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BACKGROUND OF THE INVENTION
The reason why vacuum contactors and vacuum interrupters are used for power switching applications is due to two fundamental properties of the vacuum medium.
First, the dielectric strength of a vacuum gap is far superior to any other switching medium (air in atmospheric pressure, oil, etc.). These properties enable the construction of small sized lightweight practical switching devices.
The tendency of the vacuum arc to cease to exist at low current (known as current chopping), a condition that exists every half cycle in alternating current systems, reduces the scope of application of vacuum switches to systems with low surge impedances (low inductive systems).
The stability of the vacuum arc depends only on the amount of metal vapor present in the gap between the contacts of the vacuum switch at arcing time. The metal vapor is supplied by the contact material. One way to increase the stability of the vacuum arc and reduce the current chopping level is to choose contact material with high vapor pressure. This choice has its limitations because a material with high vapor pressure tends to erode faster and it also might raise the pressure inside the vacuum switch and reduce the interruption capabilities of the device. The other way is to try to prevent the vapor from diffusing into the volume of the switch for a short period of time. This will increase the stability of the vacuum arc and at the same time would not reduce the interruption ability of the vacuum switch. My invention addresses itself to the latter choice. Vacuum means any pressure lower than the standard atmospheric pressure of 760 mm Hg.
Vacuum contactors for motor control applications have been known heretofore.
The vacuum contactor differs from the vacuum interrupter in that its lower voltage rating makes it possible to use a smaller volume. Also, the vacuum contactor has to repeat its function many more times than does the vacuum interrupter.
The requirement for repetitive operation calls for a bellows with a long life.
SUMMARY OF THE INVENTION
This invention relates to vacuum contactors and methods of making the same.
An object of the invention is to provide an improved vacuum contactor.
Another object of the invention is to provide an improved method of making a vacuum contactor.
A more specific object of the invention is to provide an improved vacuum contactor having a long life for motor control applications.
Another specific object of the invention is to provide an improved method of making a vacuum contactor allowing the use of welded diaphragm bellows therein of long life material and small size without sacrificing the long life thereof required for motor control applications.
Other objects and advantages of the invention will hereinafter appear.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view along the vertical axis of a first configuration of vacuum contactor designed for 100-200 ampere current range devices;
FIG. 2 is a cross-sectional view along the vertical axis of a second configuration of vacuum contactor designed for higher current range devices such as 200-600 amperes; and
FIG. 3 is an enlarged fragmentary sectional view through one side of the welded diaphragm bellows of the vacuum contactors of FIGS. 1 and 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, there is shown a first configuration of vacuum contactor particularly adapted for the lower current applications such as 100-200 amperes for reasons hereinafter appearing.
This vacuum contactor is generally cylindrical in form and is provided with a hermetically sealed, vacuum enclosure called a vacuum "bottle" that includes a ceramic insulator section, a stationary contact, a movable contact sealed by a bellows, and shields within the enclosure.
This enclosure 2 comprises an upper plate 4 and a lower plate 6 both being circular "disc" shaped with a center hole and preferably composed of stainless steel, and being connected at their peripheral portions by an electrically insulating tube or cylinder. This insulating tube has an insulating center section 8 connected by an upper metal section or ring 10 to upper plate 2 and connected by a lower metal section or ring 12 to lower plate 6.
As will be apparent, center section 8 is required to insulate the two contacts from one another. For this purpose, this center section is made of electrically insulating material such as glass, alumina ceramic, or the like and hermetically sealed and secured to upper ring 10 and lower ring 12.
Rings 10 and 12 are preferably copper tubing that is nickel plated prior to brazing to the upper and lower plates to form a hermetic seal therebetween.
Stationary contact 14 is assembled from a number of parts. A stationary stem 16 is the main supporting member for the stationary contact. It is composed of copper and has a reduced diameter upper end portion extending up through the round center hole in upper plate 4 so that the plate fits closely around the stem and against the shoulder of the latter, and the two parts are brazed together to form a hermetic seal therebetween.
This stem 16 is provided with a bore 16a therethrough having an enlarged diameter at its upper end into which an air evacuation tube 18 is inserted and brazed to form a hermetic seal. A hole 16b extends from this bore radially through the wall thereof to provide a passage for evacuating air from the enclosure when a pump is connected to tube 18. Tube 18 may be copper and is pinched to close it after the required amount of air has been pumped out.
To complete the stationary contact, a coined contact holder 20 is provided for securing a contact 22 to the lower end of the stem. This coined contact holder is provided with a short stub extending up from its center into the bore in stem 16 and is brazed to the stem to form a hermetic seal therebetween. Coined contact 22 is brazed to the lower surface of the contact holder.
Movable contact assembly 24 is assembled from a number of parts. A movable stem 26 is the main supporting member for the movable contact. It is composed of copper and has a bore therethrough with the lower end of this bore being tapped to provide a thread 26a to afford securing of a contact operating member thereto. A stainless steel bellows plate 28 is brazed to the upper end of movable stem 26 to close the bore therein with a hermetic seal. A cup-shaped bellows shield 30 rests on top of bellows plate 28 and is brazed thereto. A butt type movable contact 32 is brazed to the bottom within this cup-shaped bellows shield. The cylindrical sides of this bellows shield extend up around the stationary contact, contact holder and the lower end portion of the stationary stem. The distance between the cylindrical inner wall and the contact holder surface parallel to it is optimized to achieve minimum current chopping and maximum current interruption. The height of the cylindrical wall depends on the maximum opening gap between the contacts. It varies between one-half the gap length to six times gap length.
A welded diaphragm bellows 34 hermetically seals the movable contact to the enclosure while allowing the movable contact to be actuated to open and close the contacts. For this purpose, the upper end of the bellows is welded to the lower surface periphery of bellows plate 28. As shown in FIG. 1, the periphery of the lower surface of this bellows plate is provided with a reduced thickness flange 28a to facilitate welding the upper end of the welded bellows thereto in a hermetic sealing manner. Also, the lower end of the welded bellows is welded to the rim of the central hole in lower plate 6. The upper surface around this hole is provided with a reduced thickness rim 6a to facilitate welding the lower end of the bellows thereto in a hermetic sealing manner.
To provide a guide for axial movement of movable contact stem 26, a bushing 36 comprised of white molding material or the like is secured to lower plate 6 with epoxy or the like. This bushing has a short projection extending up into the hole in lower plate 6 against the reduced thickness rim around movable stem 26 to fill the space therebetween while guiding the movable stem and allowing it to be moved up and down therein.
A stainless steel shield 38 of cylindrical form is secured at its upper end into a round groove in the lower surface of upper plate 4. This shield is suspended between cup-shaped bellows shield 30 and insulating cylinder 8, about half-way therebetween, and extends down to about the bottom of bellows shield 30. This shield 38 shields the arcing products from ceramic cylinder 8 and provides a metal surface for the gases to condense on.
Bellows shield 30 shields the arcing products from the bellows and the overlap of the two shields increases the distance so as to keep the hot metallic vapor and particles away from the bellows. Another function of this shield is to maintain higher pressure close to the contacts. This will lower the current chopping level. Another function of this shield is to provide surface area for the purpose of collecting ions and condensing gases in order to improve the interruption capabilities of the device.
FIG. 2 shows a second configuration of vacuum contactor particularly adapted for higher current motor control applications such as 200-600 amperes for reasons hereinafter appearing. As is readily apparent in FIG. 2, this configuration is arranged to reduce to a minimum the amount of electrically insulating ceramic material used which is costly while affording a sufficient volume within the enclosure for the voltage rating of the vacuum contactor.
Typical voltage ratings for these vacuum contactors are 2.3 kilovolts and 4.16 kilovolts R.M.S. The 2.3 kv contactor must have an insulating ceramic that will withstand at least 10 kv while the 4.16 kv contactor must have an insulating member that will withstand at least 20 kv. This invention involves making these costly insulating members as small diameter and as short as possible consistent with the voltage withstanding requirements. The FIG. 1 configuration appears to be practical and economical for the lower current devices such as 100-200 amperes because at this current rating the ceramic insulator size is not prohibitive and it has one less part than does the FIG. 2 configuration. The FIG. 2 configuration appears to be practical and economical for the higher current devices such as 200-600 amperes because it decreases the ceramic size to a minimum while affording sufficient volume although it has one more part than the FIG. 1 configuration as will hereinafter appear.
In FIG. 2, reference characters like those in FIG. 1 are used for like parts.
As shown in FIG. 2, the insulating ceramic cylinder is placed in the reduced diameter upper section of the enclosure to provide effective insulation while maintaining sufficient volume.
The hermetically sealed enclosure is provided with three plates including an upper plate 40, a middle plate 42 and a lower plate 44, these plates being composed of stainless steel and each being provided with a central hole. The insulating cylinder or tube connects the peripheral portion of upper plate 40 to the rim of the hole in middle plate 42 to provide the aforesaid reduced diameter upper section of the enclosure. A stainless steel cylinder or tube 46 connects the peripheral portions of middle plate 42 and lower plate 44 to provide the large diameter lower section of the enclosure.
This insulating tube has an insulating center section 48 and copper rings 50 and 52 secured to opposite ends thereof in a hermetically sealed manner. Upper ring 50 is connected with a hermetic seal to the periphery of upper plate 40 and lower ring 52 is connected with a hermetic seal to the rim of the hole in middle plate 42. This insulating tube is like that shown in FIG. 1 except shorter and of smaller diameter.
Stationary contact 54 is generally similar to that in FIG. 1 except that its stationary stem 56 is longer so as to extend through the reduced diameter upper section of the enclosure into the larger diameter lower section thereof. This stem has a similar bore 56a and side hole 56b and is similarly mounted and sealed into the central hole in upper plate 40. Tube 18 is secured in the enlarged bore in the upper end of stem 56 and contact holder 20 and contact 22 are secured to the lower end of this stem, all as in the FIG. 1 configuration.
The movable contact assembly in FIG. 2 is similar to that in FIG. 1 including stem 26 and threaded bore 26a therein, bellows plate 28, bellows shield 30, movable contact 32 and welded diaphragm bellows 34. The only difference is that lower plate 44 has a slightly different peripheral configuration to accommodate stainless steel cylinder 46. The lower end of the bellows is welded to the reduced thickness rim 44a around the hole in the lower plate. And bushing 36 is cemented with epoxy in place to guide stem 26 as described in connection with the first configuration shown in FIG. 1.
As will be apparent, this FIG. 2 configuration does not require a shield like shield 38 of FIG. 1 since ceramic tube 48 is located in the reduced diameter upper section of the enclosure and, thus, is not in direct line with the arcing products leaving the contacts.
