An apertured post 42 extends from the member 32 and provides means for assembling the driving means for the wires 14 to the frame 12, as will subsequently be described in greater detail.
As shown in FIGS. 1 and 2, a plate 44 is provided with a central aperture 46 and is secured to the flanges 38, 40 on the frame 12 by suitable fastening means 48. The circular portion of the frame 12 extends through the aperture 46. A plurality of holes 50 are provided in the plate 44 for mounting a corresponding plurality, nine in the illustrated embodiment, of actuating means for the wire printing elements 14.
A coil 52, a center pole 54, an "L" shaped outer pole 56 and an armature 58 form the electromagnetic actuating means used in the print head. An armature shim 59 spaces the armatures 58 away from the poles 54 for the purposes of effecting faster armature release. A bore 60 is provided in the horizontal leg of the "L" shaped outer pole 56 for receiving in forced-fit relationship the lower extremity of the center pole 54.
A unitary connector 62 is mounted by means of a screw 64 and a washer 66 to the post 42 of the frame 12. The connector 62 has a circular central portion 68 with an annular groove 70 provided in its bottom surface. An O-ring 72 is inserted in the groove 70 to act as a shock absorber and to provide a reference surface for the cap 16 of the print wire 14 striking the end of the armature 58. Nine arms 74 are formed integral with the central portion 68 of the connector 62 and extend therefrom. Each arm 74 has associated with it a first armature receiving structure 76 and a second armature receiving structure 78. One end of each armature 58 is received and held in place by the structure 76 and the other end of each armature is received and guided by the structure 78. With the connector 62 installed in the position shown, the arms 74 apply forces to the cantilevered distal ends of the armatures, causing their print wire impacting ends to rotate about the fulcrum formed by the top edge of the pole 56 and upwardly into engagement with the O-ring 72. The caps 16 associated with the print wires 14 are maintained in contact with the ends of the armature 58 by means of the forces applied by the springs 18.
As discussed in greater detail in the previously-cited U.S. Pat. No. 3,929,214, the unitary connector 62 serves a number of functions in the assembly and operation of the print head 10, including retaining the armatures 58 in proper relationship to the remainder of the structure, acting as a biasing means for the armatures, providing means for adjusting the air gap between the armatures 58 and corresponding center poles 52, forming a reference surface for the armatures 58 and print wire caps 16, to assure that all actuated print wires 14 impact the record medium at substantially the same time during a printing cycle, and, by means of the O-ring 72, absorbing energy from the armatures 58 and the print wires 14 on return motion after actuation.
As is also described in greater detail in the previously-mentioned U.S. Pat. No. 3,929,214, characters such as numbers, letters or symbols are generated by the print head by a sequence of print cycles. Selective actuation of predetermined combinations of print wires 14 through energization of their corresponding coils 52 during each cycle results in the formation of the desired character on the record medium, with the print head being shifted one position with respect to the record medium after each cycle to be properly located for the next printing cycle.
When a coil 52 is energized, a magnetic flux is created which causes armature 58 to be drawn into contact with center pole 54. The movement of armature 58 transmits energy into print wire 14, causing it to move in an axial direction in the frame 12. The force imparted into the wire 14 causes it to move against the spring 18 and its inertia causes it to continue to move downwardly out of contact with the armature 58 after said armature bottoms out against the center pole 54. The impact-delivering end of the print wire 14 extends beyond bearing 36 and strikes the record medium, causing a dot to be imprinted. The energy stored in the moving print wire 14 is partially absorbed by the impacted record medium and partially returned to the print wire 14, aiding the spring 18 in returning the print wire 14 to its rest position.
At approximately the same time that the print wire 14 is impacting the record medium, the coil 52 is deenergized. The moment exerted on the armature 58 by the arm 74 causes it to rotate away from the center pole 54 and to return into contact with the O-ring 72.
The structure which has been described to this point is conventional and provides an operable print head of the wire matrix type. However extended use of print heads of this type has resulted in problems of breakage of print wires 14 and springs 18 by fatigue failure.
The print wires 14 are small in diameter in order to produce proper character line width, a typical diameter being 0.014 inches. Print wire length is relatively long (typically three inches), in order to enable the print wires to be fanned out from their tight linear pattern at the bearing 36 to the larger circular pattern required to coact with the armatures 58. Due to the large ratio of wire length to wire diameter, and the fact that a relatively large impact force (approximately 4.5 pounds) is required to print, the wire 14 has a tendency to buckle. This tendency can be reduced by the addition of transverse supporting members along the length of the wire. As has been previously noted, some matrix print heads also employ anchored tubes or coil springs as supports, in order to further reduce the likelihood of buckling of the print wire.
In the present structure, a series of simple supports 28, 30 and 32 are spaced at intervals along the wire. However wire buckle still tends to take place between the supports. At the usual rapid actuation rate (typically 650 actuations per second), the buckling rate produces vibration. Over a typical matrix print head life of 75 million characters at an average of 2.2 dots per wire for each character, the print wire will be actuated 165 million times. This is well beyond the typical number of stress cycles for most structural members undergoing fatigue loads.
Wire failure due to vibration fatigue loads is dependent upon the stress induced in the wire. If the stress is low (below the fatigue limit) the wire will last an indefinite number of stress cycles. If the stress is high (above the fatigue limit) the wire will fail in a finite number of cycles. The stress is directly proportional to the radius of curvature (the bow in the wire during vibration). A smaller radius of curvature produces a tighter bow and higher stress.
To reduce wire breakage, the stress incurred during vibration must be lowered. This means increasing the radius of curvature by reducing the distance the wires move radially during vibration. The present invention reduces wire radial motion by adding dampening tubes, such as the tubes 80 shown in FIGS. 1, 2 and 3, to the wire 14 between the fixed supports, such as the supports 28, 30 and 32.
The tubes 80 fit loosely upon the wires 14 and are free to move radially with respect to the print wires as well as moving axially with the print wire as it is actuated, between the adjacent support members, such as between the support members 28 and 30, and between the support members 30 and 32. A tubular member may be placed on each wire between each set of support members, as appropriate.
It will be noted in FIG. 1 that no tube is shown between the end member 26 and the first support member 28. This is because in this portion of the frame of the illustrated embodiment, the wires are spaced quite close to one another, so that the tubes would not fit readily therein. Also the bearing 36 of the end member 26 extends upwardly into the space between the side walls 20, 22, as shown in FIG. 1, thus reducing the unsupported distance between support members of the wires 14.
Since the range of axial freedom of the movement of the tube 80 on the wire 14 is much longer than the wire activating motion initiated by the coil 52 and the armature 58, most drag friction is eliminated between the wire 14 and the tubes 80. It has been found that the dampening tubes 80 effectively reduce wire radial motion well below the point which induces critical stress that leads to fatigue failure.
The tubes 80 may be of any suitable material, either flexible or rigid. Two materials which have been successfully used in actual tests of the device are polytetrafluoroethylene resin and fluorocarbon resin.
Typical dimensions of the tubular members 80 which have been found to be suitable for use in connection with a print wire having a diameter of 0.014 inches and a length of 3 inches are a length of 0.50 inches plus or minus 0.040 inch tolerance, an inside diameter of 0.027 inches with a tolerance of plus or minus 0.007 inches, an outside diameter of 0.051 inches with a tolerance of plus or minus 0.004 inches. The tube may be of circular cross-sectional configuration, or may alternatively be of an oval configuration, as shown in FIG. 2.
A mass ratio which has been found to be successful is approximately 17 to 1; that is, the mass of the tubular element positioned on a wire 14 is approximately 17 times the mass of the wire 14 between adjacent support members. However this is not critical, and a wide range of mass ratios may be used.
In one length ratio which has been found to be successful, the length of the tubular members is slightly greater than half the distance between adjacent support members. This avoids interference between ends of adjacent tube members which might otherwise lock against each other during operation. However, the exact length ratio is not critical and a wide range of length ratios can be used, including tube lengths which are less than half the distance between adjacent support members. The mass of the tubular member can be adjusted by change in material or inside and outside diameter, if desired, to compensate for changes in tube length, while still maintaining the desired dampening function.
While the form of the invention shown and described herein is admirably adapted to fulfill the objects primarily stated, it is to be understood that it is not intended to confine the invention to the form or embodiment disclosed herein, for it is susceptible of embodiment in various other forms within the scope of the appended claims.
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In a matrix print head, a plurality of elongated printing elements, mounted in a frame, are driven axially by electromagnetic means to effect printing on record media positioned adjacent to the printing ends of the printing elements. Freely riding tubular elements are placed on the printing elements between support members forming part of the frame, in order to dampen the bending and vibration of the printing elements, and thus reduce or eliminate consequent fatigue failure.
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TECHNICAL FIELD OF THE INVENTION
[0001] The present invention concerns a method to be used for feeding at adjustable speed of an optical fibre cable into a pipeline/duct, and an arrangement devised for adjustable feeding of an optical fibre cable into the same. The feeding arrangement and method are primarily intended to be used for installations of optical fibre cables in pipeline systems located outdoors or between residential units and a central unit, such as between several apartments in an apartment building and a central coupling unit located in the house's cellar or similar.
DESCRIPTION OF RELATED ART
[0002] It has been known for some time that optical fibres or optical fibre cables can be blown or sucked into pipelines/ducts, either by creating overpressure by means of compressed air supply so that the optical fibre or optical fibre cable is blown into the pipeline, or by creating under-pressure at the end of the pipeline/duct, so that the optical fibre or the optical fibre cable is sucked into it.
SUMMARY OF THE INVENTION
[0003] In order to simplify the handling of optical fibre cables in connection with their feed into pipelines/ducts and to ensure that they are not exposed to undesirable pressure during the feeding process, which could result in the bending or breaking of the cables during this process, a feeding device located in the feeding mechanism has been supplied with a friction safety clutch which regulates the feed of the optical fibre cable when feed resistance increases. For additional regulation of the advancement of the optical fibre cable the feeding mechanism can be regulated by adjusting the air stream and/or the rotation speed of the feeding wheel. To further facilitate the operation of the feeding arrangement it has been designed as a hand-tool which needs to be connected to just one or more energy sources.
[0004] The invention is described below in more detail with the help of a proposed method of execution and with reference to the enclosed pages containing drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIGS. 1-3 show different views of the feeding device in accordance with the invention.
[0006] FIG. 4 shows the feeding device in perspective.
[0007] FIG. 5 shows the feeding device when disassembled.
[0008] FIGS. 4 and 5 provide details of how friction safety clutches can be arranged in relation to the feeding device.
DETAILED DESCRIPTION OF EMBODIMENTS
[0009] FIGS. 1-5 show how a feeding device can be constructed in accordance with the invention. The feeding device consists of a handgrip unit 1 containing a battery 2 and of a feeding system for optical fibre cables. The feeding arrangement consists in turn of a lower part 3 and an upper part 4 connected with each other by a guide bar 5 which is further equipped with an adjustable positioning screw 6 . With the help of the positioning screw 6 the distance between the upper part and the lower part can be regulated, so that the optical fibre cable can be placed correctly between the upper and the lower part when open, and when the two parts are brought together it will find itself in a groove 7 between the upper part and the lower part. The cross-section of the groove has been designed in such a way as to be able to hold a maximum of the cross-sectional area of the optical fibre cable. At the front of the upper and lower parts removable extension units 8 , 9 of suitable material have been fastened, which form together a hollow space 10 of a circular cross-section, for example, into which the end of a pipeline/duct can be entered, and through which the optical fibre cable is fed. Adjacent to the removable extension units is a space 11 for compressed air to be supplied for feeding the optical fibre cable into the pipeline. The lower section of this space is connected to a compressor 12 by means of an adjustment screw 13 for regulation of the supply of compressed air. The lower section is further connected to a handgrip unit 1 which can be designed like a pistol-type handle, containing a trigger 14 for the regulation of the number of revolutions of the engine 15 pushing the optical fibre cable forward. In addition to the regulator of the rotational frequency the section also contains a switch for changing the direction of the feed and a resetting device. The engine 15 is fastened to the lower part, and its driving axle 16 operates through a friction safety clutch 17 upon a moving coil 18 . The engine can be either electrically driven or it may be powered by compressed air. Electric operation can be provided by means of a rechargeable battery in the battery component 2 fastened to the handgrip's lower part 1 , or it may be connected to an external power supply via the rotational frequency regulator. When using the electric engine only, the optical fibre cable can be fed into the pipeline without any supply of compressed air to the extension units. When the engine is operated by compressed air, its compressor can be connected to the compressor used for the feeding of the optical fibre into the pipeline. The friction safety clutch 17 ensures controlled forward feed of the optical fibre cable due to the fact that at constant rotation of the engine and increased resistance felt by the optical fibre cable during its forward feed into the pipeline the moving coil will skid in the opposite direction to the driving axle, preventing the cable from being exposed to forces going in the opposite direction, which could result in the bending or breaking of the optical fibre cable in the feed area. By further providing the clutch with a possibility of regulation, a suitable safety level can be achieved for the forward-feed of the optical fibre cable. Thanks to the flexibility provided by the friction safety clutch, the force of the forward motion of the optical fibre cable can be regulated, depending on the resistance encountered in the pipeline, and the forward feed of the cable can thus be optimised.
[0010] The friction safety clutch 17 may consist of two circular contact surfaces 19 , 20 made of low-friction material, operating between the end of the driving axle 16 and the moving coil 18 made of metal, as well as between the said moving coil and an external plate ( 21 ), which is connected to the driving axle's end by means of adjustment screws 22 (see FIG. 6 ). The contact surfaces can thus be pressed against the moving coil with controlled force. If the feed of the optical fibre cable is obstructed in the pipeline, the contact surfaces of the friction safety clutch will start skidding against the moving coil, impeding its movement, so that the cable will not be pushed forward at the risk of being damaged. The friction safety clutch 17 may also consist of a moving coil 23 made of low-friction material, operating between the driving axle's end 16 and an external, spring-loaded 24 plate 25 made of, for example, metal. The force exerted by the spring can be regulated by means of a screw 26 in order to attain a desirable degree of friction by the clutch, thus preventing damage of the optical fibre cable during its forward feed into the pipeline.
[0011] The upper part contains further a spool holding device 27 , 28 with a spool support 29 on which a spool with an optical fibre cable can be fastened. The holding device for the spool arm has been designed in such a way that the position of the spool arm can be adjusted as desired. The upper part contains also a revolution counter 30 . With the help of the rev. counter the number of revolutions may be counted, or the length of the optical fibre cable fed into the pipeline measured by means of a measuring wheel 31 which is turned by the running optical fibre cable being fed into the pipeline. The measuring wheel can be spring-loaded, so that the pressure of the optical fibre cable which is being fed into the pipeline can be regulated, which helps to ensure that the cable advances correctly. The measuring wheel should preferably be made conspicuous and contain some sort of marking, so that the wheel's rotations can be observed, which is of great use to the user of the installation device. This can be done by providing a transparent lock 32 for the measuring wheel, ensuring its protection and visibility of its rotations. The user will thus be able to see whether the measuring wheel is rotating or not during the forward feed of the optical fibre cable by the moving coil, which is why it is a good idea to provide also the moving coil with some visible marking so that its rotations can be observed. This can be done by supplying a transparent lock 33 for the moving coil so that it can be protected and visible.
[0012] The installation device may either be held by hand or it may be placed on a tripod. A roll of optical fibre cable is placed on the spool arm and one end of the cable is introduced into the groove space between the upper and the lower part. To regulate the distance between the upper and the lower part a positioning screw is used for the raising or lowering of the upper part in relation to the lower part. When the two parts are brought together the measuring wheel will press the optical fibre towards the moving coil with the help of the spring. The optical fibre cable is further led through the interacting removable extension units, and its one end is stuck into a pipeline which has been placed in the extension units. When the engine is started and compressed air is supplied, the optical fibre cable will be fed into the pipeline. Depending on the feed requirements the positioning screws are adjusted in a suitable way, and an operator may monitor the feed.
[0013] When a tripod is used, the installation device can be manoeuvred from a distance with a remote control 34 . Once suitable air supply and a desirable degree of friction has been ensured with the help of the adjustment screws, the installation device placed on a tripod may easily be manoeuvred by means of the remote control, and the operator has more time to watch over and regulate the forward feed of the cables. The invention is, naturally, not limited to the above-described method of execution illustrated in the drawings, and can be modified within the framework of the attached patent claims.
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The present invention concerns a procedure and a system for feeding optical fibre cables into a pipeline with the help of an installation device at adjustable speed. In order to prevent damage during the advancement of the optical fibre cable the engine ( 15 ) of the installation device has been supplied with a friction safety clutch ( 17 ) exerting pressure on a moving coil ( 18, 23 ).
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to a corresponding provisional application U.S. Ser. No. 60/531,057, filed Dec. 18, 2003 in the names of the applicants of this application.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates generally to sink drains and, more specifically, to a device capable of deodorizing a sink drain area and/or removing clogs inside the sink drain.
[0004] 2. Description of Prior Art
[0005] Many sinks have been equipped with a garbage disposal unit. The garbage disposal unit grinds large food and waste particles into smaller particles that are then diverted into the drain pipe. The garbage disposal unit, however, may not be able to divert all of the waste particles, dirt, oil, and grease into the drain pipe. Build-up of bacteria, foul odors, and clogs may then begin to develop in the sink drain due to the dirt, oil, grease, and food particles that may have become trapped within it. Additionally, sink drains without a garbage disposal unit also tend to accumulate food particles which can cause a build-up of bacteria, causing both a foul odor as well as drain clogs.
[0006] One way by which people have attempted to combat the development of bacterial build-up and odors is by using antibacterial and deodorizing sprays. Although the sprays may eliminate some of the bacteria and the odors, they are easily washed away with the liquids poured into the drain.
[0007] Another way that people, especially those within the food process industry, have attempted to combat bacterial build-up and odors is to insert a drain sanitizing article into the drain. U.S. Pat. No. 6,197,321 issued to Richter et al. discloses a sanitizing article housing preferably molded with a handle as a one piece unit. The handle traverses and partially obstructs the inner opening of the housing so as to allow the handle to rest on a stand pipe which projects from a drain.
[0008] A problem arises, however, when this sanitizing article is placed within a sink equipped with a garbage disposal unit. Because the handle traverses the inner opening of the housing, a user is limited to the size and the type of debris that he/she wishes to place into the garbage disposal unit. The user would only be able to place debris capable of passing through the spaces unimpeded by the handle into the garbage disposal unit. And if the user were to wash a long pasta noodle or other similarly shaped debris down the drain opening, the noodle could get caught on the handle.
[0009] Furthermore, U.S. Pat. No. 4,318,193 issued to Bayer et al. discloses a flexible deodorant ring holder. The Bayer et al. device comprises a flexible arcuate shaped holder formed by a flexible arcuate outer rim, a plurality of radially extending rib members, and a flexible arcuate inner rim. The device therefore has an adjustable outside diameter for holding a rigid deodorant ring having a fixed outside diameter.
[0010] The configuration of the Bayer et al. device, however, would actually contribute to the problem of odors rather than solve it. Particularly, food particles and other debris may become lodged between or within the rib members of the flexible holder. Not only will the trapped food particles and debris cause odors, but they are also unpleasant to the eye. Furthermore, the flexible holder obstructs a substantial portion of the sink opening, thereby limiting the size and the type of debris that a user may wish to place into the underlying garbage disposal unit. Again, the user would only be able to place debris capable of passing through the spaces unimpeded by the rib members of the flexible holder into the garbage disposal unit. And if the user were to wash a long pasta noodle or other similarly shaped debris down the drain opening, the noodle could get caught on the flexible rib members of the flexible holder.
[0011] Therefore a need existed to provide a device for deodorizing a sink drain that allows the sink drain to remain substantially entirely open. Preferably, the device would remove sink drain clogs. Further preferably, the device would both deodorize the sink drain and remove sink drain clogs. Still further preferably, the device would have a wear indicator to signal the user when a new device is needed.
SUMMARY OF THE INVENTION
[0012] It is an object of the present invention to provide a device for deodorizing a sink drain and method therefor that allows the sink drain to remain substantially entirely open.
[0013] It is a further object of the present invention to provide a device for deodorizing a sink drain and method therefor that removes sink drain clogs.
[0014] It is a further object of the present invention to provide a device for deodorizing a sink drain and method therefor that both deodorizes the sink drain and removes sink drain clogs.
[0015] It is a still further object of the present invention to provide a device for deodorizing a sink drain and method therefor that employs a wear indicator to signal a user when a new device is needed.
BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] In accordance with one embodiment of the present invention, a device for deodorizing a sink drain is disclosed. The device for deodorizing a sink drain comprises at least one deodorizing ring, the at least one deodorizing ring being dimensioned to be substantially flush with an interior wall of the sink drain while at the same time defining an aperture dimensioned to allow the sink drain to remain substantially entirely open.
[0017] In accordance with another embodiment of the present invention, a device for deodorizing a sink drain is disclosed. The device for deodorizing a sink drain comprises at least one deodorizing ring, the at least one deodorizing ring being dimensioned to be coupled proximate an exterior portion of the sink drain while at the same time defining an aperture dimensioned to allow the sink drain to remain substantially entirely open.
[0018] In accordance with still another embodiment of the present invention, a method for deodorizing a sink drain is disclosed. The method for deodorizing a sink drain comprises, in combination, the steps of providing at least one deodorizing ring, the at least one deodorizing ring having a deodorizing agent and defining an aperture dimensioned to allow the sink drain to remain substantially entirely open, and positioning the at least one deodorizing ring such that the at least one deodorizing ring is substantially flush with an interior wall of the sink drain.
[0019] In accordance with yet another embodiment of the present invention, a method for removing clogs from a sink drain is disclosed. The method for removing clogs from a sink drain comprises, in combination, the steps of providing at least one deodorizing ring, the at least one deodorizing ring having a clog removing agent and defining an aperture dimensioned to allow the sink drain to remain substantially entirely open, and positioning the at least one deodorizing ring such that the at least one deodorizing ring is substantially flush with an interior wall of the sink drain.
[0020] In accordance with yet another embodiment of the present invention, a method for deodorizing a sink drain is disclosed. The method for deodorizing a sink drain comprises, in combination, the steps of providing at least one deodorizing ring, the at least one deodorizing ring containing a deodorizing agent being dimensioned to be coupled proximate an exterior portion of the sink drain while at the same time defining an aperture dimensioned to allow the sink drain to remain substantially entirely open, providing a refillable tray, the at least one refillable tray being dimensioned to house the at least one deodorizing ring, providing a plurality of legs having a first end and a second end, the first end of each leg being coupled to a portion of the refillable tray and the second end of each leg extending substantially downwardly from the at least one refillable tray, inserting the at least one deodorizing ring into the at least one refillable tray, and coupling the second end of each leg of the refillable tray to the sink drain so that the at least one deodorizing ring is supported above the sink drain.
[0021] The foregoing and other objects, features, and advantages of the invention will be apparent from the following, more particular, description of the preferred embodiments of the invention, as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a perspective view of a first embodiment of the device for deodorizing a sink drain consistent with the present invention. The first embodiment comprises a deodorizing ring.
[0023] FIG. 2 is a perspective cross-sectional view of the device of FIG. 1 being placed into a sink drain such that an outer surface of the device directly abuts an interior wall of the sink drain.
[0024] FIG. 3 is a top view of the device of FIG. 1 shown in use with the sink drain.
[0025] FIG. 4 is a perspective view of a second embodiment of a device for deodorizing a sink drain consistent with the present invention. The second embodiment comprises a refillable tray dimensioned to house at least one deodorizing ring.
[0026] FIG. 5 is a perspective view of the device of FIG. 4 having three deodorizing rings.
[0027] FIG. 6 is a perspective cross-sectional view of the device of FIG. 4 being placed into a sink drain such that an outer surface of the device directly abuts the interior wall of the sink drain.
[0028] FIG. 7 is a perspective view of a third embodiment of a device for deodorizing a sink drain consistent with the present invention. The third embodiment comprises a flexible crescent-shaped deodorizing ring. The flexible crescent-shaped deodorizing ring is shown in a contracted position.
[0029] FIG. 8 is a perspective view of a fourth embodiment of a device consistent with the present invention. The fourth embodiment comprises a hinged crescent-shaped deodorizing ring. The hinged crescent-shaped deodorizing ring is shown in a contracted position.
[0030] FIG. 9 is a perspective cross-sectional view of a fifth embodiment of a device for deodorizing a sink drain consistent with the present invention. The fifth embodiment comprises a flexible crescent-shaped refillable tray dimensioned to house at least one deodorizing ring. The device is shown as being squeezed and placed into a sink drain such that an outer surface of the device directly abuts the interior wall of the sink drain. A deodorizing ring is also shown being placed within the flexible crescent-shaped refillable tray.
[0031] FIG. 10 is a perspective view of a sixth embodiment of a device for deodorizing a sink drain consistent with the present invention. The sixth embodiment comprises a hinged crescent-shaped refillable tray dimensioned to house at least one deodorizing ring. The device is shown in a contracted position and three deodorizing rings are shown being placed within the hinged crescent-shaped refillable tray.
[0032] FIG. 11 is a perspective view of the hinged crescent-shaped deodorizing ring of FIG. 8 being placed within the hinged crescent-shaped refillable tray of FIG. 10 . Both the hinged crescent-shaped deodorizing ring and the hinged crescent-shaped refillable tray are shown in a contracted position.
[0033] FIG. 12 is a top view of the device of FIG. 7 in use with a sink drain.
[0034] FIG. 13 is a perspective view of a seventh embodiment of a device for deodorizing a sink drain consistent with the present invention. The seventh embodiment comprises a deodorizing ring having legs dimensioned to support the deodorizing ring above the sink drain.
[0035] FIG. 14 is a top view of the device of FIG. 13 shown in use with a sink drain.
[0036] FIG. 15 is a perspective view of an eighth embodiment of a device for deodorizing a sink drain consistent with the present invention. The eighth embodiment comprises a refillable tray dimensioned to house at least one deodorizing ring and having legs dimensioned to support the refillable tray above the sink drain. A deodorizing ring is also shown being placed within the refillable tray.
[0037] FIG. 16 is a perspective view of the device of FIG. 15 being placed above the sink drain. A deodorizing ring is also shown being placed within the refillable tray.
[0038] FIG. 17 is a perspective view of a wear indicator shown integrally coupled to a deodorizing ring. The wear indicator is shown as being a color that fades as the deodorizing ring is diminished by use.
[0039] FIG. 18 is a perspective view of a wear indicator shown integrally coupled to a refillable tray. The wear indicator is shown as being a color that fades as the deodorizing ring is diminished by use.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0040] The novel features believed characteristic of the invention are set forth in the appended claims. The invention will best be understood by reference to the following detailed description of illustrated embodiments when read in conjunction with the accompanying drawings, wherein like reference numerals and symbols represent like elements.
[0041] Referring to FIGS. 1-16 , a device for deodorizing a sink drain, hereinafter device for deodorizing a sink drain 10 , is disclosed. The device for deodorizing a sink drain 10 comprises at least one deodorizing ring 20 . As shown in FIGS. 1-3 , 7 , 8 , and 12 - 14 , the device for deodorizing a sink drain 10 may comprise at least one deodorizing ring 20 , or as shown in FIGS. 4-6 , 9 - 11 , 15 , and 16 , the device for deodorizing a sink drain 10 may further comprise a refillable tray 40 dimensioned to house the at least one deodorizing ring 20 . Although FIGS. 4-6 and FIG. 10 show the refillable tray 40 as housing up to three deodorizing rings 20 , it should be clearly understood that substantial benefit may be derived from the refillable tray 40 being dimensioned to house any number of deodorizing rings 20 so long as the refillable tray 40 is dimensioned to fit the sink drain 12 .
[0042] Preferably, the device for deodorizing a sink drain 10 will have an outer diameter of between 8 cm and 10 cm, an inner diameter of between 7 cm and 9 cm, and a width of between 0.5 cm and 2.5 cm. Although these dimensions are preferred, it should be clearly understood that substantial benefit may be derived from alternate dimensions, provided that the device for deodorizing a sink drain 10 is dimensioned to fit a sink drain 12 and is dimensioned to allow the sink drain 12 to remain substantially entirely open. It should also be understood that although it is preferable that the device for deodorizing a sink drain 10 be used with a standard-sized kitchen sink drain 12 , substantial benefit could be derived from alternative dimensions, even those that deviate substantially from the preferred dimensions in either direction, in order to use the device for deodorizing a sink drain 10 in sink drains 12 of varying sizes (e.g., bathroom sink drains, large industrial kitchen sink drains, etc.).
[0043] Referring now to FIGS. 1-12 , the device for deodorizing a sink drain 10 may be dimensioned to be substantially flush with an interior wall 14 of the sink drain 12 . Referring to FIGS. 1-3 , 7 , 8 , and 12 , the deodorizing ring 20 may be dimensioned such that an outer surface 39 (see FIGS. 1, 7 , and 8 ) of the deodorizing ring 20 directly abuts the interior wall 14 of the sink drain 12 . Similarly, as shown in FIGS. 4-6 and 9 - 11 , the deodorizing ring 20 may be housed within a refillable tray 40 dimensioned such that an outer surface 59 of the refillable tray 40 directly abuts the interior wall 14 of the sink drain 12 .
[0044] The deodorizing ring 20 a (referred to generically as deodorizing ring 20 ) shown in FIGS. 1-5 , 9 , and 15 and the refillable tray 40 a shown in FIGS. 4-6 (referred to generically as refillable tray 40 ) may have a substantially circular configuration. Alternatively, FIGS. 7-12 show deodorizing rings 20 and refillable trays 40 that are substantially crescent-shaped and that have outer diameters substantially larger than the inner diameter of the sink drain 12 .
[0045] For example, FIGS. 7 and 12 disclose a substantially flexible crescent-shaped deodorizing ring 20 b having a first grip end 22 a (referred to generically as grip end 22 ) and a second grip end 22 b (referred to generically as grip end 22 ). Similarly, FIG. 9 discloses a substantially flexible crescent-shaped refillable tray 40 b having a first grip end 42 a (referred to generically as grip end 42 )(not shown) and a second grip end 42 b (referred to generically as grip end 42 )(not shown). When inserting the deodorizing ring 20 b or the refillable tray 40 b into the sink drain 12 , the grip ends 22 of the deodorizing ring 20 b or the grip ends 42 of the refillable tray 40 b may be squeezed together, thereby causing the deodorizing ring 20 b or the refillable tray 40 b to contract. And by releasing the grip ends 22 of the deodorizing ring 20 b or the grip ends 42 of the refillable tray 40 b , the deodorizing ring 20 b or the refillable tray 40 b will expand and will be held in place within the sink drain 12 .
[0046] As a further example, FIG. 8 discloses a hinged crescent-shaped deodorizing ring 20 c having a first portion 26 and a second portion 30 . Both the first portion 26 and the second portion 30 have a hinge end 28 coupled to a hinge 24 . Both the first portion 26 and the second portion 30 also have a grip end 22 which, when squeezed together, cause the deodorizing ring 20 c to contract. While contracted, the deodorizing ring 20 c may be inserted into the sink drain 12 . Upon spreading apart or releasing the grip ends 22 , the deodorizing ring 20 c will expand and be held in place within the sink drain 12 .
[0047] Similarly, FIGS. 10 and 11 disclose a hinged crescent-shaped refillable tray 40 c having a first portion 46 and a second portion 50 . Both the first portion 46 and the second portion 50 have a hinge end 48 coupled to a hinge 44 . Both the first portion 46 and the second portion 50 also have a grip end 42 which, when squeezed together, cause the refillable tray 40 c to contract. While contracted, the refillable tray 40 c may be inserted into the sink drain 12 . Upon spreading apart or releasing the grip ends 42 , the refillable tray 40 c will expand and be held in place within the sink drain 12 .
[0048] Although it is preferred that the hinge 24 of the deodorizing ring 20 c and the hinge 44 of the refillable tray 40 c be one of a living hinge and a locking hinge, it should be clearly understood that substantial benefit may be derived from the use of a spring hinge.
[0049] Referring now to FIGS. 13-16 , the device for deodorizing a sink drain 10 may also be dimensioned to be coupled proximate an exterior portion 16 of the sink drain 12 . FIGS. 13 and 14 show a deodorizing ring 20 d having a plurality of legs 32 . Each leg 32 has a first end 34 coupled to a portion of the deodorizing ring 20 d and each leg 32 also has a second end 36 extending substantially downwardly from the deodorizing ring 20 d . Each second end 36 is also dimensioned to couple the deodorizing ring 20 d to the sink drain 12 so as to support the deodorizing ring 20 d above the sink drain 12 .
[0050] Similarly, FIGS. 15 and 16 show a refillable tray 40 d having a plurality of legs 52 . Each leg 52 has a first end 54 coupled to a portion of the refillable tray 40 d and each leg 52 also has a second end 56 extending substantially downwardly from the refillable tray 40 d . Each second end 56 is also dimensioned to couple the refillable tray 40 d to the sink drain 12 so as to support the refillable tray 40 d above the sink drain 12 .
[0051] Although, in the embodiments of the device for deodorizing a sink drain 10 shown in FIGS. 13-16 , it is preferred that deodorizing ring 20 d have a plurality of legs 32 or that the refillable tray 40 d have a plurality of legs 52 , it should be clearly understood that substantial benefit may be derived from alternate configurations of the deodorizing ring 20 d or the refillable tray 40 d , so long as the deodorizing ring 20 d or the refillable tray 40 d is supported above the sink drain 12 .
[0052] In order to combat odors, it is preferred that the device for deodorizing a sink drain 10 contain a deodorizing agent, such as a surfactant or caustic soda. In order to remove drain clogs, it is preferred that the device for deodorizing a sink drain 10 contain a clog removing agent, such as an enzyme or bleach.
[0053] It should be clearly understood that substantial benefit could be derived from: 1) a device for deodorizing a sink drain 10 directed to deodorizing drains in which each deodorizing ring 20 contains only a deodorizing agent; 2) a device for deodorizing a sink drain 10 directed to treating drain clogs in which each deodorizing ring 20 contains only a clog removing agent; or 3) a device for deodorizing a sink drain 10 directed to both deodorizing and treating clogs in which some deodorizing rings 20 contain a deodorizing agent while others contain a clog treating agent or in which each deodorizing ring 20 contains both a deodorizing agent and a clog treating agent.
[0054] It is also preferred that the device for deodorizing a sink drain 10 contain a fragrance.
[0055] As shown in FIGS. 17 and 18 , it is further preferable that the device for deodorizing a sink drain 10 have a wear indicator 60 integrally coupled to at least one of the deodorizing ring 20 (see FIG. 17 ) and the refillable tray 40 (see FIG. 18 ). Preferably, the wear indicator 60 is integral to the deodorizing ring 20 . The wear indicator 60 is adapted to signal a user to replace the device for deodorizing a sink drain 10 after an amount of wear on the device for deodorizing a sink drain 10 . Presumably, the flow of water through the sink drain 10 will activate the wear indicator 60 , although it should be understood that substantial benefit could be derived from a wear indicator 60 that utilizes alternative means for identifying the amount of wear.
[0056] As shown in FIG. 17 , the wear indicator 60 may be a color that fades as the at least one deodorizing ring 20 is diminished by use. Alternatively, the wear indicator 60 may be a color that gradually changes to another color as the at least one deodorizing ring 20 is diminished by use. Instead of a color indicator, each deodorizing ring 20 may also be comprised of a material adapted to dissolve after an amount of wear of the deodorizing ring 20 . While, in the preferred embodiment, the device for deodorizing a sink drain 10 comprises a wear indicator 60 , it should be clearly understood that substantial benefit could be derived from an alternative configuration of the device for deodorizing a sink drain 10 in which there is no wear indicator 60 .
STATEMENT OF OPERATION
[0057] In order to operate the device for deodorizing a sink drain 10 , one places it either directly into the sink drain 12 such that it is directly abutting an interior wall of the sink drain 12 , or places it proximate an exterior portion of the sink drain 12 . After an amount of use of the device for deodorizing a sink drain 10 , the user removes the deodorizing ring 20 or removes the refillable tray 40 in order to replace the deodorizing ring 20 .
[0058] While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention. For example, although the device for deodorizing a sink drain is shown to be retained by frictional engagement with the interior wall of the drain (see FIGS. 1-12 ), substantial benefit may be obtained from the device merely resting upon the bottom portion of the sink drain or upon the rubber splash guards found over the garbage disposal. It should also be understood that substantial benefit may be derived from the device being retained above, as well as below, the rubber splash guards. It should be further understood that although the device is shown as being used with a sink drain having a garbage disposal unit, substantial benefit may be obtained from using the device with a sink drain that is not equipped with a garbage disposal unit.
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A device for deodorizing a sink drain that allows the sink drain to remain substantially entirely open. Preferably, the device would deodorize sink drains. Further preferably, the device would treat sink drain clogs. Further preferably, the device would both deodorize the sink drain and treat sink drain clogs. Still further preferably, the device would have a wear indicator to signal the user when a new device is needed.
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This application is a continuation of application Ser. No. 07/464,582 filed on Jan. 11, 1990, now abandoned, which is a continuation of Ser. No. 07/325,011 filed on Mar. 17, 1989, now abandoned, which is a continuation of Ser. No. 07/111,259 filed on Oct. 22, 1987, now abandoned.
FIELD OF THE INVENTION
The present invention relates to the preparation of 4,4'-diaminodiphenylmethane and derivatives thereof, the preparation being effected by the reaction, in the presence of a zeolite catalyst, of aniline or a derivative thereof with formaldehyde, or by the isomerization of N-(4-aminobenzyl)aniline or a derivative thereof.
DESCRIPTION OF THE PRIOR ART
As is well-known 4,4'-diaminodiphenylmethane is used as an inhibitor of corrosion, or as an intermediate substance for obtaining the corresponding diisocyanate, which is a very important product in the chemical industry, used for the synthesis of polymers, polyurethanes, epoxy resins and the like.
It is normally obtained from aniline or an aniline derivative. The recognized traditional process used for the production of 4,4'-diaminodiphenylmethane (J.Am. Chem. Soc. 57,888, 1975; Chem Tech, Nov. 1984, p.670; Kirk Othmer, Vol II, 3rd Edition, pp. 338-348) consists of causing aniline to react with formaldehyde in a concentrated strong acid solution (e.g. HCl, H 2 SO 4 , H 3 PO 4 , etc.).
Alternatively, a amine derivative can be used, such as methyl phenylcarbonate, which is condensed with formaldehyde to produce diurethane. From this, by pyrolysis, a diisocyanate can be obtained, with the free amine phase being by-passed. The general formula for the aniline derivatives that can be used is: ##STR1## wherein R=--COOR' or --COR wherein R' is alkyl or aryl, either substituted or unsubstituted. Let us take as an example the case where R is --COOMe:
The conditions that are normally used in the known process require an excess of aniline, or one of its derivatives, relative to the formaldehyde, and a large quantity of strong soluble acid. Both of these conditions are indispensable requirements to ensure that the formation of-undesirable by-products is kept in check.
Under known procedure, therefore, the industrial production process suffers from the need to use large quantities of strong acid, which in turn necessitates the use of corrosion-resistant materials in the construction of the production plant. Apart from this, after the reaction has taken place, large amounts of bases are required to neutralize the acids, and this causes problems as regards the disposal of the resulting inorganic salts. A further problem arises when hydrochloric acid is used, since this leads to the formation of dichloromethane ether by the formaldehyde, which is a highly toxic substance.
SUMMARY OF THE INVENTION
It has now surprisingly been discovered, and this constitutes one of the subjects of the present invention, that the reaction in the form of a condensation with formaldehyde, or with a product capable of producing formaldehyde, under reactive conditions can be effected with the use of zeolite substances.
The resulting advantages are that a corrosion-free plant can be used; that a recyclable reagent (i.e. the zeolite) can be used; that expenditure on acids and bases is no longer necessary; and that the problem of the need to dispose of inorganic by-products does not arise. Zeolite, moreover, because of its particular porous crystalline solid structure and controlled 10 porosity, favours the formation of the 4,4'-diaminodiphenylmethane isomer (or derivatives thereof) at the expense of the other isomers and higher oligomers.
As a reagent, any substance that is capable of giving rise to formaldehyde under reactive conditions can be used. In particular, gaseous formaldehyde, or formaldehyde dissolved in solvent or trioxane, can be used.
The reaction can be carried out in an inert solvent, such as an alcohol, an aromatic or aliphatic hydrocarbon, an ether, or a chloroaromatic or nitroaromatic compound, etc., preferably at a temperature of the order of 50° C. to 200° C., generally from 100° C. to 150° C., and preferably by a solvent reflux process or in an autoclave, depending on the boiling point of the solvent used.
The pressure in the system is usually autogenous. It is preferable to use an excess of aniline relative to the formaldehyde, although the ratio between them is not as critical as it is when a mineral acid is used for condensation purposes. This is because the porosity of the zeolite impedes the formation of higher oligomers. This means that it is possible to operate with higher conversions, thus making savings in regard to acrolein recycling.
Reduced yields sometimes occur with the synthesis of 4,4'-diaminodiphenylmethane owing to the formation of appreciable quantities of N-(aminobenzyl)aniline and derivatives. As is known, these products can be isomerized in terms of diamino-derivatives through a catalyzed acid reaction: ##STR2##
This reaction generally occurs in the presence of an excess of amine, through the action of a strong acid or carboxylic acid.
Often the acids concerned (e.g. trifluoroacetic acid and trifluoromethane-sulphonic acid) are expensive and used in massive quantities and need to be neutralized with soda once the reaction has taken place.
Moreover, unless appropriate construction materials are used, these substances can also cause corrosion in the production plant.
It has surprisingly been discovered that, and this constitutes another subject of the present invention, that isomerization can be effectively carried out with the use of catalysts of zeolite type. This isomerization reaction, which when the above-described synthesis is performed can be a direct result of the use of the zeolitic catalyst, can of course be used whatever basic method is employed for the preparation of 4,4'-diaminodiphenylmethane. The process, whether it is the reaction of aniline in the presence of zeolites (in this case the process can be accompanied by the analysis of the products), or whether N-(aminobenzyl) aniline, obtained by various means, is used, can be carried out in an inert solvent, e.g. a saturated or aromatic hydrocarbon, an ether, an alcohol, or a chloroaromatic or nitroaromatic compound, at a temperature of from ambient temperature to 200° C., generally from 70° C. to 150° C. The reaction pressure is usually autogenous.
DETAILED DESCRIPTION
The preferred types of zeolite that are used in the processes that are the subject of the present invention are those corresponding to the following general formula, expressed in terms of molar ratios of oxides (in calcined anhydrous form):
(1) pHAlO 2 qB 2 O 3 ·SiO 2
In formula (1), p has a value of from 0.034 to 0.0050 and q of a value of from 0.1 to 0.005, with the H + of the HAlO 2 being replaceable, at least in part, by cations. This zeolite has an X-ray diffraction spectrum (powder sampling) whose significant lines are as given in Table A:
TABLE A______________________________________ d I.sub.rel______________________________________ 11.12 + 0.10 vs 9.98 + 0.10 s 9.74 + 0.10 m 6.34 + 0.07 mw 5.97 + 0.07 mw 4.24 + 0.05 mw 3.84 + 0.04 s 3.81 + 0.04 s 3.73 + 0.04 s 3.71 + 0.04 s 3.63 + 0.04 m 3.04 + 0.02 mw 2.97 + 0.02 mw______________________________________
wherein d are the interplanar distances in Angstroms and I rel the relative strengths, with vs standing for very strong, s for strong, m for medium, mw for medium weak and w for weak, and an IR spectrum having the following bands:
______________________________________ wn I.sub.rel______________________________________ 1220-1230 w 1080-1110 s 890-920 mw 795-805 mw 550-560 m 450-470 ms______________________________________
wherein wn stands for the wave number in cm -1 and I rel for the relative strengths, with s standing-or strong, ms for medium strong, m for medium, mw for medium weak and w for weak.
(2) pHAlO 2 ·qTiO 2 ·SiO 2
In the formula (2), p has a value greater than zero and less than or equal to 0.050 and q has a value greater than zero and less than or equal to 0.025, with the H + of the HAlO 2 being replaceable, in part at least, by cations. This zeolite has an X-ray diffraction spectrum (powder sampling) whose more significant lines are as given in Table B:
TABLE B______________________________________ d I.sub.rel______________________________________ 11.14 + 0.10 vs 9.99 + 0.10 s 9.74 + 0.10 m 6.36 + 0.07 mw 5.99 + 0.07 mw 4.26 + 0.05 mw 3.86 + 0.04 s 3.82 + 0.04 s 3.75 + 0.04 s 3.72 + 0.04 s 3.65 + 0.04 m 3.05 + 0.02 mw 2.99 + 0.02 mw______________________________________
wherein d are the interplanar distances in Angstroms and I rel the relative strengths, with vs standing for very strong, s for strong, m for medium, mw for medium weak and w for weak, and an IR spectrum having at least the following bands:
______________________________________ wn I.sub.rel______________________________________ 1220-1230 w 1080-1110 s 960-975 mw 795-805 mw 550-560 m 450-470 ms______________________________________
wherein wn stands for the wave number in cm -1 and I rel for the relative strengths, with s standing for strong, ms for medium strong, m for medium, mw for medium weak and w for weak.
(3) ZSM-5 (as per U.S. Pat. No. 3,702,886 and U.S. Reissue Pat. No. 29948)
4) xTiO 2 ·(1-x)SiO 2
In formula (4), x is from 0.0001 to 0.04, usually from 0.01 to 0.025 (for further particulars see U.S. Pat. No. 4,410,501).
(5) pHFeO 2 ·qTiO 2 ·SiO 2
In formula (5), p has a value greater than zero but less than or equal to 0.050 and q has a value greater than zero but less than or equal to 0.025, with the H + of the HFeO 2 being replaceable or replaced, at least in part, by cations. This zeolite has an X-ray diffraction spectrum (powder sampling) whose more significant lines are as given in Table C:
TABLE C______________________________________ d I.sub.rel______________________________________ 11.14 + 0.10 vs 9.99 + 0.10 s 9.74 + 0.10 m 6.36 + 0.07 mw 5.99 + 0.07 mw 4.26 + 0.05 mw 3.86 + 0.04 s 3.82 + 0.04 s 3.75 + 0.04 s 3.72 + 0.04 s 3.65 + 0.04 m 3.05 + 0.02 mw 2.99 + 0.02 mw______________________________________
wherein d are the interplanar distances in Angstroms and I rel the relative strengths, with vs standing for very strong, s for strong, m for medium, mw for medium weak and w for weak, and an IR spectrum having at least the following bands:
______________________________________ wn I.sub.rel______________________________________ 1220-1230 w 1080-1110 s 960-975 mw 795-805 mw 550-560 m 450-470 ms______________________________________
wherein wn stands for the wave number in cm -1 and I rel for the relative strengths, with s standing strong, ms for medium strong, m for medium, mw for medium weak and w for weak.
(6) Y zeolites partly in acid form and exchanged by metal cations, including SK 40, SK 41 and SK 500, as marketed by Union Carbide's Linde Division.
Zeolites nos. 1,2,3,4,5 and 6, respectively, can be prepared by the processes described below.
ZEOLITE NO. 1
A derivative of silicon, a derivative of boron, a derivative of aluminium and a nitrogenous organic base are caused to react under hydrothermal conditions, the SiO 2 /Al 2 O 3 molar ratio of the reagents being greater than 100 and generally from 300 to 400, the SiO 2 /B 2 O 3 molar ratio of the reagents being from 5 to 50 and the H 2 O/SiO 3 ration of the reagents being generally from 20 to 40, with as appropriate the presence of a salt or salts and/or alkali metal hydroxides or alkaline earth metal hydroxides with an M/SiO 2 molar ratio (where M is the alkali metal cation and/or the alkaline earth metal cation) for the reagents of less than 0.1 and usually less than 0.01 or zero.
In the empirical formula for the material, aluminium has been shown as HAlO 2 , to indicate that the material in question is in H + form; in referring to the ratios between the various reagents, however, we use the symbol Al 2 O 3 , since this is more commonly used.
The derivatives of silicon is generally selected from silica gel, silica sol and alkyl silicates, generally tetraethyl silicate; the derivative of boron is generally selected from boric acid and the organic derivatives of boron, for instance the alkyl borates, with triethyl borate being the one generally used; the derivative of aluminium is generally selected from the salts thereof, such as, for example, the halides and hydroxides, and the organic derivatives thereof, such as the alkyl aluminates, usually isopropylaluminate.
The nitrogenous organic base can be an alkylammonium hydroxide; tetrapropylammonium hydroxide is the usual base.
If tetrapropylammonium hydroxide is used, the TPA + /SiO 2 ratio (where TPA=tetrapropylammonium) of the reagents is usually between 0.1 and 1, and more usually between 0.2 and 0.4.
The reagents are usually caused to react at an operating temperature of from 100 to 200° C., and generally from 160 to 180° C., at a pH of from 9 to 14, mostly from 10 to 12, and for a period of time varying from 1 hour to 5 days, but generally from 3 to 10 hours.
ZEOLITE NO 2
A derivative of silicon, a derivative of titanium, a derivative of aluminium and a nitrogenous organic base are caused to react under hydrothermal conditions, with the SiO 2 /Al 2 O 3 , molar ratio of the reagents being greater than 100 and usually from 300 to 400, with the SiO 2 /TiO 2 molar ratio being greater than 5, generally from 15 to 25, and with the H 2 O/SiO 2 ratio being, in general, from 10 to 100, more usually from 30 to 50, with, as appropriate, the presence of a salt or salts and/or an alkali metal hydroxide or an alkaline earth metal hydroxide, with a M/SiO 2 (where M is the alkali metal cation and/or alkaline earth metal cation) molar ratio of the reagents of less than 0.1, generally less than 0.01, or zero.
In the empirical formula for the material, aluminium has been represented by HAlO 2 , to indicate that the material is in H + form; in referring to the ratios between the various reagents, however, we use the symbol Al 2 O 3 , since this is more commonly used.
The derivative of silicon is generally selected from silica gel, silica sol and the alkyl silicates, of which tetraethyl silicate is generally used; the derivative of titanium is generally selected from salts thereof, the halides for example, and organic derivatives thereof, such as, for instance, alkyl titanates, of which tetraethyl titanate is mostly used; the derivative of aluminium is usually selected from salts thereof, such as the halides and hydroxides, for example, and from organic derivatives thereof, such as alkyl aluminates, usually isopropylaluminate.
The nitrogenous organic base can be alkylammonium hydroxide, usually tetrapropylammonium hydroxide.
If tetrapropylammonium hydroxide is used, the TPA + /SiO 2 ratio (where TPA=tetrapropylammonium) of the reagents is usually from 0.1 to 1, mostly from 0.2 to 0.4.
The reagents are usually caused to react at an operating temperature of from 100 to 200° C., more usually from 160 to 180° C., at a pH of from 9 to 14, mostly from 10 to 12, and for a period of time of from 1 hour to 5 days, generally from 3 to 10 hours.
ZEOLITE NO. 3
ZMS-5 is prepared as per U.S. Pat. No. 3,702,886 or U.S. Reissue Pat. No. 29948.
ZEOLITE NO. 4
This is prepared as per U.S. Pat. No. 4,410,501.
ZEOLITE NO. 5
A derivative of silicon, a derivative of titanium, a derivative of iron and a nitrogenous organic base are caused to react under hydrothermal conditions, with a SiO 2 /Fe 2 O 3 molar ratio of the reagents greater than 50 and usually from 150 to 600, a SiO 2 /TiO 2 molar ratio of the reagents greater than 5, usually from 15 to 25, and a H 2 O/SiO 2 ratio of the reagents generally from 10 to 100, more preferably from 30 to 50, with as appropriate the presence of a salt or salts and/or an alkali metal hydroxide or alkaline earth metal hydroxide, with an M/SiO 2 molar ratio (where M is the alkali metal cation or alkaline earth metal cation) of the reagents of less than 0.1, usually less than 0.01, or zero.
In the empirical formula from the material, iron has been represented as HAlO 2 , to indicate that the material is in H + form; in referring to the ratios between the various reagents, however, we use the symbol Fe 2 O 3 , since this is more commonly used.
The derivative of silicon is usually selected from silica gel, silica sol and alkyl silicates, of which tetraethyl silicate is mostly used; the derivative of titanium is usually selected from salts thereof, the halides for example, and organic derivatives thereof, such as, for instance, alkyl titanates, of which tetraethyl titanate is generally used; the derivative of iron is usually selected from salts thereof, such as halides, for example, or from nitrates, hydroxides and organic derivatives such as, for instance, hydroxides thereof
The nitrogenous organic base can be alkylammonium hydroxide, tetrapropylammonium hydroxide being the most usual.
If tetrapropylammonium hydroxide is used, the TPA + /SiO 2 ratio (where TPA=tetrapropylammonium) of the reagents is usually from 0.1 to 1, more usually from 0.2 to 0.4.
The reagents are usually caused to react at an operating temperature of from 100 to 200° C., more usually from 160° C. to 180° C., at a pH or from 9 to 14, generally from 10 to 12, and for a period of time of from 1 hour to 5 days, usually from 3 to 10 hours.
ZEOLITE NO. 6
The preparation of Y zeolite involves the exchange, in part in acid form and subsequently with metal cations, of a commercial Y zeolite, including the types SK 40, SK 41 and SK 500 marketed by Union Carbide's Linde Division.
In another method of putting the present invention into effect, zeolites nos. 1,2,4 and 5 can be in a form wherein an amorphous oligomeric silica acts as a binder, whereby the molar ratio between the oligomeric silica and the zeolite no. 1 or zeolite no. 2 or zeolite no. 4 or zeolite no 5 is from 0.5 to 0.12, the crystals of zeolite no. 1 or zeolite no. 2 or zeolite no. 4 or zeolite no. 5 being caged by Si-O-Si bridges and the crystalline mass of zeolites and silica being in the form of microspheres with a diameter of from 5 to 1000 microns.
One process for preparing catalysts nos. 1,2,4 and 5 having the binder consists in dissolving zeolite no. 1 or zeolite no. 2 or zeolite no. 4 or zeolite no. 5 in an aqueous solution of silica and tetraalkylammonium hydroxide, generally with alkyls having from 1 to 5 carbon atoms and usually tetrapropylammonium, the solution being prepared by the hydrolization at a temperature of from ambient temperature to 200° C., usually from 40 to 100° C., of a tetraalkylorthosilicate, usually tetraethylorthosilicate, in a liquid state in an aqueous solution of tetraalkylammonium hydroxide, for a time of from 0.2 to 10 hours, each zeolite containing a percentage weight of organic base of from 7 to 12% and of water of from 23 to 28%, after which the suspension thus obtained is placed in a rapid drier.
The following examples are examples of specific methods of preparation of the zeolites used (not an exhaustive list).
EXAMPLE
ZEOLITE NO. 1
67.8 g of Al(NO 3 ) 3 ·9H 2 O were dissolved in 1275 g of ethyl alcohol, to which were added 2819 g of tetraethylsilicate, under constant agitation. The agitation was continued until a clear, homogeneous solution was obtained.
Next were added, in the order given, in a stainless steel receptacle, under agitation, 1036 g of de-ionized water, 8878 g of an aqueous solution of 15% by weight of tetrapropylammonium (TPA + ) hydroxide and 167.5 g of boric acid in powder form.
When the acid had dissolved, the solution previously obtained was added to it and the mixture was agitated and heated at 60° C. for approximately 4 hours, or at any rate until the silicate had been completely hydrolyzed and the ethyl alcohol present in the mixture had been virtually eliminated. The molar composition of the reaction mixture was as follows:
SiO 2 /Al 2 O 3 =150; SiO 2 /B 2 O 3 =10; TPA + /SiO 2 =0.5 H 2 O/SiO 2 =35.
The solution thus obtained was discharged into an autoclave equipped with an agitator and heated under agitation and autogenous pressure at 170° C. for 4 hours. After being discharged from the autoclave, the product was centrifuged and the residual cake thoroughly dispersed in 70 litres of de-ionized water. The suspension thus obtained was centrifuged once again to provide a washed cake.
The cake was calcined in air for 5 hours at 550° C., at the end of which time it was found to be a zeolite, the anhydrous form of which had the following composition:
0.0098 Al 2 O 3 ;0.0108 B 2 O 3 ; 1 SiO 2 .
EXAMPLE 2
ZEOLITE NO. 1 WITH BINDER
The procedure was the same as Example 1. Then, 219 g of tetraethylsilicate were added under vigorous agitation to 234 g of a solution of 12% by weight of tetrapropylammonium hydroxide. The mixture was agitated for 1 hour, then 958 g of demineralized water were added, followed by further agitation for another hour. This produced a clear solution in which the zeolite no. 1 previously prepared was thoroughly dispersed, containing 9% by weight of TPA + and 26% by weight of water.
The milky suspension resulting from the dispersion was fed into a spray-drier (namely a disc atomizer made by NIRO ATOMIZER, the air temperature at the entrance being 300° C. and 120° C. at the exit, and the diameter of the chamber being 1 5 m), which produced compact microspheres having an approximate average diameter of 20 microns.
The atomized product was placed in a muffle furnace in an atmosphere of N 2 and heated to 550° C. After remaining for two hours at this temperature in N 2 , the atmosphere was gradually lowered from N 2 to air pressure and the product left for a further two hours in air at 550° C. The product thus obtained had the following molar composition:
0.0088 Al 2 O 3 ;0.0097 B 2 O 3 ; 1SiO 2 .
EXAMPLE 3
27 g of isopropylate were dissolved in 5400 g of a solution of 18.7% tetrapropylammonium hydroxide by weight.
230 g of tetraethylorthotitanate were separately dissolved in 4160 g of tetraethylsilicate, and the solution was then added to the first solution, under agitation.
Next, the mixture was heated, still under agitation, at 50 to 60° C. until a single phase solution was obtained, whereupon 10 liters of water were added.
The solution thus obtained was placed in an autoclave and heated for four hours at 170° C. under autogenous pressure.
The product was then discharged, centrifuged and washed twice by redispersion and centrifuging. The washed cake was calcined in air for 5 hours at 550° C., at the end of which time it was found to be zeolite, the anhydrous form of which had the following composition:
0.0081 Al 2 O 3 ;0.0250 TiO 2 ; 1 SiO 2 .
EXAMPLE 4
ZEOLITE NO. 2 WITH BINDER
The procedure was the same as Example 3. Then, 320 g of tetraethylsilicate were added under vigorous agitation to 340 g of a solution of tetrapropylammonium hydroxide in a proportion of 12% by weight; the mixture was agitated for one hour, then 1400 g of demineralized water were added, followed by further agitation for another hour. This produces a clear solution in which the zeolite no. 2 previously prepared was thoroughly dispersed, containing 9% by weight of TPA + and 26% by weight of water.
The milky suspension resulting from the dispersion was fed into a spray-drier (namely a disc atomizer made by NIRO ATOMIZER, the air temperature at the entrance being 300° C. and 120° C. at the exit, and the diameter of the chamber being 1.5 m), which produced compact microspheres with an approximate average diameter of 20 microns.
The atomized product was placed in a muffle furnace in an atmosphere of N 2 and heated to 550° C. After remaining for two hours at the same temperature in N 2 , the atmosphere was gradually lowered from N 2 to air pressure, and the product left for a further two hours in air at 550° C. The product thus obtained had the following molar composition:
0.0073 Al 2 O 3 ;0.0225 TiO 2 ; 1SiO 2 .
EXAMPLE 5
ZEOLITE NO. 3
This is prepared as per U.S. Pat. No. 3,702,886 and U.S. Reissue Pat. No. 29948.
EXAMPLE 6
ZEOLITE NO. 4
This is prepared as per U.S. Pat. No. 4,410,501, and as follows.
Titanium silicate is first prepared as follows. 487 g of TiOCl 2 were dissolved in 26350 g of an aqueous solution of tetrapropylammonium hydroxide (TPA/OH) in the proportion of 14% by weight, and to this mixture were added, under vigorous agitation, 14538 g of colloidal silica in the proportion of 30%. The mixture was next heated at 60° C. for approximately two hours, being agitated throughout, after which 29680 g of mineralized water were added and the mixture was then agitated for a further hour at 60° C. The resulting clear solution, with the following molar composition:
5 TPA-PH;1TiO 2 ; 20 SiO 2 ; 800 H 2 O was placed in an autoclave, equipped with an agitator, under constant agitation at 170° for three hours.
The milky suspension thus obtained, containing zeolite microcrystals in suspension, was centrifuged and the residual cake is then washed by redispersion in water, following which it was recovered by means of further centrifuging.
At the same time 1346 g of tetraethyl silicate were added under vigorous agitation to 1437 g of a solution of tetrapropylammonium hydroxide in the proportion of 12% by weight and agitated for 1 hour. 5890 g of demineralized water were then added, and the mixture was agitated for a further hour. This produced a clear solution in which the titanium silicate previously prepared was thoroughly dispersed, containing 9% by weight of TPA + and 26% by weight of water.
The milky suspension resulting from this dispersion was fed into a spray-drier (namely a disc atomizer made by NIRO ATOMIZER, the air temperature at the entrance being 300° C. and 120° C. at exit, and the diameter of the chamber being 1.5 m), which produced compact microspheres with an appropriate average diameter of 20 microns.
The atomized product was placed in a muffle furnace in an atmosphere of N 2 and heated to 550° C. After remaining in N 2 at this temperature for two hours, the atmosphere was gradually lowered to air pressure, and the product left for a further two hours in air at 550° C. The product thus obtained has the following molar composition:
1 TiO 2 ;43 SiO 2 .
EXAMPLE 7
ZEOLITE NO. 5
This example describes how titanium silicalite is prepared.
202 g of Fe(NO 3 ) 3 ·9H 2 O were dissolved in water, and a precipitate of hydroxide was formed in the solution by the addition of ammonium hydroxide. The precipitate was filtered and washed by redispersion in cold water and filtering until the filtrate was neutralized. The subsequent step is for the wet hydroxide to be dissolved in 27000 g of a solution of tetrapropylammonium hydroxide in the proportion of 18.7% by weight. 1140 g of tetraethylorthotitanate were separately dissolved in 20800 g of tetraethylorthosilicate, and this solution was then added to the first solution under agitation.
The mixture was then heated at 50°-60° C., still under agitation, until a single phase solution was obtained, whereupon 50 litres of water were added.
The solution thus obtained was then fed into an autoclave and heated for four hours under autogenous pressure at 170° C.
After discharge the product was centrifuged and washed twice by means of redispersion and centrifuging, dried for 1 hour at 120° C. and then calcined for 4 hours at 550° C. in air.
The product thus obtained had the following composition:
0.0025 Fe 2 O 3 ;0.0208 TiO 2 ; 1 SiO 2 .
EXAMPLE 8
ZEOLITE 5 WITH BINDER
The process of Example 7 was followed, after which 1620 g of tetraethylsilicate were added under vigorous agitation to 1730 g of a solution of tetrapropylammonium hydroxide, 12% by weight, and the mixture was then agitated for 1 hour. Next, 7090 g of demineralized water were added and the whole was agitated for a further hour. This produced a clear solution in which the titanium silicalite previously prepared was thoroughly dispersed, containing 9% by weight of TPA + and 26% by weight of water.
The milky suspension resulting from the dispersion was fed into a spray-drier (namely a disc atomizer made by NIRO ATOMIZER, the air temperature at the entrance being 300° C. and 120° C. at the exit, and the diameter of the chamber being 1.5 m) which produced compact microspheres with an approximate average diameter of 20 microns.
The atomized product was placed in a muffle furnace in an atmosphere of N 2 and heated to 550° C. After remaining for 2 hours at this temperature in N 2 , the atmosphere was then gradually lowered to air pressure, and the product left for a further two hours in air at 550° C.
The product thus obtained had the following molar composition:
0.0023 Fe 2 O 3 ;0.0188 TiO 2 ; 1 SiO 2 .
EXAMPLES 9-14
12 ml of aniline, 1.5 g of trioxane dissolved in 60 ml of benzene and 3 g of catalyst were placed in a glass autoclave. The suspension was heated at 120° C. under agitation for a period of five hours. After it had cooled, the solvent was distilled off and the residue extracted using ethyl alcohol.
The reaction products were quantitatively analyzed and identified by gas chromatography and mass spectrometry in relation to authentic samples.
The results are shown in Table 1 below (the higher oligomers are not included).
EXAMPLES 15-18
12 ml of aniline, 1.5 g of trioxane dissolved in 60 ml of benzene and 3.3 g of catalyst with binder were placed in a glass autoclave. The suspension was heated under agitation at 120° C. for a period of five hours. After it had cooled, the solvent was removed and the organic part extracted using ethyl alcohol.
The reaction products were quantitatively analyzed and identified by gas chromatography and mass spectrometry in relation to authentic samples.
The results are shown in Table 2 below (the higher oligomers are not included).
EXAMPLE 19
12 ml of aniline, 6 g of trioxane dissolved in 60 ml of benzene and 3g of zeolite no. 1 were placed in a glass autoclave.
The suspension was heated under agitation at 120° C. for 5 hours. After being separated out from the zeolite in the manner described under the previous Examples, the reaction products were analyzed and identified by gas chromatography and mass spectrometry.
______________________________________Aniline conversion 29%Selectively in: N-(4-aminobenzyl) aniline 30%2,4'diaminodiphenylmethane 9%4,4'diaminodiphenylmethane 61%______________________________________
Traces of higher oligomers were present.
EXAMPLE 20
50 g of Y zeolite in sodium form (Union Carbide SK 40) were exchanged with 25 g of NH 4 Cl in 100 cc of water for two hours to allow settling. The zeolite was filtered and washed several times with deionized water, then dried and calcined for 4 hours at 550° C.
2 g of the zeolite prepared in this way were then suspended in a solution of 8 g of aniline and 1 g trioxane in 40 cc of benzene, in a glass autoclave.
The suspension was heated under agitation for 4 hours at 120° C. After the solvent had been cooled and distilled off, the organic part was extracted by means of ethyl alcohol. The reaction products were analyzed quantitatively by gas chromatography and mass spectrometry.
______________________________________Aniline conversion 6%Selectively in: N-(4-aminobenzyl)aniline 10%2,4'-diaminodiphenylmethane 29%4,4'-diamiodiphenylmethane 59%Higher oligomers 2%______________________________________
EXAMPLES 21-29
8 g of Y zeolite in exchanged H + form (see Example 20) were suspended in 50 ml of water containing 3.8×10 -3 moles of preselected salt. The suspension was heated for settling for 2 hours and then filtered. The solid was washed several times with distilled water and then dried at 110° C.
Zeolites exchanged in this manner have the composition given in Table 3 below.
2 g of a zeolite prepared in this way were suspended in a solution of 8 g of aniline and 1 g of trioxane in 40 cc of benzene in a glass autoclave. The mixture was heated at 120° C. under agitation for 1 hour and, after the solvent had been cooled and distilled off, the reaction products were extracted from the residue by using ethyl alcohol, and subsequently quantified by gas chromatography and mass spectrometry. The results are given in Table 4 below.
EXAMPLE 30
12 g of acetanilide, 1.5 g of trioxane and 60 cc of benzene, with 4 g of zeolite no.1, were placed in a glass autoclave for 6 hours at 120° C., and agitated magnetically. The solvent was removed from the reaction mixture by extraction with alcohol, and the product submitted to quantitative analysis by means of gas chromatography and mass spectrometry. The sole derivative of the acetanilide was 4,4'-diacetylaminodiphenylmethane (26% yield).
EXAMPLE 31
A solution of 10 g of methyl N-phenylcarbamate and 2 g of trioxane were placed in an autoclave along with 3 g of zeolite no.2. The suspension was heated under agitation for two hours at 150° C. after which it was cooled and the solvent evaporated. The organic part was extracted from the residue by alcohol and analyzed by gas chromatography and mass spectrometry for comparison with authentic samples. The results were:
______________________________________Methyl phenylcarbamate 6.1 g4,4'-bis(methoxycarbonylamino) 3.0 gdiphenylmethane2,4'-bis(methoxycarbonylamino) 0.3 gdiphenylmethaneN-(methoxycarbonyl-N-(4-methoxycarbonylamine) 0.5 g.aniline______________________________________
EXAMPLE 32
A solution of 8 g of methyl N-phenylcarbamate and 1.5 g of trioxane were placed in an autoclave together with 2 g of zeolite Y partly in H + form and exchanged with FeCl 3 (see Example No. 2 and Table 3). The suspension was heated under agitation for 3 hours at 120° C., after which it was cooled and the solvent evaporated. The organic part was extracted with alcohol and submitted to analysis by gas chromatography and mass spectrometry for comparison with authentic samples. The results were:
______________________________________Methyl N-phenylcarbamate 4.1 g4,4'-bis(methoxycarbonylamino) 3.1 gdiphenylmethane2,4'-bis(methoxycarbonylamino) 0.3 gdiphenylmethaneN-(methoxycarbonyl-N-(4-methoxycarbonylamino) 0.4 g.aniline______________________________________
EXAMPLE 33
2 g of N-(4-aminobenzyl)aniline were placed in a glass autoclave together with 20 cc of benzene, 2 g of aniline and 1 g of zeolite no.1. The mixture was heated at a temperature of 135° C. for 3 hours, and agitated magnetically. The solvent was evaporated after being cooled, and the organic part extracted from the residue by alcohol. The reaction products were then analyzed and quantified by gas chromatography and mass spectrometry. The results were:
______________________________________Aniline 1.9 gN-(aminobenzyl)aniline 0.2 g2,4'-diaminodiphenylmethane 0.1 g4,4'-diaminodiphenylmethane 1.6 g.______________________________________
The ethanol was distilled off from the solution and the oily residue redissolved in benzene. The solvent was then re-evaporated, 20 cc of benzene being used for the recovery, and the solution was placed in a glass autoclave together with 1 g of zeolite no.2. It was next heated at 120° C. for 3.5 hours, and agitated throughout. From analysis, the new distribution of the products of the reaction process (without aniline) was found to be as follows:
______________________________________N-(4-aminobenzyl)aniline 8%2,4'-diaminodiphenylmethane 15%4,4'-diaminodiphenylmethane 77%.______________________________________
EXAMPLE 35
2 g of N-(aminobenzyl)aniline were placed in a glass autoclave together with 20 cc of benzene, 2 g of aniline and 1.1 g of zeolite no.1 with binder. The mixture was then heated at a temperature of 135° C. for 3 hours, and agitated magnetically. After cooling, the mixture from the reaction process was analyzed, with the following results:
______________________________________Aniline 1.9 gN-(aminobenzyl)aniline 0.2 g2,4'-diaminodiphenylmethane 0.1 g4,4'-diaminodiphenylmethane 1.6 g.______________________________________
EXAMPLE 36
6 ml of aniline and 1 g of trioxane were dissolved in 30 cc of benzene and caused to react with 2.2. g of zeolite no.5 with binder in an autoclave, under agitation, at 120° C. for 5 hours. The solvent was evaporated from the reaction mixture, and the residue dissolved in ethanol and filtered for elimination of the catalyst. The products of the reaction were then analyzed and quantified by gas chromatography and mass spectrometry, with the following results:
______________________________________Aniline conversion 22%Selectivity in: N-(aminobenzyl)aniline 41%2,4'-diaminodiphenylmethane 15%4,4'-diaminodiphenylmethane 44%.______________________________________
The ethanol was distilled off from the solution and the oily residue redissolved in benzene. The solvent was re-evaporated and 20 cc of benzene were used for recovery. Next, the mixture was placed in a small glass autoclave-together with 1.1 g of zeolite no. 2 with binder. The whole was then heated for 3.5 hours at 120° C., under constant agitation.
When analyzed, the products of the reaction (leaving out aniline) were found to be as follows:
______________________________________N-(aminobenzyl)aniline 8%2,4'-diaminodiphenylmethane 15%4,4'-diaminodiphenylmethane 77%.______________________________________
EXAMPLE 37
2 g of N-(aminobenzyl)aniline were placed in a glass autoclave together with 20 cc of benzene, 2 g of aniline and 1 g of zeolite. The mixture was heated at a temperature of 145° C. for 4 hours, and was magnetically agitated throughout. After it had been cooled the mixture resulting from the reaction was analyzed. The results were:
______________________________________Aniline 1.9 gN-(aminobenzyl)aniline 0.4 g2,4'-diaminodiphenylmethane 0.1 g4,4'-diaminodiphenylmethane 1.4 g.______________________________________
EXAMPLE 40
2 g of N-(4-aminobenzyl)aniline were placed in a glass autoclave together with 20 cc of benzene, 2 g of aniline and 1.1 g of zeolite 5 with binder. The mixture was heated at a temperature of 145° C. for 4 hours, and was magnetically agitated throughout. After it had been cooled the mixture resulting from the reaction was analyzed. The results were:
______________________________________Aniline 1.9 gN-(aminobenzyl)aniline 0.4 g2,4'-diaminodiphenylmethane 0.1 g4,4'-diaminodiphenylmethane 1.4 g.______________________________________
EXAMPLE 39
3 g of N-(4-aminobenzyl)aniline were placed in a glass autoclave together with 30 cc of benzene, 1.5 g of aniline and 1 g of zeolite ZSM-5. The mixture was heated at a temperature of 135° C. for 3.5 hours, and was magnetically agitated throughout. After the mixture had been cooled, the solvent had been evaporated and the organic part extracted from the residue, the mixture resulting from the reaction was submitted to chromatographic and mass spectrometric analysis. The results were:
______________________________________Aniline 1.4 gN-(aminobenzyl)aniline 0.3 g2,4'-diaminodiphenylmethane 0.3 g4,4'-diaminodiphenylmethane 2.3 g.______________________________________
EXAMPLE 40
10 g of zeolite Y in sodium form (Union Carbide SK 40) were suspended in a solution of 5 g of ammonium chloride and 30 cc of water.
The suspension was heated for settling for 2.5 hours, then cooled, filtered and washed several times with distilled water. The solid, after being dried at 100° C., was calcined at 500° C. for 6 hours.
1 g of zeolite prepared in this manner was suspended in a solution of 2 g of N-(4-aminobenzyl)aniline and 1 g of aniline in 20 cc of toluene. The solution was then heated for 3 hours at a temperature of 130° C., and magnetically agitated throughout.
The reaction mixture, after cooling, was submitted to analysis and was found to have the following chemical composition:
______________________________________Aniline 1 gN-(aminobenzyl)aniline 0.4 g2,4'-diaminodiphenylmethane 0.25 g4,4'-diaminodiphenylmethane 1.35 g.______________________________________
EXAMPLES 41-49
8 g of zeolite Y in exchanged H + form (see Example 40) were suspended in 50 ml of water in which 3.8×10 -3 moles of preselected metallic salt had been dissolved. The suspension was heated for settling for 2 hours, and then filtered. The solid was washed several times with distilled water and then dried at 110° C. Zeolites treated in this manner were found to have the compositions given in Table 5 below.
1 g of zeolite prepared in this manner was suspended in a solution of 2 g of N-(4-aminobenzyl) aniline and 1 g of aniline in 20 cc of benzene.
The solution was then heated for 1.5 hours at a temperature of 120° C., and magnetically agitated throughout.
After cooling, the mixture resulting from the reaction was analyzed. The results are given in Table 6 below.
TABLE 1__________________________________________________________________________ PRODUCT SELECTIVITY (%)ZEOLITE ANILINE N-(4-AMINOBENZYL) 2,4' DIAMINO- 4,4' DIAMINO-CATALYST CONVERSION % ANILINE DIPHENYLMETHANE DIPHENYLMETHANE__________________________________________________________________________-- 0 -- -- --1 30 28 10 622 29 14 11 753 31 40 16 444 6 50 20 305 18 40 14 46__________________________________________________________________________
TABLE 2__________________________________________________________________________ PRODUCT SELECTIVITY (%)ZEOLITE ANILINE N-(AMINOBENZYL) 2,4' DIAMINO- 4,4' DIAMINO-CATALYST CONVERSION % ANILINE DIPHENYLMETHANE DIPHENYLMETHANE__________________________________________________________________________-- 0 -- -- --1 30 28 10 622 29 14 11 753 6 50 20 304 16 16 14 70__________________________________________________________________________
TABLE 3__________________________________________________________________________ SALT USED FOR % OF METAL WEIGHT LOSSNO. EXCHANGE SiO.sub.2 (%) Al.sub.2 O.sub.3 (%) Na.sup.+ (%) EXCHANGED AT 450° C.__________________________________________________________________________ (%)1 Fe(CH.sub.3 COO).sub.3.4H.sub.2 O 56.81 16.76 2.53 2.13 11.232 FeCl.sub.3.6H.sub.2 O 54.94 15.54 1.41 3.30 17.693 Cu(CH.sub.3 COO).sub.2.H.sub.2 O 55.68 15.75 2.95 2.17 13.684 CuCl.sub.2.2H.sub.2 O 53.85 15.86 1.66 1.03 21.675 LaCl.sub.3.nH.sub.2 O 51.51 16.34 1.84 3.76 22.866 CaCl.sub.2.6H.sub.2 O 52.81 15.45 1.70 0.16 24.817 NiCl.sub.2.6H.sub.2 O 57.31 16.48 2.30 1.99 15.288 CaCl.sub.2.6H.sub.2 O 52.28 15.31 1.64 0.977 25.769 Co(CH.sub.3 COO).sub.2.4H.sub.2 O 52.81 15.51 2.66 2.21 22.43__________________________________________________________________________
TABLE 4__________________________________________________________________________ Selectivity in TABLE 3 ANILINE N-(4-AMINO-EXAMPLE ZEOLITE CONVERSION BENZYL) 2,4'-DIAMINO- 4,4'-DIAMINO- HIGHERNO. no. % ANILINE % DIPHENYLMETH. % DIPHENYLMETH. OLIGOMERS__________________________________________________________________________ %21 1 10 10 15 74 122 2 16 7 11 80 223 3 12 9 18 72 124 4 15 7 13 79 125 5 20 8 11 80 126 6 11 12 14 72 227 7 14 9 12 78 128 8 15 10 13 75 229 9 10 10 14 75 1__________________________________________________________________________
TABLE 5__________________________________________________________________________ Salt used for SiO.sub.2 Al.sub.2 O.sub.3 Na.sup.+ Metal Loss of weightNO. exchange % % % exchanged (%) at 450° C. (%)__________________________________________________________________________41 Fe(CH.sub.3 COO).sub.3.4H.sub.2 O 56.81 16.76 2.64 2.13 11.2342 FeCl.sub.3.6H.sub.2 O 54.04 15.54 1.41 3.30 17.6943 Cu(CH.sub.3 COO).sub.2.H.sub.2 O 55.68 15.75 2.95 2.17 13.6844 CuCl.sub.2.2H.sub.2 O 53.85 15.86 1.66 1.03 21.6745 LaCl.sub.3.nH.sub.2 O 51.51 16.34 1.84 3.76 22.8646 LaCl.sub.2.H.sub.2 O 52.81 15.45 1.70 0.16 24.8147 NiCl.sub.2.6H.sub.2 O 57.31 16.48 2.30 1.99 15.2848 CoCl.sub.2.6H.sub.2 O 52.28 15.31 1.64 0.977 25.7649 Co(CH.sub.3 COO).sub.2.4H.sub.2 O 52.81 15.51 2.66 2.21 22.43__________________________________________________________________________
TABLE 6__________________________________________________________________________ Table 1 Zeo- Qty of aniline N-(4-aminobenzyl) 2,4'-diaminodiphenyl- 4,4'-diaminodiphenyl-Example No. lite No. recovered in g aniline in g methane in g methane in g__________________________________________________________________________50 1 1.0 0.40 0.25 1.3551 2 0.9 0.11 0.19 1.6852 3 1.0 0.30 0.31 1.3853 4 1.0 0.20 0.27 1.5254 5 0.9 0.12 0.23 1.6555 6 0.9 0.41 0.29 1.3056 7 0.9 0.22 0.31 1.4657 8 1 0.20 0.27 1.5258 9 1 0.30 0.26 1.44__________________________________________________________________________
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Process for the preparation of 4,4'-diaminodiphenylmethane and its derivatives.
4,4'-diaminodiphenylmethane and its derivatives are prepared by the condensation of aniline, or its derivative, and aldehyde, or its precursor and/or isomerization of appropriate intermediate products. The reaction proceeds with zeolites acting as catalysts; these catalysts, which are selected in accordance with the reaction to be effected, are preferably zeolites based on Si, Al and B; Si, Al and Ti; Ti and Fe; ZSM-5; or Y zeolites.
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BACKGROUND OF THE INVENTION
This invention describes new and useful methods for the degradation and removal of lignin from lignocellulosic materials; to delignify and brighten cellulosic pulps in bleaching; to produce cellulosic pulps for use in paper and paperboard manufacture and the manufacture of regenerated cellulose products; to enhance the strength, optical properties and other properties of recycled cellulosic fibers; to produce fodders having increased digestibility to ruminants; and to produce any other product in which the: degradation of or the removal of lignin from a lignocellulosic material produces beneficial results.
Lignocellulosic materials is a broad term that can be applied to a wide range of materials generally derived from plants or other organic sources. A primary example of such a material is wood. As is generally true for lignocellulosics, wood is composed of two main parts-a fibrous carbohydrate or cellulosic portion, and a non-fibrous portion comprising a complex chemical, commonly referred to as lignin. A major economic use of wood is derived from the conversion of the wood into a form suitable for the manufacture of paper, paperboard, and other related products. Despite the economic importance of the industry that is founded on the conversion of the lignocellulosic content of wood into paper, the basic processes for delignifying wood, or significantly reducing its lignin content, for papermaking apply to all processes for which the purpose is to enhance the value or utility of a lignocellulosic material by modification of or reduction of its lignin content.
For use in paper-making processes, wood must first be reduced to pulp, which can be defined as wood fibers capable of being slurried or suspended and then deposited on a screen to form a sheet. The methods used to accomplish this pulping usually involve either a physical or chemical treatment of the wood or perhaps some combination of the two processes, to alter its physical and chemical form to give the desired paper properties.
Current industrial processes for pulping wood and other sources of lignocellulosic material such as annual plants, and for bleaching the resultant pulp, have evolved slowly over many decades. Although these processes are quite complex and energy-intensive, they are relatively efficient. Their major disadvantage is that the chemical processes involved have the capacity to create a negative impact on the environment. Even the best of current technology is unable to completely suppress the odors emitted by pulp mills, or to completely eliminate the emission of chlorinated organic compounds from waste treatment plants associated with pulp mill bleach plants. The discovery of new methods for more easily or more effectively modifying or delignifying wood such as those disclosed herein can lead to the development of new, more efficient, less environmentally troublesome pulping and bleaching processes.
Pulping is achieved by chemical or mechanical means or combinations of the two. In mechanical pulping, the original constituents of the fibrous material are essentially unchanged, except for the removal of water soluble constituents. Chemical pulping, in contrast, has as its purpose the selective removal of the fiber-bonding lignin to a varying degree, while minimizing the degradation and dissolution of the hemicelluloses and cellulose. If the ultimate purpose of the pulp is the preparation of white papers, the purification process begun through initial pulping is continued in subsequent bleaching steps. The bleaching process can result not only in a brightening of the resulting pulp, but also a further reduction in the lignin content of the pulp. The properties of the end products of the pulping/bleaching process such as, for example, papers and paperboards, will be determined largely by the properties of the pulps that are used in their manufacture. The properties of the pulps, in turn, are determined by the particular pulping processes employed, as well as the identity of the wood species or non-wood plant fiber lignocellulosic used as the raw material for the pulp.
A pulp produced solely by chemical methods is referred to as a full chemical pulp. In practice, chemical pulping methods are successful in removing most of the lignin; they also degrade a certain amount of the hemicellulose and cellulose so that the yield of pulp is low relative to mechanical pulping, usually between 40 and 50% of the original wood substance, with a residual lignin content on the order of 3-5%. These pulps can be characterized as high strength pulps, although their production can be costly both in terms of the consumption of chemicals in the process, as well as the loss of hemicellulose and cellulose content from the starting materials.
In typical chemical pulping, wood physically reduced to a chip form is cooked with the appropriate chemicals in an aqueous solution, generally at elevated temperature and pressure. The energy and other process costs associated with reaction processes at elevated temperatures and pressures constitute significant disadvantages for conventional pulping processes. The two principal methods are the (alkaline) kraft process and the (acidic) sulfite process. The kraft process has come to occupy the dominant position because of advantages in chemical recovery and pulp strength. The sulfite process was more common up to 1930, before the advent of the widespread use of the kraft process, although its use has increased somewhat in recent years.
The kraft process involves cooking wood chips in a solution of sodium hydroxide (NaOH) and sodium sulfide (Na 2 S). The alkaline attack causes a breaking of the lignin molecule into smaller segments whose sodium salts are soluble in the cooking liquor. Kraft pulps produce strong paper products ("kraft" is the German word for strength), but the unbleached pulp is characterized by a dark brown color. The kraft process is associated with malodorous gases, principally organic mercaptans and sulfides, which cause environmental concern, to which anyone who has been in the olfactory proximity of a kraft pulp mill can attest.
The kraft process evolved over 100 years ago from soda cooking (which utilizes only sodium hydroxide as the active chemical), when Carl S. Dahl, a German chemist, introduced sodium sulfate into the chemical cooking system as a makeup chemical. Actual conversion to sodium sulfide (Na 2 S) in the resultant cooking liquor produced a dramatic improvement in reaction kinetics and pulp properties when cooking softwoods. The fact that sodium sulfate is commonly used as a makeup chemical is the reason that the kraft process is sometimes called the "sulfate process". The process uses the combination of sodium hydroxide and sodium sulfide at a pH in excess of 12, at 160-180° C. (320°-356° F.), corresponding to about 800 kPa (120 psi) steam pressure, for 0.5-3 hours to degrade and dissolve much of the lignin of the wood fibers. The comparative strength of the resulting pulp arises from the use of an alkaline sulfide solution and the shorter cooking times which, in turn, lead to less cellulose degradation. Despite a certain number of distinct disadvantages, not the least of which are the energy costs imposed by typical reaction conditions, about 75-80% of U.S. virgin pulp is produced by this process.
In the alternative sulfite process, a mixture of sulfurous acid (H 2 SO 3 ) and bisulfite ion (HSO 3 -) is used to attack and solubilize the lignin component of the lignocellulosic starting material. Here, the mechanism of chemical attack removes the lignin as salts of lignosulfonic acid, and the molecular structure, although fragmented, is left largely intact. The cations for the bisulfite can be calcium, magnesium, sodium, or ammonium. Sulfite pulping can be carried out over a wide range of pH. "Acid sulfite" denotes pulping with an excess of free sulfurous acid (pH 1-2), while "bisulfite" cooks are carried out under less acidic conditions (pH 3-5).
Sulfite pulps are lighter in color than kraft pulps and can be bleached more easily, but the paper sheets are weaker than equivalent kraft sheets. The sulfite process works well for such softwoods as spruce, fir and hemlock, and such hardwoods as poplar and eucalyptus; but resinous softwoods and tannin-containing hardwoods are more difficult to handle. This sensitivity to wood species, along with the weaker pulp strength and the greater difficulty in chemical recovery, are the major reasons for the decline of sulfite pulping relative to kraft. The trend towards whole tree chipping puts sulfite at a further disadvantage because of its intolerance to bark.
Although all delignification or chemical pulping processes have as their desired end result the significant reduction of the lignin content of the starting lignocellulosic material, the characteristics of the individual processes chosen to achieve that end bear considerably on the properties of the resulting products manufactured from that pulp. In general, although the chemical goal of pulping or delignification processes is the separation of the fibrous carbohydrate content of the lignocellulosic material from the lignin content, it is not always possible or even desirous to remove the entire lignin component from the lignocellulosic starting material. The extent to which any chemical pulping process is capable of degrading and solubilizing the lignin component of a lignocellulosic material while minimizing the accompanying degradation of cellulose and hemicellulose is referred to as the "selectivity" of the process.
Delignification selectivity is an important consideration during pulping and bleaching operations where it is desired to maximize removal of the lignin while retaining as much cellulose and hemicellulose as possible. One way of defining delignification selectivity in a quantitative fashion is as the ratio of lignin removal to carbohydrate removal during the delignification process. Although this ratio is seldom measured directly, it is measured in a relative manner by yield versus Kappa Number plots. Although the slope of two plots corresponding to two different pulping or delignification processes may be the same, the process which produces a higher yield, as measured by the amount of pulp in comparison to the amount of the starting material, for the same degree of delignification is considered to be the more selective process. A high selectivity alone, however, does not mean that pulp "A" is better than "B" since such plots do not indicate the strength or the viscosity of the pulp. For example, acid sulfite pulping is, by this definition more selective than kraft pulping; however, acid sulfite pulp is weaker than kraft pulp because the cellulose fibers are weaker due to acid hydrolysis.
Another way of defining selectivity is as the viscosity of the pulp at a given low lignin content. This is usually done by plotting pulp viscosity versus Kappa Number and comparing the viscosities of the pulps at a selected Kappa Number. The higher the viscosity, the more selective the delignification, or pulping process. In general, for a given process, the higher the viscosity the stronger the pulp. This sometimes does not apply when comparing pulps produced by different processes. For example, for a given low lignin content, acid sulfite pulp will be higher in yield and in pulp viscosity than kraft pulp; however, the kraft pulp will have higher strength properties.
In the sulfite process, sulfonation and acid hydrolysis contribute to delignification, and acid hydrolysis to carbohydrate degradation and dissolution. In the kraft process, mercaptation (sulfidation) and alkaline hydrolysis contribute to delignification, and alkaline peeling and hydrolysis to the carbohydrate degradation. The delignification proceeds more rapidly in the sulfite cook than in the kraft cook, and lower temperatures can therefore be used in the former, which is fortunate because the hydrolysis of the glycosidic bonds of the carbohydrates occurs much more rapidly in acidic than in alkaline medium. Alkaline peeling reactions, on the other hand, require lower temperature than the alkaline delignification, and they unavoidably decrease the carbohydrate yield, to a degree which depends on both chemical and physical changes in their structure. Accessibility phenomena improve the selectivity of lignin removal, partly because in the early stages of the cook the morphological structure protects the carbohydrates from being attacked by the pulping chemicals, especially in the sulfite cook, and partly because some of the hemicelluloses are capable of rearrangements to a more ordered and less accessible structure during the cook. The net result of all these phenomena is that softwood pulp yields at a certain degree of delignification are about 3-5% of the wood higher for the sulfite than for the kraft process, whereas hardwood pulp yield are fairly similar.
The methods described above for the delignification or pulping of lignocellulosic materials, although each possess certain practical advantages, can all be characterized as being hampered by significant disadvantages. Thus, there exists a need for delignification or pulping processes which are advantageous economically, either in terms of cellulosic yield of the process or in terms of the chemical or process technology costs of the method; which are environmentally benign; which produce delignified materials of superior properties; and which are applicable to a wide variety of lignocellulosic materials. Such processes, as exemplified by the invention disclosed herein, have the added advantage of wide applicability well beyond the area of pulping.
SUMMARY OF THE INVENTION
Lignocellulosics such as wood, straw, sugar cane bagasse, reeds, kenaf, corn stover, flax and wood in various forms of separation or preparation, such as fiberized wood, wood meal, destructured wood chips or wood chips physically or chemically treated to enhance their porosity, can be effectively and, when desired, almost totally delignified by peroxymonophosphoric acid in solutions ranging from neutral or very mildly acidic, to strongly acidic. Even under strongly acidic conditions, a delignified residue with high viscosity, good strength properties, and high brightness can be obtained.
Therefore, in one aspect, the present invention provides a method of oxidatively treating a lignocellulosic material to decrease a content of lignin therein, the method comprising the steps of contacting the lignocellulosic material with a solution of peroxymonophosphoric acid at a temperature and for a time effective to substantially fragment the lignin; separating a solid residue from the solution; and extracting the lignin fragments from the residue. The lignocellulosic material treated according to the present invention is selected from the group consisting of wood, straw, sugar cane bagasse, reeds, corn stover, flax and prepared wood material. More preferably, the prepared wood material treated according to the present invention comprises porosity-enhanced wood chips, fiberized wood, chemical wood pulp, high yield pulp, waste paper, or recycled fibers.