Although the FIG. 2 configuration has one more part than the FIG. 1 configuration, differing in an additional plate 42 and metal cylinder 46 as against shield 38 of FIG. 1, nevertheless it is more efficiently and economically adapted to the higher current applications of 200-600 amperes because of the reduced diameter insulating ceramic 48 while providing sufficient volume of vacuum with the large diameter metal cylinder 46 for its voltage rating.
Characteristics that are desired in a vacuum contactor for motor control application are minimum size of insulator, long life bellows and capability of assembly under 500° C.
While 10,000 operations might be sufficient for vacuum breakers for transmission line interruption, motor control vacuum contactors require a longer life of the order of a million operations or more.
While a formed bellows provides a long life such as 50,000 operations or more despite the heating to high temperature such as 800° C required for proper evacuation of transmission line vacuum interrupters, to get sufficient contact movement the formed bellows becomes prohibitively large. For example, for a given deflection, a formed bellows must be about 6 times as high, for example 21/4 inches as compared to 3/8 inch for a welded diaphragm bellows. However, a welded diaphragm bellows loses its life when heated to 800° C so that formed bellows have generally been used in vacuum interrupters and vacuum contactors.
The ceramic insulator is the big cost item in a vacuum contactor. To minimize this cost, the invention provides two configurations of vacuum contactors that are optimum for low current and high current ranges of motor control applications, respectively. While the ceramic is larger in FIG. 1, nevertheless, it is not so large as to be extremely costly for the 100-200 ampere range device. While the FIG. 2 configuration has one more part, nevertheless it has a smaller ceramic to optimize it for the 200-600 ampere range devices.
The invention provides a method of making these vacuum contactors that avoids having to bake them above 450° C, thereby enabling use of an extremely long life welded diaphragm bellows of AM-350 stainless steel, or the like.
______________________________________FIG. 1 Configuration FIG. 2 Configuration______________________________________a. Braze the stationary stem, a. Same, except four evacuation tube, contact holder joints contact, upper plate and suspended shield together at five joints in vacuum or other inert gas environ- ment.b. Braze the movable stem, bellows b. Same plate, bellows shield and contact together at three joints in vacuum or other inert gas environmentc. Weld the bellows to the bellows c. Same plate and lower plate (TIG* weld or electron beam) *Tungsten inert gas. d. Weld (TIG weld or electron beam) the lower (insulator) ring to the middle plate and the middle plate to the stain- less steel cylindere. Weld (TIG weld or electron beam) e. Same, except the lower plate to the envelope envelope is stainless (lower insulator ring) steel cylinder.f. Weld (TIG weld or electron beam) f. Same, except middle upper plate to envelope (upper plate to envelope insulator ring) (stainless steel cylinder)g. Bake the device 2-12 hours having g. Same the inside in the pressure range of 10.sup.-.sup.2 to 10.sup.-.sup.8 torr* and the out- side in vacuum or other inert gas environment at temperatures up to 450 degrees C. *1 torr = 1 mm Hgh. Clinch the evacuation tube h. Samei. Put mechanical protection on i. Same the sealed area.______________________________________
The key to using welded diaphragm bellows is the above method and the fact that for motor control applications the residual gas level inside the bottle does not have to be as low as for circuit interrupter applications. This is because vacuum contactors for motor control are in the rating range of 1.1 to 7.5 kv and 100-900 amperes whereas circuit interrupters for transmission line use are capable of interrupting 15 kv and 31,000 amperes.
Assembling the parts in accordance with the above methods does not require heating the complete assembly or the bellows at any time to temperatures above 450° C.
While bonding of metal to ceramic or glass requires higher temperatures such as 780° C, the insulating tube that includes the ceramic cylinder and the metal rings at the opposite ends thereof is made beforehand and then used as one of the integral parts in the above assembly method.
Limiting the heating to the aforesaid low temperature allows use of welded diaphragm bellows made from stainless steel AM-350, 347 or the like.
This affords the advantage of very short bellows, about one-sixth of the length of equivalently deflecting formed bellows of a given diameter, resulting in a reduced size of vacuum contactor. Another advantage gained therefrom is increase in mechanical life up to millions of operations, this being attained with the use of conventional stroke lengths of 0.06 to 1.5 inches.
With respect to the configuration shown in FIG. 2, a certain volume is necessary to achieve power interruption. This volume depends upon many variables including pressure, contact material, rating of power interruption, geometry of contacts, etc. This configuration affords the required volume within the enclosure without overly increasing the amount of material going into the ceramic insulator. Thus, the volume needed to maintain the pressure low, below 10.sup. -4 torr, is provided by the large metallic portion of the enclosure while using the minimum diameter of ceramic.
The length of the insulator is determined by the voltage rating of the vacuum contactor. The two contacts are electrically separated by the alumina ceramic or glass insulator. Each inch length of the insulator surface can withstand about 10 kv in air. Thus, the insulator of a device that is rated 20 kv can be as short as two inches, etc. But within the vacuum, below 10.sup. -4 torr, the distance between two metallic parts of different potential can be made much shorter, such as 0.06 to 1 inch, without breakdown or electrical leakage. This configuration of FIG. 2 uses these properties to attain the smallest insulator and smallest vacuum contactor. This configuration also omits the suspended shield of FIG. 1 and provides a large metallic surface for the gases to condense on to improve the interruption capabilities of the device.
FIG. 3 shows a cross-section through one side of the welded diaphragm bellows. As is apparent therein, the bellows is made from a plurality of stacked flexible washer-shaped elements having like annular curvatures formed therein to enhance their flexure. Each such element is welded around its inner edge to the element directly above it and is welded around its outer edge to the element directly below it so as to close the inner space from the outside with a hermetic seal.
While the apparatus and method hereinbefore described is effectively adapted to fulfill the objects stated, it is to be understood that the invention is not intended to be confined to the particular preferred embodiments of vacuum contactors for motor control and methods of making disclosed, inasmuch as they are susceptible of various modifications without departing from the scope of the appended claims.
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A vacuum contactor for motor control applications and method of making the same that produces a switch of minimum size and extremely long mechanical life. This method comprises the step of heating the vacuum assembly to not over 450° C during the evacuation process thereby allowing use of welded diaphragm bellows having the attendant advantages of much smaller size and longer life for a given length of stroke as compared to formed bellows. Because the operating conditions for motor control applications do not require as high voltage and current breakdown levels and thus the residual gas level inside the vacuum contactor enclosure need not be as low as in the case of circuit breaker (interrupter) applications, limiting the heating to not over 450° C allows use of AM-350 stainless steel welded diaphragm bellows without sacrificing its required mechanical life. Furthermore, the bellows shield is designed to achieve minimum current chopping and at the same time maintain high current interruption capabilities. Two types of vacuum switch configurations made according to this method are disclosed.
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PRIORITY CLAIM
[0001] The present application claims priority to U.S. Provisional Application No. 60/552,653 filed Mar. 13, 2004, the contents of which are incorporated herein by reference.
RELATED APPLICATIONS
[0002] The present application is related to Attorney Docket Numbers 010-0011, 010-0011A, 010-0011B, 010-0011C, 010-0013, 010-0019, 010-0028 and 010-0030 filed on the same day as the present application. The content of each of these cases is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates to triggers in the context of compute resource management and more specifically to a system and method of generating triggers which could be attached to any other scheduling object.
[0005] 2. Introduction
[0006] The present invention applies to computer clusters and computer grids. A computer cluster may be defined as a parallel computer that is constructed of commodity components and runs commodity software. FIG. 1 illustrates in a general way an example relationship between clusters and grids. A cluster 110 is made up of a plurality of nodes 108 A, 108 B, 108 C, each containing computer processors, memory that is shared by processors in the node and other peripheral devices such as storage discs connected by a network. A resource manager 106 A for the node 110 manages jobs submitted by users to be processed by the cluster. Other resource managers 106 B, 106 C are also illustrated that may manage other clusters (not shown). An example job would be a weather forecast analysis that is compute intensive that needs to have scheduled a cluster of computers to process the job in time for the evening news report.
[0007] A cluster scheduler 104 A may receive job submissions and identify using information from the resource managers 106 A, 106 B, 106 C which cluster has available resources. The job would then be submitted to that resource manager for processing. Other cluster schedulers 104 B and 104 C are shown by way of illustration. A grid scheduler 102 may also receive job submissions and identify based on information from a plurality of cluster schedulers 104 A, 104 B, 104 C which clusters may have available resources and then submit the job accordingly.
[0008] Grid/cluster resource management generally describes the process of identifying requirements, matching resources to applications, allocating those resources, and scheduling and monitoring grid resources over time in order to run grid applications as efficiently as possible. Each project will utilize a different set of resources and thus is typically unique. In addition to the challenge of allocating resources for a particular job, grid administrators also have difficulty obtaining a clear understanding of the resources available, the current status of the grid and available resources, and real-time competing needs of various users.
[0009] Several books provide background information on how to organize and create a cluster or a grid and related technologies. See, e.g., Grid Resource Management, State of the Art and Future Trends , Jarek Nabrzyski, Jennifer M. Schopf, and Jan Weglarz, Kluwer Academic Publishers, 2004; and Beowulf Cluster Computing with Linux , edited by William Gropp, Ewing Lusk, and Thomas Sterling, Mass. Institute of Technology, 2003.
[0010] Virtually all clusters have been static which means that an administrator establishes the policies for the cluster, sets up the configuration, determines which nodes have which applications, how much memory should be associated with each node, which operating system will run on a node, etc. The cluster will stay in the state determined by the administrator for a period of months until the administrator takes the entire machine off-line to make changes or modifications. Then the machine is brought back on-line where another 10,000-100,000 jobs may be run on it.
[0011] Within this static cluster environment, there is the ability to have something called a job step, a job step allows an application to prepare or modify its environment within the constraints of the compute resources provided by the cluster. For example a job may consist of three steps, the first step is puffing data off of a storage system and transferring the data onto a local file system. The second step may actually process the data and a third step may take the data and go through a second processing step and push it back out to a storage system. These job steps enable some additional functionality for the job in that it allows a job to work within the environment they have.
[0012] However, there are some deficiencies in this process. Using job steps does nothing for allowing the jobs to actually change the compute environment provided by the cluster in any way. Job steps operate within the cluster environment but have no control or ability to maximize efficiencies within the environment or adjust the environment. They are static in the sense that they are limited to manipulation of tasks within the given cluster environment. What is needed in the art is a method of improving the efficiency of the compute environment via a device associated with a job or other object.
SUMMARY OF THE INVENTION
[0013] Additional features 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 features and advantages of the invention may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth herein.
[0014] The present invention addresses the deficiencies in the art discussed above. The cluster that receives a job submission according to the present invention is dynamic in that the cluster and the resources associated with the cluster may dynamically modify themselves to meet the needs of the current workload. To accomplish this dynamic component of the cluster, the present invention further involves introducing triggers.