In another aspect, practice of the method of the present invention occurs at a temperature in the range of 273K to 473K. Preferably, the temperature is in the range of 293K to 353K. In addition, according to the practice of the method of the invention, the lignocellulosic material is in contact with the solution of peroxymonophosphoric acid from about 0.1 to about 1200 hours. Preferably, the lignocellulosic material is in contact with the solution of peroxymonophosphoric acid from about 1 to about 600 hours. According to the method of the present invention, the concentration of peroxymonophosphoric acid in the solution contacting the lignocellulosic material is from about 0.1 to about 20 mass percent. Preferably, the concentration of peroxymonophosphoric acid is from about 1.0 to about 5.0 mass percent. According to this aspect of the invention, the pH of the peroxymonophosphoric acid solution used in the practice of the present invention is in the range of -0.5 to 7 pH units. Preferably, the pH of the peroxymonophosphoric acid solution is in the range of -0.3 to 5.0 pH units. Furthermore, according to the present invention, the peroxymonophosphoric acid solution to lignocellulosic material mass ratio is in the range of from 1:1 to 100:1. Preferably, the peroxymonophosphoric acid solution to lignocellulosic material mass ratio is in the range of from 2:1 to 50:1.
In another aspect of the present invention, the lignin extraction is carried out by a dilute alkaline solution. Preferably, the alkaline solution is a solution of sodium hydroxide or potassium hydroxide. Alternatively, the lignin extraction is carried out by a solution of ammonium hydroxide. More preferably, the method of the claimed invention comprises the additional steps of collecting liquors from the peroxymonophosphoric acid treatment step and from the lignin extraction step and applying these liquors as a fertilizer to appropriate crops and/or arable or forest land.
According to the method of the claimed invention, the lignin content of the lignocellulosic material can be decreased by about 5 to about 99 percent. Preferably, according to the method of the invention, the lignin content of the lignocellulosic material will be decreased by at least 30 percent. More preferably, the lignin content of the lignocellulosic material is decreased by at least 60 percent. More preferably still, the lignin content of the lignocellulosic material treated according to the method of the present invention is decreased by at least 90 percent.
In another aspect, the method of the claimed invention comprises the additional step of contacting the lignocellulosic material to be treated with a strongly acidic solution, or a solution of a metal chelating agent, draining the solution, and thoroughly washing with water prior to contacting the lignocellulosic material with the peroxymonophosphoric acid solution. Alternatively, the method of the claimed invention comprises the additional step of contacting the lignocellulosic material with a strongly alkaline solution prior to contacting the lignocellulosic material with the peroxymonophosphoric acid solution. In yet another aspect, the method of the invention comprises the additional step of first contacting the lignocellulosic material with a strongly alkaline solution prior to contacting the material with a strongly acidic solution, or a solution of a metal chelating agent, followed by draining, and thoroughly washing with water. In an alternative aspect, the present invention contemplates a method comprising the further step of bleaching the delignified residue.
In another embodiment, the present invention provides a method of oxidatively treating chemical pulps prepared by industry standard pulping processes, with the purpose of decreasing the lignin content of the pulp, and wherein the method improves the optical brightness of the pulp. According to this embodiment, the method comprises the steps of contacting the pulp with a solution of peroxymonophosphoric acid at a temperature and for a time effective to substantially fragment the lignin; separating a solid residue from the solution; and extracting the fragmented lignin from the residue. The method of the invention further contemplates that the bleached pulp would have an International Standard Organization (ISO) brightness of at least 40. Also contemplated by the claimed invention is a method comprising a further step of bleaching the delignified pulp. The method further provides that the pulp, treated according to the practice of the invention, would have an ISO brightness of at least 60 after the bleaching step.
In another aspect, practice of this alternative embodiment of the claimed invention occurs at a temperature in the range of 273K to 473K. Preferably, the temperature is in the range of 293K to 353K. In addition, according to the method of the invention, the pulp is in contact with the solution of peroxymonophosphoric acid from about 0.1 to about 1200 hours. Preferably, the pulp is in contact with the solution of peroxymonophosphoric acid from about 1 to about 600 hours. According to the method of the present invention, the concentration of peroxymonophosphoric acid in the solution contacting the pulp is from about 0.1 to about 20 mass percent. Preferably, the concentration of peroxymonophosphoric acid is from about 1.0 to about 5.0 mass percent. According to this embodiment of the invention, the pH of the peroxymonophosphoric acid solution used in the method of the invention is in the range of -0.5 to 7 pH units. Preferably, the pH of the peroxymonophosphoric acid solution is in the range of -0.3 to 5.0 pH units. Furthermore, according to this embodiment of the invention, the peroxymonophosphoric acid solution to chemical pulp mass ratio is in the range of from 1:1 to 100:1. Preferably, the peroxymonophosphoric acid solution to pulp mass ratio is in the range of from 2:1 to 50:1.
In another aspect of the present invention, the lignin extraction step of the method of the invention is carried out by a dilute alkaline solution. Preferably, the alkaline solution is a solution of sodium hydroxide or potassium hydroxide. Alternatively, the lignin extraction is carried out by a solution of ammonium hydroxide. More preferably, the method of the claimed invention comprises the additional steps of collecting liquors from the peroxymonophosphoric acid treatment step and from the lignin extraction step and applying these liquors as a fertilizer to appropriate crops and/or arable or forest land.
In the practice of this embodiment of the claimed invention, the lignin content of the chemical pulp can be decreased by about 5 to about 99 percent. Preferably, the lignin content of the pulp will be decreased by at least 30 percent. More preferably, the lignin content is decreased by at least 60 percent. More preferably still, the lignin content of the chemical pulp treated according to this embodiment of the claimed invention is decreased by at least 90 percent.
In another aspect, the method of the claimed invention comprises the additional step of contacting the chemical pulp to be treated with a strongly acidic solution, or a solution of a metal chelating agent, draining the solution, and thoroughly washing with water prior to contacting the pulp with the peroxymonophosphoric acid solution. Alternatively, the method of the claimed invention comprises the additional step of contacting the pulp with a strongly alkaline solution prior to contacting the pulp with the peroxymonophosphoric acid solution. In yet another aspect, the method of the invention comprises the additional step of first contacting the pulp with a strongly alkaline solution prior to contacting the material with a strongly acidic solution, or a solution of a metal chelating agent, followed by draining and thoroughly washing with water. In an alternative aspect, the present invention contemplates a method comprising the further step of bleaching the delignified pulp.
In an alternative embodiment, the present invention provides a method of oxidatively degrading the lignin component of a lignocellulosic material comprising contacting the lignocellulosic material with an solution of peroxymonophosphoric acid under conditions of temperature, time, and pH effective to degrade the lignin component. The lignocellulosic material treated according to this embodiment of present invention is selected from the group consisting of wood, straw, sugar cane bagasse, kenaf, reeds, corn stover, flax, prepared wood material, livestock fodder, and organic material of plant origin. Thus, the digestibility of such lignocellulosic material will be improved significantly.
In another aspect, practice of the method of this embodiment of the invention occurs at a temperature in the range of 273K to 473K. Preferably, the temperature is in the range of 293 K to 353K. In addition, according to the practice of the method of the invention, the lignocellulosic material is in contact with the solution of peroxymonophosphoric acid from about 0.1 to about 1200 hours. Preferably, the lignocellulosic material is in contact with the solution of peroxymonophosphoric acid from about 1 to about 600 hours. According to the method of the present invention, the concentration of peroxymonophosphoric acid in the solution contacting the lignocellulosic material is from about 0.1 to about 20 mass percent. Preferably, the concentration of peroxymonophosphoric acid is from about 1.0 to about 5.0 mass percent. According to this aspect of the invention, the pH of the peroxymonophosphoric acid solution used in the practice of the present invention is in the range of -0.5 to 7 pH units. Preferably, the pH of the peroxymonophosphoric acid solution is in the range of -0.3 to 5.0 pH units. Furthermore, according to the present invention, the peroxymonophosphoric acid solution to lignocellulosic material mass ratio is in the range of from 1:1 to 100:1. Preferably, the peroxymonophosphoric acid solution to lignocellulosic material mass ratio is in the range of from 2:1 to 50:1.
In another aspect, the method of the claimed invention comprises the additional step of contacting the lignocellulosic material to be treated with a strongly acidic solution, or a solution of a metal chelating agent, draining the solution and thoroughly washing with water prior to contacting the lignocellulosic material with the peroxymonophosphoric acid solution. Alternatively, the method of the claimed invention comprises the additional step of contacting the lignocellulosic material with a strongly alkaline solution prior to contacting the lignocellulosic material with the peroxymonophosphoric acid solution. In yet another aspect, the method of the invention comprises the additional step of first contacting the lignocellulosic material with a strongly alkaline solution prior to contacting the material with a strongly acidic solution, or a solution of a metal chelating agent, followed by a thorough washing with water.
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment comprising a range of conditions is provided under A, below. In a broader embodiment of this invention, lignin is removed from lignocellulosics using an aqueous delignifying solution comprising peroxymonophosphoric acid according to the set of conditions listed below under B.
______________________________________ A. PREFERRED B. RANGE OF EMBODIMENT EMBODIMENT______________________________________pH -0.3 to 4.3 -0.5 to 7H.sub.3 PO.sub.5 % IN SOLUTION 1.0 to 5.0 0.1 to 20LIQUOR TO LIGNO- 2:1 to 50:1 1:1 to 100:1CELLULOSE RATIOTIME, HRS. 1 to 600 0.1 to 1200TEMPERATURE, °C. 20 to 80 0 to 200______________________________________
All types of lignocellulosic materials can be delignified by this method. By way of example, and without limitation, lignin can be removed from both light weight and dense hardwoods and softwoods, and from all kinds of non-woody species. Illustrative of these non-woody materials, without limitation, are grasses, cereal straws, bamboo, cornstalks, sugar cane bagasse, kenaf, hemp, jute, sisal, esparto, reeds and the like.
Organic peroxides, such as peracetic and performic acids, have been known to readily delignify wood and other lignocellulosic materials. With the exception of attention directed to the use of alkaline hydrogen peroxide, little attention has been directed toward the delignification of lignocellulosic materials with inorganic peroxides. Alkaline hydrogen peroxide can remove some lignin from lignocellulosics but, in general, it is quite ineffective in delignification. It has been determined that dilute solutions of the peroxymonosulfate anion, under acidic conditions and at low temperature (20°-50° C.) and atmospheric pressure, can be effective in delignification of wood. Such peroxymonosulfate treatment must be followed by an alkaline extraction to solubilize and remove the fragments of depolymerized lignin.
The present invention concerns the use of peroxymonophosphoric acid in place of organic peracids. The use of peroxymonophosphates in such fashion has not been previously suggested, nor have they been used in a way which would suggest to a pulp and paper chemist that peroxymonophosphates would perform in the pulping and bleaching of lignocellulosic materials in a fashion similar to that of organic peracids, or for that matter, that they may be employed under non-extreme conditions in the treatment of cellulose containing materials to assist in and improve the separation of non-cellulosic materials therefrom.
In the oxidative reaction of peroxymonophosphoric acid, H 3 PO.sub., with lignin in lignocellulosics to degrade the lignin or to delignify the lignocellulosic material, yielding a cellulose-enriched pulp, comparatively very little oxidant is used. This then makes possible the ready delignification of reduced-lignin chemical pulps in either a subsequent bleaching or a pre-bleaching treatment process. Such treatment yields very low lignin levels in the pulps so they can be efficiently and more effectively brightened to high levels. Such processes also open the path for the treatment of porosity-enhanced wood chips, fiberized wood, high yield pulps, waste papers, recycled fibers and the like to enhance their properties, and thus their utilization. The peroxymonophosphoric acid treatment process of the present invention further opens the door to an economical method for delignifying lignocellulosics from agricultural and forest residues to enhance the enzymatic and ruminant digestibility of the residues.
In one aspect, the present invention provides a method of oxidatively treating a lignocellulosic material to decrease a content of lignin therein, the method comprising the steps of contacting the lignocellulosic material with a solution of peroxymonophosphoric acid at a temperature and for a time effective to substantially fragment the lignin; separating a solid residue from the solution; and extracting the lignin fragments from the residue. The lignocellulosic material treated according to the present invention is selected from the group consisting of wood, straw, sugar cane bagasse, kenaf, reeds, corn stover, flax and prepared wood material. More preferably, the prepared wood material treated according to the present invention comprises porosity-enhanced wood chips, fiberized wood, chemical wood pulp, high yield pulp, waste paper, or recycled fibers.
If wood is the lignocellulosic material to be delignified, it is preferable to use a pre-treatment to increase its permeability or, in the alternative, to use wood fiber, wood meal or destructured wood. Untreated wood chips are not easily penetrated by aqueous acidic solutions, and oxidizing agents produce a topochemical effect with chips because oxidant is consumed by lignin as it moves from the outside fibers inward. Unpre-treated wood chips may, however, be employed under conditions in which the outer reacted fibers are separate d from the chips and liquor during the digestion period.
Wood chips are not easily penetrated by acidic solutions. Also, heterogeneous pulping of chips is often observed with oxidizing reagents because high reactivity with lignin consumes oxidant as the liquor progresses from the outside fibers inward. More rapid, uniform reaction may be promoted by starting with a high-yield fiber or destructured chips. Wood fibers may be obtained in a relatively undamaged form by thermal softening of the middle lamella lignin and mechanically fiberizing. The lignin-coated fibers thus obtained are used commercially to produce hardboard and are referred to as hardboard fibers.
In another aspect, practice of the method of the present invention occurs at a temperature in the range of 273K to 473K. Preferably, the temperature is in the range of 293K to 353K. In addition, according to the practice of the method of the invention, the lignocellulosic material is in contact with the solution of peroxymonophosphoric acid from about 0.1 to about 1200 hours. Preferably, the lignocellulosic material is in contact with the solution of peroxymonophosphoric acid from about 1 to about 600 hours. According to the method of the present invention, the concentration of peroxymonophosphoric acid in the solution contacting the lignocellulosic material is from about 0.1 to about 20 mass percent. Preferably, the concentration of peroxymonophosphoric acid is from about 1.0 to about 5.0 mass percent. According to this aspect of the invention, the pH of the peroxymonophosphoric acid solution used in the practice of the present invention is in the range of -0.5 to 7 pH units. Preferably, the pH of the peroxymonophosphoric acid solution is in the range of -0.3 to 5.0 pH units. Furthermore, according to the present invention, the peroxymonophosphoric acid solution to lignocellulosic material mass ratio is in the range of from 1:1 to 100:1. Preferably, the peroxymonophosphoric acid solution to lignocellulosic material mass ratio is in the range of from 2:1 to 50:1.
The discovery of the delignifying ability of peroxymonphosphate solutions across a wide range of pH makes possible a broad spectrum of potential end-uses for these solutions in pulping and bleaching. Such solutions can be used to treat wood or other lignocellulosics to produce chemical-type pulps or to treat mechanical, thermomechanical, chemimechanical, or chemithermomechanical pulps to improve their strength properties. These solutions can be used to restore or improve the strength of secondary fiber from unbleached softwood kraft wastepaper, old corrugated containers, or old newsprint. Peroxymonophosphate can also be used as a replacement for chlorine and chlorine dioxide in pulp bleaching or as a pretreatment prior to oxygen delignification or bleaching.
In another aspect of the present invention, the lignin extraction is carried out by a dilute alkaline solution. Preferably, the alkaline solution is a solution of sodium hydroxide or potassium hydroxide. Alternatively, the lignin extraction is carried out by a solution of ammonium hydroxide. More preferably, the method of the claimed invention comprises the additional steps of collecting liquors from the peroxymonophosphoric acid treatment step and from the lignin extraction step and applying these liquors as a fertilizer to appropriate crops and/or arable or forest land.
Spent treating liquor from peroxymonophosphate delignification can contain a large amount of acid together with some degraded lignin fragments and carbohydrate fragments. However, most lignin and carbohydrate fragments would be in the alkaline extraction liquor. As is possible for nitric acid pulping, the treating liquor can be recycled back to the treating stage, and reinforced with fresh peroxymonophosphate several times before disposal. After several uses, the liquor could be neutralized with spent extraction liquor and used as a fertilizer.
Alternative means may be used to dispose of the spent extraction liquor. If the extraction is performed using sodium hydroxide, the spent extraction liquor can be evaporated and burned as in the kraft recovery cycle. However, this process requires multistage evaporators and a recovery furnace, a very large capital expense. If the extraction is performed using ammonium hydroxide or potassium hydroxide, the spent extraction liquors can be used as fertilizer. Ammonium hydroxide extraction liquors from nitric acid pulping have been shown to have no deleterious effects on plant growth and to act as an effective fertilizer.
Through the use of ammonium hydroxide or potassium hydroxide in the extraction stage and the subsequent use of spent extraction liquor as a fertilizer, the peroxymonophosphate delignification method is relatively low cost and much more environmentally compatible than the kraft process. The spent extraction liquors mixed with, and thus used to neutralize, the initial treating liquors can be spread on farm fields or in forests.
According to the method of the claimed invention, the lignin content of the lignocellulosic material can be decreased by about 5 to about 99 percent. Preferably, according to the method of the invention, the lignin content of the lignocellulosic material will be decreased by at least 30 percent. More preferably, the lignin content of the lignocellulosic material is decreased by at least 60 percent. More preferably still, the lignin content of the lignocellulosic material treated according to the method of the present invention is decreased by at least 90 percent.
In another aspect, the method of the claimed invention comprises the additional step of contacting the lignocellulosic material to be treated with a strongly acidic solution, or a solution of a metal chelating agent such as (ethylenediaminetetraacetic acid) EDTA, (diethylenetriaminepentaacetic acid) DTPA or (diethylenetriaminepentamethylene phosphoric acid) DTMPA, draining the solution and thoroughly washing with water prior to contacting the lignocellulosic material with the peroxymonophosphoric acid solution. Alternatively, the method of the claimed invention comprises the additional step of contacting the lignocellulosic material with a strongly alkaline solution prior to contacting the lignocellulosic material with the peroxymonophosphoric acid solution. In yet another aspect, the method of the invention comprises the additional step of first contacting the lignocellulosic material with a strongly alkaline solution prior to contacting the material with a strongly acidic solution or a solution of a metal chelating agent, followed by thorough washing.
The practice of the present invention contemplates the use of strongly acidic solution in the pretreatment of lignocellulosics prepared from strong mineral acids such as, by way of example and without limitation, sulfuric acid or nitric acid. As would be understood by one of skill in the appropriate chemical arts, it would also be possible to prepare a strongly acidic pre-treating solution from a limited number of organic acids in addition to the mineral acids discussed immediately above. However, such acids would have to be chosen by their ability to dissociate in solution resulting in a sufficiently high concentration of acidic protons relative to the concentration of undissociated acid molecules. In an analogous fashion, strongly basic solutions used for pretreatment of lignocellulosics, either alone or in combination with strongly acidic solutions, are contemplated to be prepared from typical strongly alkaline species such as sodium hydroxide (NaOH) or potassium hydroxide (KOH). However, any species capable of producing a sufficiently high pH in solution would be appropriate provided that there would be no significant prospect for participating in potentially competing or interfering side reactions deleterious to the pretreatment or delignification processes. In an alternative aspect, the present invention contemplates a method comprising the further step of bleaching the delignified residue.
In another embodiment, the present invention provides a method of oxidatively treating chemical pulps prepared by industry standard pulping processes, with the purpose of decreasing the lignin content of the pulp, and wherein the method improves the optical brightness of the pulp. According to this embodiment, the method comprises the steps of contacting the pulp with a solution of peroxymonophosphoric acid at a temperature and for a time effective to substantially fragment the lignin; separating a solid residue from the solution; and extracting the fragmented lignin from the pulp. The method of the invention further contemplates that the treated pulp would have an ISO brightness of at least 40. Also contemplated by the claimed invention is a method comprising a further step of bleaching the delignified pulp. The method further provides that the pulp, treated according to the practice of the invention, would have an ISO brightness of at least 60 after the bleaching step.
The use of peroxymonophosphate for at least partial delignification and bleaching of pulps and other delignification residues can greatly reduce the quantity of chlorinated organics and of dioxins and dibenzofurans in effluent. Because no halogens are present in the spent liquor from the initial stage or in the liquor from the following alkaline extraction stage, these liquors can be sent to chemical recovery.
Peroxymonophosphate can be used to replace the chlorine dioxide stages in bleaching. The replacement of both chlorination and chlorine dioxide stages through use of peroxymonophosphate means that all spent liquors from a bleach plant can be sent to chemical recovery with no environmentally troublesome materials emerging from the bleach plant. The bleach plant is currently the major source of effluents from a bleached kraft pulp mill that require subsequent treatment to render them relatively environmentally benign.
Oxidative pre-treatments of unbleached softwood kraft pulps prior to oxygen delignification generally allow greater lignin removal in the oxygen stage before serious pulp strength loss occurs. In this vein, it has been shown that oxidating agents such as chlorine, chlorine dioxide, and nitrogen dioxide can be effective in pretreatment. Peroxymonphosphate can also be used in such pretreatment. The advantages of peroxymonophosphate are that it contains no halogens and that it can be used in solution, unlike nitrogen dioxide. Peroxymonophosphate pretreatment makes it possible to reduce lignin to a level as low as 1 percent in the subsequent oxygen stage before serious strength loss occurs.
In another aspect, practice of this alternative embodiment of the claimed invention occurs at a temperature in the range of 273K to 473K. Preferably, the temperature is in the range of 293K to 353K. In addition, according to the method of the invention, the pulp is in contact with the solution of peroxymonophosphoric acid from about 0.1 to about 1200 hours. Preferably, the pulp is in contact with the solution of peroxymonophosphoric acid from about 1 to about 600 hours. According to the method of the present invention, the concentration of peroxymonophosphoric acid in the solution contacting the pulp is from about 0.1 to about 20 mass percent. Preferably, the concentration of peroxymonophosphoric acid is from about 1.0 to about 5.0 mass percent. According to this embodiment of the invention, the pH of the peroxymonophosphoric acid solution used in the method of the invention is in the range of -0.5 to 7 pH units. Preferably, the pH of the peroxymonophosphoric acid solution is in the range of -0.3 to 5.0 pH units. Furthermore, according to this embodiment of the invention, the peroxymonophosphoric acid solution to chemical pulp mass ratio is in the range of from 1:1 to 100:1. Preferably, the peroxymonophosphoric acid solution to pulp mass ratio is in the range of from 2:1 to 50:1.
In another aspect of the present invention, the lignin extraction step of the method of the invention is carried out by a dilute alkaline solution. Preferably, the alkaline solution is a solution of sodium hydroxide or potassium hydroxide. Alternatively, the lignin extraction is carried out by a solution of ammonium hydroxide. More preferably, the method of the claimed invention comprises the additional steps of collecting liquors from the peroxymonophosphoric acid treatment step and from the lignin extraction step and applying these liquors as a fertilizer to appropriate crops and/or arable or forest land.
In the practice of this embodiment of the claimed invention, the lignin content of the chemical pulp can be decreased by about 5 to about 99 percent. Preferably, the lignin content of the pulp will be decreased by at least 30 percent. More preferably, the lignin content is decreased by at least 60 percent. More preferably still, the lignin content of the chemical pulp treated according to this embodiment of the claimed invention is decreased by at least 90 percent. In another aspect, the method of the claimed invention comprises the additional step of contacting the chemical pulp to be treated with a strongly acidic solution, or a solution of a chelating agent such as EDTA or DTPA, draining the solution and thoroughly washing with water prior to contacting the pulp with the peroxymonophosphoric acid solution.
In an alternative embodiment, the present invention provides a method of oxidatively degrading the lignin component of a lignocellulosic material comprising contacting the lignocellulosic material with an solution of peroxymonophosphoric acid under conditions of temperature, time, and pH effective to degrade the lignin component. The lignocellulosic material treated according to this embodiment of present invention is selected from the group consisting of wood, straw, sugar cane bagasse, kenaf,reeds, corn stover, flax, prepared wood material, livestock fodder, and organic material of plant origin.
Although across the world a great quantity of plant organic material is regularly produced, a significant portion of that organic material has little use nor value today. Substantially all plant organic material includes the combination of cellulose and lignin in various compositions and structural arrangements. The lignocellulose material is digestible at varying efficiencies by different animals. For instance, grass is a lignocellulosic material, the cellulose content of which is readily digestible by ruminants. Humans, however, cannot digest grass at a sufficiently high level to maintain body weight and therefore must depend upon a higher order of digestible organic material, such as grain. Other animals, such as beavers, can successfully digest lignocellulose, like tree bark, at a sufficient rate to maintain growth, whereas agricultural livestock such as cattle, sheep, horses and swine, cannot subsist on a diet of tree bark. Even among agricultural animals, the digestive systems vary to an extent wherein cattle and other ruminants can effectively utilize plant organic material having a lignocellulosic composition which will not be useful for horses or swine.
The human population continues to grow at such a rate that the grain producing potential of the world is becoming overtaxed. Furthermore, the diversion of grain to agricultural animals to produce meat results in a net calorie loss in terms of human food consumption. This threat of possible famine exists in spite of a huge quantity of plant organic material in the forests and jungles of the world. If the digestibility of plant organic material can be increased significantly, then forests and jungles can produce sufficient food for the world's increasing population. Lignin degradation with peroxymonophosphoric acid, with or without subsequent extraction, increases the digestibility of such plant organic matter.
In another aspect, practice of the method of this embodiment of the invention occurs at a temperature in the range of 273K to 473K. Preferably, the temperature is in the range of 293K to 353K. In addition, according to the practice of the method of the invention, the lignocellulosic material is in contact with the solution of peroxymonophosphoric acid from about 0.1 to about 1200 hours. Preferably, the lignocellulosic material is in contact with the solution of peroxymonophosphoric acid from about 1 to about 600 hours. According to the method of the present invention, the concentration of peroxymonophosphoric acid in the solution contacting the lignocellulosic material is from about 0.1 to about 20 mass percent. Preferably, the concentration of peroxymonophosphoric acid is from about 1.0 to about 5.0 mass percent. According to this aspect of the invention, the pH of the peroxymonophosphoric acid solution used in the practice of the present invention is in the range of -0.5 to 7 pH units. Preferably, the pH of the peroxymonophosphoric acid solution is in the range of -0.3 to 5.0 pH units. Furthermore, according to the present invention, the peroxymonophosphoric acid solution to lignocellulosic material mass ratio is in the range of from 1:1 to 100:1. Preferably, the peroxymonophosphoric acid solution to lignocellulosic material mass ratio is in the range of from 2:1 to 50:1.
According to the method of this embodiment of the claimed invention, the lignin content of the lignocellulosic material can be decreased by about 5 to about 99 percent. Preferably, according to the method of the invention, the lignin content of the lignocellulosic material will be decreased by at least 30 percent. More preferably, the lignin content of the lignocellulosic material is decreased by at least 60 percent. More preferably still, the lignin content of the lignocellulosic material treated according to the method of the present invention is decreased by at least 90 percent.
In another aspect, the method of the claimed invention comprises the additional step of contacting the lignocellulosic material to be treated with a strongly acidic solution, or a solution of a metal chelating agent, draining the solution and thoroughly washing with water prior to contacting the lignocellulosic material with the peroxymonophosphoric acid solution. Alternatively, the method of the claimed invention comprises the additional step of contacting the lignocellulosic material with a strongly alkaline solution prior to contacting the lignocellulosic material with the peroxymonophosphoric acid solution. In yet another aspect, the method of the invention comprises the additional step of first contacting the lignocellulosic material with a strongly alkaline solution prior to contacting the material with a strongly acidic solution, or a solution of a metal chelating agent, draining the solution and thoroughly washing with water.
EXAMPLES
Examples of delignification with peroxymonophosphate are given below:
Example 1
Delignification of Aspen Wood without Pretreatment.
Run 1
Peroxymonophosphoric acid was prepared as follows: 1.25 g of potassium peroxydiphosphate was dissolved in 26.3 g distilled, reverse-osmosis water, and 7.5 g of 70% nitric acid was added. This mixture was reacted in a 50° C. water bath for 30 minutes, and then cooled, yielding a solution containing 1.0% peroxymonophosphoric acid. The solution was analyzed using the art-recognized method of Greenspan, F. P. and MacKellar, D. G., Analytical Chemistry 20 (11): 106 (1948).
Aspen wood meal, 1.07 g air dried (5.9% moisture) which passed through a 40-mesh screen, was mixed with 25.1 g of the above solution and held at room temperature (22° C.) for 16 hours. The mixture was then filtered using a sintered glass crucible and the filtrate analyzed for peroxymonophosphoric acid as above. The solid residue was mixed with 1% sodium hydroxide solution at 50° C., and held for 20 minutes. This was repeated three times, and then the residue was filtered and washed with reverse-osmosis water until the water displayed a neutral pH. The residue was finally vacuum oven dried at 60° C. for 16 hours, weighed and analyzed. Results for this Run and for all other runs of Example 1 are given in Table I.
Run 2
Peroxymonophosphoric acid was prepared and analyzed as in Example 1, but using the following initial mixture:
______________________________________2.00 g potassium peroxydiphosphate; 6.0 g 70% nitric acid;20.3 g distilled reverse-osmosis water.______________________________________
This produced a solution containing 1.9% peroxymonophosphoric acid. The solution and aspen wood meal were mixed, reacted, filtered, extracted, washed, dried and analyzed as in Run 1.
Run 3
Peroxymonophosphoric acid was prepared and analyzed as in Example 1, but using the following initial mixture:
______________________________________2.00 g potassium peroxydiphosphate; 3.0 g 70% nitric acid;10.3 g distilled reverse-osmosis water.______________________________________
This produced a solution containing 3.8% peroxymonophosphoric acid. The delignification of the aspen wood meal was then carried out as in Run 1, except that only 10.4 g of the solution was added to 1.06 g of the milled wood.
Run 4
Peroxymonophosphoric acid was prepared and analyzed as in Run 1, but using the following initial mixture:
______________________________________3.90 g potassium peroxydiphosphate; 6.0 g 70% nitric acid;20.2 g distilled reverse-osmosis water.______________________________________
This produced a solution containing 3.8% peroxymonophosphoric acid. The delignification was then carried out as in Run 1, except that the reaction time was 6.0 hours.
Run 5
Peroxymonophosphoric acid was prepared and analyzed as in Example. 1, but using the following initial mixture:
______________________________________3.90 g potassium peroxydiphosphate; 6.8 g 97% sulfuric acid;19.3 g distilled reverse-osmosis water.______________________________________
This produced a solution containing 3.2% peroxymonophosphoric acid. The delignification was then carried out as in Run 1, except that the reaction time was 22 hours.
Run 6
Peroxymonophosphoric acid was prepared and analyzed as in Run 5. The delignification was carried out as in Run 1, except that the reaction time was 48 hours.
Run 7
Peroxymonophosphoric acid was prepared and analyzed as in Run 1, but using the following initial mixture:
______________________________________7.82 g potassium peroxydiphosphate;12.0 g 70% nitric acid;40.2 g distilled reverse-osmosis water.______________________________________
This produced a solution containing 3.8% peroxymonophosphoric acid the delignification was carried out as in Run 1, except that 50.0 g of cooled solution was added to 1.06 g of aspen meal, and the reaction time was 4 hours.
Run 8
Peroxymonophosphoric acid was prepared and analyzed as in Run 1, but using the following initial mixture:
______________________________________3.90 g potassium peroxydiphosphate; 6.0 g 70% nitric acid;18.1 g distilled reverse-osmosis water.______________________________________
After cooling, 1.7 g of sodium hydroxide was added to the reacted mixture to produce a pH of 2.2 and the solution was then analyzed. It contained 3.8% peroxymonophosphoric acid. This solution was used to delignify milled aspen wood as in Run 1, except that a reaction time of 600 hours was employed.
Run 9
Peroxymonophosphoric acid was prepared as in Run 8, except that after cooling, 2.0 g of sodium hydroxide was added to the reacted mixture to give a pH of 4.3. The solution contained 3.8% peroxymonophosphoric acid and was used to delignify milled aspen wood as in Run 1, except that the reaction time was 169 hours.
Example 2
Delignification of Aspen Wood with Acid Pretreatment
Run 10
Since it was expected that an acid pre-treatment prior to peroxymonophosphate delignification would decrease the degradation of the wood carbohydrates, such a pre-treatment was employed in Runs 10 through 14. This pre-treatment was performed as follows: 15 g of a pH 0.9 sulfuric acid solution (made by adding 0.67 g of 97% sulfuric acid to 99 g distilled reverse-osmosis water) was added to 1.06 g of air-dried milled aspen wood. The mixture was held for 30 minutes at room temperature and then filtered using a sintered glass crucible. The residue was then washed several times with distilled reverse-osmosis water and air-dried for three days. The air-dried residue was then delignified employing exactly the same techniques and conditions as in Run 3 of Example 1. Results for this Run and all other runs of this Example are given in Table I.
Run 11
Acid pre-treatment was performed exactly as in Run 10. The air-dried residue was then delignified applying exactly the same conditions as in Run 4.
Run 12
Acid pre-treatment and delignification were performed exactly as in Run 11, except that the reaction time employed was hours.
Run 13
Acid pre-treatment was performed exactly as in Run 10. The air-dried residue was then delignified applying exactly the same conditions as in Run 7.
Run 14
Acid pre-treatment was performed exactly as in Run 10. Peroxymonophosphoric acid was prepared as in Run 1, but using the 10 following initial mixture:
______________________________________3.90 g potassium peroxydiphosphate; 6.0 g 70% nitric acid;19.8 g distilled reverse-osmosis water.______________________________________
After cooling, 1.2 g of sodium hydroxide was added to the reacted mixture to produce a pH of 0.9, and the solution was then analyzed and found to contain. 3.6% peroxymonophosphoric acid. A 25.3 g portion of this solution was added to the 1.07 g of acid-pre-treated, air-dried aspen wood, and the mixture held at room temperature (22° C.) for 40 hours. Extraction, washing, drying and analytical procedures were performed as in Run 1.
Example 3
Delignification of Aspen Wood at Elevated pH without Pre-treatment.
Run 15
No acid pre-treatment was employed in Runs 15 through 23. Peroxymonophosphoric acid was prepared as in Run 1 of Example 1, but using the following initial mixture:
______________________________________3.91 g potassium peroxydiphosphate; 6.0 g 70% nitric acid;18.8 g distilled reverse-osmosis water.______________________________________
After cooling, 1.8 g of sodium hydroxide was added to the reaction mixture to produce a pH of 2.2, and the solution was then analyzed. It contained 3.7% peroxymonophosphoric acid. This solution was used to delignify milled aspen wood as in Run 1, except that a reaction temperature of 50° C. and a reaction time of 5 hours were employed. Results for this Run and all other runs of Example 3 are given in Table 1.
Run 16
No acid pre-treatment was used. Peroxymonophosphoric acid was prepared as in Run 15, except that 1.9 g of sodium hydroxide was added to the cooled reaction mixture to produce a pH of 4.2. This solution was used to delignify milled aspen wood as in Run 15, except that a reaction time of 25 hours was used.
Run 17
No acid pre-treatment was used. Peroxymonophosphoric acid was prepared as in Run 1, but using the following initial 15 mixture:
______________________________________3.92 g potassium peroxydiphosphate; 6.0 g 70% nitric acid;20.4 g distilled reverse osmosis water.______________________________________
This produced a solution containing 3.8% peroxymonophosphoric acid. This solution was used to delignify milled aspen wood as in Run 1, except that a reaction temperature of 60° C. and a reaction time of 1 hour were employed.
Run 18
No acid pre-treatment was used. Peroxymonophosphoric acid was prepared as in Run 17, except that, after cooling, 1.2 g of sodium hydroxide was added to the reaction mixture to give a pH of 1.0. The solution contained 3.7% peroxymonophosphoric acid and was used to delignify milled aspen wood as in Run 1, except that the reaction temperature was 60° C. and the reaction time was 4 hours.
Run 19
No acid pre-treatment was used. Peroxymonophosphoric acid was prepared as in Run 17, except that, after cooling, 1.5 g of sodium hydroxide was added to the reaction mixture to give a pH of 1.5. The reaction conditions employed were the same as those of Run 18.
Run 20
No acid pre-treatment was used. Peroxymonophosphoric acid was prepared as in Run 17, except that, after cooling, 1.7 g of sodium hydroxide was added to the reaction mixture to give a pH of 2.5. The reaction conditions employed were the same as those of Run 18.
Run 21
No acid pre-treatment was used. Peroxymonophosphoric acid was prepared as in Run 17, except that, after cooling, 2.0 g of sodium hydroxide was added to the reaction mixture to give a pH of 4.3. The reaction conditions employed were the same as those of Run 18, except that a reaction time of 25 hours was used.
Run 22
No acid pre-treatment was used. Peroxymonophosphoric acid was prepared as in Run 17, except that, after cooling, 1.8 g of sodium hydroxide was added to the reaction mixture to give a pH of 2.8. The reaction conditions employed were the same as those of Run 20, except that a reaction temperature of 80° C. was used.
Run 23
No acid pre-treatment was used. Peroxymonophosphoric acid was prepared as in Run 17, except that, after cooling, 2.0 g of sodium hydroxide was added to the reaction mixture to give a pH of 4.1. The reaction conditions employed were the same as those of Run 22, except that a reaction temperature of 5 hours was employed.
Example 4
Delignification of Spruce Wood without Pretreatment.
Run 1
No acid pre-treatment was used. Peroxymonophosphoric acid was prepared and analyzed as in Run 1 of Example 1, but using the following initial mixture:
______________________________________3.95 g potassium peroxydisphosphate; 6.1 g 70% nitric acid;21.0 g distilled reverse-osmosis water.______________________________________
A solution containing 3.7% peroxymonophosphoric acid was produced. Spruce wood meal, 1.07 g air dried (6.9% moisture) which passed through a 40-mesh screen, was mixed with 25.0 g of the above solution and held at room temperature (22° C.) for 16 hours. The reaction mixture was then processed as in Run 1 of Example 1. The results of this delignification run, and Run 2 of Example 4, are given in Table II.
Run 2
No acid pre-treatment was used. Peroxymonophosphoric acid was prepared and analyzed as in Run 1 of Example 1, but using the following initial mixture:
______________________________________5.02 g potassium peroxydisphosphate; 6.0 g 70% nitric acid;19.1 g distilled reverse-osmosis water.______________________________________
This produced a solution containing 5.0% peroxymonophosphoric acid. The solution and spruce wood meal were processed as in Run 1 of this Example, except that a reaction time of 40 hours was used.
Example 5
Delignification of Pine Kraft Pulp
Run 1
Peroxymonophosphoric acid was prepared and analyzed as in Run 1 of Example 1, but using the following initial mixture:
______________________________________1.91 g potassium peroxydiphosphate 8.9 g 70% nitric acid;29.3 g distilled reverse-osmosis water.______________________________________
This produced a solution containing 1.3% peroxymonophosphoric acid. Mixed northern pine kraft pulp, 3.38 g, with 69.3% moisture, was mixed with 22.7 g of the above solution and held at room temperature (22° C.) for 6 hours. The mixture was then processed as in Run 1 of Example 1. No acid pre-treatment was used. Results of this Run and all other runs of Example 5, are given in Table III.
Run 2
Mixed northern pine kraft pulp was delignified using exactly the same conditions as in Run 1 of this Example, except that the reaction time was 16 hours.
Run 3
Mixed northern pine kraft pulp was delignified using exactly the same conditions as in Run 1 of this Example, except that the reaction time was 72 hours.
Run 4
Peroxymonophosphoric acid was prepared and analyzed as in Run 1 of Example 1, but using the following initial mixture:
______________________________________3.91 g potassium peroxydiphosphate 6.0 g 70% nitric acid;20.2 g distilled reverse-osmosis water.______________________________________
This produced a solution containing 3.8% peroxymonophosphoric acid. The solution and pine kraft pulp were processed as in Run 1 of this Example, except that a reaction time of 2 hours was used.
Run 5
An acid pre-treatment was used. This pre-treatment was performed as follows: 14 g of a pH 0.8 sulfuric acid solution (made by adding 0.77 g of 97% sulfuric acid to 99 g distilled reverse osmosis water) was added to 3.31 g of mixed northern pine kraft pulp (69.3% moisture). The mixture was held for 30 minutes at room temperature (22° C.) and then filtered using a sintered glass crucible. The pulp was then washed several times with distilled reverse osmosis water and then de-watered in the crucible to 70% moisture. The de-watered pulp was then delignified using exactly the same conditions as in Run 2 of this Example.
Run 6
Acid pre-treatment was performed exactly as in Run 5 of this Example. Peroxymonophosphoric acid was prepared and analyzed as in Run 1 of Example 1, but using the following initial mixture:
______________________________________1.97 g potassium peroxydiphosphate; 3.0 g 70% nitric acid;10.1 g distilled reverse-osmosis water.______________________________________
This produced a solution containing 3.8% peroxymonophosphoric acid. The delignification was carried out as in Run 5, except that only 10.2 g of the solution was added to the acid-pretreated pine pulp.
Run 7
Acid pre-treatment was performed exactly as in Run 5 of this Example. Peroxymonophosphoric acid was prepared and analyzed as in Run 1 of Example 1, but using the following initial mixture:
______________________________________3.90 g potassium peroxydiphosphate; 3.1 g 70% nitric acid;10.0 g distilled reverse-osmosis water;______________________________________
This produced a solution containing 4.8% peroxymonophosphoric acid. The delignification was carried out as in Run 6 of this Example; however, the increased proportion of the potassium salt raised the pH of the solution to a value of 0.6.
Run 8
Acid pre-treatment was performed exactly as in Run 5 of this Example. Peroxymonophosphoric acid was prepared and analyzed as in Run 1 of Example 1, but using the following initial mixture:
______________________________________3.91 g potassium peroxydiphosphate; 5.0 g 70% nitric acid;10.0 g distilled reverse-osmosis water.______________________________________
This produced a solution containing 5.8% peroxymonophosphoric acid. The increased acid resulted in a pH of -0.3. The delignification was carried out as in Run 6 of this Example.
Run 9
Acid pre-treatment was performed exactly as in Run 5 of this Example. Peroxymonophosphoric acid was prepared and analyzed as in Run 1 of Example 1, but using the following initial mixture:
______________________________________3.91 g potassium peroxydiphosphate; 6.0 g 70% nitric acid;20.2 g distilled reverse-osmosis water.______________________________________
This produced a solution containing 3.7% peroxymonophosphoric acid. The delignification was carried out as in Run 5 of this Example, except that a reaction time of 2 hours was employed.
Run 10
Acid pre-treatment was performed exactly as in Run 5 of this Example. The pre-treated pulp was then delignified using exactly the same conditions as in Run 9 of this Example, except that the reaction time was 4 hours.
Run 11
Acid pre-treatment was performed exactly as in Run 5 of this Example. The pre-treated pulp was then delignified using exactly the same conditions as in Run 9 of this Example, except that the reaction time was 16 hours.
Example 6
Delignification of Aspen Chips with Alkaline Pretreatment.
Run 1
To delignify aspen chips with peroxymonophosphoric acid, it was necessary to increase the permeability of the wood using an alkaline pre-treatment. This pre-treatment was performed as follows: 30.0 g of a 5.0% sodium hydroxide solution was added to 3.12 g of 13-mm aspen chips having a moisture content of 43.7%. The mixture was then subjected to a 700-mm vacuum, and held under the vacuum for 24 hours. The solution was then drained from the chips and the chips washed with distilled reverse-osmosis water until the water was pH neutral. No acid pre-treatment was performed.
Peroxymonophosphoric acid was prepared as in Run 1 of Example 1, but using the following initial mixture:
______________________________________6.7 g potassium peroxydiphosphate;8.0 g 70% nitric acid;25.3 g distilled reverse-osmosis water.______________________________________
This produced a solution containing 4.9% peroxymonophosphoric acid. The well-drained, alkali pre-treated chips were mixed with 28.4 g of the solution and held for 48 hours at room temperature (23° C.). They were then washed with distilled reverse-osmosis water and extracted, as in Run 1 of Example 1, with 1% sodium hydroxide solution at 50° C. The chips fiberized upon extraction. After extraction, the pulp was thoroughly washed and then dried in a vacuum oven at 60° C. for 16 hours and subsequently weighed and analyzed. Results for Runs 1 and 2 of this Example are given in Table IV.
Run 2
To determine pulp strength and brightness, a larger sample of aspen chips (89.1 g) was subjected to the identical techniques and conditions employed in Run 1 of this Example. A strong, bright pulp, which contained only 1.7% lignin, was obtained.
The above examples show that delignification of lignocellulosics is achievable over a broad range of lignocellulosics and a broad range of delignification conditions. An alkaline extraction after the peroxymonophosphoric acid treatment greatly enhances the removal of the fragmented lignin from the lignocellulosic material. The high residue yields and high viscosities at low lignin contents illustrate the high selectivity of this method of delignification. The following data from Run 2 of Example 6 illustrate that strong, bright pulps having high yields can be obtained using the methods of the present invention.
______________________________________Pulp Properties at 290 ml. CSF______________________________________Tensile Index Nm/g 104Burst Index kPam.sup.2 /g 6.5Tear Index mNm.sup.2 /g 5.5ISO Brightness, % 66______________________________________
Example 7
Comparison with Other Inorganic Peracids
Peroxymonophosphoric acid was prepared and analyzed as in Run 4 of Example 1. The delignification was carried out as in Run 4 of Example 1. Results are given in Table V. The results are compared with results from delignification of aspen wood with peroxymonosulfuric acid and with pernitric acid. The peroxymonosulfuric acid was prepared by dissolving Oxone (2KHSO 5 .KHSO 4 . K 2 SO 4 ) in water and adding nitric acid. The pernitric acid was prepared by adding cooled 70% hydrogen peroxide to 90% nitric acid cooled in an ice bath. The solutions were analyzed as in Run 1 of Example 1.
Table V shows that peroxymonophosphoric acid is, by far, the most efficient and selective delignifying agent of the three inorganic peroxides considered. The residue viscosity is much higher at a lower lignin content than for the other two peracids. It has been found that strong pulps can be obtained by delignifying aspen hardboard fiber and sodium hydroxide pretreated aspen chips with peroxymonosulfuric acid (Proceedings, 1994 TAPPI Pulping Conference, Nov. 6-10, San Diego, Calif., Book 2, Pgs. 543-551). Given the high residue viscosity, even stronger pulps can be obtained by delignification with peroxymonophosphoric acid. As shown by Run 2 of Example 6, even without bleaching, a strong, bright pulp is obtained by peroxymonophosphoric acid treatment, followed by alkaline extraction., of alkaline pretreated aspen chips.
TABLE I__________________________________________________________________________Aspen Wood - 19.9% lignin (through 40 mesh)(Examples 1-3) Liquor Lignin 0.5% PMP.sup.1 in to PMP Reaction in Lignin CED Acid Initial Wood Consumed Initial Temperature Reaction Residue Residue Removed Viscosity.sup.3Run Pretreated Solution % Ratio % pH.sup.2 °C. Time Hr. Yield % % % mPa ·__________________________________________________________________________ s 1 No 1.0 25:1 91 -0.1 22 16 70 9.0 68 -- 2 No 1.9 25:1 90 0 22 16 61 2.2 93 23 3 No 3.8 10:1 98 0.3 22 16 62 2.4 92 32 4 No 3.8 25:1 47 0.3 22 6 63 1.4 95 51 5 No 3.2 25:1 86 0 (s).sup.2 22 22 60 0.1 99 40 6 No 3.4 25:1 93 0 (s).sup.2 22 48 59 0.7 98 32 7 No 3.8 50:1 25 0.2 22 4 62 1.6 95 42 8 No 3.8 25:1 59 2.2 22 600 61 2.2 93 10 9 No 3.8 25:1 100 4.3 22 169 79 19.0 25 --10 Yes 3.8 10:1 99 0 22 16 63 1.8 94 3411 Yes 3.8 25:1 46 0.2 22 6 61 1.6 95 6112 Yes 3.7 25:1 69 -0.2 22 16 60 1.3 96 3113 Yes 3.8 50:1 20 0.2 22 3 65 2.9 90 5414 Yes 3.6 25:1 28 0.9 22 40 68 6.8 77 --15 No 3.7 25:1 7 2.2 50 5 85 20.1 14 --16 No 3.7 25:1 100 4.3 50 25 76 18.2 31 --17 No 3.8 25:1 81 0.4 60 1 55 0.5 98 1518 No 3.7 25:1 68 1.0 60 4 59 1.3 96 1219 No 3.7 25:1 38 1.5 60 4 67 9.1 69 --20 No 3.7 25:1 22 2.5 60 4 80 17.3 31 --21 No 3.7 25:1 100 4.3 60 25 76 17.9 32 --22 No 3.1 25:1 93 2.8 80 4 80 24.0 4 --23 No 3.5 25:1 100 4.1 80 5 79 20.3 20 --__________________________________________________________________________ .sup.1 PMP = peroxymonophoshoric acid .sup.2 (s) indicates that sulfuric acid was used in preparing the PMP. .sup.3 TAPPI Method T230 om82
TABLE II__________________________________________________________________________Spruce Wood - 29.1% Lignin (through 40 mesh)(Example 4) PMP Lignin 0.5% Initial Liquor to PMP Reaction Reaction in Lignin CED Acid Solution Wood Consumed Initial Temp. Time Residue Residue Removed Viscosity.sup.1Run Pretreated % Ratio % pH °C. (Hr.) Yield % % % mPa ·__________________________________________________________________________ s1 No 3.7 25:1 70 0.1 22 16 71 8.2 80 222 No 5.0 25:1 78 0.1 22 40 60 0.7 99 15__________________________________________________________________________ .sup.1 TAPPI Mediod T230 om82
TABLE III__________________________________________________________________________Pine Kraft Pulp - 5.1% Lignin - 38 mPa's Initial Viscosity(Example 5) PMP in Liquor Lignin Initial to PMP Reaction in Lignin 0.5% CED Acid Solution Pulp Consumed Initial Temperature Reaction Residue Residue Removed Viscosity.sup.1Run Pretreated % Ratio % PH °C. Time Hr. Yield % % % mPa ·__________________________________________________________________________ s1 No 1.3 25:1 29 -0.2 22 6 97 2.2 59 312 No 1.3 25:1 45 -0.2 22 16 95 1.5 73 273 No 1.2 25:1 83 -0.2 22 72 92 0.6 88 124 No 3.8 25:1 13 -0.1 22 2 96 2.8 47 375 Yes 1.3 25:1 48 -0.2 22 16 93 1.1 80 256 Yes 3.8 10:1 46 -0.2 22 16 94 0.4 92 267 Yes 4.8 10:1 10 0.6 22 16 95 1.9 65 338 Yes 5.8 10:1 47 -0.3 22 16 94 0.4 93 209 Yes 3.7 25:1 14 -0.1 22 2 96 3.4 35 3910 Yes 3.7 25:1 15 -0.2 22 4 95 2.3 57 3611 Yes 3.7 25:1 29 -0.2 22 16 93 0.5 90 26__________________________________________________________________________ .sup.1 TAPPI Method T230 om82
TABLE IV__________________________________________________________________________Aspen Chips - NaOH Pretreated - 19.9% Lignin(Example 6) PMP in Liquor Initial to PMP Reaction Lignin in Lignin 0.5% CED Acid Solution Pulp Consumed Initial Temperature Reaction Residue Residue Removed ViscosityRun Pretreated % Ratio % PH °C. Time Hr. Yield % % % mPa ·__________________________________________________________________________ s1 No 4.9 17:1 86 0.3 23 48 60 1.3 96 402 No 4.9 17:1 90 0.3 23 48 61 1.7 95 36__________________________________________________________________________
TABLE V__________________________________________________________________________Comparison of Peracid Delignification ofAspen Wood (through 40 mesh)(Example 7) Peroxymono- phosphoric Acid Peroxymonosulfuric Acid Pernitric AcidOxidant: H.sub.3 PO.sub.5 H.sub.2 SO.sub.5 HNO.sub.4__________________________________________________________________________REACTIONCONDITIONS:Quantity Applied, 0.13 0.13 0.12g [0]*/g woodQuantity Consumed, 0.063 0.046 0.12g [0]/g woodAcid Concentration, 2.2 2.2 2.2NormalityReaction Time, Hr. 6.0 6.6 6.0Reaction Temperature, 22 22 22°C.RESULTS:Residue Yield, % 63 68 70Lignin in Residue, % 1.4 5.8 9.90.5% CED Viscosity 36 24 9mPa · s__________________________________________________________________________ *[0] indicates active oxygen (one oxygen atom in each peracid molecule is active)
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Disclosed is a method for the delignification of lignocellulosic materials with acidic solutions of peroxymonophosphoric acid for the delignification and brightening of cellulosic pulps in bleaching; for the production of cellulosic pulps for use in paper making and in regenerated cellulose products; for enhancing the properties of recycled cellulosic fibers and for use in animal feeds and other products where removal or degradation of lignin is beneficial.
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BACKGROUND OF THE INVENTION
[0001] This invention relates to mining and metallurgical refining and more particularly to systems and processes for solvent extraction and electroextraction of metals.
[0002] To this end, there are generally two main processes available for precious metal concentration and recovery: zinc precipitation, and electrowinning. Zinc precipitation involves crushing and grinding ore containing the precious metal (e.g., gold), and then combining the ground ore with a water and caustic cyanide solution. The resulting mud-like pulp is moved to a settling tank where the coarser gold-laden solids move to the bottom via gravity, and a lighter first pregnant solution of water, gold, and cyanide moves to the top and is removed for further processing. The gold-laden solids are agitated and aerated in a separate agitated leach process where oxygen reacts to leach the gold into the caustic water and cyanide forming a second pregnant solution. The second pregnant solution passes through a drum filter which further separates remaining solids. The first and second pregnant solutions are combined with zinc to precipitate out the dissolved gold. The resulting precipitated gold concentrate may then be smelted to produce refined gold bar.
[0003] Electrowinning typically involves extracting a precious metal such as gold from an electrolyte. First, activated carbon is combined with a pregnant solution in a batch process step. The activated carbon adsorbs the precious metal contained within the pregnant solution, and becomes “loaded” with the precious metal. The loaded carbon is then descaled by sequentially washing it in three batch process steps to remove ore residue. First, the loaded carbon is moved to a washing tank and then the tank is filled with a dilute acid solution. The washing tank is then drained and the used dilute acid solution is pumped away and disposed of. The same washing tank is then filled with water to rinse remaining acid from the loaded carbon. The water becomes slightly acidic during this process. In a similar fashion to the dilute acid, the used slightly acidic rinse water is also drained from the washing tank, pumped away, and disposed of. Lastly, the tank is filled with a caustic solution, and the activated carbon is washed in the caustic solution. The used caustic solution is then drained from the tank, pumped away, and disposed of. An optional final water rinse step may be performed by again, filling the washing tank with rinse water or pH-neutral solution, rinsing caustic residue from the loaded carbon, and then draining the tank of the used rinse water/solution so that it may be pumped away for disposal.
[0004] After washing, the loaded carbon is removed from the washing tank and then added to a strip solution comprising water, a caustic substance, and cyanide to form a strip solution/loaded carbon slurry. The strip solution/loaded carbon slurry goes through an elution process where high temperatures and pressures are used to “re-leach” gold from the loaded carbon into the caustic strip solution to form an electrolyte solution. The electrolyte solution is then moved to a batch electrolytic cell where wire (e.g., reticulated) or plate cathodes collect deposited gold concentrate during electrolysis. After the batch electrowinning process, the cathodes are manually removed from the cell for cleaning, so that gold concentrate deposited thereon can be removed from the cathodes and readied for smelting. After cleaning, the cathodes are then manually replaced within the electrolytic cell, and the entire sequence of batch washing, elution, and electrowinning processes is repeated. Some cathodes (e.g., wire cathodes, due to their small interstices) are not re-useable and must be recycled after processing, thereby increasing overhead/operational costs.
[0005] FIG. 27 schematically illustrates a conventional metal recovery process 9000 as described above. Activated or reactivated carbon 9560 is suspended within a pregnant solution in a conventional batch carbon loading step 9700 . The pregnant solution is generally formed by percolating a dilute cyanide solution through a heap leach pad of crushed mineral-laden ore (e.g., by way of a drip or spray irrigation having a concentration of about 0.5 to 1 pound of sodium cyanide, potassium cyanide, or calcium cyanide per ton of solution). Once the active carbon adsorbs the desired material (e.g., gold, silver, platinum, lead, copper, aluminum, platinum, uranium, cobalt, manganese) from the pregnant solution, it becomes “loaded” carbon 9570 and enters a batch acid wash process 9100 configured for descaling the loaded carbon 9570 as previously discussed.
[0006] FIG. 28 shows one example of a conventional batch acid washing system 9100 ′. Loaded carbon 9570 enters an acid wash vessel 9120 which receives dilute acid from a dilute acid tank 9140 via a pump 9132 . Dilute acid overflow is captured by a sump pump 9150 which moves the overflow to a neutralizing tank 9160 . Contents of the neutralizing tank 9160 may be moved to a secondary holding tank via a pump 9136 . The conventional batch acid wash process 9100 continues by draining the acid wash vessel 9120 of dilute acid solution, and then filling the vessel 9120 with an aqueous rinse solution. Overflow of aqueous rinse solution is captured by sump pump 9150 which moves the overflow to a neutralizing tank 9160 and/or a holding tank. The process 9100 may continue by draining the vessel 9120 of aqueous rinse solution, and then filling the vessel 9120 with a caustic rinsing agent. Overflow of the caustic rinse may likewise be captured by sump pump 9150 and moved to a neutralizing tank 9160 and/or a holding tank (not shown).
[0007] After the loaded carbon 9570 is descaled, it leaves the batch acid washing process 9100 (via carbon transfer pump 9134 ) and enters a conventional batch (e.g. Zadra strip) elution process 9200 . As shown in FIG. 29 , a conventional batch elution process 9200 typically involves feeding descaled loaded carbon 9500 and/or loaded carbon directly from an adsorption system 9700 into a strip vessel 9240 . Strip vessel 9240 is generally a large cylindrical tank of material suitable for holding reagents at an elevated pressure and temperature (e.g., 138 degrees C.-148 degrees C.). The descaled loaded carbon 9500 is maintained within the strip vessel 9240 at high temperatures and pressure in the presence of a caustic aqueous strip solution comprising cyanide. After a period of time, spent carbon 9550 is removed from the strip vessel 9240 (e.g., via carbon transfer pump 9232 ), and is moved to a carbon handling system or carbon regeneration system 9300 ′ or process 9300 . Hot electrolyte solution 9421 is formed within the strip vessel 9240 as material previously adsorbed onto the loaded carbon leaches into the strip solution. The hot electrolyte solution 9421 is also removed from the strip vessel 9240 and passes through a heating skid 9250 or equivalent heat exchanger for cooling before entering a conventional batch electrowinning system 9400 ′ or process 9400 . Cooling of hot electrolyte solution 9421 to form a lower temperature electrolyte solution 9530 is generally necessary to reduce the risk of flashing within a conventional batch electrolytic metal recovery cell 9420 . The heating skid 9250 also serves to recycle energy by warming cooler barren solution 9540 which exits the electrolytic metal recovery cell 9420 (e.g., at about 66 degrees C.) and/or barren solution 9237 which exits the barren solution storing tank 9220 before re-entering the strip vessel 9240 to serve once again as a strip solution re-leaching agent. Warming of the cooler barren solution 9237 , 9540 to form a hot barren solution 9239 may also be done using a heater in addition to, or in lieu of said heating skid 9250 . One or more pumps 9234 , 9236 are generally used to transfer barren solution back to the strip vessel 9240 . Additional reagent from a reagent handling system and/or more pregnant solution may be added to barren solution tank 9220 as needed.
[0008] As shown in FIG. 30 , electrolyte solution 9530 enters a conventional batch electrolytic metal recovery cell 9420 which operates in batch cycles. A series of parallel plate cathodes are placed within close proximity and the electrolyte solution 9530 is pumped in and agitated around the cathodes. Body portions of the cell 9420 carry an opposing charge with respect to the cathodes, and by virtue of electrolysis, ions contained in the electrolyte solution 9530 are subsequently deposited on the cathodes as a cathode sludge concentrate of the recovery metal or as a solid cathode plating. In operation, cathodes are typically removed simultaneously from the cell 9420 in a batch process step in order to collect the recovered metal. In instances where plate cathodes are used, the cathode may be flexed to delaminate and remove the hard cathode plating from the cathode. In other instances where higher deposition wire mesh (i.e., “reticulated”) cathodes are employed, the concentrate is separated from the cathode in a subsequent process and the cathodes are then recycled. Sludge concentrate may collect at the bottom of the cell 9420 and may be removed periodically. An electrowinning pump box 9440 and pump 9430 may be employed to temporarily store spent electrolyte (i.e., barren solution) which is removed from the cell 9420 between batches.
[0009] Problems associated with the abovementioned conventional acid wash systems 9100 ′ and processes 9100 are numerous. For instance, the systems utilize independent, non-continuous, “batch” process steps which require constant manpower, downtime, and energy (e.g, continually draining and refilling the same acid wash vessel 9120 with different rinsing agents). Moreover, such conventional batch acid wash processes 9100 typically discard expensive acid, caustic, and/or other reagents after each use. This increases overhead (e.g., purchasing costs, disposal costs) and creates unnecessary harm to the environment. Furthermore, every time a conventional acid wash vessel 9120 is drained and re-filled with a different rinsing solution, carbon (and precious minerals/metals attached thereto) may not be recovered due to system inefficiencies caused by heat, friction, increased pump residence time and exposure, an increased number of pipe elbows and valves, and the frequent discarding of spent rinsing solution which may still contain small amounts of loaded carbon and precious metal. In other instances (not shown), if separate vessels are used for each rinse step of the acid wash process, as many as four tanks and ten pumps may be required. This increases both initial plant overhead costs and overall plant footprint.
[0010] Problems associated with the described conventional batch elution process 9200 are also numerous. For instance, the process 9200 employs batch process steps which require constant manpower and energy (e.g., continually draining and refilling the strip vessel 9240 with new strip solution, hot barren solution 9239 , and loaded carbon 9500 each time more electrolyte solution 9530 is needed for electrowinning 9400 ). This increases overhead costs (e.g., labor, maintenance), complicates production scheduling, and may cause harm to the environment. Furthermore, conventional metal recovery systems 9000 ′ are bulky and require large plant layout footprints as demonstrated by FIG. 23 , when compared to a system 100 ′ for the continuous recovery of metals according to the invention ( FIG. 22 ) which will be described hereinafter. Moreover, conventional elution systems have limited operating flow rates, temperatures, and pressures which drive up radiation losses and power consumption. Additionally, the electroextraction of metals using the conventional “batch” electrowinning processes 9400 described above requires intervals of non-production downtime of the electrowinning cell 9420 and significant physical labor, which may contribute to premature cathode wear and wasted electrolyte solution 9530 .
[0011] The process of using zinc to precipitate precious metals out of pregnant solutions is also costly, may be less efficient for large-scale operations, works for only certain metals, and may result in less precious metal recovery.
OBJECTS OF THE INVENTION
[0012] It is, therefore, an object of the invention to provide an improved metal recovery system which is configured for continuous carbon loading/adsorption, continuous washing and stripping of loaded carbon, continuous electrolyte formation, continuous electrowinning, and continuous regeneration/re-activation, thereby avoiding the aforementioned problems associated with conventional batch metal recovery processes.
[0013] Another object of the invention is to improve the efficiency of a metal recovery process (e.g., by minimizing radiation losses, reducing power consumption, minimizing reagent consumption, and preventing carbon breakdown and electrolyte loss).
[0014] Yet another object of the invention is to prevent or minimize carbon loss and reagent waste.
[0015] Another object of the invention is to maximize total metal recovery.
[0016] Another object of the invention is to provide a metal recovery system which is configured to cost less and have a smaller footprint area than conventional metal recovery systems.
[0017] Another object of the invention is to provide a system and process for the recovery of metals which is configured to operate at higher flow rates, temperatures, and/or pressures than conventional processes.
[0018] Yet even another object of the invention is to reduce the percentage by weight of unrecovered metal present in spent electrolyte/barren solution.
[0019] These and other objects of the invention will be apparent from the drawings and description herein. Although every object of the invention is believed to be attained by at least one embodiment of the invention, there is not necessarily any one embodiment of the invention that achieves all of the objects of the invention.
SUMMARY OF THE INVENTION
[0020] A system for the continuous recovery of metals is provided. The system comprises, in accordance with some embodiments of the invention, at least one of a continuous acid wash system configured for receiving a continuous, uninterrupted inflow of loaded carbonaceous particulate and delivering a continuous, uninterrupted outflow of descaled loaded carbonaceous particulate; a continuous elution system configured for receiving a continuous, uninterrupted inflow of a strip solution containing a descaled loaded carbonaceous particulate and delivering a continuous, uninterrupted outflow of electrolyte solution; and a continuous electrowinning system configured for receiving a continuous, uninterrupted inflow of electrolyte solution, delivering a continuous uninterrupted outflow of a barren solution, and continuously and uninterruptedly forming a cathode sludge concentrate. Each of the continuous acid wash system, the continuous elution system, and the continuous electrowinning system are generally configured to operate simultaneously without periodic interruptions which are common with conventional batch metal recovery processes.
[0021] In some embodiments, the system may comprise an integrated carbon regeneration system operatively connected to the continuous elution system. A continuous carbon loading/adsorpsion system may be operatively connected to and upstream of the continuous acid wash system. The continuous acid wash system may be operatively connected to the continuous elution system; for example, via a holding tank between said continuous acid wash system and said continuous elution system. One or more pumps may be provided to facilitate the transportation of slurry and solids within the system. In preferred embodiments, the continuous elution system is operatively connected to the continuous electrowinning system and comprises one or more screens or filters configured to prevent carbonaceous particulate from passing to the continuous electrowinning system.
[0022] The continuous acid wash system may comprise a chamber adapted for retaining a fluidization medium; an inlet adapted for receiving a feed containing loaded carbonaceous particulate; a fluidized bed distribution panel or other means adapted for fluidizing the loaded carbonaceous particulate in the presence of said fluidization medium; an opening adapted to pass loaded carbonaceous particulate and fluidization medium from the chamber; and a screen adapted to filter loaded carbonaceous particulate from a fluidization medium. The continuous elution system may comprise a splash vessel, a continuous elution vessel, and a flash vessel, wherein the splash vessel is operatively connected to the continuous elution vessel in series, the continuous elution vessel is operatively connected to the flash vessel in series, and the splash vessel is operatively connected to the flash vessel in parallel. The continuous electrowinning system comprises an electrolytic cell having a cell body configured to maintain electrolyte solution at a high pressure and/or temperature; at least one anode; at least one cathode; an inlet configured for receiving a continuous, uninterrupted influent stream of electrolyte solution; a first outlet configured for discharging a continuous, uninterrupted effluent stream of spent electrolyte solution; a second outlet configured for removing cathode sludge concentrate; and a residence chamber configured to continuously transfer electrolyte solution from said inlet to said first outlet and increase residence time of said electrolyte solution between said at least one anode and said at least one cathode. The residence chamber may comprise one or more channels which are configured to provide a forced flow of electrolyte solution therein which is strong enough to continuously dislodge and/or transport cathode sludge concentrate along said one or more channels and eventually out of said residence chamber.
[0023] The continuous elution vessel may comprise an influent manifold and an effluent manifold which communicate with the first outlet and inlet of the electrolytic cell, respectively, and may further comprise a fluidized bed and/or one or more internal baffles which are configured to torture flow paths and increase a residence time of loaded carbonaceous particulate therein. A valve configured to flash solution leaving the continuous elution vessel and entering the flash vessel may also be provided.
[0024] The continuous acid wash system may comprise at least one of an acid solution, an aqueous solution, and a caustic solution. The continuous elution system may comprise a solution containing at least one of a carbonaceous particulate loaded with a precious metal, an electrolyte solution, spent carbonaceous particulate, a caustic, an aqueous component, and cyanide. The continuous electrowinning system may comprise an electrolyte solution or cathode sludge concentrate. Each of the continuous acid wash system, the continuous elution system, and the continuous electrowinning system may be configured to increase a residence time, pressure, or temperature of solutions or slurries contained therein and may comprise a screen or filter element.
[0025] In some embodiments, the continuous acid wash system may comprise multiple washing vessels, each washing vessel comprising a chamber adapted for retaining a fluidization medium; an inlet adapted for receiving a feed containing a loaded carbonaceous particulate; a fluidized bed distribution panel or other means adapted for fluidizing and cleaning the loaded carbonaceous particulate with said fluidization medium; an opening adapted to pass loaded carbonaceous particulate and fluidization medium from the chamber; and a screen adapted to filter loaded carbonaceous particulate from fluidization medium. For instance, in some embodiments, the continuous acid wash system may comprise an acid wash tank containing an acidic fluidization medium, an aqueous rinse tank containing a substantially pH-neutral aqueous solution, and a caustic rinse tank containing an alkaline fluidization medium.
[0026] In some embodiments, the continuous acid wash system may comprise one or more recirculation tanks for collecting spent fluidization medium, and one or more weirs, channels, valves, or drains for capturing spent fluidization medium. The continuous electrowinning system may be configured for continuous and uninterrupted collection and removal of said cathode sludge concentrate and may comprise one or more channels defined between a cathode, an anode, and an insulator. The one or more channels may comprise portions of a helix, spiral, coil, compound curve, 3D-spline curve, figure-8, or serpentine shape and the cathode and anode may be formed as sleeves or tubes which are separated by said insulator. In some embodiments, the carbon regeneration system is operatively connected to both the continuous elution system and the continuous carbon loading/adsorpsion system, and the continuous carbon loading/adsorpsion system is operatively connected to said continuous acid wash system.
[0027] A process for the continuous recovery of a metal is also disclosed. The process, comprises, in accordance with some embodiments, continuously feeding a continuous wash system with particulate loaded with a metal; continuously washing said loaded particulate within the continuous wash system to descale the loaded particulate; continuously removing descaled loaded particulate from said continuous wash system; continuously loading a continuous elution system with said descaled loaded particulate; continuously removing electrolyte solution from said continuous elution system; continuously feeding a continuous electrowinning system with said electrolyte solution; continuously removing spent electrolyte solution from said continuous electrowinning system; and, continuously delivering said spent electrolyte solution to said continuous elution system; wherein each of the continuous wash system, the continuous elution system, and the continuous electrowinning system are configured to allow the above steps to be performed simultaneously, without the periodic interruptions required for conventional batch processes.
[0028] The process may further comprise continuously removing spent particulate from the continuous elution system; continuously feeding said spent particulate to a carbon regeneration system; continuously removing cathode sludge concentrate from the continuous electrowinning system; and/or forming said loaded particulate by continuously adsorbing metal onto said particulate in a continuous carbon loading/adsorption system which is similar to or identical to said continuous wash system. The particulate may be one of a carbonaceous particulate, a polymeric adsorbent, or an ion-exchange resin.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIGS. 1 and 2 schematically illustrate a system and method for the continuous recovery of metals according to some embodiments;
[0030] FIG. 3 is a flowchart of a three-sequence continuous acid wash operation according to some embodiments;
[0031] FIGS. 4 and 5 outline steps of a continuous acid washing process according to some embodiments;
[0032] FIGS. 6 and 7 depict a washing tank which may be used in the acid wash process shown in FIGS. 1-5 ;
[0033] FIG. 8 shows an acid wash system comprising a plurality of the washing tanks depicted in FIGS. 6 and 7 ;
[0034] FIGS. 9 and 12 schematically illustrate a system and method of continuous elution according to some embodiments;
[0035] FIG. 10 is an isometric view of a continuous elution system according to some embodiments;
[0036] FIG. 11 shows a side cutaway view of the continuous elution system of FIG. 10 ; FIGS. 13 and 19 schematically illustrate a system and method of continuous electrowinning according to some embodiments;
[0037] FIG. 14 shows a top plan view of a continuous electrowinning system according to some embodiments;
[0038] FIGS. 15 and 16 are vertical and isometric cutaway views, respectively, of a continuous electrowinning system taken on line XV-XV in FIG. 14 ;
[0039] FIG. 17 is a detailed view of FIG. 15 , showing the particulars of an inlet according to some embodiments;
[0040] FIG. 18 is a transverse cutaway view of an electrowinning cell along line XVIII-XVIII in FIG. 14 ;
[0041] FIG. 20 shows a process for regenerating/reactivating spent carbon according to some embodiments;
[0042] FIGS. 21 and 22 show a system for the continuous recovery of metals;
[0043] FIG. 23 shows a conventional batch system for the recovery of metals;
[0044] FIG. 24 shows an alternative to the washing tank shown in FIGS. 6-8 or an apparatus to be used for continuous carbon loading/adsorption;
[0045] FIG. 25 shows a detailed isometric view of the chamber shown in FIG. 24 ;
[0046] FIG. 26 is a cutaway view of the chamber shown in FIG. 25 ;
[0047] FIG. 27 shows a conventional system for the recovery of metals.
[0048] FIG. 28 shows a conventional acid wash process;
[0049] FIG. 29 shows a conventional batch elution process; and,
[0050] FIG. 30 shows a conventional batch electrowinning process.
DETAILED DESCRIPTION OF THE INVENTION
[0051] As shown in FIGS. 1 and 2 , a plant system 100 ′ or process 100 for the continuous recovery of a metal from mined ore may comprise, in accordance with some embodiments of the invention, a continuous acid wash system 10 ′ or process 10 , a continuous elution system 20 ′ or process 20 , a continuous electrowinning system 40 ′ or process 40 , a continuous carbon regeneration system 30 ′ or process 30 , and a continuous carbon loading/adsorption system 70 ′ or process 70 . Activated/reactivated carbon 56 (which may be derived for example, from coconut shells or charcoal), or alternatively, an equivalent particulate substance such as loaded polymeric adsorbent or loaded ion-exchange resin, is subjected to a continuous carbon adsorption process 70 where it spends a time of residence suspended in a pregnant solution which contains a dissolved target recovery metal such as gold, silver, copper, aluminum, platinum, uranium, chromium, zinc, cobalt, manganese, or lead. The continuous carbon loading/adsorption system 70 ′ or process 70 may comprise, for example, an apparatus as shown in FIGS. 6 and 7 or FIGS. 24-26 which serves to fluidize the activated/reactivated carbon 56 within the pregnant solution. Once the carbon 56 becomes loaded with the target recovery metal, it undergoes a continuous acid wash process 10 . Descaled loaded carbon 50 leaving the continuous acid wash process 10 enters a holding tank 60 filled with a strip solution containing one or more reagents (e.g., water, caustic, and cyanide) to form a slurry 51 of strip solution and descaled loaded carbon 50 . The slurry 51 enters a continuous elution process 20 where the temperature and/or the pressure of the slurry 51 is increased and the target recovery metal previously adsorbed by the carbon is re-leached into the strip solution thereby forming an electrolyte solution 53 which may be used for a continuous electrowinning process 40 . Barren solution (i.e., spent electrolyte) 54 leaving the continuous electrowinning process 40 is returned to the continuous elution process 20 and/or the holding tank 60 for re-use. A solids fraction 55 of spent carbon, depleted of its target recovery metal via the continuous elution process 20 , moves to a carbon regeneration process 30 for reactivation before being re-used in the continuous carbon loading/adsorption process 70 .
[0052] As shown in FIGS. 2-5 , a continuous acid wash process 10 may generally comprise the steps of: feeding 1004 loaded carbon 57 into a continuous acid wash system 10 ′, fluidizing 1006 incoming loaded carbon 57 in a dilute acid solution within a first acid wash tank 12 , extracting 1008 loaded carbon from the acid wash tank 12 , screening 1010 the extracted loaded carbon to remove the dilute acid solution, capturing 1012 dilute acid solution 57 c separated from the loaded carbon, optionally processing 1014 the captured dilute acid solution 57 c (e.g., filtering, additives, pH adjust), and recycling the dilute acid solution 57 c by feeding 1016 the dilute acid solution 57 c back into the acid wash tank 12 . Acid-rinsed loaded carbon 57 a which has undergone an acid bath in acid wash tank 12 is fed 1018 into a second aqueous rinse tank 14 containing water or another pH-neutral aqueous rinse solution 57 d , and then fluidized 1020 in said aqueous rinse tank 14 . The process 10 further comprises extracting 1022 rinsed loaded carbon 57 b from the aqueous rinse tank 14 , screening 1024 the extracted rinsed loaded carbon 57 b to remove aqueous rinse solution 57 d , capturing 1026 separated aqueous rinse solution 57 d separated from the rinsed loaded carbon 57 b , optionally processing 1028 the captured aqueous rinse solution 57 d (e.g., filtering, additives, pH adjust), and recycling the aqueous rinse solution 57 d by feeding 1030 the aqueous rinse solution 57 d back into the aqueous rinse tank 14 . Rinsed loaded carbon 57 b which has undergone washing in aqueous rinse tank 14 is fed 1032 into a third caustic rinse tank 16 containing a caustic rinse solution 57 e , and is then fluidized 1034 in said caustic rinse tank 16 . The continuous acid wash process 10 further comprises extracting 1036 descaled loaded carbon 50 from the caustic rinse tank 16 , screening 1038 the extracted descaled loaded carbon 50 to remove caustic rinse solution 57 e , capturing 1040 caustic rinse solution 57 e separated from the descaled loaded carbon 50 , optionally processing 1042 the captured caustic rinse solution 57 e (e.g., by filtering, providing additives, or adjusting pH), and recycling the caustic rinse solution 57 e by feeding 1044 the solution 57 e back into the caustic rinse tank 16 . The continuous acid wash process 10 may comprise the step of providing one or more pumps 13 a , 13 b for re-circulating the rinsing solutions in each of the aforementioned tanks 12 , 14 , 16 . Optionally, a fourth aqueous rinse cycle (not shown) may be provided, and one of ordinary skill in the art would acknowledge that any one or more of the aforementioned washing steps may be repeated or alternated.
[0053] Turning now to FIGS. 6 and 7 , an acid wash tank 200 for cleaning and descaling a loaded particulate material may be employed for any portion of the continuous acid wash process 10 . The loaded particulate material washed within said acid wash tank 200 may be of any particle size, shape, and density which can be fluidized by or suspended within a cleaning fluidization medium. The acid wash tank 200 is advantageously configured to descale active carbon particulate which has been loaded with a target metal, in preparation for creating an electrolyte for electrowinning. In such instances, the acid wash tank 200 may be filled with a fluidization medium comprising acid. Similar tanks 200 ′, 200 ″ may be used with fluidization mediums comprising water or caustic soda. Moreover, similar tanks may be used in yet other processes such as a continuous carbon loading/absorption process 70 , wherein the particulate comprises activated/reactivated carbon 56 , and the fluidization medium comprises a pregnant solution formed by percolating cyanide and/or other reagents through a heap leach pad of crushed ore containing a target metal or mineral.
[0054] According to some embodiments, acid wash tank 200 may comprise an acid wash tank having a first chamber 220 , a first fluidized bed distribution panel 221 , a first inlet 222 , a first recirculation inlet 223 a , a first recirculation outlet 223 b , a first weir 224 , a first screen 226 , a first overflow outlet 227 , a first discharge outlet 228 , a first recirculation tank 229 , a bottom wall 260 , an inner tubular wall 266 , an outer tubular wall 268 , and a first channel 282 defined between the inner tubular wall 266 and outer tubular wall 268 adjacent the first weir 224 . The first screen 226 serves to filter an incoming feed by separating its liquid fraction (e.g., spent pregnant solution, fluidization medium, or transport fluid) from its solid particulate fraction (metal-laden loaded or reloaded carbon). The liquid fraction drained from the particulate is maintained in the first recirculation tank 229 and may be removed through first recirculation outlet 223 b . The first recirculation outlet 223 b may be sealed during operation, coupled to a holding tank, coupled to a drain, coupled to a sump pump, or otherwise configured to feed an upstream or downstream process.
[0055] In some embodiments, as shown in FIG. 8 , a continuous acid wash system 10 ′ may comprise one or more separate washing tanks 200 , 200 ′, 200 ″ connected in series in order to provide flexibility in customizing plant layout and/or reduce overall footprint. In some instances, the tanks 200 , 200 ′, 200 ″ may comprise similar or identical design characteristics, each containing different fluidization mediums. For example, in some embodiments, a first tank 200 may comprise an acid wash tank containing a strong or dilute acid solution 57 c , whereas second 200 ′ and third 200 ″ tanks may comprise aqueous and caustic rinsing tanks containing aqueous 57 d and caustic 57 e rinsing agents, respectively. While not required, tanks 200 , 200 ′, and 200 ″ may be constructed as “universal” or “interchangeable” tanks. Moreover, tanks 200 , 200 ′, 200 ″ may be configured with tubular (e.g., cylindrical pipe or prismatic extrusion) shapes as shown in order to reduce manufacturing costs. Any one or more of tanks 200 , 200 ′, and 200 ″ may be replaced with a tank of dissimilar scale or a tank 2000 as shown in FIGS. 24-26 , which will be described hereinafter.
[0056] A first fluidization medium comprising a dilute acid or anti-scaling agent solution may occupy the first acid wash tank 200 . In some embodiments, the first fluidization medium may comprise a solution of 1-10% vol/vol mineral acid, such as nitric acid or hydrochloric acid configured to dissolve carbonate scale. In use, incoming loaded/reloaded carbon 57 moves over the first screen 226 and flows into the first chamber 220 of the first acid wash tank 200 via the first inlet 222 . Fluid which may be present with the incoming loaded/reloaded carbon 57 is drained and enters the first recirculation tank 229 . The screened loaded carbon subsequently falls downwardly along the first screen 226 and towards the first fluidized bed distribution panel 221 and is fluidized by the first fluidization medium. The first fluidization medium enters the first recirculation inlet 223 a and passes through distribution panel 221 . Clarified first fluidization medium rises above the highest suspended level of loaded carbon within the first acid wash tank 200 and pours over the first weir 224 and into the first channel 282 . Thereafter, clarified first fluidization medium exits the first acid wash tank 200 via outlet 227 and optionally feeds the first recirculation inlet 223 a and first fluidized bed distribution panel 221 . One or more pumps 13 a may be provided between outlet 227 and inlet 223 a.
[0057] A slurry of acid-rinsed loaded carbon 57 a and residual first fluidization medium exits the first acid wash tank 200 through the first discharge opening 228 and enters a second aqueous rinse tank 200 ′ through a second inlet 232 . The acid-rinsed loaded carbon 57 a may be conveyed to the tank 200 ′ using only gravitational forces, or the acid-rinsed loaded carbon 57 a may be conveyed to the tank 200 ′ using one or more slurry pumps (not shown). A second fluidization medium such as a substantially pH-neutral aqueous scrubbing solution or a hot water may occupy the second aqueous rinse tank 200 ′. In use, the acid-rinsed loaded carbon 57 a and first fluidization medium moves over a second screen 236 or equivalent filter and then flows into the second chamber 230 for pre-soak. The second screen 236 serves to separate residual first fluidization medium liquid from the acid-rinsed loaded carbon 57 a , wherein drained first fluidization medium is maintained in a second recirculation tank 239 and may be removed through second recirculation outlet. The second recirculation outlet 233 b may be coupled to a holding tank, a filtering apparatus, or an upstream or downstream process. For instance, as schematically indicated by the dotted line path of dilute acid solution 57 c ′, the second recirculation outlet 233 b may be operatively connected to the first recirculation inlet 223 a to fluidize loaded/reloaded carbon 57 within the first washing tank 200 . Though not shown, one or more pumps may be disposed between the outlet 233 b and inlet 223 a.
[0058] After passing over the second screen 236 , acid-rinsed loaded carbon 57 a subsequently falls towards a second fluidized bed distribution panel 231 and is fluidized within the second chamber 230 by a flow of second fluidization medium entering the second recirculation inlet 233 a and passing upwards through panel 231 . Clarified second fluidization medium free of loaded carbon particulate rises above a suspended level of acid-washed loaded carbon and pours over a second weir 234 and into a second channel 284 , where it exits the second aqueous rinse tank 200 ′ via outlet 237 and optionally feeds the second recirculation inlet 233 a and second fluidized bed distribution panel 231 as schematically illustrated by dotted line path taken by aqueous rinse solution 57 d.
[0059] A slurry of rinsed loaded carbon 57 b and second fluidization medium exits the second washing tank 200 ′ through second discharge opening 238 and enters a third washing tank 200 ″ through a third inlet 242 . The rinsed loaded carbon 57 b may be conveyed to the third caustic rinse tank 200 ″ using only gravitational forces, or the rinsed loaded carbon 57 b may be conveyed to the tank 200 ″ using one or more pumps (not shown). A third fluidization medium such as a caustic rinse solution may occupy the third washing tank 200 ″. For example, the third fluidization medium may comprise an amount of sodium hydroxide (NaOH) or potassium hydroxide (KOH) between 0.5% and 5% wt, for instance 1% wt. The third fluidization medium may comprise other reagents, for instance 1-10% wt sodium cyanide (NaCN). The third fluidization medium may be heated (e.g., 20-100 degrees C.). In use, a slurry of rinsed loaded carbon 57 b and second fluidization medium flows over a third screen 246 or equivalent filter and into the third chamber 240 . The third screen 246 serves to filter the slurry by separating its second fluidization medium liquid fraction from its rinsed loaded carbon 57 b solid fraction. The separated second fluidization medium is maintained in a third recirculation tank 249 . The second fluidization medium may be removed from the tank 249 via a third recirculation outlet 243 b which may be coupled to a holding tank, filtering apparatus, or one or more upstream or downstream processes. For instance, as schematically indicated by path taken by aqueous rinse solution 57 d ′, the third recirculation outlet 243 b may be operatively connected to the second recirculation inlet 233 a in order to help fluidize particulate within the second washing tank 200 ′. Though not shown, one or more pumps may be disposed between the outlet 243 b and inlet 233 a . In some instances, outlet 243 b and inlet 233 a may be operatively connected to a plant water system.
[0060] After passing over third screen 246 , twice-rinsed loaded carbon particulate subsequently falls towards a third fluidized bed distribution panel 241 and is fluidized within the third chamber 240 by a flow of third fluidization medium entering the third recirculation inlet 243 a and passing through the panel 241 . Clarified third fluidization medium rises above the highest level of suspension of the loaded carbon fluidized within the tank 200 ″ and pours over a third weir 244 and into a third channel 286 , where it exits the caustic rinse tank 200 ″ via outlet 247 and optionally feeds the third recirculation inlet 243 a as indicated by the dotted line path taken by caustic rinse solution 57 e.
[0061] A slurry of caustic-rinsed, descaled loaded carbon 50 and third fluidization medium exits the third caustic rinse tank 200 ″ through third discharge opening 248 and may be subsequently screened or filtered for further processing. After leaving the tank 200 ″, de-scaled loaded carbon 50 within the slurry may be separated from the third fluidization medium liquid fraction by a screen or filter (not shown) and then added to a strip solution of water, caustic, and cyanide in a holding tank 60 for use in downstream continuous elution 20 and electrowinning 40 processes.
[0062] The continuous acid wash system 10 ′ shown and described, when used, reduces or eliminates the need to continually purchase and replace lost quantities of carbon particulate, water, caustic, acid, and/or other anti-scaling agents. System 10 ′ also significantly reduces the amount of spent solution and carbon requiring disposal and reduces the potential for environmental harm.
[0063] It should be known that the particular features and suggested uses of the continuous acid wash system 10 ′ described herein are exemplary in nature and should not limit the scope of the invention. For example, fluidized bed portions 221 , 231 , 241 may be replaced with, or used in combination with one or more mechanical or forced air agitators (not shown) to suspend loaded carbon particulate in fluidization medium. Moreover, the number of chambers 220 , 230 , 240 per system 10 ′ may be greater or less than what is shown. In some embodiments, the relative sizes, dimensions and/or volumes of chambers 220 , 230 , 240 may vary. In other embodiments, the chambers 220 , 230 , 240 may be dimensioned and proportioned similarly. Additionally, one or more tanks 200 , 200 ′, 200 ″ may be placed in parallel with others in order to increase throughput. For example, a third caustic rinse tank 200 ″ of a system 10 ′ may be directly or indirectly coupled to a plurality of upstream aqueous rinse tanks 200 ′. Multiple tanks 200 may replace any one of the single tanks 200 , 200 ′, 200 ″ in system 10 ′ by splitting inlets 222 , 223 a ; 232 , 233 a ; 242 , 243 a and/or outlets 223 b , 227 ; 233 b , 237 ; 243 b , 247 . Moreover, any one chamber 220 , 230 , 240 may be compartmentalized into multiple chambers. As previously stated, the system 10 ′ or portions thereof may be used to continuously load activated carbon in a continuous carbon loading/adsorption process 70 . For example, infeed particulate may comprise activated or reactivated carbon and the first, second, and third fluidization mediums may comprise a pregnant solution (e.g., sodium cyanide (NaCN) solution containing a dissolved precious metal).
[0064] FIG. 9 illustrates a continuous elution process 20 according to some embodiments. A feed slurry 51 of strip solution and descaled loaded carbon 50 is moved to a splash vessel 22 via gravity or one or more pumps 23 . The splash vessel 22 increases the temperature and/or pressure of incoming slurry 51 and delivers the hot pressurized slurry 51 a to a continuous elution vessel 24 . In the continuous elution vessel 24 , target metal previously adsorbed onto the loaded carbon is leached into the strip solution to form an electrolyte solution 53 . The electrolyte solution 53 is filtered by one or more screens to remove spent carbon and non-stripped loaded carbon from the electrolyte solution 53 , before it is moved to a continuous electrowinning process 40 . Electrolyte solution 53 may be conveyed to the continuous electrowinning process via an effluent manifold 28 b provided on the continuous elution vessel 24 . Spent slurry 51 c of strip solution and spent carbon is flashed by a valve 29 and enters into a flash vessel 25 where steam is captured and returned to the splash vessel 22 via a steam return 21 to help heat and pressurize the splash vessel 22 in an efficient manner. The resulting concentrated spent slurry 51 d is separated into solid 55 and liquid 52 fractions using a dewatering screen 26 . The liquid fraction 52 of concentrated spent slurry 51 d may be returned to holding tank 60 , and the solids fraction 55 of the concentrated spent slurry 51 d (i.e., spent de-watered carbon) may be sent to a carbon regeneration process 30 for reactivation. Barren solution 54 returning from a continuous electrowinning process 40 is generally heated with an immersion heater 27 and then sent back to the continuous elution vessel 24 via one or more pumps 23 and an influent manifold 28 a.
[0065] FIG. 10 shows a continuous elution system 20 ′ according to some embodiments. The continuous elution system 20 ′ generally comprises a first splash vessel 22 , a second continuous elution vessel 24 , and a third flash vessel 25 connected in series via piping sections, and a steam return 21 extending between the splash 22 and flash 25 vessels in parallel. One or more pumps 23 may be provided at various portions of the system 20 ′ in order to facilitate flows to, from, and between the vessels 22 , 24 , 25 , other parts of the system 20 ′, and/or other portions 10 ′, 30 ′, 40 ′ within a system 100 ′ for the continuous recovery of metals.
[0066] As shown in FIG. 11 , the continuous elution vessel 24 comprises a fluidized bed distribution panel 320 which separates a residence chamber 340 from a fluidizing chamber 350 . One or more baffles 318 may be provided within the residence chamber 340 in various configurations (e.g., number, angle, spacing, geometry), in order to increase the residence time of incoming hot pressurized slurry 51 a within the continuous elution vessel 24 . The one or more baffles 318 may be parallel and staggered to create a serpentine flow path 51 b of hot pressurized slurry 51 a . The baffles 318 may be parallel, non-parallel, staggered at a single predetermined angle, or disposed in alternating fashion with each baffle oriented in a different predetermined angle. It should be understood that other baffle patterns and arrangements may be used without limitation, and that the shapes, porosities, and/or textures of baffles 318 may differ from what is shown. For example, any one or more of the baffles 318 may comprise folds, bends, curves, corrugations, openings, lattice structures, or the like.
[0067] Slurry flowing within the continuous elution vessel 24 may contain incoming hot pressurized slurry 51 a and barren solution 54 leaving a continuous electrowinning system 40 ′ or process 40 . Fluidizing chamber 350 may be fed by an influent manifold 28 a connected to the continuous elution vessel 24 via one or more influent ports 326 having influent port mounts 322 . Alternatively, the influent manifold 28 a may instead be connected directly to the one or more sidewalls 310 of the continuous elution vessel 24 . A stream of barren solution 54 flows into the continuous elution vessel 24 via the influent manifold 28 a . The stream enters and fills the fluidizing chamber 350 and flows through fluidized bed 320 to help fluidize and suspend carbon particulate within the residence chamber 340 as it travels along the serpentine flow path 51 b.
[0068] An effluent manifold 28 b is also provided to the continuous elution vessel 24 to extract an electrolyte solution 53 from the residence chamber 340 and deliver said electrolyte solution 53 to a continuous electrowinning system 40 ′ or process 40 . Effluent manifold 28 b comprises one or more effluent manifold ports, which may be provided with effluent manifold port mounts for ease of connection to the continuous elution vessel 24 . Similarly to the influent manifold 28 a , the effluent manifold 28 b may be connected directly to the one or more sidewalls 310 of the continuous elution vessel 24 , or may be connected to the vessel 24 via one or more effluent ports 316 having effluent port mounts 312 .
[0069] While in the residence chamber 340 of the continuous elution vessel 24 , loaded carbon is exposed to strip solution reagents under high temperature and high pressure conditions. The reagents in the strip solution act to strip the loaded carbon of its previously adsorbed metal contents (e.g., gold), and “re-leach” it into the solution to form an electrolyte solution. One or more screens or filters 324 may be provided between the residence chamber 340 and the effluent manifold 28 b in order to extract a clarified stream of electrolyte solution 53 from the continuous elution vessel 24 and/or prevent carbon particulate from passing downstream of the effluent manifold 28 b . In some embodiments, as shown, the placement of said screens or filters 324 may be at the interface between the effluent ports and the one or more sidewalls 310 of the continuous elution vessel 24 . However, the screens or filters 324 may be provided in other locations without limitation, for instance: within the effluent manifold 28 b , within the continuous elution vessel 24 , at the interface between the effluent manifold 28 b and mounts 312 , or downstream of said effluent manifold 28 b . It should be known that one or more seals or gaskets (not shown) may be placed between the influent 28 a or effluent 28 b manifolds and the continuous elution vessel 24 .
[0070] Fluidized carbon and solution within residence chamber 340 continues to move along the serpentine flow path 51 b until it is either removed through effluent manifold 28 b to be used as electrolyte, or passes through outlet 328 . The outlet 328 may comprise an outlet mount 330 and/or an outlet seal 329 for connecting to a valve 29 . The valve 29 may be of any sort known in the art, such as a ball or cone valve without limitation, and one would appreciate that the valve may be separately coupled to, or formed integrally with either one or both of the continuous elution vessel 24 and the flash vessel 25 . Moreover, additional piping sections may be added between the second outlet 328 and the valve 29 if the distance between the continuous elution vessel 24 and the flash vessel 25 is large.
[0071] The stream of hot pressurized spent slurry 51 c exiting the continuous elution vessel 24 “flashes” as it passes through the valve 29 . The resulting mixture of gas vapors, fluids, and solids enters the lower pressure flash vessel 25 , where heated steam is diverted back to the splash vessel 22 via steam return piping 21 . Unvaporized spent solution and spent carbon leave the flash vessel 25 in a stream of concentrated spent slurry 51 d . The concentrated spent slurry 51 d may comprise a barren solution liquid fraction 52 , and a solids fraction 55 of spent carbon substantially-free of previously-adsorbed precious metal (e.g., gold). As previously mentioned, the stream of concentrated spent slurry 51 d may be subsequently screened or filtered by a dewatering screen 26 .
[0072] In the embodiment shown, a liquid fraction 52 of the concentrated spent slurry 51 d is separated from the solid fraction 55 by dewatering screen 26 and returned to the holding tank 60 for re-use as strip solution. One or more pumps (not shown) may be provided to move the liquid fraction 52 to the holding tank 60 . The solids fraction 55 of dewatered spent carbon is sent to a carbon regeneration process 30 comprising a regeneration kiln 35 or other means for reactivating the carbon. Dewatering screen 26 may be provided as a two-stage screen, wherein a first stage removes a majority of the liquid fraction 52 from the spent carbon solids fraction 55 , and a second stage removes residual caustic and/or cyanide from the solids fraction 55 of spent carbon before it enters a regeneration kiln 35 or wash vessel. Accordingly, equipment in the carbon regeneration system 30 ′ is not damaged.
[0073] FIG. 12 schematically illustrates a continuous elution process 20 according to some embodiments. First, a slurry 51 of descaled loaded carbon 50 and a caustic strip solution comprising water and cyanide is produced 1048 . The slurry 51 may be formed and stored in a holding tank 60 . The slurry 51 is then pumped 1050 into the splash vessel 22 which is configured to elevate the temperature and/or pressure of the descaled loaded carbon/strip solution slurry 51 . After increasing the temperature and/or pressure 1052 of the slurry 51 in the splash vessel 22 , a hot pressurized slurry 51 a of loaded carbon/strip solution is formed and moved 1054 from the splash vessel 22 to the continuous elution vessel 24 . The hot pressurized slurry 51 a is kept within the vessel 24 for an increased residence time 1056 , for instance, by providing a fluidized bed 320 alone or in combination with a plurality of baffles 318 in order to elongate the physical travel path of the hot pressurized slurry 51 a between the inlet 304 of the vessel 24 and the outlet 328 . The physical travel path may be for instance, a serpentine flow path 51 b as shown.
[0074] During its time of residence within the continuous elution vessel 24 , the loaded carbon in the hot pressurized slurry 51 a is stripped of its adsorbed precious metal by reagents in the caustic strip solution. Accordingly, the caustic strip solution dissolves the precious metal into itself thereby forming an electrolyte solution 53 . The electrolyte solution 53 is screened to remove carbon particulate therefrom and is extracted 1064 from the continuous elution vessel 24 . Subsequently, the electrolyte solution 53 is fed 1066 to a continuous electrowinning system 40 ′ (e.g., into a continuous electrolytic metal extraction cell 42 ) for precious metal recovery. During the electrowinning process 1068 (see FIG. 19 ), barren solution 54 is continuously removed 1070 from the continuous electrowinning system 40 ′ and pumped 1072 back into the continuous elution vessel 24 either directly, or indirectly (e.g., via a barren solution holding tank (not shown) or immersion heater 27 ).
[0075] Solution and carbon are continuously removed from the continuous elution vessel 24 , and the liquid fraction of the solution “flashed” or at least partially vaporized 1058 with a valve 29 before entering the flash vessel 25 . The process 20 further comprises recovering 1060 heated steam from the rapid evaporation of exiting spent slurry 51 c , and piping 1062 the steam back to the splash vessel 22 in order to efficiently increase 1052 the temperature and/or pressure of the first vessel 22 . Concentrated spent slurry 51 d is removed 1074 from the flash vessel 25 , and then dewatered 1076 to separate the spent liquid fraction 52 from the spent solids fraction 55 . The solids fraction 55 comprises dewatered carbon which is sent 1078 to a carbon regeneration system 30 ′, and the spent liquid fraction 52 of the concentrated spent slurry 51 d is sent 1080 to the holding tank 60 for re-use.
[0076] It should be known that the particular features and suggested uses of the continuous elution systems 20 ′ and processes 20 shown and described herein are exemplary in nature and should not limit the scope of the invention. For example, fluidized bed 320 may be replaced with, or used in combination with one or more mechanical agitators (not shown) to suspend loaded carbon particulate. Moreover, the number of baffles 318 in the continuous elution vessel 24 may be greater or less than what is shown, in order to provide the residence times and flow rates required for a particular process. Additionally, one or more additional vessels 22 , 24 , 25 may be added to a continuous elution system 20 ′ and placed in series or parallel with other vessels 22 , 24 , 25 to increase throughput. For example, two or three continuous elution vessels 24 may be directly or indirectly coupled to each other in parallel, and placed in series between a single splash vessel 22 and a single flash vessel 25 .
[0077] FIG. 13 shows a continuous electrowinning process 40 according to some embodiments. The process 40 comprises continuously providing an electrolyte solution 53 , continuously feeding the electrolyte solution 53 to a continuous electrolytic metal extraction cell 42 , extracting cathode sludge concentrate 53 f from the cell 42 in a sludge removal stream 53 g , continuously extracting barren solution 54 from the cell 42 and using said barren solution 54 to feed a continuous elution vessel 24 within a continuous elution process 20 .
[0078] As shown in FIGS. 14-18 , the continuous electrowinning system 40 ′ largely comprises a continuous electrolytic metal extraction cell 42 comprising a cell body 406 having a first end 440 , a second end 480 , one or more sidewalls 482 extending therebetween, a base 404 having one or more mounts 402 , at least one inlet 410 for receiving a continuous influent stream of a precious metal-containing electrolyte solution 53 , at least one first outlet 420 for providing continuous egress of a spent electrolyte stream 53 d and barren solution 54 contained therein, and at least one second outlet 430 for providing egress of cathode sludge concentrate 53 f collected within the cell 42 . The second outlet 430 may be configured for continuous egress of collected cathode sludge concentrate 53 f , or the second outlet 430 may be configured for intermittent egress of said collected cathode sludge concentrate 53 f . Within the cell body 406 is provided a first chamber 405 , a second chamber 407 , a third chamber 408 , and a residence chamber 460 comprising one or more elongated channels 462 . The channels 462 are configured to increase residence time of the electrolyte solution 53 and provide a forced flow electrolyte stream 53 b of electrolyte solution 53 therein which is strong enough to dislodge and/or displace cathodic sludge concentrate which forms and builds up within the channels 462 . The one or more channels 462 may comprise, for example, a portion of a helix, double-helix, coil, spiral, serpentine, spline, compound curve, and may extend in curvilinear paths. In some embodiments, as shown, the residence chamber 460 may be concentrically situated between the first chamber 405 and the third chamber 408 . The first chamber 405 may be configured to be devoid of electrolyte and/or cathodic sludge concentrate during operation, and may generally serve as a space-filler bounded between first end 440 , inner anode 477 , and baffle 450 . The space filling first chamber 405 generally provides channels 462 within the residence chamber 460 with a larger radius, thereby increasing the overall effective length and total surface area of the channels 462 exposed to forced flow electrolyte streams 53 b contained therewithin. The third chamber 408 serves to temporarily hold and/or transport spent electrolyte streams 53 d from within the cell 42 to one or more first outlets 420 . In some embodiments, to reduce material costs, the first end 440 may be configured as an annular panel having a central opening exposing the first chamber 405 , rather than as a solid continuous circular panel as shown. The one or more first outlets 420 may be provided at an upper portion of the cell 42 where overflow is likely to be more clarified and free from cathode sludge concentrate.
[0079] Each channel 462 may be defined between at least one anode 474 , at least one cathode 472 , and one or more insulators 476 extending therebetween. In the particular embodiment shown, one or more anodes 474 and one or more cathodes 472 are provided as sleeve portions which alternate concentrically between an outer anode 479 and an inner anode 477 with each sleeve portion having a different radius. The anodes 474 and cathodes 472 are radially separated and maintain a uniform spacing by one or more spacing protuberances 473 projecting from said one or more cathodes 472 . It should be understood, that while not shown, the one or more protuberances 473 may alternatively extend from the anodes 474 alone, or may extend from both anodes 474 and cathodes 472 without limitation. However, by providing protuberances 473 on the one or more cathodes 472 , a small amount of extra cathodic surface area is provided for precipitating cathodic sludge concentrate out of the forced flow electrolyte stream 53 b during electrolysis. The one or more insulators 476 prevent short circuit between the negatively charged anodes 474 and positively charged cathodes 472 and may serve as flexible, tolerance-compensating gaskets which delineate the cross-sectional boundary of each channel 462 and build/concentrate the forced flow electrolyte stream 53 b within each channel 462 .
[0080] As shown in FIG. 18 , each anode 474 may communicate with one or more anode terminals 442 . Anode terminals 442 may comprise, for example and without limitation, a fastener 442 a such as a pin or screw, a clamping member 442 b such as a nut, flange, or head, a terminal lead 442 c connected to a ground or power source, a conductive washer 442 d or other clamping member, an insulative bushing 442 e to prevent electrical currents from passing to surrounding portions of the cell 42 , a thread or equivalent securing feature 442 f provided on said fastener 442 a , a conductive support 442 h comprising a complimentary thread or equivalent securing feature 442 g for communicating with said thread or equivalent securing feature 442 f , and a receiving portion 442 i provided within the conductive support 442 h for engaging and supporting one or more anodes 474 . In the particular embodiment shown, anodes 474 are generally tubular cylindrical sleeves and therefore, receiving portions 442 i may be provided as small straight or generally arcuate slits. However, other equivalent interfaces are envisaged, particularly for non-cylindrical or non-tubular anodes 474 and cathodes 472 . For example, instead of slits, receiving portion 442 i may comprise a plurality of conductive clamps, spring clips, or pegs extending from the support 442 h which straddle and secure an anode 474 thereto.
[0081] In some embodiments, the continuous electrowinning system 40 ′ may be provided with a cylindrical cell body 406 , a flat circular upper first end 440 , and a generally frustoconical lower second end 480 . The frustoconical shape of the lower second end 480 generally aids in channeling collected heavy cathode sludge concentrate 53 f to the second outlet 430 for removal. The first end 440 may be secured to the cell body 406 via an annular flange 445 which may be electrically neutral or positively charged with the rest of cathodic cell body 406 . The first end 440 may comprise a series of sandwiched panels, such as one or more ground or electrically-neutral panels 447 , one or more anodic panels 444 , and one or more insulative panels 446 . In some embodiments the one or more insulative panels 446 may comprise a gasket, such as a polytetrafluoroethylene (PTFE) insulating gasket. One or more fasteners 441 or adhesives may be provided to secure the first end 440 to the body 406 and/or to secure sandwiched panels 444 , 446 , 447 together. For example, a series of fasteners 441 may be provided around a perimeter of the first end 440 to secure the first end 440 to the flange 445 . The fasteners 441 may be insulated, for example, with a sheath, coating, bushing, or washer of non-conductive material such as high molecular weight polyethylene (HMWPE), polyvinylidene fluoride (PVDF), polypropylene, or polyvinylchloride (PVC). Moreover, the fasteners 441 may serve the dual purpose of securing the first end 440 to the body 406 and also securing sandwiched panels 444 , 446 , 447 together.
[0082] In use, an influent stream of electrolyte solution 53 at a higher-than-ambient pressure and temperature continuously enters the cell 42 via inlet 410 . The electrolyte solution 53 may contain metal ions of copper, gold, silver, platinum, lead, zinc, cobalt, manganese, aluminum, or uranium, without limitation. The continuous electrowinning system 40 ′ is preferably maintained at a higher-than-ambient temperature (e.g., around 88 degrees Celsius) and/or pressure. The influent stream of electrolyte solution 53 may come from an upstream electrolyte holding tank (not shown), a continuous elution system 20 ′, or a combination thereof. In some embodiments, the inlet 410 may be formed from a portion of a pipe or tubing having one or more sidewalls 412 and may further comprise an inlet mount 414 having a flange, seal, valve, pipe fitting, or equivalent connector for integration with the continuous elution system 20 ′. Inlet 410 comprises one or more openings 413 (e.g., through said one or more sidewalls 412 ), which are configured to feed said one or more channels 462 of the residence chamber 460 with incoming electrolyte solution 53 . Though not shown, a plurality of openings 413 may be provided per channel 462 . In the event multiple channels 462 and a single inlet 410 is employed as shown, the influent stream of electrolyte solution 53 may be split into a plurality of dispersed influent streams 53 a , each entering different channels 462 . Alternatively, while not shown, a separate inlet 410 may be provided for each channel 462 . The openings 413 may be configured to provide uniform or non-uniform flow rates across each channel 462 or provide similar electrolyte residence times for each channel 462 . As clearly shown in FIG. 17 , one or more insulators 417 (e.g., an insulation pad) may be placed between one or more sidewalls 412 of the inlet 410 and the first end 440 of the cell body 460 . The one or more insulators 417 may encircle the one or more openings 413 to ensure that incoming electrolyte solution 53 from dispersed influent streams 53 a does not form, plate, or sludge within the openings 413 , particularly adjacent cathodes 472 .
[0083] In some embodiments, channels 462 may be configured to allow the dispersed influent streams 53 a of electrolyte solution 53 to flow forcedly through the channels 462 in a forced flow electrolyte stream 53 b which follows a uniform helical or spiral path as shown. However, while not shown, the channels 462 may also be configured to direct the dispersed influent streams 53 a along straight paths, serpentine paths, compound curve paths, or complex 3D-spline curve paths so long as they can support a forced flow electrolyte stream 53 b therein and provide a sufficient residence time of electrolyte between an anode 474 and cathode 472 .
[0084] Channels 462 may shrink or grow in circumference or change in overall or cross-sectional shape and/or size as they extend within the residence chamber 460 ; however, it is preferred that channels 462 remain uniform in cross-section, direction, and/or anode-cathode spacing throughout their entire length. While not shown, since channels 462 located at greater radial distances from the center of the cell 42 are longer and will generally have higher residence times than inner channels 462 , the number of turns of inner channels 462 (e.g., channels adjacent inner anode 477 and first chamber 405 ) may be adjusted to be greater than the number of turns for outer channels 462 (e.g., channels more proximate the outer anode 479 and third chamber 408 ). In other words, while not shown, inner portions of residence chamber 460 may be greater in height than outer portions of residence chamber 460 , in order to lengthen the effective length of inner channels 462 (adjacent the first chamber 405 ). Portions of baffle 450 adjacent the residence chamber 460 and third chamber 408 are generally open so as to allow channels 462 to continuously deliver spent electrolyte streams 53 d to the third chamber 408 and collected cathode sludge concentrate 53 f formed in the channels 462 to the second chamber 407 .
[0085] As shown in FIG. 16 , baffle 450 may comprise an anodic layer 452 , a middle electrically-neutral insulator 454 to support said one or more anodes 474 and cathodes 472 , and a support structure 456 for supporting the insulator 454 and anodic layer 452 . The insulator 454 may be made of a chemically-robust material such as ultra-high molecular weight polyethylene (UHMWPE) and may be cruciform in shape as shown. A plurality of receiving portions 458 such as notches may be provided to the insulator 454 to hold, space, insulate, and support the one or more anodes 474 and cathodes 472 ; however, other holding means such as pegs, spring clips, or clamps may be provided. The insulator 454 may be connected to the support structure 456 with one or more fasteners, adhesives, or other connecting means, and the support structure 456 may be connected to the body 406 by conventional means such as bolting, forming, adhering, welding, or supporting on a flange or shelf. The anodic layer 452 may serve to close off the first chamber 405 and prevent electrolyte 53 in the forced flow electrolyte stream 53 b from entering said first chamber 405 . In some embodiments, the support structure 456 may be a lattice structure such as a mesh screen or supporting member such as a crossbar which spans a width of the cell body 406 . Support structure 456 is generally configured not to inhibit electrolyte flowing from the channels 462 to the third chamber 408 , or inhibit the passage of cathode sludge concentrate 53 f to the second chamber 407 .
[0086] As electrolyte solution 53 forcibly flows through the one or more channels 462 in the residence chamber 460 , a large electric potential is placed between the one or more anodes 474 and one or more cathodes 472 in order to effectively “plate-out” sludge concentrate onto the one or more cathodes 472 . However, by varying operating parameters such as residence time, electric current, electrolyte flow rate, temperature, pressure, electrolyte concentration/composition, and/or smoothness/material/coating of each cathode(s) 472 , the channels 462 may be configured such that cathodic sludge concentrate initially forms on or adjacent to the one or more cathodes 472 , but will not actually bond or “plate” to the cathodes 472 and will instead flush down the channels 462 and/or become suspended in the forced flow electrolyte streams 53 b . Any sludge concentrate that may settle to bottom of a channel 462 may also be washed down and eventually swept out of the channels 462 and into second chamber 407 by the forced flow electrolyte streams 53 b . Sludge concentrate may be flushed out of the one or more channels 462 by virtue of: gravitational forces acting on inclined surfaces, high flow rates of forced flow electrolyte streams 53 b passing through the one or more channels 462 , increased turbulence within each channel 462 , and/or by virtue of small cross-sectional areas provided to each channel 462 .
[0087] After the forced flow electrolyte streams 53 b pass through the one or more channels 462 , the outflow 53 c of the residence chamber 460 will generally comprise a liquid carrier component of barren solution 54 which is substantially-free of dissolved precious metal, and a solid precipitate component comprising cathodic sludge concentrate which has been discharged from the channels 462 by the forced flow electrolyte stream 53 b . The heavier solids may follow a sludge precipitate stream 53 e before settling in a mass of collected cathode sludge concentrate 53 f within the second chamber 407 adjacent the second end 480 . Barren solution 54 travels via spent electrolyte stream 53 d into the third chamber 408 and continuously leaves the cell 42 through outlet 420 . In embodiments where the cell body 406 is cathodic, some residual plating or cathodic sludge concentrate formation may occur within the third chamber 408 (for example, on or around inner portions of cathodic sidewall(s) 482 ). However, any cathode sludge concentrate 53 f formed within the third chamber 408 will typically settle and eventually end up in second chamber 407 with the rest of the collected cathode sludge concentrate 53 f.
[0088] The first outlet 420 may be formed from a portion of a pipe or tubing having one or more sidewalls 422 and may further comprise a first outlet mount 424 having a flange, seal, valve, pipe fitting, or equivalent connector for integration with a continuous elution system 20 ′. When in use, an effluent stream of barren solution 54 continuously leaves the cell body 406 through said first outlet 420 at which point it may enter a barren solution holding tank (not shown), be discarded, return to a continuous elution system 20 ′, or undergo further processing.
[0089] Captured cathode sludge concentrate 53 f may be removed from the cell 42 intermittently or continuously via second outlet 430 . The underflow, or sludge removal stream 53 g of cathode sludge concentrate 53 f may proceed to a holding tank, be pumped away for further refining, or may be dumped into a container and transported to a smelter. In some embodiments, the second outlet 430 may be formed from a portion of a pipe or tube having one or more sidewalls 432 and may further comprise a second outlet mount 434 having a flange, seal, valve, pipe fitting, nozzle, tap, or equivalent connector for integration with a holding tank or smelting apparatus.
[0090] The cross-section of residence chamber 460 may vary, so long as one or more channels 462 therein are formed between at least one anode 474 and at least one cathode 472 which are separated from each other by one or more insulators 476 . Channels may extend linearly (resembling an elongated pipe), helically, in a cascade of connected, horizontally-arranged, and vertically-displaced “figure-8s”, or in any continuous path in 3-D space which is configured to provide a “forced flow” of electrolyte solution. In order to assist with outgassing of air which could get caught in the channels 462 and also prevent the backup of precipitated sludge concentrate within the channels, it is preferred that the continuous path the channels follow in 3-D space be free of sharp bends, abrupt turns, overhangs, high spots, and/or tightly wound corners which may be prone to air capture and clogging. In some embodiments, a residence chamber 460 may comprise one or more channels 462 therein which simply extend as long straight pipe sections tilted at an angle with respect to horizontal.
[0091] FIG. 19 schematically illustrates a continuous electrowinning process 40 according to some embodiments. The process 40 comprises providing 1082 an electrolyte solution 53 having an elevated temperature or pressure with respect to ambient conditions. The electrolyte solution 53 may be produced from a continuous elution process 20 and may comprise water, cyanide, caustic, and a dissolved metal (e.g., gold, copper, silver, platinum, aluminum, lead, zinc, cobalt, manganese, or uranium) therein. The electrolyte solution 53 is continuously fed 1084 (e.g., at a predetermined flow rate) into a continuous electrolytic metal recovery cell 42 which is preferably maintained 1086 at a higher-than-ambient temperature and/or pressure. In some embodiments, the cell 42 may comprise a series of nested anode sleeves 474 and cathode sleeves 472 , wherein adjacent sleeves have a different electrical potential or charge. In a preferred embodiment, the sleeves are spaced concentrically and radially evenly with respect to each other so that any two neighboring sleeves hold an opposite charge 1088 . One or more insulators 476 may be placed between the anodes 474 and cathodes 472 to define a plurality of channels 462 (e.g., helical channels) and simultaneously prevent arcing between the anodes and cathodes. The process 40 further comprises subjecting 1090 the electrolyte solution 53 to a longer residence time within a continuous electrolytic metal recovery cell 42 . This may be achieved by providing one or more elongated channels 462 between the anode 474 and cathode 472 sleeves, which extend in smooth, continuous, and uninterrupted helical paths. It should be known that residence time may also be increased by alternatively employing long tubular straight channels. Electrolyte solution 53 maintained within the channels 462 is forced through the channels 462 and walls thereof by small pressure differentials between the inlet 110 and the first 120 outlet and/or small pressure differentials between the inlet 110 and the second 130 outlet. As the electrolyte solution 53 moves through the channels 462 , cathodic sludge concentrate precipitates out of the electrolyte solution 53 until the solution becomes weaker in concentration and eventually substantially-free of precious material 1092 . Precipitating concentrate from the sludge precipitate stream 53 e is continuously collected 1094 within second chamber 407 , and collected cathode sludge concentrate 53 f may be extracted 1098 continuously or intermittently or a combination thereof. A stream of barren solution 54 (which is substantially devoid of precious metal) is continuously extracted 1096 from the cell 42 via outlet 420 , and may be fed to a continuous elution vessel 24 within a continuous elution process 20 .
[0092] FIG. 20 shows a carbon regeneration process 30 according to some embodiments. A solids fraction 55 of concentrated spent slurry 51 d comprising spent de-watered carbon is sifted with a screen 32 to separate out spent carbon fines 55 b . The spent carbon fines 55 b are placed in a carbon fines holding tank 34 . The remaining course spent carbon 55 a is sent to a regeneration kiln 35 (or other means for regeneration such as a chemical, steam, or biological process). Hot reactivated carbon 55 c is removed from the regeneration kiln 35 and quenched in a carbon quench tank 36 . A slurry of cooled regenerated carbon and fluid moves to a dewatering screen 37 via pump 33 . After passing through dewatering screen 37 , dewatered activated/reactivated carbon 56 is moved to a continuous carbon loading/adsorption process 70 . The fluid underflow, which comprises cool reactivated carbon slurry 55 d , is moved to the carbon fines holding tank 34 .
[0093] FIG. 21 shows a continuous metal recovery system 100 ′ according to some embodiments of the invention comprising a continuous acid wash system 10 ′, a continuous elution system 20 ′, a continuous electrowinning system 40 ′, and a carbon regeneration system 30 ′. FIGS. 22 and 23 serve to compare scale plant layouts and overall footprints. FIG. 22 shows the system 100 ′ for the continuous recovery of metals according to FIG. 21 and FIG. 23 comprises a conventional system 9000 ′ for the batch recovery of metals using “batch” process steps. As can be seen from FIGS. 22 and 23 , the system 100 ′ according to the invention is smaller in size than the conventional system 9000 ′ depicted in FIG. 23 . In addition to smaller size, system 100 ′ is also more efficient and environmentally-friendly.
[0094] FIG. 24 shows an alternative to the washing tanks 200 , 200 ′, 200 ″ shown in FIGS. 6-8 . In the embodiment shown, an acid wash tank 2000 is provided, which may replace acid wash tank 200 . Acid wash tank 2000 comprises a wash chamber 2020 having a fluidized bed panel 2021 spanning the length of the wash chamber 2020 with pore sizes smaller than the mean particle size of loaded/reloaded carbon, one or more adjustable mounts 2007 , 2009 which may be individually raised, lowered, or pivoted on a rack or linkage (not shown for clarity) to change the inclination angle of the chamber 2020 with respect to a skid 2002 , a recirculation inlet 2023 a provided below the fluidized bed panel 2021 , and a recirculation outlet 2023 b provided above the fluidized bed panel 2021 . Recirculation outlet 2023 b comprises one or more overflow outlets 2027 , each provided with at least one washable/replaceable recycle screen 2008 , which maintains loaded/reloaded carbon 57 within the chamber 2020 and filters exiting dilute acid solution 57 c . Recycle screens 2008 may be conveniently provided between bolted flange members of the overflow outlets 2027 and may comprise built-in peripheral gaskets. FIGS. 25 and 26 show more detailed views of the chamber 2020 shown in FIG. 24 .
[0095] Recirculation inlet 2023 a may comprise one or more adjustable nozzles 2011 which serve to fluidize loaded/reloaded carbon 57 . The nozzles 2011 may be individually or collectively angularly adjusted and “set” to a fixed angle, in order to: compensate for various inclinations of the chamber 2020 , prevent buildup of loaded/reloaded carbon 57 , and counteract backflow within the chamber 2020 caused by eddy currents surrounding interior baffles 2018 . Chamber 2020 may, as shown, be constructed in clamshell form, with a number of fasteners 2004 connecting upper and lower clamshell portions together. One or more additional gaskets may be employed between the upper and lower clamshell portions to form a seal, or the fluidized bed panel 2021 itself may be provided with peripheral gasketing material properties to provide a seal between the upper and lower clamshell portions.
[0096] A first filter 2001 is provided at an inlet 2022 to the acid wash tank 2000 . The first filter 2001 comprises a housing 2003 which serves to collects influent loaded/reloaded carbon slurry 57 ′, a first screen 2026 which serves to separate loaded/reloaded carbon 57 from carrier fluid 57 f present in the slurry 57 ′, a first filter outlet 2006 which serves to transfer strained loaded/reloaded carbon 57 from within the upper housing 2003 to the wash chamber 2020 , a recirculation tank 2029 which collects carrier fluid 57 f separated from the liquid fraction of the influent slurry 57 ′, and one or more clamps 2005 which removably attach the housing 2003 to the recirculation tank 2029 with the first screen 2026 extending therebetween, thereby allowing periodic cleaning and/or replacing of the first screen 2026 . Recirculation tank 2029 may be configured to continuously redistribute carrier fluid 57 f to a holding tank (not shown) or may simply comprise a valve for batch removal of the collected carrier fluid 57 f.
[0097] A second filter 2024 , similar to the first filter 2001 , is provided adjacent a first channel 2082 extending from the fluidized bed panel 2021 to an outside portion of the wash chamber 2020 . First channel 2082 is configured to provide egress of acid-rinsed loaded carbon 57 a resting on/around/above fluidized bed panel 2021 after it has undergone a predetermined residence time of acid washing within the chamber 2020 . The acid-rinsed loaded carbon 57 a is filtered by a second screen 2036 , and the strained solids fraction of the acid-rinsed loaded carbon 57 a exits a discharge outlet 2028 . The acid-rinsed loaded carbon exiting the discharge outlet 2028 may be captured and contained by a holding tank 2060 and subsequently transported (via pump 2030 ) to a downstream process (e.g., aqueous rinse cycle). Alternatively, the acid-rinsed loaded carbon exiting the discharge outlet 2028 may directly enter a downstream process (e.g., pour into another aqueous rinse tank 200 ′ without an intermediate holding tank 2060 and pump 2023 ). Holding tank 2060 advantageously serves as a buffer which maintains a level of process control and prevents too much carbon feed to downstream processes.
[0098] In use, replenished dilute acid solution 57 c ′ (obtained by filtering acid-rinsed loaded carbon 57 a with second screen 2036 ) enters recirculation tank 2039 and is pumped to chamber 2020 via a pump 2030 . The replenished dilute acid solution 57 c ′ enters the recirculation inlet 2023 a and then passes upwards through fluidized bed panel 2021 via nozzles 2011 . The replenished dilute acid solution 57 c ′ suspends incoming loaded/reloaded carbon 57 , and moves the loaded/reloaded carbon 57 through the chamber 2020 and around baffles 2011 for a predetermined residence time. The replenished dilute acid solution 57 c ′ passes through recycle screens 2008 and filtered dilute acid solution 57 c re-enters the recirculation tank 2039 via recirculation outlet 2033 b . Residence time of the loaded/reloaded carbon 57 may be increased or decreased by adjusting the inclination angle of the chamber 2020 and/or adjusting the angular orientation of nozzles 2011 . For a fixed, non-variable metal extraction process, the inclination angle of chamber 2020 and angular positions of nozzles may be preset by the manufacturer and permanently fixed in the optimum configuration to yield the most efficient residence time for said process.
Example 1
[0099] A water-based, loaded carbon slurry 57 comprising approximately 30-300 oz/ton gold and approximately 30% wt/wt, activated coconut shell carbon is delivered to a continuous acid wash system 10 ′. First, inorganic components, namely calcium and magnesium carbonate, are removed from the loaded carbon by fluidizing a bed of loaded active carbon with a dilute aqueous acid solution comprising approximately 1-5 wt % hydrogen chloride (HCl) and/or nitric acid (HNO 3 ) in an acid wash tank 12 , 200 . The loaded active carbon is continuously transferred from the acid wash tank to an aqueous rinse tank 14 , 200 ′ where the loaded active carbon is fluidized and cleaned with water. The loaded carbon is subsequently continuously transferred from the aqueous rinse tank 14 , 200 ′ to a caustic rinse tank 16 , 200 ″. The pH of the loaded active carbon delivered to the caustic rinse tank is raised above 10 by a caustic solution comprising approximately 1-3 wt % sodium hydroxide.
[0100] The basic descaled loaded carbon 50 is fed continuously to a splash vessel 22 within a continuous elution system 20 ′ via a transfer medium of caustic strip solution comprising approximately 1 wt % caustic (NaOH) and 0.1 wt % cyanide (NaCN). The splash vessel 22 is generally held at an operating temperature between approximately 100 and 200 degrees Fahrenheit (° F.), and at a pressure of approximately atmospheric level. The loaded carbon is transferred from the splash vessel 22 to the continuous elution vessel 24 , where the gold is removed from the carbon (i.e., gold dissolution). The continuous elution vessel 24 operates at roughly 300 degrees Fahrenheit (° F.), which temperature is achievable by elevating the strip solution pressure to roughly 70 psi (gauge). The continuous elution vessel 24 continuously discharges into a lower pressure flash vessel 25 . A drop in pressure between the continuous elution vessel 24 and flash vessel 25 causes rapid flash vaporization of a portion of the effluent caustic strip solution. Steam generated is channeled to the splash vessel 22 , thereby simultaneously heating the splash vessel 22 and cooling the flash vessel 25 . Spent carbon, (e.g., comprising less than 1 oz/ton gold), is continuously moved out of the continuous elution system 20 ′ and into a regeneration process 30 .
[0101] The approximately 300° F. pressurized caustic strip solution is filtered by one or more screens or filters 324 to remove barren carbon particulate and form electrolyte solution 53 , which is then passed through a continuous electrolytic metal extraction (i.e., electrowinning) cell 42 . The electrolyte solution 53 is forced (via the increased pressure provided by the continuous elution vessel 24 ) through at least one channel 462 having a fixed helical path between a cylindrical sleeve anode 474 and a cylindrical sleeve cathode 472 . A voltage between approximately 2 and 4 volts is passed between the anode 474 through the electrolyte solution 53 and the cathode 472 , thereby depositing cathode sludge concentrate 53 f on surfaces of the cathode 472 . The velocity of the electrolyte solution 53 creates a forced flow electrolyte stream 53 b within the channel 462 which continuously washes the collected cathode sludge concentrate 53 f which may form and collect on the cathode's surfaces to the conical bottom of the cell 42 , where it may be removed at the operator's leisure or continuously via a control valve.
[0102] A contractor or other entity may provide a system 100 ′ or process 100 for the continuous recover of metals in part or in whole as shown and described. For instance, the contractor may receive a bid request for a project related to designing a continuous metal recovery system 100 ′ or process 100 , or the contractor may offer to design such a system 100 ′ or a process 100 for a client. The contractor may then provide, for example, any one or more of the devices or features thereof shown and/or described in the embodiments discussed above. The contractor may provide such devices by selling those devices or by offering to sell those devices. The contractor may provide various embodiments that are sized, shaped, and/or otherwise configured to meet the design criteria of a particular client or customer. The contractor may subcontract the fabrication, delivery, sale, or installation of a component of the devices or of other devices used to provide such devices. The contractor may also survey a site and design or designate one or more storage areas for stacking the material used to manufacture the devices. The contractor may also maintain, modify, or upgrade the provided devices. The contractor may provide such maintenance or modifications by subcontracting such services or by directly providing those services or components needed for said maintenance or modifications, and in some cases, the contractor may modify an existing metal recovery process 9000 or system 9000 ′ with a “retrofit kit” to arrive at a modified process or system comprising one or more method steps, devices, or features of the systems 100 ′ and processes 100 discussed herein.
[0103] Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed invention. For example, particulates and carriers other than carbon (e.g., polymers or ion exchange resins) may be used with the disclosed systems and processes. Moreover, reagents other than water, cyanide, and caustic may be used to wash, descale, or strip the particulates. Furthermore, the disclosed systems and processes may be used to recover numerous types of materials including, but not limited to copper, gold, silver, platinum, uranium, lead, zinc, aluminum, chromium, cobalt, manganese, rare-earth and alkali metals, etc. Accordingly, it is to be understood that the drawings and descriptions herein are proffered by way of example to facilitate comprehension of the invention and should not be construed to limit the scope thereof.
[0000]
Reference numeral identifiers
10
Continuous acid wash process
10′
Continuous acid wash system
12
Acid wash tank
13
Pump
14
Aqueous rinse tank
16
Caustic rinse tank
20
Continuous elution process
20′
Continuous elution system
21
Steam return
22
Splash vessel
23
Pump
24
Continuous elution vessel
25
Flash vessel
26
Dewatering screen
27
Immersion heater
28a
Influent manifold
28b
Effluent manifold
29
Valve
30
Carbon regeneration process
30′
Carbon regeneration system
32
Screen
33
Pump
34
Carbon fines holding tank
35
Regeneration kiln
36
Carbon quench tank
37
Dewatering screen
40
Continuous electrowinning process
40′
Continuous electrowinning system
42
Continuous electrolytic metal extraction cell
50
Descaled loaded carbon (or caustic/basic slurry thereof)
51
Slurry of strip solution and descaled loaded carbon
51a
Heated and/or pressurized slurry
51b
Serpentine flow path of slurry
51c
Spent slurry
51d
Concentrated spent slurry
52
Liquid fraction of concentrated spent slurry
53
Electrolyte solution
53a
Dispersed influent stream
53b
Forced flow electrolyte stream
53c
Residence chamber outflow
53d
Spent electrolyte stream
53e
Sludge precipitate stream
53f
Cathode sludge concentrate
53g
Sludge removal stream
54
Barren solution (i.e., spent electrolyte)
55
Solids fraction of concentrated spent slurry (e.g., de-water
55a
Course spent carbon
55b
Spent carbon fines
55c
Hot reactivated carbon
55d
Cool reactivated carbon slurry
56
Activated/reactivated carbon
57′
Loaded/reloaded carbon slurry
57
Loaded/reloaded carbon
57a
Acid-rinsed loaded carbon
57b
Rinsed loaded carbon
57c, 57c′
Dilute acid solution
57d, 57d′
Aqueous rinse solution
57e
Caustic rinse solution
57f
Carrier fluid
60
Holding tank
70
Continuous carbon loading/adsorption process
70′
Continuous carbon loading/adsorption system
100
Process for the continuous recovery of metals
100′
System for the continuous recovery of metals
200
Acid wash tank
200′
Aqueous rinse tank
200″
Caustic rinse tank
220
First chamber
221
First fluidized bed panel
222
First inlet
223a
First recirculation inlet
223b
First recirculation outlet
224
First weir
226
First screen
227
First overflow outlet
228
First discharge outlet
229
First recirculation tank
230
Second chamber
231
Second fluidized bed panel
232
Second inlet
233a
Second recirculation inlet
233b
Second recirculation outlet
234
Second weir
236
Second screen
237
Second overflow outlet
238
Second discharge outlet
239
Second recirculation tank
240
Third chamber
241
Third fluidized bed panel
242
Third inlet
243a
Third recirculation inlet
243b
Third recirculation outlet
244
Third weir
246
Third screen
247
Third overflow outlet
248
Third discharge outlet
249
Third recirculation tank
251
Acid overflow
253
Drained acid return
254
Rinse water overflow
256
Drained rinse water return
257
Caustic rinse overflow
260
Bottom wall
266
Inner tubular wall
268
Outer tubular wall
282
First channel
284
Second channel
286
Third channel
301
Inlet seal
302
Inlet mount
304
Inlet
306
First end
308
Second end
310
One or more sidewalls
312
Effluent port mount
314
Mounting member
316
Effluent port
318
One or more baffles
320
Fluidized bed panel
322
Influent port mount
324
Filter (e.g., disk screen)
326
Influent port
328
Outlet
329
Outlet seal
330
Outlet mount
340
Residence chamber
350
Fluidizing chamber
402
Mount
404
Base
405
First chamber
406
Cell body
407
Second chamber
408
Third chamber
410
Inlet
412
One or more inlet sidewalls
413
One or more openings
414
Inlet mount
417
One or more insulators
420
First outlet
422
One or more first outlet sidewalls
424
First outlet mount
430
Second outlet
432
One or more second outlet sidewalls
434
Second outlet mount
440
First end
441
Fastener
442
Anode terminal
442a
Fastener
442b
Clamp
442c
Terminal lead
442d
Conductive washer
442e
Insulative bushing
442f
Thread or equivalent securing feature
442g
Complimentary thread or securing feature
442h
Conductive support
442i
Receiving portion
444
Anodic panel
445
Cathodic flange
446
Insulative panel
447
Anodic panel
450
Baffle
452
Anodic panel
454
Anode/Cathode insulator
456
Anode/Cathode insulator support
458
One or more receiving portions
460
Residence chamber
462
One or more channels
472
Cathode
473
One or more protuberances
474
Anode
476
One or more insulators
477
Inner anode
479
Outer anode
480
Second end
482
One or more sidewalls
1000
Process for the continuous recovery of metals
1002-1046
Continuous acid wash steps
1048-1080
Continuous elution steps
1082-1100
Continuous electrowinning steps
2000
Acid wash tank
2001
First filter
2002
Skid
2003
Housing
2004
Fastener
2005
Clamp
2006
First filter outlet
2007
First adjustable mount
2008
Recycle screen
2009
Second adjustable mount
2011
Nozzle
2018
Baffle
2020
Chamber
2021
Fluidized bed panel
2022
Inlet
2023
Pump
2023a
Recirculation inlet
2023b
Recirculation outlet
2024
Second filter
2026
First screen
2027
Overflow outlet
2028
Discharge outlet
2029
Recirculation tank
2033b
Recirculation outlet
2036
Second screen
2039
Recirculation tank
2060
Holding tank
2082
First channel
9000
Conventional batch metal recovery process
9000′
Conventional batch metal recovery system
9100
Conventional batch acid wash process
9100′
Conventional batch acid wash system
9120
Acid wash vessel
9132
Pump
9134
Carbon transfer pump
9136
Pump
9140
Dilute acid tank
9150
Sump pump
9160
Neutralizing tank
9200
Conventional batch (Zadra strip) elution process
9200′
Conventional batch (Zadra strip) elution system
9220
Barren solution tank
9232
Carbon transfer pump
9234
Barren solution backup pump
9236
Barren solution pump
9237
Barren solution
9239
Hot barren solution
9240
Strip vessel
9250
Heating skid or equivalent heat exchanger
9300
Carbon regeneration process
9400
Conventional batch electowinning process
9400′
Conventional batch electowinning system
9420
Batch electrolytic metal recovery cell
(e.g., removable plate cathodes)
9421
Hot electrolyte solution
9430
Pump
9440
Electrowinning pump box
9500
Descaled loaded carbon
9530
Electrolyte solution
9540
Barren solution
9550
Spent carbon
9560
Activated/reactivated carbon
9570
Loaded or reloaded carbon
9700
Conventional batch carbon loading process
|
A system [ 100 ′] and process [ 100 ] for the continuous recovery of metals is disclosed. The system [ 100 ′] comprises a continuous acid wash system [ 10 ′], a holding tank [ 60 ], a continuous elution system [ 20 ′], a continuous electrowinning system [ 40 ′], a carbon regeneration system [ 30 ′], and a continuous carbon loading/adsorption system [ 70 ′]. The systems and methods disclosed overcome the disadvantages associated with current systems and processes which utilize batch process steps and equipment designed for batch processes. The systems [ 10′, 20′, 30 ′] are each configured to receive a continuous inflow of a solution or slurry and deliver a continuous outflow of a solution or slurry, without interruptions which are common with conventional metal recovery systems [ 9000′].
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of co-pending U.S. patent application Ser. No. 11/561,908, filed Nov. 21, 2006, which is herein incorporated by reference.
BACKGROUND OF INVENTION
Field of Invention
[0002] This invention generally relates to design structures, and more specifically, design structures for managing caches in a processing system.
[0003] Traditional processor designs make use of various cache structures to store local copies of instructions and data in order to avoid lengthy access times of typical DRAM memory. In a typical cache hierarchy, caches closer to the processor (level one or L1) tend to be smaller and very fast, while caches closer to the DRAM (L2 or L3) tend to be significantly larger but also slower (longer access time). The larger caches tend to handle both instructions and data, while quite often a processor system will include separate data cache and instruction cache at the L1 level (i.e. closest to the processor core). All of these caches typically have similar organization, with the main difference being in specific dimensions (e.g. cache line size, number of ways per congruence class, number of congruence classes).
[0004] In the case of an L1 Instruction cache, the cache is accessed either when code execution reaches the end of the previously fetched cache line or when a taken (or at least predicted taken) branch is encountered within the previously fetched cache line. In either case, a next instruction address is presented to the cache. In typical operation, a congruence class is selected via an abbreviated address (ignoring high-order bits), and a specific way within the congruence class is selected by matching the address to the contents of an address field within the tag of each way within the congruence class. Addresses used for indexing and for matching tags can use either effective or real addresses depending on system issues beyond the scope of this discussion. Typically, low order address bits (e.g. selecting specific byte or word within a cache line) are ignored for both indexing into the tag array and for comparing tag contents. This is because for conventional caches, all such bytes/words will be stored in the same cache line.
[0005] Recently, Instruction Caches that store traces of instruction execution have been used, most notably with the Intel Pentium 4. These “Trace Caches” typically combine blocks of instructions from different address regions (i.e. that would have required multiple conventional cache lines). The objective of a trace cache is to handle branching more efficiently, at least when the branching is well predicted. The instruction at a branch target address is simply the next instruction in the trace line, allowing the processor to execute code with high branch density just as efficiently as it executes long blocks of code without branches. Just as parts of several conventional cache lines may make up a single trace line, several trace lines may contain parts of the same conventional cache line. Because of this, the tags must be handled differently in a trace cache.
[0006] In a conventional cache, low-order address lines are ignored, but for a trace line, the full address must be used in the tag. A related difference is in handling the index into the cache line. For conventional cache lines, the least significant bits are ignored in selecting a cache line (both index & tag compare), but in the case of a branch into a new cache line, those least significant bits are used to determine an offset from the beginning of the cache line for fetching the first instruction at the branch target. In contrast, the address of the branch target will be the first instruction in a trace line. Thus no offset is needed. Flow-through from the end of the previous cache line via sequential instruction execution simply uses an offset of zero since it will execute the first instruction in the next cache line (independent of whether it is a trace line or not). The full tag compare will select the appropriate line from the congruence class. In the case where the desired branch target address is within a trace line but not the first instruction in the trace line, the trace cache will declare a miss, and potentially construct a new trace line starting at that branch target.
[0007] For a trace cache design to function correctly and with a high level of performance, the trace formation methodology is critical to the design. Trace formation involves fetching instructions from a higher level memory, identifying and predicting all branches in the stream, creating a “basic block” of instructions from this and appending it to the current instruction trace. A basic block is defined as all instructions up to and including the first branch in an instruction stream.
SUMMARY OF THE INVENTION
[0008] This invention contemplates that branches are predicted taken or not taken using a highly accurate branch history table (BHT). Branches that are predicted not taken are appended to a trace buffer and the next basic block is constructed from the remaining instructions in the fetch buffer. Branches that are predicted taken flush the remaining fetch buffer and the next address is determined using a Branch Target Address Register (BTAC). This address is used to fetch the next instruction stream that will be used to build the next basic block. Multiple basic blocks are typically added to the same trace line, within the constraints of trace termination rules to be described below.
[0009] In one embodiment, a design structure embodied in a machine readable storage medium for at least one of designing, manufacturing, and testing a design is provided. The design structure generally includes an apparatus, which includes a computer system central processor, layered memory operatively coupled to said central processor and accessible thereby, said layered memory having a level one cache storing in interchangeable locations both conventional cache lines of sequential instructions and trace cache lines of predicted branch instructions, and circuitry operatively connected to said layered memory and generating data to be stored in said level one cache, said circuitry distinguishing between conventional cache lines and trace cache lines.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Some of the purposes of the invention having been stated, others will appear as the description proceeds, when taken in connection with the accompanying drawings, in which:
[0011] FIG. 1 is a schematic representation of the operative coupling of a computer system central processor and layered memory which has level 1, level 2 and level 3 caches and DRAM;
[0012] FIG. 2 is a schematic representation of the organization of a L1 instruction cache;
[0013] FIG. 3 is a schematic representation of the instruction flow in generating a trace in accordance with this invention;
[0014] FIG. 4 is a schematic representation of the address flow in generating a trace in accordance with this invention; and
[0015] FIG. 5 is a flow diagram representing procedures involved in generating a trace for an instruction “A” that then branches to an instruction “B”.
[0016] FIG. 6 is a flow diagram of a design process used in semiconductor design, manufacture, and/or test.
DETAILED DESCRIPTION OF THE INVENTION
[0017] While the present invention will be described more fully hereinafter with reference to the accompanying drawings, in which a preferred embodiment of the present invention is shown, it is to be understood at the outset of the description which follows that persons of skill in the appropriate arts may modify the invention here described while still achieving the favorable results of the invention. Accordingly, the description which follows is to be understood as being a broad, teaching disclosure directed to persons of skill in the appropriate arts, and not as limiting upon the present invention.
[0018] The term “programmed method”, as used herein, is defined to mean one or more process steps that are presently performed; or, alternatively, one or more process steps that are enabled to be performed at a future point in time. The term programmed method contemplates three alternative forms. First, a programmed method comprises presently performed process steps. Second, a programmed method comprises a computer-readable medium embodying computer instructions which, when executed by a computer system, perform one or more process steps. Third, a programmed method comprises a computer system that has been programmed by software, hardware, firmware, or any combination thereof to perform one or more process steps. It is to be understood that the term programmed method is not to be construed as simultaneously having more than one alternative form, but rather is to be construed in the truest sense of an alternative form wherein, at any given point in time, only one of the plurality of alternative forms is present.
[0019] Instruction traces are created by appending basic blocks into the trace formation register. Various rules (stated below) have been defined for forming and ending traces. The purpose of the rules is to form traces that maximize performance while maintaining functionality. Once a trace has been formed, it is written into the trace cache where it can then be accessed for execution.
[0020] The present invention contemplates a method in which a cache runs in normal cache mode and then receives traces generated once branch prediction has “warmed up”. The address of the next trace line is stored at the end of the trace. Branch prediction is not required at the output of the cache, which saves logic/cycles by not having to re-predict the address. Only the address of the first basic block in a trace line is needed to access all basic blocks in the trace. Translation information is implicit within a traceline. Termination of a trace line occurs when the next basic block is taken from a page with different memory attributes than other basic blocks in the trace entry.
[0021] Termination of a trace line currently under construction occurs in a number of defined circumstances when: (1) a data dependent branch is encountered; (2) a bdnz instruction is encountered; (3) a branch with negative displacement is encountered; (4) a weakly predicted branch is encountered; (5) too many basic blocks are encountered; and (6) a basic block ends close to the end of a trace line.
[0022] New trace generation is initiated when a Trace Cache Miss occurs or when a conventional cache line is found in the cache and there is reason to believe that branch prediction is better now than when the line was placed in the cache. The address of the miss (or hit on conventional line) is used to fetch the next group of instructions from higher level memory (second level cache). This address is also used to access the “branch target address cache” (BTAC) which provides the next expected address that needs to be fetched. This next address will be the target of a branch from the first group of instructions or the next sequential address. Either way, this address is first used to access the trace cache and if another miss occurs then it is also sent to the second level cache and is considered a prefetch (i.e. predicted address).
[0023] Once instructions are returned from the second level cache they are placed in the instruction fetch register ( FIG. 3 ). The instructions are then decoded and branch prediction is applied to any of the 8 instructions that are branches. The first predicted taken branch is identified and its' address determined. This address is compared to the prefetch address that was sent to the second level cache. If the addresses are not the same, the prefetch is canceled, the correct address is sent to the second level cache and the BTAC is updated with the correct address. If the prefetch address is correct then the prefetch becomes a fetch and a new prefetch is initiated using the BTAC.
[0024] A “basic block” of instructions is next formed starting with the 8 instructions from instruction fetch and may continue with additional sequential instruction fetches of 8 instruction blocks until the end of that basic block is detected. The basic block includes the first and subsequent instructions up to the first branch instruction. If there are no branches then the basic block contains all 8 instructions and the next address would be the sequential address (next address after last instruction). The basic block is added to the trace formation buffer by appending to the end of an existing trace or is used to begin a new trace.
[0025] Once the basic block is moved to the trace buffer, the next set of instructions (fetch or prefetch) are handled in the same way by predicting branches, decoding and using the BTAC to request the next set of instructions.
[0026] Once the trace buffer has been filled with basic blocks (see rules below for determining when full) then the trace line is written into the cache.
[0027] The address of the next instruction (after the last basic block) is also stored in the cache along with the trace line. This address is determined in the normal way of branch prediction/BTAC look-up while determining basic blocks. When the trace line is accessed from the cache, the next trace is known without going through the branch prediction logic. Address flow is represented in FIG. 4 .
[0028] This trace cache is capable of storing trace lines or normal cache lines (instructions in sequential order). Also, for performance reasons, all instructions arriving from the second level cache can be bypassed around the trace cache and dispatched as normal cache lines. Therefore, while building trace lines the instructions are sent onto the dispatch/execute engines to maintain forward progress while generating traces. Trace generation can be terminated whenever it has been determined that the line being built is no longer good for function or performance. A series of rules have been developed for forming traces.
[0029] The set of basic rules governing the building of trace lines (trace generation terminates and a trace is placed in the cache) is listed hereinafter. A system in accordance with this invention may implement one, all or a subset of these rules:
1. Trace lines have a maximum of N instructions (where N may be 16, 24, 32 or some other convenient length). This constraint is due to the physical length of each line in the cache. A basic block that exceeds N instructions in the trace buffer ends the formation of the current trace line. Remaining instructions in the current basic block will be used to start formation of a subsequent trace line. 2. At the end of a basic block, if the trace is filled within L instructions (where L may be 5 or some other convenient length) from the end of the trace buffer, the construction of the trace line will be terminated, and that line is placed in the cache (since it is likely that the next basic block will overflow). This makes traces more useful during subsequent phases of program execution since it potentially avoids a branch within the trace that could end up going in the opposite direction. 3. Traces are terminated on data-dependent branch targets (branch to link, branch to count) since the branch-to address is not accurately predictable. 4. Terminate a trace on a bdnz (and similar type) instruction. These instructions are typically used to form loops, and by terminating a trace at a bdnz, duplication of instructions within the loop is typically avoided. 5. Branches with a negative displacement are assumed to be looping code and will end a trace in order to avoid duplication of instructions within the loop. 6. Trace ends at the end of the Mth basic block. (M may be 4, 5, or some other convenient length). This limits the exposure of branches within a trace altering their behavior with respect to branch-taken direction originally predicted.
[0036] Trace generation is highly dependent upon the branch prediction success rate. In order to make sure that traces are built using “good” branch prediction, it is necessary to wait for the BHT (containing the branch prediction bits) and the BTAC to “warm up”. This process involves running the code in normal cache mode until it has been determined that the branch prediction has warmed up.
[0037] Determination of when the BTAC and BHT are “warmed up” is described in a related patent application filed Oct. 5, 2006 under Ser. No. 11/538,831, entitled “Apparatus and Method for Using Branch Prediction Heuristics for Determination of Trace Formation Readiness”. If the BTAC and BHT are not warmed up, trace formation will not even be attempted. Even after warm up is complete, there are several constraints that branch prediction places on trace formation:
1. Terminate formation of a trace if a BTAC entry is not valid for a branch in the current basic block. If a branch does not have an updated BTAC entry then this is the first time the path has been encountered and there is insufficient knowledge to predict its path. 2. Terminate trace formation on a weakly predicted branch. It is assumed that branch prediction has not been warmed up. The trace may or may not be saved within the trace cache, depending on the position within the trace entry of the weakly predicted branch.
[0040] Traces must be made from basic blocks (code segments) containing the same protection attributes as each other. This is required since the address of code segments is not maintained in the trace cache (only the starting address and the next address at the end). Therefore, the translation process occurs on all code segments when the trace line is built but only on the starting address of the trace line when the trace is accessed from the cache.
1. End trace formation when code has entered into a page with different protection attributes. 2. Instructions: Isync, rfi, sc, mtmsr, trap or ISI will end a trace. 3. These instructions are synchronizing type instructions that change the translation state of the operating system. Therefore the page attributes after the instruction will be different than before.
[0044] FIG. 5 is a flow diagram that illustrates the steps required for trace cache access and forming new entries into the trace cache. The process starts when a given address (AddrA) is presented to the trace cache as a read access. If the access is a HIT (meaning data is resident in the cache) then the data is read out of the cache and the instructions are passed down the pipeline while the next fetch address is used to re-access the trace cache.
[0045] If the cache access is a Miss (meaning data is NOT resident in the cache) then a request is immediately sent to the second level cache for AddrA. AddrA is also used to access the BTAC to obtain the next address to fetch (AddrB). If the BTAC has a valid match for AddrA then AddrB is used to access the trace cache and then sent to the second level cache (if a trace cache miss). If there is not a valid BTAC match for AddrA then AddrB is not known and therefore must wait for AddrA data to compute AddrB.
[0046] Once data arrives from the second level cache for AddrA then the BHT is accessed for branch prediction and the instructions are aligned for adding to the current trace. All branches are then predicted taken/not taken and the next address is determined from the first predicted taken branch. This address is compared against the previous address that was read from the BTAC. If they match then the BTAC is accessed again for the next fetch address. If the addresses do not match then the BTAC entry needs to be corrected and any outstanding second level requests must be canceled.
[0047] Instructions from the second level cache are then bypassed around the trace cache and are also appended to the trace buffer to continue forming the current trace. Once the trace buffer is full (or achieves one of the trace termination criteria) it is written into the trace cache.
[0048] FIG. 6 shows a block diagram of an exemplary design flow 600 used for example, in semiconductor design, manufacturing, and/or test. Design flow 600 may vary depending on the type of IC being designed. For example, a design flow 600 for building an application specific IC (ASIC) may differ from a design flow 600 for designing a standard component. Design structure 620 is preferably an input to a design process 610 and may come from an IP provider, a core developer, or other design company or may be generated by the operator of the design flow, or from other sources. Design structure 620 comprises the circuits described above and shown in FIGS. 1-4 in the form of schematics or HDL, a hardware-description language (e.g., Verilog, VHDL, C, etc.). Design structure 620 may be contained on one or more machine readable medium. For example, design structure 620 may be a text file or a graphical representation of a circuit as described above and shown in FIGS. 1-4 . Design process 610 preferably synthesizes (or translates) the circuits described above and shown in FIGS. 1-4 into a netlist 680 , where netlist 680 is, for example, a list of wires, transistors, logic gates, control circuits, I/O, models, etc. that describes the connections to other elements and circuits in an integrated circuit design and recorded on at least one of machine readable medium. For example, the medium may be a storage medium such as a CD, a compact flash, other flash memory, or a hard-disk drive. The medium may also be a packet of data to be sent via the Internet, or other networking suitable means. The synthesis may be an iterative process in which netlist 680 is resynthesized one or more times depending on design specifications and parameters for the circuit.
[0049] Design process 610 may include using a variety of inputs; for example, inputs from library elements 630 which may house a set of commonly used elements, circuits, and devices, including models, layouts, and symbolic representations, for a given manufacturing technology (e.g., different technology nodes, 32 nm, 45 nm, 90 nm, etc.), design specifications 640 , characterization data 650 , verification data 660 , design rules 670 , and test data files 685 (which may include test patterns and other testing information). Design process 610 may further include, for example, standard circuit design processes such as timing analysis, verification, design rule checking, place and route operations, etc. One of ordinary skill in the art of integrated circuit design can appreciate the extent of possible electronic design automation tools and applications used in design process 610 without deviating from the scope and spirit of the invention. The design structure of the invention is not limited to any specific design flow.
[0050] Design process 610 preferably translates a circuit as described above and shown in FIGS. 1-4 , along with any additional integrated circuit design or data (if applicable), into a second design structure 690 . Design structure 690 resides on a storage medium in a data format used for the exchange of layout data of integrated circuits (e.g. information stored in a GDSII (GDS2), GL1, OASIS, or any other suitable format for storing such design structures). Design structure 690 may comprise information such as, for example, test data files, design content files, manufacturing data, layout parameters, wires, levels of metal, vias, shapes, data for routing through the manufacturing line, and any other data required by a semiconductor manufacturer to produce a circuit as described above and shown in FIGS. 1-4 . Design structure 690 may then proceed to a stage 695 where, for example, design structure 690 : proceeds to tape-out, is released to manufacturing, is released to a mask house, is sent to another design house, is sent back to the customer, etc.
[0051] In the drawings and specifications there has been set forth a preferred embodiment of the invention and, although specific terms are used, the description thus given uses terminology in a generic and descriptive sense only and not for purposes of limitation.
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A design structure embodied in a machine readable storage medium for at least one of designing, manufacturing, and testing a design for a single unified level one instruction cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instructions consistent with conventional cache lines is provided. Instruction branches are predicted taken or not taken using a highly accurate branch history table (BHT). Branches that are predicted not taken are appended to a trace buffer and the next basic block is constructed from the remaining instructions in the fetch buffer. Branches that are predicted taken flush the remaining fetch buffer and the next address is determined using a Branch Target Address Register (BTAC).
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TECHNICAL FIELD
The present invention relates to a novel chewing gum which, when chewed, fights plaque, invigorates the tissue surrounding the necks of the teeth, reduces cavities in teeth, whitens and polishes teeth, and freshens breath. The inventive chewing gum, in a preferred embodiment, comprises a sodium bicarbonate gum base encapsulated with a citric acid coating.
BACKGROUND OF THE INVENTION
Adhesion of oral bacteria to hard surfaces in the oral cavity (restorations, enamel and cement) is one of the main events leading to the development of oral diseases. Adhesion of bacteria to tooth surfaces results in the formation of dental plaque. Dental plaque leads to tooth decay, calculus, gingivitis and periodontitis. Bacterial adherence to dental surfaces can be facilitated by several mechanisms. It is clear that eliminating bacterial deposition on hard surfaces in the oral cavity is a major step in combating oral diseases. The ability of chemical agents to remove plaque is limited. To date, there has been no good alternative to the mechanical removal of plaque through brushing and flossing.
Conventional chewing gum is a mixture of natural or synthetic gums and resins, sweetened with sugar, corn syrup, artificial sweeteners and may also contain coloring agents and flavor. It is a uniquely U.S. product, discovered during the search for rubber materials in the 1860's. The first manufacturing patent for chewing gum was issued in 1869.
The basic raw material for all chewing gum is the natural gum chicle, obtained from the sapodilla tree indigenous to Central America. Because chicle is relatively expensive and often difficult to procure, other natural gums are also used. Recently, synthetic materials such as polyvinylacetate and similar polymers have come into widespread use.
The chewing gum manufacturer melts, washes and filters the crude gum to remove all foreign materials. The gum is then blended with other natural and synthetic resins, waxes and plasticizers, which are added to control the stickiness and chewing characteristics, and the compound is heated, mixed until uniform, cooled and blocked. The blocked gum base is then stored until needed.
The manufacturer of chewing gum starts with a mix of about 22-25% gum base, about 50-60% powdered sugar, about 12-20% corn syrup and about 1-2% color and flavors. This mixture is heated to about 80° C., thoroughly blended, cooled, extruded onto a belt, rolled to proper thickness, then cut, wrapped and packaged. Bubble gum differs from ordinary gum only in that its base is formulated with rubber latex for greater strength.
Sugarcoated gum is made by whirling small cubes of gum in copper pans with sugar syrup, powdered sugar, color and flavor. This mixture builds the colorful, polished, crystallized sugar shell. Sugarless gums are made by substituting sugar alcohols (xylitol, mannitol or sorbitol) for ordinary sugar.
The chewing of gum is very common among both adults and young people. Chewing gum can serve as a drug delivery system, may contain sugar substitutes which are not cariogenic, and may even serve as an anti-bacterial agent. Chewing gum also induces salivary flow which aids in the cleansing of bacteria from the oral cavity. The present invention proposes using a unique form of chewing gum wherein the inventive effervescent gum possesses unique properties that will reduce plaque and freshen the breath.
BACKGROUND ART
Liquid or gel center-filled products, such as Freshen-up Gum (sugar) and Chewels (sugar-free), both manufactured by Warner-Lambert, are currently on the market and are related to the present invention in texture and mouthfeel. However, these gums do not have decay preventive properties, plaque fighting ability or effervescence as found in the present invention. Another product presently on the market is “Yow!” produced by Yow! Laboratories of Fountain Valley, Calif. It is described as a sugar free, bubbling formula that helps reduce plaque and eliminate bad breath. This product is not a chewing gum oral hygiene product.
U.S. Pat. No. 2,470,906 to Taylor discloses a dentifrice containing ascorbic acid and acid analogues of ascorbic acid. The patent describes the use of ascorbic acid to transform mucinous coatings in the oral cavity into easily removable forms. The Taylor dentifrice is also disclosed as containing calcium diphosphate, potassium-aluminum silicate, and flavors. There is no suggestion of a chewing gum dentifrice nor of effervescence.
U.S. Pat. No. No. 3,431,339 to Gyarmathy et al. discloses a chewable dental tablet to be used in conjunction with a toothbrush. The tablet is disclosed as containing a polishing agent, flourine—containing agents, a foaming agent and a waxy releasable matrix.
U.S. Pat. No. 3,962,417 to Howell discloses an effervescent dentifrice in chewable tablet form that is effective against Bacillus acidophilios . The Howell dentifrice tablet was prepared by dry-mixing sodium lauryl sulphate, saccharin, chlorophyllin, magnesium carbonate, citric acid, calcium carbonate, sodium bicarbonate, flavors, magnesium stearate, acacia powder and stannous fluoride. This patent does not disclose nor suggest an oral hygiene chewing gum that comprises a gum stock and a coating containing an edible acid.
U.S. Pat. No. 4,127,645 to Witzel et al. discloses an effervescent tablet that comprises a core portion containing an effervescent couple, and an outer portion which coats or surrounds the core portion. The outer portion is taught to contain a sugar alcohol, such as sorbitol. There is no suggestion of an effervescent chewing gum wherein the base containing gum stock is covered with an acid containing coating.
U.S. Pat. No. 4,169,885 to Raaf et al. discloses a dental hygiene product in the form of a capsule or a filled sweet comprising an outer shell of a hydrophilic substance containing a therapeutic substance such as a fluoride compound and an inner filling material comprising a hydrophobic material such as fats and waxes. This patent teaches that the therapeutic compound is released while the outer shell is dissolved in the mouth. Upon reaching the inner core, the wax or fat coats the teeth thereby retaining the therapeutic in contract with the teeth and gums. This patent makes no mention or suggestion of an effervescent chewing gum.
U.S. Pat. No. 4,563,345 to Arrick discloses a chewing gum having a first phase comprising a chewable material, and a second viscous phase including a fluoride compound.
U.S. Pat. No. 4,753,792 to Aberg discloses a water free, non-oil based, tooth cleaning tablet. The tablet is disclosed as being self-foaming when chewed in the mouth. The tablet is disclosed to comprise less than 50% by weight of a self foaming effervescent couple (i.e. sodium bicarbonate and acid), greater than 35% by weight of an insoluble filling and polishing composition, and an effective amount of a fluoride tooth protecting agent. The Aberg tablet, upon chewing, forms a paste. There is no suggestion of using a chewing gum or separating the effervescent base from the acid.
U.S. Pat. No. 5,380,530 to Hill discloses a therapeutic chewing gum wherein the chewing gum is coated with an emulsion comprising an ingestible surfactant—emulsifier and a polydimethyl siloxane insoluble in said surfactant emulsifier. The coating is taught to contain anti-microbials, stannous fluoride, antioxidants, enzymes, antibiotics, analgesics and others. There is no suggestion in this patent to place an encapsulated edible acid in the coating which surrounds a gum stock that comprises a base, so that upon mastication, an effervescent reaction occurs.
U.S. Pat. No. 5,698,215 to Kalili et al. describes a chewing gum composition with fluoride and citric acid. The patentees propose that their chewing gum utilizes a biochemical reaction which takes place when dental enamel is exposed to citric acid. It is suggested that citric acid opens pores in the dental enamel which allows fluoride to penetrate the prismatic layers of the tooth structure. This patent makes no reference to an effervescent chewing gum wherein the citric acid is encapsulated and is found in the coating portion of the chewing gum piece.
PCT/MX96/00019 patent application (WO97/19668) to Cristiani-Garcia et al. discloses a toothpaste and mouthwash in tablet form which dissolves in the mouth when contacting the saliva. Each tablet is described as containing ascorbic acid 18 mg, sodium bicarbonate 50 mg, tricalcic phosphate 40 mg, sodium laurilsulfate 17 mg, arabic gum 70 mg and natural sweetness and flavoring agents 150 mg. This reference does not disclose nor suggest the use of a chewing gum and further, it fails to suggest that the ascorbic acid be placed in microcapsules and then incorporated into a coating which surrounds a gum stock.
It is thus apparent that a need exists for a sugar-free, effervescent chewing gum that will prevent dental plaque and freshen breath while allowing an inexpensive, convenient method of improving oral hygiene without causing undesired changes of the oral micro flora.
SUMMARY OF THE INVENTION
In general, the present invention is directed to a solid chewable piece of chewing gum comprising:
a) a chewing gum base wherein said base comprises at least one component selected from the group consisting of: alkali metal carbonates, alkali metal bicarbonates, alkaline earth metal carbonates, alkaline earth metal bicarbonates and mixtures thereof; and
b) a coating covering said base wherein said coating comprises at least one edible acid.
The pH of the chewing gum during the initial mastication will be less than about 4.0 to induce salivary flow immediately, and upon further mastication during the stage of effervescence and thereafter the pH is about 7.0 and above. This feature is important as it has been reported that the oral pH should be about 5.5 to counteract the acids produced by bacteria. In one embodiment of the invention the preferred pH of the chewing gum after effervescence is 7.3 and higher. The chewing gum is designed to create an initial blast of tartness that will induce salivary flow. The saliva produced should be retained in the mouth and used like a mouthwash to swish back and forth between the teeth for at least 15 seconds. This action allows the foaming action to penetrate all the crevices of the teeth and gums, loosening food particles and plaque. The user then continues chewing for at least 15 minutes for additional tooth polishing and long lasting breath freshening. The consumers teeth will have a squeaky clean feeling and the tissues of the oral cavity will be invigorated.
In a more preferred embodiment, the piece of chewing gum additionally comprises at least one component selected from sweeteners, therapeutic agents, flavoring ingredients, processing aids, edible oils and breath fresheners. In a further embodiment, the edible acid is encapsulated prior to its inclusion in the coating.
In a more specific embodiment, this invention relates to a sugar-free, effervescent chewing gum comprising:
1) a chewing gum base formulation comprising:
a) sodium bicarbonate;
b) xylitol (a natural sweetener);
c) mannitol (a bulking agent, humectant and sweetener for a cooling sensation);
d) aspartame and acesulfame K (artificial sweeteners);
e) at least one oil selected from the group consisting of: parsley seed oil (a breath freshener), eucalyptus oil (antibacterial), thyme oil (antibacterial), and myrrh oil (gum stimulant);
f) sorbitol (as natural sweetener and bulking agent); and
2) a coating formulation comprising at least one edible acid.
In a more preferred embodiment, the gum base is coated with a coating comprising an edible acid selected from tartaric acid, citric acid, malic acid, ascorbic acid, acid phosphate salts (i.e. monocalcium phosphate) and mixtures thereof. Especially preferred is encapsulated ascorbic acid and citric acid. The coating may also contain TiO 2 as a product whitener.
The effervescent chewing gum, according to the invention, is useful to clean teeth and freshen breath. Further, the novel dental oral hygiene gum utilizes effervescence to enhance a person's ability to prevent gum disease, and polish and whiten teeth.
The oral hygiene gum, according to the invention, is preferably void of agents, such as sweeteners, that would promote tooth decay and/or gum disease. Artificial sweeteners such as aspartame and acesulfame K are preferred. The oral hygiene gum may also contain natural and/or artificial flavors, with natural flavors being preferred. The gum, according to the invention, may also include coloring agents (in addition to the TiO 2 or in place of), however, the use of coloring agents is not preferred.
The presence of a base compound in the core gum stock is required. The useful bases include calcium carbonate and sodium bicarbonate. The use of sodium bicarbonate and calcium carbonate is especially preferred as this combination possesses the added feature of being a “tooth polisher” in addition to providing part of the “foaming” component.
The effervescence system (i.e. sodium bicarbonate and citric acid) of the inventive chewing gum comprises from 10 to 50% by weight of the final product. More preferably the effervescence system comprises 10-40% by weight of the final product, with 20-35% by weight being most preferred. Further, the weight ratio of acid to base can range from 0.5 to 2.0 with 0.6 to 1.0 being more preferred and 0.7 to 0.8 being most preferred. This ratio of acid to base is important as the final pH of the chewing gum at the end of mastication should be as high as possible.
There if further disclosed an effervescent solid piece of chewing gum comprising by weight:
a) 25-35% gum base;
b) 30-40% of at least one compound selected from Xylitol, mannitol and sorbitol;
c) 2-10% glycerin;
d) 0.1-0.5% of at least one oil selected from peppermint, menthol, eucalyptus, parsley, thyme and myrrh;
e) 0.2-0.5% of at least one artificial sweetener;
f) 0.5-1.0% lecithin;
g) 2.0-10% calcium carbonate;
h) 5.0-15% sodium bicarbonate; and
i) 5.0-15% of at least one edible acid.
DETAILED DESCRIPTION OF THE INVENTION
One of the major problems associated with the production of an effervescent oral hygiene chewing gum is shelf life. Those skilled in the art will readily appreciate that the organic acids and bases used to generate the effervescent must be kept separate before the time effervescence is desired. While the presence of a liquid, such as water, is required before the reaction will occur, even small levels of moisture found in chewing gum will allow for the reaction to take place over time. With desired shelf-lives of more than one year, an effervescent chewing gum must be stable, while promptly evidencing effervescence once placed in the mouth and chewed. The production of a strong and stable effervescent chewing gum is one aspect of the invention.
In the production of long-shelf lived effervescent chewing gum pieces for oral hygiene in accordance with this invention, the basic components, which are the alkali metal carbonates and/or bicarbonates are dispersed within the chewing gum base which also includes aromatic oils, sweeteners, whiteners and therapeutic agents, to result in a gum stock. The edible acids, such as tartaric, citric, ascorbic, malic, acid phosphate salts or mixtures thereof are found in the coating surrounding the gum stock. The edible acids are preferably encapsulated to prevent their reaction with the carbonates and/or bicarbonates that are present in the base formulation. The coating may also include flavoring agents, sweeteners, therapeutic agents, and coloring agents. Once placed in the mouth, mastication initially dissolves the coating, releasing the acid which promotes further salivation and upon further mastication of the chewing gum piece the reaction (generation of CO 2 ) between the base and the acid begins, thus producing a vigorous effervescence. This vigorous effervescence in combination with the chewing and the various therapeutic agents (i.e. whiteners and breath fresheners) results in a pleasing hygienic experience for the consumer.
The chewing gum piece is designed so that the effervescence continues for at least 1 minutes, more preferably at least 3 minutes, and most preferably at least 5 minutes. It should be noted that the effervescent chewing gum, according to the invention, does not preclude the presence of fluoride. However, it is the inventors' belief that fluoride compounds need not be present in the inventive chewing gum since other fluoride sources such as commercially available toothpaste and fluoridated drinking water provide adequate levels to the consumer. Further, the effervescent chewing gum, according to the invention, is not intended to replace good tooth brushing habits and proper oral hygiene. The purpose of the inventive chewing gum is to supplement a total program of dental care. Prevention is the key to total dental care and visits to a dentist are an important part of the prevention process.
In general, known techniques can be used to produce the chewing gum with plaque fighting capabilities in accordance with the invention. One aspect of this invention resides in the discovery that the sodium bicarbonate gum base coupled with edible acid encapsulation in the coating provides a highly acceptable, non-toxic chewing gum that does not interfere with other oral hygiene regimes. Furthermore, use of such an anti-plaque chewing gum does not eradicate the beneficial bacteria in the oral cavity, thus minimizing undesired changes in the oral microflora.
Experimental
In actual use, the sugarless gum of the present invention would be used by both adults and children as it is a convenient, low cost method of maintaining oral hygiene. The present invention may be better understood in view of the following examples which are illustrative only and should not be construed as limiting the invention.
Preliminary experiments were performed in the development of this invention which were directed to physically admixing various compounds to determine the most effective combinations.
Five (5) experiments were conducted.
1) the Control;
2) Experimental No. 1—the Control plus Essential Oils (parsley seed, myrrh, eucalyptus, and thyme);
3) Experimental No. 2—the mixture of #2 combined with calcium carbonate and a two fold increase in the oil concentration;
4) Experimental No. 3—the mixture of #3 plus sodium carbonate, coated with citric acid (to simulate a pan coated gum); and
5) Experimental No. 4—the mixture of #3 plus sodium bicarbonate mixed in with citric acid.
The Control served as a baseline for evaluating the gum mixing process and the oral hygiene ingredient variables. The oral hygiene formulations were developed taking into account the desired product indications and the intended use attributes (i.e. final pH).
General Process Conditions
The process to prepare the base gum stock included placing the lecithin and the gum base in a heated blender (5 liter Stephan mixer) and the gum base was softened to about 60° C. Dry blending of 95% of the mannitol, sorbitol and xylitol was conducted to prepare Dry Blend No. 1. Dry blending of the aspartame, acesulfame K and flavor enhancers together with the remaining 5% portion of the mannitol, sorbitol and xylitol was conducted to prepare Dry Blend No. 2.
Dry Blend No. 1 was then added to the gum base/lecithin mixture in the Stephan mixer. Mixing continued until the mass was homogeneous. The glycerin and maltitol syrup was then added and mixing continued until homogeneous (about 5 minutes). Dry Blend No. 2 was then added with mixing, followed by flavor oil. Mixing was continued until a homogeneous mass resulted. This is the Control Base Stock. To the Control Base Stock was added the various active ingredients set forth below to prepare Experimental Nos. 1-4.
EXAMPLE I
The following Table 1 lists the compounds and amounts that were mixed in a 5 liter Stephan mixer to prepare the Control product. The ingredients listed in the following Tables were obtained from the following manufacturers:
Gum Base—Cafosa Gum S/A of Madrid, Spain, Prestige PL gum base.
Xylitol Powder—Cultor Food Science of Ardsley, N.Y., CM90 crystalline xylitol.
Mannitol Powder—Roquette, Inc. of Keokuk, Iowa.
Sorbitol Powder—Roquette, Inc. of Keokuk, Iowa, Neosorb P60W sorbitol FCC.
Glycerin—Vitusa Products, Inc. of Berkley Heights, N.J., kosher glycerin USP.
Peppermint/Menthol Flavor Oil—Givaudan Roure, Inc. of Clifton, N.J.
Flavor Enhancer—Flavor and Fragrance Spec. of Mahwak, N.J.
Acesulfame K—Nutrinova, Inc. of Somerset, N.J.
Aspartame—Monsanto of St. Louis, Mo.
Lecithin—Central Soya of Fort Wayne, In. Centrophill K lecithin.
Calcium Carbonate—Watson Foods Co., Inc. of West Haven, Conn., FCC, 1-40 micron.
Sodium bicarbonate—Rhône-Poulenc, Inc. of Cranberry, N.J.
Citric acid (encapsulated)—Balchem, Inc. of Slate Hill, N.Y., 85% citric acid, FCC, USP;
Eucalyptus, Parsley, Thyme and Myrrh Oils—Frutarom Meer Corp. of North Bergen, N.J.
TABLE 1
Control
% by wt. of
Batch Quantity
Formulation
Ingredient
gms
30.000%
Gum Base
450.000
15.000%
Xylitol Powder
225.000
5.000%
Mannitol Powder
75.000
5.000%
85% Maltitol Syrup
75.000
38.225%
Sorbitol Powder
573.375
5.000%
Glycerin
75.000
0.750%
Peppermint/
11.250
Menthol Flavor Oil
0.075%
Flavor Enhancer
1.125
0.100%
Aspartame
1.500
0.100%
Acesulfame Potassium
1.500
0.750%
Lecithin
11.250
0.000%
Calcium Carbonate
0.000
(1-40 microns)
0.000%
Sodium bicarbonate
0.00
0.000%
Citric Acid
0.00
(encapsulated)
0.000%
Eucalyptus Essential Oil
0.000
0.000%
Parsley Seed Essential
0.00
Oil
0.000%
Thyme Essential Oil
0.000
0.000%
Myrrh Essential Oil
0.00
The 1500 gms of the resulting gum product produced was divided in pieces of about 3.5 gms each. A sensory evaluation of the gum produced in this example (control) indicated that it had good sweetness, flavor and generally a pleasing mouthfeel. The use of xylitol, a sugar alcohol, is preferred as it is sweet, not absorbed through the intestine and does not promote tooth decay.
EXAMPLE II
The following Table 2 lists the ingredients and amounts mixed in a 5 liter Stephan mixer to prepare Experimental No. 1.
TABLE 2
Experimental No. 1
Control Plus Essential Oils
Batch Quantity
% of Formulation
Ingredient
gms
30.000%
Gum Base
450.000
15.000%
Xylitol Powder
225.000
5.000%
Mannitol Powder
75.000
5.000%
85% Maltitol Syrup
75.000
38.151%
Sorbitol Powder
572.265
5.000%
Glycerin
75.000
0.750%
Peppermint/
11.250
Menthol Flavor Oil
0.075%
Flavor Enhancer
1.125
0.100%
Aspartame
1.500
0.100%
Acesulfame K
1.500
0.750%
Lecithin
11.250
0.000%
Calcium carbonate
0.000
(1-40 microns)
0.000%
Sodium bicarbonate
0.00
Powder
0.000%
Citric Acid
0.00
(encapsulated)
0.020%
Eucalyptus Oil
0.300
0.20%
Parsley Seed Oil
0.300
0.017%
Thyme Oil
0.255
0.17%
Myrrh Oil
0.255
In this experiment the amount of sorbitol powder was decreased over the Control (Example I) and the essential oils, eucalyptus and thyme were increased while the essential oils myrrh and parsley were added. These changes were found to enhance the aromatic sensory characteristics of this product.
EXAMPLE III
The following Table 3 lists the compounds and amounts mixed in a 5 liter Stephan mixer to produce Experimental No. 2. The 1.5 kg batch was divided in 3.5 gm pieces after production and subjected to sensory evaluation.
TABLE 3
Experimental No. 2
Control Plus Increased Essential Oils Plus Calcium Carbonate and a
Two Fold Increase in Essential Oil Concentrations
Batch Quantity
% of Formulation
Ingredient
gms
30.000%
Gum Base
450.000
15.000%
Xylitol Powder
225.000
5.000%
Mannitol Powder
75.000
5.000%
85% Maltitol Syrup
75.000
33.097%
Sorbitol Powder
496.455
5.000%
Glycerin
75.000
0.750%
Peppermint/
11.250
Menthol Flavor Oil.
0.075%
Flavor Enhancer
1.125
0.100%
Aspartame
1.500
0.100%
Acesulfame K
1.500
0.750%
Lecithin
11.250
5.000%
Calcium carbonate
75.000
(1-40 microns)
0.000%
Sodium bicarbonate
0.00
Powder
0.000%
Citric Acid
0.00
(encapsulated)
0.040%
Eucalyptus Oil
0.600
0.020%
Parsley Seed Oil
0.300
0.034%
Thyme Oil
0.510
0.034%
Myrrh Oil
0.510
The product of this experiment was evaluated for organoleptic properties and was found adequate in sweetness. The increase in the calcium carbonate content had little effect on mouthfeel and taste. The essential oils, eucalyptus, thyme and myrrh were increased to further enhance the aromatic sensory characteristics of this product.
EXAMPLE IV
In this experiment the base gum stock (all components listed in Table 4 except the encapsulated citric acid) was prepared, rolled and cut into about 3.5 gm pieces. Each piece was then rolled in the encapsulated citric acid. This technique is known in the confection industry as “sanding”.
TABLE 4
Experimental No. 3
Control Plus Increased Essential Oils Plus Calcium Carbonate and a
Two Fold Increase in Essential Oil Concentrations Plus
Sodium Bicarbonate Coated with Encapsulated Citric Acid
in a Simulated Pan Coating
Batch Quantity
% of Formulation
Ingredient
gms
30.000%
Gum Base
450.000
15.000%
Xylitol Powder
225.000
5.000%
Mannitol Powder
75.000
5.000%
85% Maltitol Syrup
75.000
13.097%
Sorbitol Powder
170.45
5.000%
Glycerin
75.000
0.750%
Peppermint/
11.250
Menthol Flavor Oil
0.075%
Flavor Enhancer
1.125
0.100%
Aspartame
1.500
0.100%
Acesulfame K
1.500
0.750%
Lecithin
11.250
5.000%
Calcium carbonate
75.000
(1-40 microns)
11.364%
Sodium bicarbonate
170.45
Powder
8.636%
Citric Acid
129.55
(encapsulated)
(sanded)
0.040%
Eucalyptus Oil
0.600
0.020%
Parsley Seed Oil
0.300
0.034%
Thyme Oil
0.510
0.034%
Myrrh Oil
0.510
The sensory tests indicated that the chewing gum effervested upon mastication, produced a pleasing sensation and taste, and left the teeth and gingiva feeling clean and stimulated.
EXAMPLE V
The following Table 5 lists the compounds and amounts mixed in a 5 liter Stephan mixer to produce Experimental No. 4.
TABLE 5
Experimental No. 4
Control Plus Increased Essential Oils Plus Calcium Carbonate and a
Two Fold Increase in Essential Oil Concentrations Plus
Sodium Bicarbonate Mixed with Encapsulated Citric Acid
Batch Quantity
% of Formulation
Ingredient
gms
30.000%
Gum Base
450.000
15.000%
Xylitol Powder
225.000
5.000%
Mannitol Powder
75.000
5.000%
85% Maltitol Syrup
75.000
13.097%
Sorbitol Powder
196.455
5.000%
Glycerin
75.000
0.750%
Peppermint/
11.250
Menthol Flavor Oil
0.075%
Flavor Enhancer
1.125
0.100%
Aspartame
1.500
0.100%
Acesulfame K
1.500
0.750%
Lecithin
11.250
5.000%
Calcium carbonate
75.000
(1-40 microns)
11.364%
Sodium bicarbonate
170.45
Powder
8.636%
Citric Acid
129.55
(encapsulated)
(mixed in)
0.040%
Eucalyptus Oil
0.600
0.020%
Parsley Seed Oil
0.300
0.034%
Thyme Oil
0.510
0.034%
Myrrh Oil
0.510
From a taste testing panel it was determined that this formulation was not as tart as the product produced in Example 4, and that the flavor and essential oil levels should be increased. It was also determined that the effervescence, upon mastication, was not as prolonged when compared to Experimental No. 3. The effervescence reaction actually began to occur during processing in this experiment. This was considered unacceptable as this product would have no shelf-life. This Experiment demonstrated to the inventors that the acid component of the effervescent couple should be an outside coating of the base containing gum base stock. The results from these experiments demonstrate that a convenient and low cost chewing gum can be produced that has favorable organoleptic properties and a refreshing effervescent character.
EXAMPLE VI
From the information and experience gained in Examples I-V the inventors conducted a 3 kg. pilot scale production run of the inventive chewing gum formulation. Table 6 sets forth the list of ingredients, the percent of formulation and the quantity of each ingredient.
TABLE 6
Batch Quantity
% of Formulation
Ingredient
gms
30.000%
Gum Base
900
15.000%
Xylitol Powder
450
5.000%
Mannitol Powder
150
15.534%
Sorbitol Powder
466.02
5.000%
Glycerin
150
1.5%
Peppermint/
45
Menthol Flavor Oil
0.15%
Flavor Enhancer
4.5
0.100%
Aspartame
3.0
0.100%
Acesulfame K
3.0
0.750%
Lecithin
22.5
(soy bean)
1.666%
Encapsulating
49.98
Material from
Citric Acid
5.000%
Calcium carbonate
150
(1-40 microns)
10.559%
Sodium bicarbonate
316.77
Powder
11.107%
Citric Acid
283.23
(encapsulated)
0.060%
Eucalyptus Oil
1.8
0.020%
Parsley Seed Oil
0.6
0.064%
Thyme Oil
1.8
0.06%
Myrrh Oil
1.8
Total batch size was 3.0 kg.
The gum base formulation was prepared by first dry blending the xylitol, mannitol and sorbitol to produce Dry Blend No. 1. The aspartame, acesulfame K, flavor enhancer and 5% of Dry Blend No. 1 were dry blended to prepare Dry Blend No. 2. The calcium carbonate and the sodium bicarbonate were dry blended to prepare Dry Blend No. 3. To a mixer (Sigma Blade ) at 135° F. was added the gum base and the lecithin. Then one third of Dry Blend No. 1 was added to the mixer and mixing continued for about 2 minutes. Then about one third of Dry Blend No. 1 was added with all of Dry Blend No. 2 and mixing continued for about 3 minutes, after which the remaining third of Dry Blend No. 1 was added and mixing continued for about 3 minutes. About one half of Dry Blend No. 3 was added and after about 2 minutes of mixing one half of the glycerin was added and the remaining one half of Dry Blend No. 3. After about 3 minutes of mixing the remaining one half of the glycerin was added and mixing continued for another 3 minutes, after which all of the oils were added and mixing continued for about 2 minutes. The product was then dumped onto wax paper and rolled into sheets. After cooling, the gum base formulation was cut into 1.5 gm pieces and tempered overnight prior to coating.
The coating containing the edible acid was applied to the gum base formulation pieces through the use of a Pan Coating machine. The gum pieces were added to the Pan and 10 gms of a 25% total solids solution of gum arabic in water was then slowly added to thoroughly wet the pieces. 88.28 gms of sorbitol powder was then added slowly as the gum pieces sweat back moisture. More gum arabic solution was added as the pieces became too dry to pick up more sorbitol. After addition of all the sorbitol, the pieces were tumbled until dry. A powder mixture of 34.33 gms of sorbitol and 111.07 gms of the encapsulated citric acid was then prepared. After re-wetting the pieces with the gum arabic solution, the sorbitol/citric acid powder was slowly added. A final hard coat was then added which consisted of 74.11 gms of 70% total solid solution of sorbitol and 8.00 gms of TiO 2 .
EXAMPLE VII
Using the procedure described in Example VI, yet another effervescent chewing gum according to the invention was prepared. The amount of each ingredient used is set forth in Table 7.
TABLE 7
Batch Quantity
% of Formulation
Ingredient
gms
30.000%
Gum Base
900
15.000%
Xylitol Powder
450
5.000%
Mannitol Powder
150
0.15%
Powdered Mint
4.5
Flavor
15.114%
Sorbitol Powder
453.42
5.000%
Glycerin
150
1.5%
Peppermint/
45
Menthol Flavor Oil
0.3%
Flavor Enhancer
9.0
0.32%
Acesulfame K
9.6
0.750%
Lecithin
22.5
(soy bean)
1.666%
Encapsulating
49.98
Material
5.000%
Calcium carbonate
150
(1-40 microns)
10.559%
Sodium bicarbonate
316.77
Powder
11.107%
Citric Acid
283.23
(encapsulated)
0.060%
Eucalyptus Oil
1.8
0.020%
Parsley Seed Oil
0.6
0.06%
Thyme Oil
1.8
0.06%
Myrrh Oil
1.8
In a manner similar to that described in Example VI the gum pieces were prepared and the coating was applied. In this formulation the sweetness and flavor intensity were increased over the formulation of Example VI.
EXAMPLE VIII
In an effort to increase the effervescence, yet another chewing gum according to the invention was prepared in this Example. The listing of ingredients is set forth in Table 8.
TABLE 8
Batch Quantity
% of Formulation
Ingredient
gms
30.000%
Gum Base
900
15.000%
Xylitol Powder
450
5.000%
Mannitol Powder
150
0.150%
Powdered Mint
4.5
Flavor
15.114%
Sorbitol Powder
453.42
5.000%
Glycerin
150
1.5%
Peppermint/
45
Menthol Flavor Oil
0.3%
Flavor Enhancer
9.0
0.32%
Acesulfame K
9.6
0.750%
Lecithin
22.5
(soy bean)
1.666%
Encapsulating
49.98
Material
5.000%
Calcium carbonate
150
(1-40 microns)
10.559%
Sodium bicarbonate
316.77
Powder
11.107%
Citric Acid
283.23
(encapsulated)
0.060%
Eucalyptus Oil
1.8
0.020%
Parsley Seed Oil
0.6
0.06%
Thyme Oil
1.8
0.06%
Myrrh Oil
1.8
EXAMPLE IX
A consumer panel was organized and evaluated the oral maintenance chewing gums prepared in Examples VI-VIII. The panel was requested to rank the following: tartness, foaming/effervescence, long lasting flavor, chewing properties, and overall mouthful. Characteristics were reported as Very Bad, Bad, OK, Good and Very Good using a scale of 1 for Very Bad and 5 for Very Good.