[0015] A trigger is an object which can be attached or associated with any other scheduling object. A scheduling object can be, for example, one of: a compute node, compute resources, a reservation, a cluster, user credentials, groups or accounts, a job, a resource manager, other peer services and the like. Any scheduling object can have any number of triggers associated with it.
[0016] The invention comprises various embodiments associated with dynamic clusters and triggers. These embodiments include systems, methods and computer-readable media that provide the features of the invention. The method embodiment of the invention comprises a method for dynamically modifying a cluster, the method comprising attaching a trigger to a scheduling object and firing the trigger based on a trigger attribute, wherein the cluster environment is modified by an action take by the trigger.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to describe the manner in which the above-recited and other advantages and features of the invention can be obtained, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
[0018] FIG. 1 illustrates generally a prior art arrangement of clusters in a grid;
[0019] FIG. 2 illustrates a trigger attached to an object;
[0020] FIG. 3 illustrates an example of the user of triggers according to an aspect of the invention;
[0021] FIG. 4 illustrates a method according to an embodiment of the invention; and
[0022] FIG. 5 illustrates a graphical user interface used to create triggers.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Various embodiments of the invention are discussed in detail below. While specific implementations are discussed, it should be understood that this is done for illustration purposes only. A person skilled in the relevant art will recognize that other components and configurations may be used without parting from the spirit and scope of the invention.
[0024] The “system” embodiment of the invention may comprise a computing device that includes the necessary hardware and software components to enable a workload manager or a software module performing the steps of the invention. Such a computing device may include such known hardware elements as one or more central processors, random access memory (RAM), read-only memory (ROM), storage devices such as hard disks, communication means such as a modem or a card to enable networking with other computing devices, a bus that provides data transmission between various hardware components, a keyboard, a display, an operating system and so forth. There is no restriction that the particular system embodiment of the invention has any specific hardware components and any known or future developed hardware configurations are contemplated as within the scope of the invention when the computing device operates as is claimed.
[0025] The present invention enables the dynamic modification of compute resources within a compute environment such as a cluster or a grid by the use of triggers. FIG. 2 illustrates a trigger 204 being attached to an object 202 . The object 202 is preferable a scheduling object and each trigger 204 is configured with a plurality of attributes. Example objects include a compute node, a reservation within a cluster, a cluster itself, a user, a job submitted by a user to a cluster manager, a resource manager, etc. As can be appreciated, an “object” in the context of cluster management may be any number of concepts to which a trigger may be attached.
[0026] An example attribute associated with a trigger includes an event type, which means that one would like this trigger to fire or execute based on a particular event occurring such as the creation of the object, the starting, execution, cancellation or termination of an object, or an object state.
[0027] Other attributes associated with a trigger include a time-out, an offset feature, a particular action (such as send an e-mail to the administrator), dependencies, an argument list, a state and a threshold value. This is not meant to be an exhaustive complete list. Other attributes may also be attached to the trigger. For example, meaning dependencies can be based on attributes within the object, wherein if a job is now running, a dependency may be that it fires if a parameter is set to “true”. In that case, the trigger also has a variable it sets to cascade other triggers by setting variables that cause other triggers to fire. Such parameters may relate to things like a threshold, a re-arm time, time-out values and durations. In this manner, a cascade of triggers may fire based on various modified and set parameter from one trigger to the next. Other values that may be used to fire triggers include such parameters as: user credentials, jobs, groups, jobs per user and other types of thresholds. For example, whenever a user exceeds X number of jobs, launch a trigger to take an action. A group-based parameter example is: (1) if user John has more than 18 idle jobs, then send a note to an administrator; and (2) if a group “staff” resource availability query receives a reply with resources more than two hours out, then launch a trigger to modify reservation Y to provide more resources.
[0028] The offset feature involves establishing that the trigger will fire either before or after an event has occurred. The example trigger in FIG. 3 illustrates their use in a hosting environment in which a customer wants to reserve a block of resources for a particular time frame and the administrator wants to dynamically provision those resources. FIG. 3 illustrates a reservation 302 that is processing in time. A trigger 304 is attached to the object with attributes including an offset to begin a certain period of time (say two minutes) 312 after the reservation 302 begins its process. The trigger 304 has as an attribute an action to take which is to set up a network and generate an ARGLIST variable called $IPlist and return that value to the reservation environment. The trigger 304 also transmits the $IPList to another trigger 306 . The trigger 306 has a start time offset but also a dependency that it does not fire until the $IPList variable is set. Once the variable is set, the trigger 306 sets up a storage area network, brings in the resources and makes the resources available to the reservation. When trigger 306 completes, a third trigger 308 performs an operating system setup, which also has a dependency on the $IPList variable being set to a value as well as a variable being set to “true”. When both of those parameters are satisfied, trigger 308 fires and sets up the operating system and application environment and completes. The output of trigger 308 is a parameter stating whether the operating system setup was successful (“true”) or not.
[0029] Independent of these triggers is an additional trigger 310 that is set to fire at a fixed offset from the start of the reservation, and it performs a health check to verify that the OS setup variable which is setup by the trigger 308 is true. If it is not set to true, then trigger 310 is designed to do two things: (1) cancel the reservation itself and send an e-mail to the administrator and end user notifying them that there has been a failure and the reservation will not be available; and (2) retry the initial setup triggers or look for additional local in time at which these blocked resources could be made available and send an e-mail to the user saying we'll retry at this particular time. All of this is performed automatically through the use of triggers.
[0030] The above example provides an illustration of the various features of triggers, including the ability to start at an offset value, perform certain actions, having certain dependencies based on data being processed and received or other kinds of dependencies and produce and receive argument lists.
[0031] In addition, triggers can specify arbitrary actions allowing it to modify the scheduling state, to execute some process, to pull something in from off the Internet or to update a database. Any arbitrary action that can modify the environment, including destroying the object or reconfiguring the object. Furthermore, triggers have the ability to specify dependencies, saying the trigger can only fire when an event has occurred, the offset has been satisfied and certain other conditions such as variables have been set or other triggers completed with certain states. Each trigger can begin with a variable called in from an ARGLIST which allows you to pass in either static or dynamic variables to modify its behavior.
[0032] Also associated with triggers is the concept of a trigger timeout. This feature allows one to determine if a trigger has not fired yet or if it has completed successfully, unsuccessfully or if it's still in process of completing. With all these capabilities, an administrator can have essentially arbitrary control over decision making and process flow to modify the dynamic cluster environment in any way desired.
[0033] There are a number of ways to create a trigger. FIG. 5 illustrates a graphical tool 500 to simply point and click to associate the trigger and attach it to an object. The tool allows the user to select: the creation of a trigger when a reservation starts (or other selectable time via a drop down menu) 502 , the trigger start time for a certain number of minutes before or after a reservation starts 504 , an action launched by a trigger such as to cancel the reservation 506 , an executable file to execute 508 or to receive an argument list 510 and a reservation utilization threshold 512 .
[0034] Any action may launch a trigger. For example, if a resource manager goes down, or is a software license is about to expire, or a software application that is going to have a job executed with use of the software and it is out-of-date. Any event may launch a trigger.
[0035] The second method is to set it up in a configuration file a Moab™ configuration file is simply a flat text file which specifies associations and definitions of triggers. A third way is to simply use command line arguments to generate a trigger. These triggers can be created remotely over the network interface or locally. The following is an example of a command line method of creating triggers by user “Smith”:
[0000]
mrsvctl -c -h smith -T \
‘Sets=$Var1.$Var2.$Var3.!Net,EType=start,AType=exec,Action=/tmp/Net.sh,Timeout=1
0’\
-T \
Requires=$Var1.$Var2.$Var3,Sets=$Var4.$Var5,EType=start,AType=exec,Action=/tmp/
FS.sh′\
-T \
Requires=$Var1.$Var2.$Var3.$Var4.$Var5,Sets=!NOOSinit.OSinit,Etype=start,AType=exe
c,Action=
/tmp/OS.sh+$Var1:$Var2:$Var3:$Var4:$Var5′ \
-T \
Requires=failed,AType=cancel,EType=start \
-T \
Eype=start,Requires=OSinit,AType=exec,Action=/tmp/success.sh \
-T \
Requires=Net,EType=start,Sets=failed,AType=exec,Action=/tmp/fail.sh
[0036] This demonstrates a string of triggers, the first two set variables, the third one requires each of those variables to be set and there are also triggers that activate in case of failure.
[0037] An important feature that differentiates triggers from the job step is that there are other systems that allows one to have some sense of dependencies and modification but that is only within a single, given application or job. Job steps can modify their own data and the like but there's nothing that can modify either scheduling policy or scheduling objects, or scheduling environment, like triggers can. Triggers allow one to take any arbitrary action based on any arbitrary set of sensors. Triggers enable puffing in a wide ranging scope of information and having a wide scope of control. They are preferable written in the “c” programming language but there are no constraints on the type of programming language.
[0038] One of the attributes introduced above that is associated with a trigger is the threshold attribute. In addition to being able to say that a trigger will fire, when its dependencies are satisfied and its event has occurred and its offset has been satisfied, one may also specify whether a particular threshold and its threshold criteria has been satisfied. This feature allows one to have triggers that fire when particular qualities of service are not satisfied, when queue times have been exceeded, when anything that correlates to basically system performance has or has not been satisfied. When these metrics have not been satisfied or have been satisfied this provides some way one can have arbitrary actions occur.
[0039] Other examples of trigger usage are that an administrator can attach a trigger to a node and allow a node monitor such as Ganglia to perform monitoring activities such as detecting keyboard touches. So if a local user has begun to type or if the system detects a high level of data transmission or swapping, a trigger action may adjust the priority of that node so that it is no longer as likely to be selected for batch work load. The priority adjustment may reduce the probability that the node would be selected for a large job like a batch work load.
[0040] Performance triggers illustrate another type of trigger that is associated with a particular group or a particular user and a threshold parameter. The parameter may be a performance threshold parameter that is related to, for example, an average response time that is below a particular threshold. If that particular threshold is not satisfied, then the trigger fires and sends an e-mail off to an administrator and adjusts the priority of that user's jobs. The trigger may also dynamically modify the cluster resources to accommodate the at least one user's activities so that the user experiences a performance level at least at the threshold parameter.
[0041] Embodiments within the scope of the present invention may also include computer-readable media for carrying or having computer-executable instructions or data structures stored thereon. Such computer-readable media can be any available media that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store desired program code means in the form of computer-executable instructions or data structures. When information is transferred or provided over a network or another communications connection (either hardwired, wireless, or combination thereof) to a computer, the computer properly views the connection as a computer-readable medium. Thus, any such connection is properly termed a computer-readable medium. Combinations of the above should also be included within the scope of the computer-readable media.