The results of this sensory panel are shown in Table 9.
TABLE 9
Sensory Evaluation *
Exp. VI
Exp. VII
Exp. VIII
n = 19
n = 31
n = 26
Tartness
2.58
2.81
2.35
Foaming/Effervescence
4.00
3.40
3.54
Long Lasting Flavor
3.21
3.52
3.52
Chewing Properties
3.74
4.03
3.69
Overall Mouthfeel
3.42
3.90
3.62
Product Claims**
3.76
3.69
3.84
* reported as average of value from consumer
**initial blast of tartness to induce salivary flow, effervescence, long lasting cool minty flavor to freshen breath
As set forth in Table 9 the consumers overall found the chewing gums according to the invention to provide a pleasant experience. In general the chewing gum produced in Example VII was favored over the gums produced in Examples VI and VIII.
EXAMPLE X
pH of Gum
To test the changing pH of Experimental No. VII one piece of the gum produced in Example VII was ground and diluted (50%) with dionized water. The initial pH registered 3.62 then the pH slowly climbed over a period of 2.5 hours to final stabilized pH of 7.82. Of course the pH change in the mouth of a human would be much more rapid as the chewing would facilitate the mixing of the ingredients.
EXAMPLE XI
pH of Gum
An 8.3 gm sample of the chewing gum produced in Example VIII was diluted with distilled water (1:1). The sample was stirred and the pH checked at 15 minute intervals. The initial pH at 25° C. was 3.49. The pH steadily increased over a five hour period while dissolving. The final pH was 7.64.
From Examples X and XI it is evident that the chewing gums according to the invention perform as designed, that is, the product is initially acidic but eventually becomes basic. This is a function of the acid to base ratio. The chewing gums according to the invention will provide a final pH of 6.0 or above to help neutralize the acids generated by byproducts of the fermentation of food particles by oral bacteria. It is these acids that lead to the development of plaque.
Industrial Applicability
Adhesion of oral bacteria to surfaces in the oral cavity is one of the main events leading to oral diseases and halitosis. The formation of dental plaque leads to tooth decay, calculus and gingivitis. Mechanical removal (i.e. brushing and flossing) of the plaque is still the best method and the chewing gum, according to this invention, is designed to promote plaque removal and reduce the adhesion of oral bacteria to the oral cavity. As chewing gum is popular among adults and young people, the product, according to this invention, would benefit the overall population in reducing oral disease. The inventive chewing gum with its unique combination of an edible acid in the coating, which stimulates the salivary glands, and effervescent properties combined with selected flavor oils, polishing and whitening agents, results in a unique experience. In a preferred embodiment of the invention, the chewing gum is sugar free and utilizes xylitol as a sweetening agent. Xylitol does not promote tooth decay. Thus, the chewing gum, according to the invention, will thus reduce plaque and freshen the breath without side effects (i.e. change in beneficial oral microflora). The chewing gum in a preferred embodiment not only provides a pleasing effervescence but also good flavor, texture and mouthfeel without offensive abrasiveness.
While the formula and method of making said effervescent chewing gum disclosed herein constitute a preferred embodiment of this invention, it is to be understood that the invention is not limited to this precise formulation or method and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.
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Disclosed is an oral hygiene preparation which is plaque disrupting in the form of a chewing gum. The chewing gum comprises a core containing a carbonate and/or bicarbonate which is surrounded by a coating that contains an encapsulated edible acid. Upon mastication the chewing gum effervesces, thus promoting the cleansing and breath freshening properties of the preparation.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of the filing date of U.S. Provisional Application Ser. No. 60/375,560, filed Apr. 25, 2002.
FIELD OF THE INVENTION
The present invention relates to providing a supply of ozone.
BACKGROUND
Ozone is widely utilized for processes such as drinking water disinfection, and control of gaseous pollutants such as NO x . However, for large systems, the cost of operating ozone production plants becomes a very large part of the overall system cost. Therefore, various methods for reducing the cost of producing ozone have been implemented. For example, in ozone production plants, ozone-depleted oxygen has been recycled to ozone generators and waste gas from oxygen generators has been used to purge ozone during the pressure swing adsorption process. However, there is need for additional improvements to ozone production plants to reduce the overall system cost of operating production plants used for processes such as drinking water disinfection, waste water treatment, and control of gaseous pollutants such as NO x .
SUMMARY
There is provided, a method of providing ozone at a selected pressure above atmospheric pressure comprising:
supplying a purge gas supply pressurized above the selected pressure to at least one ozone adsorption apparatus;
desorbing ozone from said ozone adsorption apparatus with said pressurized purge gas supply; and
delivering a mixture of said ozone and said purge gas supply at the selected pressure without further compression.
In one embodiment, there is provided a method of providing ozone at a selected pressure above atmospheric pressure comprising:
providing a supply of compressed dry air at a pressure above the selected pressure;
diverting a first portion of said compressed dry air supply to an oxygen generator;
generating an oxygen supply with said oxygen generator;
directing said oxygen supply to an ozone generator;
generating an ozone-rich oxygen supply with said ozone generator;
passing said ozone-rich oxygen supply through at least one pressure swing adsorption tower;
adsorbing ozone from said ozone-rich oxygen supply in said pressure swing adsorption tower, to provide an ozone-depleted oxygen supply;
recycling the ozone-depleted oxygen supply to said ozone generator;
diverting a second portion of said compressed dry air supply to said pressure swing adsorption tower;
desorbing said ozone from said pressure swing adsorption tower using said second portion of said compressed dry air supply; and
delivering a mixture of said ozone from said pressure swing adsorption tower and said second portion of said compressed air supply at the selected pressure without further compression.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of ozone production plant having an oxygen generator using nitrogen adsorption beds to generate an oxygen supply and dryer beds to generate a compressed dry air supply.
FIG. 2 is a schematic representation of ozone production plant having an oxygen generator using a cryogenic oxygen generator to generate an oxygen supply and a dry nitrogen supply.
FIG. 3 is a schematic representation of ozone production plant having an oxygen generator using a cryogenic oxygen generator to generate a dry oxygen supply and a compressed dry air supply.
FIG. 4 is a schematic representation of a vaporized liquid oxygen supply for the oxygen purge and pressurization cycles and for compressing the ozone-depleted oxygen supply.
FIG. 5 is a schematic representation of a two tower pressure swing adsorption plant.
FIG. 6 is a schematic representation of an improvement to the two tower pressure swing adsorption plant.
FIG. 7 is a graph showing the experimental results of ozone adsorption-desorption using dry nitrogen during the waste gas purge cycle.
FIG. 8 is a graph showing the experimental results of ozone adsorption-desorption using wet nitrogen during the waste gas purge cycle.
DETAILED DESCRIPTION
A method is provided wherein the operation of ozone production plants are improved. In certain embodiments, the need for additional compression before utilization of a supply mixture of a waste gas and ozone is eliminated. In certain embodiments, various cryogenic oxygen generators, particularly suitable for generating oxygen for use in large ozone use processes may be used. A vaporized liquid oxygen supply may be used to simplify the recycling of an ozone-depleted oxygen supply to the ozone generator. A high purity oxygen supply, rather than the ozone-depleted oxygen supply, may be used during the oxygen purge and pressurization cycles of a pressure swing adsorption process to minimize the build up of inerts such as nitrogen during oxygen recycle. The size of an ozone buffer tank used to reduce pressure fluctuations and concentration fluctuations of ozone may also be reduced. The waste gas supply used during the waste gas purge cycle may be warmed to allow for use of higher pressures during the waste gas purge cycle than afforded during the ozone adsorption cycle. The waste gas supply may remain wet during the waste gas purge cycle to eliminate the need for drying a compressed air supply before use for ozone desorption, and allowing use of adsorbents with higher ozone adsorption capacity.
As shown in the accompanying Figures, a plant for the production of ozone is generally indicated by the numeral 10 . In certain of the embodiments of this invention, the ozone production plant 10 has an ozone generator 11 and a two tower pressure swing adsorption (PSA) apparatus or plant 12 . The first tower 13 and second tower 14 of the two tower PSA plant 12 each have an adsorption bed (not shown) used for the adsorption and desorption cycles. These adsorption beds may contain adsorbents such as silica gel, high silica mordenites, dealuminated Y zeolite, and other materials that do not destroy a significant amount of ozone. Adsorbents other than silica gel may require some moisture on them to keep ozone destruction below acceptable levels. These adsorbents adsorb and desorb ozone during the process of ozone generation performed by the ozone generation plant 10 described hereinbelow. Furthermore, even though two towers with their adsorption beds are typical for ozone production, additional towers and their corresponding adsorption beds would allow for a more continuous operation of the ozone production plant 10 .
The adsorption beds of the first tower 13 and second tower 14 pass through pressurization, ozone adsorption, waste gas purge (also called ozone desorption and regeneration), and oxygen purge cycles. The two tower PSA plant 12 of FIGS. 1-3 are each configured to facilitate these cycles. For example, the two tower PSA plant 12 is provided with a first switching system 17 and second switching system 18 . These switching systems contain various valves that operate to connect and disconnect the first tower 13 or second tower 14 to different gas supplies. The intermittent connection and disconnection of different gas supplies allows the first tower 13 and second tower 14 to operate out of phase with one another. Such a phase difference allows the two tower PSA plant 12 to operate relatively continuously.
For illustrative purposes, but not by way of limitation, the general operation of the ozone production plant 10 as shown in FIGS. 1-3 will be described. An oxygen supply 15 is provided to the ozone generator 11 . The ozone generator 11 operates to provide an ozone-rich oxygen supply 16 to the first switching system 17 . The ozone-rich oxygen supply 16 is directed by the first switching system 17 to the two tower PSA plant 12 .
The first tower 13 and second tower 14 both utilize the ozone-rich oxygen supply 16 , and may operate according to the same pressure swing adsorption process. However, the phase difference between either tower dictates that neither are in the same mode of operation at any given time. For example, at a given time, the adsorption bed of the first tower 13 could be undergoing the adsorption cycle, and the adsorption bed of the second tower 14 could be undergoing the waste gas purge cycle. The total time of one cycle of the pressure swing adsorption cycle may range from about 2 to about 30 minutes. For simplicity, the general operation of the first tower 13 is further described below.
To initiate the operation of the first tower 13 , the first switching system 17 directs the ozone-rich oxygen supply 16 to the first tower 13 where it is used during the adsorption cycle. The ozone-rich oxygen supply 16 may have a pressure ranging from about 5 to about 50 psig, and the adsorption cycle may be performed at a temperature range from about −50° C. to about 50° C. During the adsorption cycle, the ozone from the ozone-rich oxygen supply 16 is adsorbed by the adsorption beds of the first tower 13 . Part of the ozone-depleted oxygen supply 20 is directed by the second switching system 18 to the second tower 14 (for use in the pressure swing adsorption process occurring in the second tower 14 ) and the remainder is directed to the blower 21 . The blower 21 may return a portion of the ozone-depleted oxygen supply 20 to the ozone generator 11 to be recycled.
During the waste gas purge cycle, the ozone adsorbed from the ozone-rich oxygen supply 16 is desorbed from the adsorption beds by a waste (or purge) gas supply 22 (such as either a compressed dry air supply 34 , 52 or a nitrogen supply 44 ). The waste gas supply 22 may have a pressure ranging from about 1 to about 30 psig, and the waste gas purge cycle is performed at a temperature range from about −50° C. to about 100° C. The pressure of waste gas supply 22 is typically lower than the oxygen supply 15 entering the ozone generator, but can be adjusted depending on the needs of the application. Furthermore, the mass flow rate of the waste gas supply 22 can be higher or lower than the ozone-rich oxygen supply 16 , however, the relative flow rates must be sufficient to obtain steady state operation of the pressure swing adsorption process. As will be discussed hereinbelow, the waste gas supply 22 may be generated by the oxygen generation apparatus 23 , 39 , and 49 , and may be provided to the first tower 13 by the second switching system 18 . The waste gas supply 22 purges the ozone from the first tower 13 , and the resulting supply mixture 24 of waste gas and ozone is subsequently directed via the first switching system 17 to the ozone utilization applications, for example, a drinking water disinfection system.
During the oxygen purge and pressurization cycles, the ozone-depleted oxygen supply 20 from the second tower 14 may be directed by the second switching means 18 to the first tower 13 . The first tower 13 may be sequentially purged of any excess waste gas supply 22 and pressurized using the ozone-depleted oxygen supply 20 . The pressure swing adsorption cycle is subsequently repeated in the first tower 13 . Furthermore, the pressure swing adsorption process continues in both the first tower 13 and the second tower 14 during the ozone generation process.
As discussed above, the supply mixture 24 of waste gas and ozone may be directed to drinking water disinfection systems (purification), waste water treatment systems, or NO x abatement systems. Such drinking water disinfection systems and waste water treatment systems require the supply mixture 24 to be provided at pressures of about 10 to about 25 psig. NO x abatement systems require ozone supply pressures between 10 and 15 psig. However, additional compression of the supply mixture 24 after exiting the first tower 13 and second tower 14 would require a compressor and the power associated with it, and would lead to loss of ozone. This would be the case if the waste gas from the nitrogen adsorbing beds 30 and 31 in FIG. 1 , rather than the compressed dry air supply 34 , were used as the waste gas supply 22 for the waste gas purge cycle. In this case, the waste gas from the nitrogen adsorbing beds 30 and 31 would be at close to atmospheric pressure and the supply mixture 24 would be at close to atmospheric pressure and would require compression. The ozone production and methods described above eliminate the need for additional compression of the supply mixture 24 , as discussed further below.
In the ozone production plant 10 , various oxygen generators 23 , 39 , and 49 can be used to produce the oxygen supply 15 and the waste gas supply 22 . In each of the embodiments of the oxygen generators 23 , 39 , and 49 shown in FIGS. 1-3 , the waste gas supply 22 supplied to the first tower 13 and second tower 14 during the waste gas purge cycle discussed above, is provided at an elevated pressure, sufficient to provide the supply mixture 24 at the desired selected pressure, taking into account the known pressure drops throughout the system. For example, a compressed air supply 32 is initially compressed to the required pressure by a compressor 33 . The compressed air supply 32 is delivered to the oxygen generators 23 where the oxygen supply 15 and waste gas supply 22 are produced. The waste gas supply 22 is directed to the first tower 13 and second tower 14 , and additional compression is unnecessary because of the initial compression by the compressor 33 .
Even though each of the oxygen generators 23 , 39 , and 49 respectively depicted in FIGS. 1-3 eliminate the need for additional compression of the waste gas supply 22 , these oxygen generators operate differently. For example, FIG. 1 depicts an oxygen generator 23 using pressure or vacuum swing adsorption (PSA or VSA) to generate the oxygen supply 15 . The oxygen generator 23 is divided into dryer beds 28 and 29 and nitrogen adsorbing beds 30 and 31 . The dryer beds 28 and 29 remove moisture from the compressed air supply 32 . After exiting the dryer beds 28 and 29 , the resulting compressed dry air supply 34 is divided. One part becomes the waste gas supply 22 , and the other part is directed to the nitrogen adsorbing beds 30 and 31 . The nitrogen adsorbing beds 30 and 31 adsorb nitrogen from the compressed dry air supply 34 to produce the oxygen supply 15 .
FIG. 2 shows oxygen production using a cryogenic oxygen generator 39 using air prepurification units 40 and 41 in combination with a cryogenic distillation unit 42 . The prepurification units 40 and 41 remove moisture and carbon dioxide from the compressed air supply 32 using either temperature swing adsorption or pressure swing adsorption processes. After being directed to the cryogenic unit 42 , the resulting purified air supply 43 is cooled to cryogenic temperatures, and separated into oxygen for use as oxygen supply 15 and a nitrogen supply 44 . The nitrogen supply 44 is divided, where one part becomes the waste gas supply 22 discussed above, and the other part becomes a regeneration supply 45 for the air prepurification units 40 and 41 . Intermittently, the process in the air prepurification units 40 and 41 is reversed to facilitate regeneration, and the regeneration supply 45 is used to regenerate the air repurification units 40 and 41 . After regeneration, the regeneration supply 45 exits the air prepurification units 40 and 41 as exhaust stream 46 .
If waste gas supply 22 is required at higher pressures, the cryogenic oxygen generator 39 of FIG. 2 can be modified. As in the case of the oxygen generator 23 of FIG. 1 , a separate compressed dry air supply can be produced when oxygen is made using cryogenic distillation. The resulting modified cryogenic oxygen generator 49 is depicted in FIG. 3 . In FIG. 3 , dryer beds 50 and 51 are used to dry the compressed air supply 32 . The resulting compressed dry air supply 52 is divided. One part becomes the waste gas supply 22 as discussed above, and the other part is directed to the air prepurification units 53 and 54 . As in FIG. 2 , the air prepurification units 53 and 54 of cryogenic oxygen generator 49 of FIG. 3 removes other impurities such as carbon dioxide from the compressed dry air supply 52 . Furthermore, after being directed to the cryogenic unit 55 , the resulting purified air supply 56 is cooled to cryogenic temperatures, and separated into oxygen for use as oxygen supply 15 and a nitrogen supply 57 . The nitrogen supply 57 is used to regenerate the air prepurification units 53 and 54 . Intermittently, the process in the air prepurification units 53 and 54 is also reversed to facilitate regeneration, and the nitrogen supply 57 exits the air prepurification units 53 and 54 and dryer beds 50 and 51 as exhaust stream 58 .
The general operation of the ozone production plant 10 using the various oxygen generators 23 , 39 , and 49 as described above eliminates the need for additional compression of the waste gas 22 . Furthermore, the cryogenic oxygen generators 39 and 49 are particularly suitable for large ozone use processes. These large use ozone processes include, among others, the LoTO x process for NO x abatement. For large ozone users, the oxygen supply 15 generated with the cryogenic oxygen generators 39 and 49 provides a much more cost effective alternative to other forms of oxygen generation.
Improvements to the ozone production plant 10 can be used to increase the efficiency of the ozone production process, and further reduce costs. For example, when vaporized liquid oxygen, such as being supplied from a liquid oxygen tank, is used to supply the ozone generator 11 as oxygen supply 15 , the vaporized liquid oxygen can also be used to simplify the recycling of the ozone-depleted oxygen supply 20 . As seen in FIG. 4 , the ozone-depleted oxygen supply 20 and a vaporized liquid oxygen supply 59 with an elevated pressure (up to 200 psig) are directed to an eductor 60 . At the eductor 60 , the gas supplies are mixed and the ozone-depleted oxygen supply 20 is therefore compressed. The effective compression of the ozone-depleted oxygen supply 20 forces the ozone-depleted oxygen supply 20 , as part of a mixed oxygen supply 61 , to the ozone generator 11 . The effective compression of the ozone-depleted oxygen supply 20 eliminates the need for the blower 21 .
Efficiency can also be increased by modifying the pressure swing adsorption process in the two tower PSA plant 12 . In other words, the pressure swing adsorption process is not limited to the various cycles described above, and additional or modified cycles can be used to improve efficiency. The pressure swing adsorption process in the two tower PSA plant 12 is described in Table 1 below.
TABLE 1
Bed of Second
Time
Bed of First Tower 13
Tower 14
Valves Open
(minutes)
Oxygen purge using
Ozone
V2, V3, V5, V6,
0.25
ozone-depleted oxygen
adsorption
V10
supply 20
Pressurization with
Ozone
V2, V5, V6, V10
0.25
ozone-depleted oxygen
adsorption
supply 20
Ozone adsorption
Purge using
V1, V4, V8, V9
4.5
waste gas 22
Ozone adsorption
Oxygen purge
V1, V4, V5, V6,
0.25
using ozone-
V9
depleted
oxygen
supply 20
Ozone adsorption
Pressurization
V1, V5, V6, V9
0.25
with ozone-
depleted
oxygen
supply 20
Purge using waste gas 22
Ozone
V2, V3, V7, V10
4.5
adsorption
FIG. 5 illustrates the configuration of the two tower PSA plant 12 facilitating the various cycles, and details the valves V 1 -V 4 forming the first switching system 17 and the valves V 5 -V 10 forming the second switching system 18 . Table 1 refers to the valves V 1 through V 10 depicted in FIG. 5 , and details which valves are opened during the various cycles of the pressure swing adsorption process. These cycles are effectuated by the intermittent opening and closing of valves V 1 through V 10 , and the actuation of the valves for specified periods of time (exemplified but not limited to those in Tables 1-4) is usually controlled by a programmable logic controller (not shown).
Although the entirety of the pressure swing process is described in Table 1, the first portion of the process will be described for purposes of illustration. As shown in Table 1, when the second tower 14 is undergoing the ozone adsorption cycle, the first tower 13 is undergoing the oxygen purge cycle. To perform these cycles, valves V 2 , V 3 , V 5 , V 6 , and V 10 are open for a selected period of time, for example, 0.25 minutes. As a result, part of the ozone-rich oxygen supply 16 is directed via valve V 2 to the second tower 14 .
The ozone adsorption bed of the second tower 14 adsorbs ozone from the ozone-rich oxygen supply 16 . The ozone-depleted oxygen supply 20 exits the second tower 14 , and is subsequently divided. A first part of the ozone-depleted oxygen supply 20 is directed to a first buffer tank 80 via valve V 10 , and is eventually recycled to the ozone generator 11 . A second part of the ozone-depleted oxygen supply 20 is directed to the first tower 13 via valves V 5 and V 6 .
During the oxygen purge cycle, the second part of the ozone-depleted oxygen supply 20 passes through the first tower 13 . Subsequently, the second part of the ozone-depleted oxygen supply 20 , and any contaminants collected during the oxygen purge cycle, are directed to a second buffer tank 81 . The second buffer tank 81 reduces the pressure fluctuations of gas supplies received therein. Furthermore, the second buffer tank 81 may also be used to reduce ozone concentration fluctuations. The gas supplies received in the second buffer tank 81 are eventually directed to the ozone utilization application, for example, a drinking water disinfection system. At the expiration of the oxygen purge cycle in the first tower 13 , the pressure swing adsorption process continues according to Table 1.
As discussed hereinabove, the adsorption beds of the first tower 13 and second tower 14 operate out of phase with one another. Such operation increases the efficiency of the process, by allowing the operation of one tower to complement the operation of the other tower. For example, the out of phase operation of the two tower PSA plant 12 , allows the ozone-depleted oxygen supply 20 exiting one tower to be used in the oxygen purge cycle of the other tower.
However, as seen in FIG. 6 , the efficiency of the pressure swing adsorption process can be increased by using a high purity oxygen supply 71 , rather than the ozone-depleted oxygen supply 20 during the oxygen purge and pressurization cycles. High purity oxygen supply 71 could be oxygen from a liquid oxygen tank or gaseous oxygen from a cryogenic oxygen generator such as oxygen supply 15 in FIGS. 2 and 3 . When the ozone-depleted oxygen supply 20 is recycled, this eventually results in an unacceptably large inerts concentration (more than 30%) in the ozone-depleted oxygen supply 20 eventually directed to the ozone generator 11 . For purposes of this specification, nitrogen and argon in air are considered inerts. The presence of such inerts can reduce the efficiency of the ozone generator 11 by more than 20%. However, the high purity oxygen supply 71 reduces the inerts concentration to less than about 5% in the ozone-depleted oxygen supply 20 directed to the ozone generator 11 . Such a concentration of nitrogen will have little effect on the efficiency of the ozone generator 11 . The improved pressure swing adsorption process using the high purity oxygen supply 71 , rather than the ozone-depleted oxygen supply 20 , is described in Table 2.
TABLE 2
Bed of First
Time
Tower 13
Bed of Second Tower 14
Valves Open
(minutes)
Oxygen purge
Ozone adsorption
V2, V3, V5, V10
0.25
using high
purity oxygen
supply 71
Pressurization
Ozone adsorption
V2, V5, V10
0.25
with high
purity oxygen
supply 71
Ozone
Purge using waste gas 22
V1, V4, V8, V9
4.5
adsorption
Ozone
Oxygen purge using high
V1, V4, V6, V9
0.25
adsorption
purity oxygen supply 71
Ozone
Pressurization with high
V1, V6, V9
0.25
adsorption
purity oxygen supply 71
Purge using
Ozone adsorption
V2, V3, V7, V10
4.5
waste gas 22
During the feed of the ozone-rich oxygen supply 16 to the adsorption beds of the first tower 13 and second tower 14 , ozone is adsorbed on the adsorption beds and oxygen passes through. During desorption using the waste gas supply 22 , ozone is desorbed from the adsorption beds and mixed with the waste gas supply 22 . The resulting supply mixture 24 of ozone and waste gas supply 22 is collected in the second buffer tank 81 before being sent to ozone utilization applications such as drinking water treatment. During desorption the concentration of ozone in the supply mixture 24 exiting the adsorption beds is not constant and can vary by a factor of two or more. The pressures and flow rates of the supply mixture 24 coming out of the adsorption beds may also vary. The second buffer tank 81 mixes the supply mixture 24 to provide a nearly constant ozone concentration and flow rate to the ozone utilization application. The required size of the ozone buffer tank can be determined experimentally or through process simulation.
The efficiency of the process can also be increased by reducing the size of the second buffer tank 81 . Because gas supplies are not directed to the second buffer tank 81 from either the first tower 13 or second tower 14 during their respective pressurization cycles as shown in Table 2, there are large pressure and concentration fluctuations in the second buffer tank 81 . To overcome these fluctuations, the size of the second buffer tank 81 must be increased significantly. However, large buffer tanks as compared to small buffer tanks increase the possibility of ozone decomposition, and as a result, decrease the efficiency of the process. Also large, ozone compatible buffer tanks, can be fairly expensive. If the backfill step is eliminated the size of the ozone buffer tank can be reduced by 50% or more since there is constant ozone flow to the ozone buffer.
To keep the size of the second buffer tank 81 small, the second buffer tank 81 has to receive a constant supply of gas containing ozone. Replacing the process described in Table 2 with the process described in Table 3 will provide such a constant supply of gas containing ozone.
TABLE 3
Bed of
Bed of
Time
First Tower 13
Second Tower 14
Valves Open
(minutes)
Oxygen purge
Ozone adsorption
V2, V3, V5, V10
0.25
using fresh
high purity
oxygen supply 71
Feed pressurization
Waste gas purge
V1, V4, V8, V9
0.25
with high purity
oxygen supply
71 and ozone
adsorption
Ozone adsorption
Waste gas purge
V1, V4, V8, V9
4.5
Ozone adsorption
Oxygen purge
V1, V4, V6, V9
0.25
using fresh
high purity
oxygen supply 71
Waste gas purge
Feed pressurization
V2, V3, V7, V10
0.25
with high purity
oxygen supply
71 and
ozone adsorption
Waste gas purge
Ozone adsorption
V2, V3, V7, V10
4.5
During the feed pressurization cycles shown in Table 3, the first tower 13 and second tower 14 will receive the ozone-rich oxygen supply 16 initially for pressurization and then for ozone adsorption and production of the ozone-depleted oxygen supply 20 . Therefore, the first tower 13 and second tower 14 are effectively pressurized without the need for the pressurization cycle of Table 2. Furthermore, during the process shown in Table 3 when one tower is undergoing the feed pressurization and ozone adsorption cycle, the other tower is undergoing either the waste gas purge cycle or oxygen purge cycle, and a constant supply of gas containing ozone is consequently supplied to the second buffer tank 81 .
The cycle in Table 3 will reduce the size and corresponding cost of the second buffer tank 81 . It will also reduce ozone decomposition inside the second buffer tank 81 through reduction in ozone residence time in the second buffer tank 81 . In addition to the process described in Table 3, other possibilities exist to reduce or eliminate the second buffer tank 81 . For example, if the ozone production plant 10 is used to treat large drinking or waste water supplies, then large basins for contacting ozone and water can themselves act as an ozone buffer to remove the aforementioned concentration fluctuations, and eliminate or substantially reduce the size of the second buffer tank 81 .
The efficiency of the process can further be increased by warming the waste gas supply 22 used during the waste gas purge cycle. As discussed above, compressed dry air supply 34 , 52 and nitrogen supply 44 are used as the waste gas supply 22 to desorb the ozone from the adsorption beds. Warming the waste gas supply 22 to about 10° C. to about 30° C. above the ozone-rich oxygen supply 16 , for at least part of the waste gas purge cycle, reduces the amount of waste gas supply 22 required. Furthermore, warming the waste gas supply 22 also allows use of higher pressures during the waste gas purge cycle than afforded during the desorption with waste gas supply 22 having temperatures similar to ozone-depleted supply 16 . As a result, a heater 92 may be provided as shown in FIG. 6 to heat the waste gas supply 22 . Furthermore, the heat of compression generated during the production of compressed dry air supply 34 , 52 can be used to heat the waste gas supply 22 when the compressed dry air supply 34 , 52 is generated. A representative cycle using the warmed waste gas supply 22 is described in Table 4.
TABLE 4
Bed of First
Time
Tower 13
Bed of Second Tower 14
Valves Open
(minutes)
Oxygen purge
Ozone adsorption
V2, V3, V5, V10
0.25
using high
purity oxygen
supply 71
Pressurization
Ozone adsorption
V2, V5, V10
0.25
with high
purity oxygen
supply 71
Ozone
Warm waste gas purge
V1, V4, V8, V9
2
adsorption
Ozone
Waste gas purge
V1, V4, V8, V9
2.5
adsorption
Ozone
Oxygen purge using high
V1, V4, V6, V9
0.25
adsorption
purity oxygen supply 71
Ozone
Pressurization with high
V1, V6, V9
0.25
adsorption
purity oxygen supply 71
Warm waste
Ozone adsorption
V2, V4, V8, V10
2
gas purge
Waste gas
Ozone adsorption
V2, V4, V8, V10
2.5
purge
The efficiency of the process can still further be increased by using a wet waste gas supply 22 during the waste gas purge cycle. Such a wet regeneration gas can be produced by compressing ambient air to the desorption pressure. Using wet waste gas supply 22 during the gas purge cycle results in some loss in adsorption capacity. However, overall ozone recovery may increase because ozone destruction (or decomposition) decreases significantly when using wet adsorbents. Also, significant energy savings can be realized by only drying the ozone-depleted oxygen supply 20 before entering the ozone generator 11 . As a result, the ozone-depleted oxygen supply 20 should be dried by some suitable drying process before going to the ozone generator 11 . These drying processes include, but are not limited to, PSA, TSA, or a suitable membrane. In fact, the amount of moisture in the oxygen supply 15 may be less than 10% of the moisture in the waste gas supply 22 and this results in significant regeneration energy savings.
The results of an experiment alternately using wet and dry nitrogen supplies 44 as the waste gas supply 22 are seen in FIGS. 7 and 8 . For example, ozone from the ozone-rich oxygen supply 16 (10% ozone in oxygen mixture) was adsorbed on an adsorption bed composed of silica gel for approximately 5 minutes. The adsorbed ozone was subsequently desorbed using wet and dry nitrogen supplies 44 for 5 minutes. The flow rates of the ozone-rich oxygen supply 16 and the wet and dry nitrogen supplies 44 were identical. The ozone concentrations at the outlet of the adsorption bed during cyclic adsorption and desorption are shown in FIGS. 7 and 8 . Comparison of the resulting ozone concentrations indicates that the adsorption capacity using a wet or dry nitrogen supply 44 are not significantly different.
Use of the wet waste gas supply 22 during regeneration makes possible the use of other adsorbents such as high silica mordenites and dealuminated Y zeolites. These adsorbents have ozone adsorption capacities two to three times that of silica gel. However, they can not be used when the adsorbent is dry because of significant ozone loss due to decomposition.
It will be understood that the embodiments described herein are merely exemplary and that a person skilled in the art may make many variations and modifications without departing from spirit and scope of the invention. The various embodiments may be practiced in the alternative, or in combination, as appropriate. All such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.
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Methods of providing ozone at a selected pressure above atmospheric pressure include supplying a purge gas supply ( 22 ) pressurized above the selected pressure to at least one ozone adsorption apparatus ( 12 ); desorbing ozone from the ozone adsorption apparatus ( 12 ) with the pressurized purge gas supply ( 22 ); and delivering a mixture of ozone and the purge gas supply ( 24 ) at the selected pressure without further compression.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority from Japanese Patent Application JP-2010-44753 filed on Mar. 1, 2010, the content of which is hereby incorporated by reference into this application.
TECHNICAL FIELD
[0002] The present invention relates to a sliding bearing excellent in anti-seizure property suitable for turbochargers of internal combustion engines.
BACKGROUND ART
[0003] Conventionally, the sliding bearing used in turbochargers of internal combustion engines has been required to have corrosion resistance and wear resistance properties, and it has been made of brass in which grains of Mn—Si compounds are dispersed in a matrix of the brass. There has been proposed such a sliding bearing in JP-A-2003-42145, according to which an extension direction of crystallized Mn—Si compounds crystallized in brass is arranged to correspond to an axial direction of a rotating shaft to be supported by the sliding bearing on a sliding surface of the sliding bearing. The technique disclosed in JP-A-2003-42145 is schematically illustrated in FIG. 3 (in which SD denotes a sliding direction and AD an axial direction, crystallized Mn—Si compounds 2 a are dispersed in a copper alloy matrix 1 a ). Depending on the direction of the crystallized Mn—Si compounds, an effect can be obtained, which effect is improvement of the wear resistance property of the sliding bearing.
[0004] With regard to the technique disclosed in JP-A-2003-42145, however, it was confirmed that in respect of the crystallized Mn—Si compounds, which exist on the sliding surface of the sliding bearing, and which extend to the axial direction of the rotating shaft, the larger the grain size (i.e. an extension length) increases, the more the wear resistance property is improved while the anti-seizure property is deteriorated.
[0005] During operation of the turbocharger of the internal combustion engine, the bearing use environment becomes a high temperature and the viscosity of lubricant oil drops. In the case where the oil viscosity excessively drops, an enough oil film is not formed in a clearance between the sliding surface of the sliding bearing and a mating shaft resulting in that both the sliding surfaces of the sliding bearing and the mating shaft are caused to directly contact. The sliding bearing disclosed in JP-A-2003-42145 has a disadvantage in that a sulfide film is hard to be formed on a surface of a brass matrix in the sliding surface of the sliding bearing, thus causing a contact of metals between the brass matrix and the mating shaft and thereby decreasing the anti-seizure property.
BRIEF SUMMARY OF THE INVENTION
[0006] In light of the above considerations, the present invention was proposed.
[0007] An object of the present invention is to provide a sliding bearing excellent in anti-seizure property, which is used in turbochargers of internal combustion engines.
[0008] Under the above object, according to the present invention, there is provided a sliding bearing used in turbochargers of internal combustion engines, which is formed with a copper alloy comprising, by mass, 25 to 45% Zn, 0.3 to 2.0% Si, 1.5 to 6.0% Mn, and the balance being Cu and unavoidable impurities, and which has a cylindrical shape for supporting a rotating shaft, wherein crystallized Mn—Si compounds, which extend in an axial direction of the rotating shaft on a sliding surface of the sliding bearing, are dispersed in a matrix of the copper alloy, and wherein the crystallized Mn—Si compounds have an average inter-grain distance of 20 to 80 μm.
[0009] According to a first embodiment of the present invention, the matrix of the copper alloy contains not only the crystallized Mn—Si compounds but also precipitated Mn—Si compounds which are dispersed in the matrix, and the Mn—Si compounds including the crystallized Mn—Si compounds and the precipitated Mn—Si compounds have an average inter-grain distance of 5 to 30 μm.
[0010] According to a second embodiment of the present invention, the copper alloy further comprises, by mass %, at least one element selected from the group consisting of Fe, Al, Ni, Sn, Cr, Ti, Mo, Co, Zr and Sb in a total amount of not more than 5%.
[0011] According to a third embodiment of the present invention, the copper alloy further comprises at least one element selected from the group consisting of Pb and Bi.
[0012] According to the invention sliding bearing, the crystallized Mn—Si compounds extending in the axial direction of the rotating shaft on the sliding surface of the sliding bearing are dispersed in the alloy matrix. The crystallized Mn—Si compounds consist of five Mn atoms and three Si atoms, and are dispersed in a form of acicular grains in the alloy matrix. With regard to the above recitation that the crystallized Mn—Si compounds, existing on the sliding surface of the sliding bearing, extend in the axial direction of the rotating shaft, as shown in FIG. 1 , it means that major axes of the crystallized acicular Mn—Si compounds extend in the axial direction of the rotating shaft on the sliding surface of the sliding bearing. By such an orientational arrangement of the crystallized acicular Mn—Si compounds, the wear resistance property of the sliding bearing is improved. Note that according to one aspect of the present invention, the crystallized Mn—Si compounds may be arranged to be oriented to the axial direction of the rotating shaft on the sliding surface of the sliding bearing at least on the sliding surface of the sliding bearing, while such an arrangement is not peculiar to the present invention and an obtainable technical effect thereby is disclosed in JP-A-2003-42145. Thus, a detailed description is omitted herein. Note also that it was experimentally confirmed that the crystallized Mn—Si compounds having an average longitudinal length (i.e. the average size of the major axe) of less than 10 μm loses the effect of improving the wear resistance property of the sliding bearing. Thus, the sliding bearing according to the aspect of the present invention requires the crystallized Mn—Si compounds to have an average longitudinal length (i.e. an average size of the major axes) of not less than 10 μm.
[0013] In the sliding bearing in which crystallized Mn—Si compounds are dispersed in the copper alloy matrix, when a temperature of the copper alloy rises during operation of the turbocharger, there will arise a difference in thermal expansion between the copper alloy matrix and the crystallized Mn—Si compounds thereby causing lattice defects (i.e. lattice strain) in an arrangement of the metal atoms forming the copper alloy matrix around the Mn—Si compounds. The copper alloy matrix with such lattice defects is in an active state and liable to react with sulfur contained in lubricant oil.
[0014] In the invention sliding bearing, the crystallized Mn—Si compounds dispersed in the copper alloy matrix have an average inter-grain distance of 20 to 80 μm, according to which arrangement of the crystallized Mn—Si compounds, the entire copper alloy matrix on the sliding surface of the sliding bearing is affected by the difference in thermal expansion between the copper alloy matrix and the crystallized Mn—Si compounds, so that the copper alloy matrix is uniformly active and a sulfide film can be formed early on a surface of the copper alloy matrix. Herein, the average inter-grain distance means an average value of the distance (d: see FIG. 1 ) between a surface of a grain of the Mn—Si compound in the copper alloy matrix and a surface of another grain of the Mn—Si compound closest to the former grain, and expresses an average length of the copper alloy matrix existing between both the adjacent Mn—Si compound grains. Since the invention sliding bearing has a feature that the crystallized Mn—Si compounds, extending in an axial direction of the rotating shaft on the sliding surface of the sliding bearing, are dispersed in the copper alloy matrix, and the crystallized Mn—Si compounds have an average inter-grain distance of 20 to 80 μm, when the turbocharger is operating, a nonmetallic sulfide film is formed in an early stage on the surface of the copper alloy matrix, thereby preventing occurrence of metal-to-metal sliding contact between the sliding bearing and the mating shaft to improve anti-seizure property of the sliding bearing.
[0015] It was experimentally confirmed that in the case of the crystallized Mn—Si compounds having the average inter-grain distance of less than 20 μm, the average longitudinal length (i.e. the average size of the major axe) is less than 10 μm. In this case, as set forth above, the improvement effect of wear resistance property of the sliding bearing is lost. In contrast to this, when the average inter-grain distance of the crystallized Mn—Si compounds exceeds 80 μm, the copper alloy matrix in or near a central region between Mn—Si compound grains is hardly affected by the difference in thermal expansion between the copper alloy matrix and the Mn—Si compounds during operation of the turbocharger, so that a sulfide film is hardly formed on a surface of the copper alloy matrix.
[0016] In the first embodiment of the invention, the matrix of the copper alloy contains not only the crystallized Mn—Si compounds but also precipitated Mn—Si compounds which are dispersed in the matrix. When casting the copper alloy, compounds of Mn and Si (i.e. the crystallized Mn—Si compounds) are crystallized in the molten copper alloy. When a cooling rate of the molten copper alloy is low, almost all of Mn and Si in the copper alloy are crystallized as the compounds. Thus, as shown in FIG. 1 in which SD denotes a sliding direction and AD an axial direction, the crystallized Mn—Si compounds 2 are dispersed in the copper alloy matrix 1. Contrasting, when the cooling rate of the molten copper alloy is higher, a part of Mn and Si in the copper alloy is dissolved oversaturatedly in the copper alloy matrix without crystallization to the Mn—Si compounds. Thus, as shown in FIG. 2 in which SD denotes a sliding direction and AD an axial direction, the precipitated Mn—Si compounds 3 are dispersed in the copper alloy matrix 1 among the crystallized Mn—Si compounds. The precipitated Mn—Si compounds in the invention copper alloy are relatively smaller than the crystallized acicular Mn—Si compounds, and are dispersed in a form of generally spherical grains, so that it is possible to make the average inter-grain distance of the Mn—Si compounds smaller since the precipitated Mn—Si compounds are dispersed in the copper alloy matrix between the crystallized Mn—Si compounds, while the spherical grains have not much effect on the wear resistance property. In this connection, it was experimentally confirmed that the dispersion state of the precipitated Mn—Si compounds can be controlled by setting appropriate casting conditions and conducting heat treatment.
[0017] In the first embodiment of the invention, the Mn—Si compounds including the crystallized Mn—Si compounds and the precipitated Mn—Si compounds have an average inter-grain distance of 5 to 30 μm. According to this feature, the entire copper alloy matrix of the sliding surface of the sliding bearing is liable to be affected by the difference in thermal expansion between the crystallized Mn—Si compounds and the precipitated Mn—Si compounds, so that a sulfide film can be formed in an early stage on the entire surface of the copper alloy matrix.
[0018] Further it was experimentally confirmed that when the average inter-grain distance of the Mn—Si compounds including the crystallized Mn—Si compounds and the precipitated Mn—Si compounds is less than 5 μm, the longitudinal length (i.e. a size of the major axes) of the crystallized Mn—Si compounds is less than 10 μm. This will be because in the case where the average inter-grain distance is intended to make smaller by increasing the number of precipitated Mn—Si compounds, it is needed to make a cooling rate of the molten copper alloy higher when casting thereby restraining the crystallized Mn—Si compounds from growing larger.
[0019] Zn is an element contributing to improvement of corrosion resistance property, so that the invention copper alloy comprises 25 to 45% Zn. In the case of less than 25% Zn, the copper alloy can not have satisfactory corrosion resistance property. In the case of more than 45% Zn, the copper alloy becomes brittle. More preferably, the Zn amount is in a range of 28 to 40%.
[0020] Si is an element which reacts with Mn to form a compound contributing to improving wear resistance property, so that the invention copper alloy comprises 0.3 to 2.0% Si. In the case of less than 0.3% Si, only a small amount of the Mn—Si compounds are formed, so that the copper alloy can not have satisfactory wear resistance property. In the case of more than 2.0% Si, an excessive amount of the Mn—Si compounds are formed, so that the copper alloy becomes brittle. More preferably, the Si amount is in a range of 0.6 to 1.4%.
[0021] Mn reacts with Si to form a compound contributing to improving wear resistance property, so that the invention copper alloy comprises 1.5 to 6.0% Mn. In the case of less than 1.5% Mn, only a small amount of the Mn—Si compounds are formed, so that the copper alloy can not have satisfactory wear resistance property. In the case of more than 6.0% Mn, the copper alloy becomes brittle. More preferably, the Mn amount is in a range of 2.0 to 4.0%.
[0022] In the second embodiment of the present invention, the copper alloy further comprises at least one element selected from the group consisting of Fe, Al, Ni, Sn, Cr, Ti, Mo, Co, Zr and Sb in a total amount of not more than 5%. These elements contribute to strengthening the copper alloy matrix. In the case of less than 0.1% of the element(s), the copper alloy has not such an effect. In the case of more than 5% of the element(s), the copper alloy becomes brittle. These elements may be combined with Mn and Si to form compounds. The crystallized Mn—Si compounds or the precipitated Mn—Si compounds in the invention alloy may be a compound(s) with one or more of these elements.
[0023] In the third embodiment of the present invention, the copper alloy may further comprise a total of not more than 5% of at least one element selected from Pb and Bi. In the case of less than 0.1% of the element(s), the copper alloy does not have such an effect. In the case of more than 5% of the element(s), the copper alloy becomes brittle.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0024] FIG. 1 is a schematic drawing showing a sliding surface of a sliding bearing, on which crystallized Mn—Si compounds are dispersed in a copper alloy matrix;
[0025] FIG. 2 is a schematic drawing showing a sliding surface of a sliding bearing, on which crystallized Mn—Si compounds and precipitated Mn—Si compounds are dispersed in the copper alloy matrix; and
[0026] FIG. 3 is a schematic drawing showing a sliding surface of a conventional sliding bearing, on which crystallized Mn—Si compounds are dispersed in the copper alloy matrix.
DETAILED DESCRIPTION OF THE INVENTION
Example
[0027] Invention specimens A to F and comparative specimens A to C made of copper alloys, in which Mn—Si compounds are dispersed, were prepared for the purpose of measuring the average inter-grain distance of the Mn—Si compounds, an evaluation of a sulfide film formation and a seizure test. Table 1 shows chemical compositions of the invention specimens A to F and the comparative specimens A to C. For each of the invention specimens A to F and the comparative specimens A to C, a copper alloy shown in Table 1 was cast, and the thus obtained casting was subjected to hot extrusion to produce a cylindrical sliding bearing. When casting, Mn—Si compounds were crystallized in the copper alloy matrix. The cast copper alloy was subjected to hot extrusion and then arranged in such a manner that the crystallized Mn—Si compounds extend in an axial direction of a mating shaft on a sliding surface of the sliding bearing. Further, control was made in such a manner that the average inter-grain distance of the Mn—Si compounds dispersed in the copper alloy matrix on the sliding surface of the sliding bearing matches the distance shown in Table 1 by changing the casting conditions for making the cast copper alloy and the hot extruding conditions.
[0000]
TABLE 1
Average
Whether a
Critical
inter-grain
sulfide film
specific load
Chemical Composition (mass %)
distance
is present or
for seizure
Material
Cu
Zn
Mn
Si
Fe
Al
Ni
Sn
Pb
Bi
(μm)
not
(MPa)
Invention
A
Balance
35.0
3.0
1.0
—
—
—
—
—
—
50
YES
27
Specimen
B
Balance
35.0
1.5
0.3
—
—
—
—
—
—
80
YES
21
C
Balance
35.0
6.0
2.0
—
—
—
—
—
—
20
YES
33
D
Balance
35.0
3.0
1.0
—
—
—
—
—
—
15
YES
39
E
Balance
35.0
6.0
2.0
—
—
—
—
—
—
10
YES
42
F
Balance
35.0
3.0
1.0
0.1
1.0
0.05
0.05
0.03
0.8
50
YES
30
Comparative
A
Balance
35.0
3.0
1.0
—
—
—
—
—
—
120
NO
9
Specimen
B
Balance
35.0
6.0
2.0
—
—
—
—
—
—
100
NO
12
C
Balance
35.0
1.0
0.2
—
—
—
—
—
—
130
NO
6
[0028] The invention specimens A to C were formed from the copper alloys comprising 35% Zn, 0.3 to 2.0% Si, 1.5 to 6.0% Mn, and the balance of Cu. Control was made so that the average inter-grain distance of the crystallized Mn—Si compounds dispersed in the copper alloy matrix well within a range of 20 to 80 μm by properly choosing casting and extruding conditions. It was experimentally confirmed that when the invention specimens A to F were cast of an alloy comprising 25 to 45% by mass of Zn, control was able to be made so that the average inter-grain distance of the crystallized Mn—Si compounds fell within a range of 20 to 80 μm.
[0029] The invention specimens D and E had the same alloy composition as that of the invention specimens A and C respectively except that control was made such that the cooling rate of the molten copper alloy was increased more than that of the invention specimens A to C, a part of the Mn and Si contained in the copper alloy was changed into an oversaturated solid solution in the copper alloy matrix without being crystallized as the Mn—Si compounds, thereby not only the crystallized Mn—Si compounds but also the precipitated Mn—Si compounds were dispersed in the copper alloy matrix, and in addition control was made such that the average inter-grain distance of the Mn—Si compounds including the crystallized Mn—Si compounds and the precipitated Mn—Si compounds fell within a range of 5 to 30 μm.
[0030] Control was made so that the invention specimen F was cast of an alloy adding Fe, Al, Ni, Sn, Pb and Bi to the invention specimen A and made under the same conditions as those for the invention specimens A to C, and thereby the average inter-grain distance of the crystallized Mn—Si compounds dispersed in the copper alloy matrix fell within a range of 20 to 80 μm. Note that it has been experimentally confirmed that regardless of the elements of the invention specimen F, control was able to be made so that the average inter-grain distance of the crystallized Mn—Si compounds fell within a range of 20 to 80 μm even by adding Cr, Ti, Mo, Co, Zr, and Sb to the copper alloy of the present application.
[0031] The comparative specimens A and B had the same alloy composition as that of the invention specimens A and C respectively except that at casting the crystallized Mn—Si compounds were grown larger in order to extremely improve the wear resistance property. As a result, the average inter-grain distance of the crystallized Mn—Si compounds was greater than 80 μm.
[0032] The comparative specimen C comprises a less amount of Mn and Si than the invention specimens A to C and thus comprises a less crystallized amount of Mn—Si compound than the invention specimens A to C. As a result, under the same conditions as those for the invention specimens A to C, the average inter-grain distance of the crystallized Mn—Si compounds was greater than 80 μm.
[0033] Here, the average inter-grain distance of the Mn—Si compound refers to an average value of the distance between a surface of a grain of a Mn—Si compound dispersed in the copper alloy matrix and a surface of a grain of another Mn—Si compound closest to the grain. An electronic microscope was used to take an image of a composition image of a bearing sliding surface at 200-fold magnification and then from the obtained composition image, the average inter-grain distance was measured by a general image analysis method (analysis software such as: Image-Pro Plus (Version 4.5) manufactured by Planetron, Inc). The measured results were shown in Table 1.
[0034] Next, the sliding bearing of each of the invention specimens A to F and the comparative specimens A to C was checked to evaluate whether a sulfide film was formed or not. First, the sliding bearing of each of the invention specimens A to F and the comparative specimens A to C was visually checked to confirm that the sliding surface had a metallic luster (golden color for a brass alloy). Then, a bearing tester was used to perform a sliding test on the sliding bearings of the invention specimens A to F and the comparative specimens A to C under the conditions shown in Table 2. After the sliding test, the sliding surface of each sliding bearing was visually checked to confirm whether or not the sliding surface had a metallic luster to evaluate whether a sulfide film was formed or not. The evaluation was made in such a manner that when the entire sliding surface of the sliding bearing after the sliding test lost a metallic luster, a determination was made that a sulfide film was “YES”, and when a part of the sliding surface had a metallic luster, a determination was made that a sulfide film was “NO”. The evaluation results were shown in Table 1.
[0000]
TABLE 2
Testing method
Bushing test
Inner diameter of sliding bearing
20
mm
Peripheral speed
10
m/second
Load
1
Mpa
Lubricant oil
Engine oil
Temperature of lubricant oil
150°
C.
Testing time
One hour
[0035] For each of the invention specimens A to F, a uniform sulfide film was formed on each surface of the copper alloy matrix of the sliding surface of the sliding bearing, while for each of the comparative specimens A to C, most of the sliding surfaces had a metallic luster and no sulfide film was formed on the entire surface of the copper alloy matrix on the sliding surface of the sliding bearing. Here, the invention specimens A to C, and F were configured such that the average inter-grain distance of the crystallized Mn—Si compounds dispersed in the copper alloy matrix fell within a range of 20 to 80 μm, while the invention specimens D and E were configured such that the average inter-grain distance of the Mn—Si compounds including the crystallized Mn—Si compounds and the precipitated Mn—Si compounds dispersed in the copper alloy matrix fell within a range of 5 to 30 μm. Therefore, the entire copper alloy matrix on the sliding surface of the sliding bearing was affected by the difference in thermal expansion between the copper alloy matrix and the Mn—Si compound. Therefore, the copper alloy matrix is uniformly active and a uniform sulfide film was formed on the surface of the copper alloy matrix.
[0036] In contrast to this, the comparative specimens A to C were configured such that the average inter-grain distance of the crystallized Mn—Si compounds dispersed in the copper alloy matrix exceeded 80 μm, and thus the copper alloy matrix near the central portion between Mn—Si compound grains was unlikely to be affected by the difference in thermal expansion between the copper alloy matrix and the Mn—Si compound. Thus, no uniform sulfide film was formed on the surface of the copper alloy matrix.
[0037] Next, a bearing tester was used to perform a seizure test on each sliding bearing of the invention specimens A to F and the comparative specimens A to C under the conditions shown in Table 3. Note that when the backing temperature of the sliding bearing was 250° C., a determination was made that a seizure occurred. The limit loads (surface pressures) at which no seizure occurred were shown in Table 1.
[0000]
TABLE 3
Testing method
Bushing test
Inner diameter of sliding bearing
20
mm
Peripheral speed
10
m/second
Load
Each increment of
load: 3 MPa/10 min.
Lubricant oil
Engine oil
Temperature of lubricant oil
100°
C.
[0038] When an evaluation was made as to whether a sulfide film was formed or not, the invention specimens A to F in which a sulfide film was formed early on a surface of the copper alloy matrix on the sliding surface of the sliding bearing had a high anti-seizure property, while the comparative specimens A to C in which a sulfide film was not early formed had a low anti-seizure property. This is because the invention specimens A to F had a nonmetal sulfide film which was formed early on the surface of the copper alloy matrix on the sliding surface of the sliding bearing and which prevented sliding of the metal surfaces between the sliding surface and the mating shaft surface. Further, the invention specimens D and E were such that not only crystallized Mn—Si compounds but also precipitated Mn—Si compounds were dispersed in the copper alloy matrix, and thereby the average inter-grain distance of the Mn—Si compounds including the crystallized Mn—Si compounds and the precipitated Mn—Si compounds was reduced and a sulfide film was formed earlier. That was considered to cause a particularly high anti-seizure property.
[0039] It should be further understood by those skilled in the art that although the foregoing description has been made on embodiments of the invention, the invention is not limited thereto and various changes and modifications may be made without departing from the spirit of the invention and the scope of the appended claims.
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Disclosed is a sliding bearing used in turbochargers of internal combustion engines. It is formed with a copper alloy containing, by mass %, 25 to 45% Zn, 0.3 to 2.0% Si, 1.5 to 6.0% Mn, and the balance being Cu and unavoidable impurities. The sliding bearing has a cylindrical shape for supporting a rotating shaft. Crystallized Mn—Si compounds are dispersed in a matrix of the copper alloy, the compounds extending in an axial direction of the rotating shaft on a sliding surface of the sliding bearing. The crystallized Mn—Si compounds have an average inter-grain distance of 20 to 80 μm. The matrix may contain precipitated Mn—Si compounds as well as the crystallized Mn—Si compounds.
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BENEFIT OF PROVISIONAL APPLICATION
This application claims the benefit of U.S. Provisional Application No. 60/842,759, filed 7 Sep. 2006.
FIELD
The present invention relates to nuclear magnetic resonance imaging and magnetic materials.
BACKGROUND
Nuclear magnetic resonance (NMR) refers to the response of atomic nuclei to magnetic fields. It is applicable to nuclei having an odd number of protons or neutrons, or both. In many applications, the nuclei is that of hydrogen (a proton), where the hydrogen is part of the water molecule.
A static magnetic field is applied to the sample of interest, which causes a precession of the nuclei at the Larmor frequency, proportional to the strength of the applied static magnetic field. The applied static magnetic field has a non-zero spatial gradient, so that the Larmor frequency of a nucleus is a function of its position in the sample of interest. The macroscopic magnetization is parallel with the direction of the static magnetic field.
Applying an oscillating magnetic field perpendicular to the static magnetic field and at a frequency equal to the Larmor frequency tips the magnetization. The tip angle is proportional to the product of the amplitude of the oscillating magnetic field with the time over which it is applied. The nuclei with the Larmor frequency precess in phase with one another.
A 90° pulse refers to a pulsed oscillating magnetic field that tips the magnetization to a direction along a plane transverse to the direction of the static magnetic field. After the 90° pulse, the nuclei population begins to dephase, that is, they lose their phase coherency. This decreases the net magnetization, which may be detected by a receiver coil. The measured decay is called the free induction decay.
In spin-echo detection, a sequence of 180° pulses (oscillating magnetic field pulses that change the tip angle by 180°) follows the 90° pulse. The first 180° pulse reverses the dephasing of the magnetization among the nuclei population, so that after some period of time the nuclei tend to be in phase, and a spin-echo signal is generated that is detectable in a receiver coil. The sequence of 180° pulses causes a sequence of spin-echo signals, but with decreasing signal strength over the sequence of 180° pulses.
In gradient-echo detection, a sequence of gradient defocusing and focusing follows an excitation pulse. The application of the defocusing and refocusing magnetic gradient changes generates a detectable echo signal in a receiver coil, but with decreasing signal strength with increasing repetitions of magnetic gradient defocusing and refocusing, and increases in time required for magnetic gradient defocusing and refocusing.
Because the Larmor frequency is a function of position due to the gradient in the static magnetic field, NMR imaging is realized by changing the frequency of the oscillating magnetic nuclei and analyzing the resulting spin-echo or gradient-echo signals. However, in applications to medical imaging of the human body, there may be various medical implants whose magnetic susceptibility does not match that of the surrounding tissue. A mismatch in magnetic susceptibility will affect the magnetization, which may lead to imaging artifacts in NMR. For example, relatively small deviations in the magnetic field may result in the displacement of several voxels when performing NMR imaging. Furthermore, signal loss may occur due to dephasing. During the acquisition when the free induction signal is refocused, the average frequency of the protons should remain constant. But in areas where there are deviations in the magnetic field homogeneity, the received signal is reduced because of the loss in refocusing.
Acrylics used in dental work are manufactured to be radio-opaque, so that they may be imaged in an x-ray. However, various materials in the acrylics may have a susceptibility different from that of air or water, which may cause unwanted artifacts in an NMR image. As another example, various ceramics may be used in hip replacements and other medical implants, where the magnetic susceptibilities of such ceramics may not match the surrounding tissue susceptibility (e.g., the susceptibility of water).
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a flow diagram according to an embodiment of the present invention.
FIG. 2 illustrates measured resonant frequencies at two locations, with one location including an embodiment of the present invention.
FIG. 3 illustrates measured resonant frequencies at two locations, with one location including another embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
In the description that follows, the scope of the term “some embodiments” is not to be so limited as to mean more than one embodiment, but rather, the scope may include one embodiment, more than one embodiment, or perhaps all embodiments.
Embodiments provide for biocompatible materials having a magnetic susceptibility matched to their surrounding tissue, or to air. For isotropic and linear materials, the magnetic induction {right arrow over (B)} and the magnetic field {right arrow over (H)} are related by {right arrow over (B)}=μ 0 (1+χ m ){right arrow over (H)}, where μ 0 is the permeability of free space, and χ m is the magnetic susceptibility. The permeability μ is μ=(1+χ m ). Paramagnetic material has a positive magnetic susceptibility, so that the permeability is greater than one. In this case, the magnetic induction is increased in the material when compared to free space. Diamagnetic material has a negative magnetic susceptibility, so that the permeability is less than one. In this case, the magnetic induction is decreased in the material when compared to free space. Embodiments modify NMR imaging compatible materials to make their magnetic susceptibility closer to air, or human tissue, by balancing net paramagnetic material with diamagnetic material, and by balancing net diamagnetic material with paramagnetic material. This procedure is illustrated in the flow diagram of FIG. 1 . If a material is measured as paramagnetic ( 102 ), then diamagnetic material is added ( 104 ) to bring the magnetic susceptibility sufficiently close to the intended surrounding tissue, whereas if the material is diamagnetic, then paramagnetic material is added ( 106 ).
Embodiments may use one or more diamagnetic materials selected from the group: Al 2 O 3 ; Al 2 (SO 4 ) 3 ; Al2(SO 4 ) 3 *2H 2 O; Sb 2 O 3 ; BaO; BaO 2 ; Bi; BiI 3 ; BiO; Bi 2 (SO 4 ) 3 ; Bi 2 S 3 ; B 2 O 3 ; Ca(C 2 H 3 O 2 ) 2 ; CaBr 2 * nH 2 O; GaI 3 ; Ga 2 O; GeO; GeO 2 ; HfO 2 ; In 2 O; In 2 O 3 ; I 2 O 5 ; PbO; MgO; SeO 2 ; SiO 2 ; Ag 2 O; AgO; Na 2 O; Na 2 O 3 ; SrO; SrO 2 ; ThO 2 ; SnO; SnO 2 ; WO 3 ; ZnO; ZrO; ZrO 2 . In the above group, n in nH 2 O is an integer.
Embodiments may use one or more paramagnetic materials chosen from the group: Ce; Ce 2 S 2 ; CsO 2 ; Cr 2 (C 2 H 3 O 2 ) 3 ; CrCl 2 ; CrCl 3 ; Cr 2 (SO 4 ) 2 ; Cr 2 (SO 4 ) 2 * nH 2 O; Co(C 2 H 3 O 2 ) 2 ; CoBr 2 ; CoCl 2 ; CoCl 2 *nH 2 O; CoF 2 ; CoI 2 ; Co 3 (PO 4 ) 2 ; CoSO 4 ; Co(SCN) 2 ; Dy; DyO 3 ; Dy 2 (SO 4 ) 3 ; Dy 2 (SO 4 ) 3 * nH 2 O; Dy 2 S 3 ; Er; Er 2 O 3 ; Er 2 (SO 4 ) 3 * nH 2 O; Er 2 S 3 ; Eu; EuBr 2 ; EuCl 2 ; EuF 2 ; EuI 2 ; Eu 2 O 3 ; EuSO 4 ; Eu 2 (SO 4 ) 3 ; Eu 2 (SO 4 ) 3 * nH 2 O; EuS; Gd; GdCl 3 ; Gd 2 O 3 ; Gd 2 (SO 4 ) 3 ; Gd 2 (SO 4 ) 3 * nH 2 O; Gd 2 S; Ho 2 O 3 ; Ho 2 (SO 4 ) 3 ; Ho 2 (SO 4 ) 3 * nH 2 O; FeBr 2 ; FeCO 3 ; FeCl 2 ; FeCl 2 * nH 2 O; FeCl 3 ; FeCl 3 *nH 2 O; FeF 2 ; FeF 3 ; FeF 3 * nH 2 O; FeI 2 ; Fe(NO 3 ) 3 * nH 2 O; FeO; Fe 2 O 3 ; FePO 4 ; FeSO 4 ; FeSO 4 *nH 2 O; Mn(C 2 H 3 O 2 ) 2 ; MnBr 2 ; MnCO 3 ; MnCl 2 ; MnCl 2 * nH 2 O; MnF 2 ; MnF 3 ; Mn(OH) 2 ; MnI 2 ; MnO; Mn 2 O 3 ; Mn 3 O 4 ; Mn s O 4 ; MnSO 4 * nH 2 O; MnS; Nd; NdF 3 ; Nd(NO 3 ) 3 ; Nd 2 O 3 ; Nd 2 (SO 4 ) 3 ; Nd 2 S 3 ; NiBr 2 ; NiCl 2 ; NiCl 2 * nH 2 O; Ni(OH) 2 ; Re; Ta 2 O 5 ; Tb; Tb 2 O 3 ; Tb(SO 4 ) 3 ; Tb(SO 4 ) 3 * nH 2 O; Tm; Tm 2 O 3 ; V 2 O 3 ; V 2 S 3 ; WS 2 ; Yb 2 S 3 ; Y 2 O 3 .
For some embodiments, volume magnetic susceptibility may be considered balanced if the susceptibility (when using SI units) is in the range of −50 ppm to 50 ppm (where ppm means parts per million). That is, for some embodiments, diamagnetic or paramagnetic material may be added to biocompatible materials used for implants such that the magnetic susceptibility is in the range of −50*10 −6 to 50*10 −6 (SI units). This particular range incorporates volume magnetic susceptibilities of air (0.38 ppm), water (−9.0 ppm), and various organic materials (approximately 6 ppm).
Other materials may be used in other embodiments. For example, Table 1 and the accompanying FIG. 2 provide experimental results of adding neodymium oxide, Nd 2 O 3 , a paramagnetic material, to a ceramic. The ceramic used was 750 Rescor™ Cercast ceramic, a product from Cortronics Corp. of Brooklyn, N.Y. The “750 Mix” referred to in the first column of Table 1 is this ceramic product. The “750 Activator” is a product provided by Cortronics Corp. that is used with the 750 Mix to form the ceramic. The third column in Table 1 provides the gram weight of the added Nd 2 O 3 .
The resulting ceramic was placed on a 500 ml square bottle. For each mixture, the NMR resonant frequency was measured at two locations (one near the ceramic sample that was tested and one further away), and the difference in frequency was plotted as a circle in FIG. 2 . Line 202 is an interpolated line through these measurements. Dashed line 204 is the measured resonant frequency at a different location in the bottle that does not have the ceramic (air only). The intersection of the interpolated line and dashed line provides the percentage concentration of Nd 2 O 3 in which the magnetic susceptibility of the ceramic matches that of air. In the particular example of FIG. 2 , the concentration of Nd 2 O 3 at the intersection is approximately 1.5 percent.
TABLE 1
750 Mix (g)
750 Activator (g)
Nd 2 O 3 (g)
7
1.8
0
7
1.8
0.005
7
1.8
0.015
7
1.8
0.025
7
1.8
.040
7
1.8
.060
7
1.8
.080
7
1.8
.100
7
1.8
.120
7
1.8
.150
As another example, Table 2 and the accompanying FIG. 3 provide experimental results of adding nickel (II) chloride, NiCl 2 *6H 2 O, a paramagnetic, to a polymer. The polymer used was an acrylic resin manufacture by Harry J. Bosworth company, marketed as Duz-All®. This is referred to in the first column of Table 2 as “Acrylic Resin”. The second column in Table 2 is the gram weight of an activator used with the acrylic resin. This is referred to as “MMA” for methlymethacrylate monomer. The third column in Table 2 provides the gram weight of the added NiCl 2 *6H 2 O.
The resulting acrylic was placed on a 500 ml square bottle, and for each mixture the NMR resonant frequency was measured at two locations (one near the ceramic sample that was tested and one further away), and the difference in frequency was plotted as a circle in FIG. 3 . Line 302 is an interpolated line through these measurements. Dashed line 304 is the measured resonant frequency at a different location in the bottle that does not have the polymer resin (air only). The intersection of the interpolated line and dashed line provides the percentage concentration of NiCl 2 in which the magnetic susceptibility of the polymer resin matches that of air. In the particular example of FIG. 3 , the concentration of NiCl 2 at the intersection is close to 4.7 percent.
TABLE 2
Acrylic Resin (g)
MMA (g)
NiCl 2 * 6H 2 O (g)
5
2.7
0
5
2.7
0.02
5
2.7
0.04
5
2.7
0.06
5
2.7
0.08
5
2.7
0.10
5
2.7
0.12
5
2.7
0.14
5
2.7
0.16
5
2.7
0.18
5
2.7
0.20
5
2.7
0.22
5
2.7
0.24
Methods other than that discussed in relation to FIGS. 2 and 3 may be used to determine the concentration of a diamagnetic or paramagnetic additive to ceramic or polymer medical implant material. For example, the susceptibility may be measured directly rather than measuring the resonant frequency at two different locations, one location with the ceramic or polymer, and one location without.
For some embodiments, the susceptibility of the implant material with additive may be adjusted to fall within some specified interval, or within some percent error from a specified target. For example, if the surrounding tissue or environment has a susceptibility χ 0 , then additives may be added so that the susceptibility χ m of the resulting mixture is such that χ m ε [χ 0 (1−Δ), χ 0 (1+Δ)]. More generally, χ m ε [χ L , χ U ], where χ L is a lower bound to the interval and χ U is an upper bound to the interval.
Although the subject matter has been described in language specific to structural features and methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims. Accordingly, various modifications may be made to the described embodiments without departing from the scope of the invention as claimed below.
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Materials suitable for medical and dental implants with magnetic susceptibility matched to surrounding environment to reduce artifacts in nuclear magnetic resonance imaging. Paramagnetic and diamagnetic materials may be added to ceramics and polymer resins to adjust magnetic susceptibility. Other embodiments are described and claimed.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 11/924,656, filed on Oct. 26, 2007, now pending, which is a continuation of U.S. application Ser. No. 11/593,082, filed on Nov. 6, 2006, now U.S. Pat. No. 7,293,189, which is a continuation of U.S. application Ser. No. 10/305,020, filed on Nov. 27, 2002, now U.S. Pat. No. 7,181,636, which claims the benefit of a foreign priority application filed in KOREA on Nov. 27, 2001, as Serial No. 10-2001-0074382. This application claims priority to all of these applications, and all of these applications are incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a method of recording additional data such as lyric and user input data to be in synchronization with audio data on a rewritable recording medium, and of reproducing them synchronously therefrom.
[0004] 2. Description of the Related Art
[0005] A disk-type recording medium such as a Compact Disk (CD) can store high-quality digital audio data permanently, so that it is very popular recording medium in these days.
[0006] Recently, a Digital Versatile Disk (called ‘DVD’ hereinafter) has been developed as a new disk-type recording medium. A DVD can store much more data than a CD, that is, high-quality moving pictures or audio data are recorded on a DVD for much longer time. Therefore, a DVD will be used widely in the near future.
[0007] There are three types of DVDs—DVD-ROM for read-only, DVD-R for write-once, and DVD-RAM or DVD-RW for rewritable. For a rewritable DVD, the standardization of data writing format is in progress.
[0008] FIG. 1 is a block diagram of an optical disk device that records/reproduces audio data to/from a recording medium.
[0009] The disk device configured as FIG. 1 comprises an optical pickup 11 reading signals recorded on a rewritable DVD 10 such as a DVD-RW and writing data streams processed into writable signals onto the rewritable DVD 10 ; a reproduced signal processor 12 restoring the read signals into compressed digital data; a decoder 13 decoding the compressed digital data to original data; a sampler 18 digitizing an inputted analog signal at a preset sampling rate; an encoder 17 encoding the digitized LPCM data into MPEG-, or AC3-formatted data; a writing processor 16 converting the encoded data from the encoder 17 or LPCM data from the sampler 18 into signals suitable to be written; a controller 14 controlling all elements to conduct user's commands such as playback or record; and a memory 15 for storing data temporally.
[0010] If an analog signal is applied to the disk device of FIG. 1 , the sampler 18 samples the analog signal at the preset sampling rate. Each sampled signal, which is LPCM data, is is applied to the encoder 17 that encodes a block of sampled data into compressed data of pre-specified format, for example, MPEG format. The compressed data are then applied to the writing processor 16 .
[0011] The writing processor 16 converts a series of the compressed data into binary signals which are written in mark/space patterns on the writable DVD 10 . Already-compressed digital data from outside are directly processed by the writing processor 16 to be written onto the writable DVD 10 .
[0012] After recording of audio data, navigation data for the audio data are created and then recorded on the writable DVD 10 .
[0013] FIG. 2 shows the structure of RTR_AMG (Real Time Record Audio ManaGement) recorded as navigation data on a rewritable disk. The RTR_AMG includes RTR_AMGI (RTR Audio Manager General Information), AUDFIT (AUDio File Information Table), ASVFIT (Audio Still Video File Information Table), ORG_PGCI (ORGiginal PGC (ProGram Chain) Information), UD_PGCIT (User Defined PGC Information Table), TXTDT_MG (TeXT DaTa ManaGer), and MNFIT (MaNufacturer's Information Table).
[0014] The TXTDT_MG can include additional data of recorded songs such as lyrics. Therefore, when the controller 14 selects and reproduces a recorded song from the rewritable disk 10 , it is able to present lyric text in characters on a screen by reading it from the TXTDT_MG.
[0015] Consequently, when a user selects a recorded song to play back from the rewritable DVD 10 , he or she is able to view its lyric on a screen.
[0016] However, each of additional data such as a lyric included in the TXTDT_MG is linked with a recorded song wholly. In other words, a lyric in the TXTDT_MG cannot have information to synchronize in detail with a recorded song. Therefore, it is impossible to display lyric data step by step at the same speed that the recorded song is reproduced from a rewritable DVD.
SUMMARY OF THE INVENTION
[0017] It is an object of the present invention to provide a synchronizing method that records additional data such as lyric data and user input data to be synchronized minutely with audio data on a rewritable recording medium.
[0018] It is another object of the present invention to provide a synchronizing method that reproduces synchronously audio data and additional data thereof that have been recorded with minutely-synchronizing information.
[0019] It is another object of the present invention to provide a method and apparatus for providing data structures that allow a synchronous reproduction of main data and additional data, which address the limitations and disadvantages associated with the related art.
[0020] An audio data related information recording method in accordance with an aspect of the present invention segments additional information related with audio data recorded on a rewritable recording medium, records the information segments, and further records synchronizing information, e.g., time length to keep up presentation of each information segment or start time to present each information segment, in the vicinity of said each information segment in order to present each information segment in synchronization with a corresponding part of the recorded audio data.
[0021] An audio data related information reproducing method in accordance with an aspect of the present invention reads sequentially a plurality of information segments constituting a piece of additional information related with audio data recorded on a rewritable recording medium, and makes presentation of each information segment based on synchronizing information, e.g., time length to keep up presentation of each information segment or start time to present each information segment, recorded in association with each information segment in order to present each information segment in synchronization with a corresponding part of the recorded audio data.
[0022] According to an aspect of the present invention, there is provided a method of reproducing main data and additional data, the method comprising: receiving the additional data associated with the main data, the additional data being divided into a plurality of segment units; and reproducing the additional data in a synchronous manner with the main data using time information if indication information indicates a presence of the time information, wherein the time information indicates a presentation time of the additional data with respect to the main data, and wherein the main data and the additional data are reproduced according to management data, the management data including link information for linking the main data and the additional data.
[0023] According to another aspect of the present invention, there is provided a method of reproducing main data and additional data, the method comprising: providing the additional data associated with the main data, the additional data being divided into a plurality of segment units; and reproducing the additional data in a synchronous manner to the main data using time information if indication information indicates a presence of the time information, wherein the time information is present only if the indication information indicates that the time information is present, wherein the main data and the additional data are reproduced according to link information for linking the main data and the additional data, and wherein the link information is separated stored from the main data and the additional data.
[0024] According to another aspect of the present invention, there is provided a method of providing additional data to be reproduced with main data, the method comprising: providing the additional data associated with the main data, the additional data being divided into a plurality of segment units and capable of being reproduced with the main data in a synchronous manner; and providing management data associated with the additional data, wherein the management information includes link information for linking the main data and the additional data, time information for reproducing the additional data with the main data in the synchronous manner, and attribute information for providing at least one attribute of the additional data.
[0025] According to another aspect of the present invention, there is provided a method of providing additional data to be reproduced with main data, the method comprising: providing the additional data associated with the main data, the additional data being divided into a plurality of segment units and capable of being reproduced with the main data in a synchronous manner; and providing management data associated with the additional data, wherein the management information includes time information and indication information indicating a presence of the time information, the time information being present only if the indicating information indicates the time information is present, wherein the management information further includes linking information for linking the main data and the additional data, and wherein the additional data is provided separately from the main data.
[0026] These and other objects of the present application will become more readily apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The accompanying drawings, which are included to provide a further understanding of the invention, illustrate the preferred embodiments of the invention, and together with the description, serve to explain the principles of the present invention.
[0028] In the drawings:
[0029] FIG. 1 is a block diagram of an optical disk device that records/reproduces audio data to/from a recording medium according to a related art;
[0030] FIG. 2 shows the structure of RTR_AMG (Real Time Record Audio ManaGement) recorded as navigation data on a rewritable disk according to a related art;
[0031] FIG. 3 shows an RTR_AMG in which TXTDT_MG (TeXT DaTa ManaGer) structured according to an embodiment of the present invention;
[0032] FIG. 4 shows CI (Cell Information) structured according to an embodiment of the present invention;
[0033] FIG. 5 illustrates an example of a continuous and synchronous display of a series of lyric segments together with reproduced audio data audio according to an embodiment of the present invention;
[0034] FIG. 6 shows an RTR_AMG structured according to another embodiment of the present invention; and
[0035] FIG. 7 shows ALFIT (Audio Lyric File Information Table) structured according to another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0036] In order that the invention may be fully understood, preferred embodiments thereof will now be described with reference to the accompanying drawings.
[0037] In an audio data recording method in accordance with an embodiment of the present invention, lyric or user data related with a song recorded on a rewritable disk such as DVD-RW is segmented into several units. Each segmented unit is linked with each corresponding part of the recorded song through segment synchronizing information for the purpose of minute synchronization of song and additional data.
[0038] FIG. 3 shows an RTR_AMG in which TXTDT_MG structured according to an embodiment of the present invention is included.
[0039] As shown in FIG. 3 , RTR_AMG is composed of RTR_AMGI, AUDFIT, ASVFIT, ORG_PGCI, UD_PGCIT, TXTDT_MG, and MNFIT. The TXTDT_MG in FIG. 3 is composed of respective ALUI (Audio Lyric Unit Information) search pointers and corresponding pieces of ALUI. Each ALUI includes lyric segments ‘SG_L_TXT #i’, which is segmented lyric text, and their individual output-time related information ‘Time #i’.
[0040] The output-time related information ‘Time #i’ is time-length, which a corresponding lyric segment is kept displayed for, or instant time when a corresponding lyric segment starts to be displayed. The lyric text may be displayed as subtitles. This time information is also used to differentiate a linked lyric segment from several lyric segments displayed altogether by different color or font for a specified duration.
[0041] Each lyric segment includes an ID code ‘IDCD’ as shown in FIG. 3 . The ID code is used to indicate that each segmented unit has output-time related information, that each segmented unit includes lyric or user data, or that the output-time related information is duration or start time.
[0042] Each group of segmented units is linked with a recorded song through each ALUI search pointer in TXTDT_MG as shown in FIG. 3 . For example, an ALUI search pointer linked with a recorded song points a start position of the first lyric segment of an associated segment group.
[0043] To link a recorded song with an ALUI search pointer, a piece of CI (Cell Information) related with an AOB (Audio OBject), which corresponds to a single recorded song in general, is structured in the ORG_PGCI as shown in FIG. 4 .
[0044] Each CI includes an AOBI_SRPN (AOB Information SeaRch Pointer Number) for indexing information location of a related AOB (or song), an ASVUI_SRNP (ASVU (Audio Still Video Unit) Information SeaRch Pointer Number) for indexing information location of still video data linked with an AOB, and an ALUI search pointer number ‘ALUI_SRPN’ for indexing an ALUI search pointer in the TXTDT_MG that points a segment group containing a full lyric text related with an AOB.
[0045] Thus, if a song, namely, an AOB is chosen, the controller 14 reads the number written in ALUI_SPRN of CI associated with the selected AOB, and reads an address in ALUI search pointer indexed by the read number in the TXTDT_MG. The location of lyric text related with the selected song is found by this read address.
[0046] Then, lyric segments are retrieved sequentially from the addressed location by the reproduced signal processor 12 . At this time, the controller 14 examines an ID code preceding each lyric segment. If the ID code is indicative of type of output-time related information, e.g., a time length for which the following lyric segment ‘SG_L_TXT #i’ is displayed, the controller 14 keeps outputting each lyric segment for a duration specified by the time length and changes current lyric segment with the next one after the time length expires. This operation continues until the end of AOB or stop request is received.
[0047] FIG. 5 illustrates continuous and synchronous display of a series of lyric segments together with reproduced audio data belonging to the selected AOB.
[0048] Referring to FIG. 5 , if the ID code is indicative of presentation start time of each lyric segment, the controller 14 outputs each lyric segment the moment an elapsed time after reproducing the chosen AOB (or song) becomes equal to the start time specified by field ‘Time’. The currently-outputted lyric segment keeps being outputted until the next segment is outputted at its start time.
[0049] If the ID code is indicative of not the type of output-time related information but the type of additional information, e.g., user data, the controller 14 processes the segmented additional information adequately for the designated type.
[0050] If the ID code indicates that there is no output-time related information in lyric segments, then the lyric segments are sequentially read out irrespective of time. This operation seems to correspond to a conventional lyric data displaying method.
[0051] The lyric segments related with a recorded song may be written in a file other than the RTR_AMG, instead of the TXTDT_MG
[0052] FIG. 6 shows an RTR_AMG structure according to another embodiment of the present invention. The RTR_AMG of FIG. 6 includes an ALFIT (Audio Lyric File Information Table) for storing in another file the lyric data that are composed of segmented information such as lyrics or user data of all recorded songs.
[0053] FIG. 7 shows the structure of the ALFIT of FIG. 6 . The ALFIT is composed of ALFITI (ALFIT Information) and ALFI. The ALFITI includes fields of ‘ALFI_Ns’ reserved for the number of audio lyric information files, ‘AL_I_Ns’ for the number of pieces of audio lyric information, and ‘ALFIT_EA’ for an end address of ALFIT.
[0054] The ALFI is composed of ALFI_GI (ALFI General Information) and a plurality of ALUI (Audio Lyric Unit Information) search pointers, each including ‘ALU_SA’ for a start address of a lyric unit, ‘ALU_SZ’ for size of a lyric unit, and ‘L_ATR’ for attribute of a lyric.
[0055] The ALU_SA in each ALUI search pointer points to the location of a corresponding ALU (Audio Lyric Unit) in a lyric file named by ‘AR_Lyric.ARO’ that is not included in the RTR_AMG. Each ALU in the lyric file ‘AR_Lyric.ARO’ includes a lyric text associated with a single recorded song, and the lyric text is divided into several segments ‘SG_L_TXT #i’. Each lyric segment also has output-time related information ‘Time’ and ID code ‘IDCD as described in the aforementioned embodiment.
[0056] According to this structure of the RTR_AMG, the ALUI_search pointer number contained in CI indexes an ALUI search pointer pointing to a lyric unit in the file ‘AR_Lyric.ARO’ associated with a recorded AOB, namely a song.
[0057] Thus, if a song, namely, an AOB is chosen, the controller 14 reads the number written in ALUI_SPRN of CI associated with the selected AOB, and reads an address in ALUI search pointer contained in the field ‘ALFI’ indexed by the read number. The location of a lyric unit related with the selected song is found in the file ‘AR_Lyric.ARO’ by this read address.
[0058] Then, lyric segments are retrieved sequentially from the first segment ‘SG_L_TXT # 1 ’ at the addressed location in the file ‘AR_Lyric.ARO’ by the reproduced signal processor 12 . At this time, the controller 14 examines an ID code preceding each lyric segment.
[0059] If the ID code is indicative of the type of output-time related information, the controller 14 conducts continuous and synchronous display of a series of lyric segments together with reproduced audio data belonging to the selected AOB. In this lyric synchronous display operation, a just-displayed lyric segment can be differentiated by color or font from neighboring lyric segments displayed altogether.
[0060] The above-explained lyric data synchronizing method ensures minutely-synchronous lyric presentation with audio data, e.g., song being reproduced in real time from a rewritable recording medium. Thus, a user is able to enjoy a reproduced song better through the lyric text displayed in synchronization with the song.
[0061] The detailed description of the invention has been directed to certain exemplary embodiments, various modifications of these embodiments, as well as alternative embodiments, will be suggested to those skilled in the art. The invention encompasses any modifications or alternative embodiments that fall within the scope of the claims.
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A recording medium, method and apparatus for managing data are discussed. According to an embodiment, the present invention provides a method of reproducing main data and additional data. The method includes receiving the additional data associated with the main data, the additional data being divided into a plurality of segment units; and reproducing the additional data in a synchronous manner with the main data using time information if indication information indicates a presence of the time information. The time information indicates a presentation time of the additional data with respect to the main data. The main data and the additional data are reproduced according to management data, the management data including link information for linking the main data and the additional data.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon, claims the benefit of priority of, and incorporates by reference, the contents of Japanese Patent Applications No. 2002-110296 filed Apr. 12, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a starter motor for starting internal combustion engines, and particularly to an improved magnet switch for use in such a starter motor.
[0004] 2. Description of the Related Art
[0005] There is a need for a variety of improvements in starter motors to reduce harmful impacts on the environment. For example, engine starter motors should be lighter and more compact, and have greater durability to maintain or withstand frequent engine idling stops (what is called “eco-run”). Japanese Patent Laid-Open Publication No. Hei 9-68142 discloses a technique that reduces damage on the involved gears by ensuring enhanced gear engagement and lowering the current in the switch in order to reduce the size of the switch itself. More specifically, the current in the attraction switch has been reduced by more than 70%, the attraction coil has been downsized significantly, the ON and OFF switching of the main current and engagement with the ring gear of the pinion are performed with a plunger situated through the center of the coil, a rod moves together with the plunger shaft, and a movable contact and a hook are used for starting the engine. Some of the switches move the movable contact and the hook independently of the two separate rods, but because they move somewhat simultaneously while driven by an attraction force, the operation mechanism is common.
[0006] Although the improved engagement made the switch smaller, the electronic current that intermittently runs in the contact thereof does not change because it is determined by the necessary motor power. Consequently, since the current of the same magnitude runs the switch contact, the current density increases, and the contact is likely to wear at an anomalous rate. Moreover, since a thin rod must hold the contact and the hook (joint) at each end, the weight ratio of the contact and the hook grows, and the rod operation is affected by an increased load from the relatively heavy contact and hook. In addition, the sliding gap between the plunger and the inner circumference of the coil leads to instability in operation and results in such problems.
[0007] Meanwhile, although the thin rod (its diameter is approximately 2 mm) has to hold a small contact via an insulator washer for electric isolation, the insulator washer of poor mechanical strength often breaks during operation. In general, a contact current of about 700 A runs in the contact. Thus such a break-up of the insulator causes an absence of a safety gap, because the thickness of the insulator is 1 mm or less. Further, when the shock of the pinion engagement reaches the plunger and the contact via the hook, the thin, small rod contact and insulator are likely to break. To solve such problems, the contact may be maintained as large as before. However, this makes the thin rod have a large contact, and its operation becomes unstable. Specifically, the contact chatter by ON and OFF switching produces electric arks and may fuse the contact. Furthermore, as long as the rod exists inside the plunger, the saving of copper used in the coil is limited.
[0008] Since the plunger has key components (contact and hook) at both ends, both ends of the rod must be disposed outside the switch through the attraction coil thereof. Then the rod must be made of a non-magnetic material to utilize the magnet force of the coil. This non-magnetic material is usually an expensive material such as stainless steel or copper, which results in an expensive switch. Because the plunger must be assembled from the magnetic and non-magnetic parts in the small space in the attraction coil, the production cost becomes higher. If the rod is made of a magnetic material, all the magnetic flux runs in the rod, and the air gap does not have a magnetic flux. Then, no force to decrease the air gap is produced and the switch does not work.
SUMMARY OF THE INVENTION
[0009] To solve the above problems, an object of the present invention is to provide an inexpensive, reliable, compact switch which does not require special materials. The switch will not have a rod running through the plunger and fixed iron core while the contact and the hook are moved, not inside, but outside the attraction coil to reduce the size of the coil and maintain a sufficiently large contact.
[0010] In the magnet switch according to a first aspect of the present invention, the attraction coil has a plunger alone in its center, and this plunger is allowed to slide toward the side opposite to a fixed iron core. Thus it becomes possible to eliminate the non-magnetic rod from penetrating the fixed iron core, and the entire structure that forms a magnetic circuit can be made of iron. As a result, the inner circumference of the coil can be made small, and the plunger can also be made thin at no additional cost. Because the contact and the hook are formed on a thick plunger, instead of a thin rod, and the sliding gap between the rod and the plunger or fixed iron core becomes unnecessary, the operation of the contact is stable.
[0011] In the magnet switch according to a second aspect of the invention, the contact for current ON and OFF control is formed at one end of the switch, while the joint that drives the pinion is formed at the other end thereof, and they are connected to each other by a flange formed on the outer periphery of the case. Unlike the conventional thin rod, this flange interferes with nothing, so it can be made thick to be sufficiently strong. Then the flange can be large enough in terms of electrical and mechanical requirements with no need to enlarge the switch including an attraction coil and other parts.
[0012] In the magnet switch according to a third aspect of the invention, the contact holder is fixed via the flange arm extending from the outer periphery of the case. Thus even a large contact can be fixed with the holder from the outer periphery with a sufficient margin. If the holder is made of an electric insulator, the mechanical strength can be held high and the contact can securely work.
[0013] In the magnet switch according to a fourth aspect of the invention, the switch itself is firmly fixed in the starter, and the sliding unit such as the joint and the flange are covered with a cover that covers the contact room. Thus there is no need to add a separate dust cover or enlarge the outer diameter of the switch. Specifically, if the switch of the invention is installed in a usual starter, a separate large cover becomes necessary and its outer diameter becomes as large as the conventional switch. However, the structure of the invention is free from such drawbacks and is compact and durable against dust and water.
[0014] The magnet switch according to a fifth aspect of the invention is highly reliable and can be reduced in size. Engagement control makes the attraction coil current significantly small and permits a reduction in the size of the switch, while reducing production costs.
[0015] In the magnet switch according to a sixth aspect of the invention, the center of the attraction coil is made of a fixed iron core alone, and any non-magnetic rod penetrating the fixed iron core is not necessary. Additionally, all the parts can be made of iron to form a magnetic circuit. Thus, the inner circumference of the coil can be made thin, and as a result, the attraction coil can be made small and there is no substantial increase in costs. Because the contact and the hook are formed on a thick plunger, instead of a thin rod, and no sliding gap exists between the rod and the plunger or the fixed iron core, the operation of the contact is not affected. Moreover, since the magnetic circuit of the sliding unit of the plunger and case sidewalls is not the inner circumference of the case sidewalls as in a conventional case, but rather the outer circumference, the operation area becomes large, and accordingly the magnetic resistance becomes smaller. Because of this, the coil can be made smaller.
[0016] In the magnet switch according to a seventh aspect of the invention, the contact for current ON and OFF control is formed at one end of the switch, while the joint that drives the pinion is formed at the other end thereof, and they are connected to each other by a flange formed on the outer periphery of the case. Unlike the conventional thin rod, this flange interferes with nothing, therefore it can be made thick to be sufficiently strong. Then the flange can be large enough in terms of electrical and mechanical requirements with no need to enlarge the switch including an attraction coil and other parts.
[0017] In the magnet switch according to an eighth aspect of the invention, the contact holder is fixed via the flange arm extending from the outer periphery of the case. Thus even a large contact can be fixed with the holder from the outer periphery with a sufficient margin. If the holder is made of an electric insulator, the mechanical strength can be held high and the contact can securely work.
[0018] In the magnet switch according to a ninth aspect of the invention, the switch itself is firmly fixed in the starter, and the sliding unit, that is, the joint and the flange, are covered with a cover covering the contact room. Thus there is no need to add a separate dust cover or enlarge the outer diameter of the switch. Specifically, if the switch of the invention is installed in a usual starter, a separate large cover becomes necessary and its outer diameter becomes as large as the conventional switch. However, the structure of the invention is free from such drawbacks, is compact and durable against dust and water.
[0019] The magnet switch according to a tenth aspect of the invention is highly reliable, small in size, and can be made at a reduced cost. Engagement control makes the attraction coil current significantly small, which permits a reduction of the switch size.
[0020] Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
[0022] [0022]FIG. 1 is a cross-sectional view of the starter of a first embodiment of the invention;
[0023] [0023]FIG. 2 is a cross-sectional view of the switch of FIG. 1;
[0024] [0024]FIG. 3 is an enlarged diagram of the movable portion of the switch of FIG. 1;
[0025] [0025]FIG. 4 is a cross-sectional view of the switch of a second embodiment of the invention; and
[0026] [0026]FIG. 5 is a partial cross-sectional view of the starter where the switch of FIG. 4 is installed.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] Now the starter switch of the invention will be described with reference to a first embodiment shown in FIGS. 1, 2 and 3 .
[0028] A switch 50 has an attraction coil 51 that generates electromagnetic force, a plunger 52 that forms a magnetic circuit, a case 55 , a fixed iron core 54 , and an air gap 56 between the plunger 52 and the fixed iron core 54 . The case 55 includes a cylindrical part 55 a and side walls 55 b , 55 c , constituting the fixed part of the switch covering the attraction coil 51 together with the fixed iron core 54 . The cylindrical part 55 a , side walls 55 b , 55 c of the case 55 , and the fixed iron core 54 may be either separated or integrated, as long as they can form a magnetic circuit (in the figure, the side wall 55 b and fixed iron core 54 are made in one piece).
[0029] A first contact 70 is composed of a fixed contact 71 and a movable contact 72 . The movable contact 72 forms part of a first elastic body 73 made of a conductive, mechanically strong material such as phosphor bronze.
[0030] A second contact 80 is composed of a fixed contact 81 and a movable contact 82 . The first and second contacts 70 , 80 form a parallel circuit between the battery and the motor. The fixed contact 71 of the first contact 70 made of carbon functions as a resistor in the circuit. The movable contacts 72 , 82 are provided with contact pressure against the fixed contacts 71 , 81 respectively, by the first and second elastic bodies 73 , 83 (two pieces in the figure). In the present embodiment, the elastic bodies 73 , 83 are installed in the movable unit that moves together with the plunger. However, they may be installed on the fixed contact 71 , 81 sides or installed in a cross. The first fixed contact 71 is connected to a battery via the holder 62 , while the second fixed contact 81 is connected to the battery (not shown) directly with a terminal 60 .
[0031] At one end of the plunger 52 , a flange 53 and a joint 53 a are fixed. An arm 53 b of the flange 53 is connected to a holder 58 via the second elastic body 83 . At the end of the holder 58 , the movable contacts 72 , 82 are fixed by an appropriate method such as a press fit by simply pushing the movable contacts 72 , 82 . Thus when the plunger 52 moves, the flange 53 , holder 58 , movable contacts 72 , 82 also move almost together to work as a switch as a whole.
[0032] The joint 53 a has a hole where an end of a connection means 90 is to be inserted. The other end of the connection means 90 is to restrict the rotation of the pinion 25 via a component 91 . Specifically, when the attraction coil 51 works to pull the plunger 52 , the air gap 56 becomes shorter, and the component 91 contacts, via the connection means, the pinion 25 to restrict its rotation. When the motor is activated under this condition, the pinion 25 moves in the axial direction guided by helical splines 20 a , 25 a formed in the outer periphery of the output shaft 20 and the inner circumference of the pinion 25 , respectively, and then engages with the ring gear (not shown) of the engine. The shaft 11 of the motor armature 10 is connected to the output shaft 20 via a gear reduction mechanism 30 and a clutch 27 .
[0033] A return spring 57 pulls the plunger 52 back to its original position when the attraction coil 51 is deactivated. In the present embodiment, the return spring 57 is inserted in the plunger 52 , which housed in the magnet switch 50 . However, it may be placed anywhere as long as it causes the return of the plunger 52 to its original position. The inner circumference of the attraction coil 51 can be a bearing for the sliding plunger if a sleeve (not shown) made of a thin metal plate (for example, copper) is inserted therein.
[0034] A plate spring band 95 fastens the switch onto a seat 96 , covering the cylindrical part 55 a of the case 55 with its elasticity. A cover 98 covers the switch 50 and the contacts 71 , 81 .
[0035] Now the operation of the present invention will be described. When the key switch of the vehicle (not shown) is turned ON, the attraction coil 51 exerts an electromagnetic force to the plunger 52 so that it moves against the return spring 57 to shorten the air gap 56 . Then, this motion via the connection means 90 restricts the rotation of the pinion 25 . Next, as the first contact 70 connects to the resistor 91 (the carbon-based fixed contact 71 also serves as a resistor in the embodiment), the motor rotates very slowly. Then, while the output shaft 20 rotates, the rotation of the pinion 25 is restricted, and the pinion 25 . moves along the axial direction guided by the splines 20 a , 25 a , and engages with the ring gear (not shown).
[0036] When the plunger 52 moves further, the second contact 80 is closed. Since the first and second contacts form a parallel circuit and the first contact 70 has a resistor, the electric current runs dominantly in the second contact circuit and the motor works to activate the engine. Meanwhile, when the engine has been activated and the key switch has been turned OFF, the attraction coil 51 loses electromagnetic force. Then, the elastic force of the return spring 57 pulls the plunger 52 back, and the second contact 80 is opened. Then a current limited by the resistor 90 is provided to the motor. When the plunger 52 is pulled back further, the first contact 70 is also opened. Because the operations of the engaging parts other than the switch are similar to those disclosed in Japanese Patent Laid-Open Publication No. Hei 10-115274, their explanation is not repeated here.
[0037] Because the present invention has no rod penetrating through the attraction coil in the axial direction, the plunger can be made thin and the coil can be made small. The switch has a substantially cylindrical shape with a bottom, and has a structure where the contact and joint move together with the plunger in one end of the switch. As a result, the rod can be eliminated in the sliding gap, and the mechanical structure becomes stable with less play. Since the contact is fastened, with its outer circumference being fixed by the outer periphery of the switch, the holder may have sufficiently large dimensions and therefore its mechanical strength can be ensured even when the holder is made of a resin. Overall, the switch is compact. Furthermore, the sliding part works also as the switch cover, eliminating additional components. Then, combined with the engaging mechanism of the pinion rotation restricting method, the present invention can provide a compact, reliable starter at a low cost. Although a two-stage operation using two contacts is described in this embodiment, this invention can be applied to one-stage operation type switches having a single contact.
[0038] (Second Embodiment)
[0039] Next, a second embodiment will be described below with reference to FIGS. 4 and 5. The fixed iron core 54 has sidewalls 55 b , 55 c on its side faces, and in combination with the cylindrical part 55 a of the case they form a fixed part of the magnetic circuit for the switch. The plunger 52 has a cylindrical shape and a flange 53 at one end and an arm 53 b at the other end in one piece. The plunger 52 is pulled by the magnetic force of the attraction coil 51 and shortens the air gap 56 so as to close the contact and cause engagement with the pinion. A return spring 57 and an elastic body 83 provide contact pressure. The other parts and their operations are the same as those of the first embodiment, so their explanation is not repeated here. The present invention can thereby provide a reliable, compact switch at a low cost.
[0040] The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.
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A magnet switch has a coil of a reduced size and a sufficiently large contact and does not have a rod running through the plunger or the fixed iron core. A flange and a joint are fixed at one end of the plunger. The arm of the flange is connected to a holder via an elastic body. Movable contacts are pushed into the holder to be fixed at one end thereof. When the plunger moves, the flange, the holder, and the movable contacts move somewhat simultaneously to work as a switch.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
[0002] Not Applicable
BACKGROUND OF THE INVENTION
[0003] The present invention relates to the field of radar imaging methods. More specifically, the present invention relates to a system and method for radar image rendering.
[0004] Enhanced vision systems are vital in the control of aircraft, especially during take off approach, and landing in adverse conditions. Radar and Electro-Optical Infra-Red (EO/IR) systems are frequently relied upon to provide these capabilities. The effectiveness of these systems greatly depends on the quality of their imaging technology.
[0005] Imaging techniques are well known and widely used in the art. Certain imaging technologies are better suited for certain applications. For example, radar imagery is widely used for navigation, surveillance, and reconnaissance, as well as target tracking and identification.
[0006] Radar imagery is conventionally accomplished by a two-dimensional scan (range and azimuth). An image is rendered from the amplitude of the reflected signals from each resolution cell (azimuth beam width, or step by range resolution length or range step) by assuming all returns are from a flat plane, which allows transforming from range/azimuth coordinates into a level X, Y Cartesian frame. The resulting image is a plan view with image intensity, grey scale shading, color or some combination thereof, in each basic resolution cell related to the radar return level. These images created from a top down perspective are useful in many applications, but suffer from several shortcomings when a view from a different perspective is required, such as, for example, from a pilot's perspective.
[0007] Conventional radar imaging systems do not provide all three coordinate dimensions (there is no elevation angle measurement) of the location of the basic resolution cell to enable the transformation of data (i.e., the image) to another perspective. Thus, they do not present objects at the proper height in the image, from the pilot's perspective.
[0008] Some of the current state of the art radar image rendering systems use databases for vertical information. In such systems, the radar sensor location is determined by a precise navigation system, and the two-dimensional image generated, as described above, is registered in absolute coordinates, enabling the use of height data from the database. This approach suffers primarily in two respects: First, there is no capability of detecting objects with a vertical dimension not stored in the database, such as construction towers erected since the database was last updated. Second, the required resolution for some applications is not available, such as is the case when a helicopter is landing in a dust cloud or fog, where a resolution on the order of one foot (30 cm) is required to assure the pilot's situational awareness.
[0009] Another shortcoming in the current state of the art in radar imaging is the irregular amplitude of returns from visually uniform surfaces due to a phenomenon known as “specular reflection.” Radar imagery traditionally employs relatively long wavelengths of reflected energy (no radiated waves), causing unnatural bright and dim areas in an image of a surface that would appear uniform to the human eye. Since the human eye is accustomed to receiving both radiated and reflected energy from detected surfaces, the reconstructed radar image seems unnatural.
[0010] The current state of the art in radar imaging is unable to provide angular resolution comparable with EO/IR sensors. This lack of resolution causes a very grainy image in the azimuth dimension which, when coupled with the specular reflection characteristics, makes human interpretation of most radar images difficult.
[0011] There is thus a need in the art for an improved system or method to provide images with better resolution, and to present them from a pilot's perspective rather than the radar location.
SUMMARY OF THE INVENTION
[0012] The aforementioned need in the art is addressed by a novel three-dimensional (3D) radar image rendering system and method in accordance with the present invention. (Rendering is the process of generating an image from a model, by means of a software program. In the present application, the model is the description of three-dimensional objects, while the generated image is displayed on 2D computer graphics terminal). The invention provides significant improvement in the usability of airborne radar imaging systems. The illustrated embodiment optimally blends the data acquisition method and rendering techniques to provide pilot-centered, easily interpretable radar images.
[0013] Broadly, the radar imaging system of the present invention employs a 3D radar scan (range, azimuth, and elevation) for the direct measurement of the location of a surface cell (the range of the return for each step in the angle scan), and for the direct measurement of the amplitude of the return from each cell. The availability of all three dimensions for each point allows the transformation of all data into a Cartesian frame (an X, Y horizontal plane and a Z vertical dimension). The X, Y coordinates of all cells causing returns are connected by lines forming triangles by a known triangulation algorithm, thereby creating a 3D “mesh” of triangles describing the detected surface.
[0014] Grey scale shading and/or coloring of the triangular surfaces is then added, based on the radar-determined geometry of the three vertices of each triangle (Z coordinate value or range from a selected a point, for example). The intensity of the grey scale shading or coloring is based on radar return signal amplitude. The result is a simulated or “rendered” 3D surface (on a 2D display) comprising an arrangement of colored and/or shaded triangles approximating the detected surface, with each color or grey scale shading value being a function of radar return amplitude.
[0015] In some applications, it may be desired to weight the triangle color or shading based on the distance from a desired perspective, thereby to enhance depth perception and ridgeline detection. A commercially available software package is then used to transform the 3D surface to the desired perspective (e.g., the pilot's seat, looking in the direction of the fuselage reference line).
[0016] The data acquisition relies on real time scanning and measurement of the terrain to get accurate information of the topology. This scanning and measurement technique combines radar and navigational data to locate and map vertical obstacles in the target area. The employed graphic animation process allows the presenting of the reconstructed image from a desired perspective, which, in the most cases, is the pilot's perspective. Viewing a terrain from the pilot's perspective allows the easiest interpretation of the presented images. The rendering technique employed by the system further enhances usability of the system by providing life-like 3D images. The enhanced image quality is partially derived from more detailed and accurate vertical information. The result is a more natural image, thereby facilitating human interpretation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIGS. 1A and 1B depict an aircraft equipped with a radar which scans a field of view to collect terrain data;
[0018] FIGS. 2A and 2B show exploded views of the region illuminated by a single step in the radar scan (one beam position);
[0019] FIG. 3 is an architectural block diagram of an airborne of 3D radar image rendering system in accordance with the present invention;
[0020] FIG. 4 is a flow diagram showing major functional/processing blocks of an airborne 3D radar image rendering system in accordance with the present invention,
[0021] FIG. 5 shows an X, Y “mesh” of triangles formed by lines describing a detected surface;
[0022] FIGS. 6 and 7 show two 3D meshes of triangles of the same surface from different perspectives;
[0023] FIG. 8A shows a wireframe image of a surface on a video display;
[0024] FIG. 8B shows a rendered image of the same surface as FIG. 7 with triangles filled in, based on geometry only;
[0025] FIG. 8C shows a rendered image of the same surface as FIG. 8B with triangles filled in, based on geometry and radar amplitude; and
[0026] FIG. 8D shows a rendered image of same surface as FIG. 8C in monochrome
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] The radar imaging system described herein employs a three-dimensional (3D) radar scan having range, azimuth, and elevation data components. Data are obtained by direct measurement of a location of a surface cell, range of return for each step in the angle scan, and amplitude of the return from the cell. The availability of all three dimensions for each point allows the transforming of all data into a Cartesian frame (X, Y horizontal plane coordinates, Z vertical coordinate). The X, Y coordinates of all cells causing returns are connected by lines to form triangles, thereby creating a 3D “mesh” of triangles (using prior art techniques) that describe the detected surface, as shown in FIGS. 5-7 .
[0028] As described above briefly, the detected surface model comprises an arrangement or “mesh” of contiguous triangular areas, the edges of which are straight lines. By using straight lines on the display device to connect the vertices of the triangles for which the position uncertainty is derived primarily from the radar beam width, there is an apparent improvement in resolution as compared to, for example, a mosaic of overlapping circles corresponding to the radar beam width. This effect primarily influences the horizontal dimension, since range resolution effects provide improved vertical resolution.
[0029] During a rendering process, grey-scale shading or coloring of the triangular surfaces is added, based on information extracted from the 3D location of each vertex (such as height, range, slope, etc.). A conventional 2D (X, Y or horizontal image plane) radar image is also formed by projecting all return amplitudes into the image plane. The 2D return amplitude data are used to create a texture map that modulates the intensity of the triangular surface grey scale or color, thereby capturing the additional information from the multiple range resolution cells within a single triangle. The resulting image has three key characteristics: an overall (outline) shape generated from the triangles based on the radar-measured terrain geometry; the color or grey scale shading of the individual triangular areas based on parameters extracted from the position of the three vertices defining each triangle; and the intensity of the grey scale shading or the coloring of each triangle based on return radar signal amplitude. In some applications, weighting the triangle (grey-scale or color) based on distance from a desired perspective point can be used to enhance depth perception and ridgeline detection. A commercially available software package is then used to transform the 3D image to the desired perspective (e.g., from the pilot's seat, looking in the direction of the fuselage reference line).
[0030] The foregoing 3D radar image rendering method provides imagery based on real time measured elevation angles from the pilot's perspective, thereby assuring that the elevation angle appears correct in the recently created image. The vertical resolution of the radar imagery is determined by radar range resolution, as opposed to radar elevation angle resolution, with the resulting vertical positioning being based on real time direct angle measurement. The use of geometry variables from the image perspective point helps to minimize the effect of the reflected power from uniform surfaces, thus facilitating the mimicking of human visualizations, which rely on radiated power as well as reflected power.
[0031] FIGS. 1A. 1B , 2 A, and 2 B show an operating environment of a 3D radar image rendering system. An aircraft 10 is equipped with a radar transceiver system R ( FIG. 1B ) that transmits a radar beam 12 that scans a field of view relative to an image plane 16 having a U-dimension 14 and a V-dimension 15 . The field of view is defined by an azimuth scan angle 11 and an elevation scan angle 21 . The transmitted radar beam 12 has a beam width that is narrower than both the azimuth scan angle 11 and the elevation scan angle 21 . The transceiver R receives radar return signals in a range that is proportional to the radar reflectivity of objects (such as a vertical obstacle 13 and terrain surface 22 ) illuminated within the beam 12 for each range resolution cell 26 ( FIG. 2A ) defined within an illuminated terrain area 17 having a terrain return 23 ( FIGS. 1B , 2 B). In FIG. 1A , the regions potentially illuminated by the beam 12 are indicated by the numeral 18 , with the region shadowed by the vertical obstacle 13 being indicated by the numeral 19 . In general few range resolution cells will contain non-zero returns because there are no objects immediately below the aircraft 10 , and no returns are received at ranges greater than the range to the terrain surface 22 (no reflections from below the terrain surface 22 ).
[0032] FIGS. 2A and 2B show exploded views of the area 17 illuminated by a single beam position, illustrating the multiple amplitude samples at several ranges. For each antenna position, a single range to the terrain or obstacle is estimated, or a single point is determined. A single point is defined by an elevation angle with an elevation resolution 24 , an azimuth angle with an azimuth resolution 25 , and a range estimate 27 consisting of a single selected range resolution cell 26 .
[0033] FIG. 3 shows the major functional/processing modules of an image rendering system 100 in accordance with a preferred embodiment of the present invention. The rendering system 100 includes four functional subsystems: a radar signal processing subsystem 101 ; a terrain geometry processing subsystem 102 ; a terrain image processing subsystem 103 ; and a graphics library subsystem 104 .
[0034] The radar signal processing subsystem 101 performs radar signal processing and data reduction. This processing involves frequency diversity employed to reduce the variation in return signal amplitude from a uniform surface, the selection of large amplitude return signals, and range decimation to reduce the quantity of data. The raw radar return signal amplitudes from transmissions made at different frequencies are first averaged over a time period equal to the time the antenna beam position dwells in one angular step, and the resultant averaged return in each range resolution cell is processed to ignore those range bins containing negligible return amplitudes. The data are further compressed by combining amplitudes over multiple range bins under low grazing angle conditions (long range and low elevation angles). This operation is referred to as range decimation. The decimated averaged range samples are applied to the terrain geometry processing subsystem 102 and the terrain image processing subsystem 103 .
[0035] The terrain geometry processing subsystem 102 calculates terrain geometry. The terrain geometry processing subsystem 102 generates two basic outputs: a 3D mesh of triangles characterizing the terrain surface topology within the radar field of view; and a list of obstacles (points) detected above the terrain surface.
[0036] The radar data is input as amplitude versus time for each angle step (azimuth and elevation) in the raster scan of the field of view. Ignoring noise and returns through antenna side lobes, for each angle step, where the terrain is illuminated by the radar beam, non-zero returns will be received over a range interval. For beam directions not pointing towards the ground (i.e., the terrain surface 22 ), no ground return is received, but returns from obstacles (e.g. the vertical obstacle 13 ) above the terrain surface may be received. The coordinates of each terrain surface point detected during the scan period are defined in a level plane to enable the graphics tool to apply texturing, and a “vertex list,” comprising the coordinates of each detected point and an associated ID number, is constructed. Each resolution cell within the level plane can have only one terrain point (overhanging cliffs and the like are ignored). The lowest point above the level plane detected is declared a terrain point, and any other points with higher elevation values are declared obstacle points and entered on an “Obstacle list”. Entries in the vertex list (terrain points) are input to a triangulation algorithm, which operates on the horizontal coordinates of the points by forming triangles using the well-known principles of “Delaunay” or “Delauney” triangulation. The output of the triangulation algorithm is a list of triples from the vertex list identifying the three vertices of each triangle.
[0037] The terrain image processing subsystem 103 generates terrain image intensity maps. The terrain image path generates a 3D radar image based on the amplitude of radar returns.
[0038] The graphics library subsystem 104 is a commercially available graphics library software package, such as, for example, the OpenGL interactive 3D and 3D graphics application programming interface available from Seaweed Systems, Inc. of Burlington, Mass. (www.seaweed.com). It accepts a 3D mesh of triangles defining a surface geometry (the triangle and vertex lists), color and/or grey scale values for the vertices (the information extracted from the 3D location of each vertex), a texture map defining intensities for the triangular areas (the 3D amplitude-based texture map), and a position and look direction, defining an image perspective. The graphics library 104 takes these inputs typically at the rate of one per second. Then it colors or shades the terrain geometry model surfaces by blending or smoothing the vertex values across the triangular surface area, and it adjusts display intensity per the intensity map (variations in both color or grey scale and intensity within each triangular facet). Intensity is based on radar return signal amplitude. In addition, points and/or other shapes can be added anywhere in the image, a feature that is used to add obstacles (radar returns above the terrain surface) to the terrain image. The created terrain model image is presented from the desired perspective, typically the pilot reference position. The output image is updated at typically, tens of Hz to provide a current image from the moving platform.
[0039] The functions of the above-described functional subsystems 101 - 104 are implemented by several sub-function modules. The algorithms to implement each sub-function are not described, as they may be conventional algorithms that would be easily determined or devised by those of ordinary skill in the art. Accordingly only the sub-functions provided by the algorithms are identified by their respective modules. Each of the sub-functions is performed with a predetermined repetition rate. These rates are:
r 1 where the rate is defined by c/δR for pulsed radar (where “c” is speed of light and “δR” is the range resolution of the radar); r 2 where the rate is determined by the repetition period of the pulsed radar or the dwell time for frequency modulated continuous wave radar; r 3 where the rate is determined by the averaging update interval (several r 2 periods); r 4 where the rate is the volume scan rate; and r 5 where the rate is determined the display update rate.
[0045] Referring to FIG. 4 , the radar signal processing function 101 includes an analog-to-digital conversion module 105 , a data averaging module 106 , and a signal selection module 107 . The conversion module 105 converts the analog radar data to digital form for further processing. The processing rate is r 1 . The data averaging module 106 receives the digitized radar data from the conversion module 105 , and it performs data averaging of each angle step period. Averaging returns from individual resolution cells allows use of returns from differing radar frequencies (frequency diversity), which has the effect of reducing the variation in return amplitude from different areas of a uniform object. This method more closely replicates the passive energy collected by the human eye in forming an image. Averaging also compresses the number of data samples that must be processed, thereby reducing data rates and processor loading. Range decimation, described above, further reduces data rates and processor loading. The processing rate of this calculation is r 2. The signal selection module 107 selects the strongest return signal for further processing. The processing rate of this calculation is r 3.
[0046] The terrain geometry processing function 102 includes several sub-function modules, the first of which is a range estimation module 108 that performs range-to-terrain estimate calculations from the radar data received from the radar signal processing function 101 for each angle step, where the terrain is illuminated by the radar beam. The processing rate of this calculation is r 3.
[0047] A range filter module 109 combines estimated range values and predicted range values to arrive at the range, azimuth, and elevation coordinates of the point on the terrain surface toward which the radar beam is currently pointed. The estimated range data are obtained from the range estimation module 108 , while the predicted range values are obtained from a predicted range module 113 , described below. The processing rate of the range filter module 109 is r 3.
[0048] A transform to terrain model coordinates module 110 takes the radar data (azimuth, elevation, range), the aircraft position (latitude, longitude, altitude), and the aircraft attitude (heading, pitch, roll), and computes the three dimension X, Y, Z position in a terrain model coordinate system. This also includes projecting the X, Y, Z position coordinates onto the image plane to compute the texture map U, V “coordinates”. (The U, V “coordinates” are standard, normalized values allowing the graphics library 104 to register correctly the texture map onto the terrain surface.) The processing rate of this calculation is r 3.
[0049] A terrain test module 111 scans the set of 3D points to segregate a subset of points defining a geometric terrain (no points overhanging any other points)—the vertex list—from other points—the obstacle list—. The obstacle list is converted into a set of points and/or shapes for input to the graphics library 104 . The terrain test module 111 outputs the list of vertices and the obstacle data to the graphics library 104 .
[0050] Referring again to FIG. 2A , the expanded view of the region illuminated by a single beam position illustrates that, for practical radar parameters, the range resolution provides much better resolution than does the resolution imposed by either the azimuth or elevation antenna beams. Modulating the intensity of the terrain geometry model by mapping the texture map derived from radar amplitude data onto the surfaces provides a computationally efficient mechanism to retain the significant improvement in vertical resolution provided by the range resolution, as opposed to that provided by the elevation beam width. The multiple range cells within each beam position can be thought of as a means to interpolate within a single elevation beam sample. FIG. 2B shows the region where the main beam intercepts the ground. The fine lines within the antenna beam width represent the improvement in vertical resolution. The processing rate of this calculation is r 4 .
[0051] Referring again to FIG. 4 , a 3D triangulation module 112 is a real-time implementation of an algorithm published in the open literature and well-known to those of ordinary skill in the pertinent arts. A suitable example is described in “A Sweepline Algorithm for Voronoi Diagrams,” Algorithmica , Vol. 2, pp. 153-174 (1987), the disclosure of which is incorporated herein by reference. The triangulation module 112 accepts declared terrain points as input from the terrain test module 111 , and it operates on the horizontal coordinates of the points by connecting adjacent points to form triangles. The output of the processing is a list of triples from the vertex list identifying the three corners of each triangle. The processing rate of this calculation is r 4 .
[0052] The predicted range module 113 calculates the predicted range by combining the current position, supplied by a navigation system (such as GPS/INS), with the last terrain model provided by a coordinate transformation module 114 . The processing rate of this calculation is r 3 . The coordinate transformation module 114 provides coordinate transformations on the terrain geometry model in earth-fixed coordinates received from the terrain test module 111 (vertex list) and the triangulation module 112 (vertex triples or triangle list). The predicted range module 113 accepts the earlier terrain model information in current coordinates and calculates a predicted range used to refine the current range estimate. The processing rate of this calculation is r 4 .
[0053] A summing module 115 adds a perspective offset to position data supplied by the GPS/INS navigation system to represent actual position.
[0054] The terrain image intensity function 103 includes an image transformation module 116 , an amplitude-summing module 117 , and an intensity-mapping module 118 . The image transformation module 116 transforms the location of each radar return from the moving radar coordinate system to the earth-fixed frame, and projects (via the summing module 117 ) all data into a horizontal area in the earth-fixed coordinate system (the image frame). The processing rate of this calculation is r 3.
[0055] The intensity mapping module 118 forms the texture map used by the graphics. The illuminated area 17 of the image plane 16 ( FIGS. 1A and 1B ), illuminated by the current radar scan, is divided into 2″ by 2″ bins. The radar return signal amplitudes of all returns above each bin are summed and projected into a single bin. The processing rates for the amplitude-summing module 117 and the intensity mapping module 118 are r 3 and r 4 , respectively.
[0056] The graphics module 104 performs the actual image rendering as described briefly above. The inputs defining the terrain include the 3D mesh of triangles (vertex and triangle lists) with associated values for color or grey scale for each vertex, and a texture map defining intensity. Obstacle inputs can be in the form of points or another independent pair of vertex/triangle lists, causing 3D surfaces to be drawn above the terrain surface (akin to hanging sheets of paper oriented perpendicular to the look direction). An image perspective is defined by a location and the look direction. During a rendering process, grey-scale shading or coloring of the triangular surfaces is added by blending the values assigned to the vertices across each triangular area with the intensity being derived from the radar return signal amplitude. The result is a 3D surface consisting of triangles approximating the detected surface, where the grey-scale or color within each triangle varies to match values calculated for the three vertices based on vertex height or another geometrical relationship (e.g., range from the image perspective), and the intensity varies with the amplitude of the radar return signal. In some applications, weighting the triangle (grey-scale or color) based on distance from a desired perspective point can be used to enhance depth perception and ridgeline detection. The graphics module 104 is used to transform the 3D image to the desired perspective (e.g., from the pilot's seat, looking in the direction of the fuselage reference line). FIGS. 8A-8D illustrate the results of the rendering process, as displayed on a video display screen 200 in the aircraft 10 .
[0057] The foregoing 3D radar image rendering system provides imagery based on real time measured elevation angles from the pilot's perspective, thereby assuring that the elevation angle appears correct in the recently created image. The vertical resolution of the radar imagery is determined by radar range resolution, as opposed to radar elevation angle resolution, with the resulting vertical positioning being based on real time direct angle measurement.
[0058] The use of geometry, elevation, and range from the image perspective point in addition to radar return helps to minimize the variation in the reflected power levels from uniform surfaces. This geometry data is used to make up for the missing radiated power from radar data and thus facilitates better human visualizations, which relies on both radiated power and reflected power. Furthermore, the present invention improves image resolution, realized by drawing sides of the triangles between points on the reflecting surface, as opposed to the use of fixed-size angular pixels related to radar antenna beam width.
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A 3D rendered image of a radar-scanned terrain surface is provided from a radar return signal from the surface, wherein the return signal includes data indicative of azimuth, elevation, and range of a radar-illuminated area of the surface. The data are processed for transformation into X, Y, and Z coordinates. The X and Y coordinates corresponding to each illuminated area are triangulated so as to create a mesh of triangles representing the terrain surface, each of the triangles in the mesh being defined by a vertex triplet. 3D imaging information (grey scale shading and/or coloring information) is added to each triangle in the mesh, based on the amplitude of the radar return signal from the coordinates represented by each vertex in the triplet and the value of the Z coordinate at each vertex, so as to form the 3D rendered image.
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RELATED APPLICATIONS
[0001] This application claims the benefit of priority of Korean Patent Application No. 2003-0034915, filed on May 30, 2003, the entire disclosure of which is expressly incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a recombinant vector for transforming a strain to detect benzoic acid and derivatives thereof, transformant containing the recombinant vector, and a method for detecting benzoic acid and derivatives thereof using the transformant. More particularly, the present invention relates to a recombinant vector for transforming a strain to detect benzoic acid and derivatives thereof which can determine to what degree soil contaminated with polyaromatic hydrocarbons has been recovered, a transformant containing the recombinant vector, and a method for detecting benzoic acid and derivatives thereof by measuring bioluminescence generated after reacting the transformant with a sample to be tested.
[0004] 2. Description of the Related Art
[0005] Since aromatic compounds are stable in view of their structure, they are limitedly biodegradable in nature. For this reason, the aromatic compounds in soil cause serious soil contamination. Polyaromatic hydrocarbons, non-biodegradable compounds, are partially biodegraded by microorganisms present in soil and can be used as carbon sources. Thus, studies on biological methods for recovering contaminated soil using soil microorganisms are being actively undertaken.
[0006] Since benzoic acid and derivatives thereof are aromatic compounds obtained as intermediate metabolites during natural degradation of polyaromatic compounds, the analysis of benzoic acid and derivatives thereof in the course of recovery of soil contaminated with polyaromatic hydrocarbons facilitates the determination of the degree of soil recovery.
[0007] Conventional instrumental analyses are advantageous in that they can provide quantitative analysis of chemical data, but have disadvantages that the toxicity of chemicals to be analyzed cannot be environmental toxicologically measured and analysis on intracellular reaction cannot be performed.
[0008] Trials to monitor and classify the toxicity of chemicals using bioluminescent bacteria are currently ongoing. For example, a method for determining the degree of a certain stress caused by a specific chemical as bioluminescence intensity was reported (M. B. Gu and S. H. Choi, Water Science and Technology, 43: 147-154). According to this method, a bioluminescent gene is linked to a stress promoter which can induce the expression of a bioluminescent substance upon causing stress. In addition, a protein-coding gene involved in the intermediate metabolism associated with the degradation of a specific chemical, and a promoter inducing expression of the gene are used for the detection of the chemical (Burlage, R. S., Sayler, G. S., Larimer, F, J. Bacteriol. 172:4749-4757). Accordingly, the production of bioluminescent bacteria using gene recombination techniques can be broadly applied to the biological testing methods of chemicals.
[0009] However, despite many advantages of biological testing methods described above, no technology has been established that provides methods for analyzing benzoic acid and derivatives thereof generated during recovery of soil contaminated with polyaromatic hydrocarbons.
SUMMARY OF THE INVENTION
[0010] Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a recombinant vector for transforming a strain to detect benzoic acid and derivatives thereof which can determine to what degree soil contaminated with polyaromatic hydrocarbons has been recovered.
[0011] It is another object of the present invention to provide a transformant produced by transforming Escherichia coli with the recombinant vector.
[0012] It is yet another object of the present invention to provide a method for detecting benzoic acid and derivatives thereof by measuring bioluminescence generated after reacting the transformant with a sample to be tested.
[0013] In accordance with one aspect of the present invention, there is provided a recombinant vector for transforming a strain to detect benzoic acid and derivatives, comprising:
[0014] a bioluminescent gene encoding a bioluminescent protein; and
[0015] a gene set inducing the expression of the bioluminescent gene,
[0016] wherein the gene set includes the regulatory gene nagR and a promoter region inducing the transcription of the bioluminescent gene via the action of protein NagR encoded by the gene nagR.
[0017] In accordance with another aspect of the present invention, there is provided a transformant produced by transforming E. coli with the recombinant vector.
[0018] In accordance with yet another aspect of the present invention, there is provided a method for detecting benzoic acid and derivatives thereof by measuring bioluminescence generated after reacting the transformant with a sample to be tested.
[0019] The regulatory protein NagR expressed by the nagR gene binds to a promoter which operates nag operon, i.e., genes comprising nagAaGHAbAcAdBFCQED, involved in the conversion of naphthalene to gentisate to regulate the transcription of the nag operon (S. L. Fuenmayor, M. Wild, A. L. Boyes, and P. A. Williams, J. Bacteriol. 180: 2522-2530).
[0020] The promoter region of the nag operon is designated as ‘PnagG’, whose operation is regulated by the regulatory protein NagR expressed by the nagR gene. The main mechanism is explained based on the observation that when the regulatory protein bound with benzoic acid and derivatives thereof binds to the promoter region, it affects the expression of the bioluminescent gene.
[0021] The gene set which induces the expression of the bioluminescent gene includes the nagR gene and the PnagG, a promoter region of the nag operon. The gene set (nagR-P nagG ) functions like a single promoter, and can be obtained by PCR amplification of 5′ primer (5′-GTCACCAATATGGACCAGGCAACGC-3′) shown in SEQ ID NO: 1 and 3′ primer (5′-CCGCGTCTAGATGCTAATTGAGGGG-3′) shown in SEQ ID NO: 2 derived from Ralstonia sp. U2. The PCR product thus obtained is treated with a particular restriction enzyme and is then inserted into a specific vector previously treated with the same restriction enzyme to produce a recombinant vector. Thereafter, the recombinant vector is recombined with a specific vector carrying a bioluminescent gene to produce a recombinant vector for transforming the E. coli to detect benzoic acid and derivatives thereof according to the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The above and other objects, 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.
[0023] [0023]FIG. 1 is a diagram showing a method for producing a recombinant vector (PNAG1) according to the present invention.
[0024] [0024]FIG. 2 is a photograph showing the result determined by agarose gel electrophoresis after cleaving a recombinant vector (pNAG1) of the present invention pNAG1 with restriction enzymes EcoR1 and Kpn1 (left lane: marker, right lane: vector fragment).
[0025] [0025]FIGS. 3 a and 3 b are graphs showing changes in the bioluminescence after treating a transformant (EBNAG1) of the present invention with benzoic acid (a) and salicylic acid (b), as a benzoic acid derivative, at various concentrations, respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0026] Hereinafter, the present invention will be explained in more detail with reference to the accompanying drawings. FIG. 1 is a cleavage map showing a method for producing a recombinant vector for transforming E. coli to detect benzoic acid and derivatives thereof, in accordance with a preferred embodiment of the present invention. Referring to FIG. 1, recombinant plasmid pNAG1 is produced by fusing a promoter containing the nagR gene and P nagG to lux CDABE, a bioluminescent gene. The nagR gene derived from Ralstonia sp. U2 promotes the catabolism of naphthalehe, and the P nagG is a promoter of the nag operon.
[0027] Primers shown in SEQ ID NOs: 1 and 2 from the genome of Ralstonia sp. U2 are amplified to obtain a 1.331-kb PCR product shown in SEQ ID NO: 3. The PCR product includes a −266 bp downstream section and a +176 bp upstream section of the nagR gene, and contains promoter regions of nagR [267˜1172 bp] and nagAa gene [1173˜1288 bp]. The PCR product is treated with restriction enzymes Xba1 and HindIII, and then recombined to pSP-luc+ previously treated with the same enzymes to produce a recombinant plasmid designated as ‘pNAG9’.
[0028] The pNAG9 plasmid is treated with restriction enzymes Kpn1 and EcoR1, and is then recombined to the multicloning site of pUCD615 which contains luxCDABE treated with the same restriction enzymes, to produce a recombinant plasmid designated as ‘pNAG1’. Preferably, the recombinant plasmid pNAG1 contains an antibiotic resistance gene. Examples of the antibiotic resistance gene used in the present invention include many known genes, e.g., kanamycin-, ampicillin-, tetracycline-resistance genes, etc. Accordingly, a person skilled in the art can appropriately select the desired gene from these antibiotic resistance genes, but the constitution of the present invention is not limited to the specific kind of the genes. Since the antibiotic resistance gene is introduced for the selection of a desired transformant, any genes that are used for the selection can be introduced. Accordingly, genes introduced into the recombinant plasmid pNAG1 are not limited to these antibiotic resistance genes.
[0029] In the following examples of the present invention, the E. coli RFM443 strain is used as a microorganism transformed by the recombinant plasmid pNAG1. E. coli is most suitably used in terms of simple culturing conditions and easy manipulation, but the present invention is not limited thereto. The pNAG1 plasmid carrying the kanarycin- or ampicillin-resistance gene is introduced into the E. coli RFM443, and then grown on an LB medium supplemented with ampicillin, from which colonies containing the plasmid pNAG1 can be screened.
[0030] The present inventors screened a strain showing bioluminescence response to benzoic acid and salicylic acid as a representative benzoic acid derivative, and designated it as ‘ E. coli RFM443/pNAG1 (EBNAG1)’. The E. coli RFM443/pNAG1 (EBNAG1) was deposited on Apr. 4, 2003 with the Korean Agricultural Culture Collection (KACC) under the accession No. KACC 91044.
[0031] When the transformant EBNAG1 (KACC 91044) of the present invention detects the presence of benzoic acid and derivatives thereof, the bioluminescence intensity increases. Accordingly, the measurement of bioluminescence generated after exposing the strain of the present invention to a sample to be tested enables not only the detection of benzoic acid and derivatives thereof as representative soil contaminants, but also the detection of the toxicity and harmfulness of benzoic acid and derivatives thereof present in water.
[0032] Hereinafter, the present invention will be described in more detail with reference to the following examples. However, these examples are given for the purpose of illustration and are not to be construed as limiting the scope of the invention.
EXAMPLE 1
Production of Recombinant Plasmid
[0033] A 1.33 kb PCR product, i.e. nagR-P nagG promoter, was obtained by PCR amplification of primers shown in SEQ ID NOs: 1 and 2 derived from Ralstonia sp. U2. Since the PCR product requires restriction enzyme sites of Kpn1 and EcoR1 to combine to pUCD615 as a terminal vector, pSP-luc+ (Promega, USA) having restriction enzyme sites of Kpn1 and EcoR1 was used. At this time, the PCR product and the vector pSP-luc+ were treated with restriction enzymes Xab1 and HindIII at 37°X for 2 hours, respectively, to remove the luc gene from the vector, and were then recombined to each other to produce a recombinant plasmid (pNAG9).
[0034] The plasmid pNAG9 was treated with restriction enzymes Kpn1 and EcoR1 at 37° C. for 2 hours, and recombined to multicloning sites of pUCD615 containing luxCDABE previously treated with the same restriction enzymes to produce a recombinant plasmid designated as ‘pNAG1’ (FIG. 1).
EXAMPLE2
Production of Transformant EBNAG1
[0035] First, wild-type strain RFM443 was cultivated at 37° C. for 1 day. Salt ingredients present in the bacterial culture were removed using 50% glycerol, and the strain was then electroporated to produce viable host cells. The plasmids produced in Example 1 were inserted into the host cells, and subjected to electroporation in an electroporation system (Bio-RAD, Gene Pulser R II) for 2 seconds. The electroporated host cells were spread onto an LB-agar plate supplemented with 50 μg/ml ampicillin. The plate was placed in an incubator at 30° C. and incubated for 1 day to form colonies. The colonies were seeded onto a 100 ml LB medium supplemented with 50 μg/ml ampicillin, transferred into a rotary incubator at 30° C., and incubated for 1 day. Thereafter, recombinant plasmid (PNAG1) was isolated from the culture using a commercially available Miniprep kit (Qiagen). The plasmids were treated with restriction enzymes Kpn1 and EcoR1, which was previously used to produce the recombinant plasmid in Example 1, to identify the production of the plasmid, and 11-kb pUCD615 vector and a 1.06 kb promoter region were then identified using a 0.8% agarose gel (FIG. 2).
EXAMPLE3
Determination of Detectability of Transformant EBNAG1 on Benzoic Acid and Derivatives Thereof
[0036] The EBNAG1 strain was cultivated in a 100 ml LB medium supplemented with 50 μg/ml ampicillin at 30° C. until the absorbance reached 0.08 (at 600 nm). 100 μl of aliquot was taken from the culture for the measurement of the bioluminescence intensity, and was then poured on each well of an opaque96-well plate [Microlite™, Thermo Labsystems, USA] containing chemicals to be tested (benzoic acid concentrations: 12.5, 6.25, 3.125, 1.5625, 0.78125, 0.390625 and 0.1953125 mM, and salicylic acid concentrations: 12.5, 6.25, 3.125, 1.5625, 0.78125, 0.390625 and 0.1953125 mM). The well plates were placed in a 96-well microtiter plate reader (MLX Microtiter® Plate Luminometer, DYNEX Technology, USA) to measure the bioluminescence intensity.
[0037] Then, changes in the bioluminescence intensity were observed for 6 hours at varying chemical concentrations. FIGS. 3 a and 3 b show the results of bioluminescent signals obtained from EBNAG1 after seeding benzoic acid and salicylic acid as a representative benzoic acid derivative at various concentrations, respectively. As can be seen from the graph of FIG. 3 a, the bioluminescence intensity varied with increasing benzoic acid concentrations 3 hours after seeding. It was also observed that the bioluminescence intensity increased in proportion to the benzoic acid concentrations. In addition, as can be seen from the graph of FIG. 3 b, the bioluminescence intensity varied with increasing salicylic acid concentrations 3 hours after seeding. It was also observed that the bioluminescence intensity increased in proportion to the salicylic acid concentrations. These results suggest that the recombinant plasmid pNAG1 can be used to detect the toxicity of a chemical present in a sample, as well as the toxicity depending on the concentrations of benzoic acid and derivatives thereof. The degrees of EBNAG1 response to benzoic acid and other benzoic acid derivatives are shown in Table 1 below.
TABLE 1 Maximum RBL a Compounds (Concentration) MDC b (mM) Benzoic acid 344 (12.5 mM) 0.39 Salicylic acid 51.2 (6.25 mM) 0.195 4-Chlorosalicylic acid 92.7 (1.56 mM) <0.39 5-Chlorosalicylic acid 8.8 (1.56 mM) 0.39 2,4-Dihydroxybenzoic acid 11.4 (6.25 mM) 3.13 3,4-Dihydroxybenzoic acid 10.9 (6.25 mM) 6.25 3,5-Dihydroxybenzoic acid 13.0 (12.5 mM) 3.13 3,4-Dimethoxybenzylalcohol 4.92 (6.25 mM) 0.39
[0038] According to the present invention, the toxicity and harmfulness of benzoic acid as an aromatic compound and derivatives thereof present in soil can be analyzed without the use of complex instruments. Since benzoic acid and derivatives thereof are aromatic compounds obtained as intermediate metabolites during natural degradation of polyaromatic compounds, the analysis of benzoic acid and derivatives thereof in the course of recovery of soil contaminated with polyaromatic hydrocarbons facilitates the determination of the degree of soil recovery.
[0039] Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.
1
3
1
25
DNA
Artificial Sequence
synthetic primer
1
gtcaccaata tggaccaggc aacgc 25
2
25
DNA
Artificial Sequence
synthetic primer
2
ccgcgtctag atgctaattg agggg 25
3
1331
DNA
Ralstonia sp.U2
gene
(267)...(1172)
nagR gene
3
gtcaccaata tggaccaggc aacgcaacag aacgcggcgc tggtcgagca gatggccgcc 60
gcggcctcca gactgaaggg tcagtccgaa gagctggtgc agacggtggc ggtgttcaaa 120
ctggcggacg atggcagttc cgacccggct gcctacgcac aagaccagtc gcatgggaga 180
actgcgccgc accggttggc agaccaccga catcctgatc ctcagccatg gccgaccgcg 240
gcagtcaata tgggtttgct ggaagcttat gcttcagaga aaagctcgac gaacaactga 300
cgtagccaca tgttgcccgg atcccggttg tacttggcat gccaaaacag gttgatggcg 360
atgtcgggca gcttggccgg gtgcggggat gtcgtcagac caaaaggcac ttcgcagcga 420
acggcaaaac gctgcggcac ggtcgcgatg aggtcggtgc tgtgcagaat ggggccgatc 480
gcaatgaaat gcggcaccac cagccgcatg cgccttttga tgcctgcgcg ttcgagcagg 540
ccatcgacct caccgtgtcc ggtgttgagt gcgaccacgc cgacatgctc cagttcactg 600
aactgtttca ggctcatggg ggatttggcg cttggatggt ccttgcggaa catgcatacg 660
tagcggtggc gaaagaggcg ccgctggaag aatccggtct gtagctctgg cagaagaccc 720
aaggcgagat caaccgcacc ggactccata tcctccttca gattgccagc attcgggcgc 780
agcgtgctga tctggatgtg aggagctcgt tgcgcaagcg cttccatcag tgggggcatg 840
aagtacatct cgccgatgtc ggtcattgcc aagttgaagg tgcgcgtgct ggcaaatggg 900
tcgaaagagt cacgggtcgt cagtgccgtc tgcagcgtgt tgagcgcata gatcacgggc 960
tccgcaagat gcagtgcata cggtgtcggc tccatgcctt ttgaggtgcg caagaacaaa 1020
tcgtccttta gcgccgcacg cagccgttta agtgaattgc tgacggcagg ctgcgtcagc 1080
cccagttttt cgccggccgt cgatacgctc cggtcgagca gtagctggtt gaagaccacc 1140
agcagattca agtcgatgtc gcgcagatcc atgatgcctc accattattc atgctggtga 1200
ttttaactat cagacttgat ctatagcgct ataccgatcg acgcgccaga atcgcagcca 1260
ttcggagaca actgaaaaaa gagcttgcat ggaactggta gtagaacccc tcaattagca 1320
tctagacgcg g 1331
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Disclosed herein is a recombinant vector for transforming a strain to detect benzoic acid and derivatives, comprising a bioluminescent gene encoding a bioluminescent protein and a gene set inducing the expression of the, bioluminescent gene wherein the gene set includes the regulatory gene nagR and a promoter region inducing the transcription of the bioluminescent gene via the action of protein NagR encoded by the gene nagR. Further disclosed are a transformant containing the recombinant vector and a method for detecting benzoic acid and derivatives, thereof by measuring bioluminescence generated after reacting the transformant with a sample to be tested.
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CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims benefit of priority to U.S. Provisional Patent Applications Serial No. 60/406,127, filed Aug. 27, 2002 and 60/422,436, filed Oct. 30, 2002, both of which are incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] Metered dose inhalers have proven to be effective oral and nasal delivery systems that have been used extensively for delivering bronchodilating and steroidal compounds to asthmatics, as well as delivering other compounds such as pentamidine and non-bronchodilator anti-inflammatory drugs. The rapid onset of activity of compounds administered in this manner and the absence of any significant side effects have resulted in a large number of compounds being formulated for administration via this route. Typically, the drug is delivered to the patient by a propellant system generally comprising one or more propellants which have the appropriate vapor pressure and which are suitable for oral or nasal administration. The propellant systems typically comprised CFC propellant 11, CFC propellant 12, CFC propellant 114 or mixtures thereof. Often the vapor pressure of the propellant systems is adjusted by admixing a less volatile liquid excipient with the propellant.
[0003] However, propellants CFC 11, CFC 12 and CFC 114 belong to a class of compounds known as chlorofluorocarbons, which have been linked to the depletion of ozone in the atmosphere. It has been postulated that ozone blocks certain harmful UV rays and thus a decrease in the atmospheric ozone content will result in an increase in the incidence of skin cancer. In the 1970's certain steps were taken to reduce the CFC emissions from aerosols. Other propellants, such as hydrocarbons, were used, or the product was delivered in a different manner. Because CFC usage in medicinal applications is relatively low i.e. less than 1% of total CFC emissions, and because of the health benefits associated with metered dose inhalers, steps were not taken at that time to restrict the use of CFC propellants in metered dose inhalers.
[0004] However, continuing and more sophisticated ozone measurements have indicated that the earlier restrictions in CFC usage were insufficient and that additional, significant steps should be taken to drastically reduce CFC emissions. Recommendations have been made that CFC production be virtually discontinued. As a result, it may not be possible to continue to use CFC propellants in the intermediate and long term. While some efforts have been made to use non-pressurized metered dose inhalers, many of these devices have not been completely successful. Some of the performance issues related to these are: delivery of uniform doses, mechanical complexity, ability to provide the required doses per unit of an aerosol container, ability to meet stringent regulatory standards, the inhalers can be difficult for individuals to utilize, and are bulky and/or cumbersome for the patients to use, particularly when patients have an acute need for the medication.
[0005] As a result, there is a need for pressurized aerosol formulations, such as metered dose inhalers, which are substantially free of CFC's. Non-CFC propellants systems must meet several criteria for pressurized metered dose inhalers. They must be non-toxic, stable and non-reactive with the medicament and the other major components in the valve/actuator. One propellant which has been found to be suitable is CF 3 CHFCF 3 , also known as HFA 227, HFC 227 or 1,1,1,2,3,3,3 heptafluoropropane. Another such propellant for use in metered dose inhalers is CF 3 CH 2 F, also known as 1,1,1,2-tetrafluoroethane or HFA 134a.
[0006] Filling processes of the canister used in metered dose inhalers that contain the medication typically employ a two stage process for filling canister. In one such process, the drug, surfactant, i.e., oleic acid and the non-volatile excipient, i.e., ethanol, are filled into the container in the first stage, and the propellant is added in to the container in the second stage. For CFC propellant formulations, typically a surfactant is mixed with a less volatile propellant (i.e. P-11) and then there is added a more volatile propellant through the valve.
[0007] Mometasone MDI-AP has previously been manufactured using such a conventional pressure filling process. This process is a two-stage process. In the first stage the drug is mixed in with oleic acid and alcohol to form a homogenous well-dispersed suspension which is typically called the “concentrate.” The required amount of concentrate is filled into an open can. In the second stage the valve is then crimped onto the can and the propellant (HFA 227) is filled into the can through the valve. A significant disadvantage of this formulation is that this two-stage manufacturing process resulted in particle size growth of the drug while the concentrate was being filled during a typical manufacturing and filling operation. A fine particle size is essential for delivery of aerosolized suspensions to the deeper passages of the lungs. In addition, this is a less accurate fill method. Drug concentrate typically comprises less than 5% of the formulation and problems can arise with regards to the accurate filling at these low concentrations.
[0008] However, the specific combinations noted above may not provide the desired solubility, stability, low toxicity, exact dosage, correct particle size (if suspension) and/or compatibility with commonly used valve assemblies of metered dose inhalers. Accordingly, there exists a need for CFC free formulations for the treatment of asthma, and processes for producing the same, that do not suffer from the aforementioned infirmities.
SUMMARY OF THE INVENTION
[0009] Accordingly, the present invention is directed to process for introducing a suspension or solution of mometasone furoate anhydrous into a metered dose inhaler container, said container having a valve attached thereto, said method comprising the steps of: a) introducing mometasone furoate anhydrous, a surfactant and a chlorflourocarbon free propellant into a vessel that is held under pressure to form a suspension or solution; b) circulating said suspension or solution from the vessel through a line which includes a filling head; c) bringing said filling head into communication with said metered dose inhaler container through said valve of said metered dose inhaler container; d) introducing a quantity of such suspension or solution into the container from the filling head of the line through said valve of said metered dose inhaler container; e) withdrawing said filling head from said metered dose inhaler container; and f) sealing said metered dose inhaler container. The present invention also is directed to the product produced by the aforementioned method.
[0010] The present invention is also directed to a process for introducing a suspension or solution of mometasone furoate anhydrous and formoterol fumarate into a metered dose inhaler container, said container having a valve attached thereto, said method comprising the steps of: a) introducing mometasone furoate anhydrous, formoterol fumarate, a surfactant and a chlorflourocarbon free propellant into a vessel that is held under pressure to form a suspension or solution; b) circulating said suspension or solution from the vessel through a line which includes a filling head; c) bringing said filling head into communication with said metered dose inhaler container through said valve of said metered dose inhaler container; d) introducing a quantity of such suspension or solution into the container from the filling head of the line through said valve of said metered dose inhaler container; e) withdrawing said filling head from said metered dose inhaler container; and f) sealing said metered dose inhaler container.
[0011] There is also disclosed a process for introducing a suspension or solution of mometasone furoate anhydrous into a metered dose inhaler container, said container having a valve attached thereto, said method comprising the steps of: a) introducing mometasone furoate anhydrous, a surfactant and a chlorflourocarbon free propellant into a vessel that is held under pressure to form a suspension or solution, wherein said pressure is greater than about 30 psi; b) circulating said suspension or solution from the vessel through a line which includes a filling head and a double diaphragm pump; c) bringing said filling head into communication with said metered dose inhaler container through said valve of said metered dose inhaler container; d) introducing a quantity of such suspension or solution into the container from the filling head of the line through said valve of said metered dose inhaler container; e) withdrawing said filling head from said metered dose inhaler container; and f) sealing said metered dose inhaler container.
[0012] Also disclosed is a process for introducing a process for introducing a suspension or solution of a compound selected from the group consisting of mometasone furoate anhydrous, formoterol fumarate and combinations thereof, into a metered dose inhaler container, said container having a valve attached thereto, said method comprising the steps of: a) introducing mometasone furoate anhydrous, formoterol fumarate and combinations thereof, a surfactant and a chlorflourocarbon free propellant into a vessel that is held under pressure to form a suspension or solution, wherein said pressure is about 10 psi to about 15 psi; b) circulating said suspension or solution from the vessel through a line which includes a filling head and a double diaphragm pump; c) bringing said filling head into communication with said metered dose inhaler container through said valve of said metered dose inhaler container; d) introducing a quantity of such suspension or solution into the container from the filling head of the line through said valve of said metered dose inhaler container; e) withdrawing said filling head from said metered dose inhaler container; and f) sealing said metered dose inhaler container.
[0013] Also disclosed is process for introducing a suspension or solution of mometasone furoate anhydrous into a metered dose inhaler container, said container having a valve attached thereto, said method comprising the steps of: a) introducing mometasone furoate anhydrous, a surfactant and a chlorflourocarbon free propellant into a vessel that is held under pressure to form a suspension or solution, wherein said pressure is greater about 0 psi to about 10 psi; b) circulating said suspension or solution from the vessel through a line which includes a filling head and a single diaphragm pump; c) bringing said filling head into communication with said metered dose inhaler container through said valve of said metered dose inhaler container; d) introducing a quantity of such suspension or solution into the container from the filling head of the line through said valve of said metered dose inhaler container; e) withdrawing said filling head from said metered dose inhaler container; and f) sealing said metered dose inhaler container as well as the products produced thereby.
DETAILED DESCRIPTION OF THE INVENTION
[0014] According to the present invention the metered dose inhaler formulation is manufactured utilizing a new process in which the particle size growth of the drug on manufacturing/filling is eliminated.
[0015] In one embodiment of the invention, this new process, the entire formulation drug/oleic acid/alcohol/HFA 227 is mixed in a single compounding vessel which is covered by a lid under pressure. This pressurized vessel allows for the gaseous propellant to exist in the liquid state. Next, the formulation in liquid form (some of the HFA 227 may be in the gaseous state) is filled in one-stage through the valve of an empty metered dose inhaler canister containing a previously crimped on valve.
[0016] In another embodiment of the invention, this new process also resulted in markedly reducing particle size growth of drug in metered dose inhaler formulation, as compared to the particle size growth seen with the conventional two-stage manufacturing process.
[0017] This new process provides improved product quality due to better fill tolerance associated with the new process. Additionally, the new process also results in operational improvements such as a) one filling station, b) no need for concentrate and neat propellant sample checks.
[0018] Most preferably, in accordance with the present invention, the dosing systems containing at least one pharmacologically active agent or drug is a material capable of being administered to the respiratory system, including the lungs. For example, a drug in accordance with the present invention could be administered so that it is absorbed into the blood stream through the lungs.
[0019] A particularly preferred corticosteroid is mometasone furoate, the active component of ELOCON® lotion, cream, and ointment, and NASONEX® nasal spray, that is an anti-inflammatory corticosteroid having the chemical name, 9,21-Dichloro-11(beta), 17-dihydroxy-16(alpha)-methylpregna-1,4-diene-3,20-dione 17-(2 furoate). Mometasone furoate is a preferred active ingredient, although other active ingredients and/or combinations thereof may be used within the scope of the present invention. Mometasone furoate is a white powder, with an empirical formula of C 27 H 30 C 12 O 6 . It is practically insoluble in water; slightly soluble in methanol, ethanol, and isopropanol; soluble in acetone and chloroform; and freely soluble in tetrahydrofuran. Mometasone can exist in various hydrated, crystalline and enantiomeric forms, e.g., as a monohydrate. This product is available from Schering-Plough Corporation, Kenilworth, N.J.
[0020] Also prefererred pharmacologically active agents in accordance with the present invention include, for example, Formoterol (also known as eFormoterol) e.g., as the fumarate or tartrate, a highly selective long-lasting β 2 -adrenergic agonist having bronchospasmolytic effect, is effective in the treatment of reversible obstructive lung ailments of various genesis, particularly asthmatic conditions.
[0021] Another particularly preferred β-agonist is albuterol sulfate. The active component of PROVENTIL® HFA (albuterol sulfate) Inhalation Aerosol is albuterol sulfate, USP racemic (alpha) 1 [(tert-Butylamino)methyl]-4-hydroxy-m-xylene-(alpha),(alpha)′-diol sulfate (2:1)(salt), a relatively selective beta 2 -adrenergic bronchodilator. Albuterol sulfate is the official generic name in the United States. The World Health Organization recommended name for the drug is salbutamol sulfate. Albuterol sulfate is a white to off-white crystalline solid. It is soluble in water and slightly soluble in ethanol. PROVENTIL® HFA Inhalation Aerosol is a pressurized metered-dose aerosol unit for oral inhalation. It contains a microcrystalline suspension of albuterol sulfate in propellant HFA-134a (1,1,1,2-tetrafluoroethane), ethanol, and oleic acid. PROVENTIL® HFA is available from Schering-Plough Corp., Kenilworth, N.J.
[0022] Several of these compounds could be administered in the form of pharmacologically acceptable esters, salts, solvates, such as hydrates, or solvates of such esters or salts, if any. The term is also meant to cover both racemic mixtures as well as one or more optical isomers.
[0023] It is preferred that the formulation be a CFC-free pressurized aerosol formulation. Non-CFC propellants systems must meet several criteria for pressurized metered dose inhalers. They must be non-toxic, stable and non-reactive with the medicament and the other major components in the valve/actuator. One propellant which has been found to be suitable for use in the present invention is CF 3 CHFCF 3 , also known as HFA 227, HFC 227 or 1,1,1,2,3,3,3 heptafluoropropane, hereinafter HFA 227. Another such propellant for use in the present invention is CF 3 CH 2 F, also known as 1,1,1,2-tetrafluoroethane or HFA 134a, hereinafter HFA 134a.
[0024] In formulations of the present invention which are suitable for treating lower respiratory system disorders such as asthma, at least a substantial portion of the drug is present as suspended particles having respirable sizes, e.g., about 0.5 to about 10 micrometers in their largest dimension. In formulations which are suitable for treating upper respiratory system disorders such as rhinitis, somewhat larger drug particles may be permissible, but the foregoing size range remains preferred.
[0025] The processes for producing the formulations of the present invention utilize propellants HFA 227 or HFA 134a, or a combination thereof, in combination with a pharmacologically active agent, preferably but not limited to mometasone furoate anhydrous, optionally, a liquid excipient, and optionally a surfactant. The excipient facilitates the compatibility of the medicament with the propellant and also lowers the discharge pressure to an acceptable range, i.e., about 2.76-5.52×10 5 newton/meter 2 absolute (40 to 80 psi), preferably 3.45-4.83×10 5 newton/meter 2 absolute (50 to 70 psi). The excipient chosen must be non-reactive with the medicaments, relatively non-toxic, and should have a vapor pressure below about 3.45×10 5 newton/meter 2 absolute (50 psi).
[0026] As used hereinafter the term “medium chain fatty acids” refers to chains of alkyl groups terminating in a —COOH group and having 6-12 carbon atoms, preferably 8-10 carbon atoms. The term “short chain fatty acids” refers to chains of alkyl groups terminating in a —COOH group and having 4-8 carbon atoms. The term “alcohol” includes C 1 -C 3 alcohols, such as methanol, ethanol and isopropanol.
[0027] Among the preferred excipients are: propylene glycol diesters of medium chain fatty acids available under the tradename Miglyol 840 (from Huls America, Inc. Piscataway, N.J.); triglyceride esters of medium chain fatty adds available under the tradename Miglyol 812 (from Huls); perfluorodimethylcyclobutane available under the tradename Vertrel 245 (from E. I. DuPont de Nemours and Co. Inc. Wilmington, Del.); perfluorocyclobutane available under the tradename octafluorocyclobutane (from PCR Gainsville, Fla.); polyethylene glycol available under the tradename EG 400 (from BASF Parsippany, N.J.); menthol (from Pluess-Stauffer International Stanford, Conn.); propylene glycol monolaurate available under the tradename lauroglycol (from Gattefosse Elmsford, N.Y.); diethylene glycol monoethylether available under the tradename Transcutol (from Gattefosse); polyglycolized glyceride of medium chain fatty adds available under the tradename Labrafac Hydro WL 1219 (from Gattefosse); alcohols, such as ethanol, methanol and isopropanol; eucalyptus oil available (from Pluses-Stauffer International); and mixtures thereof.
[0028] A surfactant optionally may be added to lower the surface and interfacial tension between the medicaments and the propellant. Where the medicaments, propellant and excipient are to form a suspension, a surfactant may or may not be required. Where the medicament, propellant and excipient are to form a solution, a surfactant may or may not be necessary, depending in part, on the solubility of the particular medicament and excipient. The surfactant may be any suitable, non-toxic compound which is non-reactive with the medicament and which substantially reduces the surface tension between the medicament, the excipient and the propellant and/or acts as a valve lubricant.
[0029] A surfactant may also frequently included in aerosol formulations, for purposes such as assisting with maintaining a stable suspension of the drug and lubricating the metering valve. The formulation of the present invention does not require a surfactant for maintenance of ready dispersability (such as by moderate agitation immediately prior to use), as the drug forms loose floccules in the formulation and does not exhibit a tendency to settle or cream when alcohol is present. Upon undisturbed storage, the drug particles remain suspended in their flocculated state when alcohol is present.
[0030] Among the preferred surfactants are: oleic acid available under the tradename oleic acid NF6321 (from Henkel Corp. Emery Group, Cincinnati, Ohio); cetylpyridinium chloride (from Arrow Chemical, Inc. Westwood, N.J.); soya lecithin available under the tradename Epikuron 200 (from Lucas Meyer Decatur, Ill.); polyoxyethylene(20) sorbitan monolaurate available under the tradename Tween 20 (from ICI Specialty Chemicals, Wilmington, Del.); polyoxyethylene(20) sorbitan monostearate available under the tradename Tween 60 (from ICI); polyoxyethylene(20) sorbitan monooleate available under the tradename Tween 80 (from ICI); polyoxyethylene (10) stearyl ether available under the tradename Brij 76 (from ICI); polyoxyethylene (2) oleyl ether available under the tradename Brij 92 (frown ICI); Polyoxyethylene-polyoxypropylene-ethylenediamine block copolymer available under the tradename Tetronic 150 R1 (from BASF); polyoxypropylene-polyoxyethylene block copolymers available under the tradenames Pluronic L-92, Pluronic L-121 end Pluronic F 68 (from BASF); castor oil ethoxylate available under the tradename Alkasurf CO-40 (from Rhone-Poulenc Mississauga Ontario, Canada); and mixtures thereof.
[0031] Mometasone furoate is slightly soluble in ethanol. As with other drugs which have solubility in ethanol, there is a tendency for mometasone furoate to exhibit crystal growth in ethanol-containing formulations. Formulation parameters which do not promote drug particle size growth are known. These parameters provide the advantage of minimizing the required ethanol concentrations, to reduce the potential for unpleasant taste sensations and render the compositions more suitable for use by children and others with low alcohol tolerance. A certain minimum level of ethanol is preferred to provide consistent and predictable delivery of the drug from a metered dose dispenser. This minimum level is about 1 weight percent of the total formulation, which results in a marginally acceptable drug delivery. Increased amounts of ethanol generally improve drug delivery characteristics.
[0032] However, and to prevent drug crystal growth in the formulation, it is preferred to limit the concentration of ethanol. Experimental data indicate that the ratio of the weight of mometasone furoate to the weight of ethanol is important in preventing particle size increases.
[0033] The available metering valve delivery volumes range from about 25 to about 100 microliters per actuation, while the amounts of drug substance required in a dose for treating a particular condition is generally about 10 to about 500 micrograms per valve actuation. These two factors combined pose limitations that dictate the points within the foregoing ethanol parameters for a given formulation. The determination of such amounts is within the skill of workers in this art.
[0034] Where the active compound forms a suspension, the particle size should be relatively uniform, with substantially all the particles preferably ranging between about 0.1-25 microns, preferably 0.5-10 microns, more preferably 1-5 microns. Particles larger than 25 microns may be held up in the oropharyngeal cavity, while particles smaller than about 0.5 micron preferably are not utilized, since they would be more likely to be exhaled and, therefore, not reach the lungs of the patient.
[0035] The formulations of the present invention may be filled into the aerosol containers using conventional filling equipment. Since propellants 227 and 134 may not be compatible with all elastomeric compounds currently utilized in present aerosol valve assemblies, it may be necessary to substitute other materials, such as white buna rubber, or to utilize excipients and optionally surfactants which mitigate the adverse effects of propellant 227 or 134 on the valve components.
[0036] Depending on the particular application, the container may be charged with a predetermined quantity of formulation for single or multiple dosing. Typically, the container is sized for multiple-dosing, and, therefore it is very important that the formulation delivered is substantially uniform for each dosing. For example, where the formulation is for bronchodilation, the container typically is charged with a sufficient quantity of the formulation for 200 charges.
[0037] Suitable suspensions may be screened in part by observing several physical properties of the formulation, i.e. the rate of particle agglomeration, the size of the agglomerates and the rate of particulate creaming/settling and comparing these to an acceptable standard. Such, suitable solutions may be screened/evaluated by measuring the solubility of the medicament over the entire recommended storage temperature range.
[0038] Suspensions of the present invention preferably may be prepared by either the pressure filling or cold filling procedures known in the art. For metered dose inhalers, suspensions may be particularly preferred for efficacy and stability considerations.
[0039] Those skilled in the art may choose to add one or more preservative, buffer, antioxidant, sweetener and/or flavors or other taste masking agents depending upon the characteristics of the formulation.
[0040] The processes and products produced thereby of the present invention overcome stability problems i.e. crystal growth during compounding/filling encountered while formulating. The addition of the propellant in a single stage quenches crystal growth of the pharmaceutical active, particularly with mometasone furoate anhydrous since the solubility in the concentrate is much greater than that in the final formulation. Suspensions in which a high proportion of drug is dissolved have a tendency to exhibit particle size growth by a phenomena known as Ostwald Ripening.
[0041] Further, the process itself is very robust process and reproducible. The particle size distribution of the product for each batch is reproducible and the fill weight of each ingredient is the same in each canister. Indeed, the particle size of the active is maintained throughout the process, which is very important as the final product is to be administered to patients and uniformity of particle size below 10 microns for inhalation is extremely important. Another added advantage is that of excellent process capability (0.98 correlation coefficient) for PSD as is demonstrated by a good linear relationship of drug substance particle size to drug product particle size. And, it conforms to stringent FDA requirements for both batch to batch and unit to unit within the batch content uniformity, reproducibility, particle size distribution, and drug content uniformity.
[0042] This invention further relates to the improvement in the quality with regards to both particle size uniformity and formulation stability of the mometasone furoate MDI Oral and Nasal Suspension, either alone or combined with other drug substances, e.g. formoterol fumarate, by controlling the particle size of the suspended mometasone furoate drug substance. For mometasone furoate MDI, it has been found that the quality of the drug product is linked to the particle size range of the suspended drug substance. There is a rank order correlation of the quality of the product with a decrease in the size range of the corresponding drug substance suspended in the product. It was determined that drug substance containing a high proportion of large crystals>having a particle size of greater than 10 microns produces a product with unacceptable particle growth with time and temperature. However, it has been found that when the particle size of the drug substance is less tahn 10 microns, a product is produced which has uniform suspended drug particles with a markedly, surprising improved and stable particle size profile with time and temperature.
[0043] In the case of the oral MDI containing mometasone furoate, an example of an acceptable product profile for the 100 microgram per actuation strength, using an Anderson cascade impactor and 1-liter entry port, is given below (for 2 actuations dose):
[0044] Group 1—Entry port+Stage 0=9-14 μg
[0045] Group 2—Stage 1+Stage 2=18-19 μg
[0046] Group 3—Stage 3+Stage 4=131-132 μg
[0047] Group 4—Stage 5−Filter=26-27 μg
[0048] Group 5—Total Drug Recovery=194-198 μg
[0049] % Fine Particles (Stages 3−Filter)=79-82%
[0050] The size of the suspended mometasone furoate drug contained in the drug product may be controlled in the following ways. First, the drug substance may be more efficiently milled prior to product batch manufacture. This could include reducing the micronization feed rate, employing centrifugal classification to remove larger particles and increasing the number of cycles that the material is fed into the micronizer (i.e., double micronizing). Alternatively, The drug substance may be spray dried prior to product batch manufacture (i.e., including super critical fluid technology) to create uniformly small drug substance particles. Also, the method of manufacture can be modified by various methods, i.e., by reducing the temperature of batch manufacture, reducing the level of alcohol used to prepare the drug concentrate, and/or reducing the homogenization time. Finally, other processes of controlling drug substance particle size known in the art, e.g., using surfactants or other particle size growth retardation approaches. This aspect of the invention is not compound specific and does not solely relate to Mometasone Furoate. It also applies to other systems in which a material or materials are suspended in a liquid medium.
[0051] The foregoing descriptions of various embodiments of the invention are representative of various aspects of the invention, and are not intended to be exhaustive or limiting to the precise forms disclosed. Many modifications and variations undoubtedly will occur to those having skill in the art. It is intended that the scope of the invention shall be fully defined solely by the appended claims.
EXAMPLE 1
[0052] The compounding area should preferably be at a room temperature of ≦70° F. and a humidity level of ≦60% RH. The compounding tank should be pressure rated to a minimum of 100 psig and should contain a safety valve that will allow for slow release of contents if the pressure exceeds 100 psig.
[0053] Charge about 90% of the alcohol into a suitable premix vessel. Cool the contents of the premix vessel to 0±5° C. Charge the oleic acid into the premix vessel with homogenization (Silverson, in-dwelling). Rinse the weighing container with the remainder (about 10%) of the alcohol and add the rinses to the premix vessel with homogenization. Homogenize for approximately 5 minutes or until the oleic acid has completely dissolved.
[0054] Charge the micronized mometasone furoate anhydrous, into the premix vessel and homogenize (Silverson, in-dwelling) at high speed for approximately 5 minutes or until a uniform and smooth suspension has formed. Determine the weight of mometasone furote anhydrous left in the container after charging it to the batch. If that weight is greater than 0.5% of the theoretical active batch charge, then add additional active (equivalent to the amount of left on the container) to the batch.
[0055] Next, charge the contents of the premix vessel into the compounding tank. Completely seal the compounding tank. Charge to the sealed tank the HFA 227 that has been filtered through an integrity tested filter, e.g., Aervent cartridge filter from Millipore with teflon encapsulated O-rings.
[0056] Begin agitation with a suitable mixer (propeller mixer) and continue for the duration of the filling operation. Begin circulation of the product through the aerosol-filling machine (Pamasol) and maintain the temperature of the compounding tank at refrigeration (approximately 0±100° C.) for the duration of the filling operation.
[0057] Fit and crimp the valve onto the can. The valve crimp height guideline should be 5.7±0.1 mm (measured by a Socoge gage). The valve crimp diameter guideline is 17.7±0.1 mm (measured by a micrometer). The ranges may vary as is known to one of skill in the art. Measure periodically and make the necessary adjustments to achieve the recommended guideline values. Meter the required weight of product into each can. Check the fill weight of the product periodically and make the necessary adjustments to achieve the in-process control limits.
[0058] Leak test cans upon completion of batch manufacture (at least 1 can in 500) by immersing in a 55-60° C. water bath for 5-10 minutes. The samples that are leak tested should not show leakage or permanent deformation. Discard any part of the batch in which leakage or permanent deformation is observed in this leak test. The leak test was in accordance with 49 CFR 173.306(b) (3)).
[0059] Lagger cans for a minimum of 10 days. Prior to spray testing. Upon completion of laggering, spray test (minimum 3 actuations/can) and check weigh cans according to procedures known in the art.
EXAMPLE 2
[0060] Initially, it was determined that a minimum of 30 psi pressure must be maintained inside the product compounding vessel in order to meet the product fill weight requirements. This pressure is needed for the proper operation of the dual piston Pamasol pump, which transfers the product from the compounding tank to the Pamasol filling machine.
[0061] The 30 psi pressure in the system can be obtained by increasing the temperature of the product vessel to >10° C. This results in evaporation of propellant (i.e., HFA-227) into the headspace of the mixing vessel which becomes more significant during the course of filling operation, i.e., as the headspace in the vessel increases due to the removal of product. Thus, as the propellant concentration decreases, the concentration of the other ingredients in the product correspondingly increase, leading to levels that cannot meet the product specifications.
[0062] In another embodiment of the present invention, one can re-charge propellant into the batch at the point where evaporation is significant enough to affect product quality. This approach adds an additional step to batch manufacture, but also may lead to a less robust process since the levels added are difficult to control and are a time consuming process.
[0063] An alternate means of having 30 psi pressure in the vessel while, at the same time, allowing the temperature to be low enough to avoid evaporation of propellant, is to charge high pressure gases i.e., nitrogen, compressed air, etc., into the product compounding vessel. This approach has many drawbacks as well which include the introduction of increased levels of water in the product, drug degradation for air and moisture sensitive compounds and formation of pockets of trapped gases within the liquid (i.e., air bubbles) which can lead to erratic dose delivery.
[0064] This invention, is a substantial improvement to the current Pamasol one-step filling operation, in that it allows the product to be filled reproducibly at low pressure (<<30 psi) and thus resolves the above issues. In one aspect of the invention, there is the use of a single or dual pump system for the filling of areosol formulations from the compounding tank while maintaining recirculation through the filling lines. These pumps function as follows: A single pump is used when the pressure in the tank is 0 to 10 psi. This pump is available as a Versa-Matic Double DIaphragm pump. An alternate pump is the Versa-Matic Double Diaphragm pump or the Pamasol Double Diaphragm pump for when the pressure is greater than 10 psi yet lower than 15 psi. The sequence of the pumps and the tank in this dual system is critical and should be in the following order. Compounding tank then Versa-Matic Double Diaphragm pump, Pamasol Double Diaphragm pump and finally the Pamasol filler. This aspect of the invention is dictated by the pressure maintaining capability of the two pumps and the pressure requirement for the Pamasol filler.
[0065] Both pump systems, either individually or combined, e.g., the single pump system utilizing the Versa-Matic Double Diaphragm pump, as well as the dual pump system utilizing the Versa-Matic Double Diaphragm Pump and the Pamasol Double Diaphragm pump maintain the pressure greater than 30 psi. This pressure is required by the Pamasol filling machine for reproducible filling in to the aerosol cans as well as for proper recirculation through the filling lines.
[0066] With this new system, the product fill weight requirement is met and the batch yield is >90%.
[0067] Accordingly, in one aspect of the present invention, the following procedure has been carried out. Initially, flush the compounding vessel, the dual piston pump, the Pamasol filler and all lines with Nitrogen for about 15 minutes. Thereafter, evacuate all of the gasses by vacuum. Activate the chiller and set the temperature for about −20 degrees Celsius. Compound an aerosol batch by charging all of the ingredients into a completely sealed aerosol compounding vessel. Begin mixing the ingredients while cooling the product. Open the bottom valve of the compounding vessel and start re-circulating the product through the dual piston pump back to the compounding vessel until the pressure of the compounding vessel is less than or equal to about 5 psi. Stop the pump, and disconnect the return line of the vessel. Connect this line to the inlet of the Pamasol filler and outlet of the pamasol filler connect to the inlet of the compounding vessel. Start re-circulation of the product until the vapor pressure reaches less than or equal to about 3 psi. Fill the 15 ml aerosol cannisters with a fill weight of about 16 g +/−0.3 grams. Check the weight of 10 cans from the beginning, middle and end of the batch.
[0068] The following results were obtained as set forth below.
TABLE 1 Can Net Fill Weight of the Product Beginning of the Middle of the End of the Batch Can Number Batch (g) Batch (g) (g) 1 16.23 16.15 16.09 2 16.17 16.11 16.09 3 16.13 16.13 16.13 4 16.16 16.13 16.12 5 16.13 16.14 16.11 6 16.17 16.10 16.09 7 16.14 16.14 16.10 8 16.16 16.11 16.11 9 16.17 16.11 16.11 10 16.16 16.13 16.12 Average 16.16 16.13 16.11
[0069] Throughout the fill process, the in beginning of the batch the compound vessel was operated at 3 psi and a temperature of −11.1 degrees Celsius, in the middle of the process the compound vessel was operated at 0.5 psi and a temperature of −12.5 degrees Celsius, and in the end of the process the compound vessel was operated at 0 psi and a temperature of −13.3 degrees Celsius.
EXAMPLE 3
[0070] Another aspect of the present invention is defined as a novel method of one-step filling and manufacture/compounding of a dispersion system of a well mixed suspension, e.g. mometasone furoate in ethanol/oleic acid suspension medium to which small amounts of the propellant e.g. HFA-227, HFA-134a, CFC 11.12, 114, are added continuously to a final weight in a pressurized compounding vessel.
[0071] The basis of the invention is the continuous addition of vaporized or liquid propellant compensate and prevent the gradual loss of propellant from the liquid phase to the vapor phase, i.e., evaporation. This evaporation occurs in the course of filling and leads to a gradual increase of the concentration of the active drug substance, mometasone furoate, in the finished product. This loss of propellant is driven by the fact that the composition of liquid and vapor phases is not the same. The vapor becomes richer in the more volatile component (propellant) and therefore, the mole fraction of this more volatile component is higher in the vapor phase while the mole fraction of the propellant in the liquid phase decreases thus increasing the concentration of the active drug substance and the ethanol/oleic acid mixture. The propellant loss leads to a decrease in the final yield of the finished product (up to approximately 30% loss due to unfilled end portions of the suspension). This may require maintaining very low filling temperatures; i.e. cold filling (to reduce evaporation) which leads to added technological and processing difficulties.
[0072] The following approaches can be applied for propellant addition to compensate for evaporative losses: (1) the propellant is maintained at approximately 30° C. and added continuously (as a vapor) to the compounding vessel at a constant rate; (2) the propellant vapor generation can also be achieved by transporting the liquid propellant to a holding depressurized vessel where the liquid propellant is allowed to expand and thus evaporate. The depressurized propellant vapor can then be added to the suspension compounding vessel as specified above; finally (3) the propellant can also be added as a liquid throughout the filling process of the batch manufacture.
[0073] All three approaches result in a suspension that is metered with the Pamasol filling equipment into the individual aerosol cans which were previously crimped with appropriate valves.
[0074] The advantages of this method of manufacture by continuous addition of propellant are the following: (1) the manufacture of MDI (Metered Dose Inhaler) with minimal evaporative losses; (2) a product that exhibits consistent Drug Content Uniformity (“DCU”) throughout the filling process; (3) ease of manufacture, e.g. the need for excessive sampling and DCU testing is obviated; and (4) higher yield of the finished product—up to 30% extra finished product can be filled.
[0075] Accordingly, prepare an aerosol batch in a chilled and sealed compounding tank at a temperature of greater than about 5 degrees Celsius. Fill the vaporized propellant vessel with propellant to about 25% of its capacity, weigh and then heat the vessel to 30 degrees Celsius to vaporize the propellant at a pressure of about 70 psi. Connect the vapor terminal of the vaporized propellant vessel to the batch compounding vessel. Open the valve at the vapor terminal of the vaporized propellant vessel. Open and adjust the regulator valve of the compounding vessel to maintain 30 to 40 psi pressure during the filling operation. Fill the aerosol product on to the 15 ml cannisters. Check the fill weight of the filled cans.
TABLE 2 Can Net Fill Weight of the Product Beginning of the Middle of the End of the Batch Can Number Batch (g) Batch (g) (g) 1 16.01 16.01 16.01 2 16.01 16.01 16.00 3 16.02 16.02 16.01 4 16.01 16.01 16.01 5 16.01 16.02 16.01 6 16.01 16.03 16.02 7 16.02 16.00 16.02 8 16.01 16.01 16.02 9 16.01 16.01 16.01 10 16.01 16.01 16.01 Average 16.01 16.01 16.01
[0076] Further evidence for the absence of HFA-227 evaporation during filling due to the addition of the propellant vapor are the Drug Content Uniformity results obtained from the beginning and the end of the filling run, e.g., about 90%, preferably about 92%
[0077] Next, perform cascade impactor tests using the metered dose inhalers produced above, preferably in accordance with USP reference standards. Cascade Impactor tests were performed utilizing the Anderson Cascade Impactor with a 1-liter entry port as is known to one of skill in the art. This assay demonstrates that as the drug substance median increases, the drug product particle size increases. The correlation of drug substance median with the percentage of fine particles of product is 0.98. The Andersen Cascade Impactor is widely used for measuring the particle size distribution of airborne articles and more specifically pharmaceutical aerosols. The eight stage Andersen Impactor separates the sample into nine size intervals when used with a backup filter after the last impaction stage. The fine particle fraction is defined as the percentage of particles having a particle size of less than 4.7 μm. The fine particle dose is defined as the amount in μg per dose that is less than 4.7 μm in size in each actuation. The μg/shot is the total amount of emitted drug product that exits the metered dose inhaler upon actuation. The particle size distribution of the powder is characterized by mass median aerodynamic diameter (MMAD).
TABLE 3 The following table describes the Andersen Cascade Impactor Results for a 100 μg mometasone furoate per actuation product produced in accordance with the process of the present invention. Drug Drug Drug Substance Product Product Median, μm MMAD, μm % Fine Particles 1.14 2.58 79.2 1.19 2.63 75.6 1.25 2.83 68.1 1.38 3.09 56.8 1.53 3.54 50.3 1.77 4.38 37.6
[0078] [0078] TABLE 4 The following table describes the Andersen Cascade Impactor Results for a 200 μg mometasone furoate per actuation product produced in accordance with the process of the present invention. Drug Drug Drug Substance Product Product Median, μm MMAD, μm % Fine Particles 1.14 2.79 76.8 1.29 3.42 57.6
[0079] [0079] TABLE 5 The following table describes the Andersen Cascade Impactor Results for a 100 μg mometasone furoate per actuation product produced by a two stage process. Cascade Upper Impactor Stage Particle Size % Drug Recovery During Batch Filling or Accessory Limit μm 0 hours 3.5 hours 24 hours 0 10 1.52 ± 0.03 1.60 ± 0.01 3.26 ± 0.36 1 9.0 8.38 ± 0.36 8.79 ± 0.14 19.4 ± 1.09 2 5.8 12.9 ± 0.50 11.8 ± 2.93 18.1 ± 0.43 3 4.7 34.2 ± 0.47 32.0 ± 1.92 25.9 ± 0.25 4 3.3 17.0 ± 0.24 14.5 ± 0.96 6.98 ± 0.17 5 2.1 5.05 ± 0.45 4.49 ± 0.24 3.59 ± 0.19 6 1.1 2.04 ± 0.17 2.00 ± 0.12 1.77 ± 0.16 7 0.65 0.88 ± 0.13 0.93 ± 0.08 0.82 ± 0.13 F 0.43 1.17 ± 0.29 1.19 ± 0.09 1.03 ± 0.26 Entry Port n/a 12.7 ± 1.21 16.0 ± 5.00 14.8 ± 1.86 Casings n/a 4.16 ± 0.45 4.35 ± 0.32 5.03 ± 0.41
[0080] As is evident from a comparison of the particle sizes over time during the filling process, there is a significant variation in the particle size in the early stages of the process relative to the particle size at the end of the filling run. It is very important for the particle size to remain consistent during processing.
TABLE 6 The following table describes the Andersen Cascade Impactor with a 1 liter entry port Results for a 100 μg mometasone furoate per actuation product produced in accordance with the process of the present invention. Cascade Upper Impactor Stage Particle Size % Drug Recovery During Batch Filling or Accessory Limit μm 0 hours 24 hours 48 hours 0 10 1.12 ± 0.11 1.32 ± 0.30 1.28 ± 0.08 1 9.0 5.56 ± 0.09 6.45 ± 1.43 6.23 ± 0.67 2 5.8 9.74 ± 0.14 11.2 ± 1.53 10.9 ± 1.30 3 4.7 35.9 ± 0.83 36.5 ± 1.15 35.6 ± 4.73 4 3.3 23.3 ± 0.16 22.2 ± 1.69 22.1 ± 0.39 5 2.1 7.17 ± 0.33 7.14 ± 0.24 7.08 ± 0.39 6 1.1 2.03 ± 0.21 2.25 ± 0.04 2.08 ± 0.19 7 0.65 0.74 ± 0.10 0.83 ± 0.04 0.78 ± 0.09 F 0.43 1.13 ± 0.27 0.99 ± 0.18 0.90 ± 0.04 Entry Port n/a 9.10 ± 0.33 8.96 ± 2.77 9.94 ± 0.23 Casings n/a 4.00 ± 0.88 4.38 ± 0.35 4.49 ± 0.16
[0081] As is evident from a comparison of particle size over time, there is a significant decrease in the change of the particle size over the course of batch manufacture (e.g., 0 to 48 hours) for the one stage process at compared to changes observed during manufacturing using the two stage fill process. Various entry ports of the Andersen Cascade Impactor may change the particle size distributions provided in the tables as is known to one of skill in the art.
TABLE 7 The following table describes the Andersen Cascade Impactor Results for a 100 μg mometasone furoate per actuation product produced in accordance with the process of the present invention from another batch. Cascade Upper Impactor Stage Particle Size % Drug Recovery During Batch Filling or Accessory Limit μm 0 hours 24 hours 48 hours 0 10 0.80 ± 0.03 0.80 ± 0.07 0.79 ± 0.03 1 9.0 2.76 ± 0.10 2.56 ± 0.01 2.38 ± 0.25 2 5.8 5.07 ± 0.20 5.13 ± 0.24 5.24 ± 0.19 3 4.7 25.7 ± 0.64 25.7 ± 0.89 26.6 ± 0.46 4 3.3 34.4 ± 1.31 33.3 ± 2.71 32.1 ± 2.08 5 2.1 14.1 ± 0.68 12.7 ± 1.43 11.3 ± 1.07 6 1.1 2.68 ± 0.06 2.66 ± 0.17 2.81 ± 0.05 7 0.65 0.90 ± 0.05 0.96 ± 0.15 0.99 ± 0.03 F 0.43 0.86 ± 0.04 0.84 ± 0.03 0.91 ± 0.04 Entry Port n/a 8.95 ± 1.36 8.42 ± 1.13 9.22 ± 3.25 Casings n/a 3.68 ± 0.44 3.72 ± 0.39 3.70 ± 0.58
[0082] Again, as is evident from a comparison of particle size over time, there is a significant decrease in the change of the particle size over the course of batch manufacture (e.g., 0 to 48 hours) for the one stage process at compared to changes observed during manufacturing using the two stage fill process.
TABLE 8 The following describes a summary of the Andersen Cascade Impactor results comparing the groupings of a mometasone furoate 100 μg/actuation Product produced by both the single stage and two stage process. Cascade Upper Impactor Particle Drug μg Stage or Size Limit Recovery Grouping Accessory μm 2-Stage 1-Stage I Entry Port, >10 2.7-56.5 29.4-38.1 Casing II 0-2 4.7-10 29.8-84.7 41.6-46.2 III 3,4 2.1-4.7 57.2-124 91.5-101 IV 5-F <2.1 13.6-24.1 27.5-31.8
[0083] As is evident, the one stage filling process eliminates particle size growth during manufacture in an improved manner over the two stage fill process, thus meeting stringent requirements for maintaining a narrower and reproducible particle size of the drug product. Indeed, with the one stage process there was obtained a tight range of particle size (91.5%-101%) that is very desirable as opposed to the extremely broad range (57.2%-124%) for the formulations produced by the two stage process.
[0084] The foregoing descriptions of various embodiments of the invention are representative of various aspects of the invention, and are not intended to be exhaustive or limiting to the precise forms disclosed. Many modifications and variations undoubtedly will occur to those having skill in the art. It is intended that the scope of the invention shall be fully defined solely by the appended claims.
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Disclosed are methods of introducing a suspension or solution of a medicament, preferably mometasone furoate anhydrous, into a metered dose inhaler container, said container having a valve attached thereto, said method comprising the steps of introducing mometasone furoate anhydrous, a surfactant and a chlorflourocarbon free propellant into a vessel that is held under pressure to form a suspension or solution, circulating said suspension or solution from the vessel through a line which includes a filling head, bringing said filling head into communication with said metered dose inhaler container through said valve of said metered dose inhaler container, introducing a quantity of such suspension or solution into the container from the filling head of the line through said valve of said metered dose inhaler container, withdrawing said filling head from said metered dose inhaler container, and sealing said metered dose inhaler container, as well as the products produced thereby having an improved particle size distribution of the active ingredients in metered dose inhalers.
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FIELD OF THE INVENTION
The present invention relates generally to the locking of implant elements to each other. The invention concerns especially a method for locking two implant elements to each other, such as a plate to a bone screw passed through a plate hole, or a fixing means, such as spinal hook, on a rod-shaped strut or a rod-shaped strut end in a hole or in a sleeve, the one implant element being passed through or inserted into the other implant element and coacting parts of the implant elements being locked or fixed relative to each other by using locking means, and a device for locking two implant elements to each other, of which elements one, such a as bone screw, is passed through a hole in the other, such as a plate or a block, said one element having an end part adapted to be locked in said hole by being affected from the interior of the end part with the aid of locking means, and also a device for locking two implant elements to each other, of which elements one, such as a bone screw or a rod-shaped strut, is passed through or inserted into a hole in the other, such as plate, a spinal hook or a strut mounting, and is locked relative to said other element by using a locking means.
BACKGROUND ART
In connection with orthopedic surgery, different kinds of implant are often used. It is then a matter of fixing the implant to different kinds of bones by means of bone screws which are screwed to the bone through corresponding holes in the implant, and/or locking or fixing different implant parts to each other by means of different types of conventional locking screws which are screwed into one part to be lockingly engaged with the other part.
When using bone screws, it is well known, for locking thereof relative to the implant that is fixed by means of the bone screws, to use special locking screws which are screwed into the slit end or head or main part of the respective bone screws so as to expand the end or main part into locking engagement with the surrounding wall of the implant hole. For the purpose of achieving the necessary expansion there are arranged coacting conical surfaces on the locking and bone screws, the coacting surfaces of which, during axial relative displacement therebetween, cause a radially outwardly directed effect on said end or main part.
Typical constructions of this type are described in e.g. U.S. Pat. No. 4,484,570 and WP 88/03781.
OBJECTS OF THE INVENTION
A main object of the present invention is to provide a method for accomplishing locking of the type mentioned by way of introduction, which is generally applicable in connection with different types of implant elements.
A further object of the invention is to provide locking in a simple and effective manner.
One more object of the invention is to provide locking with an extended and well-distributed locking engagement.
A further object of the invention is to provide locking by utilizing simple means which to a smaller extent than before require specially designed elements, and in particular which do not require conical element surfaces which increase the expense.
SUMMARY OF THE INVENTION
The above-mentioned objects are achieved by a method and by devices having the features stated in the appended claims.
The invention thus is based on the knowledge that a locking effect can be obtained in an advantageous manner by using a locking means made of a material, which has the property, when subjected to compressive forces, of producing at least essentially uniformly distributed forces directed to all sides away from the material. This locking means is so arranged in connection with implant elements that are to be locked to each other that said forces produce a locking pressing action on the implant elements when the locking means in connection with locking is loaded by means of a tightenable tightening element.
The locking means is advantageously tubular or sleeve-shaped, and the loading thereof preferably occurs in an axial direction, such that said forces are obtained in a radial direction essentially perpendicular thereto. As will be immediately appreciated, it will be advantageous according to the invention to operate with generally cylindrical configurations, which means simplified production of implant elements and also a natural adaptation to existing implant constructions.