[0042] Computer-executable instructions include, for example, instructions and data which cause a general purpose computer, special purpose computer, or special purpose processing device to perform a certain function or group of functions. Computer-executable instructions also include program modules that are executed by computers in stand-alone or network environments. Generally, program modules include routines, programs, objects, components, and data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-executable instructions, associated data structures, and program modules represent examples of the program code means for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps.
[0043] Those of skill in the art will appreciate that other embodiments of the invention may be practiced in network computing environments with many types of computer system configurations, including personal computers, hand-held devices, multi-processor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, and the like. Embodiments may also be practiced in distributed computing environments where tasks are performed by local and remote processing devices that are linked (either by hardwired links, wireless links, or by a combination thereof) through a communications network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices.
[0044] Although the above description may contain specific details, they should not be construed as limiting the claims in any way. Other configurations of the described embodiments of the invention are part of the scope of this invention. Accordingly, the appended claims and their legal equivalents should only define the invention, rather than any specific examples given.
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The present invention provides for systems and methods of dynamically controlling a cluster or grid environment. The method comprises attaching a trigger to an object and firing the trigger based on a trigger attribute. The cluster environment is modified by actions initiated when the trigger is fired. Each trigger has trigger attributes that govern when it is fired and actions it will take. The use of triggers enables a cluster environment to dynamically be modified with arbitrary actions to accommodate needs of arbitrary objects. Example objects include a compute node, compute resources, a cluster, groups of users, user credentials, jobs, resources managers, peer services and the like.
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This invention relates to a process to make high active detergent particles from surfactant blends comprising a major amount of linear alkylbenzene sulphonate surfactant.
BACKGROUND AND PRIOR ART
To reduce the chemicals used in the laundry washing process it has been proposed to decrease the builder salts in laundry detergent formulations. Without other formulation changes, this reduction could adversely affect the performance of the composition in hard water. It has been proposed to ameliorate this problem by using surfactant blends that are tolerant of the presence of hardness ions in the wash water, in particular blends tolerant to calcium ions. These surfactant blends have been termed “calcium tolerant surfactant blends”.
For the detergent formulator use of such calcium tolerant surfactant blends poses a new problem. Builder materials have often been included in the formulation not only to provide hard water detergency performance, but also to enable efficient manufacture of free flowing granular detergent formulations. Thus, reduction of builders in a formulation, whilst leaving it in the form of free flowing particles, is not straightforward.
Extrusion of detergent compositions is known.
WO 9932599A1 describes a method of manufacturing surfactant particles comprising an anionic surfactant, wherein the method may comprise drying an anionic surfactant and subsequently extruding through apertures, at an elevated temperature, the dried anionic surfactant, optionally blended with, builder, water, polymer and/or nonionic surfactant, and forming the extruded strands into particles, e.g. by cutting and spheronising. The apertures may comprise plain cylindrical apertures of diameter not exceeding 2 mm.
In WO 9932599A1 the material fed to the extruder is preferably an anionic surfactant paste, whose activity (i.e. anionic surfactant content) is most preferably at least 90% wt. The preferred materials of high activity may be prepared by subjecting the as-prepared surfactants to a drying step prior to the extrusion step. Examples of equipment which can achieve this include a rotary drum dryer, or a Chemithon Turbo Tube® drier, or, most preferably, a wiped film evaporator. Preferably, the dried product is a waxy or pasty solid at ambient temperature.
In one preferred method, a feed material comprises an anionic surfactant which contains 2-10% wt of water, and whose activity is 90-98% wt. It is found that the presence of this water aids the processing of the surfactant, within the extruder and/or during a downstream spheronisation step, if carried out. Alternatively, a dried surfactant may be employed in the feed material, and there may be a separate addition of water to aid processing.
WO 9932599A1 states that in some detergent formulations it is desired to have extremely low quantities of water present, or none at all. In such formulations, a non-ionic surfactant may aid the processing of the anionic surfactant within the extruder, and/or their downstream handling. Thus, in one preferred method an anionic surfactant and a non-ionic surfactant are present. The weight ratio of non-ionic surfactant to the anionic surfactant is suitably up to 1 part, preferably up to 0.5 parts, of non-ionic surfactant per part of anionic surfactant (with reference to their active contents). A non-ionic surfactant, when present, may suitably be added at any stage prior to the stage of mechanical working in the extruder; thus it may be added to the material comprising the anionic surfactant prior to the prior drying step (if carried out); prior to the feeding of the material comprising the anionic surfactant into the extruder; at the same time as the feeding of the material comprising the anionic surfactant into the extruder; or subsequent to the feeding of the material comprising the anionic surfactant into the extruder, through a separate feed point, during or, more preferably, prior to the mechanical working thereof.
One preferred class of anionic surfactants disclosed in WO 9932599A1 comprise the alkali metal (preferably sodium) alkyl sulphates (PAS). Another comprises alkali metal (preferably sodium) alkylaryl sulphonates (especially alkylbenzene sulphonates (LAS)).
It is preferred that the particles contain a builder. A builder in particulate form is suitably added to the material comprising the anionic surfactant during or, preferably, prior to the mechanical working thereof. Preferably, the builder, when present, is added to the material comprising the anionic surfactant within the extruder. A builder, when present, may suitably be present in an amount of from 0.1-10 parts per part of the anionic surfactant (active content), by weight. When the anionic surfactant is, or is predominantly, an alkali metal alkylaryl sulphonate, the builder may suitably be present in an amount of from 0.1-5 parts per part of the anionic surfactant (active content), by weight, preferably 0.1-1, most preferably 0.15-0.5 parts, by weight. The main ingredients of the extruded particles are preferably anionic surfactant and builder.
According to WO 9932599A1 following the extrusion process, it may be necessary to change the appearance and handling characteristics of the extrudate strands. This may be conveniently achieved by means of “chopping” the extrudate to the required length. A spheronising procedure may be carried out, if wished, on the chopped extrudate.
In all examples of WO 9932599A1 the particles were chopped into pieces in standard manner and then spheronised to give roughly spherical particles of approximately 1 mm diameter. Examples 1, 3, 4, 5 and 6 used alkyl sulphate anionic surfactant paste (PAS). As will be clear from examples 1 and 6, PAS is an unusual surfactant. It can be extruded without much drying or without any inorganic builder structurant present. This is due to the known fact that it has a hardness of about 2 MPa, which is relatively independent of the amount of water in the paste at below 10% moisture. Thus, it could be broken up in example 1 and it could be extruded satisfactorily, without need for any inorganic structuring in example 6. This contrasts markedly with the LAS surfactant used in example 2 of WO 9932599A1. The skilled person is well aware that LAS-rich pastes are sticky. Thus, it is conventional to add large amounts of solid structuring and liquid carrying materials, especially if further liquid-like material such as non ionic surfactant is also being added. Note that example 2 does not use any nonionic surfactant.
Example 2 declares a water content of 2-4% (based on “100-active” as on page 5 lines 25-27 of the application). At such high water levels LAS is too soft and sticky to extrude and cut. Thus, high levels of solid matter are normally added, like the 42% builder solids added to the extruder in Example 2. If nonionic had also been added, as in other examples of WO 9932599A1, using PAS, even higher levels of the solid builder addition would have been needed. The nonionic surfactant added to the extruder would not be molecularly blended with the LAS and would tend to be squeezed to the outside of the extruded strands, making them even stickier in the absence of solid builder carrier material to “soak them up”.
WO 9932599A1 envisages that nonionic surfactant could be added into the anionic surfactant before it enters the extruder, rather than in the extruder. But it does not perform this variant and the additional benefits of doing it for LAS rich, rather than PAS rich, compositions are not disclosed. The surfactants are not disclosed to be dried to a moisture content of less than 2%.
GB1303479 describes the formation of a water-soluble cleaning composition by extrusion of particles of length 0.5-10 mm. and cross-sectional area 0.04-0.8 mm 2 each comprising (a) a higher (C 9-18 ) alkyl aryl sulphonate, (b) a lower (C 1-3 ) alkyl benzene sulphonate, (c) an inorganic salt and (d) water. In one embodiment (Example 1), the dry ingredients are ground together in a mill, mixed with wet ingredients in a ribbon amalgamator and milled into ribbons, which are carried by conveyer belt to a plodder. The plodder is equipped with a wire mesh of 0.5 mm. openings and a perforated plate having holes, which taper from 12 to 16 mm, with the larger diameter at the exit. The material is extruded through the plate, cooled by an air jet and then carried on a conveyer belt through a further air flow to a granulator fitted with an 8-mesh screen, which breaks the extruded strands into the required lengths. This document proposes the addition of sodium aryl sulphonate as a hydrotrope, to get fast dissolution. Thus, in the examples, there are comparatively low levels of surfactants in order to make space for the high levels of hydrotrope and builders. The drying process appears to happen post-extrusion. The particles have small cross-sectional area and are relatively long at 3 to 4 mm.
Surfactant blends comprising linear alkylbenzene sulphonate (LAS) and at least one co-surfactant have been shown to provide excellent detergency, even in the presence of hardness ions. However, these blends tend to be soft and lead to sticky compositions that cake upon storage.
This is recognised in U.S. Pat. No. 5,152,932(A), which discloses neutralisation of PAS/LAS blends using concentrated caustic in a loop reactor. The neutralized product preferably has less than or equal to about 12% by weight of water.
It is most preferred that essentially no detergency builders or additional organic materials are fed into the continuous neutralization system. Mixtures of PAS and LAS are preferred because of improved dispersibility of detergent particles formed from a paste made with the mixture. The final ratio of PAS to LAS should be between 75:25 and 96:4, preferably between 80:20 and 95:5. Thus the compositions disclosed should have less than 51% LAS. The keeping of LAS to a lesser amount is preferred because the neutralized material is then not unacceptably sticky, yet the particles formed from the cooled paste are dispersible in 15.5° C. water. Paste made from alkyl benzene sulfonic acid alone is said to be soft, sticky, and therefore difficult to form into non-sticky, discrete surfactant particles.
When 73% active caustic is used, the molten paste ordinarily has between about 9 and 11% by weight of water. This water level is too high to render LAS rich compositions non sticky.
The process further contemplates the blending of PEG or nonionic with the anionic pastes. There are no examples using nonionic.
This document says that detergent particles can be formed in various ways from the neutralized product exiting the continuous neutralization system. The molten paste can be atomized into droplets in a prilling (cooling) tower. To avoid prilling at all, the molten paste can be simultaneously cooled and extruded, and cut or ground into desirable particle sizes. A third choice is to allow the molten paste to cool on a chill roll, or any heat exchange unit until it reaches a doughy consistency, at which point other detergent ingredients can be kneaded in. The resulting dough can then be granulated by mechanical means.