According to the invention, use is in other words made of a property of the locking means of producing, in local compression thereof, a pressure spreading distributed over the entire locking means, said pressure spreading being similar to a hydraulic effect and resulting in a most efficient and reliable locking effect.
The locking means is advantageously arranged so as to fill, to at least an essential extent, a space intended therefor and to be enclosed therein, a very small amount of compressive effect being required to obtain a "pressure increase" as required, said "pressure increase" producing the intended locking pressing action on the neighboring implant element parts. In practice, it has been found that the "tightening" that is necessary to produce the required "pressure increase" is comparatively much smaller and easier to accomplish than the locking screw tightening that has been required in the previously used constructions. This is an important advantage in the contexts that are here involved.
As a rule, the "pressure increase" is associated with at least some deformation or dimensional change of the locking means and the ensuing adaptation to the associated space, which in many cases may contribute to a better and more reliable locking effect owing to improved form-locking type engagement with neighboring implant element parts. The neighboring implant element parts can advantageously also be treated, for instance to have a rough surface of the like, to produce increased friction or form locking and, thus, improved locking engagement.
According to the invention, it is advantageous to use a locking means made of a polymeric plastic material, which preferably should have very low compressibility. A suitable material is polytetrafluoroethylene, which also has the advantage of having excellent biocompatibility.
Two main aspects of the invention may be distinguished. According to one main aspect, the locking means is arranged in the one implant element, which is adapted to be at least partially expandable outwards, said directed forces resulting in said one implant element being affected outwards into locking engagement with a surrounding second implant element either directly or via a means arranged between the implant elements, for instance a joint insert, allowing that said one implant element is selectively angularly adjustable in relation to the other implant element.
Said one implant element is especially a bone screw, the outwardly directed effect on the bone screw basically being usable in the same manner as in previous bone screw configurations with an inner locking screw. The bone screw advantageously has a cylindrical, slit main or end part with an inner cylindrical bore for receiving the locking means adapted thereto and an associated tightening element. The main or end part of the bone screw preferably has no laterally projecting end flange of such a conventional kind as is intended for engagement with the upper side of e.g. an implant plate, which is to be fixed by screwing by means of the bone screw.
According to the invention, it is, however, advantageous to fix the two implant elements to each other before locking so as to prevent relative motion therebetween in a first direction, but enabling around said direction a rotary motion of the one implant element, especially a bone screw, relative to the other implant element. For such fixing, a snap function can advantageously be utilized, using a projecting annular bead on the one expandable implant element and a matching annular groove on the other implant element or vice versa, alternatively while placing the annular bead or the annular groove on a joint insert arranged between the implant elements. The snap function is rendered possible in a simple manner owing to the possibility of easily reducing the diameter of the implant element (owing to e.g. slitting) temporarily (in any case as long as the locking means has not yet been inserted into the implant element) when inserting the implant element, allowing a space for the annular bead to pass up to and to snap into the annular groove. It will be appreciated that, if the annular bead is arranged on the implant element, it will also be slit.
A joint insert of the type indicated above may advantageously be spherical in a truncated manner, having a spherical circumferential surface and an inner cylindrical hole of a diameter corresponding to the outer diameter of the implant element which is arranged therein. A suitable slitting makes it possible to easily compress the joint insert and arrange it in a corresponding seat having a spherically designed contact surface in the other implant element.
According to said one main aspect of the invention, there is especially provided a device for locking of implant elements to each other, of which elements the one, such as a bone screw, is passed through a hole in the other, such as a plate or block, said one implant element having an end part adapted to be locked in said hole by the end part being affected from inside, said device comprising a sleeve-shaped locking means, the axial direction of which coincides with an axial direction of the end part and which is arranged in a locking space in the form of an inner annular recess in the end part to rest on a lower shoulder therein, and a tightening element adapted to be moved into tightening engagement with said one element while being engaged with the locking means so as to compress the same, the locking means, during tightening of the tightening element, exerting on the circumferential wall parts of the end part an essentially uniform pressure directed radially outwards, thereby causing the wall parts to provide a locking engagement. The locking means can also be pressed out somewhat in slits formed in the end part, which results in improved engagement between the locking means and the end part and, consequently, more reliable locking.
According to a preferred embodiment of the invention, the tightening element is a locking screw which is screwable into said end part and which has an abutment surface, for instance the underside of the screw head, for tightening engagement with the upper end of the locking means, the screw preferably being threadingly engaged with said one element below the lower shoulder and constituting an internal boundary surface of the annular recess for the locking means. The size of the ring- or sleeve-shaped recess may, as is appreciated, very well be adapted to that of the locking means, such that the locking means need be subjected but to little tightening before the recess is completely filled by the material of the locking means and a "pressure increase" causing the locking is obtained.
According to the other main aspect of the invention, the locking means is arranged between the two implant elements that are to be locked to each other, such that said directed forces cause a locking pressing action on locking surfaces, arranged opposite to each other, of the respective implant elements. In this case, use is preferably made of a sleeve-shaped locking means, which is arranged in a corresponding space which is coaxial with at least one of the two implant elements, compressive forces acting in an axial direction of the locking means and the resulting directed forces acting at least essentially perpendicularly thereto.
According to a preferred embodiment, there is provided a device for locking two implant elements to each other, of which elements the one, such as a bone screw or a rod-shaped strut, is passed through or inserted into a hole in the other, such as a plate, a spinal hook or a strut mounting, a sleeve-shaped locking means being arranged in a locking space around the first implant element, one end of the locking means resting on a shoulder on one of said two elements, and a tightening element is adapted to be moved into tightening engagement with one of said two elements while being engaged with the locking means so as to compress the same, the locking means during tightening exerting a pressure, which is directed inwards and outwards at least essentially to all sides, on neighboring parts of said one or other element, thereby locking them relative to each other. The tightening element may easily be given the shape of a sleeve-shaped nut means, which is arranged around the first element and is externally or internally threaded for engagement with a corresponding internal or external thread on the second or the first implant element.
This aspect of the invention implies radically new thinking in connection with the locking of implant elements relative to each other, by not using the locking means to accomplish a locking expansion of one of the implant elements, but instead using the capability of the actual locking means of producing, while changing dimensions to some extent, a highly well-distributed and efficient "pressurized" locking engagement with the respective implant elements. The locking configuration may be very simple in terms of construction, inexpensive and easy to handle, while the locking becomes extremely reliable.
The invention will now be described in more detail by means of embodiments with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic partial part-sectional view of a first embodiment of a device according to the present invention.
FIG. 2 is a schematic partial top plan view of the device in FIG. 1.
FIG. 3 is a schematic partial part-sectional view of a second embodiment of a device according to the present invention.
FIG. 4 illustrates on a larger scale part of the view in FIG. 3.
FIG. 5 is a view of the same kind as in FIG. 4, illustrating a third embodiment of a device according to the invention.
FIG. 6 is a schematic partial part-sectional view of a fourth embodiment of a device according to the invention.
FIG. 7 is a schematic partial top plan view of the device in FIG. 6.
FIG. 8 is a schematic partial part-sectional view of a fifth embodiment of a device according to the invention.
FIG. 9 is a schematic partial part-sectional view of a sixth embodiment of a device according to the invention.
In the Figures, identical or corresponding elements have been given the same reference numerals.
DESCRIPTION OF EMBODIMENTS
FIGS. 1 and 2 illustrate schematically an embodiment of the present invention, an elongate implant plate 1 being shown in coaction with a bone screw 3 intended to be screwed into the bone 2. The bone screw 3 has a practically fully threaded screw part 4 and a circular cylindrical end or main part 5, the diameter of which is increased in relation to the screw part and which is received with good fit in a corresponding circular cylindrical hole 6 in the plate 1. In the embodiment shown, the axial direction of the hole 6 is perpendicular to the plane of the plate 1, but it will easily be appreciated that said axial direction could be inclined in relation to the plate, resulting in angling of the bone screw 3.
The end part 5 has a height that is slightly larger than the thickness of the plate 1, the end part projecting slightly beyond the plate 1, such that the end part is easily accessible for engagement with a suitable tool for rotation of the bone screw, which will be described in more detail below. The end part 5 has no laterally projecting end flange or the like, which is normally to be found on a screw head for engagement with the element that is to be attached by means of the screw.
With a view to holding the plate 1 and the screw 3 together, thereby preventing relative motion therebetween in the axial direction of the screw in connection with the screwing of the screw into or out of the bone 2, the plate 1 is provided with an inwardly directed, essentially V-shaped circumferential annular groove 7 at the top of the wall of the hole 6, and the end part 5 is provided with a correspondingly designed projecting annular bead 8 adapted to the annular groove 7. The annular bead can be snapped into the groove 7, as will be described in more detail below. As will easily be appreciated, a fixing of this kind, which allows relative rotary motion, will permit the joint between plate and screw to be active also without the plate 1 abutting against the bone 2. The nonexistence of such abutment confers essential advantages in terms of adjustability, quicker healing and an eliminated risk of necrosis.
The bone screw 3 has an inner axial bore extending practically to the lower end 9 of the bone screw. The bore comprises a number of parts having a diameter which successively decreases downwards. The bore lower part 11, which comprises that part of the bone screw which is primarily adapted to be screwed into the bone 2 is threaded and adapted to receive the lower threaded part 12 of a tightening or locking screw 13. An intermediate part 15 of the bore has a slightly greater diameter and extends approximately up to the end part 5, where the intermediate part, via an annular shoulder 16 which is perpendicular to the axial direction of the bone screw 3, is connected with an upper bore part 17, the diameter of which is still more increased and which is adapted to receive a sleeve-shaped or tubular locking means 19 made of a polymer material, especially polytetrafluoroethylene. The locking means has an outer diameter equal to the diameter of the bore part 17 and an inner diameter equal to the diameter of the bore part 15. In other words, the locking means 19 has a radial thickness equal to the radial dimension of the annular shoulder 16. The locking means 19 has a height which is slightly smaller than the height of the bore part 17.
The end part 5 is formed with three circumferentially distributed narrow slits 21, 22, 23, extending in the longitudinal direction of the bone screw along the entire height of the bore part 17. As will easily be appreciated, these slits, although narrow, make it possible to easily mount the bone screw 3 in the plate 1 before mounting of the locking means 19 and the locking screw 13, the sections of the end part 5, which are separated by the slits 21, 22, 33, being able to spring back to the necessary extent, thereby allowing the annular bead 8 to snap into the annular groove 7.
The locking screw 13 has a head 25 with a diameter equal to the diameter of the bore part 17, such that the lower annular surface of the head can abut against the upper annular surface of the locking means 19 lowered into the bore part 17. Below the head 25, the locking screw 13 has a first unthreaded cylindrical screw part 27, the diameter of which is equal to the diameter of the bore part 15 and the length of which is slightly greater than the height of the locking means 19. As will be appreciated, the screw part 27 defines together with the wall of the bore part 17, the shoulder 16 and the lower annular surface of the screw head 25 a space which is essentially fully closed (except for the narrow slits 21, 22, 23) and which is completely filled by the essentially incompressible locking means 19. It has been found that this, together with the rest of the adjusted configuration, means that the locking screw 13 need be tightened by applying comparatively little force to achieve excellent locking and excellent stability of the joint. The evenly distributed general pressure increase obtained in said space in connection with tightening and causing the outer circumferential surface of the part 5 to be pressed against the wall of the hole 7 in an extremely efficient manner seems to be of essential significance for this purpose.
In operation, the plate 1 and the bone screw 3 are snapped together either before or in connection with the bone screw being screwed into the bone tissue 2. The bone screw 3 is rotated by means of e.g. a suitably designed tool engaging three recesses 31, 32, 33 which are distributed in the exposed end surface of the end part 5. Such rotation of the bone screw 3 may, as will be appreciated, also take place after mounting of the locking means 19 and the locking screw 13, but before tightening of the locking screw. For tightening of the locking screw 13, a recess 35 in the form of a cross and an associated central bore 36 are arranged in the exposed screw head 25 for cooperation with a correspondingly designed tightening tool.
The rotation of bone screw 3 for screwing it in or out could also take place by means of a tool which is caused to coact with the bore in the bone screw 3, in which case at least the locking screw 13 must, of course, be non-mounted or removed. For instance, the lowermost part 37 of the bore could have e.g. a square or hexagonal shape for engagement with the end of a correspondingly designed spanner inserted in the bore.
For the purpose of improving the engagement between the bone screw 3 and the bone 2, it is possible, when using a bone screw having a deep bore, for instance in accordance with the configuration in FIG. 1, to screw the bone screw into the bone with the bore unfilled in any case to such an extent that a certain inwards deformation of the threaded bone screw part becomes possible owing to the pressure from outside exerted by the bone tissue 2. When the locking screw is then screwed into the bore, a return of the bone screw to the original shape will take place, resulting in improved engagement.
As mentioned above, the shown configuration requires comparatively little tightening to provide satisfactory locking. During tightening, some of the material in the locking means--in dependence on to what small extent the material in the locking means is deformable--may be pressed into the slits 21, 22, 23, resulting in additionally improved engagement.
If additionally improved locking is desirable, one or some of the wall surface of the hole 6, the circumferential surface of the part 5, the wall surface of the bore part 17 and the circumferential surface of the part 27 may be given a suitable friction- or engagement-increasing structure, e.g. roughness, grooves, recesses etc.
FIGS. 3 and 4 illustrate a further embodiment of the invention, in which the plate 1 and bone screw 3, before locking, are arranged to be able to take different relative angular positions by the end part 5 of the bone screw being rotatably fixed to the plate 1. To this end, a preferably metallic joint insert 41 is arranged between the plate 1 and the end part 5 of the bone screw. The joint insert consists of an annular element having an inner circular cylindrical wall surface 43 (corresponding to the wall surface of the hole 6 in FIG. 1) and an outer spherically designed circumferential surface 44. The hole of the plate 1 has a wall surface 45 which is spherically designed in immediate conformity with the circumferential surface 44. The annular element 41 has a height greater than the thickness of the plate 1, thereby ensuring the necessary possibility for the surface 45 to slide up and down the annular circumferential surface 44 in connection with the angling between the plate 1 and the screw 3 (as indicated by means of the double arrow 47).
In order to enable easy arrangement of the annular element 41 in the hole of the plate 1, the annular element is slit in some suitable manner (not shown in detail), whereby the annular element, during mounting, may have its diameter decreased sufficiently to allow easy insertion into the hole of the plate 1.
The end part 5 of the bone screw is fixed to the annular element 41 in the same manner as the end part 5 in FIG. 1 is fixed to the plate 1, i.e. by means of an annular groove 7' arranged at the top and an associated annular bead 8, the annular groove here being formed in the inner circular cylindrical wall surface 43 of the annular element. The locking of the joint takes place in exactly the same manner as in FIG. 1 by using a locking means 19 and a locking screw 13 inside the bone screw. The locking means 19 has in this case been given a greater height so as to extend vertically beyond the annular element 41 both upwards and downwards.
In this embodiment, the bone screw 3 is also of a slightly different design, by having an extended bored main part 5, to which a threaded homogeneous screw part 4 is connected.
FIG. 5 illustrates a modification of the embodiment in FIGS. 3 and 4. The annular element 41 has in its inner circular cylindrical wall surface been formed with a central circumferential recess 51, which is so dimensioned that the annular element 41, when subjected to the pressing action of the end part 5 in connection with locking by tightening of the locking screws 13, tends to be deformed somewhat from the spherical circumferential shape. It has been found that the locking of the joint in this embodiment will thus be further improved.
In an embodiment according to FIG. 5 it may be advantageous to let the wall surface 45 of the plate hole have a radius of curvature which is slightly smaller than the radius of curvature of the circumferential surface 44 of the annular element 41, such that the latter, by tightening of the joint, adjusts to the curve of the wall of the hole by a minor deformation of the annular element (resulting from the arrangement of the recess 51). The deformation of the annular element means that the curve of its circumferential surface increases somewhat by a minor "folding" around the recess 51. This results in extremely good locking of the selected angular position between the plate 1 and the bone screw 3.
It will be realized that in connection with an embodiment having a central recess 51 in the annular element, it would be possible to arrange the annular bead 8 to cooperate with the recess 51, which means that the annular groove 71 can be excluded.
FIG. 6 illustrates one more embodiment of the present invention, which differs from the embodiments described above by the fact that there is no locking force acting from inside on a bone screw 63 which is used to fix a plate 1 having a hole. Instead a sleeve-shaped locking means 69 is arranged between the end part 65 of the bone screw 63 and the corresponding hole 66 of the plate, so as to allow accomplishment of frictional engagement between the end part 5 and the locking means 69 and respectively between the locking means 69 and the wall of the hole of the plate 1. The frictional engagement is accomplished by the locking means 69 being subjected to a compressive tightening effect like in the embodiments in FIGS. 1-5.
Like before, the end part 65 of the bone screw 63 is circular cylindrical, but it has no bore. The hole 66 is also circular cylindrical with a diameter equal to that of the end part 65, increased by the radial thickness of the sleeveshaped locking means 69. The locking means 69 rests on an annular flange 71, which results in a reduction of the diameter of the hole of the plate at the lower opening thereof, the opening of the hole inside the annular flange having a diameter equal to the diameter of the end part 65 which is passed therethrough.
For tightening, i.e. compressive action on the locking means 69, use is made of a circular cylindrical ring nut 73 having an inner diameter equal to the diameter of the end part 65 and an outer diameter corresponding to the diameter of the hole 66. The ring nut is externally threaded for threaded engagement with a thread 75 in the upper part of the hole 66.
The ring or locking nut 73 can thus be screwed into the plate around the end part 65 of the bone screw after arranging the locking means 65 in its associated space which is dimensionally adjusted. The tightening of the locking nut 73, which to this end has a number of tool engagement recesses 77, 78, 79 distributed around its exposed annular end face, results in a pressure increase in the locking means, which is made of the same kind of material as the locking means in FIGS. 1-5, said pressure increase causing the desired frictional engagement. It will be appreciated that the engaging action can be improved by the circumferential surface of the end part 65 and/or the wall of the hole in the plate 1 being given a suitable structure in accordance with that discussed above in connection with the other embodiments.
It will be realized that the joint, if desired, can be assembled before screwing the bone screw 63 into a bone while using a hexagonal tool recess 67 formed in the exposed end face of the end part 65. The locking nut 73 is not tightened more than to allow the joint to stay together while the bone screw 63 can still rotate relative to the plate 1.
For the purpose of accomplishing fixing between the plate and the bone screw of the type afforded by the annular groove and the associated annular bead in the embodiments according to FIGS. 1-5, the end part of the bone screw could be provided with a radially projecting annular flange at its lower part, said annular flange being arranged on the annular flange 71, when the bone screw 63 is inserted into the hole 66 in the plate 1, i.e. before mounting of the locking means 69 and the locking nut 73. To begin with, the locking nut is fastened only to keep the joint together, while retaining the possibility of rotation of the bone screw relative to the plate.
FIG. 8 schematically illustrates one more embodiment of the invention, in which a fixing means 81 in the form of a spinal hook is locked onto a strut 83 by applying the same principle as in FIGS. 6-7. The strut 83 is a circular cylindrical rod and passes through a hole 86 in the fixing part 82 arranged on the hook 81 and corresponding to the plate 1 in FIG. 6. In its lower part, the hole 86 has its diameter decreased, thereby allowing the strut 83 to pass with good fit therethrough while a shoulder 84 for a locking means 89 is formed. At the top, the hole 86 has a thread 85. The locking means 89 and a locking nut 88 correspond to and function in the same manner as the locking means 69 and the locking nut 73 in FIG. 6.
As will be immediately appreciated, the spinal hook 81 can easily be displaced along the strut 83 and rotated around this to the desired engaging position, whereupon it is easily locked in the engaging position by tightening of the locking nut 88.
An advantage of the embodiment in FIG. 8 is that the strut 83 may be bent without any noticeable deterioration of the effective locking. The bend of the strut, however, should be taken into consideration when dimensioning the hole area of which the diameter is increased and the inner diameter of the locking nut. In this case, a suitable enclosure of the locking means 89 can be guaranteed by arranging metal washers on both sides of the locking means.
Finally, FIG. 9 illustrates schematically an example of how two struts 83 can be interconnected by applying the same principle as in FIGS. 6-8. The ends of the strut are each inserted into a circular cylindrical recess 96 in a connecting body 91. Each strut end is locked in the associated recess with the aid of a locking means 89 and a locking nut 88 in the same fashion as in FIGS. 6-8.
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A method and a device for locking two implant elements to each other. A sleeve-shaped locking means (19) made of a polymeric material is arranged in a space adapted thereto inside the one element (3) which is placed in a corresponding hole (6) in the other element (1), alternatively between the two elements. The locking means (19) is subjected to compressive tightening, such that the resulting "pressure increase" in the means yields a locking effect on the elements (1, 3).
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FIELD OF THE INVENTION
The present invention relates to integrated circuits and more particularly to a variation-compensated bias current generator.
BACKGROUND OF THE INVENTION
FIG. 1 shows a bias current generator 100 that can be used in a current mirror circuit. As illustrated, a power supply (not shown) is coupled to a source lead 105 of a p-channel transistor 110. A gate lead 115 and a drain lead 120 of transistor 110 are coupled together via a lead 125. Transistor 110 functions as a diode in this arrangement. Drain lead 120 is coupled to a resistor 130, which is coupled to a reference voltage supply 140 via a lead 135.
Current generator 100 operates by having a power supply voltage V DD applied to source lead 105. This causes a current I 110 through transistor 110 and a voltage drop V 110 across transistor 110. Since transistor 110 is in saturation, voltage drop V 110 will be a function of current I 110 . The voltage at node 145 (V 145 ) will be constant due to this voltage drop, and equal to V DD -V 110 .
All of current I 110 is applied to resistor 130 to cause a voltage drop across resistor 130 (V 130 ) equal to I 110 ×R 130 . Yet I 110 ×R 130 must equal the constant voltage V 145 (V DD -V 110 ) at node 145. Any variation of the voltage V 145 will be applied through lead 125 to gate lead 115 to adjust the "turn-on" level of transistor 110. As a result, current I 110 will change so that, eventually, I 110 ×R 130 equals the voltage at node 145. Hence, a constant current source is provided.
The operation of current generator 100 discussed above is ideal. In other words, variations in power supply voltage, temperature or the fabrication processes will cause current generator 100 to provide different current amounts. In particular, one disadvantage of current generator 100 is that the voltage from a power supply (e.g., V DD ), the temperature or the process variations can cause as much as a threefold change in the value of current I 110 . This can cause inconsistent and possibly erroneous operation of a circuit that utilizes current generator 100.
For example, a device including current generator 100 may be used in an environment where the power supply voltage is susceptible to noise. This noise will alter the current provided by current generator 100. Also, that device may be used in applications where the ambient temperatures can be between minus 55° C. to positive 125° C. These temperature variations can cause a change in the current provided by current generator 100, which can have an adverse affect on device performance.
To illustrate, the operation of current generator 100 will be explained for two ambient temperatures. For temperature 1, a steady-state current I 110 ' will be generated. For a temperature 2 that is greater than temperature 1, the resistance of transistor 110 will increase. As a result, the current I 110 will decrease, causing the voltage V 145 to decrease. The decreased voltage V 145 will be applied to the gate of transistor 110 to turn that transistor on harder. Current I 110 will then increase, but still be less than the steady-state current I 110 '. Thus, a constant current will not be generated over a range of temperature variations.
A band gap circuit-based current source can be used to overcome this disadvantage. One such circuit is disclosed in U.S. Pat. No. 5,629,611 to McIntyre entitled "CURRENT GENERATOR CIRCUIT FOR GENERATING SUBSTANTIALLY CONSTANT CURRENT." The drawback to such current source is that it is a physically large circuit due to its use of many circuit elements. See FIG. 2 in the referenced patent. This is unacceptable since silicon area of integrated circuits is costly.
A need exists for a device that will provide a substantially constant current source or sink despite voltage, temperature and process variations. The present invention meets this need.
SUMMARY OF THE INVENTION
The present invention includes at least two variable-resistive devices, such as transistors, coupled to a resistive device, such as a resistor. The transistors are configured so that feedback voltage generated by respective currents of the transistors is applied to the gate of at least one of the transistors. The electrical characteristics of the other transistor changes proportionately greater than the characteristics of the one transistor. With this configuration, a variation-compensated current device is provided.
Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings in which details of the invention are fully and completely disclosed as a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings,
FIG. 1 is a schematic of a current source;
FIG. 2 is a schematic of an embodiment of a variation-compensated current source according to the present invention; and
FIG. 3 is a schematic of another embodiment of the variation-compensated current source according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will be described herein in detail specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not to be limited to the specific embodiments described.
FIG. 2 illustrates an embodiment of the present invention. A variation-compensated bias current generator (VCBCG) 200 includes current generator 100 of FIG. 1. VCBCG 200 also includes a source lead 205 coupled to a source of a p-channel transistor 210. A gate and a drain of p-channel transistor 210 are coupled together at node 245 by a gate lead 215 and a drain lead 220. A source lead 225 is coupled to node 245 and a source of a p-channel transistor 230. A gate of transistor 230 is coupled to reference voltage supply 140 via a gate lead 235. A drain of p-channel transistor 230 is coupled to a resistor 250 via a lead 255. Resistor 250 is coupled to a node 275 via a lead 265. Node 275 is coupled to node 145 and resistor 130 as shown.
It is preferred that the channel length of transistor 210 is a minimum compared to the non-minimum channel length of transistor 110. The effect of this minimum length is that transistor 210 will have greater changes in its electrical parameters or characteristics than transistor 110 when the power, temperature or process varies. In this manner, transistor 210 can compensate for the changes in the electrical parameters characteristics of transistor 110 due to those variations.
In steady-state operation, current I 210 equals current I 230 . The current through resistor 130 equals I 110 +I 210 . The voltage at node 275 (V 275 ) then equals R 130 ×(I 110 +I 210 ). Voltage V 275 is applied to the gate of transistor 110 through lead 125, which feedback maintains I 110 . The voltage at node 245 (V 245 ) equals V 275 +(I 210 ×R 250 )+V 230 , where V 230 is the voltage drop caused by transistor 230. Since the gate of transistor 230 is coupled to ground, transistor 230 is "fully" turned on and will have a minimal voltage drop. The voltage V 245 is applied to the gate of transistor 210 to maintain current I 210 .
In variation-compensation operation, a temperature variation example will be explained. If the ambient temperature for bias current generator 200 increases, then the resistance of transistors 110 and 210 increase to cause a decrease in currents I 110 and I 210 . The decreased currents cause less current to flow through resistor 130, thus causing decreased voltages V 275 and V 245 . These decreased voltages will be applied directly to the gates of transistors 110 and 210, respectively, which will cause those transistors to turn on harder. This in turn will cause currents I 110 and I 210 to increase.
It should be noted that since the electrical characteristics of transistor 210 change proportionately greater than the characteristics of transistor 110, current I 210 will decrease proportionately greater than current I 110 . The current through resistor 130 will change proportionately greater than the change in current I 110 . Accordingly, the voltage V 145 at node 145 will decrease proportionately more under the influence of current I 210 than if only current I 110 were supplied. Thus, the proportionately greater decreased voltage V 145 at node 145 will cause transistor 110 to turn on even harder, thus increasing current I 110 more than if current I 210 was not provided.
It should be noted that the FIG. 2 circuit will also better compensate for voltage and process variations than the FIG. 1 circuit. Furthermore, although variation-compensation block 290 (shown as dashed lines) in FIG. 2 includes transistors 210 and 230, and resistor 250, transistor 210 can be used by itself to compensate for those variations. Transistor 230 is optional to provide an increased voltage at node 245. Resistor 250 is optionally included to compensate for characteristic variations of resistor 130. To this end, the electrical characteristics of resistor 250 preferably will change greater in proportion to variations than will the characteristics of resistor 130.
Generally, variation-compensation block 290 provides a function that compensates for the electrical characteristic changes of transistor 110 caused by variations such as voltage, temperature or process. This is preferably accomplished by providing a device or circuitry in block 290 that changes electrical characteristics proportionately greater than transistor 110.
FIG. 3 shows another embodiment of the present invention. A constant current sink 300 includes a resistor 310 coupled to a power supply (not shown) via a lead 305. Resistor 310 is also coupled to a node 320 via a lead 315. Node 320 is coupled to a drain of a n-channel transistor 330 via a lead 325. A gate of transistor 330 is coupled to the drain of transistor 330 via lead355. Lead 345 is coupled to a reference voltage supply 360 and the source of transistor 330.
A variation-compensation block 390 includes a resistor 370 coupled to node 320 via a lead 375. Resistor 370 is also coupled to a drain of a transistor 380 via a lead 385. A gate of a n-channel transistor 380 is coupled to the power supply (not shown) via a lead 395. A source of transistor 380 is coupled to a drain of a transistor 398 via a lead 397. A gate and a drain of a n-channel transistor 398 are coupled together via lead 399. Lead 393 couples the source of transistor 398 to reference voltage supply 360. One skilled in the art shall recognize that current sink 300 operates similarly to current generator 200 of FIG. 2.
One skilled in the art shall also recognize that transistors 110, 210, 330 and 398 are current devices. In particular, transistors 110 and 210 are current sources. Transistors 330 and 398 are current sinks. In addition, transistors 110, 210, 330 and 398 function as voltage-controlled variable resistance devices. The preferred dimensions of transistor 110 are 10 μm/3 μm. The preferred dimensions of transistor 210 are 10 μm/0.6 μm. The preferred dimensions of transistor 230 are 1.5 μm/0.6 μm. The resistive values of resistors 130 and 250 are preferably 50 kΩ and 10 kΩ, respectively.
Numerous variations and modifications of the embodiment described above may be effected without departing from the spirit and scope of the novel features of the invention. It is to be understood that no limitations with respect to the specific device illustrated herein are intended or should be inferred. It is, of course, intended to cover by the appended claims all such modifications as fall within the scope of the claims.
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The present invention includes at least two variable-resistive devices, such as transistors, coupled to a resistive device, such as a resistor. The transistors are configured so that feedback voltage generated by respective currents of the transistors is applied to the gate of at least one of the transistors. The electrical characteristics of the other transistor changes proportionately greater than the characteristics of the one transistor. With this configuration, a variation-compensated current device is provided.
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FIELD OF THE INVENTION
The present invention relates to fuel injectors, specifically, fuel injectors which spray fuel in a cone-shaped spray at a bent angle to a longitudinal axis of the fuel injector.
BACKGROUND OF INVENTION
Prior art fuel injectors include a discharge end which sprays fuel at an angle oblique to a longitudinal axis of the injector. One design includes a discharge channel which extends along the longitudinal axis, but has a discharge end face which is oblique to the longitudinal axis. This design produces a spray pattern which sprays fuel at an angle oblique to the longitudinal axis of the injector, but is elliptical in shape.
It is believed that another design of fuel injectors includes a discharge channel which is at an angle oblique to the longitudinal axis and has a discharge face which is generally perpendicular to the discharge channel. The discharge face includes a circular exit orifice for discharging the fuel. However, the fuel can be discharged only at the angle of the discharge channel relative to the longitudinal axis. If a user requires a different spray angle, a different injector having the discharge channel at the different spray angle must be used, requiring a significant amount of tooling.
It would be desirable to have a fuel injector which discharges fuel at an angle oblique to the longitudinal axis of the injector, but discharges a circular spray of fuel from the injector, and can be manufactured to discharge the circular spray at one of a variety of desired angles.
SUMMARY OF THE INVENTION
Briefly, the present invention discloses an injector having a downstream end and a longitudinal axis extending therethrough. The injector comprising an outlet orifice located at the downstream end. The outlet orifice has an outlet axis oblique to the longitudinal axis. The outlet orifice discharges a cone-shaped spray having a spray axis co-linear with the outlet axis.
The present invention is also a valve seat for a fuel injector. The fuel injector comprises a longitudinal injector axis extending therethrough. The fuel injector also includes an upstream end having a fuel entrance orifice on the longitudinal injector axis and a downstream end having a fuel exit orifice. The fuel injector also includes a channel extending between the fuel entrance orifice and the fuel exit orifice. The fuel exit orifice has a channel axis oblique to the longitudinal injector axis. Fuel exiting the fuel exit orifice forms a symmetrical cone-shaped spray having a spray axis co-linear with the channel axis.
Further, the invention is a valve seat assembly for a fuel injector. The valve seat assembly comprises a valve seat and a bent stream insert. The valve seat includes a longitudinal axis extending therethrough, an upstream end having a seat entrance orifice on the longitudinal axis, and a downstream end having a seat exit orifice on the longitudinal axis. The valve seat also includes a seat channel extending between the seat entrance orifice and the seat exit orifice along the longitudinal axis and a recessed opening downstream of the seat exit orifice along the longitudinal axis. The recessed opening is larger than the seat exit orifice. The bent stream insert includes an upstream insert end having an insert entrance orifice, a downstream insert end, and a channel axis extending therethrough. The bent stream insert also includes an insert channel having an insert exit orifice at the downstream insert end, the outlet orifice having a channel axis oblique to the longitudinal injector axis and an insert projection extending from the upstream end. The insert projection is adapted to be retained in the recessed opening. The seat exit orifice is in fluid communication with the insert entrance orifice. The channel axis is at a first angle oblique to the seat axis.
The present invention is also a method of generating a cone-shaped bent spray from a fuel injector. The method comprises the steps of directing fuel into an entrance orifice in a valve seat, the entrance orifice being along a longitudinal axis of the fuel injector; directing the fuel from the entrance orifice, through a channel in the valve seat, and to an exit orifice, the channel being along a channel axis at an angle oblique to the longitudinal axis; and discharging the fuel from the exit orifice, the fuel forming a coneshaped spray having a spray axis co-linear with the channel axis.
Additionally, the present invention is a method of changing a fuel spray angle in a fuel injector comprising the step of substituting the first bent stream insert from a discharge end of a fuel injector, the first bent stream insert having a first spray angle, for a second bent stream insert into the discharge end of the fuel injector, the second bent stream insert having a second spray angle.
Further, the present invention is a method of providing multiple bent sprays from a single injector assembly comprising the steps of providing an injector having a discharge end, the discharge end being adapted to receive one of a plurality of inserts, each insert having a different pre-determined angle of discharge; selecting an insert with a pre-determined angle of discharge; and fixedly inserting the insert into the discharge end of the injector.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate the presently preferred embodiments of the invention, and, together with the general description given above and the detailed description given below, serve to explain features of the invention. In the drawings:
FIG. 1 is a side view, in section, of a fuel injector with a valve seat according to a first embodiment of the present invention;
FIG. 2 is a bottom plan view of the valve seat taken along line 2 — 2 of FIG. 1;
FIG. 3 is a bottom plan view of the fuel spray pattern taken along line 3 — 3 of FIG. 1; and
FIG. 4 is a side view, in section, of a valve seat according to a second embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A fuel injector 10 to which the present invention can be applied is disclosed by U.S. Pat. No. 5,875,972, which is owned by the assignee of the present invention and is incorporated herein by reference. In the drawings, like numerals are used to indicate like elements throughout. Referring to FIG. 1, the fuel injector 10 has a downstream end 102 and includes a housing 20 having a longitudinal axis 270 extending therethrough, a valve seat 30 , and a needle 40 . The injector 10 includes an outlet orifice or opening, generally indicated as 104 , located at the downstream end 102 .
A first embodiment of the present invention is shown in FIG. 1 . The valve seat 30 of the injector 10 includes an upstream end 302 , a downstream end 304 , and a beveled surface 310 for seating a sealing surface 402 on a downstream end 404 of the needle 40 . The beveled surface 310 also forms a transition cone 312 , centered around the longitudinal axis 270 , which directs fuel into a channel 320 which extends from the transition cone 312 to the downstream end 304 . An upstream end 322 of the channel 320 has a generally circular fuel entrance orifice 323 and is generally concentrically aligned with the transition cone 312 and the longitudinal axis 270 . The positioning of the upstream end 322 of the channel 320 with the longitudinal axis 270 provides for a round entrance to the channel 320 and helps to maintain a constant tangential velocity from a swirl disc (not shown).
A downstream end 324 of the channel 320 has a generally circular fuel exit orifice 325 . Preferably, the fuel exit orifice 325 is the same as the outlet orifice 104 , although those skilled in the art will recognize that the outlet orifice 104 can be located in another element of the fuel injector 10 , such as a metering orifice (not shown). The downstream end 324 is offset from the longitudinal axis 270 , forming the channel 320 at an angle Φ generally oblique to the longitudinal axis 270 . As shown in FIG. 1, the channel 320 has a longitudinal channel axis 326 at an angle of approximately 10° oblique to the longitudinal axis 270 , although those skilled in the art will recognize that the channel axis 326 can be at an angle of less than 10° or up to 30° with respect to the longitudinal axis 270 . The ability to select different angles allows for greater flexibility for different applications.
The downstream end 304 of the valve seat 30 includes a generally spherical surface or projection 330 . The fuel exit orifice 325 is located on the spherical projection 330 . As shown in FIG. 2, the spherical projection 330 allows for a round fuel exit orifice 325 with a sharp edge at the downstream end 324 of the channel 320 . The sharp edge at the exit orifice 325 maximizes flow turbulence at the exit orifice 325 and maintains a symmetrical cone-shaped spray. The sharp edge also provides an added benefit of reducing build up of deposits at the exit orifice 325 . Fuel exiting from the fuel exit orifice 325 at the downstream end 324 forms a generally symmetrical right circular cone C, which exits the valve seat 30 at along a cone axis 328 which is generally co-linear with the channel axis 326 , as shown in FIGS. 1 and 3.
Preferably, the valve seat 30 is constructed from 440C hardened stainless steel, although those skilled in the art will recognize that the valve seat 30 can be constructed of other, similar materials. The valve seat 30 can be heat treated by hardening, deep freezing and tempering to RC 55-60. To form the channel 320 in the valve seat 30 , a laser drilling process is preferred, although those skilled in the art will recognize that other, suitable methods can be used.
In a second embodiment, shown in FIG. 4, the one-piece valve seat 30 of the first embodiment can be replaced by a two-piece valve assembly 100 comprising a valve seat 50 and a first bent stream insert 60 , with the longitudinal axis 270 extending therethrough. The valve seat 50 includes an upstream end 502 , a downstream end 504 and a beveled surface 510 for seating the sealing surface 402 on the downstream end 404 of the needle 40 . The beveled surface 510 also forms a transition cone 512 , which directs fuel into a channel 520 which extends between the transition cone 512 and the downstream end 504 along the longitudinal axis 270 . An upstream end 522 of the channel 520 includes a seat entrance orifice 523 and a downstream end 524 includes a seat exit orifice 525 , with both the seat entrance orifice 523 and the seat exit orifice 525 being on the longitudinal axis 270 . The valve seat 50 also includes a recessed opening or enlarged bore 530 downstream of the seat exit orifice 525 along the longitudinal axis 270 for accepting and retaining an insert projection 606 of the insert 60 in the bore 530 as will be discussed later herein. The bore 530 is larger than the seat exit orifice 525 so that the insert 60 can be inserted into the bore 530 without restricting flow from the seat exit orifice 525 .
An upstream end 602 of the insert 60 includes an insert projection 606 which is adapted to be retained in the bore 530 . A downstream end 604 of the insert 60 includes a spherical portion 610 . An insert channel 620 having an insert entrance orifice 623 and an insert exit orifice 625 extends along a channel axis 626 through the projection 60 , between the insert entrance orifice 623 in the upstream end 602 and the insert exit orifice 625 in the downstream end 604 .
The insert entrance orifice 623 of the channel 620 is generally concentrically aligned with the transition cone 512 and the longitudinal axis 270 so that the insert entrance orifice 623 at the upstream end 622 of the channel 620 is fluidly connected to the seat exit orifice 525 in the seat 50 . However, the insert exit orifice 625 is offset from the longitudinal axis 270 , forming the channel 620 generally oblique to the longitudinal axis 270 . As shown in FIG. 4, the channel axis 626 is at an angle Φ of approximately 10° oblique to the longitudinal axis 270 , although those skilled in the art will recognize that the channel 620 can be at an angle less than 10° or up to 30° with respect to the longitudinal axis 270 .
Fuel exiting from the insert exit orifice 625 forms a generally symmetric right circular cone-shaped spray C 1 , which exits the insert 60 at along a cone axis 628 which is generally co-linear with the channel axis 626 , as shown in FIG. 4 .
To construct the valve seat assembly 100 , the projection 606 of the insert 60 is inserted into the enlarged bore 530 in the seat 50 . Preferably, the seat 50 and the insert 60 are laser welded together, although those skilled in the art will recognize that the seat 50 and the insert 60 can be connected by other means, including press fit.
The seat 50 and insert 60 , when the projection 606 of the insert 60 is inserted into the enlarged bore 530 in the seat 50 , operates in the same manner as the first embodiment valve seat 30 described above. A benefit of the second embodiment over the first embodiment is that, with a separate seat 50 and insert 60 , different materials can be used as desired. Preferably, the seat 50 is constructed from 440C stainless steel and the insert in constructed from 304 stainless steel, although those skilled in the art will recognize that the seat 50 and the insert 60 can be constructed of other materials, including but not limited to Fecralloy (iron-chrome-aluminum alloy) or ceramic material to reduce injector deposits. Additionally, the two-piece design allows the seat 50 to be a permanent part of the injector 10 , but allows for a second insert constructed from a different material and/or having a different pre-determined angle Φ to be substituted for the first insert 60 for different applications or requirements. Further, the two-piece assembly 100 also allows for more simplicity in the assembly process since the insert 60 can be inserted into the seat 50 at the end of the assembly line, minimizing the need for tooling changes, and an insert 60 having a particular pre-determined angle D can be used, depending upon customer needs.
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.
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An injector for high pressure direct fuel injection in an internal combustion engine is disclosed. The injector has a downstream end and a longitudinal axis extending therethrough. The injector has an outlet orifice located at the downstream end. The outlet orifice has an outlet axis oblique to the longitudinal axis. The outlet orifice discharges a circular cone-shaped spray having a spray axis co-linear with the outlet axis. A method of forming a bent circular cone-shaped spray pattern is also disclosed.
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BACKGROUND OF THE INVENTION
The present invention relates to the general technical field of cooking appliances having a vessel, or tank, provided to receive a cooking bath. The present invention concerns more particularly appliances of the type mentioned above having a device for emptying the cooking bath contained in the vessel.
The present invention concerns particularly, but not exclusively, fryers. In effect, a cooking bath is not limited to a bath of oil or of melted fat, but can equally consist of any edible material that is sufficiently fluid to flow through an emptying device, and particularly a water-based liquid.
The patent documents U.S. Pat. No. 2,597,695, CH 325786 and FR 2665068 disclose fryers having an emptying conduit. However, none of them provides for a receptacle for collecting cooking liquid. The patent document FR 2773976 describes a fryer having an emptying conduit and a receptacle supported by a drawer mounted in the housing of the appliance. The utilization of such appliances requires careful attention on the part of the user with regard to the emptying of cooking liquid out of the housing.
The U.S. Pat. No. 2,867,164 describes a fryer of the industrial type having a vessel and an emptying receptacle housed in a frame. The vessel has an emptying conduit closed by a gate, or valve. The emptying receptacle is mounted in a removable manner on the inner face of a door of the frame. The transposition of such a form of construction into a household appliance appears to present safety issues.
BRIEF SUMMARY OF THE INVENTION
An object of the present invention is to increase the security of cooking appliances having a vessel provided with an emptying device.
Another object of the invention is to improve the convenience of use of cooking appliances having a vessel provided with an emptying device.
An additional object of the invention is to provide an appliance of the type described above having a simple structure.
Yet another object of the invention is to provide an appliance of the above-described type having a compact structure.
These objects are achieved with a cooking appliance comprising: (a) a housing; (b) a vessel provided to be placed in the housing and arranged to receive a cooking bath; (c) an emptying device provided in the vessel for permitting the cooking bath to be drained from the vessel; (d) an emptying receptacle for receiving the cooking bath from the vessel via the emptying device; (e) a first valve associated with the emptying device; (f) a maneuvering button associated with the emptying device; and (g) a control mechanism mounted on the emptying receptacle and interposed between the maneuvering button and the first valve for moving the first valve between open and closed positions in response to movements of the maneuvering button; (h) wherein the emptying receptacle is removable from the housing.
The cooking appliance according to the present invention assures that, in the absence of the emptying receptacle, there is no risk that the user can proceed to empty the appliance. In addition, by the fact that the control mechanism is mounted on the emptying receptacle, the vessel can be removable with respect to the housing, and can thus be placed in a washing machine. The emptying receptacle can be disposed in the housing or can form a base on which the housing rests.
Advantageously, the maneuvering button is mounted on the emptying receptacle. This arrangement permits a structural simplification. Alternatively, the maneuvering button can, for example, be mounted on the housing.
Advantageously, the housing has a lateral opening into which the emptying receptacle can be at least partially inserted. This arrangement permits handling of the emptying receptacle to be facilitated. Alternatively, the housing can for example be made of two parts, an upper part at least partially surrounding the vessel, and a lower part supporting the emptying receptacle, the upper part being able to be withdrawn to permit access to the emptying receptacle.
Advantageously then, the maneuvering button is mounted on an outside lateral face of the emptying receptacle. This arrangement permits a structural simplification. Alternatively, the maneuvering button can, for example, be accessible through a hatch, or door, provided on a face of the housing.
According to one embodiment, the control mechanism has a cam provided to cooperate with the valve. Such a form of construction is simple and reliable.
Advantageously, the cam is carried by a movable control piece mounted on an inlet conduit communicating with the emptying receptacle, the movable control piece having a funnel provided to supply a filling opening of the inlet conduit when the cam opens the valve. Such a form of construction permits the number of parts to be limited.
Advantageously then, the movable control piece is driven in rotation by the maneuvering button. Such a form of construction is particularly simple and reliable.
Also advantageously, the cam is arranged above the funnel. This arrangement permits a particularly compact control mechanism to be created.
Also advantageously, the control mechanism has a bolt, or latch, provided to cooperate with a striking plate belonging to the valve when the valve is brought to its open position. This arrangement permits the emptying receptacle to be bolted, or latched, in order to prevent withdrawal of the receptacle from the housing during an emptying operation.
According to one advantageous form of construction, the bolt is formed by a lateral face of the cam, which permits the structure to be further simplified.
According to a further advantageous form of construction, the striking plate is formed by a longitudinal slot provided at the lower end of a conduit in which is housed a movable blocking piece of the valve, which is displaced by the cam. This arrangement also permits the structure to be simplified.
Also advantageously, the appliance is provided with a movable safety piece that has a first cam provided to be driven by the control mechanism when the maneuvering button is operated to open the valve, a second cam provided to be driven by the control mechanism when the maneuvering button is then moved to close the valve, and a blocking abutment provided to block the control mechanism in order to prevent opening of the valve. This arrangement prevents the occurrence of a renewed emptying of the vessel if the emptying receptacle has first been withdrawn at least partially from the housing, and then put back in place, after a first emptying, or in other words if the emptying receptacle has not been manipulated in such a manner as to indicate that it has been emptied.
Advantageously then, the movable safety piece is pushed back by the emptying receptacle, through the intermediary of a flexible blade, when the receptacle is replaced in the housing, the flexible blade being moved aside when the movable safety piece reaches a stopping abutment. This arrangement assures, in a simple manner, the proper positioning of the safety piece during installation, or reinstallation of the receptacle into the housing.
According to an advantageous form of construction, the emptying device has a thermostatic valve. This permits the safety of the appliance to be further improved and also allows the use of less durable, and thus less costly, materials for the emptying receptacle and/or the control mechanism.
According to another advantageous form of construction, a filter is arranged upstream of the emptying device. This arrangement prevents residues present in the cooking bath from adversely affecting the operation of the emptying device. This arrangement also permits the quality of the cooking bath to be improved when successive batches of food are fried with the same bath.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of one embodiment of a cooking appliance according to the invention, in a position provided for emptying the contents of the vessel, or tank, with the exterior housing being shown in broken lines.
FIG. 2 is a perspective view of a portion of the appliance of FIG. 1, in a position after emptying of the vessel, showing the safety device provided to prevent successive emptyings without at least partial withdrawal of the emptying receptacle.
FIG. 3 is an elevational, cross-sectional detail view of the appliance of FIG. 1, in a position after emptying of the vessel.
FIG. 4 is a view similar to that of FIG. 3 showing the appliance in the position provided for emptying the contents of the vessel.
FIG. 5 is an elevational view, partly in cross-section, showing the emptying receptacle as it is being put back in place in the housing.
FIG. 6 is a perspective, detail view of the emptying receptacle after it has been put back in place in the housing and before a new emptying operation.
DETAILED DESCRIPTION OF THE INVENTION
The appliance shown in FIGS. 1-6 is a fryer having a housing 1 provided with an upper opening for receiving a vessel, or tank, 2 that is intended to hold a cooking liquid. The upper opening can be closed by a lid (not shown). Housing 1 also has a lateral opening for introduction and removal of an emptying receptacle 3 .
As shown most clearly in FIGS. 3 and 4, vessel 2 is provided with an emptying device 10 . Vessel 2 is advantageously removable from housing 1 and is provided with means, such as feet 8 , which enable vessel 2 to be placed on a working surface. If desired, electric heating means 9 can be fixed under vessel 2 . Alternatively, the electric heating means can be arranged in housing 1 or even within vessel 2 .
Emptying device 10 comprises an evacuation conduit 15 that extends from the bottom of vessel 2 . A filter 14 can be placed above the inlet end of conduit 15 in order to protect the conduit. A spring-loaded valve 20 is installed to close the bottom of conduit 15 and a thermostatic valve 16 is provided in conduit 15 between filter 14 and valve 20 .
Conduit 15 is constituted by a body 11 that is preferably made of a plastic that is sufficiently resistant to the elevated temperatures that can arise in a cooking bath, preferably a plastic that is able to resist temperatures as high as 250° C., one such plastic material being sold under the trade name Amodel. Body 11 is installed to be removable from vessel 2 . A seal, or joint, 19 is interposed between vessel 2 and body 11 . Joint 19 is advantageously secured to body 11 in order to avoid being lost during removal of the emptying device and to assure that the joint will not be forgotten when the emptying device is reinstalled.
Filter 14 is mounted to be removable from vessel 2 and body 11 . According to the exemplary embodiment shown in the drawing, filter 14 is secured to a ring 13 constructed to form a bayonet attachment with body 11 . Ring 13 is housed in a removable manner in a recess in the bottom of vessel 2 . Ring 13 is prevented from rotation with respect to vessel 2 . The upper part of body 11 is engaged in an opening formed in the bottom of vessel 2 , and is provided with ramps 11 a that cooperate with ramps 13 a of ring 13 to form the bayonet assembly.
Thermostatic valve 16 includes a bimetallic disk 17 , preferably of the snap-action type, fixed to the lower face of a perforated plate 18 that extends across the upper end of body 11 . Plate 18 is, for example, crimped to the interior of body 11 .
Disk 17 is shown in FIGS. 3 and 4 in the position in which valve 16 is opened, this corresponding to the low temperature position. When disk 17 is in the high temperature position, it closes conduit 15 by coming to bear against an internal annular shoulder 12 of body 11 . The transition temperature between the high temperature position and the low temperature position during cooling of disk 17 is, for example, of the order of 90° C. in the case of a fryer.
The spring-loaded valve 20 includes a movable blocking piece 21 equipped with a peripheral toroidal seal, or joint, 22 . Piece 21 is mounted on a spring 23 that bears against the lower face of disk 17 . The rest position of spring 23 corresponds to that shown in FIG. 3 in which valve 20 is closed.
Emptying receptacle 3 has a volume sufficient to receive the cooking bath contained in vessel 2 . Emptying receptacle 3 has a recovery trough 30 closed by a lid 31 , and has an outer lateral wall 32 . If desired, wall 32 can be made at least partially of a transparent or translucent material to permit the user to observe the filling of emptying receptacle 3 .
Receptacle 3 also has an emptying control mechanism 40 which can advantageously be mounted on recovery trough 30 . Control mechanism 40 includes a movable control piece 42 mounted around an inlet conduit 41 that opens into a lateral wall 33 of trough 30 . Movable control piece 42 is composed of a funnel 43 and a cam 44 provided to actuate spring-loaded valve 20 . Movable control piece 42 is connected to a maneuvering button 45 mounted on the outer lateral wall 32 of emptying receptacle 3 .
Maneuvering button 45 is mounted to be rotated in order to drive piece 42 in rotation. The lateral wall of conduit 41 has a filling opening 46 surrounded by a toroidal seal, or joint, 47 that provides a secure seal between conduit 41 and movable control piece 42 . Maneuvering button 45 is movable, for example in rotation, between a utilization position corresponding to the position shown in FIGS. 2 and 3 and an emptying position corresponding to the position shown in FIGS. 1 and 4. In the emptying position, shown most clearly in FIG. 4, funnel 43 is disposed above filling opening 46 , and cam 44 pushes valve 20 upwardly, against the force of spring 23 .
The appliance further includes a safety device 25 constructed to prevent withdrawal of emptying receptacle 3 when valve 20 is opened. For this purpose, the lower end of conduit 15 has a longitudinal slot 26 , and cam 44 , arranged as a part of funnel 43 , comes to be inserted into slot 26 during rotation of movable control piece 42 toward the emptying position, as shown in FIG. 4 . Control mechanism 40 thus includes bolt 27 provided to cooperate with a striking plate 28 , forming a part of valve 20 , when valve 20 is in its opened position. In the illustrated embodiment, bolt 27 is formed by a lateral face of cam 44 and striking plate 28 is formed by walls bounding slot 26 .
The appliance according to the invention includes a further safety device 50 that acts to prevent two consecutive emptyings without at least partial withdrawal of receptacle 3 from housing 1 .
For this purpose, device 50 includes a movable safety piece 51 disposed between housing 1 and emptying receptacle 3 . In the illustrated embodiment, piece 51 is mounted on the bottom wall of housing 1 . Piece 51 is guided by guide abutments 52 for movement in a longitudinal direction perpendicular to the plane of FIGS. 3 and 4. This longitudinal movement of piece 51 is limited by stops 53 located ahead of and behind, respectively, piece 51 . As shown in FIG. 5, a flexible blade 54 is mounted on piece 51 to come to abut against the bottom of emptying receptacle 3 during introduction of receptacle 3 into housing 1 , and to then bear against receptacle 3 when receptacle 3 has been fully introduced into housing 1 and piece 51 is blocked by one of the abutments 53 .
FIG. 6 shows emptying receptacle 3 after having been fully introduced into housing 1 . Piece 51 includes a first cam 55 provided to cooperate with a foot 48 extending downwardly from movable control piece 42 when maneuvering button 45 has been brought to its emptying position after receptacle 3 has been fully introduced into housing 1 . Piece 51 also includes a second cam 56 provided to cooperate with foot 48 when maneuvering button 45 is moved into its utilization position after an emptying operation. Piece 51 includes a blocking abutment 57 provided to prevent rotation of movable control piece 42 when maneuvering button 45 is urged toward the emptying position after a new utilization without prior withdrawal of emptying receptacle 3 .
The appliance is used in the following matter.
When the user fully introduces emptying receptacle 3 into housing 1 , cam 44 cannot reach movable blocking piece 21 of valve 20 , which is protected by the lower end of conduit 15 . Emptying receptacle 3 comes in contact with flexible blade 54 , as shown in FIG. 5, and pushes movable safety piece 51 toward a position that is remote from the lateral opening of housing 1 . When piece 51 comes to abut against the associated stop 53 (the right-hand stop in FIGS. 5 and 6 ), flexible blade 54 is depressed and comes to rub against the bottom of emptying receptacle 3 . Flexible blade 54 permits piece 51 to be maintained in place with respect to receptacle 3 .
When emptying receptacle 3 has been fully installed in housing 1 , as shown in FIG. 6, the user can rotate maneuvering button 45 toward the emptying position shown in FIGS. 1 and 4. During rotation of control piece 42 , foot 48 engages cam 55 to displace safety piece 51 toward an intermediate position, i.e., toward the left in FIG. 6 . At the end of the rotation travel of piece 42 , cam 44 lifts blocking piece 21 of valve 20 , as shown in FIG. 4 . Then, liquid contained in vessel 2 can flow through funnel 43 and filling opening 46 of conduit 41 and into receptacle 3 if thermostatic valve 16 is opened. Cam 44 , blocked by slot 26 , prevents withdrawal of emptying receptacle 3 .
In order to withdraw emptying receptacle 3 from housing 1 , the user returns maneuvering button 45 to the utilization position, shown in FIG. 3 . During the accompanying rotation of control piece 42 , foot 48 pushes cam 56 so as to displace safety piece 51 into the forward position shown in FIG. 2 . Cam 44 then moves clear of emptying device 10 and valve 20 recloses. Foot 48 moves clear of safety piece 51 and the user can then withdraw emptying receptacle 3 from housing 1 .
Due to the functioning of safety piece 51 , a new emptying is prevented if emptying receptacle 3 has not been withdrawn from housing 1 and then put back in place. In effect, during rotation of control piece 42 , foot 48 is blocked by abutment 57 and cam 44 cannot reach valve 20 . In order to allow a new emptying, it is necessary to withdraw receptacle 3 at least until it has moved away from flexible blade 54 , as shown in FIG. 5, in order to push piece 51 back with the aid of flexible blade 54 during reintroduction of receptacle 3 . A slight withdrawal of receptacle 3 will not guarantee that a reintroduction of receptacle 3 will result in a pushing back of piece 51 with the aide of flexible blade 54 .
Safety device 50 prevents a second emptying from being performed if receptacle 3 has not been withdrawn at least partially by a certain amount from housing 1 and then put back in place, through the intermediary of displacements of piece 51 during maneuvering of control device 40 from the utilization position toward the emptying position and back, as well as during withdrawal and then reintroduction of emptying receptacle 3 .
The capacity of emptying receptacle 3 can thus be limited to the capacity of vessel 2 , without risking an overflow of receptacle 3 as a result of two consecutive emptyings of vessel 2 .
According to one alternative, emptying control mechanism 40 need not be secured to recovery trough 30 , and can for example be mounted on lid 31 of emptying receptacle 3 .
According to another alternative, control piece 42 is not necessarily mounted between maneuvering button 45 and emptying receptacle 3 .
According to another alternative, maneuvering button 45 can be mounted on a lateral face of the emptying receptacle housed within the housing when the receptacle is installed in the housing. The maneuvering button can then be accessible through a hatch, or door, provided in the lateral wall of the housing.
According to another alternative, maneuvering button 45 can be mounted on housing 1 of the appliance, for example opposite the lateral window of the housing provided for insertion of the emptying receptacle. The connection between the maneuvering button and the control mechanism then takes place upon insertion of the emptying receptacle into the housing.
According to yet another alternative, flexible blade 54 can be mounted on one of the outside faces of the emptying receptacle or even on another internal face of the housing.
According to still another alternative, emptying receptacle 3 can form a base receiving, in a removable manner, the housing surrounding the vessel.
This application relates to subject matter disclosed in French Application Number FR 01 13395, filed on Oct. 17, 2001, the disclosure of which is incorporated herein by reference.
The foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without undue experimentation and without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. The means, materials, and steps for carrying out various disclosed functions may take a variety of alternative forms without departing from the invention.
Thus the expressions “means to . . . ” and “means for . . . ”, or any method step language, as may be found in the specification above and/or in the claims below, followed by a functional statement, are intended to define and cover whatever structural, physical, chemical or electrical element or structure, or whatever method step, which may now or in the future exist which carries out the recited function, whether or not precisely equivalent to the embodiment or embodiments disclosed in the specification above, i.e., other means or steps for carrying out the same functions can be used; and it is intended that such expressions be given their broadest interpretation.
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A cooking appliance composed of: a housing; a vessel provided to be placed in the housing and arranged to receive a cooking bath; an emptying device provided in the vessel for permitting the cooking bath to be drained from the vessel; an emptying receptacle for receiving the cooking bath from the vessel; a first valve associated with the emptying device; a maneuvering button associated with the emptying device; and a control mechanism mounted on the emptying receptacle and interposed between the maneuvering button and the first valve for moving the first valve between open and closed positions and response to movements of the maneuvering button, wherein the emptying receptacle is removable from the housing.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an air-conditioning system which performs air-conditioning, such as air-cooling, heating and dehumidification, and which is provided with an air cleaner capable of eliminating the dust and odorants from the air.
2. Description of the Related Art
An air-conditioning system performs air conditioning (such as air-cooling, heating and dehumidification) by drawing the air of a room into the heat exchanger of its indoor unit and performing heat exchange with respect to the drawn air.
An air-conditioning system recently developed is provided with an air cleaner which removes fine dust particles and odorants from the air circulated by the air-conditioning system. In this type of air-conditioning system, the air cleaner is made up of an electric dust-collecting device and an odorant filter device, and is arranged in front of the heat exchanger. The electric dust-collecting device includes a plurality of ionization wires connected to the positive terminal of a high d.c. voltage source. It also includes an electrode body having a plurality of electrode plates facing the ionization wires. The odorant filter device contains an activated carbon filter.
In general, it is desirable that the indoor unit of an air-conditioning system be installed on a wall portion close to the ceiling since the indoor unit installed at such a wall portion allows the floor space to be used effectively. It is also desirable that the indoor unit be as flat as possible since such a flat indoor unit does not give a feeling of oppression to the user.
Since the indoor unit installed on a wall portion close to the ceiling is limited in its vertical dimension, the heat exchanger incorporated in the indoor unit is also limited in its vertical dimension. Therefore, the heat exchanger is elongated in the widthwise direction of the indoor unit, so as to ensure a sufficiently wide heat exchange area. Accordingly, both the heat exchanger and the main body of the indoor unit are short in the vertical direction and are long in the horizontal direction.
If the air cleaner arranged in front of the heat exchanger has the same shape as the heat exchanger, it causes air resistance with reference to the heat exchanger. Because of this air resistance, the pressure loss of the air flowing into the heat exchanger increases, resulting in deterioration in the heat exchange efficiency of the air-conditioning system.
To solve this problem, the shape of the conventional air cleaner is determined in such a manner that its horizontal dimension is equal to that of the heat exchanger but its vertical dimension is half that of the heat exchanger. That is, the air cleaner is very long in the horizontal direction. If an air cleaner has such a shape, it does not cause much air resistance with reference to the heat exchanger. Thus, necessary heat exchange efficiency is ensured for the heat exchanger, and sufficient air cleaning efficiency is ensured for the air cleaner. The heat exchanger is fixed inside the main body of the indoor unit and has plates at the ends thereof. Both ends of the air cleaner are attached to the respective plates of the heat exchanger.
Although the air cleaner is very long, it is fixed only at the longitudinal ends. In other words, no support means is provided at an intermediate point of the air cleaner.
An air-conditioning system is transported after it is manufactured in a factory. During the transportation, vibration is applied to the air-conditioning system not only in the vertical direction thereof but also in the horizontal and diagonal directions. Since the air cleaner is fixed only at ends, as mentioned above, it bends during the transportation. In particular, its central portion greatly bends during the transportation. Due to this bending, the air cleaner may be damaged during the transportation. In the worst case, the air cleaner may be broken, or the portion for supporting the ionization wires of the electric dust-collection device may be deformed, resulting in disconnection of the ionization wires.
One measure for preventing this problem is to employ thick (therefore rigid) ionization wires. However, if thick ionization wires are used, the manufacturing cost of the air-conditioning system is increased, and the total weight of the air-conditioning system is also increased.
Another measure for preventing the problem is disclosed in Published Unexamined Japanese Patent Application No. 1-210045. According to this reference, a unit frame is provided with batten ribs, and these batten ribs are in contact with the heat exchanger. Due to the provision of the batten ribs, the distance between the unit frame and the heat exchanger is always maintained at a constant value. The distance remains unchanged even if the unit frame is pressed against the heat exchanger by an external force.
However, the vibration during the transportation does not always act in such a direction that the air cleaner is pressed against the heat exchanger. The heat cleaner is not only vibrated back and forth but also vibrated in the vertical and diagonal directions. The batten ribs may prevent the unit frame from touching the heat exchanger, but cannot suppress the vibration occurring in the other directions. Therefore, it is possible that the air cleaner will be deformed as a result of the vibration.
SUMMARY OF THE INVENTION
The present invention has been developed in consideration of the above problems of the prior art, and an object of the invention is to provide an air-conditioning system which is of a type incorporating an air cleaner, which prevents the air cleaner from swinging and maintains the distance between the air cleaner and the heat exchanger at a constant value even if vibration acts in any direction during transportation, and which therefore prevents the air cleaner from being damaged or deformed during the transportation.
To achieve this object, the present invention provides an air-conditioning system which comprises:
an indoor unit which is to be arranged in a room to be air-conditioned, and which includes a heat exchanger, and circulating means for causing the air in the room to be circulated through the heat exchanger;
an air cleaner, incorporated in the indoor unit, for eliminating dust and odorants from the air, the air cleaner being arranged in front of the heat exchanger, with a predetermined gap provided with reference to the heat exchanger; and
engaging means, projected from the air cleaner and engaging with the heat exchanger, for preventing the air cleaner from vibrating and for maintaining the predetermined gap between the heat exchanger and the air cleaner.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate a presently preferred embodiment of the invention, and together with the general description given above and the detailed description of the preferred embodiment given below, serve to explain the principles of the invention.
FIGS. 1 through 5 illustrate an air-conditioning system, incorporating an air cleaner, according to one embodiment of the present invention, of which:
FIG. 1 is a front view of an indoor unit of the air-conditioning system;
FIG. 2 is a front view of the indoor unit whose front panel is open;
FIG. 3 is a cross sectional view of the indoor unit;
FIG. 4 is a front view which shows indoor door unit but omits illustration of the casing thereof; and
FIG. 5 is a cross sectional view in which the heat exchanger and the air cleaner are partly depicted in an enlarged scale.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
One embodiment of the present invention will now be described, with reference to the accompanying drawings.
FIG. 1 is a front view of the indoor unit of an air-conditioning system (which is of a type incorporating an air cleaner) according to one embodiment of the present invention, and FIGS. 2 and 3 individually show the internal structure of the indoor unit.
The indoor unit comprises a rectangular box-like casing 1, and is installed on a wall R of a room to be air conditioned. A heat exchanger 3, an air-sending fan 4, and an air cleaner S, and other structural components are arranged inside the casing 1. The casing 1 is provided with a front panel 2. This front panel 2 can be opened or closed with reference to the casing 1, with the uppermost portion as a center. When the front panel 2 is open (or when it is moved up to the position indicated by the two-dot-dash lines in FIG. 3), the interior of the casing 1 is exposed, as is shown in FIG. 2.
As is best understood in FIG. 3, the heat exchanger 3 inside the casing 1 is slanted with reference to a vertical plane such that the upper edge is closer to the rear wall of the casing 1 than the lower edge.
The air-sending fan 4 is located under the rear wall of the heat exchanger 3. When this fan 4 is driven, the air in the room is circulated in the manner indicated by the arrows in FIG. 3. More specifically, the air is drawn into the casing through air inlet ports 5 formed in the front panel 2, and passes through the heat exchanger 3, for heat exchange. Thereafter, the air is blown into the room through air outlet ports 6 located below the front panel 2.
The casing 1 is formed to be as flat as possible, and is more elongated in the horizontal direction than in the vertical direction. Likewise, the heat exchanger 3 fixed inside the casing 1 is formed to be as flat as possible, and is more elongated in the horizontal direction than in the vertical direction.
The air cleaner S is located in front of the heat exchanger 3 (i.e., in the air inlet region). It is made up of an electric dust-collecting device 7, an odorant filter device 8, and a controller 9.
The casing 1 is provided with a main frame 10 having a left-side frame portion 10a and a right-side frame portion 10b. Normally, the electric dust-collecting device 7 is arranged in the left-side frame portion 10a, and the odorant filter device 8 is arranged in the right-side frame portion 10b. However, they may be arranged in the opposite manner, if so desired.
The electric dust-collecting device 7 and the odorant filter device 8 are slanted in parallel to the heat exchanger 3, with their upper edges being substantially at the same level as the upper edge of the heat exchanger 3. They are spaced away from the heat exchanger 3 by a predetermined distance.
The electric dust-collecting device 7 and odorant filter device 8 have vertical dimensions which are about half that of the heat exchanger 3. Instead, they are elongated in the horizontal direction.
As can be understood from FIG. 2, which shows the state where the front panel 2 is open, the upper half of the heat exchanger 3 is covered with the electric dust-collecting device 7 and odorant filter device 8, whereas the lower half thereof is uncovered.
The controller 9 controls not only the electric dust-collecting device 7 but also the entire operation of the air-conditioning system.
A filter guide 11 is located in front of the air cleaner S. Being guided by this filter guide 11, an air filter 12 is inserted into the region behind the air inlet ports 5 of the front panel 2 or is removed from that region.
As is shown in FIG. 5, the heat exchanger 3 comprises a heat-exchanging pipe 13 and a large number of fins 14. The heat-exchanging pipe 13 is bent and arranged in such a manner as to have a front-row section and a rear-row section. In each section, the adjacent portions of the heat-exchanging pipe 13 are spaced from each other by a predetermined distance. The pipe portions of the front-row section do not oppose the corresponding pipe portions of the rear-row section; they are shifted from the corresponding ones in the vertical direction. The fins 14 are very thin and are arranged in the axial direction of the heat-exchanging pipe 13 at very short intervals.
The electric dust-collecting device 7 is made up of an ionization section 20 and a dust collection section 21.
In the ionization section 20, one ionization wire 15 is arranged in a zigzag pattern. Both ends of this ionization wire 15 are electrically insulated. A frame 17 having slits 16 is arranged such that the slits 16 correspond in location to the regions between the adjacent turns of the ionization wire 15. A facing plate 18, which is grounded, is removably attached to the frame 17. The facing plate 18 is formed by a metal plate, such as a stainless steel plate, and is partly cut and raised such that the raised portions constitute electrode plates 19 inserted into the slits 16 of the frame 17. Each turn of the ionization wire 15 passes through the region defined between the electrode plates 19.
The dust collection section 21 is located on the rear side of the ionization section 20. The dust collection section 21 includes a rectangular frame body 22, and a large number of belt-like synthetic resin sheets 23 which are stacked upon each other at a predetermined pitch and held in the frame body 22. A conductive layer (e.g., a coating of conductive paint) is formed on one side of each synthetic resin sheet 23, and is electrically connected to an electrode (not shown). The frame body 22 is pressed against, and is supported by a collector support 24 arranged in the left-side frame portion 10a of the main frame 10. The frame body 22 has a handle 25 integrally extending from the lower portion thereof. This handle 25 is projected downward from the lower face of the main frame 10. The dust collection section 21 can be easily removed from the electric dust-collecting device 7 by pulling it down with the handle 25, and can be easily inserted into the predetermined region inside the electric dust-collecting device 7 by raising it with the handle 25.
As is shown in FIGS. 2 and 4, the odorant filter device 8 is located between the electric dust-collecting device 7 and the controller 9. The odorant filter device 8 comprises a handle 26 which is integral with the lower portion of the device 8, and a case 27 which is removably by set in the right-side frame portion 10b of the main frame 10. The case 27 contains an odorant-removing filter 28, e.g., an activated carbon filter.
A pair of engaging pieces 30 are projected from the horizontal center of the rear face of the air cleaner S mentioned above. In other words, the position of the engaging pieces 30 corresponds to that of a main frame's central portion 10c (FIG. 2), on both sides of which the electric dust-collecting device 7 and the odorant filter device 8 are arranged.
As is shown in FIG. 5, the engaging pieces 30 are spaced apart in the vertical direction and aligned with each other. The thickness of each engaging piece 30 is smaller than the interval between the fins 14 of the heat exchanger 3. The vertical dimension of each engaging piece 30 is decreased from the proximal portion to the distal end portion thereof, and has a substantially triangular shape.
The engaging pieces 30 each have a semi-circular cutaway section 31 whose radius is substantially equal to that of the heat-exchanging pipe 13 of the heat exchanger 3. The cutaway section 31 of the upper engaging piece 30 is formed on the lower portion thereof, while the cutaway section 31 of the lower engaging piece 30 is formed on the upper portion thereof. In short, the cutaway section 31 of one engaging piece 30 faces that of the other. The distance between the engaging pieces 31 is substantially equal to the distance between the predetermined turns of the heat-exchanging pipe 13. Each engaging piece 30 is projected from the rear face of the air cleaner S, and the distal end thereof is inserted between the adjacent fins 14 of the heat exchanger 3.
The cutaway section 31 of each engaging piece 30 is fitted around one turn of the heat-exchanging pipe 13. In this state, the paired engaging pieces 30 engage with the heat-exchanging pipe 30 and clasps the predetermined turns of the pipe 30 from above and from below.
In the manner mentioned above, the air cleaner S is fixed to the heat exchanger 3 by means of the engaging pieces 30. With this structure, the air cleaner S is prevented from swinging not only in the vertical direction but also in the other directions. In addition, the gap between the rear face of the air cleaner S and the front face of the heat exchanger 3 is maintained at a constant value by the engaging pieces 30.
A description will now be given of the operation of the above-mentioned air-conditioning system.
Part of the air in a room is introduced into the air-conditioning system through the air inlet ports 5. The introduced air passes through the air filter 12, by which comparatively large dust particles are removed from the air.
Part of the introduced air passes through either the electric dust-collecting device 7 or the odorant filter device 8 before it reaches the heat exchanger 3. When passing through the electric dust-collecting device 7, fine dust particles included in the air are ionized because of the electric discharge caused by the ionization wire 15, and are therefore caught by the dust collection section 21. When passing through the odorant filter device 8, the air is cleared of odorants. Accordingly, the air is cleaned by the electric dust-collecting device 7 and the odorant filter device 8.
Next, the air passes through the heat exchanger 3, where heat exchange is performed with respect to the air. After this heat exchange, the air is blown into the room through the air outlet ports 6 of the casing 1.
Like the conventional air-conditioning system, the air-conditioning system of the above embodiment is subjected to vibration when it is transported. Since the air cleaner S of the air-conditioning system is elongated in the horizontal direction, as in the conventional system, its central portion is subjected to the vibration intensively. However, the central portion of the air cleaner S is fixed to the heat-exchanging pipe 13 by means of the engaging pieces 30. With this structure, the air cleaner S is prevented from swinging in the vertical, horizontal, and diagonal directions.
Since the air cleaner S is reliably prevented from swinging, it is not deformed during transportation. In addition, the ionization wire 15 of the electric dust-collecting device 7 is prevented from breaking since it is not exerted with an excessive force. Thus, the function of the air cleaner S is not adversely affected during transportation.
Moreover, the engaging pieces 30 maintains a predetermined gap between the air cleaner S and the heat exchanger 3. The heat exchanger generates water as a result of the heat exchange operation, but such water is drained through the gap and does not enter the air cleaner S. Therefore, the dust-collecting efficiency and the insulated state of the air cleaner are in no way adversely affected by the water generated by the heat exchanger.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, and representative devices, shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
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An indoor unit of an air-conditioning system is provided with a heat exchanger, a fan, and an air cleaner. The fan introduces the air in a room into the indoor unit, and blows the air back into the room after guiding the air to pass through both the heat exchanger and the air cleaner. The heat exchanger performs heat exchange with reference to the air circulated by the fan, for air-cooling, heating, or dehumidification. The air cleaner is arranged in front of the heat exchanger, with a predetermined gap maintained with reference to the heat exchanger. The air cleaner catches dust particles in the air and eliminates odorants from the air. The air cleaner is provided with engaging members. These engaging members are projected from the air cleaner and engage with the heat exchanger. Accordingly, the air cleaner is prevented from swinging, and the gap between the air cleaner and the heat exchanger is maintained at a constant value.
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CROSS-REFERENCE
[0001] This application claims priority to German patent application no. 10 2015 202 720.1 filed on Feb. 16, 2015, the contents of which are fully incorporated herein by reference.
TECHNOLOGICAL FIELD
[0002] The present disclosure is directed to a bearing assembly including a hub element or housing element with at least one opening for a bearing and at least one bearing element secured in the at least one opening by a press fit.
BACKGROUND
[0003] Known bearing assemblies may include a housing element or a hub element that has at least one opening for receiving first and second bearing rings such that the second bearing ring is movable relative to the first bearing ring. These may be used, for example, as wheel hub bearing assemblies in motor vehicles. In such assemblies, the bearing outer ring is usually press fit in the at least one opening on the hub element. The bearing rings must be strong enough to withstand the forces to which they are subjected and are therefore generally made mostly of steel, in particular of rolling-element bearing steel (e.g., 100Cr6). In order to reduce weight, a lighter material, such as aluminum, is often used to form the hub element or housing element.
[0004] The light weight of aluminum wheel hubs makes them desirable for wheel-bearing arrangements. A disadvantage of aluminum wheel hubs, however, is that aluminum has a substantially greater coefficient of thermal expansion as compared to that of steel. This means that it is difficult to design the connection or interface between steel parts and aluminum parts for all relevant temperature ranges. The different degrees of expansion may prove particularly troublesome at the press-fit junction between the hub element and the bearing outer ring. At high temperatures the fit between these elements can loosen, since the aluminum hub will expand more than the steel bearing ring. This may allow the bearing outer ring to shift or rotate in the hub, and such movement can damage the hub and/or the bearing.
[0005] On the other hand, at low temperatures the aluminum hub strongly constricts the outer ring and may cause high contact stresses. This may cause the hub to crack or may deform the bearing ring, in particular on the raceway.
[0006] It was therefore proposed in DE 10 2012 211 261 (family member of U.S. Pat. No. 8,961,028) to provide a specific design for a bearing assembly with a hub element or housing element and a rolling-element bearing outer ring press-fit in a receiving bore. In order to ensure a proper fit of the bearing ring at all operating temperatures, even with the use of different materials for the hub element or housing element and the bearing ring, the designs of the receiving bore and of the outer circumference of the outer ring are configured in a particular manner. Specifically, they are configured such that the radial press-fit between receiving bore and the outer ring is smaller in the region of the raceway than in the region outside the raceway. This can be achieved, for example, by the varying the diameter of the receiving bore or of the outer ring over its axial length.
[0007] However, a disadvantage of this conventional approach is that forming the axial extensions of the receiving bore or outer ring with varying diameters is very expensive, and in addition each element must be individually manufactured. Such bearing assemblies are thus very cost-intensive.
SUMMARY
[0008] One aspect of the present disclosure is therefore to provide a bearing assembly, in particular for a wheel hub bearing, that is simple to manufacture and that allows for improved mounting of the bearing ring in a housing element or hub element even when the housing element/hub element and bearing ring are formed from materials with different properties.
[0009] The present disclosure relates to a bearing assembly including a housing element or hub element that includes at least one opening for a bearing including a first bearing element and a second bearing element movable relative to a first bearing element. The first bearing element is press-fit in the opening. In order to ensure a proper fit of the bearing element in the housing element or hub element even when the housing element or hub element and the bearing element are made of different materials and over a range of operating temperatures, an intermediate element is disposed in the opening, and the first bearing element is received in the intermediate element with press-fit. The intermediate element allows a different press-fit between the intermediate element and the opening and between the bearing ring and the intermediate element. In this manner, the bearing elements can be mounted on or in the opening on the housing element or hub element under the optimal conditions for them. In order to further improve the connection between intermediate element and opening, the intermediate element may include at least one projection that can enter into operative connection with the opening. The projection is preferably wave-shaped and/or lug-shaped. The friction of the intermediate element in the opening can thereby be increased such that radial and axial movement of the intermediate element in the opening is made more difficult or prevented.
[0010] According to a further exemplary embodiment it is preferred that the projection engage into a recess formed in the opening. Radial and axial movement of the intermediate element in the opening is thereby further made more difficult or prevented.
[0011] According to one further advantageous exemplary embodiment, the housing element or hub element is formed from a first material, in particular aluminum, having a first coefficient of thermal expansion, and the intermediate element is made from a second material, in particular steel, having a second coefficient of thermal expansion different from that of the first coefficient of thermal expansion. A bearing assembly can thereby be provided in which light metal is preferably used for the hub element or housing element, while at the same time rolling-element bearing steel, which is preferred for its superior strength, can be used for the bearing rings. As a result a bearing assembly can be manufactured that is both lightweight and that satisfies the stipulated strength requirements. The intermediate elements between the bearing ring and the hub or housing element help ensure that the different materials of these elements do not directly affect one another.
[0012] According to a further advantageous exemplary embodiment, the intermediate element and the bearing element received therein are formed from materials having similar or identical coefficients of thermal expansion or are formed from the same material. This helps ensure that the press-fit between the intermediate element and the bearing element remains essentially constant over a large range of operating temperatures, such as occurs in particular in wheel hub bearing assemblies. This in turn makes it possible that even at high temperatures the bearing element does not loosen from the intermediate element or that the intermediate element is not deformed at very low temperatures.
[0013] The intermediate element itself can be press-fit in the housing element or hub element, or it can be directly cast into the material of the housing element or hub element. Of course it is also possible with a plurality of intermediate elements disposed on the bearing housing to attach the intermediate elements to the housing element or the hub element using different attachment methods. However, press fitting the intermediate element in the opening of the housing element or hub element is particularly advantageous. For example, the intermediate element can be received in the opening with a very tight press-fit, so that even at very high temperatures the intermediate element does not loosen significantly. Such a tight press-fit would not be possible for the bearing element itself, since it could deform the precisely prepared raceway or sliding surface of the bearing ring.
[0014] The bearing assembly may be a component of a wheel hub bearing assembly and include a first opening and a second opening axially spaced from each other, and first and second rolling element bearings press-fit into the openings. The rolling-element bearings preferably each include an outer ring and an inner ring, and at least one of the outer rings is press-fit in the intermediate element, the intermediate element being disposed in at least one of the openings formed on the hub element. Using the intermediate element of the present disclosure, thermal influences on the hub element and on the outer ring can be decoupled from each other in a simple and cost-effective manner.
[0015] Further advantages and advantageous embodiments are defined in the description, the drawings, and the claims.
[0016] In the following aspects of the disclosure are described in more detail with reference to the exemplary embodiments depicted in the Figures. Here the exemplary embodiments illustrated are of a purely exemplary nature and are not intended to establish the scope of the application. This scope is defined solely by the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a schematic, sectional, side elevational view of a first exemplary embodiment of a bearing assembly according to the disclosure.
[0018] FIG. 2 is a schematic, sectional, side elevational view of a second exemplary embodiment of a bearing assembly according to the disclosure.
DETAILED DESCRIPTION
[0019] In the following, identical or functionally equivalent elements are designated by the same reference numbers.
[0020] In FIG. 1 a wheel bearing 1 is depicted in radial cross-section as a preferred exemplary embodiment of the disclosure. Only the components relevant to the description of the exemplary embodiment are depicted and described. The wheel bearing 1 comprises a hub element 2 for attaching a rim to a wheel bearing 1 . First and second openings 4 , 6 are formed in the hub element 2 , and these first and second openings 4 , 6 are configured to receive first and second rolling-element bearings 8 , 10 , respectively. The rolling-element bearings 8 , 10 rotatably support the wheel bearing 1 on a wheel axis (not shown), and each includes an outer ring 12 , 14 , rolling elements 16 , 18 , cages, 20 , 22 , and an inner ring 24 , 26 . The inner rings 24 , 26 have different bore diameters, and the smaller inner ring 24 is disposed behind the larger inner ring 26 with respect to the insertion direction of the wheel axis.
[0021] The rolling-element bearings 8 and 10 are axially spaced from each other, and a connecting piece 28 is disposed between the rolling element bearings 8 , 10 that is in contact with the inner rings 24 , 26 of the rolling element bearings and that fixes the axial spacing of the rolling-element bearings 8 , 10 with respect to each other. The connecting piece 28 is preferably sleeve-shaped so that the wheel axis can pass therethrough. The bore diameter of the connecting piece 28 is chosen such that at radially circulating contact points 30 , 32 with the inner rings 24 , 26 it has essentially the same respective bore diameter as the adjacent inner ring 24 , 26 . It can optionally be respectively embodied smaller or larger.
[0022] Furthermore, FIG. 1 shows intermediate elements 34 , 36 disposed between the outer rings 12 , 14 and the openings 4 , 6 . The outer rings 12 , 14 are in turn press-fit in these intermediate elements 34 , 36 . The intermediate elements 34 , 36 serve to compensate for the influence of the different coefficients of thermal expansion of the hub element 2 and the outer rings 12 , 14 , and the intermediate elements 24 , 26 may comprise rings or be ring-shaped.
[0023] This arrangement is particularly advantageous if the hub element 2 and the outer rings 12 , 14 are comprised of different materials. Thus, for example, it is preferable to manufacture the hub element 2 from a light metal, such as aluminum, in order to reduce the total weight of the wheel hub. However, aluminum is itself not a suitable material for forming the outer bearing rings 12 , 14 , because of the high strength required for bearing rings. The bearing rings 12 , 14 ; 24 , 16 are therefore usually manufactured from rolling-element bearing steel (e.g., 100Cr6). Disadvantageously, however, the coefficients of thermal expansion of aluminum and of the rolling-element bearing steel differ significantly; aluminum expands approximately twice as much as steel does per degree of temperature change. Since the wheel bearings may be operated over a temperature range of −40° to 180° C., this difference in coefficients of thermal expansion is not negligible. This in turn makes it very difficult to design the connection or interface between the steel parts and the aluminum parts for all relevant temperature ranges. Thus at high temperatures the fit of the bearing rings 12 , 14 mounted directly in the openings 4 , 6 can loosen, while at low temperatures the aluminum of the hub element can contract so much that very high contact stresses arise. However, in the present disclosure, this problem is addressed by providing the intermediate elements 34 , 36 in the openings 4 , 6 in order to compensate for these differences. The intermediate elements 34 , 36 are preferably manufactured from steel. Alternatively the intermediate elements 34 , 36 can also be manufactured from a material that has a coefficient of thermal expansion similar to that of the of the material from which the outer rings 12 , 14 are manufactured. The force of the press-fit between the outer rings 12 , 14 and the intermediate elements 34 , 36 thereby remains substantially constant over the entire operating temperature range so that damage to the bearing due to overtensioning or loosening of the bearing is prevented.
[0024] The intermediate elements 34 , 36 in turn can be press-fit in the openings 4 , 6 of the hub element 2 . The press-fit between the intermediate elements 34 , 36 and the openings 4 , 6 can also be very tight because temperature-related contractions of the hub element 2 will not substantially affect the bearing outer rings 12 , 14 . As used herein “very tight” refers to a press-fit that is too tight for mounting a bearing outer ring directly in a hole in a hub or housing.
[0025] As shown in the enlarged detail in FIG. 1 , the intermediate elements 34 , 36 can include a ribbing 40 on their edges 38 facing the hub element 2 , which ribbing 40 enters into operative connection with the opening 4 , 6 and tightens the press-fit of the intermediate element 34 , 36 in the opening 4 , 6 . Here the ribbing 40 can grab into the material of the hub element such that the friction between the intermediate elements 34 , 36 and the openings 4 , 6 is increased. In this manner, even at high operating temperatures, the intermediate elements 34 , 36 are disposed in the openings 4 , 6 such that they are captive and do not rotate.
[0026] As an alternative, FIG. 2 shows the intermediate elements 34 , 36 can also be cast into the hub element 2 during the manufacturing process. As the detail in FIG. 2 illustrates, lug-shaped projections can be formed on the radially outer edge of the intermediate elements 34 , 36 , which lug-shaped projections engage into complementarily designed indentations 44 , 46 in the openings 4 , 6 . Even with large temperature fluctuations the intermediate elements 34 , 36 can be radially and axially secured in the openings 4 , 6 .
[0027] In addition, elements (not depicted) can also be disposed on the outer edge 48 of the hub element 2 , which elements prevent a thermal expansion of the hub element 2 . These elements can also be introduced into the hub element 2 with press-fit or by casting-in.
[0028] Overall, using the disclosed intermediate elements 34 , 36 a bearing assembly can be provided that is very simple to manufacture and that provides a uniform preload in the bearing. In addition, the bearing outer ring cannot loosen from its seat, which may significantly increase the service life of the bearing.
[0029] Representative, non-limiting examples of the present invention were described above in detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the invention. Furthermore, each of the additional features and teachings disclosed above may be utilized separately or in conjunction with other features and teachings to provide improved bearing assemblies.
[0030] Moreover, combinations of features and steps disclosed in the above detailed description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe representative examples of the invention. Furthermore, various features of the above-described representative examples, as well as the various independent and dependent claims below, may be combined in ways that are not specifically and explicitly enumerated in order to provide additional useful embodiments of the present teachings.
[0031] All features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter, independent of the compositions of the features in the embodiments and/or the claims. In addition, all value ranges or indications of groups of entities are intended to disclose every possible intermediate value or intermediate entity for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter.
REFERENCE NUMBER LIST
[0032] 1 Wheel bearing
[0033] 2 Hub element
[0034] 4 , 6 Opening
[0035] 8 , 10 Rolling-element bearing
[0036] 12 , 14 Outer ring
[0037] 16 , 18 Rolling elements
[0038] 20 , 22 Rolling-element bearing cage
[0039] 24 , 26 Inner ring
[0040] 28 Connecting sleeve
[0041] 30 , 32 Connecting points between connecting sleeve and inner rings
[0042] 34 , 36 Intermediate element
[0043] 38 Outer edge of the intermediate element
[0044] 40 Ribbing
[0045] 42 Lug-shaped projections
[0046] 44 , 46 Indentations in the openings
[0047] 48 Outer edge of the hub element
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A bearing assembly includes a hub element or a housing element, the hub element or the housing element having at least one opening, at least one intermediate element mounted in the at least one opening, the at least one intermediate element including at least one wave-shaped or lug-shaped projection in contact with the hub element or the housing element, and a first bearing element press-fit in the at least one intermediate element and a second bearing element mounted in the at least one opening, the second bearing element being movable relative to the first bearing element.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a strap wrench for turning an object of cylindrical overall shape in one direction. This type of wrench includes a part forming a handle, and a strap, particularly made of metal, in the form of a loop, the two opposite strand parts of which cooperate with two zones secured to the handle when the strap is wrapped tightly around the object.
The handle is equipped, between the two zones, with a shoe for pressing against the object. The pressing shoe is not connected to the strap and has a bearing face of cylindrical overall shape with its generatrices at right angles to the overall plane of the strap.
The invention applies particularly to oil filter wrenches for motor vehicles and, in what follows, reference will be made to this application.
2. Description of Related Art
Examples of such strap wrenches are described in FR-A-1,570,027 and in EP-A-0,618,045 in the name of the Applicant Company.
In these known strap wrenches, the shoe is secured rigidly to the handle. As a result, when the space available around the oil filter allows the wrench to be turned only by a limited amount, the operator has to perform repetitive manipulations of shortening/lengthening the useful length of the strap, using a knurled knob which forms part of a screw-nut mechanism for adjusting the strap.
SUMMARY OF THE INVENTION
The object of the invention is to make strap wrenches easier to use in a particularly ergonomical way.
To this end, the subject of the invention is a strap wrench of the aforementioned type, characterized in that the shoe is pivot-mounted with respect to the handle so that it can pivot about a geometric axis associated with the handle and at right angles to the overall plane of the strap. This axis is located in such a way that when the shoe and the strap are both clamped tightly against the object, action on the handle exerted in a first direction causes the object to be turned and, exerted in the other direction, causes the shoe and the strap to slip on the object.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will now be described with reference to the appended drawings, in which:
FIG. 1 depicts, in longitudinal section, a strap wrench according to the invention with the strap in position loosely around an oil filter that is to be unscrewed;
FIG. 2 is a similar view after the strap has been adjusted to fit tightly around the oil filter;
FIG. 3 is a similar view during the first phase of unscrewing the filter;
FIG. 4 is a similar view, during the subsequent phase of backing up the wrench;
FIG. 5 depicts, in longitudinal section, another embodiment of the strap wrench according to the invention, during the first phase in the unscrewing;
FIG. 6 is a partial view from an exploded perspective of another embodiment of the strap wrench according to the invention;
FIG. 7 is a face-on view from the outside of the strap wrench of FIG. 5;
FIG. 8 is a side-on view from the outside of the same tool;
FIGS. 9 and 10 are views from the outside of an alternative form of the strap wrench of FIG. 5, the strap not being depicted;
FIG. 11 is a view in longitudinal section, taken in the overall plane of the strap, of an alternative form;
FIG. 12 depicts an alternative form of the shoe; and
FIG. 13 is an enlarged view of detail XIII of FIG. 12 .