A fourth and preferred choice is to cool the molten paste into flakes on a chill roll, then grind the flakes to the desired particle size. If additional drying is required, the cooled flakes can be dried in a rotary drum with hot air or in a fluid bed prior to grinding.
There are no examples using extrusion. This disclosure teaches against the use of LAS rich systems. Example IV used LAS. Even with addition of PEG, the 9 wt % water cooled product is said to be solid in nature but much stickier than the PAS examples. Similarly the PAS rich example V (with some LAS) is said to have improved dispersibility compared to PAS alone as active, but that as the level of LAS is increased, the softness and stickiness of the particle increases. At high LAS levels, it is said that the particles are less suitable for use as detergent particles because of their stickiness. According to the data in this application, the best compromise between low stickiness and good dispersibility is an alkyl sulfate/alkyl benzene sulfonate ratio of about 88/12 i.e. a significant excess of PAS over LAS and a LAS content of well below 51%.
One solution to this stickiness/caking problem for high LAS blends that does not involve using builder in the mix is to enclose the detergent in a rigid capsule as proposed in WO2006/002755. This solution is excellent for use in washing machines but it has drawbacks when the dose needs to be fine tuned for the amount of laundry or water used, as is often the case for hand washing of laundry.
Yet a further solution is to coat the sticky granules. Such a stickiness reducing coating is described in U.S. Pat. No. 7,022,660(B1), which relates to detergent particles having a coating or partial coating layer of a water-soluble material.
The particle core may comprise a detergent particle, agglomerate, flake etc. The coated particles have a number of improved properties among which is that the coated particles provide improved clumping and flowability profiles to detergent products containing the particles. The particle coating layer provides a coating, which is crisper and non-tacky. While effective at improving flowability in all detergent products, it is particularly effective at preventing clumping in products containing surfactants which are more difficult to dry to a non-tacky state including nonionic surfactants, linear alkyl benzene sulfonates (“LAS”), and ethoxylated alkyl sulfates or in detergent products containing high amounts of surfactant actives (i.e. greater than about 25 wt % surfactant active).
While such a coating modifies the properties of the finished detergent particle, it does not solve the problem of providing a non-sticky and easily cuttable output from the extruder. In a production plant, the material exiting the extruder must be hard enough to cut into repeatable sized particles that does not deform as the cutter passes through it, stick neither to the cutter nor to each other. They must also be hard and non-sticky enough to be used, or to be stored and handled in bulk until they are coated if a coating is to be applied. This might entail them being put into a big bag and even transported to another plant. Thus the solution of applying a coating is not sufficient to solve the problem of stickiness of LAS that is not structured with large, typically 30% or more, amounts of inorganic particles
Thus, the present inventors sought a solution to the problem of caking of particulate detergent compositions comprising high active surfactant blends with a major part of LAS, which did not need a special unit dose storage container for the detergent particles of the composition, or use structuring of the particles with a high (>10%) incorporation high inorganic solids loading in the particles.
SUMMARY OF THE INVENTION
According to the present invention there is provided a process for manufacturing detergent particles comprising the steps of:
a) forming a liquid surfactant blend comprising a major amount of surfactant and a minor amount of water, the surfactant part consisting of at least 51 wt % linear alkylbenzene sulfonate and at least one co-surfactant, the surfactant blend consisting of at most 20 wt % nonionic surfactant; b) drying the liquid surfactant blend of step (a) in an evaporator or drier to a moisture content of less than 1.5 wt % and cooling the output from the evaporator or dryer; c) feeding the cooled material, which output comprises at least 93 wt % surfactant blend with a major part of LAS, to an extruder, optionally along with less than 10 wt % of other materials such as perfume, fluorescer, and extruding the surfactant blend to form an extrudate while periodically cutting the extrudate to form hard detergent particles with a diameter across the extruder of greater than 2 mm and a thickness along the axis of the extruder of greater than 0.2 mm, provided that the diameter is greater than the thickness; d) optionally, coating the extruded hard detergent particles with up to 30 wt % coating material, preferably selected from inorganic material and mixtures of such material and nonionic material with a melting point in the range 40 to 90° C.
To facilitate extrusion it may be advantageous for the cooled dried output from the evaporator or drier stage (b) comprising at least 95 wt % preferably 96 wt %, more preferably 97 wt %, most preferably 98 wt % surfactant to be transferred to a mill and milled to particles of less than 1.5 mm, preferably less than 1 mm average diameter before it is fed to the extrusion step (c).
To modify the properties of the milled material a powdered flow aid, such as Aerosil®, Alusil®, or Microsil®, with a particle diameter of from 0.1 to 10 μm may be added to the mill in an amount of 0.5 to 5 wt %, preferably 0.5 to 3 wt % (based on output from the mill) and blended into the particles during milling.
The output from step b, or the intermediate milling step, if used, is fed to the extruder, optionally along with minor amounts (less than 10 wt % total) of other materials such as perfume and/or fluorescer, and the mixture of materials fed to the extruder is extruded to form an extrudate with a diameter of greater than 2 mm, preferably greater than 3 mm, most preferably greater than 4 mm and preferably with a diameter of less than 7 mm, most preferably less than 5 mm, while periodically cutting the extrudate to form hard detergent particles with a maximum thickness of greater than 0.2 mm and less than 3 mm, preferably less than 2 mm, most preferably less than about 1.5 mm and more than about 0.5 mm, even 0.7 mm. Whilst the preferred extrudate is of circular cross section, the invention also encompasses other cross sections such as triangular, rectangular and even complex cross sections, such as one mimicking a flower with rotationally symmetrical “petals”. Indeed the invention can be operated on any extrudate that can be forced through a hole in the extruder or extruder plate; the key being that the average thickness of the extrudate should be kept below the level where dissolution will be slow. As discussed above this is a thickness of about 2 mm. Desirably multiple extrusions are made simultaneously and they may all have the same cross section or may have different cross sections. Normally they will all have the same length as they are cut off by the knife. The cutting knife should be as thin as possible to allow high speed extrusion and minimal distortion of the extrudate during cutting. The extrusion should preferably take place at a temperature of less than 45° C., more preferably less than 40° C. to avoid stickiness and facilitate cutting. The extrudates according to the present process are cut so that their major dimension is across the extruder and the minor dimension is along the axis of the extruder. This is the opposite to the normal extrusion of surfactants. Cutting in this way increases the surface area that is a “cut” surface. It also allows the extruded particle to expand considerably along its axis after cutting, whilst maintaining a relatively high surface to volume ratio, which is believed to increase its solubility and also results in an attractive biconvex, or lentil, appearance. Elsewhere we refer to this shape as an oblate spheroid. This is essentially a rotation of an ellipse about its minor axis.
It is surprising that at very low water contents the LAS containing surfactant blends can be extruded to make solid detergent particles that are hard enough to be used without any need to be structured by inorganic materials or other structurants as commonly found in prior art extruded detergent particles. Thus, the amount of surfactant in the detergent particle can be much higher and the amount of builder in the detergent particle can be much lower.
Preferably the blend in step (a) comprises at least about 60 wt %, most preferably at least about 70 wt % surfactant and preferably at most about 40 wt %, most preferably at most 30 wt % water, the surfactant part consisting of at least 51 wt % linear alkyl benzene sulphonate salt (LAS) and at least one co-surfactant;
Preferably, the co-surfactant is chosen from the group consisting of: SLES, and nonionic, together with optional soap and mixtures thereof. The only proviso is that when nonionic is used the upper limit for the amount of nonionic surfactant has been found to be 20 wt % of the total surfactant to avoid the dried material being too soft and cohesive to extrude because it has a hardness value less than 0.5 MPa.
Preferably, the surfactant blend is dried in step (b) to a moisture content of less than 1.2 wt %, more preferably less than 1.1 wt %, and most preferably less than 1 wt %.
Drying may suitably be carried out using a wiped film evaporator or a Chemithon Turbo Tube® drier.
Optionally, and preferably, the extruded hard detergent particles are coated by either:
(i) transferring them to a fluid bed and spraying onto them up to 30 wt % (based on coated detergent particle) of inorganic material in aqueous solution and drying off the water; or (ii) dry coating with up to 30 wt % of a water soluble or insoluble particulate of mean PSD<100 μm followed by spraying with either aqueous or non-aqueous liquid and optionally drying/cooling.
If the coating material is not contributing to the wash performance of the composition then it is desirable to keep the level of coating as low as possible, preferably less than 20 wt %, more preferably less than 15 wt % or even 10 wt % or as low as 5 wt %, especially for larger extruded particles with a surface area to volume ratio of greater than 4 mm −1 .
Surprisingly we have found that at low coating levels the appearance of the coating is very pleasing. Without wishing to be bound by theory, we believe that this high quality coating appearance is due to the smoothness of the underlying extruded and cut particle. By starting with a smooth surface, we unexpectedly found it easy to obtain a high quality coating finish (as measured by light reflectance and smoothness) using simple coating techniques.
The invention also provides a detergent composition comprising at least 70 wt %, preferably at least 85 wt % of coated particles made using the process according to the invention. However, compositions with up to 100 wt % of the particles are possible when basic additives are incorporated into the extruded particles, or into their coating. The composition may also comprise, for example, an antifoam granule.
When the particle is coated it is preferred if the coating is coloured. Particles of different colours may be used in admixture, or they can be blended with contrasting powder. Of course, particles of the same colour as one another may also be used to form a full composition. As described above the coating quality and appearance is very good due to the excellent surface of the cut extrudates onto which the coating is applied in association with the large particle size and S/V ratios of the preferred particles.
It is particularly preferred that the detergent particles comprise perfume. The perfume may be added into the extruder or premixed with the surfactant blend in the mill, or in a mixer placed after the mill, either as a liquid or as encapsulated perfume particles. In an alternative process, the perfume may be mixed with a nonionic material and blended. Such a blend may alternatively be applied by coating the extruded particles, for example by spraying it mixed with molten nonionic surfactant. Perfume may also be introduced into the composition by means of a separate perfume granule and then the detergent particle does not need to comprise any perfume.
DETAILED DESCRIPTION OF THE INVENTION
The Surfactant Blend
Surfactant blends that do not require builders to be present for effective detergency in hard water are preferred. Such blends are called calcium tolerant surfactant blends if they pass the test set out hereinafter. Thus, it may be advantageous if the blend made in step (b) is calcium tolerant according to the test hereinbefore described. However, the invention may also be of use for washing with soft water, either naturally occurring or made using a water softener. In this case, calcium tolerance is no longer important and blends other than calcium tolerant ones may be used.
Calcium-tolerance of the surfactant blend is tested as follows:
The surfactant blend in question is prepared at a concentration of 0.7 g surfactant solids per litre of water containing sufficient calcium ions to give a French hardness of 40 (4×10 −3 Molar Ca 2+ ). Other hardness ion free electrolytes such as sodium chloride, sodium sulphate, and sodium hydroxide are added to the solution to adjust the ionic strength to 0.05M and the pH to 10. The adsorption of light of wavelength 540 nm through 4 mm of sample is measured 15 minutes after sample preparation. Ten measurements are made and an average value is calculated. Samples that give an absorption value of less than 0.08 are deemed to be calcium tolerant.
Examples of surfactant blends that satisfy the above test for calcium tolerance include those having a major part of LAS surfactant (which is not of itself calcium tolerant) blended with one or more other surfactants (co-surfactants) that are calcium tolerant to give a blend that is sufficiently calcium tolerant to be usable with little or no builder and to pass the given test. Suitable calcium tolerant co-surfactants include SLES 1-7EO, and alkyl ethoxylate non-ionic surfactants, particularly those with melting points less than 40° C. Calcium tolerant blends are already well known in the literature and it is not necessary to repeat all possible combinations here. In a further refinement of the surfactant system it has been found that calcium tolerant LAS systems formed by the addition of SLES or High chain-length nonionic often require use of a third surfactant to more closely match the cleaning performance of fully built detergent systems. Suitable third surfactants include betaines, amine oxides, and cationics, such as the Praepagen® materials from Clariant.
A LAS SLES surfactant blend has a superior foam profile to a LAS Nonionic surfactant blend and is therefore preferred for hand washing formulations requiring high levels of foam. SLES may be used at levels of up to 30%.
Addition of a nonionic surfactant (5-20%) to LAS changes the behaviour of the surfactant blend in the dryer. This gives a surprising increase in throughput. Nonionic 7EO may be used at levels of between 5 and 20% based on dry surfactant. NI 30EO may be used at levels of up to 20%.
Material Characteristics of the Surfactant Blends
To enable sufficient Calcium tolerance for LAS blends an additional surfactant material such as SLES or Nonionic surfactant is added. The level that needs to be added to achieve calcium tolerance for the LAS rich blend varies according to the exact surfactant system but the effect can easily be tested to arrive at a suitable level for calcium tolerance. The added non-LAS surfactants should also be liquid-like and not exceed 50 wt % of the total surfactant, the balance of surfactant being LAS. Preferred added surfactants are selected from Nonionic 7EO and/or Nonionic 30EO and/or SLES and/or PAS.
The structuring of the surfactant blend is done by the LAS. This eliminates the need for the usual inorganic structurant, such as silicate. However, such an approach is found to require the surfactant blend to be dried to very low moisture contents of at most 2 wt %, preferably at most 1.5 wt %, more preferably at most 1.2 wt % and most preferably at most 1 wt %. At these moisture levels, a high active mixed surfactant detergent particle with dimensional integrity and free flowing behaviour can be extruded. Where calcium tolerance is not critical it is technically possible to use some soap to further structure the extrudates. Up to 30 wt % soap may be added to the evaporator or dryer, but it is preferred to keep the amount of soap lower: below 20 wt %, more preferably below 10 wt %, most advantageously zero when calcium tolerance is needed.
Increasing the nonionic content within the LAS rich surfactant blend reduces the hardness of the dried blend. Hardness is also related to moisture content of the dried blend. The maximum nonionic level that can be included is about 20%, above this the dried blend is too soft to mill before the extruder, or cut after the extruder. The minimum inclusion level of nonionic in a LAS/nonionic binary blend is about 5%.
A preferred detergent composition has a LAS/SLES surfactant blend. However, the replacement of 20% of the LAS with PAS results in a product with improved storage stability and a similar cleaning profile.
Processing
Blending
The surfactants are mixed together before being input to the drier. Conventional mixing equipment is used.
Drying
To achieve the very low moisture content of the surfactant blend, scraped film devices may be used. A preferred form of scraped film device is a wiped film evaporator. One such suitable wiped film evaporator is the “Dryex system” based on a wiped film evaporator available from Ballestra S.p.A. Alternative drying equipment includes tube-type driers, such as a Chemithon Turbo Tube® drier, and soap driers.
Chilling and Milling
The hot material exiting the scraped film drier is subsequently cooled and broken up into suitable sized pieces to feed to the extruder. Simultaneous cooling and breaking into flakes may conveniently be carried out using a chill roll. If the flakes from the chill roll are not suitable for direct feed to the extruder then they can be milled in a milling apparatus and/or they can be blended with other liquid or solid ingredients in a blending and milling apparatus, such as a ribbon mill. Such milled or blended material is desirably of particle size 1 mm or less for feeding to the extruder.
It is particularly advantageous to add a milling aid at this point in the process. Particulate material with a mean particle size of 10 nm to 10 μm is preferred for use as a milling aid. Among such materials, there may be mentioned, by way of example: Aerosil®, Alusil®, and Microsil®.
Extruding and Cutting
The extruder provides further opportunities to blend in ingredients other than surfactants, or even to add further surfactants. However, it is generally preferred that all of the anionic surfactant, or other surfactant supplied in admixture with water; i.e. as paste or as solution, is added into the drier to ensure that the water content can then be reduced and the material fed to and through the extruder is sufficiently dry. Additional materials that can be blended into the extruder are thus mainly those that are used at very low levels in a detergent composition: such as fluorescer, shading dye, enzymes, perfume, silicone antifoams, polymeric additives and preservatives. The limit on such additional materials blended in the extruder has been found to be about 10 wt %, but it is preferred for product quality to be ideal to keep it to a maximum of 5 wt %. Solid additives are generally preferred. Liquids, such as perfume may be added at levels up to 2.5 wt %, preferably up to 1.5 wt %. Solid particulate structuring (liquid absorbing) materials or builders, such as zeolite, carbonate, silicate are preferably not added to the blend being extruded. These materials are not needed due to the self structuring properties of the very dry LAS-based feed material. If any is used the total amount should be less than 5 wt %, preferably less than 4 wt %, most preferably less than 3 wt %. At such levels no significant structuring occurs and the inorganic particulate material is added for a different purpose, for instance as a flow aid to improve the feed of particles to the extruder.
The output from the extruder is shaped by the die plate used. The extruded material has a tendency to swell up in the centre relative to the periphery. We have found that if a cylindrical extrudate is regularly sliced as it exits the extruder the resulting shapes are short cylinders with two convex ends. These particles may be described as oblate spheroids. This shape is pleasing visually and its slightly rounded appearance also contributes to improved flow properties of the extruded particles in bulk.
Coating
An advantageous variant of the process takes the sliced extruded particles and coats them. This allows the particles to be coloured easily. It also further reduces the stickiness to a point where the particles are free flowing. In this coated state, they can be used without any need for separation by base powder or other solid diluents. The extruded and cut particles are hard and relatively non-sticky when fresh, but the surfactant mix makes them hygroscopic so they would tend to become sticky over time and should be stored away from moisture. Coating makes them more suitable for use in detergent compositions that may be exposed to high humidity for long periods.
By coating such large extruded particles the thickness of coating obtainable by use of a coating level of say 5 wt % is much greater than would be achieved on typically sized detergent granules (0.5-2 mm diameter sphere).
The extruded particles can be considered as oblate spheroids with a major radius “a” and minor radius “b”. Hence, the surface area(S) to volume (V) ratio can be calculated as:
S V = 3 2 b + 3 b 4 ∈ a 2 ln ( 1 + ∈ 1 - ∈ ) mm - 1
When ε is the eccentricity of the particle.
For optimum dissolution properties, this surface area to volume ratio must be greater than 3 mm −1 . However, the coating thickness is inversely proportional to this coefficient and hence for the coating the ratio “Surface area of coated particle” divided by “Volume of coated particle” should be less than 15 mm −1 .
By using the process of the invention, a more effective coating can be obtained at a lower level of coating material. Although any known coating may be used, for instance organic, including polymer, or inorganic coating it is particularly advantageous to use an inorganic coating deposited by crystallisation from an aqueous solution as this appears to give positive dissolution benefits and the coating gives a good colour to the detergent particle, even at low deposition levels. An aqueous spray-on of the coating solution in a fluidised bed has been found to give good results and may also generate a slight rounding of the detergent particles during the fluidisation process.
Suitable inorganic coating solutions include sodium carbonate, possibly in admixture with sodium sulphate, and sodium chloride. Food dyes, shading dyes, fluorescer and other optical modifiers can be added to the coating by dissolving them in the spray-on solution or dispersion. Use of a builder salt such as sodium carbonate is particularly advantageous because it allows the detergent particle to have an even better performance by buffering the system in use at an ideal pH for maximum detergency of the anionic surfactant system. It also increases ionic strength, which is known to improve cleaning in hard water, and it is compatible with other detergent ingredients that may be admixed with the coated extruded detergent particles. If a fluid bed is used to apply the coating solution, the skilled worker will know how to adjust the spray conditions in terms of Stokes number and possibly Akkermans number (FNm) so that the particles are coated and not significantly agglomerated. Suitable teaching to assist in this may be found in EP1187903, EP993505 and Powder technology 65 (1991) 257-272 (Ennis).
Another coating technique that may be used is to first dry-coat the extruded particle surface with a layer of electrolyte with mean diameter less than 100 μm using a simple drum-type mixer and subsequently to use an aqueous spray to harden this layer. Drying and/or cooling may be needed to finish the process. The aqueous spray may be replaced by an organic melt using a high melting point nonionic surfactant or nonionic material. In this case, no drying is necessary but cooling may be needed.
It will be appreciated by those skilled in the art that multiple layered coatings, of the same or different coating materials, could be applied, but a single coating layer is preferred, for simplicity of operation, and to maximise the thickness of the coating. The amount of coating should lay in the range 3 to 50 wt % of the particle, preferably 20 to 40 wt % for the best results in terms of anti-caking properties of the detergent particles.
The Extruded Particulate Detergent Composition
Whether coated or uncoated the particles dissolve easily in water and leave very low or no residues on dissolution, due to the absence of insoluble structurant materials such as zeolite. When they are coated, the particles have an exceptional visual appearance, due to the smoothness of the coating coupled with the smoothness of the underlying particles, which is also believed to be a result of the lack of particulate structuring material in the extruded particles.
The invention will now be further described by way of example only.