DETAILED DESCRIPTION OF THE INVENTION
The strap wrench 1 depicted in FIGS. 1 to 4 is intended mainly for unscrewing and, in addition, by turning the wrench over, for screwing on, objects 2 of cylindrical overall shape, especially oil filters, the diameters of which may vary across a broad range, for example, in the embodiment depicted, from 66 to 96 mm.
To describe the wrench 1 more conveniently, it will be assumed to be oriented as illustrated in the drawings, with the filter 2 with its axis O horizontal and situated above the wrench.
The strap wrench 1 comprises the following:
1) A rigid body 3 which comprises a base 4 from which there extends a yoke 5 , the legs of which are parallel to the plane of the drawing.
2) A threaded rod 6 which may be a multiple-start thread, the lower end of which bears a knurled operating knob 7 while its plain and smaller-diameter, upper end 8 rotates in a central hole 9 in the base 4 , while being prevented from translational movement in this hole. An example of such an arrangement is described in the aforementioned FR-A-1,570,027.
3) A nut 10 mounted on the rod 6 .
4) A band, especially made of metal, 11 , forming a strap, each end part of which passes with a copious amount of clearance through a lateral slot 12 in the base 4 and then, below this slot, is fixed to the nut 10 by means of a screw 13 . The strap is guided laterally in each slot 12 which, opposite the other slot 12 , has a surface 14 on which the strap can bear. The surfaces 14 diverge in the direction of the object 2 and may be domed. As an alternative, these bearing surfaces could be defined by the peripheral surface of two rollers, as described in the aforementioned French A-publication.
5) A shoe 15 , for pressing on the filter 2 , is articulated in the yoke 5 about a pin 16 the axis of which bears the same reference numeral. The pin 16 protrudes from the shoe on each side and rotates in two holes formed in the legs of the yoke 5 . The shoe is placed freely between the two strand parts of the strap 11 .
6) A hairpin spring 17 wound around the pin 16 . One end of this spring bears against the upper face of the base 4 and its other end bears under a second pin 18 secured to the shoe 15 . The pin 18 protrudes from the shoe on each side thereof, and its ends are housed in arcshaped slots 19 formed made in the legs of the yoke 5 . The arc-shaped slots are formed such that the axis of pin 16 is the center.
The upper face 20 of the shoe has a cylindrical overall shape with generatrices at right angles to the mean plane of the strap 11 , which is the plane of the drawing. The directrix of the cylinder may be circular, for example of a radius that corresponds to the smallest radius of the filters that are to be manipulated, as depicted, or as an alternative may be in the shape of a very open V. The face 20 is additionally shaped with sawteeth inclined to the right in the figures, in an attempt to gain a grip or purchase on the object 2 in a preferred direction, as will become evident later.
The assembly comprising the body 3 and rod 6 with its knob 7 is symmetric with respect to a plane P, which is parallel to the axis O or at right angles to the mid-plane of the strap, which passes through the axis X—X of the rod 6 . The axis 16 is offset to the right with respect to the plane P, and the axis of the pin 18 is offset to the left with respect to this plane.
Thus, at rest (FIG. 1 ), the spring makes the shoe 15 pivot about the axis 16 in the clockwise direction until the pin 18 comes into abutment against the upper end of the slots 19 .
The unscrewing of the filter 2 using the wrench 1 will now be described.
The strap is fitted loosely around the filter (FIG. 1) Next, the knob 7 is turned in the clockwise direction (FIG. 2 ). Because of the lateral guidance of the two strand parts of the strap in the slots 12 , this movement causes the nut 10 to descend along the threaded rod, and therefore shortens the useful length of the strap, that is to say its length emerging from the body 3 .
When the shoe is pressing against the filter, the strap begins to be tensioned, pressing against the zones 14 of the base 4 . Continuing to turn the knob 7 forces the body 3 /rod 6 assembly to pivot slightly in the clockwise direction (arrow F 1 in FIG. 2) about the axis 16 , compressing the spring 17 . The pin 18 therefore leaves the upper end of the slots 19 .
The operator feels a markedly increased resistance to the turning of the knob 7 as soon as this compression of the spring 17 begins. He can therefore stop operating the knob 7 , and the wrench will be in the position of FIG. 2 ready to turn the filter 2 . If he nonetheless continues to turn the knob 7 , the tension in the strap will be limited by the pin 18 coming into abutment against the lower end of the slots 19 .
The strap 11 now has two taut strand parts. One strand part 11 A, to the right in FIG. 2, lying between the point 21 A where, on this side, the strap leaves the filter 2 at a tangent, and the distal point 22 A of its region of contact with the right-hand zone 14 A (FIG. 5 ); and a left-hand strap part 11 B, defined in a similar way. The zone 14 A lies on the same side as the geometric axis 16 with respect to the axis X—X and the distal end 22 A is further from the axis X—X than is the geometric axis 16 .
The operator then pushes the rod 6 /knob 7 assembly in the counterclockwise direction (arrow F 2 in FIG. 3 ). The sawteeth on the bearing face 20 of the shoe get a firm grip on the filter, and this action causes the wrench and the filter to rotate as one about the axis O (FIG. 3 ).
This is because, by virtue of the offset position of the axis 16 with respect to the axis X—X, the axis 16 thus being closer to the point 22 A than to the point 22 B, the distance 21 A- 22 B tends to increase more than the distance 21 A- 22 A tends to decrease, which means that the strap 11 is more taut.
During this phase of pushing towards the right (arrow F 2 in FIG. 3 ), the resistance to the unscrewing of the filter may cause the handle to pivot slightly with respect to the shoe about the axis 16 , but this pivoting is limited by the tension in the strap or by the pin 18 coming back into abutment with the top end of the slots 19 .
It can thus be seen that if θ represents the algebraic angle between, on the one hand, the axis Z—Z parallel to the axis X—X and passing through the axis 16 and, on the other hand, the straight line Y—Y which connects the center O of the filter to the axis 16 , the positive direction being that of the force in the direction F 2 , (counterclockwise in the drawings), then:
during the phase of tightening the strap around the filter, θ increases, and
during the pushing in the direction F 2 , θ tends to decrease.
After the filter has been rotated counterclockwise through a certain angle, for example limited by surrounding engine parts, the operator pushes the rod 6 - knob 7 assembly in the opposite direction F 1 (FIG. 4 ).
The distance 21 B- 22 B tends to decrease more than the distance 21 A- 22 A tends to increase, which means the strap 11 is less taut. Bearing in mind, in addition, the orientation of the sawteeth on the shoe, the entire tool slips about the filter 2 in the clockwise direction.
The wrench 1 therefore has a “ratchet” effect, which allows the handle to be moved back and forth a number of times to unscrew the filter 2 through several successive angles.
In the example described, the two stops for the pin 18 limit the angle θ to the range of zero to 25°. For each diameter of filter, there is a range of tightening values, and therefore a range of values of θ after tightening (FIG. 2 ), for which the ratchet effect is obtained. In the example in question, the amplitude of this range is about 10 to 15°. It depends on the geometry and on the coefficient of friction between the shoe and the filter.
It is important to note that as the spring 17 constantly presses the shoe against the filter, the angular offset which occurs between the shoe and the handle during the return or “ratchet back” movement is instantly taken up as soon as the action in the direction F 1 stops. The tool is thus particularly ergonomic because it requires no significant twist of the wrist, after the return movement, to begin the next turning operation on the filter.
In the embodiment of FIG. 5, the handle is embodied by a tubular handle body 23 , for example made of plastic, especially filled with reinforcing fibers, fitted onto the base 4 at one end and onto the knob 7 at the other. The exterior surface thereof is an extension of that of the body 23 .
In addition, the bearing surfaces 14 are asymmetric with respect to the axis X—X, the surface 14 A on the drive side being further from the knob 7 than the opposite surface 14 B. As before, the axis 16 is offset with respect to the axis X—X of the handle and is closer to the point 22 A than to the point 22 B irrespective of the diameter of the filter 2 in the range of diameters envisaged. In other words, the axis 16 is offset (to the right in FIG. 5) with respect to the mid-line X′—X′ of the segment 22 A- 22 B, as before. The zone 14 A lies on the same side as the geometric axis 16 with respect to the straight line X′—X′, and the distal end 22 A is further from this straight line X′—X′ than is the geometric axis 16 .
In order to permit the strap to be changed, the body 23 comprises, near to the base 4 , two opposed orifices 24 which allow a screwdriver to access the screws 13 when the nut 10 is in its uppermost position.
In this embodiment, the shoe 15 is made of a stack of metal sheets riveted together at 25 . As an alternative, the two outermost sheets may be the two legs of a sheet bent into a U with one or more additional sheets forming spacer pieces inserted between them.
As an alternative, the surface 14 A may be closer to the knob 7 than the surface 14 B, provided that the axis 16 remains closer to the point 22 A than to the point 22 B. This has been depicted diagrammatically in FIG. 5 by a mid-line X″—X″ of the segment 22 A- 22 B which passes between the axis X—X of the handle and the axis 16 .
In another particularly simple embodiment (FIG. 6 ), the wrench according to the invention has neither any system for adjusting the strap nor any spring. The elements which correspond to the embodiment of FIGS. 1 to 4 and whose geometry remains the same, bear the same references, increased by 100.
The wrench consists of:
a rigid body 103 forming a handle 123 , base 104 with its bearing surfaces 114 and yoke 105 . This body may be molded as a single piece or may consist of two molded pieces assembled, for example by two screws, along a vertical plane of connection;
a pin 116 borne by the yoke 105 and on which the shoe 115 is freely articulated; and
a strap 111 , at least one end part of which has a number of aligned orifices 27 .
On each surface 114 , the base 104 has a protruding stub 28 , which can be received in an orifice 27 . Each pair of orifices corresponds to a predetermined diameter of filter. In addition, a pin 118 borne by the shoe and passing through two arc-shaped slots 119 in the yoke 105 limits the angular travel of the shoe, in both directions, about the pin 116 .
Such an embodiment is particularly well suited to repetitive work performed on filters which all have the same diameter.
Of course, as an alternative, the tool may be equipped with a set of straps, each having a single orifice 27 at each end, each strap corresponding to a predetermined filter diameter.
As an another alternative, at least one of the stubs 28 may be provided at the top of the handle 123 , as shown in chain line in FIG. 6 .
It will be understood that it is possible to add a spring 17 to this embodiment.
In another embodiment which has not been depicted, the axis of pivoting of the shoe may be purely geometric without being embodied by a pin such as 16 . For that, all that is required is for the lower surface of the shoe to have a convex cylindrical shape which in cross section is in the shape of an arc of a circle and to cooperate with a mating concave guide surface provided on the body 3 .
FIGS. 7 and 8 show the external appearance of the strap wrench of FIG. 5, associated with filters of minimum and maximum diameters.
It will be observed that over its main length, the body 23 has a roughly elliptical cross section with its major axis in the overall plane of the strap. This cross section gradually becomes a circular cross section in the distal end part of the body 23 , adjacent to the knob 7 .
The knob 7 has flutes 29 to make it easier to grasp, and the body 23 has a number of recesses 30 and bears an arrow 31 which indicates the direction of drive. The flutes 29 allow the operator to identify the knob 7 of the body 23 unsighted, this being an effect which may be enhanced by the use of a substance which has a markedly different feel.
It will be understood that in each of the embodiments, the strap wrench according to the present invention can be used for screwing or for unscrewing, simply by turning it over.
FIGS. 9 and 10 show the external appearance of a slightly modified version of the tool in which the shoe 15 has sawteeth only in its two circumferential end regions. Furthermore, this shoe is made by bending a metal sheet into the shape of a U and inserting spacer pieces 32 , as described earlier.
FIG. 11 depicts an alternative form in which the handle body 23 consists of two half shells 23 A, 23 B, for example made of lightweight alloy or made of plastic, particularly filled with reinforcing fibers. The front parts of these shells together form the base 4 and the yoke 5 , the base being defined by superimposed perforated respective projections 4 A, 4 B formed integrally with the half shells. The plain front part 8 of the rod 6 passes through the holes in these two projections and is held axially therein by a snap ring 33 located between the projections 4 A and 43 and which snaps into a groove 34 in the part 8 . The nut 10 is guided in its translational movement by longitudinal reliefs inside the half shells. The lower ends of the two half shells are held together by an end skirt 7 A of the knob 7 pushed over them.
Dismantling may be achieved simply by pulling the knob 7 downwards, or as follows.
The knob 7 is fully unscrewed, which causes the nut 10 to move right up until it butts against the projection 4 A. By continuing to unscrew, the rod 6 is pushed downwards, which parts the snap ring 33 and releases the rod. The knob-rod assembly can then be lowered, and the two half shells parted.
Likewise, assembly may be achieved either by pushing the tip of the rod directly through the projections 4 A and 4 B or by first of all closing the two half shells around the rod 6 and the nut 10 and then by screwing the knob 7 . The nut 10 therefore moves down, butts against an internal collar 23 C, 23 D of the half shells, then continued screwing causes the rod 6 /knob 7 assembly to rise so that the tip of the rod passes through the projections 4 A and 4 B. At the end of its travel, the snap ring snaps into the groove in the rod and the skirt 7 A of the knob fits into position.
In the alternative form of FIGS. 12 and 13, the sawteeth of the shoe 15 are distributed in two regions 20 A, 20 B of the bearing face 20 , with clearance between them. The surfaces 25 A, 25 B tangential to the teeth in each of these regions may be planar as depicted, but may also be convex cylindrical or concave cylindrical with a radius larger than the largest radius of filter 2 . The combination of the surfaces 25 A and 25 B is such that for the most common filters in the range, one tooth and one tooth alone 26 A, 26 B of each region is in contact with the filter.
As can be seen clearly in FIG. 13, each tooth 26 A, 26 B has a trapezoidal overall shape with, to the left, a surface 27 A, 27 B which forms, with the surface 25 A, 25 B a relatively large angle α, followed by a surface 28 A, 28 B which forms, with the surface 25 A, 25 B, a relatively small angle β. The right-hand flank 29 A, 29 B of the tooth is almost at right angles to the surface 25 A, 25 B and connects to the surface 28 A, 28 B of the next tooth via a rounded portion 30 A, 30 B.
The teeth 26 A, 26 B are cut in two shots, i.e. a first-shot to give the overall shape of the teeth, and the second shot to cut out the part 28 A, 28 B of the tooth. The second cutting operation is intended to leave a tooth arris, the width of which is equal to the tolerance on the accuracy of the second cut with respect to the first.
It will be understood that in each embodiment, the strap wrench according to the invention provides one-way drive of the wrench by virtue of a toggle joint effect. The point of articulation of this toggle joint is the axis 16 or 116 , one side is the segment 0 - 16 or 0 - 116 , and the other side is a segment which extends from the axis 16 , 116 to a point secured on the handle of the wrench, which, in the examples described, is close to the axis of the handle and to the surfaces 14 , 14 A- 14 B or 114 .
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A one-way drive strap wrench having two strand parts ( 11 A, 11 B) and a shoe ( 15 ) for bearing against an oil filter ( 2 ). The shoe is pivotally mounted about a laterally offset axis ( 16 ). The wrench is particularly adapted for the fitting and removal of motor vehicle oil filters.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. Provisional Patent Application No. 61/504,948, entitled “Asynchronous Power Disconnect,” filed on Jul. 6, 2011, the entire contents of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] The disclosed subject matter is generally related to network on chip (NoC) design.
BACKGROUND
[0003] One valuable feature (among many others) of modern network-on-chips (NoCs) is the ability to run part of the network at a first clock frequency and part of the network at a second clock frequency. This allows part of the network with high data transfer bandwidth requirements to run fast while other parts run more slowly, easing the timing closure challenge for engineers and electronic design automation (EDA) tools. Separate clock domains also allow parts of a chip to run at different frequencies depending on the data processing requirements, using a slower clock frequency to save dynamic power while data processing requirements are relatively low. Separate clock domains are also useful when parts of the network are a significant distance apart on the chip because clock tree insertion and balancing across significant distances is difficult. Allowing parts of the NoC to run just with localized clocks avoids that difficulty.
[0004] A network on chip employs a unit of logic known as a clock domain adapter to transfer data correctly between logic in two different clock domains. In particular, a clock domain adapter for transferring data between asynchronous clock domains is known as an asynchronous clock domain adapter. The logic of an asynchronous clock domain adapter generally comprises two portions: a sender that sends data and a receiver that receives data.
[0005] FIG. 1 is a simplified block diagram illustrating an example asynchronous clock domain adapter unit 100 . The adapter unit 100 includes circular buffer 102 , multiplexer 104 , write control 106 and read control 108 . Data sender logic is clocked in a sending clock domain while data receiver logic is clocked in a receiving clock domain. In adapter unit 100 , the signals that pass between the sender and receiver include data elements in circular buffer 102 , also known as a bisynchronous first-in-first-out (FIFO) buffer. The circular buffer 102 can be coupled to the multiplexer 104 . The multiplexer 104 outputs data elements from the circular buffer 102 based on a read pointer (RdPtr) value. The write control unit 106 is configured to control a Gray coded write data counter for generating a write count (WrCnt). The read control unit 108 is configured for controlling a Gray coded read data counter 106 for generating a read count (RdCnt) and the read pointer (RdPtr).
[0006] Another valuable feature of an asynchronous clock domain adapter is the ability to power off part of the network-on-chip without causing functional failure or data loss or corruption for the rest of the chip. The ability to power off part of a chip is useful for saving power. Power-off is typically used when a processing function is not required. For example, a video codec intellectual property (IP) block might be powered off in a mobile device application processor when no video is being played.
[0007] The set of logic that is powered on or off together is known as a power domain. Within a wake-up sequence, some (usually most) of the logic in the power domain is reset to a known state. This enables the engagement of an appropriate data transfer protocol from a predictable state of operation. In conventional power disconnect units the logic on both sides (the already-awake and the waking-up) run on a common clock. This ensures that one side does not take on an unpredictable state while the other side is beginning to engage the communication protocol.
[0008] In conventional NoCs, an asynchronous clock domain adapter sender and an asynchronous clock domain adapter receiver can reside in the same power domain. If one is running while the other is powered off the adapter unit can take on an unpredictable state, leading to data loss or instability. Specifically, when an asynchronous clock domain adapter unit is powered on and reset, the state of WrCnt in the sender and the state of WrCnt in the synchronization registers of the receiver are both the same and the state of RdCnt in the receiver and RdCnt in the synchronization registers of the sender are the same and RdPtr is known to the write control unit 106 . If one wakes up and is reset while the other is still running they would tend to reset with unsynchronized pointers, leading to data being sent twice or data being lost or other unpredictable behavior.
[0009] In other words, an asynchronous clock domain adapter unit and a power disconnect unit may operate correctly in series if there is no asynchronous clock domain adapter between the master and slave sides of a power disconnect unit and there is no power disconnect unit between the asynchronous clock domain adapter sender and the asynchronous clock domain adapter receiver.
[0010] When laying out a chip it is often desirable to have logic within a single clock domain localized within a common region. This is because it is difficult to insert and balance a clock tree when the clock nets extend over significant distances. It is also often desirable to have logic within a single power domain localized within a common region. This is because it is difficult to comingle the wiring carrying power from many different power supplies within a shared region of the chip. Basically, localization is valuable, and increasingly so as modern chips are designed with increasingly many power domains and increasingly many clock domains.
[0011] Furthermore, it is valuable to have a small number of network-on-chips. This is because the complexity of transferring data through a network-on-chip occurs at the edges of the network where packets are encoded and decoded and all of the interconnecting logic is relatively simple. The fewer network-on-chips, the less logic overhead is required for encoding and decoding packets. Such logic is expensive in silicon die area, logic path delay, and clock cycles of latency for transferring data. As a result, network-on-chips must span multiple, and usually many, clock domains and power domains.
[0012] FIG. 2 illustrates a network-on-chip with a physical distance between sides of a power disconnect unit downstream of an asynchronous clock domain adapter unit. An impediment to localization arises when an asynchronous clock domain adapter and a power disconnect unit are placed in series within a data link in a network-on-chip. FIG. 2 shows an initiator IN that request a write transaction to send data to a target TA through an asynchronous clock domain adapter sender SE REQ in the request path, an asynchronous clock domain adapter receiver RE REQ in the request path, a downstream disconnect unit master side manager MA, and a disconnect unit slave side manager SL. Response data is returned through SL and MA and an asynchronous clock domain adapter sender SE RSP and an asynchronous clock domain adapter receiver RE RSP. The physical placement of the units is such that MA and SL are far apart (indicated by the dashed line). In this configuration the units have good localization in the power domains but have poor localization in clock domains. The clock signal of clock domain Y spans the significant distance between the logic of MA and SL. This configuration challenges clock tree insertion.
[0013] FIG. 3 illustrates a network-on-chip with a physical distance between senders and receivers of asynchronous clock domain adapter units upstream of a power disconnect unit. More particularly, FIG. 3 shows a configuration of the same components but with MA and SL close together and with SE REQ separated from RE REQ by a significant distance and SE RSP separated from RE RSP by a significant distance. This configuration is preferable to that of FIG. 2 for clock tree insertion because no clock signals spans a significant distance. However, this configuration requires the power supply of power domain A to span the significant distance, which challenges supply rail routing.
[0014] FIG. 4 illustrates a network-on-chip with a distance between senders and receivers of asynchronous clock domain adapter units downstream of a power disconnect unit. More particularly, FIG. 4 shows a configuration in which the power disconnect unit is upstream of the asynchronous clock domain adapters in the request data flow. The asynchronous clock domain adapter unit senders and receivers are placed at a significant distance. This configuration suffers a supply rail routing challenge.
[0015] FIG. 5 is a network-on-chip with a distance between sides of a power disconnect unit upstream of an asynchronous clock domain adapter unit. More particularly, FIG. 5 shows a configuration with the same components but with the power disconnect unit master side manager and slave side manager placed at a significant distance. This configuration suffers a clock tree insertion challenge.
[0016] Some network-on-chips do not include a response path. For such configurations FIGS. 2-5 are applicable, but without the SE RSP and RE RSP components and no response data path.
[0017] FIG. 6 illustrates an example power disconnect unit. Request data from master to slave and response data from slave to master are connected as in any system of a single power domain, except that they are separated by power isolation cells. The SocketConn signal indicates to the slave that the master is connected and can send traffic. The SlvRdy signal indicates to the master that the slave can be safely powered off without the loss of transactions in flight. SocketConn and SlvRdy are also connected between master and slave through power isolation cells. The clock signal is generated in the power-on domain and connected to the power-off domain through an isolation cell.
[0018] The disclosed invention pertains, particularly, to networks of clocked logic. A unit with an ability to correctly transfer data between logic in a first clock domain and logic in a second clock domain is known as an asynchronous clock domain adapter. This is because the two clocks have no synchronized relationship to each other. The invention does not pertain to networks of asynchronous logic, also known as self-timed logic. Such networks transfer data without a corresponding clock signal.
SUMMARY
[0019] The disclosed implementations are directed to a power disconnect module that integrates an asynchronous clock domain crossing. In some implementations, a power disconnect unit within a data transport topology of a NoC includes an asynchronous clock domain adapter unit inserted between a master side manager unit and a slave side manager unit. This configuration allows for the master and slave side managers of the power disconnect unit to be placed physically far apart on the chip, relieving the need to route long power rail signals on the chip. A response data path and associated asynchronous clock domain adapter unit is optionally included on the chip. A path to bypass the asynchronous clock domain adapter units is optionally included on the chip to enable a fully synchronous mode of operation without the data latency cost of the asynchronous adapter unit.
DESCRIPTION OF DRAWINGS
[0020] FIG. 1 illustrates an asynchronous clock domain adapter unit.
[0021] FIG. 2 illustrates a power disconnect unit with a physical distance between sides of a power disconnect unit downstream of an asynchronous clock domain adapter unit.
[0022] FIG. 3 illustrates a power disconnect unit with a physical distance between senders and receivers of asynchronous clock domain adapter units upstream of a power disconnect unit.
[0023] FIG. 4 illustrates a power disconnect unit with a physical distance between senders and receivers of asynchronous clock domain adapter units downstream of a power disconnect unit.
[0024] FIG. 5 illustrates a power disconnect unit with a physical distance between sides of a power disconnect unit upstream of an asynchronous clock domain adapter unit.
[0025] FIG. 6 illustrates a conventional power disconnect unit.
[0026] FIG. 7 is an example power disconnect unit with a physical distance between the sides of a power disconnect unit and a distance between the senders and receivers of asynchronous clock domain adapter units.
[0027] FIG. 8 illustrates an example power disconnect unit with a mode to bypass the asynchronous clock domain adapter unit.
[0028] FIG. 9 illustrates an example power disconnect unit that includes two asynchronous clock domain adapter units.
[0029] FIG. 10 illustrates an example timing diagram for a master domain power off and power on sequence of a power disconnect unit engaging data transfer protocol.
[0030] FIG. 11 illustrates an example timing diagram for a slave domain power off and power on sequence of a power disconnect unit engaging data transfer protocol.
DETAILED DESCRIPTION
[0031] A network-on-chip is disclosed that includes an asynchronous clock domain adapter unit inserted between a master side manager and a slave side manager of a power disconnect unit. An example of such a network-on-chip is shown in FIG. 7 .
[0032] FIG. 7 is an example power disconnect unit with a physical distance between the sides of a power disconnect unit and a physical distance between the senders and receivers of asynchronous clock domain adapter units.
[0033] In some implementations, a power disconnect unit 700 can include an initiator 702 (IN) connected to a target 704 (TA) through a request datapath and a response datapath. IN and TA can be independently powered on and off within power domains A and B respectively. The power disconnect protocol can be between a master side manager 706 (MA) and a slave side manager 708 (SL). In this example, within the power disconnect unit 700 the request datapath passes through an upstream sender 710 (SE REQ) and a downstream receiver 712 (RE REQ) of an asynchronous clock domain adapter unit. Likewise, within the power disconnect unit 700 the response datapath passes through a sender 714 (SE RSP) and a receiver 716 (RE RSP) of an asynchronous clock domain adapter unit. The upstream and downstream components are physically placed at a significant distance apart (indicated by the dashed lines). The upstream components can operate within a single power domain A and clock domain X. The downstream components can operate within a single power domain B and clock domain Y. As a result, no clock signal passes the significant distance between components and no power rail wires are routed the significant distance between components. As a result, the logic of all units is localized, avoiding the challenges of significant distance clock tree insertion and significant distance power rail routing.
[0034] FIG. 8 illustrates an example power disconnect unit with a mode to bypass the asynchronous clock domain adapter unit. More particularly, FIG. 8 shows another example power disconnect unit 800 comprising a request path but no response path. A master side manager 802 (MA) sends data through an upstream router 804 (UR) that, in one mode, sends data through a sender 806 (SE) and a receiver 808 (RE) of an asynchronous clock domain adapter to a downstream multiplexer 810 (DM) that passes the data to slave side manager 812 (SL) and, in another mode, sends data directly through DM 810 to SL 812 , bypassing SE 806 and RE 808 . Such an embodiment allows the chip to avoid data delay inherent to an asynchronous clock domain adapter unit when running in a mode in which clock domain X and clock domain Y are synchronized.
[0035] FIG. 9 illustrates an example power disconnect unit that includes two asynchronous clock domain adapter units. More particularly, FIG. 9 shows a more detailed diagram of the example implementation of FIG. 7 . In FIG. 9 , request data from the power disconnect unit master side manager 706 to the slave side manager 708 and response data from slave side manager 708 to master side manager 706 are connected through asynchronous clock domain adapter unit senders 710 and receivers 712 , except that they are separated by power isolation cells 902 .
[0036] In this example, the SocketConn signal indicates to the slave that the master is connected and can send traffic. The ConnAck signal is the resynchronized copy of SocketConn, plus 2 cycles. It is resynchronized in the master side manager 706 and resets the asynchronous clock domain adapter sender 710 , once the power disconnect unit slave side manager 708 has done the same on the asynchronous clock domain adapter receiver 712 . The SlvRdy signal indicates to the master side manager that the slave side manager can be safely powered off without the loss of transactions in flight. SocketConn, ConnAck, and SlvRdy are also connected between the master side manager 706 and slave side manager 708 through power isolation cells 902 . The clock signals on the master side and slave side are generated separately (and physically distant) in their respective power domains. The asynchronous clock domain adapter senders 710 and 714 and receivers 712 and 716 each receive a power on signal 904 that, when asserted, resets the component logic. The master side manager 706 generates ReqPwrOn to reset the request path asynchronous clock domain adapter sender 710 and generates RspPwrOn to reset the response path asynchronous clock domain adapter receiver 712 . The slave side manager 708 generates ReqPwrOn to reset the request path asynchronous clock domain adapter receiver 712 and generates RspPwrOn to reset the response path asynchronous clock domain adapter sender 714 .
[0037] FIG. 10 is an example timing diagram for a master domain power off and power on sequence of a power disconnect unit engaging a data transfer protocol. Referring to the implementation shown in FIG. 9 , after the system level power manager requests power-off of the master power domain, the following steps occur:
[0038] 1. The power disconnect unit master side manager fences new requests. The process of fencing includes stalling the request path or responding with an error signal;
[0039] 2. The power disconnect unit master side manager waits until it has drained (received all pending) responses from the power disconnect unit slave side manager for all pending requests;
[0040] 3. The power disconnect unit master side manager deasserts SocketConn. It also disables the response asynchronous clock domain adapter receiver by deasserting MstRspPwrOn. This prevents spurious transmissions in the response path caused by the SE RSP reset that will occur later;
[0041] 4. The power disconnect unit slave side manager disables the response asynchronous clock domain adapter sender by deasserting SlvRspPwrOn. This resets the SE RSP unit, including RdCnt and the WrCnt synchronization registers. The power disconnect unit slave side manager also disables the request asynchronous clock domain adapter receiver by deasserting SlvReqPwrOn. This prevents spurious transmissions in the request path caused by the SE REQ reset that will occur later;
[0042] 5. The power disconnect unit slave side manager deasserts ConnAck to indicate that it is ready for the power disconnect;
[0043] 6. The power disconnect unit master side manager disables the request asynchronous clock domain adapter sender by deasserting MstReqPwrOn. This resets the SE REQ unit, including WrCnt and the RdCnt synchronization registers; and
[0044] 7. The system level power manager disconnects the power supply from the master domain. SocketConn remains undriven while SlvRdy and ConnAck are held by the power disconnect unit slave side manager.
[0045] When the system level power manager requests wake-up of the master power domain, it connects power and deasserts reset. The following steps occur for the wake-up:
[0046] 1. The power disconnect unit master side manager asserts SocketConn. It also resets and enables the response asynchronous clock domain adapter receiver by asserting MstRspPwrOn. At this step, the power disconnect unit master side manager is able to receive request packets, but will assert backpressure upstream to stall traffic;
[0047] 2. The power disconnect unit slave side manager receives SocketConn and asserts ConnAck. It also resets and enables the response asynchronous clock adapter sender by asserting SlvRspPwrOn. It also resets and enables the request asynchronous clock adapter receiver by asserting SlvReqPwrOn;
[0048] 3. The power disconnect unit master side manager receives ConnAck and enables and resets the request asynchronous clock domain adapter sender by asserting MstReqPwrOn. It also stops stalling and request data transfers and begins sending the requests through the request asynchronous clock domain adapter unit; and
[0049] 4. The power disconnect unit slave side manager receives data transfer responses and passes them through the asynchronous clock domain adapter receiver to the power disconnect unit master side manager.
[0050] FIG. 11 is an example timing diagram for a slave domain power off and power on sequence of a power disconnect unit engaging data transfer protocol. When the system level power manager requests power-off and power-on of the slave domain, the steps are the same as for power-off and power-on of the master domain except that, as shown in FIG. 11 , the power disconnect unit slave side manager can signal to the power disconnect unit master side manager that it wants to power off and wants to power on. This can be done with the SlvRdy signal before step 1 in each procedure above. Also, when the slave domain is powered off, the power disconnect unit master side manager holds SocketConn and SlvRdy and ConnAck remain undriven.
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A power disconnect unit within a data transport topology of a NoC includes an asynchronous clock domain adapter unit inserted between a master side manager unit and a slave side manager unit. This configuration allows for the master and slave side managers of the power disconnect unit to be placed physically far apart on the chip, relieving the need to route long power rail signals on the chip. A response data path and associated asynchronous clock domain adapter unit is optionally included on the chip. A path to bypass the asynchronous clock domain adapter units is optionally included on the chip to enable a fully synchronous mode of operation without the data latency cost of the asynchronous adapter unit.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. Pat. No. 12/631,835 filed Jan. 8, 2010, the contents of which are herein incorporated by reference.
[0002] This application is related to U.S. application Ser. No. 13/022,178, filed Feb. 7, 2011; U.S. application Ser. No. 13/329,596, filed Dec. 19, 2011, now U.S. Pat. No. 9,044,594; and U.S. application Ser. No. 14/727,140, filed Jun. 1, 2015, the contents of each are herein incorporated by reference.
TECHNICAL FIELD
[0003] This application relates to laser medical devices and its use in pain medicine.
BACKGROUND OF THE INVENTION
[0004] Low level laser therapy (LLLT), also known as photobiomodulation, cold laser therapy, and laser biostimulation, is a medical and veterinary treatment, which uses low-level lasers or light-emitting diodes to stimulate or inhibit cellular function. LLLT uses light sources such as lasers or LEDs to deliver light of certain wavelengths at certain intensities to affect tissue regeneration, inflammation, or pain. Existing deep tissue lasers today use heat generation to cause a non-selective action destroying non-specific tissue on contact.
SUMMARY
[0005] In general, one aspect of the subject matter described in this specification may include using a deep tissue low intensity laser (DT-LIL) capable of producing cell resonance within a nerve cell that can selectively cause destruction of the nerve cells without affecting the surrounding tissues. The deep tissue low intensity laser treatment (DT-LILT) selectively destroys nerve cells on contact using absorption and cell resonance. DT-LILT does not generate sufficient heat to destroy tissue, allowing selective destruction when nerve cells selectively absorb the DT-LILT wavelength. Thus, selective deep tissue low intensity laser ablation (DT-LILA) of the nerves, or deep tissue low intensity laser neuroablation (DT-LILNA) takes place.
[0006] The selection of laser wavelength may depend on the absorption characteristics of the nerve cells. Heat may or may not be generated as the selective destruction takes place by cell resonance rather than by heat coagulation. The use of deep tissue low intensity laser neuroablation (DT-LILNA) is described herein and is different from other medical or tissue lasers that use heat generation. Clinical applications include treating chronic pain, soft tissue injury, wound healing and nerve regeneration.
[0007] Definition of Terms:
[0008] 1. DT-LILT: Deep Tissue Low Intensity Laser Treatment or Therapy.
[0009] 2. DT-LIL: Deep Tissue Low Intensity Laser.
[0010] 3. DT-LILA: Deep Tissue Low Intensity Laser Ablation.
[0011] 4. DT-LILNA: Deep Tissue Low Intensity Laser Neuroablation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 illustrates a schematic diagram of an example laser delivery system for use with DT-LILT.
[0013] FIG. 2 illustrates an AP x-ray view of a lumbar facet joint, a lamina and a spinous process.
[0014] FIGS. 3A-3G illustrate single lumbar facet joints with various laser point configurations for DT-LILT.
[0015] FIG. 4 illustrates an example laser delivery system for use with DT-LILT.
[0016] In the drawings, like reference numbers represent corresponding parts throughout.
DETAILED DESCRIPTION
[0017] Current deep tissue medical lasers are typically high intensity lasers, with output powers usually around 100 mW or above, that generate heat to destroy contact tissue using techniques such as hemo-coagulation. However, these deep tissue medical lasers lack sufficient selectivity or specificity to destroy contact tissue without causing collateral damage to surrounding tissue. Traditional low level laser therapy (LLLT) techniques also lack sufficient specificity. Current LLLT techniques use indirect pain relief techniques such as minimal heat generation, vasodilatation or metabolic changes. These lead to temporary pain relief because they do not destroy problematic pain nerves that cause long-term pain.
[0018] The deep tissue low intensity laser treatment (DT-LILT) disclosed in this application selectively destroys nerve cells on contact using the phenomenon of absorption and cell resonance. DT-LILT does not generate heat, or the heat generated is not sufficient to destroy tissues, therefore selective destruction is brought upon by cell resonance when the nerve cells selectively absorb the DT-LILT laser wavelength. By causing destruction of nerve cells in this manner, DT-LILT can provide long-term pain relief extending for many months.
[0019] FIG. 1 illustrates a schematic diagram of an example laser delivery system 100 for use with DT-LILT. For example, the system 100 may include a laser generator 102 , a laser fiber 104 , a laser fiber fixator 106 , and a needle 108 . The system 100 may be used in DT-LILT by performing absorption and cell resonance to selectively destroy nerve cells without affecting the surrounding tissues.
[0020] In some implementations, the system 100 is used to specifically destroy nerve cells to provide long-term pain relief This is performed by causing absorption of specific wavelengths by nociceptive nerves when DT-LILT is directly applied to a pain generating area, bringing about the physiologic action of neuroablation (DT-LILNA) of the pain nerves. In such implementations, the DT-LILT may be minimally invasive and designed to be used within the pain generating area. For example, DT-LILT may be applied to specific areas of the spine as shown in FIGS. 3A-3G . The system 100 may be used to cause destruction of tissue without heat generation. For example, laser generator 102 may be a DT-LIL with power output less than 5 mW to allow deep tissue application. In some implementations, the DT-LIL may fall under laser classification 3R or below.
[0021] In one implementation, the system 100 includes the laser generator 102 capable of generating light of wavelength in the 690 nm to 710 nm range, the laser fiber 104 with diameters between 0.7 and 0.5 mm, and the laser fiber fixator 106 coupled with the needle 108 using a luer lock mechanism. The needle 108 may be a common Quincke spinal needle. The fixation between the laser fiber 104 and the spinal needle 108 can also be achieved by making the laser fiber and the spinal needle as one non detachable unit.
[0022] In some implementations, the laser generator 102 produces a laser with wavelength between 700 nm to 705 nm, laser output average power between 4 mW and 6 mW (with range between 1 mW and 6 mW) , a laser pulsation at nanosecond or picosecond intervals, and timer controlled between 5 seconds and 10 seconds.
[0023] In some implementations, the nerve tissue consists of lipids that absorb the above laser wavelengths without impacting surrounding non-nervous tissue. For example, the laser generator 102 may have a wavelength between 690 nm and 710 nm with an optimal absorption at 703 nm, and with low output and high pulsation, which is absorbed by the nociceptive nerves. In such an example, using a 703 nm laser with the low output and high pulsation causes the nociceptive nerves to be selectively destroyed leaving surrounding tissue intact without heat generation.
[0024] In some implementations, the needle 108 is a fine needle that is 22G or smaller to deliver the laser treatment deep into the tissue. In some implementations, the needle 108 is 25G with a 0.5 mm inner diameter to fit a 300 μm laser fiber 104 and insert the laser fiber 104 below the body surface of a human patient. The fine needle 108 facilitates reaching tissue areas of treatment that may lie deep from the body surface and the inserted laser fiber facilitates the laser delivery to the area of treatment. In some implementations, the needle 108 may be a Quincke spinal needle. The fine needle 108 may provide cost savings as compared to heavier and bigger conduits for laser delivery.
[0025] In some instances, the design of the needle 108 includes laser fiber 104 embedded within the cannula of the needle to form a non-detachable unit. In some instances, the system 100 includes a laser fiber fixator 106 with a luer lock mechanism to facilitate the attachment of different-sized syringes to various sized needles. For example, the laser fiber fixator 106 with a luer lock mechanism may be used to attach the needle 108 , which may be a Quincke spinal needle, to the laser fiber 104 , which fixes the laser fiber within the needle and prevents movement of the fiber during laser delivery. In some implementations, the laser fiber fixator 106 includes a tuohy borst adapter with a blue cap and a male luer lock connector with a spin lock. In such implementations, the dimensions of the laser fiber fixator 106 may be between 2-6 FR (0.026 in-0.083 in) (0.66 mm-2.11 mm) (22-12 Gauge). In such implementations, the material of the laser fiber fixator 106 may be acrylic, polycarbonate, or silicone.
[0026] In some implementations, the system 100 may be used to perform a method that includes an intra-operative treatment using facet joint neuroablation, also known as medial branch neuroablation, as represented in FIG. 2 . For example, the method may use a simple AP x-ray view and pass a deep tissue low intensity laser to cause a DT-LILNA. In another example, the DT-LIL may cause a DT-LILA. This is in contrast to conventional neuroablation that is based on finding the medial branch nerve in an oblique/lateral X ray view and using heat or chemical substance to destroy the medial branch.
[0027] FIG. 2 illustrates an AP X-Ray view of lumbar facet joints 202 , a lamina 204 and a spinous process 206 . DT-LILT may be applied to specific areas of the spine as shown in FIG. 2 , using laser points as shown in FIGS. 3A-3G .
[0028] Although FIG. 2 shows the lumbar facet joint as laser points for the application of DT-LILT using the laser delivery system 100 , the laser points used in DT-LILT are also applicable to all facet joints, including thoracic and cervical facet joints. When the size of the facet joint is smaller, the laser points and the laser area for DT-LILT may reduce but the pattern of laser delivery remains the same.
[0029] FIGS. 3A-3G illustrate single lumbar facet joints with various laser point configurations for DT-LILT. Referring to FIG. 3A , laser points 312 may be made in eight points in a circular fashion around the facet joint 310 . Referring to FIG. 3B , laser points 322 may be made in a continuous circular fashion around the facet joint 320 . Referring to FIG. 3C , the laser points 332 may be made in continuous intermittent fashion around the facet joint 330 . Referring to FIG. 3D , the laser points 342 may be made in continuous cross fashion across the facet joint 340 . Referring to FIG. 3E , the laser points 352 may be made in continuous multiple cross fashion across the facet joint 350 . Referring to FIG. 3F , the laser points 362 may be made in continuous intermittent fashion 4 across the facet joint 360 . Referring to FIG. 3G , the laser points 372 may be made in a continuous intermittent fashion multiple across the facet joint 370 .
[0030] FIG. 4 illustrates an example laser delivery system 400 for use with DT-LILT. The laser delivery system 400 may be used for a medical procedure for treating reoccurring pain. In some implementations, the laser delivery system 400 is similar to the system 100 .
[0031] In some implementations, the system 100 or the system 400 includes specified operating parameters for DT-LILT. For example, the laser generator 102 generates a 703 nm wavelength laser with 2 nm specified range, has an average 4 mW output power with a 0.8 mW specified range and a peak output power at 40 nW with 8 nW specified range. The laser is pulsed at 25 ns and is timer controlled at 5 s or 10 s. The system 100 or the system 400 includes two types of laser fiber diameters at 200 micron and 300 micron, with a laser area of the tissue under treatment that is confined to the laser fiber diameter with less than 1 mm scatter.
[0032] The laser also operates on rechargeable batteries, does not require a dedicated power supply during operation, and is compatible with the North American 110-120 V/AC standard. The system 100 or the system 400 is also enclosed in a non-conducting insulated casing and does not require separate grounding during charging, operation, or both. In such implementations, because the laser has low output power, its use for pain treatment is safer than current deep tissue medical lasers with high intensity lasers.
[0033] The following sections describe an example DT-LILT procedure using the system 100 or the system 400 in some implementations. The DT-LILT procedure in these implementations does not involve use of sedation, general anesthetics, local anesthetics, or the use of oral or injectable drugs. The DT-LILT is performed bilaterally on the L5-S1 and L4-L5 face joints. During the procedure, a 25 G spinal needle is initially directed bilaterally at each of the L4-L5 and L5-S1 facet joints. Each facet joint is individually treated. Once the needle is embedded at the center of the facet joint, the laser fiber is inserted after removing the stylet. The DT-LILT generator is then switched on to deliver five seconds of laser energy.
[0034] In this manner, four facet joints are treated with one laser delivery point per facet joint with a five second laser delivery time and a 20 second total laser delivery time during the procedure. During the procedure, the patient is aware of the entire procedure to provide feedback. The patient may not feel discomfort other than from insertion of the needle.
[0035] During post procedure testing, which is performed to determine the effectiveness of the procedure in reducing or removing pain symptoms, pain resolution report from the patient is collected and the patient's ability to stand straight, flex the spine posteriorly are all evaluated. A Kemp test is also performed to assess the lumbar spine facet joints. A patient satisfaction score from a scale 0 to 100 (higher the score better the satisfaction) may be collected to determine pain reduction resulting from the procedure.
[0036] Results of test applications of DT-LILT indicated complete 100% resolution of pain symptoms after the procedure, with the patient able to stand straight and flex the spine posteriorly. The patient had negative Kemp test soon after the procedure. The patient also reported a satisfaction score of 100.
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Deep Tissue Low Intensity Laser Therapy or Treatment (DT-LILT) as described here is a novel methodology through which selective destruction of nociceptive (pain) nerves can be brought upon by a medical laser delivery system using the phenomenon of absorption and cell resonance. Using this method nerve cells that transmit pain can be selectively destroyed leaving the surrounding tissues intact as no heat is generated. The delivery system incorporates a fine needle through which a 703 nm (range 690 to 710) pulsed wave low intensity laser is delivered deep into the body, directly to the area of pain causing selective destruction of pain nerves. Laser devices based on this methodology should be used only by the physician or equivalent professional community since diagnosing and defining the area of pain is critical to providing successful pain relief.
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This is a continuation of application, Ser. No. 06/835,493, filed March 3, 1986 now U.S. Pat. No. 4,792,336.
BACKGROUND OF THE INVENTION
This invention relates to an implantable device composed of one or more bio-absorbable polymer(s) or combinations of bioabsorbable/non-absorbable polymer(s) for the repair or augmentation of connective tissue damaged by disease or injury. The devices shall serve as scaffolds for ingrowth and orientation of new fibrous connective tissue, (e.g. ligaments, tendons) in both intra-articular and extra-articular sites by maintaining structural stability during initial healing and then undergoing at least partial gradual absorption to prevent stress shielding and allow newly formed tissue to become correctly oriented and load bearing.
The invention includes several aspects of device design that are intended to provide for simulation of natural tissue function immediately after implantation and to support subsequent fibrous tissue ingrowth as well as orientation in the direction of natural loading. The devices are braided or woven into a flat tape geometry having the plurality of fibers aligned in parallel to form the axial warp. The physical/mechanical/chemical properties of all or part of the component fibers may be enhanced by a number of temperature/time/stress treatments. One or more adjacent plies of the device are used in surgery to achieve biomechanical properties approximately equivalent to the healthy tissue prior to being damaged. A swivel needle attachment system may be incorporated to facilitate handling and surgical placement of the devices. The interfibrillar space, that provides for initial tissue ingrowth, occurs as a result of the braiding/weaving process or may be enhanced by means of texturizing the yarns. Gradual bioabsorption, in whole or in part, provides for additional interfibrillar space to form during the healing period, and for fibrous tissue orientation to be induced as load is transferred from the weakened implant to the `neo-ligament` or `neo-tendon`.
The bioabsorbable materials, biocompatible nonabsorbable materials, physical and chemical combinations thereof, and the processes involved in fabricating them into the implantable devices are all included in this invention.
Ligaments and tendons are bands or sheets of fibrous connective tissue which provide support and stability to the musculoskeletal system. Relief of the pain and/or instability caused by damage to a ligament or tendon is currently achieved by techniques ranging from simple suturing to removal and replacement with other tissue or a permanent synthetic prosthesis. Although no single technique is appropriate for all situations, it is generally preferred to return the tissue to it's healthy, pre-damaged state as naturally as possible. Furthermore, it is highly desirable to reduce the need for activity restriction during the healing period. The permanent retention of implanted foreign materials is considered undesirable and should be minimized because it may result in stress shielding and subsequent atrophy of natural tissue, or the migration of the materials to other tissues and/or systems (i.e. lymphatic) may occur.
The state-of-the-art in ligament repair/reconstruction is considered to be the use of autogenous tissue grafts for augmentation or replacement of the damaged ligament. Portions of the patellar tendon, iliotibial band, semitendinosus tendon, and fascia lata are some of the most commonly used autogenous tissue grafts. Due to the undesirability of having to sacrifice one tissue and its associated function, in order to repair another, a number of synthetic, permanent total ligament prostheses and ligament augmentation implants are being tried in animals as well as clinically.
Several of the permanent ligament prostheses are fabricated so that the properties of a single synthetic material characterize the implant's response to in-vivo loading (see, e.g., U.S. Pat. Nos. 3,896,500; 3,953,896; 3,987,497; 3,988,783; and European Patent Application Nos. 51,954; 106,501; and 126,520, all of which are incorporated herein by reference). Although many of the aforementioned patents include more than one material in the structure of the body of the prosthesis, a single material determines the mechanical (tensile) properties while the secondary components are in the form of coatings, sheaths, etc. to improve biocompatibility or lubricity. While ligamentous tissue is a natural composite material exhibiting both compliant elasticity and high longitudinal strength, no single synthetic biocompatible material has this combination of properties. As a result, implants such as the ones listed above have tended to fail in animal or clinical trials either by material fatigue, creep (joint laxity), in-vivo degradation or by unacceptable restriction of joint motion.
A number of multi-component ligament prostheses (see, e.g. U.S. Pat. Nos. 3,797,047; 4,187,558; 4,483,023; and European Patent Application No. 122,744, all of which are incorporated herein by reference are more bio-mechanically compatible with the elasticity and strength requirements of natural ligament function but suffer from other shortcomings. Since they are designed to replace the natural ligament, any reparative tissue that forms at the site of the defect, is almost completely shielded from applied loads and therefore tends to resorb. The inevitable chemical and/or physical breakdown of these implants in-vivo, leads to catastrophic failure and a return to pre-operative instability, or worse, because no natural tissue repair has taken place. No ligament prosthesis, tried thus far in animals or humans, has yielded consistently acceptable joint stability without the occurence of implant breakdown, synovitis, and/or articular tissue damage during the first two years post operatively. The desired minimum post operative period of implant/joint stability is 10 years.
Attempts at a long-term `natural` tissue repair (by augmenting but not replacing the natural tissue) has been approached by the use of a variety of devices and techniques. The use of a permanent device for augmentation of an autogenous tissue transplant is described in "Experimental Mechanical and Histologic Evaluation of the Kennedy Ligament Augmentation Device", G. K. McPherson, Ph.D. et al., Clinical Orthopedics and Related Research, no. 196, pages 186 to 195, 1985, which is incorporated herein by reference. While the method of attachment allows the desired natural tissue repair to occur, the entire synthetic implant remains in situ; some interfibrillar mechanical breakdown has recently been reported, and a chronic foreign body response is observed even at 2 years following implantation. A biologically mechanically degradable augmentation device consisting of polyglycolic acid (herein abbreviated as PGA) -coated carbon fibers (U.S. Pat. No. 4,411,027) or polylactic acid (herein abbreviated as PLA) - coated carbon fibers (U.S. Pat. No. 4,329,743) has also met with limited success in obtaining a `natural` tissue ligament repair. Both of these patents are incorporated by reference. However, even though the polymer coating protects the brittle carbon fibers intra-operatively and is then safely absorbed by the body, the gross modulus and elasticity mis-match between the carbon fibers and the new ligamentous tissue that infiltrates the implant, results in fragmentation of the carbon fibers. This mechanical breakdown of the carbon fibers does serve to transfer load to the new tissue as desired, but serious concerns persist regarding the eventual disposition of the carbon fiber fragments. Finally, as described in "Acute Anterior Cruciate Ligament Injury and Repair Reinforced with a Biodegradable Intraarticular Ligament", H. E. Cabaud, M.D. et al., The American Journal of Sports Medicine, vol. 10, pages 259 to 265, 1982; and "A Partially Biodegradable Material Device for Repair and Reconstruction of Injured Tendons: Experimental Studies", W. G. Rodkey, D.V.M. et al., AAOS Meeting, 1985, both of which are incorporated herein by reference, and the comparative examples A to F herein, biodegradable implants consisting of PGA and polyester (specifically Dacron™) have been tried as repair/augmentation devices for obtaining `natural` ligament and tendon healing. The results of this work indicate that PGA does not retain its properties long enough, in-vivo, and that any tissue that does infiltrate the permanent polyester fiber component does not achieve adequate strength or joint stability due to lack of tissue orientation and excessive ligament/tendon lengthening. The relatively short strength retention period of PGA, will apparently not allow the elimination of joint immobilization that is currently necessary following ligament repair or reconstruction.
The surgical repair device of this invention has functional advantages over the implant device described in European patent (hereafter EP) Application No. 122,744. For example, this invention can utilize absorbable fibers in the axial (lengthwise) direction. The majority of absorbable fibers in the axial direction enhances or essentially guarantees the transfer of the connective tissue stress from the device to the ingrowing collagen fibers. In summary, with the majority of fibers being in the axial direction and with these fibers being at least about 80% absorbable fibers, there appears to be more tissue ingrowth and better oriented collagen fibers.
This invention is useful as a temporary or augmentation device. In this utility, it seems to match as closely as possible the biological properties of a connective tissue until ingrown collagen fibers can replace the majority of fibers (preferably having an absorbable component comprising at least about 80 percent) in the axial direction. The advantage of this invention, e.g. over the implant device disclosed in EP Application No. 122,744, is that it appears to provide a surgical repair device (specifically for connective tissue, and more specifically for ligament or tendon repair) that will have the correct stress related properties to act as a connective tissue (until living tissue can replace the device). This is accomplished by the ingrown collagen fibers replacing the absorbable fibers in the axial direction. The use of nonabsorbable fibers is as a support or backbone for the absorbable fibers.
This invention has superior and unexpected structural properties over those disclosed in the prior art, specifically EP Application No. 122,744. For example, the majority of the fibers in this invention, that is 50 percent or more, are in the axial (lengthwise) direction. Preferably, 80 to 95 percent are in the axial direction. This approximately twofold increase of fibers in the axial (lengthwise) direction (over the axial direction fibers in EP Application No. 122,744) is at least one of if not the primary reason for obtaining the functional advantages discussed above.
The surgical repair device of this invention has other advantages over the prior art. For example, the thickness of the device is smaller than the known prior art devices. This is because the majority of the fibers are in the axial direction. The smaller thickness allows this device to be useful in more constricted connective tissue repair procedures. Also, as a general statement, the smaller the thickness or width of the repair device, the greater is its utility as a temporary or augmentation device because tissue ingrowth is facilitated. Conversely, the larger the thickness or width of the device, the more it is used as replacement (that is, as a permanent implant) rather than a temporary device.
It is, therefore, the object of this invention to provide sterile, surgically implantable devices, means for surgical placement/attachment, and fabrication processes that are uniquely suited for providing the most advantageous connective tissue (i.e. ligament, tendon, etc.) repair. These implants resolve the apparent disadvantages of the devices described above by: (1) providing adequate strength and stiffness immediately post-operatively to minimize or eliminate the need for immobilization; (2) facilitating the ingrowth of vascularized cellular tissue by reason of the open flat tape configuration; (3) supporting the proper orientation of collagen fibers formed within and around the implant through the predominantly axial alignment of the component yarns and the gradual transfer of applied loads from the biodegradable yarns to the newly formed tissue; (4) providing a longer lasting bioadsorbable material to permit adequate time for new tissue ingrowth or revascularization of autogenous tissue grafts or allografts; (5) providing a compliant, elastic, permanent component to protect tissues from over-load, without stress-shielding, for a longer term than provided by the bioabsorbable materials, in those applications (i.e. some intraarticular ligament reconstructions) where healing occurs more slowly; and (6) avoiding the use of materials which fragment and pose risks of migration to adjacent tissues.
The object of this invention comprises bioabsorbable or combined bioabsorbable/bicompatible polymers fabricated into an elongated textile structure having means for surgical placement/attachment at one or both ends for the purpose of repair, augmentation or replacement of damaged connective tissues, such as ligaments and tendons.
SUMMARY OF THE INVENTION
A surgical repair device having a length to width ratio of greater than one has been invented. The device comprises a plurality of fibers. The majority of the fibers are in a direction essentially parallel to the device length.
The device has an absorbable component comprising from about 10 to 100 percent of polymer having a glycolic or lactic acid ester linkage. The remainder of the device, if any, has a nonabsorbable component.
In one embodiment of the device, the absorbable polymer is a copolymer having a glycolic acid ester linkage. In a specific embodiment, the copolymer comprises glycolic acid ester and trimethylene carbonate linkages.
A connective tissue repair device having a length to width ratio of greater than one has also been invented. The device comprises a plurality of fibers. The majority of the fibers are in a direction essentially parallel to the device length. The device has an absorbable component comprising from about 10 to 100 percent of a copolymer. The copolymer has glycolic acid ester and up to about 50 percent by weight of trimethylene carbonate linkages. The remainder of the device, if any, has a nonabsorbable component.
Embodiments of the repair device include a knitted, woven, braided and flat braided device. In one embodiment, the longitudinally oriented majority of the fibers comprises about 80 to 95 percent. In a specific embodiment, the longitudinally oriented majority of the fibers comprises about 90 percent.
In another embodiment, the device has an absorbable component comprising at least about 80 percent. In a specific embodiment, the device has a nonabsorbable component selected from the group consisting of a poly(C 2 -C 10 alkylene terephthalate), poly(C 2 -C 6 alkylene), polyamide polyurethane and polyether-ester block copolymer. In a more specific embodiment, the device consists of poly(ethylene terephthalate) or poly(butylene terephthalate) as the poly(C 2 -C 10 alkylene terephthalate), and a polybutester as the polyether-ester block copolymer. In a most specific embodiment, the device consists of Hytrel™ as the polybutester.
A polybutester can be defined as a polytetramethylene glycol, polymer with terephthalic acid and 1,4-butanediol. See, e.g., the definition of polybutester in USAN and the USP dictionary of drug names, U.S. Pharmacopeial Convention, Inc., MD 20852 U.S.A., 1985.
Hytrel™ is a trademark of E. I. du Pont de Nemours & Co., Wilmington, Del. U.S.A. for a class of polymers having the following generic formula: ##STR1##
The values for a, x and y are known from the prior art, e.g. as disclosed in "Thermoplastic Copolyester Elastomers: New Polymers For Specific End-Use Applications", M. Brown, Rubber Industry 9 102-106 (1978), and the references (footnote numbers 1b, 1c, 1d, 2 and 3) cited therein; Encyclopedia of Polymer Science and Technology, Supplement, 2 485-510, see particularly pages 486 to 493, Interscience N.Y. 1977; and U.S. Pat. No. 4,314,561 issued Feb. 9, 1982. All of this prior art is incorporated herein by reference. A specific embodiment of Hytrel® which is useful in this invention is a grade of Hytrel® having a 72 durometer D. hardness. The polymer in the NOVAFIL® (American Cyanamid Company, New Jersey, U.S.A.) surgical suture contains Hytrel®.
A flat braided ligament or tendon implant device having a length to width ratio of greater than one has been invented. The device comprises a plurality of fibers. The majority of the fibers are in a direction essentially parallel to the implant length. The braid has about 5 to 100 carrier and up to about 50 warp yarns.
The implant has an absorbable component comprising from about 10 to 100 percent of a copolymer. The copolymer has glycolic acid ester and from about 20 to 40 percent by weight of trimethylene carbonate linkages. The remainder of the implant, if any, has a nonabsorbable component.
In one embodiment of the implant, the braid has about 13 carrier and about 6 warp yarns. In a specific embodiment, the implant consists of about 100 percent of the absorbable component. In a more specific embodiment, the carrier yarns consist of about 100 percent of the absorbable component and the warp yarns comprise about 8 percent of the absorbable component. In a most specific embodiment, the nonabsorbable component in the warp yarns is selected from the group consisting of a poly(ethylene terephthalate) and polyether-ester block copolymer.
In other embodiments of the implant, the yarns are texturized or heat treated. In a further embodiment of the implant, the braid is heat treated.
The bioabsorbable filaments may be comprised of man-made polymers including glycolide-trimethylene carbonate (GTMC), polyglycolic acid, polydioxanone, poly(L-Lactic) acid, poly(DL-Lactic) acid and copolymers or physical combinations of the components of these polymers. Natural bioabsorbable polymers such as regenerated collagen or surgical gut may also be used. The biocompatible (nonabsorbable) components include poly(ethylene terephthalate) (PET), poly(butylene terephthalate) (PBT), polyether-ester multi-block copolymers, polypropylene, high strength/modulus polyethylene, polyamide (including polyaramid), or polyether type polyurethanes. Once spun into filaments, the properties of the above materials may be improved for this application by various temperature/time/stress treatments.
The device shall be braided, woven or knitted so that the structure has the desired strength and stiffness in the primary (axial) loading direction. It also has adequate interfibrillar space and minimized thickness to promote the ingrowth of tissue. The end(s) of the device may be compressed inside biocompatible metal sleeve(s) to which swivel end-caps(s) and surgical needle(s) are attached in such a way as to permit rotation of the needle(s) about the longitudinal axis of the device.
In use, an appropriate number of plies of the device are implanted to match the biomechanical properties of the tissue being repaired. This permits an early return to normal function post-operatively. As the ligament or tendon begins to heal, the implant continues to bear any applied loads and tissue ingrowth commences. The mechanical properties of the bioabsorbable component(s) of the implant then slowly decay to permit a gradual transfer of loads to the ingrown fibrous tissue, stimulating it to orient along the loading direction. Additional ingrowth continues into the space provided by the absorbed components of the implant. This process continues until the bioabsorbable component(s) are completely absorbed and only the newly formed tissue remains, or the bicompatible (nonabsorbable) component(s) are left in situ to provide long-term augmentation of the newly formed tissue.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic view of the device described as the preferred embodiment, except that two different possible ends are shown.
FIG. 2 is an enlarged view of the flat surface of the preferred embodiment showing the braided construction in greater detail.
FIG. 3 is an anterior view of a knee showing the device as positioned for repair of the excised patellar ligament in animal (canine) studies.
FIG. 4 is an anterior view of a knee showing the device as positioned for augmentation of the medial third of the patellar ligament in an Anterior Cruciate Ligament reconstruction.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In preferred embodiments the elongated textile structure 1 of the implant comprises a flat braid having primarily axial (quoit) yarns 2 of an absorbable polymer such as GTMC. The number and denier of quoit and sleeve yarns are varied to provide devices having a range of properties that are biochemically compatible with any likely implant site. Swivel end cap(s) 3 and surgical needle(s) 4 may be attached at the end(s) of the device to facilitate placement and attachment.
The procedures described below are followed when preparing flat braids to be used as artificial ligaments/tendons starting from the appropriate yarns. To begin, the proper denier yarns for the specific braid construction are required. This example describes a typical construction designed to fit a particular animal model--repair/replacement of the canine patellar ligament (FIG. 3). An application that had a tensile strength/stiffness requirement three times higher than that described in the example would require three times as much yarn. This could be accomplished by simply tripling the final total braid denier, either by increasing the yarn denier or increasing the number of sleeve and quoit (stuffer yarns) or both.
To produce a braid for canine patellar ligament repair (FIG. 3), a final braid denier between 13,000 and 24,000 is targeted. In the preferred construction, approximately 90% of the fiber is contained in the parallel quoit or warp yarns 2.
The sleeve yarns 5, which consist completely of absorbable material, are generally about 130 denier. On transfer they are given a nominal 1.4 turn per inch (TPI) `Z` or `S` twist before further processing. This facilitates handling and minimizes fiber breakage.
The quoit (stuffer or warp) yarns can be 100% absorbable or they may contain a nonabsorbable component. They are much heavier than the sleeve, generally ranging from 2100 to 2700 denier. This necessitates two passes on a six position ply twister. A 130 denier yarn would normally be 5-plied 2.8 TPI `S` or `Z`, then 4 ends of the 5-ply yarn would be twisted 1.4 TPI in the reverse direction. This would result in a final quoit yarn denier of 2600, mechanically balanced from the reverse twist operation (no tendency to twist or unravel).
Nonabsorbable components 6, if included, are blended into the quoit yarns during the 1st ply twisting operation. For instance, a MAXON™/NOVAFIL® (American Cyanamid Co., NJ 07470 U.S.A.) bicomponent yarn consisting of 18-22% nonabsorbable fiber would be made by running 1 yarn of 130 denier NOVAFIL® with 4 yarns of 130 denier MAXON™ in the 5-ply operation. The preparation and polymeric composition of MAXON® is disclosed in U.S. Pat. Nos. 4,429,080; 4,300,565 and 4,243,775; the preparation and polymeric composition of NOVAFIL® is disclosed in U.S. Pat. Nos. 4,314,561; 4,246,904; and 4,224,946. All of these patents are incorporated herein by reference. The exact proportion of NOVAFIL® is determined by the yarn deniers involved and the proportion of quoit yarns in the braid construction.
An important processing step for some absorbable yarns is post treatment (a vacuum annealing step which upgrades the implant tensile values). Generally speaking, for a construction that is to be 100% absorbable, the yarns are post treated after ply twisting; for an absorbable/nonabsorbable bicomponent construction, the absorbable yarns are post treated prior to ply twisting. There is another option and that is to post treat the final braid, providing it does not have a deleterious effect on a nonabsorbable component.
After ply twisting and post treatment, the yarns are ready for braiding. The best results to date are obtained with a construction that is made on a 13 carrier flat braider, which has 6 quoit yarn feeds. About 90% of the construction is composed of the heavy parallel quoit yarns held loosely together by the sleeve yarns at 12.3 picks (yarn cross-over points) to the inch.
After braiding, the ligament is ready for further processing. It is cut to length and sleeved on both ends with a 1/4" aluminum or silver sleeve. A stainless steel over cap 3 with a small metal swivel pin 7 is then attached.
The end capped ligaments are now ultrasonically washed in xylol to remove any residual finishing oils (6 min residence in each of 4 baths). After the implants are air dried, appropriate needles 4 are attached to the metal pins to allow the implant to swivel in use.
They are then packaged in preformed plastic trays with a lid and in open aluminum foil laminate envelopes. They are sterilized in an Ethylene Oxide cycle which includes an elevated temperature vacuum drying step. The foil laminate envelopes containing the dry ligaments are then heat-sealed in an asceptic glove box hood fed by dry air. Any interim storage needed between vacuum drying and heat sealing is carried out in an asceptic sealed box fed, again, by dry air.
Devices, as described above, may be surgically implanted to bridge a defect in a ligament, as a replacement for an excised damaged ligament (FIG. 3) or as an augmentation (FIG. 4) for autogenous tissue graft (or allograft) ligament reconstruction. In those surgical procedures requiring passage through and/or attachment to soft tissue 9, implants having the end-cap 3 and swivel needle(s) 4 at the end(s) would be used. For those applications in which the implant only needs to be passed through an open joint space 10 or through pre-drilled tunnels in bone 11, the swivel needles would not be required. Implants provided for such procedures may instead have either: (a) melt-fused ends to prevent fraying, or (b) ends stiffened by surrounding tubes 8 that are melt-fused or heat-shrunk onto the material of the device itself.
The invention can be described by the following examples.
EXAMPLE 1
The implant consists of 100% MAXON™ yarns in a 13 carrier flat braid construction. It was made from 100 denier/8 fil MAXON™ yarns that were post treated prior to twisting. Both sleeve and quoit yarns were twisted at 10 TPI to retain yarn integrity. The sleeve yarns consisted of 13 carriers holding 200 denier yarns made by 2-plying the 100 denier yarns. The 6 quoit or stuffer yarns were made by a double pass (6 yarns over 6 yarns) on the ply twister to form a 3600 denier yarn. The final braid denier was 24,200 with 89.3% of the fibers contained in the quoits. Picks/inch were calculated at 12.3.
The braid was then forwarded to an outside vendor to be cut to length and end capped. On return, the implants were washed ultrasonically in xylol, dried, needled and packaged. In this instance, packaging consisted of a 1 mil aluminum foil inner envelope, dry sealed after ETO sterilization and vacuum drying. Inner envelopes were then overwrapped in a TYVEK™ (E. I. du Pont de Nemours & Co., DE 19898 U.S.A.) package prior to a 2nd ETO sterilization cycle.
Straight pull tensile strengths averaged at 203 lbs equivalent to 3.8 grams/denier with an extension to break of 33.4%. Hydrolytic strength data indicated that the device was viable and samples were implanted in 10 month or older beagle dogs replacing the canine patellar ligament. Sacrifices occurred at 2, 4 and 6 months. Histological examination indicated 50-90% infiltration of the device by cellular tissue and some collagen fiber at 2 months, and well organized collagen replacing the absorbed MAXON™ at 6 months. Some displacement of the patella was evident at 2 and 4 months, but 6 month X-ray data approximated the non-operated controls. `Neo-ligament` cross sectional area at the 2 month interval was approximately 2 to 3 times that seen on the non-operated controls. The size of the tissue mass gradually decreased at subsequent post-operative evaluation periods. Final tensile strengths of excised ligaments ranged from approximately 180 lb. at 2 months, to approximately 250 lb. at 4 and 6 months, with extensions at break of 7.9 to 9.2 mm which are in the range of the unoperated controls.
EXAMPLE 2
This implant also consists of 100% MAXON™ in a flat braid construction. However, the source yarns were heat stretched at 32% prior to braiding and post treated after braiding. The construction itself consisted of 13-124d sleeve yarns twisted to 2.2 TPI `S` and 6-2232d quoit yarns ply twisted as follows: first 3 yarns at 2.2 TPI `Z` which were then reverse twisted--6 yarns at 1.1 TPI `S`. The total final denier was 15,000 with 89.3% comprised of quoit yarns. This construction also had 12.3 Picks/inch.
This braid had a 148 lb breaking strength (equivalent to 3.94 grams/denier) with an extension at break of 26.2%. Hydrolytic data indicated the material was viable as an implant. Sterile devices of this type were prepared as in Example 1.
EXAMPLE 3
This implant was a MAXON™/DACRON® bicomponent in an approximately 80/20 blend. DACRON® is a trademark of E. I. du Pont de Nemours & Co., Del. 19898 U.S.A., for a synthetic poly(ethylene terephthalate) fiber. Both components had been heat stretched at 18.5-20% prior to ply twisting. To make the quoit yarns, four yarns of 120d MAXON™ were twisted at 1.4 TPI `Z` and then combined with 1 yarn of 127d DACRON® (also twisted at 1.4 TPI `Z`) in a ply twisting operation at 2.8 TPI `S`. Four of these bicomponent yarns were then reverse twisted at 1.4 TPI `Z` for a total denier of 2428. The sleeve yarn was simply 120d MAXON™ twisted to 9.1 TPI `Z`.
The flat braid was made on a 13 carrier machine with 6 quoit yarns at a 12.3 pick. Total denier was 16,128 with 90.3% of the total construction combined in the quoits. 18.9% of the total construction consisted of the nonabsorbable (DACRON®) component.
This sample broke at 140 lbs (equivalent to 3.94 grams/denier) with a 24.2% breaking elongation. Hydrolytic data indicated the sample was viable. Samples were prepared as in Example 1, and implanted in 10 month or older beagle dogs replacing the canine patellar ligament. Histological evaluation of the repaired ligament at 2 months indicated the ingrowth of cellular tissue to be localized near the implant periphery. At subsequent post-operative intervals, collagen was observed as an oriented fibrous sheath surrounding the remaining Dacron® yarns with minimal tissue infiltration or vascularization noted. However, the cross-sectional area, as well as the length of the neo-ligaments were substantially equivalent to those obtained with the device of Example 1. Average tensile strengths of the repaired ligaments at the 2, 4, and 6 month post-operative evaluation periods also ranged from approximately 180 lb. to 250 lb. The extensions at break for ligaments repaired with these particular devices were between 8 and 16 mm; generally greater than the unoperated controls.
EXAMPLE 4
This construction utilized heat stretched MAXON™ combined with NOVAFIL® in an 80/20 combination. The sleeve yarn was simply 120d MAXON™ twisted at 9.1 TPI `Z`. The quoit yarns consisted of 2 yarns of 68d NOVAFIL® that had previously been ply twisted at 1.4 TPI `Z` combined with 4 yarns of MAXON™ twisted to 1.1 TPI `Z` prior to heat stretching at 20%. These yarns were ply twisted at 2.8 TPI `S`. Four of these bicomponent yarns (of about 616 denier) were then reverse twisted at 1.4 TPI `Z` to give a quoit yarn of 2464 denier.
These yarns were braided on a 13 carrier flat braider with 6 quoit ends at 12.3 picks/inch. Final braid denier was 16,344, of which 90.5% was contained in the quoits. Approximately 22.1% of the total construction was the nonabsorbable component-NOVAFIL®.
The resulting ligament broke at 155 lbs (equivalent to 4.31 grams/denier). The extension at break was 27.4%. Hydrolytic tests indicated that this design was a viable one. After further processing, as in Example 1, devices of this type were implanted in 10 month or older beagle dogs replacing the patellar ligament. Compared to the repairs made with the devices described in Examples 1 and 3, these implants appeared to yield the best histological results. Approximately 70-90% of each of the implants had been infiltrated with well organized, vascularized, cellular tissue and some collagen fibers within 2 months. Results improved with time, so that at six months the non-absorbable NOVAFIL® yarns served as a scaffold that was completely infiltrated with well vascularized, axially oriented collagen fibers. The `neo-ligament` cross-sectional area and length followed the same trends as in Examples 1 and 3. Tensile strengths gradually increased from approximately 180 lb. at 2 months to about 250 lb. at 6 months; well within the range of unoperated control strengths which averaged 220 lb. The extension-at-break remained fairly constant at 11-12 mm which, while generally greater than the unoperated controls was intermediate to the results noted in Examples 1 and 3.
Examples 5 to 10 were part of an experimental study designed to determine the effect of heat stretching and post treatment on MAXON™. The net conclusion was that post treatment served to upgrade implant properties; heat stretching by itself or in combination with post treatment did not markedly improve MAXON™ implant properties after sterilization.
EXAMPLE 5
This construction is also 100% MAXON™ in a flat braid construction. The yarns were not heat stretched before braiding. The sleeve yarns consisted of 130d MAXON™ twisted to 1.4 TPI `S`. The quoit consisted of 5 yarns of 130d MAXON™ twisted to 2.8 TPI `Z`. Four yarns of this 5 ply construction were then twisted to 1.4 TPI `S` for a total denier of 2600.
The above yarns were then braided on a 13 carrier braider with 6 quoit ends set at a 12.3 pick. The final construction came to 17,694 denier, of which 90.2% were quoit ends.
After sterilization this construction measured 19,134 denier. It had a 138 lb breaking strength (equivalent to 3.27 grams/denier) and an extension at break of 54.2%.
EXAMPLE 6
The same as Example 5 except that the yarns used were post treated before braiding.
The final denier was 17,550 which changed to 18,288 after sterilization. The sterile devices had a breaking strength of 126 lbs (3.13 grams/denier) with an extension at break of 38.1%.
EXAMPLE 7
The same as Example 5 except that the braid itself was post treated.
The final denier was 17,811 which changed to 18,414 after sterilization. Strength to break was 145 lbs (3.57 grams/denier) with an extension at break of 39.3%.
EXAMPLE 8
The same as Example 5 except that the ply twisted yarn was heat stretched at 26% before braiding. Material was not post treated either as a yarn or braid.
The final denier was 16,497 which changed to 19,332 after sterilization. Strength to break was 121 lbs (2.84 grams/denier) with an extension at break of 44%.
EXAMPLE 9
Same as Example 8 except that this yarn was post treated after heat stretching.
The final denier was 15,786 after braiding. On sterilization this changed to 18,034. The strength to break of the sterile devices was 135 lbs (3.41 grams/denier) with an extension at break of 34.2%.
EXAMPLE 10
Same as Example 8 except that the braid itself was post treated.
The final denier was 16,362 after post treating; 17,392 after sterilization. The strength to break of the sterile implants was 150 lbs (3.90 grams/denier) with an extension at break of 34.6%.
EXAMPLE 11
This embodiment consisted of 100% MAXON™ in a flat braid construction. It differs from constructions described in previous examples in that it was airjet texturized prior to the initial twisting steps. The sleeve yarn consisted of 149d texturized MAXON™. This was made by overfeeding 2 yarns of 66 denier MAXON™ into the airjet chamber-one by 15% and the other by 8%. This material was then twisted to 1.4 TPI `Z`. The quoit yarn started with 219 denier texturized MAXON™. This was made by overfeeding 1 end of 66d MAXON™ at 15% into the airjet along with 1 end of 130d MAXON™ at 8%. The 219 denier yarns were then 3-plied at 2.8 TPI `S`. Four yarns of the 3-ply material were then reverse twisted at 1.4 TPI `Z` to give a final denier of 2523.
This material was braided on a 13 carrier flat machine at 12.3 picks per inch. Its final denier measured 17,693 with 88.7% of the construction in the quoits.
The straight pull to break averaged 130 lbs (3.3 gms per denier) with an extension at break of 26.7%. As expected, its surface appearance resembled that made of yarns spun from a natural, staple fiber such as cotton or wool. Optically, the braid could be characterized as having a loose, single fil looped appearance. Subsequent processing of the braid is as described above under the heading Description of the Preferred Embodiment`.
EXAMPLE 12
This design is identical to Example 11 except that in the initial 3-plying of the quoit yarns one end of a 245 denier MAXON™/NOVAFIL® texturized bicomponent yarn was substituted for one of 219 denier texturized MAXON™ yarns. This MAXON™/NOVAFIL® bicomponent was made by overfeeding a 66d MAXON™ yarn at 55% and two 69d NOVAFIL® yarns at 11% into the airjet chamber. The denier of the 12 ply quoit yarn was measured to be 2667d.
This material was braided on a 13 carrier flat machine at a 12.3 pick. Its final denier was 18,467 of which 89.2% was quoit yarn and 19.1% was the nonabsorbable NOVAFIL® component.
The final non-sterile ligament had a breaking strength of 122 lbs (3.00 grams per denier) and an extension at break of 25.9%. Hydrolytic data indicates that this will make a viable product with a residual strength of 29.5 lbs.
Subsequent processing of the braid is as described above under the heading `Description of the Preferred Embodiment`.
EXAMPLE 13
This implant design is identical to Example 11 except that in the initial 3 plying of the quoit yarns one end of a 226 denier MAXON™/Heat Stretched Texturized DACRON® bicomponent yarn was substituted for one of the 219 denier MAXON™ yarns. This MAXON™/Heat Stretched DACRON® bicomponent was made by overfeeding a 66 denier MAXON™ yarn at 55% and a 127 denier heat stretched DACRON® yarn at 11% into the airjet chamber. The denier of the 12 ply quoit yarn measured 2613.
This material was braided on a 13 carrier flat machine at a 12.3 Pick. Its final non-sterile denier was 18,054, of which 89.0% was quoit yarn and 20.7% was the nonabsorbable heat stretched DACRON® component.
The final non-sterile ligament had a breaking strength of 97 lbs (2.43 grams per denier) and an extension at break of 21.7%. Hydrolytic data indicated it would remain unchanged in strength for 14 days and would have a residual strength of 34.7 lbs.
Subsequent processing of the braid is as described above under the heading `Description of the Preferred Embodiment`.
EXAMPLE 14
This construction consists of 100% MAXON™ in a flat braid construction. It differs from previous constructions in that it is braided on a 21 carrier machine.
The sleeve yarn consists of 66 denier MAXON™ yarn twisted to 1.4 TPI `Z`. The 130 denier quoit yarns are first 2-plied at 2.8 TPI `S`--then 5 yarns of this 2-ply construction are reverse twisted at 1.4 TPI `Z`. The final denier of the 10 ply quoit yarn is 1300.
The above yarns are then braided on a 21 carrier machine with 10 quoit yarns set at a 12 picks/inch. The final construction measures 16,986 denier, of which 91.8% is quoit yarn.
Samples are expected to have a non-sterile breaking strength of 124 lbs (equivalent to 3.31 grams per denier) with an extension at break of 35.2%.
EXAMPLE 15
This construction consists of 100% MAXON™ in a flat braid construction. It differs from previous constructions in that it is braided on a 15 carrier machine.
The sleeve yarn consists of 98 denier MAXON™ twisted to 1.4 TPI `Z`. The 130 denier quoit yarns are 5-plied at the same level of twist to give a total denier of 650. All yarns are post treated after plying.
The above yarns are braided on a 45 carrier machine. Only 15 out of 45 available carriers are used for the sleeve yarns. All of the available 22 quoit positions are used. The braider is set for a 4.1 pick. The final construction measures 15,770 denier, of which 90.7% is parallel quoit yarn.
Straight pull tensile strength is expected to average approximately 168 lbs (4.83 grams/denier) with a 37.2% elongation at break.
EXAMPLE 16
This implant design is similar to Example 15 except that 1 yarn of heat stretched DACRON™ is substituted in ply twisting the quoit yarns. Also, all MAXON™ yarns are post treated prior to twisting.
The final braid denier is 15,700, of which 90.7% is parallel quoit yarn. Approximately 18.1% of the total construction is the nonabsorbable DACRON® component.
Straight pull tensile strength is expected to be approximately 127 lbs (3.67 grams/denier) with a breaking elongation of 29.3%. Hydrolytic data from similar constructions indicate that this design would make a viable product with a residual strength of 29 lbs due to the nonabsorbable component.
EXAMPLE 17
This design consists of 100% MAXON™ in a flat braid construction. Although braided on a 45 carrier machine, it differs from Sample 15 in that it is 3.3 times heavier.
The sleeve yarns consist of 130 denier MAXON™ twisted to 1.4 TPI `Z`. The 130 denier quoit yarns were first 4-plied to 2.8 TPI `Z`, then four 4-ply yarns are reverse plied to 1.4 TPI `S` to give a final quoit yarn denier of 2080. All yarns are post treated after twisting.
The above yarns are then braided on a 45 carrier machine using all available carriers for the sleeve and all of the available 22 quoit yard positions. The braider is set for a 12.3 pick. The final construction measures 51,610 deniers, of which 88.7% is parallel quoit yarn.
Straight pull tensile strength is expected to average 525 lbs (4.61 grams/denier) with a breaking elongation of 31.6%.
Although the following examples, and variations thereof, may be suitable for some soft tissue orthopedic (i.e. tendon) repair/reconstruction applications, they have been found to be inappropriate as ligament implants and therefore not part of this invention. They are disclosed for their comparative value to Examples 1-to-17, and as a contribution to the state of the art.
COMPARATIVE EXAMPLE A
This construction is a round bicomponent braid consisting of three braided elements.
a. A subcore which is a blend of 20/80 PGA/Heat Stretched DACRON®. This subcore was made on an 8 carrier braider set at 5 picks/inch with each carrier containing a 1060 denier bicomponent yarn. The 1060 denier yarn was made by ply twisting 4 yarns of 210 denier heat stretched DACRON® with 2 yarns of 110 denier DEXON® (American Cyanamid Co., NJ 07470, U.S.A.) at a low nominal level of twist. The preparation and polymeric composition of DEXON® is disclosed in U.S. Pat. No. 3,297,033, which is incorporated herein by reference.
b. A core is also a blend of 20/80 PGA/Heat Stretched DACRON®. This was made by braiding on a 12 carrier braider set at 5 picks/inch using the 8 carrier braid described above as a core. Each of the 12 carriers contained a 1270 denier bicomponent yarn which was made by ply twisting 5 yarns of 210 denier Heat Stretched DACRON® with 2 yarns of 110 denier DEXON® at a low level of twist.
c. The final sleeve was a blend of 60/40 PGA/Heat Stretched DACRON®. This was made by braiding on a 16 carrier braider set at 15 picks per inch using the 12 carrier braid described above as a core. Each of the 16 carriers contained a 1510 denier bicomponent yarn which was made by ply twisting 3 yarns of 210 denier Heat Stretched DACRON® with 8 yarns of 110 denier DEXON® at a low level of twist.
All of the above yarns were post treated after ply twisting. This braid broke at 430 lbs straight pull (equivalent to 4.07 grams/denier) with an 18.8% extension at break. Braid denier was calculated to be 47,900.
Intramuscular and subcutaneous implants in canines exhibited little, if any, tissue ingrowth. Braids were encapsulated by unorganized collagen. This lack of vascularized cellular tissue and oriented collagen infiltration into the implant is considered undesirable for ligament repair or reconstruction. It is most probably a combined effect of: (1) the relatively short strength retention period of the PGA (i.e. 28 days); and (2) the tight round construction which minimizes implant-tissue interface area.
COMPARATIVE EXAMPLE B
This construction was basically the same as that in Comparative Example A except that the final sleeve was a 50/50 PGA/Heat Stretched DACRON® bicomponent yarn in a finer (more dispersed) blend. This was made on a 16 carrier braider set at 15 picks/inch using the 12 carrier braid described in Example A as a core. Each carrier contained a 1320 denier bicomponent yarn made by first ply twisting 1 yarn of 110 denier Heat Stretched DACRON® with 1 yarn of 110 denier DEXON®. Six of the 2-ply bicomponent yarns were then twisted to make the final 12-ply yarn. Twist levels were of a low order of magnitude.
The final braid denier was calculated to be 44.8K. The breaking strength measured 385 lbs (equivalent to 3.89 grams/denier) with a breaking elongation of 16.8%. Animal implant data were similar to Example A.
COMPARATIVE EXAMPLE C
This construction was, again, basically the same as in Comparative Example A except that the final sleeve had a coarser (less dispersed) configuration. It consisted of alternating a 1650 denier DACRON® (Heat Stretched) yarn with 1650 denier DEXON® yarn on each of the 16 carriers.
The final breaking strength was 429 lbs (equivalent to 3.88 grams/denier). The elongation at break was 17.8%. The final denier was calculated to be 50,100. Animal implant results were similar to Example A.
COMPARATIVE EXAMPLE D
This implant design was 100% DEXON® PGA in a round braid configuration and it consisted of three braided elements:
a. The subcore was made on an 8 carrier braider set at 5 picks/inch. Only 4 out of the eight sleeve carriers were used. The 440 denier yarn was made by plying four 110 denier yarns at a low number of twists per inch.
b. The core was made on an eight carrier machine also set at 5 picks/inch with all eight carriers containing a 550 denier yarn. The yarn was made by plying five 110 denier yarns at a low level of twist. The 4 carrier braid described above was used as a core.
c. The sleeve was made on a twelve carrier braider set at 15 picks/inch with all 12 carriers containing a 660 denier yarn. The yarn was made by plying six 110 denier yarns at a low level of twist. The eight carrier braid described above was used as a core.
The final denier was calculated to be 14,100. Tensile strength was measured to be 134 lbs (equivalent to 4.32 grams/denier). The elongation at break was 33.4%.
IMPLANT RESULTS
This material was implanted as a replacement for the resected patellar ligament of 10 month or older beagle dogs. At 1 and 2 months there was no histological evidence of tissue ingrowth. Braids were encapsulated by unorganized collagen and were structurally weak. This construction was abandoned since there was little hope for its use in ligament repair or replacement applications where ingrowth is desired.
COMPARATIVE EXAMPLE E
This implant design was 100% DEXON® (PGA) in a flat braid configuration and consisted of heavy denier quoit or warp yarns held together by light denier sleeve yarns:
a. Each quoit yarn contained 2214 denier DEXON® which was made by ply twisting three--123 denier yarns to give 369 denier yarn and then ply twisting six of these 369 denier yarns at 1.5 TPI `S`.
b. The sleeve yarn contained 110 denier DEXON® yarns which were twisted to 10 TPI `S`.
c. The braid was made on a thirteen carrier braider--each carrier containing 110 denier sleeve yarn which was braided about the 2214 denier warp yarns fed through all six available quoit positions. The total pick count was estimated at 10 per inch.
d. This construction was washed and post treated as a braid.
The total braid denier was approximately 15,100. Tensile strength measured 208 lbs. with a 22.3% elongation-to-break.
Devices of this design were implanted as replacements for the resected patellar ligament of 10 month or older beagle dogs in a comparative study with devices of Example 1. Histological evaluation at 1 and 2 months post-operatively revealed no significant tissue ingrowth or organization within the PGA implant. This lack of ligament repair was attributed to the relatively shorter in-vivo property retention period of the PGA material.
COMPARATIVE EXAMPLE F
This implant design was 100% DEXON® (PGA) in a flat braid configuration and again consisted of heavy denier quoit or warp yarns held together by light denier sleeve yarns. However, all the yarns were post treated; then air jet texturized prior to twisting and braiding.
a. The quoit (warp) yarn consisted of a 6 ply construction using 357 denier texturized DEXON® yarn to give a total 2142 denier yarn. This 357 denier yarn was made by entangling 3 ends of 110 denier DEXON® yarn--2 yarns with a 24% overfeed and one with a 6% overfeed.
b. The sleeve yarn was made similarly except it was a 152 denier, texturized DEXON® yarn. This was made by entangling 2 yarns of 62 denier DEXON®--one yarn with a 24% overfeed and the other with an 11% overfeed.
c. The braid was made on a thirteen carrier braider, each carrier containing the 152 denier yarn described in section b above. These sleeve yarns were braided about the 2142 denier warp yarns fed through all six available quoit positions. The total pick count was estimated at 12.3 per inch.
The total braid denier was 14,800. Tensile strength measured 152 lbs. with a 23.2% elongation-to-break.
Devices of this construction were evaluated in-vivo as described in the previous example. Upon sacrifice at 2 months, these implants were found to have better tissue ingrowth/organization than the non-texturized PGA devices of the previous example. However, the results achieved with implants made using the longer lasting GTMC yarns were consistently, significantly improved over those obtained with the devices of these comparative examples.
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A surgical repair device having a length to width ratio of greater than one is disclosed. The device has an absorbable component consisting essentially of a first plurality of fibers. Each fiber of the first plurality of fibers is prepared from poly(butylene terephthalate) or a polymer having a glycolic or lactic acid ester linkage. The deivce also has a nonabsorbable component consisting of a second plurality of fibers. Each fiber of the second plurality of fibers is prepared from a polyether-ester block copolymer. The device comprises about ten percent of the first plurality of fibers and about ninety percent of the second plurality of fibers. The majority of the first and of the second plurality of fibers is essentially in the lengthwise direction of the device. The device can be knitted or woven. In one embodiment, the device is a connective tissue repair device.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the art of injection molding plastic products and particularly to the heating and cooling the skin of the mold cavity to achieve an improved surface finish.
2. Description of the Prior Art
In the manufacture of molded plastic parts many applications require that the part have a shiney or glossy surface when the part comes out of the mold. In the injection molding of solid parts this shiney surface is achieved. However, in the manufacture of foam molded parts, the surface finish is usually a mottled finish with swirls because the gas used or generated in the process of foam molding escapes to the surface of the part in the mold until the surface starts to solidify. As the surface solidifies, gas is trapped inside the part and the cellular inner structure develops. During the cooling cycle, while gas is still escaping to the surface, the mottled finish and swirls occur. This dull finish is objectionable because the part manufactured by this foam molding process now requires a secondary operation of finishing the parts since the mottled appearance of the original finish is not commercially acceptable.
A method of eliminating the mottled appearance is to retain the heat above the deformation temperature of the resin at the mold surfaces of the part until the cavity is full. This is a difficult and essentially an impractical approach after the part has been molded. Other methods are discussed in an article in Plastic Technology, Vol. 22, No. 5, May, 1976, pages 33-36, to heat up the mold itself both before and during the molding cycle. This article details lengthening the mold fill time to get a no slip flow condition at the surface of the mold during filling. Another is to increase the melt temperature to again reduce the slip/no slip condition and the third is to increase the mold temperature which causes a thin surface layer of the injected melt to retain heat which reduces the slip/no slip condition.
A process of heating the mold is described in U.S. Pat. No. 3,044,118 which heats up the whole mold above the melting temperature of the plastic, and then cools the mold down after the injection cycle using carbon dioxide gas. This method is very slow and time consuming depending on the particular part being molded and the structural sections within the part. Also the mold is subjected to extraordinary stress during this heating and cooling cycle and such stress could crack or weaken the mold which limits its useful life. Other solutions are to use low mass molds and incorporate low-mass-interior conducting surfaces, backed-up by insulators to allow the mold to be heated by the heat of the polymer. This of course requires a whole new design approach to mold making itself.
A most recent method disclosed in the process of running superheated steam through the water lines in an existing mold and then, after the injection cycle is complete, pass chilled water through the mold to cool off and solidify the part so it can be removed from the mold. The manufacturing cycle time to make the part by this method is increased from 25% to 50% over normal time in order to retard the heat loss of the resin at the mold surfaces and give the nice shiney appearance which is desired. Although giving the desired finish, the cycle time is generally considered too long for the benefit received.
An object of my invention is to heat the working surface or skin cavity of the mold with a condensing vapor by injecting the vapor directly inside the mold cavity to come in contact with the skin of the mold after it is closed and quickly evacuate it of all vapors and condensate just prior to the injection cycle. Another object of the invention is to pass cooling fluid through the interior sections of the mold to cool the surface of the part from the inside out to reduce the cycle time and produce a shiney surface.