In the examples, the following nomenclature is used:
LAS—means neutralised LAS acid (LABSA) LAB—means the “linear” alkylate LABSA—means LAS acid. PAS—means primary alkyl sulphate SCMC—Sodium carboxymethyl cellulose SLES (XEO)— means sodium lauryl ether sulphate (X Moles Average Ethoxylation)
Test parameters used in the examples are defined and determined in accordance with the following:
Unconfined Compression Test (UCT)
In this test, freshly produced detergent composition was compressed into a compact and the force required to break the compact was measured. The detergent composition was loaded into a cylinder and the surface levelled. A 50 g plastic disc was placed on top of the detergent composition and a 10 kg weighted plunger was placed slowly on top of the disc and allowed to remain in position for 2 minutes. The weight and plunger were then removed and the cylinder removed carefully from the detergent composition to leave a free-standing cylinder of detergent composition with the 50 g plastic disc on top of it. If the compact were unbroken, a second 50 g plastic disc was placed on top of the first and left for approximately ten seconds. Then if the compact were still unbroken, a 100 g disc was added to the plastic discs and left for ten seconds. Then the weight was increased in 250 g increments at 10 second intervals until the compact collapsed. The total weight needed to effect collapse was noted.
For freshly made detergent composition tested under ambient temperature conditions, the cohesiveness of the detergent composition was classified by the weight (w) as follows, (assuming the standard 10.0 kg compaction load is used).
w < 1 kg Good flowing. 1 kg < w < 2 kg Moderate flowing. 2 kg < w < 5 kg Cohesive. 5 kg < w Very cohesive.
Dynamic Flow Rate (DFR)
Dynamic Flow Rate (DFR) in ml/sec. was measured using a cylindrical glass tube having an internal diameter of 35 mm and a length of 600 mm. The tube was securely clamped with its longitudinal axis vertical. Its lower end was terminated by means of a smooth cone of polyvinyl chloride having an internal angle of 15 DEG and a lower outlet orifice of diameter 22.5 mm. A beam sensor was positioned 150 mm above the outlet, and a second beam sensor was positioned 250 mm above the first sensor.
To determine the dynamic flow rate of a detergent composition sample, the outlet orifice was temporarily closed, for example, by covering with a piece of card, and detergent composition was poured into the top of the cylinder until the detergent composition level was about 100 mm above the upper sensor. The outlet was then opened and the time t (seconds) taken for the detergent composition level to fall from the upper sensor to the lower sensor was measured electronically. The DFR is the tube volume between the sensors, divided by the time measured.
Bulk Density (BD)
“Bulk density” means the bulk density of the whole detergent composition in the uncompacted (untapped) aerated form. It was measured by taking the increase in weight due to filling a 1 litre container with the detergent composition.
Equilibrium Relative Humidity (ERH)
Water activity (usually given the parameter Aw) is related to equilibrium relative humidity (% ERH) by the equation:
ERH=100 ×Aw
Aw=equilibrium partial pressure of moisture/saturation partial pressure of moisture at that temp.
A value for water activity of 1 (ERH=100) indicates pure water, whereas zero indicates total absence of water.
EXAMPLE 1
Surfactant raw materials were mixed together to give a 67 wt % active paste comprising 56.5 parts LAS, 15.2 parts PAS and 28.3 parts SLES.
Raw Materials used were:
LABSA
Caustic
(48% Solution)
PAS
SLES (3E0)
Stepan BES70
The paste was pre-heated to the feed temperature and fed to the top of a wiped film evaporator to reduce the moisture content and produce a solid intimate surfactant blend, which passed the calcium tolerance test. The conditions used to produce this LAS/PAS/SLES blend are given in Table 1.
TABLE 1
Jacket Vessel Temp.
80
° C.
Feed
Nominal Throughput
65
kg/h r
Temperature
70
° C.
Density
1.2
kg/l
Product
Moisture (KF*)
1.0%
Free NaOH
0.16%
*analysed by Karl Fischer method
On exit from the base of the wiped film evaporator, the dried surfactant blend dropped onto a chill roll, where it was cooled to less than 30° C.
After leaving the chill roll, the cooled dried surfactant blend particles were milled using a hammer mill, 2% Aerosil® was also added to the hammer mill as a mill aid. The resulting milled material is hygroscopic and so it was stored in sealed containers. Its properties are given in table 2.
TABLE 2
Phys Props
Particle size
UCT
DFR
BD
D (50)
>180 μm
>1400 μm
ERH
kg
ml/s
g/l
μm
(%)
(%)
8.7
1.9
70/71
558
342.97
33.0
3.38
The cooled dried milled composition was fed to a twin-screw co-rotating extruder fitted with a shaped orifice plate and cutter blade.
The average particle diameter and thickness of samples of the extruded particles were found to be 4.46 mm and 1.13 mm respectively. The standard deviation was acceptably low.
The particles were then coated using a Strea 1 fluid bed. The coating was added as an aqueous solution and coating completed under conditions given in Table 3. Coating wt % is based on weight of the coated particle.
TABLE 3
Target coating Level
5 wt %
10 wt %
15 wt %
Mass Solid [kg]
1.25
1.25
1.25
Coating Solution
Sodium
Sodium
Sodium
Carbonate
Carbonate
Carbonate
(25%)
(25%)
(25%)
Dye (0.1%)
Dye (0.1%)
Dye (0.1%)
Mass Coating Solution [kg]
0.263
0.555
0.882
Air Inlet Temperature [° C.]
80
80
80
Air Outlet Temperature [° C.]
42
40
41
Coating Feed Rate [g/min]
14
15
15
Coating Feed temperature
38
41
40
[° C.]
As can be seen from Table 3 the samples have different coating levels. These samples and additional samples made using the same process were then equilibrated at 48 and 65% relative humidity and their hardness measured. The hardness measurements are shown in Table 4.
TABLE 4
Coating
Average Hardness
Average Hardness
Level
@20° C./48% RH
@21° C./65% RH
(%)
(MPa)
(MPa)
5
0.07
0.03
10
0.19
0.06
15
0.40
0.22
25
0.85
0.59
EXAMPLE 2
Surfactant mixtures were selected based on their expected calcium-tolerance under typical wash conditions. For this example, two LAS and nonionic surfactant blends were prepared.
Example 2.1LAS/NI-7EO=76.9/23.1 Ratio Example 2.2LAS/NI-7EO=83.3/16.7 Ratio
The blends were manufactured as pumpable lamellar liquid crystal feedstocks containing ca. 70% total surfactant and 30% water. These feedstock blends were fed to a wiped film evaporator and dried.
Properties of the dried surfactant blends leaving the wiped film evaporator are given in Table 5.
TABLE 5
Example #
2.1
2.2
Jacket Vessel Temp. ° C.
84
92
Feed
Nominal Throughput kg/hr
30
45
Temperature ° C.
71
75
Density kg/l
0.94
1.01
Product
% Moisture(KF)
0.9
1.3
Free NaOH %
—
—
Each of these dried surfactant blends was milled using a hammer mill, 2% Aerosil® was added as a mill aid. The resulting dried material is hygroscopic and so was stored in sealed containers. Properties are given in Table 6.
TABLE 6
Physical Props
% >1400
ERH
UCT
DFR
BD
D (50)
% >180
(sieved)
2.1
Too cohesive for measurements
668
14.0
28.3
2.2
8.7
400
103
515
376
30.0
11.8
Dried blend 2.1 was found to be too cohesive to feed to the extruder used in example 1 and falls outside the scope of the invention. Dried blend 2.2 was extruded satisfactorily using the process described in Example 1. It should be noted here that in order to incorporate nonionic even at the levels successfully done in 2.2 it is essential to co-dry the LAS and the nonionic to form a molecular dispersion of the surfactants. Any attempt to blend the surfactants in the extruder leads to extrusion of a sticky mess unless high levels of solids are also used.
The extruded particles formed from dried blend 2.2 were coated as in Example 1 above.
EXAMPLE 3
A mixture of LAB ex Huntsman, nonionic and PEG in the ratio 100:10:2 was sulphonated at pilot plant scale to convert the LAB to LABSA and then neutralised with caustic solution to make the LABSA into LAS.
The only moisture added to the system was contained in the 50% sodium hydroxide solution (low chloride) used as the neutralisation agent. Details of the materials are as specified in table 7. The neutralisation reaction on the LABSA, (Linear Alkyl Benzene Sulphonic acid) was completed in the presence of nonionic and PEG. An 85 w % active paste comprising anionic surfactant, nonionic and PEG that could be pumped with a vane pump was produced. The neutralisation process was continued for 8 hours.
TABLE 7
Raw Material
Supplier/Trade name
% Active
PEG 4000
BP Chemicals
100
Linear Alkyl
Huntsman/A225
98-100
Benzene, (LAB)
Nonionic 7EO
Shell Chemicals/Neodol 25-7
100
Caustic soda
Univar
50
The paste surfactant mixture was dried in a Turbo-Tube Dryer and milled using a hammer mill: no mill aid was added. The properties of the resulting dried milled composition are given in Table 8.
TABLE 8
Analysis
Result
ERH %
6.4
Moisture Content %
0.6
Hardness MPa
18.6
T90 s
69
Bulk Density (BD) g/l
587
Dynamic Flow Rate (DFR) ml/s
105
UCT
FAIL
Particle Size d(10) μm
173
Particle Size d(50) μm
570
Particle Size d(90) μm
941
T90=time in seconds for change in the water conductivity to reach 90% of its final magnitude when a 250 mg sample is placed into 500 ml of stirred demineralised water at 25° C.
The dried and milled composition was fed to a twin screw extruder and extruded. The average maximum thickness of the extruded particles was 1.13 mm (sd 0.18) and their average particle diameter was 4.46 mm (sd 0.26).
The particles are coated as in example 1.
EXAMPLE 4
Uncoated extruded particles from example 3 were coated using a coating level of 15 wt %. This was achieved by spraying a 25 wt % sodium carbonate solution, containing 0.5 wt % orange dye, into a fluid bed and evaporating off the excess moisture. The high active extruded particles being coated are hygroscopic and temperature sensitive. Thus, at all times a balance was maintained between the spray rate and evaporation rate of the solution and the temperature of the bed. The fluidised bed is operated as known to the skilled worker in order to avoid agglomeration of the material. The coating conditions used are given in table 9.
TABLE 9
Analysis
Result
Solid Mass
1.5
kg
Air Inlet Temperature
80°
C.
Air Outlet temperature
35°
C.
Spray Rate
22
g/min
Spray Temperature
40°
C.
EXAMPLE 5
Conventional detergent base powder containing sodium linear alkyl sulphonate (LAS) as surfactant and sodium tripolyphosphate as builder was dry mixed with uncoated extruded particles made according to the first part of the process of example 1 and using a blend of LAS/PAS/SLES with ratio 58.3/14.6/27. The extruded particles used had a circular cross section with average diameter 5 mm and average maximum thickness 1 mm.