Another object of the invention is to use poppet type valves opening directly into the mold cavity for inputting the condensing vapor for heating up the mold surface and a similar valve for evacuation of the cavity. It is further an object of this invention to heat the surface of the mold to a temperature that exceeds the heat distortion point of the material being molded.
It is a further object of this invention to seal the periphery of the cavity of the mold with a seal to act as a pressure barrier in the mold to contain the condensing vapor.
It is also an object of this invention to measure the temperature of the skin or surface of the mold cavity during both the heating and cooling cycle to determine the appropriate time to inject the plastic and the proper time to open the mold after the cooling cycle.
SUMMARY OF THE INVENTION
The method and apparatus of this invention produces a shiney surface finish on foamed plastic parts which are injection molded by first passing a high pressure saturated condensing vapor through the closed mold just prior to the injection cycle to pre-heat the cavity skin of the mold to a temperature above the heat distortion temperature of the plastic to a depth of a few thousands of an inch, and then sequentially shut off the flow of vapor, evacuate the condensate and inject the plastic resin into the mold cavity. The conventional cooling by passing a cooling fluid internally through the mold then completes the cycle.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross section of a mold in a closed position in a horizontal clamp of a mold machine;
FIG. 2 is a cross section of the poppet valve in an open position in the mold; and
FIG. 3 is a cross section of the poppet valve in a closed position in the mold.
FIG. 4 is a cross section of the pressure barrier and outlet to the steam trap of mold configuration of FIG. 5.
FIG. 5 is a cross section of a mold in a closed position in a horizontal clamp of a mold machine.
FIG. 6 is a cross section of the inlet poppet valve of FIG. 5.
FIG. 7 is a cross section of the vent pin of the mold configuration of FIG. 5.
FIG. 8 is a cross section of the outlet poppet valve of FIG. 5.
DESCRIPTION OF PREFERRED EMBODIMENTS
In FIG. 1 is shown two mold halves 10 and 12 in a closed position which comprise a mold assembly 15 in the clamp section of an injection molding machine having a fixed plate 14 and a traveling plate 16 held in spaced relation by the bars 17 and clamp actuator 19. A nozzle 30 and shut off pin 32 are shown passing through the fixed plate 14 and in contact with sprue bushing 20. Sprue bore 22 connects the nozzle 30 with the internal cavity 19 of the closed mold assembly 15. Holes 25 and 26 in mold sections 10 and 12 respectively carry the cooling fluid during the cooling cycle of the process. Vent passages 27 and 28 are shown located on the parting line between mold half 10 and 12 and is the escape path for the condensing vapor which is passed through the mold during the operation cycle and is the vent passage for the gas used in the forming process of the plastic during its chill cycle. Although only two such vent passages 27 and 28 and shown, it is obvious that a number of these could and in general would exist around the mold.
Ejector pins 35 extend through the section 10 of the mold for ejecting the part upon completion of the cycle. These pins 35 are connected to ejector plate 36. The other elements of an injection molding machine are well known in the art and the method or apparatus for actuating same is not described or shown in detail here.
A poppet valve 40 is shown in FIG. 1 in its relation to the mold half 12. FIGS. 2 and 3 show the details of the valve in more easily seen detail. In FIG. 2 the valve plunger 42 has a rod end which slides in bore 43 and a head end 44 which is a conic shaped section which will seat in valve seat 48 which is also a conic section and mates closely with head end 44 to seal when closed. This seat 48 is a transition between the cavity side of mold surface 11 and the bore 50. Hole 52 is an inlet port for the vapors into bore 50. Diameter 45 of plunger 42 slides freely in bore 43 and is connected by a tension spring 54 to plate 55. An O-ring seal 56 or other suitable material seals the bore 43 to prevent vapor from escaping past plate 55 during the vapor cycles.
In FIG. 3 the poppet valve 40 is shown closed with the head end 44 of the valve shown flush with the surface 11 of mold section 12. It is obvious that the number of valves used and the locations of the valve 40 or valves would be in a location in the mold so as not to be objectionable in the part appearance. Minor differences in the surface of the part between the mold surface 11 and the head end 44 will occur.
A temperature probe 38 is shown in FIG. 1 located in mold section 12 which is used to measure the temperature of the cavity skin. This will measure the temperature for both the heating and cooling of the mold. The probe is a conventional thermocouple type well known in the art and is positioned to be within from 0.005 or 0.006 inches from the cavity surface or skin. Depending on the part to be molded and its size, this probe could be 0.035 inches from the skin.
The inside or cavity portion of the mold can be coated or impregnated with a thin layer of Teflon to act as a thermo-barrier to allow the heat of the plastic to be retained at the surface of the mold until the desired surface finish on the part is obtained. This will increase the time of the cooling portion of the cycle because the heat barrier will prevent the cooling fluid from cooling the part as quickly.
Another embodiment of my invention is shown in FIG. 5. Here an actuator 60, electrically or hydraulically operated, is connected to inlet poppet valve 62. The condensating vapor is allowed to enter the mold cavity through pipe 118 via hole 64 and cross bore 66 when valve 62 is opened as shown in FIG. 6 until it builds up a pressure of from 50 to 300 psig. At this pressure the surface temperature of the mold cavity 68 will achieve a temperature of from 250° to 420° F. which will be transferred to surfaces 70 and 72 of the mold halves 74 and 76. The inlet valve 62 is closed quickly and exhaust poppet valve 78 is opened by actuator 82, which is similar to actuator 60. The area of the exhaust valve opening to inlet valve opening has a ratio of 10:1 so that the pressurized vapor in the mold will literally explode out of the cavity carrying any condensate which may have remained on the surface of the cavity. This exhaust will exit via bore 84 and hole 86 which intersects this bore. Only a single exit is shown but obviously, many valves could be installed and synchronized to exhaust the vapor. Pipe 116 is of sufficient size to carry away the condensate and also could be a plurality of pipes depending on mold size. This cycle time of exhausting the cavity is in the order of 0.01 seconds which drops the pressure inside the mold to atmospheric and maintains the temperature of the cavity above the heat distortion temperature of the resin. The total cycle time of closing the inlet valve and opening and closing the exhaust valve is in the order of 0.25 seconds. A metallic crush-type seal 88 is retained in one mold half. This seal as manufactured by the Advanced Products Co. of North Haven, Connecticut can be used to seal the periphery of the mold as seen in FIGS. 4 and 7. Since a condensing vapor such as steam will cause water droplets to form on the surface of the mold, a steam trap 90 is provided at the lowest point in the mold to collect this moisture and still maintain the temperature inside the mold cavity. The trap 90 is connected to mold cavity 68 via tube 92, connector 94 and hole 96. Such a steam trap is manufactured by the Strong Co. of Fairview, Pennsylvania.
Actuator 98, either electrically or hydraulically operated controls a vent pin 100 which is shown in detail in FIG. 7 and will be open approximately 0.005 inches to let the gas and residual vapor escape from the mold during the injection step. Only one such actuator and pin are shown but is is obvious that a number of them could be placed around the edge of the part. This small size opening will allow spent gas, which would otherwise be trapped at the surface to be vented and yet will keep the plasticized resin contained within the mold. Ejector pins 102, shown best in FIGS. 6 and 8, have a flared end 103 which will seal the mold cavity 68 when pressurized with vapor since these pins are normally a slip fit in the mold half. These pins 102 are shown adjustable attached to ejector plate 104 by thread 108 and nuts 106.
OPERATION
After the mold halves 10 and 12 are closed and locked up by the clamp actuator 19 as shown in FIG. 1, a high pressure condensing vapor such as heated steam is allowed to enter passage 52. The spring 54 of the valve assembly 40 will open when the pressure built-up to the valve is 10 to 15 psi. The vapor will not flow into and through the cavity portion of the mold 15. Since the vent holes 27 and 28 are always open, the vapor will eventually find its way out of the mold. However, these vent holes 27 and 28 are very much smaller in area than the inlet and therefore a substantial amount of the vapor will be trapped inside the mold, condense on the skin of the mold and will heat it up to the temperature of the vapor. Condensate will then be purged from the mold by flushing the mold with a drying vapor. The type of plastic used for the foamed molded part will determine the temperature of the vapors and the temperature to which the skin of the cavity need be heated.
After the proper temperature is reached, the thermo-probe 38 will detect this temperature and the controls of the unit will simultaneously shut off the flow of the drying vapor, causing the valve 40 to close, and start injecting plastic through nozzle 30. It should be noted that the vapor used to purge the mold may be any of a number of gases available having inert qualities and capable of high heat transfer such as dry air, nitrogen, argon or helium. Also the vapor selected should not react with the plastic material to be used since the cavity will not necessarily be evacuated before injection of the plastic. Here the injection pressures would be substantially reduced because of the low-coefficient of friction between the injected plastic and the hot skin of the cavity.
When the injection of the plastic is complete, shut off pin 32 will seal off nozzle 30 and the cooling cycle will start with a cooling fluid forced through the cooling passages 25 and 26. The cooling fluid could be chilled water, carbon dioxide gas, Freon or some other cooling fluid. Here the velocity and quantity of cooling fluid passages will determine how quickly the part cools off. Again the temperature probe will determine the proper temperature for the cycle to be completed. The cooling passages may be connected in series or parallel fashion depending on the shape of the mold an attempt will be made to reduce this time as much as possible since it will account for 75% of the manufacturing cycle time.
As the mold 15 starts to open, the ejector pins 35 will cause the part to be pushed off the mold half and onto a conveyor or other device located near the mold to receive the part. The cooling fluid would now be reduced or stopped and the molding cycle started again.
The finished part would have a cellular inner structure with a shiney or glossy surface finish so that additional finishing of the part would not be required. The sprue 22 in the mold section 12 is shown as a large conical opening but in reality could be very small to allow a simple clean up operation for completing the part. Also, the material prior to injection would be colored the appropriate color so no additional finishing operations would be required.
Also in FIG. 1 only two valves 40 are shown opening into the mold cavity 18. Obviously more or less valves could be used depending on the size and structure of the part to be molded, and the heat necessary. If required, vacuum pumps could be attached to vent passages 27 and 28 to aid in vapor flow through the mold. Also the impregnating of the cavity skin with a thermo-barrier material could be made thinner or thicker on certain sections of the mold depending on the heat transfer properties of the plastic to be molded, the mold sections themselves, the vapors and cooling fluids.
FIG. 5 shows the preferred embodiment of my invention. After the mold halves 74 and 76 are closed and locked up by the clamp actuator 110, a high pressure and high temperature condensing vapor such as super heated steam is allowed to enter passage 64. The poppet valves 62 and 78 would be in a de-energized or closed position. The valve 62 will be opened by actuator 60 and the vapor will now flow into and throughout the mold cavity 68 heating it up. The crushable seal 88 will prevent the vapor from escaping and the pressure inside the cavity may reach 300 psig. A substantial amount of the vapor will condense on the skin of the mold and will heat it up to the temperature of the vapor. Condensate will accumulate until droplets are formed and these will purge from the mold via the steam trap 90 by the internal pressure in the mold. The type of plastic used for the foamed molded part will determine the temperature of the vapors and the temperature to which the skin of the cavity need be heated.
After the proper temperature is reached, the controls of the unit will simultaneously shut off the flow of the condensing vapor by actuator 60 causing the valve 62 to close, and open exhaust valve 78 with actuator 82. Since the relative size of the inlet valve to the exhaust valve is substantially larger and at least 1:2, any condensate which may not have been forced into the steam trap would now be blown out the exhaust valve 78. The total cycle time to purge the mold would be less than 0.25 seconds. If part size or other restrictions prevent an exhaust from being installed in the mold, the mold halves themselves could be momentarily separated to let out condensate which did not get forced into the steam trap.
Upon completion of either purge method, the controls will now start injecting plastic through nozzle 112. It should be noted that the vapor selected to heat the mold halves should not react with the plastic material. As the mold is filling, vent pin actuator 98 will be energized, as shown in FIG. 7, to vent the cavity 68 of the mold halves. The opening will be approximately 0.005 inches. Also the injection pressures would be substantially reduced because of the low-efficient of friction between the injected plastic and the hot skin of the cavity. The heated surface will keep melting the surface of the part in contact with the mold and produce the desired results.
When the injection of the plastic is complete, shut off pin 114 will seal off nozzle 112 and the cooling cycle will start with a cooling fluid forced through the cooling passages 124 and 126. The cooling fluid could be chilled water, carbon dioxide gas, Freon or some other cooling fluid. Here the velocity and quantity of cooling fluid passages will determine how quickly the part cools off. Again the size and shape of the part and type of plastic resin will determine the proper temperature and cycle time for the part to be molded. The cooling passages may be connected in series or parallel fashion depending on the shape of the part. An attempt will be made to reduce this time as much as posible since it will account for 75% of the manufacturing cycle time.
As the mold halves 74 and 76 start to open, the vent pin actuator 98 will de-energize and ejector pins 102 will cause the part to be pushed off the mold half 74 and onto a conveyor or other device located near the mold to receive the part. The cooling fluid would now be reduced or stopped and the molding cycle started again.
The finished part would have a cellular inner structure with a shiney or glossy surface finish so that additional finishing of the part would not be required. The sprue 115 in the mold section 76 is shown as a large conical opening but in reality could be very small to allow a simple clean up operation for completing the part. Also, the plastic material prior to injection could be colored the appropriate color so no additional finishing operations would be required.
Also in FIG. 5 only a single valve is shown for each inlet and exhaust valve. Also a single vent pin 100 and actuator 98 are shown. Obviously additional inlet and exhaust valves and vent pins could be used depending on the size and structure of the part to be molded, and the temperature necessary. If required, a vacuum pump could be attached to exhaust passage 86 via pipe 116 to aid in exhausting trapped condensate from the mold. Also the impregnating of the cavity skin with a thermo-barrier material could be made thinner or thicker on certain sections of the mold depending on the heat transfer properties of the plastic to be molded, the mold sections themselves, the vapors and cooling fluids.
While certain embodiments and details have been shown to illustrate the invention, it will be apparent to those skilled in the art that various changes and modifications could be made therein without departing from the spirit or scope of the invention described in the appended claims.
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This invention substantially improves the surface finish on resin filled foamed molded plastic products manufactured by injection molding by pre-heating the skin surface of that part of the mold in contact with the part prior to the injection cycle of the machine and then subsequently chilling the mold via internal tube connections to shorten the time needed in the manufacturing cycle for solidifying the part sufficiently for release from the mold.
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BACKGROUND OF THE INVENTION
The present invention relates to a subdivided control valve body for injector control valve.
In fuel injection systems for injection of fuel under pressure into the combustion chambers of direct injection internal combustion engines, an injection system with a high pressure collecting chamber (common rail) is utilized. It loads the injector provided for the injection with fuel under high pressure, and its pressure level remains substantially constant. In the injectors, the injection start as well as the fuel quantity injected in the combustion chamber is adjustable. The injector is electrically controlled and mounted on a cylinder head of an internal combustion engine in a space-economical manner.
German patent document DE 197 01 879 A1 discloses a fuel injection device for internal combustion engines. The disclosed fuel injection device for internal combustion engines includes a common high pressure collecting chamber which is fillable from a high pressure pump with fuel (common rail). It is connected through injection lines with injection valves which extend into the combustion chamber of the internal combustion engine to be supplied with fuel. Its opening and closing movements are controlled each by an electrically controlled control valve, wherein the control valve is formed as a 3/2-way valve. It is connected with an injection line or a release line by a high pressure passage which opens to an injection opening of the injection valve. A hydraulic working chamber which is fillable with high pressure fuel is provided on the control member of the control valve. It is controllable for adjusting the adjustment position of the control member of the control valve in a release passage.
The control member used in the 3/2-way control valve in accordance with this solution is formed with a plurality of diameter steps. On the one hand it is therefore difficult to obtain an undisturbed force equalization of the control member, and on the other hand the manufacturing costs are negatively influenced, since several operation steps have to be made on the control valve workpiece during its manufacture.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a valve body for an injector control valve, which avoids the disadvantages of the prior art.
In keeping with these objects and with others which will become apparent hereinafter, one feature of present invention resides, briefly stated, in a combustion chamber of an internal combustion engine, comprising an injector housing; a control valve body which is movably received in said injector housing; an actuating unit which activates said control valve body; a restoring element associated with an end side of said control valve body, said control valve body having parts which are held against one another; and a connecting element which holds said parts of said control valve body against one another.
When the control valve is designed in accordance with the present invention, it is easy to manufacture, and with the use of the modular principle and identical parts it can be designed so that a control body can be assembled with two identical parts. The both halves of the inventive control valve body can be held at the end surfaces by clamping elements which engage in the planar position the surfaces which abut against one another.
In accordance with another feature of the present invention which is especially favorable for simple manufacture, the clamping element can be centered on a pin of one half of the inventive control body and fixed. On the other half of the control body the clamping element engages over the end surface and is provided with a radial play with respect to the pin formed on the end surface of this half. With this solution it is guaranteed that the control part halves are not separated in the axial direction on the one hand, and it is possible to radially orient one half of the control body with respect to the other half of the control body in the openings of the control valve housing. In this way manufacturing tolerances can be compensated in an advantageous manner.
In accordance with another advantageous feature of the present invention, the clamping element which holds together the symmetrically constructed halves of the control valve body is accommodated in the region of the control valve housing which is closed from the valve chamber of the control valve. One half of the inventive control body is received in one housing half, while the other half of the control valve body is located in the other housing half of a two-part injector housing. Thereby on the one hand the housing can be separated during mounting in a simple manner, and on another hand the required housing tolerances can be produced in a favorable manner for the manufacture, since the opening—and position tolerances can be compensated by the radial gap between the halves of the control valve.
The novel features which are considered as characteristic for the present invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, 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
FIG. 1 is a view showing a longitudinal section of a control body in accordance with the present invention; and
FIG. 2 is a view showing a cross-section through a pin of an upper part of the control piston which is surrounded by a clamping element.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A control valve in accordance with the present invention is illustrated in FIG. 1 in a longitudinal section. In the embodiment shown in FIG. 1 a housing 1 which receives a control valve body 7 is composed of two parts. The upper part 2 of the housing and the lower part 3 of the housing abut against one another over a common separation joint 4 . The separation joint extends preferably in the region of a valve chamber 14 which surrounds the control valve 7 in the housing 1 of the injector.
The upper half 8 of the control valve body 7 is formed in an upper opening region 5 inside the upper housing half 2 in a diameter 10 . The guiding region of the upper half 8 of the control valve body 7 formed in the diameter 10 , with which it is guided in the upper opening portion 5 , is followed by a constriction 12 . Inside the constriction 12 , the upper part 2 of the housing opens into an outlet opening 13 . A seat cone 15 is connected with the constriction 12 of the upper part 8 of the control body 7 and cooperates with a seat surface 16 which is formed in the housing. The seat cone 15 transits into a surface which surrounds it in a ring-shaped manner. Under the surface which follows the seat cone 15 , the upper half 8 of the control body 7 has a pin 18 . An end surface 19 of the upper part 8 of the control valve body 7 is connected with the pin 18 .
A lower half 9 of the control body 7 is received movably in the lower part of the housing, symmetrically to the upper part 8 of the control valve body 7 . The lower part 9 of the control valve body 7 is identical to the upper part 8 of the control valve body 7 , however, they are arranged mirror-symmetrically with respect to a common abutment surface 20 . This means that the lower half 9 of the control valve body 7 also has an abutment surface formed on an end surface, on which a pin region 26 is connected. A ring-shaped projection 28 is connected with the pin region 26 of the lower half 9 of the control valve body 7 and transits into an inner seat cone 27 on the lower half 9 of the control valve body 7 .
A constriction 28 is connected with the seat cone 27 , which in turn transits into a guiding portion. The latter has a control valve diameter 10 which is identical to the diameter of the upper half 8 of the control valve body 8 . A pin-shaped projection 31 is formed on the lower side of the lower half 9 of the control valve body 7 . It serves as a guide for a restoring element formed as a spiral spring 32 . The restoring element 32 formed as a spiral spring is supported on the housing, in particular on a not shown wall. Opposite to the constriction 28 of the lower half 9 of the control valve body, an inlet 30 opens into the lower part 3 of the housing. Fuel under high pressure from the high pressure collecting chamber enters through the inlet 30 in the constriction 28 of the lower half 9 of the control valve body 7 and the wall of the lower part 3 of the housing.
A connecting element 21 formed as a spring clip is provided in the region of the contact surface 20 and the opposite, abutting end sides of the upper half 8 and the lower half 9 of the control valve body 7 . The connecting element 21 which is formed as a spring clip of a metallic material form-lockingly lies on the pin 18 on the upper supporting surface 22 . The connecting element 21 is fixed and centered on the pin 18 . At the side of the lower half 9 of the control valve body 7 which is opposite to the abutment surface 20 , the connecting element 21 lies in the ring-shaped abutment 37 which engages with the end surface of the lower half 9 of the control valve body 7 . The abutment of the connecting element 21 on the rear side of the end surface of the lower half 8 of the control valve body 7 is dimensioned so that, between the connecting element 21 and a pin 26 of the lower half 9 of the control valve body 7 , a radial gap 24 is provided.
During a vertical stroke released by activation of the actuation element 11 , an adjusted separation of the upper half 8 and the lower half 9 of the control valve body 7 at the abutment surface 20 is excluded by the connecting element 21 which engages over the end surfaces of the upper half 8 of the control valve member 7 and the lower half 9 contacting one another on the abutment surface 20 . However, the connecting element 21 , because of the radial gap 24 between the pin 26 and the abutment surface formed ring-shaped at the rear side of the end surface of the lower half 9 of the control valve body 7 , allows a radial movement of the lower half 9 of the control valve body 7 relative to the upper half of the control valve body 7 .
The housing 1 , in which the upper half 8 as well as the lower half 9 of the assembled control valve body 7 are guided, can be formed as a two-part housing including an upper housing part 2 and a lower housing part 3 .
When the housing 1 , in which the upper half 8 and the lower half 9 of the assembled control valve body 7 are guided, is formed as a two-part housing including the upper part 2 and the lower part 3 , then favorable manufacturing tolerances with respect to the opening tolerances and the position tolerances of the opening portions 5 and 6 in the upper part 2 and the lower part 3 of the housing can be selected. This drastically reduces the manufacturing costs of the control valve body 7 in accordance with the present invention on the one hand, since now a compensation of tolerances is possible by a radial movement of the half 8 , 9 of the control valve body 7 relative to the other halves 8 , 9 of the control valve body 7 . Thereby on the one hand the hubs 8 and 9 of the control valve body 7 can be produced in a cost favorable manner, and on the other side the opening portions 5 , 6 in the upper housing part 2 and in the lower housing part 3 can be also produced in a cost favorable manner.
A further not insignificant advantage of the inventive solution is that, with the use of identical parts a mirror-symmetrical construction of the assembled control valve body 7 can be provided. Furthermore, the inventive solution provides the advantage in that, the assembled control valve body 7 composed of the upper half and the lower half 9 is completely force-compensated. The reason is that both the seat cones 15 and 27 as well as the end surfaces 16 , 29 in the upper part 2 and in the lower part 3 of the housing are identical. Furthermore, the guiding regions 10 with which the upper half 8 and the lower part 9 of the assembled control valve 7 are guided correspondingly in the upper part 2 and the lower part 3 of the housing are formed with an identical diameter 10 .
FIG. 2 illustrates the cross-section through the pins of the upper half of the control valve body surrounded by the connecting element. The cross-section of FIG. 2 is identified as II/II in FIG. 1 and extends through the pin 18 which extends between a ring-shaped surface of the upper half 8 of the control valve body 7 and its end surface, which in turn is surrounded by the connecting element 21 . From FIG. 2 it can be seen that the spring element 20 is held in abutment to the pin 18 of the upper half 8 of the control valve body 7 . Due to the abutment of the connecting element 21 against the pin 18 of the upper half 8 of the control valve body 7 , a substantial ring-shaped abutment surface 34 between the connecting element 21 and the outer side of the pin 18 is produced. The ring-shaped extending abutment surface region 34 is interrupted by a gap 35 as well as by an opening 33 .
The spring element 21 which is composed preferably of a metallic material such as for example high grade steel, is provided with a rounding 36 and surrounds the pin 18 of the upper half 8 of the control valve body 7 in the abutment surface 34 and the pin 26 of the lower half 9 of the control valve body 7 in the ring-shaped abutment 37 , on its upper end surface as well as with a radial gap 24 with respect to the pin 26 of the lower half 9 . In this way differences in the opening portions 5 and 6 of the upper part 2 and the lower part 3 of the housing due to the manufacturing tolerances can be compensated, and simultaneously a separation of the upper half 8 and the lower half 9 of the control valve body 7 during radial strokes produced during a regulation of the control element 1 can be prevented.
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 constructions differing from the types described above.
While the invention has been illustrated and described as embodied in subdivided control valve body for injector control valve, 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.
What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.
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An injector for injecting fuel under high pressure into a combustion chamber of an internal combustion engine has an injector housing, a control valve body which is movably received in the injector housing, an actuating unit which activates the control valve body, a restoring element associated with an end side of the control valve body, the control valve body has parts which are held against one another, and a connecting element which holds the parts of the control valve body against one another.
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CROSS-REFERENCE TO RELATED PATENT
This application is a continuation-in-part of U.S. application Ser. No. 587,054, filed Mar. 7, 1984, and now U.S. Pat. No. 4,560,318 granted Dec. 24, 1985.
BACKGROUND OF THE INVENTION
This invention relates to attachments for back hoe buckets of vehicles, and more particularly, to an attachment including a fork lifting device.
There have been many attachments to buckets of vehicles, both front and back types of buckets, as shown by the following U.S. Pat. Nos.:
______________________________________2,421,472 Way 3,921,837 Vandewater2,488,695 Upton 4,056,205 Etzler2,577,977 Nelson 4,120,405 Jones et al3,312,361 Foster 4,125,952 Jennings3,421,642 Carter 4,172,687 Schultz3,440,744 Smith 4,175,900 Etzler3,665,622 Lamb 4,200,423 Sornsin3,667,633 Cappella 4,242,035 Hornstein3,706,388 Westendorf 4,247,243 Carter3,749,262 Stark 4,275,985 Schremmer3,807,802 Betters 4,329,103 Miller3,812,979 Leihgeber 4,360,980 Jarvis______________________________________
and by British Pat. No. 1,373,646.
The prior art attachments are often complex in design, expensive to manufacture and not readily installed and/or maintained. Often the entire attachment must be removed from the bucket to enable use of the bucket in the intended manner. These and other problems are believed to be substantially alleviated by the attachment according to the hereinafter disclosed invention.
SUMMARY OF THE INVENTION
The attachment for a back hoe bucket according to this invention includes a pair of elongated spaced support arms secured to and extending above respective side walls of the back hoe bucket adjacent the rear wall thereof, and each arm has an opening therethrough adjacent its upper end in substantial alignment with each other laterally of the bucket with each bottom wall forming the opening being generally flush with an upper edge of respective side wall of the bucket. An elongated upper bar extends laterally outwardly through the aligned openings in the arms and supported by the arms and adapted to be supported by the upper edge of the side walls of the bucket. A pair of elongated generally upright members each include lower and upper ends supported by the upper bar outboard of respective arms. Selective means releasably attach each of the upper ends of the upright members in selected lateral positions on the upper bar. An elongated lower bar extends substantially parallel to the upper bar, and means are provided to attach the lower bar to each of the upright members spacedly above the lower ends and generally below a back hoe bucket attachment to a boom of a back hoe vehicle to dispose the lower bar supportingly against a back wall of the bucket spaced adjacently above its bottom wall.
In other aspects the attachment in accord with this invention is provided with a pair of fork lift prongs respectively attached to the lower ends of the upright members and extend generally horizontally of the upright members. The means to attach the lower bar to each of the upright members may include a pair of support means carrying the lower bar and adjustable clamp means connected between respective support means and the upright member to selectively adjust the position of each of the support means along respective upright members. The upright members may have elongated slots with the clamp means including a pair of threaded bolts passing through respective support means and the lower bar and the upright member through the elongated slot and a pair of nut fasteners threadedly engaged on the bolts to releasably affix the lower bar in selected positions along the slots. The means to attach the lower bar to each of the upright members includes a clamp means slideable on each of the upright members, means to releasably affix the clamp means to the upright members, and support means carried by the clamp means for supporting the lower bar. The clamp means includes a hollow box element and the means to releasably affix the clamp means includes a set screw threadedly engaged with one wall of the box element with an inner end of the set screw selectively engaging the upright member passing through the hollow box element. Each support means carried by the clamp means may include at least one plate extending laterally of each box element between the upright member and the back wall of the bucket, and the one plate has an opening through which the lower bar extends. Each support means may also include another substantially identical plate extending laterally of each box element and parallel to the one plate.
In yet other aspects, the attachment according to this invention is seen to include releasable means for securing each of the spaced support arms to respective side walls of the bucket, the releasable means including a first bolt and nut fastener passing through and fastened about a first opening in each support arm below the opening receiving the upper bar in the upper end of the arm, and an aligned opening in the bucket, and a second bolt and nut fastener passing through and fastened about an arcuate slotted second opening in each support arm below the first opening and another aligned opening in the bucket generally located centrally of the second opening to permit angular adjustment of the support arms about the first bolt and nut fastener.
Further aspects in accord with this invention are directed to the provision of the selective means to releasably affix each upright upper end to the upper bar includes a set screw threadedly engaged with the upright upper end and engaging the upper bar. In an alternate embodiment each selective means includes a bolt and nut fastener passing through and secured to respective upright member and the upper bar. Each upright member includes a hollow box element forming each upper end thereof with the upper bar passing through the hollow of respective box element, the nut and head of the bolt engaging on opposite side walls of the box element with the bolt passing through the opposite side walls and the upper bar.
Additional aspects are provided to the attachment according to this invention wherein each upright member includes a hollow box element forming each upper end thereof with the upper bar passing through the hollow of respective box element. Each selective means is engaged on the box element and engages the upper bar. The selective means includes a set screw threadedly engaged with one wall of the box element and engaging the upper bar internally of the box element. The upper bar may be hollow and may conform in shape to the hollow box element with such shapes being complementary and are substantially square. Therefore the lower bar may be substantially square and each of the means to attach the lower bar to each of the upright members includes a pair of support means having a substantially square opening receiving the square lower bar. The lower bar may be substantially round and each of the means to attach the lower bar to each of the upright members includes a pair of support means having a substantially round opening receiving the round lower bar.
The principal object of this invention is to provide an attachment to a back hoe bucket to be employed to load and unload pipe from trucks without detaching the bucket.
Another object of this invention is to provide an attachment which is adaptable to also string pipe, and does not use chains, which are dangerous when applied to P.V.C. pipes to inhibit slippage.
Another object of this invention is to provide an attachable fork lifting device, which will be of such design, as to require only one man to perform the task of loading and unloading pipe.
A further object of this invention is to provide a fork lifting attachment, which will be removably supported on the bucket portion of the back hoe vehicle.
A still further object of this invention is to provide a fork lifting attachment which will be easily adjustable to handle various lengths of pipe, as long as twenty feet, safely.
Other objects of the invention are to provide a fork lifting attachment which will be simple in design, inexpensive to manufacture, rugged in construction, and easy to install and maintain.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features which are believed to be characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings, in which:
FIG. 1 is a perspective view of the attachment in accord with the first embodiment of the present invention, shown installed on the bucket of a back hoe vehicle, and illustrating pipes thereon, in phantom;
FIG. 2 is an enlarged cross-sectional view, taken along line 2--2 of FIG. 1;
FIG. 3 is an enlarged view, taken along line 3--3 of FIG. 1;
FIG. 4 is a side elevational view of the attachment in accord with the second embodiment of the present invention;
FIG. 5 is a slightly enlarged front elevational view of the attachment of FIG. 4;
FIG. 6 is an enlarged side elevational view of the upper portion of the attachment of FIG. 4;
FIG. 7 is a front elevational view of the upper portion of FIG. 6;
FIG. 8 is an enlarged detail of the connection through the slot in the plate shown in FIGS. 6 and 7; and
FIG. 9 is an enlarged perspective view of a portion of the spanning lower bar between the forks shown in FIGS. 4 and 5.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
According to the first embodiment of the invention the attachment 11 is generally depicted as a fork lifting device and includes a pair of flat prongs 12, that are common in the art for loading and unloading types of vehicles. The prongs 12 are angularly formed at their upper portions 13 and terminate by means of a box like eye 14, formed integrally therewith, and which freely and slideably receives an upper elongated steel member or bar 15, which in this instance, is of square cross-sectional configuration, which is preferably about nine feet in length for horizontal adjustment of spread between the prongs 12 of fork attachment 11, as indicated by means of the arrows 16. Bar 15 is also slideably received within the openings 15a of spaced mounting arms 18 which extend above the upper edges of side walls 20 of bucket 21. The prongs 12 in this instance, provide a means of supporting pipe 17 in an angularly rearward and cradled manner, to be loaded from one vehicle to another. However, the function of attachment 10 is not limited to lifting and moving pipe, as it may be employed to lift and move other material, such as lumber, etc.
The lower ends of arms 18 are fixedly secured by bolt fasteners 19, to the rear portions of the side walls 20 of bucket 21 of a back hoe vehicle (which is not shown) including the support arm illustrated by broken lines 33 in FIG. 1. Each eye 14 includes openings 22 therethrough, which freely receives a bolt fastener 23, and bolt fasteners 23 are also freely received through a selected one of a plurality of spaced transverse openings 24, bored through bar 15. The fork attachment 11 has its prongs 12 spread apart from each other, to any desired distance, by the bolt fasteners 23 being received in any of the aligned openings 24 chosen, and nut fasteners 25 are threaded onto bolt fasteners 23, so as to render the adjustment secure.
A second lower elongated bar 26 is provided and disposed adjustably below upper bar 15 on prongs 12, for increased rigidity and stability of fork attachment 11 in picking up and supporting pipe 17 on the fork attachment 11 and onto several portions of the bucket. Bar 26 includes a pair of channel clamps 27, of "V"-shaped configuration, in which bar 26 is received slideably for the same general type of adjustment, above described with respect to bar 15. A bolt fastener 28 is freely received in an opening 29 of each channel clamp 27, and is freely received within any one of the desired transverse openings 30 through lower bar 26. Bolt fasteners 28 are freely and adjustably received within respective elongated cut-out openings or slots 31 through the upper portions 13 of prongs 12 of fork attachment 11. Bolt fasteners 28 render bar 26 secured at any desired elevation on prongs 12, by nut fasteners 32 spanning the slots 31 and being tightened against upper portions 13. It should be noted, that the upper bar 15 is disposed on top of the bucket 21 and preferably rests thereon, and is spaced from the support arm 33 of the back hoe vehicle, so as to prevent any interference therewith, when the vehicle and the fork lift attachment are in operation.
In use, the back hoe vehicle is operated in the usual manner, with the exception, that the operator backs the bucket 21 in such a manner, as to cause the forward end of the prongs 12 to guide beneath pipe 17. The operator then pivots the bucket 21 in the usual manner to cause the pipe 17 to lay in the arcuate portions between upper portions 13 and the prongs 12. The operator then lifts the fork attachment 11 and pivots the bucket 21 and fork attachment 11 combination away from the point of pick-up. The fork attachment 11 is then positioned at the unloading site or a vehicle that is to receive the pipe 17. After the above-mentioned, the operator then pivots the bucket 21 and fork attachment 11 combination, while lowering same, to discharge the pipe 17 smoothly therefrom.
A preferred embodiment is illustrated in FIGS. 4-9 in which the attachment 40 for bucket 41 comprises a pair of up-standing arms 42 connected to the side walls 43 of bucket 41 by appropriate bolt, washer and nut fasteners, illustrated in FIG. 8 by bolt 44, washer 45 which may be a lock washer) and nut 46. When attaching arms 42, the flat bottom 47' of square opening 47 through plate 42 is aligned with the top of the bucket 41 closely adjacent the back wall 48 of the bucket 41 and the upper opening 49 is drilled along with another hole 50 spaced downwardly therefrom. Plate 42 includes a hole 51 aligned with hole 49, through which a bolt, washer and nut fasten plate 42 to side wall 43, and an arcuate slot 52 which adjustably aligns with opening 50 to dispose plate 42 in proper angular relation to align opening 47 above side wall and to dispose the remainder of the fork attachment 40 with respect to the rear wall 48 of the bucket 41. As seen in FIGS. 6 and 8, the slot 52 receives bolt 44 at the lowest valley of the slot while the upper extent of the slot is illustrated by broken line 52' in FIG. 8.
The fork attachment 40 includes a pair of spaced fork arms 55 having upper generally upright portions 56 and generally lateral portions or prongs 57. The upper portions 56 terminate in an eye, in the form of a box element 58 which are positioned on elongated upper box member 59, box member 59 being freely received in opening 60 of each box element 58 and through openings 47 in plates 42. The lateral position of the box element 58 on box member 58 is adjustably secured thereto by an Allen or the like set screw 61 threaded into a wall of element 58, herein shown as top wall 62. As shown in FIG. 5, the fork arms 55 are shown in the minimum distance apart and may be adjusted outwardly to adjacent the free ends 63 of box member 59. It is to be noted that box member 59 also is shown resting on and supported by the top of the bucket as seen in FIG. 5.
The upright portions 56 adjacently above the prongs 57 respectively carry box elements 65 freely slideable on portions 56 and adjustably secured in selected positions by Allen or the like type set screws 66. A pair of spaced plates 67 are rigidly affixed to and extend rearwardly away from the prongs 57. Openings 68 are provided in each plate 67 of both box elements 65 and freely receive an elongated lower member 69, member 69 being appropriately engaged against bucket rear wall 48 to provide support therefor during load shifting when bucket 41 is pivoted to dispose the pipe in the arcuate portion between prongs 57 and upper portions 56, as hereinabove described. The lower member 69 is preferably a round pipe but a rectangular member similar to box member 59 may be employed, if desired. While not necessary, a releasable means may be employed between the member 69 and the plates 67 (or element 65) to prevent any inadvertent dislodgement of member 69 laterally from openings 68. A common push pin or cotter pin may pass through openings adjacent the free ends of member 69 or a hose clamp or the like may be employed about member 69 adjacent and outboard of either plate 68 attached to either box element 65.
It will be appreciated that while this embodiment is also shown as a fork lift attachment, other attachments may be configured employing the same basic construction shown herein, except, for example, the prongs would be eliminated and a scraper blade may be attached to the upright portions 56 and thus the scraper blade can be used to move and/or level dirt or the like without detachment of the back hoe bucket. Other similar earth working attachments can similarly be configured on the same basic construction described herein without departing from this invention.
While the invention has been described with respect to certain specific embodiments, it will be appreciated that many modifications and changes may be made by those skilled in the art without departing from the spirit of the invention. It is intended, therefore, by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention.
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The attachment includes a pair of spaced support arms secured to the sides of a bucket of a back hoe vehicle and receive an elongated upper rectangular bar, and a pair of adjustably spaced fork arms attached to the upper bar. An elongated lower bar extends substantially parallel to the upper bar and is adjustably supported by the fork arms and engages against the back wall of the bucket. The lower bar may be adjustably elevated on the fork arms and provides rigidifying support for the fork arms in their outwardly extended position.
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REFERENCE TO RELATED APPLICATIONS
[0001] This is a non-provisional patent application claiming the benefit of the filing date of U.S. Provisional Application Ser. No. 60/389,790 filed on Jun. 19, 2002 and Ser. No. 60/361,124 filed on Mar. 1, 2002 which are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention pertains to copolymers useful for photoimaging compositions. These copolymers are comprised of a fluoroalcohol or protected fluoroalcohol functional group and a repeat unit derived from an acrylate monomer containing a fluoroalkyl group or a hydroxyl substituted alkyl group. Such groups have been found to promote adhesion of the copolymers, and photoresists derived from such copolymers, to substrates used in the manufacture of semiconductor devices. The copolymers are especially useful in photoresist compositions having high UV transparency (particularly at short wavelengths, e.g., 193 nm and 157 nm).
[0004] 2. Description of Related Art
[0005] Polymer products are used as components of imaging and photosensitive systems and particularly in photoimaging systems. In such systems, ultraviolet (UV) light or other electromagnetic radiation impinges on a material containing a photoactive component to induce a physical or chemical change in that material. A useful or latent image is thereby produced which can be processed into a useful image for semiconductor device fabrication.
[0006] For imaging features at the submicron level in semiconductor devices, electromagnetic radiation in the far or extreme ultraviolet (UV) is needed. Photolithography using 193 nm exposure is a leading candidate for future microelectronics fabrication using 0.18 and 0.13 μm design rules; photolithography using 157 nm exposure may be needed for 0.100 μm or less design rules. The opacity of traditional near-UV and far-UV organic photoresists at 193 nm or shorter wavelengths precludes their use in single-layer schemes at 157. nm.
[0007] Photoresists comprising copolymers with fluoroalcohol functional groups have been disclosed in WO 00/67072.
[0008] Copolymers of fluorinated alcohol monomers with other comonomers have been reported (U.S. Pat. No. 3,444,148 and JP 62186907 A2). These patents are directed to membrane or other non-photosensitive films or fibers, and do not teach the use of fluorinated alcohol comonomers in photosensitive layers (e.g., resists).
[0009] There is a critical need for other novel resist compositions that have high transparency at 193 nm, and more preferably at or below 157 nm, and also have other key properties such as good plasma etch resistance and adhesive properties.
SUMMARY OF THE INVENTION
[0010] This invention relates to a fluorine-containing copolymer comprising:
[0011] a. a first repeat unit derived from an ethylenically unsaturated compound containing a functional group having the structure:
—X r (CH 2 ) q C(R f )(R f ′)OR a
wherein
R f and R f ′ are the same or different fluoroalkyl groups of from 1 to 10 carbon atoms, or taken together are (CF 2 ) n ; n is an integer from 2 to 10; X is selected from the group consisting of S, O, N, and P; q=0 and r=0, or q=1 and r=0 or 1; and R a is H or an acid- or base-labile protecting group; and
[0018] b. a second repeat unit derived from CH 2 ═CRCO 2 CH 2 R″,
[heading-0019] wherein
[none]
R″ is a fluoroalkyl group of 1 to 4 carbon atoms or a hydroxyalkyl group of 1 to 4 carbon atoms; and
R is H, F, an alkyl group of 1 to 5 carbon atoms, or a fluoroalkyl group of 1 to 5 carbon atoms.
[0022] The copolymers of this invention are useful as the base resin in photoresist compositions comprising the copolymers of this invention, a photoactive component, and optionally other additives. Processes for preparing a photoresist image on a substrate using such photoresists are also disclosed herein.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] Fluorinated Alcohol Copolymers
[0024] A fluorine-containing copolymer of this invention comprises a repeat unit derived from at least one ethylenically unsaturated compound containing functional group derived from a fluoroalcohol or protected fluoroalcohol functional group. This functional group contains fluoroalkyl groups, designated R f and R f ′, which can be partially or fully fluorinated alkyl groups. R f and R f ′ are the same or different fluoroalkyl groups of from 1 to 10 carbon atoms or taken together are (CF 2 ) n wherein n is 2 to 10. The terms “taken together” indicate that R f and R f ′ are not separate, discrete fluorinated alkyl groups, but that together they form a ring structure such as is illustrated below in case of a 5-membered ring:
[0025] R f and R f ′ must be sufficiently fluorinated to impart acidity to the hydroxyl (—OH) of the corresponding fluoroalcohol functional group, such that the hydroxyl proton can be substantially removed in basic media (e.g., aqueous sodium hydroxide or tetraalkylammonium hydroxide solution). Preferably, there is sufficient fluorine in the fluoroalcohol functional group such that the hydroxyl group has a pKa value of 5<pKa<11. Preferably, R f and R f ′ are independently perfluoroalkyl groups of 1 to 5 carbon atoms, most preferably, trifluoromethyl (CF 3 ). The number of fluoroalcohol groups is determined for a given composition by optimizing the amount needed for good development in aqueous alkaline developer.
[0026] More specfically, the fluorine-containing copolymers comprise a repeat unit derived from at least one ethylenically unsaturated compound containing a fluoroalcohol functional group or a protected fluoroalcohol functional group having the structure:
—X r (CH 2 ) q C(R f )(R f ′)Or a
wherein R f and R f ′ are the same or different fluoroalkyl groups of from 1 to 10 carbon atoms, or taken together are (CF 2 ) n ; n is an integer from 2 to 10; X is selected from the group consisting of S, O, N, and P; q =0 and r=0, or q=1 and r=0 or 1; and R a is H or an acid- or base-labile protecting group which can be cleaved by photo-generated acid or base (vide infra). Preferably, X is O.
[0028] Some illustrative, but nonlimiting, examples of representative comonomers containing a fluoroalcohol functional group that are within the scope of the invention are presented below:
[0029] The fluorine-containing copolymer further comprises a repeat unit derived from an acrylate monomer, CH 2 ═CRCO 2 CH 2 R″, where R″ is a fluoroalkyl group of 1 to 4 carbon atoms or a hydroxyalkyl group of 1 to 4 carbon atoms, and R is H, F, an alkyl group of 1 to 5 carbon atoms, or a fluoroalkyl group of 1 to 5 carbon atoms.
[0030] When R″ is a fluoroalkyl group, it can be fully or partially fluorinated and the arrangement of carbon atoms can be straight-chain or branched (for fluoroalkyl groups of 3 or 4 carbon atoms). Suitable fluoroalkyl R″ groups include perfluoromethyl, perfluoroethyl and perfluoroisopropyl, with perfluoromethyl being preferred. Suitable hydroxyalkyl R″ groups include primary hydroxyalkyls, —(CH 2 ) m OH, where m =1, 2, 3 or 4.
[0031] When R is a fluoroalkyl group, it can be fully or partially fluorinated and the arrangement of carbon atoms can be straight-chain or branched (for fluoroalkyl groups of 3-5 carbon atoms). Preferably, R is H or methyl, most preferably R is H.
[0032] Two representative examples of suitable acrylates and their corresponding repeat units are given below:
[0033] The fluorine containing copolymer can also comprise a repeat unit derived from an ethylenically unsaturated compound containing at least one fluorine atom attached to an ethylenically unsaturated carbon. This fluoroolefin comprises 2 to 20 carbon atoms. Representative fluoroolefins include, but are not limited to, tetrafluoroethylene, hexafluoropropylene, chlorotrifluoroethylene, vinylidene fluoride, vinyl fluoride, perfluoro-(2,2-dimethyl-1,3-dioxole), perfluoro-(2-methylene4-methyl-1,3-dioxolane), CF 2 ═CFO(CF 2 ) t CF═CF 2 , where t is 1 or 2, and R f ″OCF═CF 2 wherein R f ″ is a fluoroalkyl group of from 1 to 10 carbon atoms. A preferred fluoroolefin is tetrafluoroethylene.
[0034] One or more repeat units of the copolymer of this invention can be cyclic or polycyclic.
[0035] Bifunctional compounds that can initially afford crosslinking and subsequently be cleaved (e.g., upon exposure to strong acid) are also useful as comonomers in the copolymers of this invention. Photoresist compositions, incorporating copolymers comprising these bifunctional monomers, can have improved development and imaging characteristics, since exposure to light photochemically generates strong acid or base, which cleaves the bifunctional group. This results in a very significant drop in molecular weight, which can lead to greatly improved development and imaging characteristics (e.g., improved contrast).
[0036] The preferred process for polymerizing the fluorine-containing copolymers of this invention, is radical addition polymerization, which was found to avoid the problem of the hydroxy-functionalized acrylate interfering with the polymerization catalyst. Any suitable polymerization initiator, such as di-(4-tert-butylcyclohexyl)peroxy-dicarbonate, can be used under appropriate conditions. The polymerization pressure can range from about 50 to about 10,000 psig, preferably from about 200 to about 1,000 psig. The polymerization temperature can range from about 30° C. to about 120° C., preferably from about 40° C. to about 80° C. Suitable solvents include 1,1,2-trichlorofluoroethane and non-chlorofluorocarbon solvents such as 1,1,1,3,3-pentafluorobutane. The polymerization process is further enhanced by a semi-batch synthesis. In the semibatch synthesis, a part of the monomer mixture is placed in the reaction vessel and then, portionwise or continuously, the remaining monomers and initiator are added to the vessel throughout the polymerization process.
[0037] Each fluorine-containing copolymer of this invention has an absorption coefficient of less than 4.0 μm −1 at 157 nm, preferably less than 3.5 μm −1 at 157 nm, more preferably, less than 3.0 μm −1 at 157 nm, and, still more preferably, less than 2.5 μm −1 at 157 nm.
[0038] Protective Groups for Removal by PAC Catalysis
[0039] The fluorine-containing copolymers of the resist compositions of this invention can contain one or more components having protected acidic fluorinated alcohol groups (e.g., —C(R f )(R f ′)OR a , where R a is not H) or other acid groups that can yield hydrophilic groups by the reaction with acids or bases generated photolytically from photoactive compounds (PACs). A given protected fluorinated alcohol group contains a protecting group that protects the fluorinated alcohol group from exhibiting its acidity while in this protected form. A given protected acid group (R a ) is normally chosen on the basis of its being acid-labile, such that when acid is produced upon imagewise exposure, it will catalyze deprotection of the protected acidic fluorinated alcohol groups and production of hydrophilic acid groups that are necessary for development under aqueous conditions. In addition, the fluorine-containing copolymers may also contain acid functionality that is not protected (e.g., —C(R f )(R f ′)OR a , where R a ═H).
[0040] An alpha-alkoxyalkyl ether group (i.e., R a ═OR b , R b ═C 1 -C 11 alkyl) is a preferred protecting group for the fluoroalcohol group in order to maintain a high degree of transparency in the photoresist composition. An illustrative, but non-limiting, example of an alpha-alkoxyalkyl ether group that is effective as a protecting group, is methoxy methyl ether (MOM). A protected fluoroalcohol with this particular protecting group can be obtained by reaction of chloromethylmethyl ether with the fluoroalcohol. An especially preferred protected fluoroalcohol group has the structure:
—C(R f )(R f ′)O—CH 2 OCH 2 R 5
wherein, R f and R f ′ are the same or different fluoroalkyl groups of from 1 to 10 carbon atoms or taken together are (CF 2 ) n wherein n is 2 to 10; R 5 is H, a linear alkyl group of 1 to 10 carbon atoms, or a branched alkyl group of 3 to 10 carbon atoms.
[0042] Carbonates formed from a fluorinated alcohol and a tertiary aliphatic alcohol can also be used as protected acidic fluorinated alcohol groups.
[0043] The fluorine-containing copolymers of this invention can also contain other types of protected acidic groups that yield an acidic group upon exposure to acid. Examples of such types of protected acidic groups include, but are not limited to: A) esters capable of forming, or rearranging to, a tertiary cation; B) esters of lactones; C) acetal esters; D) β-cyclic ketone esters; E) α-cyclic ether esters; and F) esters which are easily hydrolyzable because of anchimeric assistance, such as MEEMA (methoxy ethoxy ethyl methacrylate).
[0044] Some specific examples in category A) are t-butyl ester, 2-methyl-2-adamantyl ester, and isobornyl ester.
[0045] In this invention, often, but not always, the components having protected groups are repeat units having protected acid groups that have been incorporated in the base copolymer resins of the compositions (as discussed above). Frequently the protected acid groups are present in one or more comonomers that are polymerized to form a given copolymeric base resin of this invention. Alternatively, in this invention, a copolymeric base resin can be formed by copolymerization with an acid- containing comonomer and then subsequently acid functionality in the resulting acid-containing copolymer can be partially or wholly converted by appropriate means to derivatives having protected acid groups.
[0046] Photoactive Component (PAC)
[0047] The polymers of this invention can be used to make photoresists by combining the copolymers with at least one photoactive component (PAC), a compound that affords either acid or base upon exposure to actinic radiation. If an acid is produced upon exposure to actinic radiation, the PAC is termed a photoacid generator (PAG). If a base is produced upon exposure to actinic radiation, the PAC is termed a photobase generator (PBG). Several suitable photoacid generators are disclosed in WO 00/66575.
[0048] Dissolution Inhibitors and Additives
[0049] Various dissolution inhibitors can be added to photoresists derived from the copolymers of this invention. Ideally, dissolution inhibitors (DIs) for far and extreme UV resists (e.g., 193 nm resists) should be designed/chosen to satisfy multiple materials needs including dissolution inhibition, plasma etch resistance, and adhesion behavior of resist compositions comprising a given DI additive. Some dissolution inhibiting compounds also serve as plasticizers in resist compositions. Several suitable dissolution inhibitors are disclosed in WO 00/66575.
[0050] Positive-Working and Negative-Working Photoresists
[0051] The photoresists derived from the copolymers of this invention can either be positive- or negative-working photoresists, depending upon choice of components in the fluoropolymer, the presence or absence of optional dissolution inhibitor and crosslinking agents, and the choice of solvent used in development.
[0052] Other Components
[0053] Photoresists derived from copolymers of this invention can contain additional optional components. Examples of optional components include, but are not limited to, resolution enhancers, adhesion promoters, residue reducers, coating aids, plasticizers, and T g (glass transition temperature) modifiers.
GLOSSARY Analytical/Measurements bs broad singlet δ NMR chemical shift measured in the indicated solvent g gram NMR Nuclear Magnetic Resonance 1 H NMR Proton NMR 13 C NMR Carbon-13 NMR 19 F NMR Fluorine-19 NMR s singlet sec. second(s) m multiplet mL milliliter(s) mm millimeter(s) T g Glass Transition Temperature M n Number-average molecular weight of a given polymer M w Weight-average molecular weight of a given polymer P = M w /M n Polydispersity of a given polymer Absorption coefficient AC = A/b, where A, absorbance, = Log 10 (1/T) and b = film thickness in microns, where T = transmittance as defined below. Transmittance Transmittance, T, = ratio of the radiant power transmitted by a sample to the radiant power incident on the sample and is measured for a specified wavelength λ (e.g., nm). Chemicals/Monomers DMF Dimethylformamide HFIBO Hexafluoroisobutylene epoxide 2HEtA 2-Hydroxyethyl acrylate Aldrich Chemical Company, Milwaukee, WI NBE Norbornene Aldrich Chemical Co., Milwaukee, WI Perkadox ® 16 N Di-(4-tert-butylcyclohexyl)peroxydicarbonate Noury Chemical Corp., Burt, NY Solkane 365 mfc 1,1,1,3,3-Pentafluorobutane Solvay Fluor, Hannover, Germany t-BuAc tert-Butyl acrylate Aldrich Chemical Company, Milwaukee, WI TCB Trichlorobenzene Aldrich Chemical Co., Milwaukee, WI TFE Tetrafluoroethylene E.I. du Pont de Nemours and Company, Wilmington, DE TFEtA 2,2,2-Trifluoroethyl acrylate Aldrich Chemical Company, Milwaukee, WI THF Tetrahydrofuran Aldrich Chemical Co., Milwaukee, WI Vazo ®52 2,4-Dimethyl-2,2′-azobis(pentanenitrile) E.I. DuPont de Nemours & Company, Wilmington, DE NB-F-OH X═OCH 2 C(CF 3 ) 2 OH Ultraviolet Extreme UV Region of the electromagnetic spectrum, in the ultraviolet that ranges from 10 nanometers to 200 nanometers Far UV Region of the electromagnetic spectrum in the ultraviolet that ranges from 200 nanometers to 300 nanometers UV Ultraviolet region of the electromagnetic spectrum which ranges from 10 nanometers to 390 nanometers Near UV Region of the electromagnetic spectrum in the ultraviolet that ranges from 300 nanometers to 390 nanometers
EXAMPLES
[0054] Unless otherwise specified, all temperatures are in degrees Celsius, all mass measurements are in grams, and all percentages are weight percentages.
[0055] Glass transition temperatures (T g ) were determined by DSC (differential scanning calorimetry) using a heating rate of 20° C./min, data is reported from the second heat. The DSC unit used is a Model DSC2910 made by TA Instruments, Wilmington, Del.
[0056] Assessment of 157 nm imaging sensitivity was done using a Lambda-Physik Compex 102 excimer laser configured for 157 nm operation. Vacuum ultraviolet transmission measurements were made using a McPherson spectrometer equipped with a D2 light source. Samples were spin-coated at several thicknesses on CaF 2 substrates, and the contribution of the substrate to the transmission was approximately removed by spectral division.
[0057] More specifically, all absorption coefficient measurements for polymers were made using the procedure listed below.
[0058] 1. Samples were first spin-coated on silicon wafers on a Brewer Cee (Rolla, Mo.), Spincoater/Hotplate model 100CB.
a) Two to four silicon wafers were spun at different speeds (e.g., 2000, 3000, 4000, 6000 rpm) to obtain differing film thickness and the coated wafers were subsequently baked at 120° C. for 30 min. The dried films were then measured for thickness on a Gaertner Scientific (Chicago, Ill.), L116A Ellipsometer (400 to 1200 angstrom range). Two spin speeds were then selected from this data to spin the CaF 2 substrates for the spectrometer measurement. b) Two CaF 2 substrates (1″ dia.×0.80″ thick) were selected and each was run as a reference data file on a McPherson Spectrometer (Chemsford, Ma.), 234/302 monochrometer, using a 632 Deuterium Source, 658 photomultiplier, and Keithley 485 picoammeter. c) Two speeds were selected from the silicon wafer data a) to spin the sample material onto the CaF 2 reference substrates (e.g., 2000 and 4000 rpm) to achieve the desired film thickness. Then each was baked at 120° C. for 30 min. and the sample spectra was collected on the McPherson Spectrometer; the sample files were then divided by the reference CaF 2 files. d) The resulting absorbance files were then adjusted (sample film on CaF 2 divided by CaF 2 blank) for film thickness to give absorbance per micron (abs/mic), which was done using GRAMS386 and KALEIDAGRAPH software.
Example 1
Synthesis of NB—F—OH
[0063] A dry round bottom flask equipped with mechanical stirrer, addition funnel and nitrogen inlet was swept with nitrogen and charged with 19.7 g (0.78 mol) of 95% sodium hydride and 500 mL of anhydrous DMF. The stirred mixture was cooled to 5° C. and 80.1 g (0.728 mol) of exo-5-norbornen-2-ol was added dropwise so that the temperature remained below 15° C. The resulting mixture was stirred for 0.5 hr. HFIBO (131 g, 0.728 mol) was added dropwise at room temperature. The resulting mixture was stirred overnight at room temperature. Methanol (40 mL) was added and most of the DMF was removed on a rotary evaporator under reduced pressure. The residue was treated with 200 mL water, and glacial acetic acid was added until the pH was about 8.0. The aqueous mixture was extracted with 3×150 mL ether. The combined ether extracts were washed with 3×150 mL water and 150 mL brine, dried over anhydrous sodium sulfate, and concentrated on a rotary evaporator to an oil. Kugelrohr distillation at 0.15-0.20 torr and a pot temperature of 30-60° C. gave 190.1 (90%) of product. 1 H NMR (δ, CD 2 Cl 2 ) 1.10-1.30 (m, 1H), 1.50 (d, 1H), 1.55-1.65 (m, 1H), 1.70 (s, 1H), 1.75 (d, 1H), 2.70 (s, 1H), 2.85 (s, 1H), 3.90 (d, 1H), 5.95 (s, 1H), 6.25 (s, 1H). Another sample prepared in the same fashion was submitted for elemental analysis. Calcd. for C 11 H 12 F 6 O 2 : C, 45.53; H, 4.17; F, 39.28. Found: C, 44.98; H, 4.22; F, 38.25.
Example 2
Polymer of TFE, NB—F—OH, t-BuAc and 2HEtA
[0064] A metal pressure vessel of approximate 270 mL capacity was charged with 70.33 g NB—F—OH, 0.64 g tert-butyl acrylate, 0.29 g 2HEtA and 25 mL Solkane 365. The vessel was closed, cooled to about −15° C. and pressured to 400 psig with nitrogen and vented several times. The reactor contents were heated to 50° C. TFE was added to a pressure of 340 psig and a pressure regulator was set to maintain the pressure at 340 psig throughout the polymerization by adding TFE as required. A solution of 80.56 g of NB—F—OH, 6.22 g of tert-butyl acrylate and 2.42 g 2HEtA diluted to 100 mL with Solkane 365 mfc was pumped into the reactor at a rate of 0.10 mL/minute for 12 hr. Simultaneously with the monomer feed solution, a solution of 6.3 g Perkadox®16N and 45 mL methyl acetate diluted to 75 mL with Solkane 365 mfc was pumped into the reactor at a rate of 2.0 mL/minute for 6 minutes, and then at a rate of 0.08 mL/minute for 8 hours. After 16 hours reaction time, the vessel was cooled to room temperature and vented to 1 atmosphere. The recovered polymer solution was added slowly to an excess of hexane while stirring. The precipitate was filtered, washed with hexane and air-dried. The resulting solid was dissolved in a mixture of THF and Solkane 365 mfc and added slowly to excess hexane. The precipitate was filtered, washed with hexane and dried in a vacuum oven overnight to give 56.1 g of white polymer. From its 13 C NMR spectrum, the polymer composition was found to be 35% TFE, 42% NB—F—OH, 18% t-BuAc and 5% 2HEtA. DSC: Tg=134° C. GPC: Mn=5400; Mw=9100; Mw/Mn=1.67. Anal. Found: C, 44.74; H; 4.17; F; 38.79.
Example 3
Polymer of TFE, NB—F—OH, t-BuAc and 2HEtA
[0065] The procedure of Example 2 was followed except 70.33 g NB—F—OH, 0.85 g tert-butyl acrylate, 0.096 g 2HEtA and 25 mL Solkane 365 were initially placed in the vessel. A solution of 78.55 g of NB—F—OH, 8.71 g of tert-butyl acrylate, and 0.97 g 2HEtA diluted to 100 mL with Solkane 365 mfc was pumped into the reactor during the polymerization at a rate of 0.10 mL/minute for 12 hr. Simultaneously with the monomer feed solution, a solution of 7.3 g Perkadox®16N and 60 mL methyl acetate diluted to 100 mL with Solkane 365 mfc was pumped into the reactor at a rate of 2.0 mL/minute for 6 minutes, and then at a rate of 0.1 mL/minute for 8 hours. After 16 hours reaction time, the vessel was cooled to room temperature and vented to 1 atmosphere. The recovered polymer solution was added slowly to an excess of heptane while stirring. The precipitate was filtered, washed with heptane and air-dried. The resulting solid was dissolved in a mixture of THF and Solkane 365 mfc and added slowly to excess heptane. The precipitate was filtered, washed with heptane and dried in a vacuum oven overnight to give 46.4 g of white polymer. From its 13 C NMR spectrum, the polymer composition was found to be 33% TFE, 46% NB—F—OH, 16% t-BuAc and 5% 2HEtA. DSC: Tg=145° C. GPC: Mn=5300; Mw=8400; Mw/Mn 1.57. Anal. Found: C, 45.51; H, 4.35; F, 37.28.
Example 4
Polymer of TFE, NB—F—OH, t-BuAc and 2HEtA
[0066] The procedure of Example 2 was followed except 68.15 g NB—F—OH, 1.76 g tert-butyl acrylate, 0.145 g 2HEtA and 25 mL Solkane 365 were initially placed in the vessel. A solution of 70.49 g of NB—F—OH, 12.13 g of tert-butyl acrylate and 1.09 g 2HEtA diluted to 100 mL with Solkane 365 mfc was pumped into the reactor during the polymerization at a rate of 0.10 mL/minute for 12 hr. Simultaneously with the monomer feed solution, a solution of 7.3 g Perkadox®16N and 60 mL methyl acetate diluted to 100 mL with Solkane 365 mfc was pumped into the reactor at a rate of 2.0 mL/minute for 6 minutes, and then at a rate of 0.1 mL/minute for 8 hours. After 16 hours reaction time, the vessel was cooled to room temperature and vented to 1 atmosphere. The recovered polymer solution was added slowly to an excess of heptane while stirring. The precipitate was filtered, washed with heptane and air-dried. The resulting solid was dissolved in a mixture of THF and Solkane 365 mfc and added slowly to excess heptane. The precipitate was filtered, washed with heptane and dried in a vacuum oven overnight to give 49 g of white polymer. From its 13 C NMR spectrum, the polymer composition was found to be 28% TFE, 35% NB—F—OH, 30% t-BuAc and 6% 2HEtA. DSC: Tg=150° C. GPC: Mn=6000; Mw=11000; Mw/Mn=1.82. Anal. Found: C, 46.42; H, 4.28; F, 36.13.
Example 5
Polymer of TFE, NB—F—OH, t-BuAc and 2HEtA
[0067] A metal pressure vessel of approximate 1 L capacity was charged with 206.63 g NB—F—OH, 3.84 g tert-butyl acrylate, 0.87 g 2HEtA and 75 mL Solkane 365. The vessel was closed, cooled to about −15° C. and pressured to 400 psig with nitrogen and vented several times. The reactor contents were heated to 50° C. TFE was added to a pressure of 320 psig and a pressure regulator was set to maintain the pressure at 320 psig throughout the polymerization by adding TFE as required. A solution of 202.28 g of NB—F—OH, 23.81 g of tert-butyl acrylate and 5.39 g 2HEtA diluted to 250 mL with Solkane 365 mfc was pumped into the reactor at a rate of 0.28 mL/minute for 12 hr. Simultaneously with the monomer feed solution, a solution of 18.45 g Perkadox®16N and 100 mL methyl acetate diluted to 200 mL with Solkane 365 mfc was pumped into the reactor at a rate of 6.0 mL/minute for 6 minutes, and then at a rate of 0.24 mL/minute for 8 hours. After 16 hours reaction time, the vessel was cooled to room temperature and vented to 1 atmosphere. The recovered polymer solution was added slowly to an excess of heptane while stirring. The precipitate was filtered, washed with heptane and air-dried. The resulting solid was dissolved in a mixture of THF and Solkane 365 mfc and added slowly to excess heptane. The precipitate was filtered, washed with heptane and dried in a vacuum oven overnight to give 156.2 g of white polymer. From its 13 C NMR spectrum, the polymer composition was found to be 31% TFE, 44% NB—F—OH, 21% t-BuAc and 3% 2HEtA. DSC: Tg=139° C. GPC: Mn=4200; Mw=8000; Mw/Mn=1.87. Anal. Found: C, 45.92; H, 4.23; F, 36.83.
Example 6
Polymer of TFE, NB—F—OH, t-BuAc and TFEtA
[0068] The procedure of Example 2 was followed except 70.33 g NB—F—OH, 0.64 g tert-butyl acrylate, 0.39 g TFEtA and 25 mL Solkane 365 was initially placed in the vessel. A solution of 80.56 g of NB—F—OH, 6.22 g of tert-butyl acrylate and 3.21 g TFEtA diluted to 100 mL with Solkane 365 mfc was pumped into the reactor during the polymerization at a rate of 0.10 mL/minute for 12 hr. Simultaneously with the monomer feed solution, a solution of 6.3 g Perkadox®16N and 45 mL methyl acetate diluted to 75 mL with Solkane 365 mfc was pumped into the reactor at a rate of 2.0 mL/minute for 6 minutes, and then at a rate of 0.08 mL/minute for 8 hours. After 16 hours reaction time, the vessel was cooled to room temperature and vented to 1 atmosphere. The recovered polymer solution was added slowly to an excess of hexane while stirring. The precipitate was filtered, washed with hexane and air-dried. The resulting solid was dissolved in a mixture of THF and Solkane 365 mfc and added slowly to excess hexane. The precipitate was filtered, washed with hexane and dried in a vacuum oven overnight to give 52.34 g of white polymer. From its 13 C NMR spectrum, the polymer composition was found to be 36% TFE, 41% NB—F—OH, 19% t-BuAc and 4% TFEtA. DSC: Tg=136° C. GPC: Mn=5800; Mw=9300; Mw/Mn=1.59. Anal. Found: C, 44.39; H, 3.94; F, 39.96.
Example 7
Polymer of TFE, NB—F—OH, t-BuAc and TFEtA
[0069] A metal pressure vessel of approximate 270 mL capacity was charged with 70.33 g NB—F—OH, 0.85 g tert-butyl acrylate, 0.13 g TFEtA and 25 mL Solkane 365. The vessel was closed, cooled to about −15° C. and pressured to 400 psig with nitrogen and vented several times. The reactor contents were heated to 50° C. TFE was added to a pressure of 340 psig and a pressure regulator was set to maintain the pressure at 340 psig throughout the polymerization by adding TFE as required. A solution of 78.54 g of NB—F—OH, 8.71 g of tert-butyl acrylate and 1.28 g TFEtA diluted to 100 mL with Solkane 365 mfc was pumped into the reactor at a rate of 0.10 mL/minute for 12 hr. Simultaneously with the monomer feed solution, a solution of 7.3 g Perkadox®16N and 60 mL methyl acetate diluted to 100 mL with Solkane 365 mfc was pumped into the reactor at a rate of 2.0 mL/minute for 6 minutes, and then at a rate of 0.1 mL/minute for 8 hours. After 16 hours reaction time, the vessel was cooled to room temperature and vented to 1 atmosphere. The recovered polymer solution was added slowly to an excess of hexane while stirring. The precipitate was filtered, washed with hexane and air-dried. The resulting solid was dissolved in a mixture of THF and Solkane 365 mfc and added slowly to excess to hexane. The precipitate was filtered, washed with hexane and dried in a vacuum oven overnight to give 55.4 g of white polymer. From its 13 C NMR spectrum, the polymer composition was found to be 33% TFE, 44% NB—F—OH, 19% t-BuAc and 3% TFEtA. DSC: Tg=138° C. GPC: Mn=5300; Mw=8400; Mw/Mn1.59. Anal. Found: C, 44.98; H, 4.21; F, 38.80.
Example 8
Polymer of TFE, NB—F—OH, t-BuAc and TFEtA
[0070] The procedure of Example 7 was followed except 68.88 g NB—F—OH, 1.15 g tert-butyl acrylate, 0.55 g TFEtA and 25 mL Solkane 365 were initially placed in the vessel. TFE was added to a pressure of 320 psig and a pressure regulator was set to maintain the pressure at 320 psig throughout the polymerization by adding TFE as required. A solution of 75.52 g of NB—F—OH, 8.00 g of tert-butyl acrylate and 3.74 g TFEtA diluted to 100 mL with Solkane 365 mfc was pumped into the reactor during the polymerization at a rate of 0.10 mL/minute for 12 hr. Simultaneously with the monomer feed solution, a solution of 7.3 g Perkadox®16N and 60 mL methyl acetate diluted to 100 mL with Solkane 365 mfc was pumped into the reactor at a rate of 2.0 mL/minute for 6 minutes, and then at a rate of 0.1 mL/minute for 8 hours. After 16 hours reaction time, the vessel was cooled to room temperature and vented to 1 atmosphere. The recovered polymer solution was added slowly to an excess of hexane while stirring. The precipitate was filtered, washed with hexane and air-dried. The resulting solid was dissolved in a mixture of THF and Solkane 365 mfc and added slowly to excess hexane. The precipitate was filtered, washed with hexane and dried in a vacuum oven overnight to give 51.3 g of white polymer. From its 13 C NMR spectrum, the polymer composition was found to be 31% TFE, 41% NB—F—OH, 20% t-BuAc and 7% TFEtA. DSC: Tg=140° C. GPC: Mn=4300; Mw=8500; Mw/Mn=1.98. Anal. Found: C, 45.11; H, 4.05; F, 38.30.
Example 9
Imaging of Polymer of TFE, NB—F—OH, t-BuAc, and 2HEtA
[0071] The following solution was prepared, magnetically stirred overnight, and filtered through a 0.45 μm PTFE syringe filter before use:
Component Wt. (gm) TFE/NB-F-OH/t-BuAc/2HEtA Polymer from 1.507 Example 5 2-Heptanone 10.715 6.82% (wt) solution of triphenylsulfonium nonaflate 0.778 dissolved in cyclohexanone which had been filtered through a 0.45 μm PTFE syringe filter.
[0072] This resist formulation was spin cast on an 8 inch Si wafer at a speed of 1992 rpm, yielding a film of measured thickness 2125 Å after PAB at 150° C. for 60 sec. This film was then exposed to 157 nm radiation in the Exitech stepper using a phase shift mask to yield a latent image. After exposure, the film was post-exposure baked at 105° C. for 60 sec, and then puddle developed at 60 sec at room temperature using the tetramethyl ammonium hydroxide developer. The resulting image was examined using a JEOL 7550 SEM. At an exposure dose of 13 mJ/cm 2 , the image was found to exhibit features at 80 nm resolution.
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Fluorinated copolymers useful in photoresist compositions and associated processes for microlithography are described. These copolymers are comprised of a fluoroalcohol or protected fluoroalcohol functional group which simultaneously imparts high ultraviolet (UV) transparency and developability in basic media to these materials and a repeat unit derived from an acrylate monomer containing a fluoroalkyl group or a hydroxyl substituted alkyl group. The materials of this invention have high UV transparency, particularly at 193 and 157 nm, which makes them highly useful for lithography at these short wavelengths.
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BACKGROUND INFORMATION
Interactive Voice Response Systems (IVRs), Automated Call Distribution (ACD) Systems, Voice Portals and other telecommunications interaction and management systems are increasingly used to provide services for clients, employees and other users. Such systems may frequently be communicatively coupled to one phone or data network and may be communicatively coupled to other networks by a gateway. For example, an Interactive Voice Response (IVR) System of a service provider may be communicatively coupled to an Internet Protocol (IP) based network and may be communicatively coupled to one or more circuit switched networks via one or more gateways. The IVR System may receive a call to be transferred across a gateway via a trunk to a destination number. The IVR System may not know the type of a trunk to be used for the destination call. Different types of trunks may require different call signaling mechanisms. Thus, some IVR Systems may not be able to transfer calls to some trunks and may use work around mechanisms such as the gateway initiating a second call and conferencing the two calls together. The inability to transfer a call may lead to the use of additional connections and may require a call to continue the use of Interactive Voice Response (IVR) System resources and/or gateway resources as the call may be routed through these resources instead of transferred off of them.
Furthermore, a gateway may be capable of utilizing two or more different types of trunks. IVR Systems, ACD Systems, Voice Portals and other telecommunications interaction and management systems, however, may not have information about the type of trunk to be used for the destination call. These Automated Call Distribution (ACD) Systems, Voice Portals or other telecommunications interaction and management system may attempt to transfer a call to a destination number in a format compatible for a first type of trunk but the transfer may fail if the trunk used is a second type of trunk. For example, a first type of trunk may use two channels: a data or bearer channel and a control channel. A second type of trunk may use a single channel with in-band signaling, such as one or more dual-tone multi-frequency (DTMF) tones. A gateway may receive the call and may know how to transfer the call to a first type of trunk with two channels but may not know how to transfer to a second type of trunk using in-band signaling. Thus if the call is destined for the second type of trunk requiring in-band signaling, the call may be dropped. Accordingly, gateways may be incapable of transferring a call to a call destination back on an originating network or other network, such as a circuit switched telephone network.
BRIEF DESCRIPTION OF THE DRAWINGS
In order to facilitate a fuller understanding of the exemplary embodiments, reference is now made to the appended drawings. These drawings should not be construed as limiting, but are intended to be exemplary only.
FIG. 1 is a schematic of a trunk independent gateway transfer system, in accordance with an exemplary embodiment;
FIG. 2 , depicts a block diagram of a gateway transfer module for a trunk independent gateway transfer system, in accordance with an exemplary embodiment; and
FIG. 3 depicts a flow chart for a method for implementing a trunk independent gateway transfer system, in accordance with an exemplary embodiment.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. It should be appreciated that the same reference numbers will be used throughout the drawings to refer to the same or like parts. It should be appreciated that the following detailed description are exemplary and explanatory only and are not restrictive.
An exemplary embodiment provides a trunk independent gateway transfer system to one or more networks. The trunk independent gateway transfer system may present improved call handling for one or more users of the trunk independent gateway transfer system. For example, a trunk independent gateway system may enable the transfer of a call to one or more trunk types on a circuit switched network without requiring a transfer requesting system to be aware of the trunk type. This may enable the usage of a single format of call transfer request regardless of the type of trunk being used for a transferred call.
Referring to FIG. 1 , a trunk independent gateway transfer system in accordance with an exemplary embodiment is illustrated. System 100 illustrates an exemplary system for improving call handling at a gateway. It is noted that system 100 is a simplified view of a network and may include additional elements that are not depicted. As illustrated, the system 100 may include one or more networks, such as network 104 and network 108 . Networks 104 and 108 may be communicatively coupled to the gateway 106 via trunk 120 and trunk 122 . One or more telecommunication devices 102 a and 102 b may be communicatively coupled to networks 104 and 108 . Other network elements, such as network elements 110 , 112 , 114 , 116 , and 118 may be communicatively coupled to networks 104 and/or 108 .
The telecommunication devices 102 may be a wireline phone, a wireless phone, a satellite phone, Personal Digital Assistant (PDA), computer, or other telecommunications enabled devices. The telecommunication devices 102 may be communicatively coupled to the network 104 and 108 . The telecommunication devices 102 and network elements 110 , 112 , 114 , 116 and 118 may send and receive data using one or more protocols. For example, data may be transmitted and/or received using Wireless Application Protocol (WAP), Multimedia Messaging Service (MMS), Enhanced Messaging Service (EMS), Short Message Service (SMS), Global System for Mobile Communications (GSM) based systems, Time Division Multiplexing (TDM) based systems, Code Division Multiple Access (CDMA) based systems, Transmission Control Protocol/Internet (TCP/IP) Protocols, or other protocols and/or systems suitable for transmitting and receiving data. Data may be transmitted and/or received wirelessly or may use cabled network connections or telecom connections such as an Ethernet RJ45/Category 5 Ethernet connection, a fiber connection, a traditional phone wireline connection, a cable connection or other wired network connection. Network elements 110 , 112 , 114 , 116 , and 118 may use standard wireless protocols including IEEE 802.11a, 802.11b and 802.11g. Network elements 110 , 112 , 114 , 116 , and 118 may also be communicatively coupled via protocols for a wired connection, such as an IEEE Ethernet 802.3.
Networks 104 and 108 may be local area networks (LAN), wide area networks (WAN), the Internet, a Public Switched Telephone Network (PSTN), cellular networks, satellite networks, or other networks that permit that transfer and/or reception of data.
Network elements 110 , 112 , 114 , 116 , and 118 may each be one or more servers (or server-like devices), such as a Session Initiation Protocol (SIP) server. Network elements 110 , 112 , 114 , 116 , and 118 may be telecom switches, Private Branch Exchanges (PBXs), Voice Response Units (VRUs), announcement servers, voice mail servers and/or voice portals. Network elements 110 , 112 , 114 , 116 , and 118 may be VoIP (Voice Over Internet Protocol) enabled devices. Network elements 110 , 112 , 114 , 116 , and 118 may include one or more processors (not shown) for recording, transmitting, receiving, and/or storing data. Although network elements 110 , 112 , 114 , 116 , and 118 are depicted as individual servers, it should be appreciated that the contents of network elements 110 , 112 , 114 , 116 , and 118 may be combined into fewer or greater numbers of servers (or server-like devices) and may be connected to one or more data storage systems (not shown). Data storage systems may be local or remote to network elements 110 , 112 , 114 , 116 , and 118 .
The gateway 106 may be a media gateway interconnecting two or more networks. For example, the gateway 106 may enable the routing of calls and other data between a first network 104 and a second network 108 . The gateway 106 may include one or more processors, such as processor 124 , to enable routing determinations and other determinations. The gateway 106 may contain or be communicatively coupled to other components (not shown) such as storage, memory, and/or one or more interfaces. The gateway 106 may enable the routing of calls between different network types such as between a circuit switched network and a packet switched network. In one or more embodiments, the gateway 106 may be replaced by a switch (not shown) connecting two IP networks. In other embodiments, the gateway 106 may be replaced by a switch (not shown) connecting two circuit switched networks. In some embodiments, the gateway 106 may be replaced by a switch (not shown) connecting two portions of the same network. Although network 108 is depicted as having a single gateway 106 communicatively coupled to two trunks, in one or more embodiments, a plurality of gateways may be connected to network 108 each containing one or more trunks.
In one or more embodiments, network 104 may represent a circuit switched network and network 108 may be a IP based network. Gateway 106 may receive one or more call transfer requests from one or more network elements communicatively coupled to network 108 . For example, network element 114 may be an Interactive Voice Response System (IVR), an Automated Call Distribution (ACD) System, a Voice Portal or other telecommunications interaction and management system. Out-of band signaling trunk 122 may be a trunk utilizing Two B Channel Transfer (TBCT) or other out of band signaling mechanisms for one or more call transfers. In-band signaling trunk 120 may be a trunk utilizing in-band call signaling. Network element 114 may receive a call from a user at telecommunications device 102 a . Network element 114 may make a determination to transfer a call to network element 110 , a Private Branch Exchange (PBX) associated with a call center, via trunk 120 . Network element 110 may not have a way to determine the type of a trunk. Gateway 106 upon receipt of a call transfer request may identify the trunk to be used for routing the call. After identifying the trunk, gateway 106 may determine the type of trunk to be used. Depending on the type of trunk, gateway 106 , may facilitate in-band and/or out-of-band signaling to complete the call transfer. In the above example, trunk 120 may be a trunk utilizing in-band signaling such as the use of one or more dual-tone multi-frequency (DTMF) tones. Gateway 106 may generate, download, receive, and/or concatenate one or more tones for use with in-band signaling.
In one or more embodiments, gateway 106 may receive destination information from a call transfer request. Gateway 106 may parse a call transfer request to determine a call destination, a trunk to use and/or other information. For example, network 108 may be a network utilizing Session Initiation Protocol (SIP). Gateway 106 may receive a call transfer request as a Session Initiation Protocol (SIP) refer message (e.g., a call transfer request compliant with RFC 3515). The Session Initiation Protocol (SIP) refer message may contain routing information used by the gateway to transfer the call. Gateway 106 may then generate transfer information such as in-band signaling to transfer the call for trunks utilizing in-band signaling. If a call is to be transferred to a trunk utilizing a secondary or D (data) channel for signaling, gateway 106 may generate, request, receive or otherwise obtain the appropriate out-of-band control signaling to transfer the call.
In one or more embodiments, a gateway, such as gateway 106 , may associate an application with a trunk. When a call is routed for a trunk, the application may be initiated and may use one or more parameters which may be provided by the gateway. For example, gateway 106 may contain a trunk group (not shown) associated with a trunk. Associated with the trunk group may be another logical subdivision, such as dial pairs. An application may be associated with the dial pairs, such that a call destined for the portion of the trunk associated with the dial pairs initiates the application. For example, a Tool Command Language (TCL) script may be used. The TCL script may parse one or more transfer requests, such as a SIP refer message received from an IVR system, and may use routing information contained in the transfer request to generate transfer information.
In one or more embodiments, gateway 106 may determine transfer information utilizing Dialed Number Identification Service (DNIS) information associated with a call, a lookup table, an array, a database, an interface to a local or remote system, mapping rules or other mapping methods. For example, if a transfer request is received and contains incomplete, incorrect, or no information to generate the transfer, gateway 106 may map the call to a destination. In one or more embodiments, gateway 106 may use a default location based on a transfer requester. As an example, gateway 106 may receive a call transfer request from network element 114 , which may be an IVR system. Gateway 106 may route one or more calls received from network element 114 to network element 110 and may generate the corresponding transfer information. In one or more embodiments, gateway 106 may lookup transfer information utilizing information, such as DNIS information associated with the call being transferred.
The various components of the system 100 as shown in FIG. 1 may be further duplicated, combined and/or integrated to support various applications and platforms. Additional elements may also be implemented in the systems described above to support various applications.
Referring to FIG. 2 , a gateway transfer module 210 for improved gateway call handling is depicted, in accordance with an exemplary embodiment. As illustrated, the gateway transfer module 210 may contain one or more components including a gateway monitoring module 212 , a call mapping module 214 , a call transfer module 216 , and an error handling module 218 . The gateway transfer module 210 may improve call handling for transfer requests.
The gateway monitoring module 212 may monitor calls to determine if they meet one or more conditions. The gateway monitoring module 212 may identify transfer requests or failed transfer calls. The gateway monitoring module 212 may identify to the call mapping module 214 call requests that require a transfer or failed transfer calls.
The call mapping module 214 may use information in a call transfer request to determine call destination information. For example, a call transfer request may be a SIP refer request which may contain call destination information to be parsed by the call mapping module 214 . In one or more embodiments, the call mapping module 214 may receive one or more call attributes or DNIS information associated with a call. The call mapping module 214 may use call attributes, DNIS information, or other information to query a lookup table, an array, a database, an interface to a local or remote system, mapping rules or other mapping methods to determine one or more call destinations. Mapping rules or logic may use a time of day, a call origination geographic location, a call destination geographic location, a load or utilization of an alternate call destination, caller information associated with a call, priority information associated with a call, or other factors to determine one or more call destinations. In some embodiments, the call mapping module 214 may provide one or more default call destinations. Once a call destination is identified, the call transfer module 216 may be used to transfer the call.
The call transfer module 216 may receive one or more alternate call destinations from the call mapping module 214 . The call transfer module 216 may identify a trunk to be used for a call destination and may determine if one or more actions should be taken to transfer the call. The call transfer module 216 may reside on a gateway or may query a gateway to determine a trunk and/or a trunk type. The gateway may identify the trunk based on the call destination. The call transfer module 216 may identify a type of trunk and a corresponding control signaling format used for the type of trunk. For example, the call transfer module 216 may determine that trunk 120 may be a trunk utilizing in-band signaling such as the use of one or more dual-tone multi-frequency (DTMF) tones. The call transfer module 216 may then generate, download, receive, and/or concatenate one or more tones for use in in-band signaling. The call transfer module 216 may concatenate audio files to provide a single audio file enabling the playing of the audio file to generate a transfer. The call transfer module 216 may then play the tones on the trunk to complete the transfer. In other examples, other techniques, such as Session Initiation Protocol (SIP) call signaling and setup techniques may be used. In one or more embodiments, call transfer module 216 may cancel an original transfer and transfer the a call to an alternate call destination (e.g., perform a “take back and transfer.”)
In one or more embodiments, the call transfer module 216 may determine that a trunk, such as trunk 122 , uses a secondary or D (data) channel for signaling. The call transfer module 216 may generate, request, receive or otherwise obtain the appropriate out-of-band control signaling to transfer the call.
In one or more embodiments, a gateway and/or an application residing on a gateway may accept a single format of transfer request from an TVR System, an ACD System, a Voice Portal and/or other telecommunications interaction and management systems. This may enable such systems to request a transfer call without knowledge of the type of trunk to be used or its respective signaling and/or communication requirements. Enabling call transfer to a plurality of trunk types using a uniform transfer request type may reduce complexity and overhead in connections between networks, such as between IP based networks and circuit switched networks. A uniform transfer request type may also reduce dropped calls and other errors. A uniform transfer request format may reduce the need for conferencing multiple calls together. Enabling call transfers for a plurality of trunk types may reduce practices such as continuing to route calls through a gateway and/or an IVR System after the IVR System has completed its call handling and conferenced in a call destination. Call transferring may thus reduce traffic and wasted connections by enabling the transferred call to be routed more directly between the caller and the destination.
The error handling module 218 may respond to one or more errors associated with a call transfer request and/or a call transfer. The error handling module 218 may enable error trapping and one or more error handling actions. In some embodiments, the error handling module 218 may provide information about a failed network component such as the failure of one or more of network elements 110 , 112 , 114 , 116 , and/or 118 . The error handling module 218 may provide information about one or more call routing errors.
FIG. 3 depicts a flowchart of a method for implementing a gateway transfer system 300 , according to an exemplary embodiment. The exemplary method 300 is provided by way of example, as there are a variety of ways to carry out methods disclosed herein. The method 300 shown in FIG. 3 may be executed or otherwise performed by one or a combination of various systems. The method 300 is described below as carried out by the system 100 shown in FIG. 1 and the gateway transfer module 210 shown in FIG. 2 by way of example, and various elements of the FIGS. 1 and 2 are referenced in explaining exemplary method 300 of FIG. 3 , and various elements of FIG. 1 and FIG. 2 are referenced in explaining the exemplary method of FIG. 3 . Each block shown in FIG. 3 represents one or more processes, methods, or subroutines carried in the exemplary method 300 . A computer readable media comprising code to perform the acts of the method 300 may also be provided. Referring to FIG. 3 , the exemplary method 300 may begin at block 302 .
At block 304 , a call transfer request may be received at a gateway, such as gateway 106 . Some gateways may contain a single trunk associated with them and other gateways may contain a plurality of trunks.
At block 306 , a trunk may be identified to be used for routing the call. The type of the identified trunk may be determined. For example, gateway 106 may identify the type of trunk to be used based on the configuration of the trunk at the gateway.
At block 308 , the control signaling or other formatting used for a call transfer is identified. For example, an application or logic associated with gateway 106 may provide a mapping of trunk types to control signaling or other formatting used for a call transfer. In some embodiments, logic may be associated with each individual trunk of a gateway and may contain signaling information specific to that trunk. If the corresponding trunk type uses in-band signaling, such as trunk 120 , the method 300 may continue at block 314 . If corresponding trunk type uses out-of-band signaling, such as trunk 122 , the method may continue at block 310 .
At block 310 , a determination may be made as to whether a call transfer requires other preparation or generation of transfer information. The type of trunk, the type of gateway, the type of origin network, or other factors may determine whether generation of other transfer information is required. If additional call transfer preparation is required the method 300 may continue at block 312 . If no additional call transfer preparation is required the method 300 may continue at block 324 .
At block 312 , additional call transfer preparation may be performed. In one or more embodiments, data of a call transfer request may be parsed and out-of-band control signaling information may be generated. In one or more embodiments, gateway 106 and/or call mapping module 214 may parse a call transfer request to identify a call destination. Gateway 106 and/or call transfer module 216 may prepare call transfer signaling information. For example, the method may prepare call transfer signaling information for trunk 122 which may be a trunk utilizing Two B Channel Transfer (TBCT) or other out of band signaling mechanisms.
At block 314 , a determination may be made as to whether a call transfer request contains sufficient routing information to generate call transfer information. If the call transfer request contains sufficient routing information to generate call transfer information the method 300 may continue at block 322 . For example, an application running on gateway 106 may parse a call transfer request, which may be a SIP refer request. In some embodiments, if a call transfer request does not contain sufficient routing information, an error may be returned to the call transfer requestor (e.g., an IVR system or an ACD system). In one or more embodiments, if the call transfer request does not contain sufficient routing information to generate call transfer information the method 300 may continue at block 316 .
At block 316 , a determination may be made as to whether other routing information is available to handle a call transfer request. For example, a gateway, such as gateway 106 , may use a lookup table, an array, a database, an interface to a local or remote system, mapping rules or other mapping methods to determine one or more call destinations. If other routing information is available to handle a call transfer request, the method 300 may continue at block 318 . If other routing information is not available to handle a call transfer request, the method 300 may continue at block 320 .
At block 318 , routing tables, interfaces, call request attributes, call information (e.g., DNIS information), transfer requestor information, call origination information and/or logic may be used to obtain other call routing information. For example, gateway 106 may use attributes associated with a call, such as an originating phone number, to determine call routing information.
At block 320 , calls for which call routing information has not been identified may be dropped. In one or more embodiments, error messages may be returned to a call transfer requester and/or a call initiator. For example, if call routing information has not been identified a gateway may drop a call, play an error message to a caller (e.g., redirect a call to an announcement server (not shown)), or route a call to a default call handling center.
At block 322 , call transfer information may be generated. For example, gateway 106 and/or call transfer module 216 may generate transfer information. For calls routed on trunks utilizing in-band signaling, one or more DTMF tones may be generated. For calls routed on trunks utilizing in-band signaling, the in-band signaling may be stored as an audio file. For calls routed on trunks utilizing out-of-band signaling other control signaling information may be generated.
At block 324 , the call may be transferred. For example, gateway 106 may transmit signaling information generated as described in block 322 which may permit the call to be transferred.
At block 326 , the method may end.
In the preceding specification, various preferred embodiments have been described with reference to the accompanying drawings. It will, however, be evident that various modifications and changes may be made thereto, and additional embodiments may be implemented, without departing from the broader scope of the invention as set forth in the claims that follow. The specification and drawings are accordingly to be regarded in an illustrative rather than restrictive sense.
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Techniques for providing a method and system for trunk independent gateway transfer of calls are disclosed. In one particular exemplary embodiment, the techniques may be realized as a computer implemented method, comprising receiving a call transfer request for a call at a gateway and determining, using a processor of the gateway, whether a trunk to be used for transferring the call requires a transfer command. In the event the trunk requires transfer command, the techniques comprise generating a transfer command, and transferring the call using the transfer command.
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