The mixtures of detergent powder and extruded particles were sealed in conventional unlaminated cardboard packs and stored at 28° C. and 70% Relative Humidity for 4 weeks. Packs were examined periodically to determine how much caking had occurred by pouring the product from the pack onto a tray and visually estimating the percentage of lumped powder. Examples 5A, 5B and 5C in Table 10 correspond to extruded particle levels of 0, 20 and 40% by weight based on the combined weight of particles and powder.
The results in Table 10 show that powders containing up to and including 20 wt % uncoated extruded particles according to the invention are storage stable, but above that level and at some point below 40 wt % extruded particles, the mixture with base powder becomes unstable on storage.
TABLE 10
Weight % of
Caking ex-pack
Caking ex-pack
Example
extrudates in pack
week 2
week 4
5A
0
<25%
<50%
5B
20
<25%
<50%
5C
40
>75%
>75%
Similar results are obtained with base powders including zeolite and/or carbonate in place of the sodium tripolyphosphate.
EXAMPLE 6
100 parts of the milled material produced in example 1 at the exit of the mill was mixed in a tumbling mixer with 1.15 parts fluorescer and 3 parts SCMC. This mixture was then fed to a twin-screw co-rotating extruder along with 1.15 parts perfume liquid. The resulting mixture was extruded through a shaped orifice plate and cut with a cutter blade to produce detergent particles comprising just under 4 wt % perfume, fluorescer and SCMC in addition to surfactant.
The extruded particles were determined to have an average thickness of 1.11 mm (sd 0.18) range 0.9 to 1.4. The T90 dissolution time was 73 seconds.
Caking on extended storage was acceptable after coating. The material was sealed in conventional unlaminated cardboard packs and stored at 28° C. and 70% relative humidity for 8 weeks. Packs were examined during this period for acceptable powder flow properties/caking by pouring the product from the pack onto a tray and visually estimating the percentage of lumped powder. Results are given in Table 11.
TABLE 11
Pack Sample
Flow
Residue in Pack
Lumps ex pack
Coated
Satisfactory
25-50%
25%
Uncoated
No flow
100%
100%
EXAMPLE 7
This example shows that the superior appearance of the extruded particles is due to the uncoated particle being smoother than conventional detergent particles and the final surface being smoother still. This need for the underlying surface to be smooth before a coating is applied is known generally but it was nevertheless surprising just how improved the coated particles appear compared with other conventional detergent particles. The underlying smoothness of the extruded particles is thought to be assisted by their not containing solid structuring materials, unlike prior art extruded particles. The particles are also superior in appearance when compared to prior art granules made by other processes.
In order to determine the value of Ra (average surface roughness) for each particle sample we used a non contact optical profilometer equipment comprising a low powered near-infrared Laser Stylus mounted on a moveable stage controlled by a computer. A Laser stylus is a displacement transducer based on technology found in a compact disc player. In a compact disc player, a focussed laser is used to record the pits embedded within the disk. Since the disk wobbles slightly as it spins, an auto-focus mechanism is needed to maintain the in-focus condition. This auto-focus mechanism uses the light reflected from the disc to generate an error signal that can be used to lock the laser onto the surface. The error signal is minimised through the real-time adjustment of a lens position, and a feedback loop to achieve an acceptable response time.
To use such a device to measure surface topography requires the laser to be focussed on the surface, and then the surface moved in a raster fashion (line scan Y and step scan X) underneath it. A recording of the lens position gives a measurement of the surface height variation.
The major component of the Laser Profilometer is a laser displacement transducer (Rodenstock Laser Stylus RM 600 LS10) which operates in the near-infrared at 780 nm. This transducer gives a spot size of about 1.3 μm on the measured surface, has a distance resolution of 1 nm and an operational range of ±400 μm. The ‘stand-off’ distance between the end of the transducer and the measured surface is about 10 mm, in air, and the full included cone angle of the focused beam is approximately 47°. This transducer is an example of an ‘optical follower’ that utilises auto-focusing optics to ‘lock-onto’ an interface and to measure its location relative to a reference position internal to the device.
Ra (average surface roughness) is one of the most effective surface roughness measures and is commonly adopted in general engineering practice. It gives a good general description of the height variations in the surface. A mean line is first found that is parallel to the general surface direction and divides the surface in such a way that the sum of the areas formed above the line is equal to the sum of the areas formed below the line. The surface roughness Ra is now given by the sum of the absolute values of all the areas above and below the mean line divided by the sampling length.
The test sample is mounted on the stage to reflect the laser. The sample is held sufficiently firmly to prevent any spurious movement during scanning.
Data is evaluated on a computer where programs flatten the topography, line by line, to leave deviations net of tilt and curvature. Ra is the mean roughness of the measured surface heights of a sample.
Because some of the original sample particles proved to be insufficiently reflective for the profilometer instrument to be able to lock onto the surface, we made surface replicates of all three test particles using a material called Silflo (Ex-Flexico), which is a light-bodies silicone rubber impression material that readily flows into surface features. The material was prepared and then a coated particle was pushed (gently) into the rubber before it hardened. On removing the particle, a surface replicate is left in the Silflo.
We then placed this replicate impression into the laser profilometer and measured a section, up to 1000 μm by 1000 μm, with data taken every μm in both x and y directions. For each type of particle, we measured multiple replicates in this way. Results are given in Table 12. The details of the original particles are given below.
Extruded particles were made according to the first part of the process of example 1 and using a blend of LAS/PAS/SLES with ratio 58.3/14.6/27. The extruded particles had a circular cross section and dimensions of about 5 mm diameter by 1 mm.
A fraction of these extruded particles was coated using a 25% sodium carbonate coating solution to give a final coating level of 30 wt %.
The conventional High active granule was made using the process described in WO2002/24853 and had the composition:
LAS
65.5%
Soda Ash
11.5%
Zeolite
17.9%
Sodium Sulphate
2.2%
Water and minors
balance
To be as good a comparison as possible with the larger extruded particles we used an oversized granule (retained on a 1.18 mm sieve). Even so, due to this being smaller than the extruded particles, we could only measure a 500 μm by 500 μm segment.
TABLE 12
Ra (μm)
Ra (μm)
Ra (μm)
High Active Granule
18.020
21.732
—
uncoated extruded particles
7.611
6.439
6.371
coated extruded particles
5.384
2.610
3.116
It can be seen from table 12 that a conventional high active granule detergent particle is much rougher than the uncoated extruded particle and that when coated the extruded particle is smoother still. Ra (μm) of less than 6, even less than 4, was achieved for the coated extruded particles. The combination of larger radius of curvature, smooth base particle and coating gives the coated extruded particle a stunning appearance when compared to the typical appearance of a detergent particle. When coupled with a low particle size distribution this leads to a dramatically visually different and enticing particle that consumers would really appreciate is different from their normal product.
|
A process for manufacturing detergent particles comprising the steps of: a) forming a liquid surfactant blend comprising a major amount of surfactant and a minor amount of water, the surfactant part consisting of at least 51 wt % linear alkylbenzene sulfonate and at least one co-surfactant, the surfactant blend consisting of at most 20 wt % nonionic surfactant; b) drying the liquid surfactant blend of step (a) in an evaporator or drier to a moisture content of at most 2 wt % and cooling the output from the evaporator or dryer; c) feeding the cooled material, which output comprises at least 93 wt % surfactant blend with a major part of LAS, to an extruder, optionally along with less than 10 wt % of other materials such as perfume, fluorescer, and extruding the surfactant blend to form an extrudate while periodically cutting the extrudate to form hard detergent particles with a diameter across the extruder of greater than 2 mm and a thickness along the axis of the extruder of greater than 0.2 mm, provided that the diameter is greater than the thickness; d) optionally, coating the extruded hard detergent particles with up to 30 wt % coating material selected from powdered inorganic material and mixtures of such material and nonionic material with a melting point in the range 40 to 90° C.
| 2
|
The invention relates to a circuit arrangement for separating the colour difference signal components of a PAL colour television signal, in which the composite chrominance signal is applied through a first path and a second path delayed by substantially one line period or an integral multiple thereof relative to the first path to respective inputs of a combining stage, particularly an adder or a subtracting stage, from whose outputs the separated signals can be derived.
BACKGROUND OF THE INVENTION
Because of the line structure of the television picture such a television signal is essentially assembled from components which are spaced by the line frequency f h of, for example, 15,625 Hz. The brightness signal consists of such components which start at zero and which may reach to the resolution limit at for example 5 MHz. The two components u and v of the chrominance differential signal which correspond to the blue and the red colour difference signal are located at the line frequency distance above and below the chrominance signal subcarrier frequency f o . The u-components are located on either side of the chrominance signal subcarrier at a distance f h ; in contrast therewith the v-components are shifted by half the line frequency f h .
It is known to separate the u- and v-components by means of a decoding arrangement of a comb filter type. To this end the composite signal which contains at least the chrominance signal components is applied to a combining stage, on the one hand directly and on the other hand via a delay device. It is, for example, possible to obtain the u-chrominance signal in a substracting combining stage, when the chrominance signals are delayed in the delay device by a time period corresponding to 283.5 periods of the chrominance signal subcarrier f o and to obtain the v-chrominance signal in an adding combining stage. In a device which produces a time delay of 283.5 periods a total delay of 63.9433 μs is obtained. It is alternatively possible to use a device which produces a delay of 284 chrominance signal subcarrier oscillations, which correspond to 64.056 μs; the above-mentioned signals are then obtained at the other combining stage, that is to say the u-signal is obtained at the adder stage and the v-signal at the subtracting stage.
With a standardised PAL-colour television signal the subcarrier frequency is not a multiple of the line frequency, but it holds in accordance with the European standard that:
f.sub.o =283,75 f.sub.h +f.sub.v ( 1).
When the vertical deflection frequency f v is 25 Hz, then:
f.sub.o =283,7516 f.sub.h =4,43361875 MHz (2).
The maxima and minima of the transmission curves 1, shown in FIG. 1, which are formed by the comb filter properties are defined, in dependence on the frequency f, by the formula:
A˜| sin π·(283,5/f.sub.o)·f|(3).
The maxima are located in the position where the sine is equal to (k+1/2)π;
the minima are found at k π, wherein k is an integer.
The frequency f x , at which the maximum of the transmission curve occurs, and the frequency f n , at which the minimum of the transmission curve occurs are found with the above-mentioned values for the chrominance signal subcarrier f o and the delay by 283.5 chrominance subcarrier periods at
f.sub.x =(k+1/2)(283.7516/283,5)f.sub.h and (4)
f.sub.n =k·(283,7516/283,5)·f.sub.h, respectively (5)
From these formulae it appears that the period of the extremes of the transmission curve 1 do not accurately correspond with a muliple of the line frequency f h . So, when it is ensured, in accordance with the above-indicated customary dimensioning that the extreme values of the transmission curve 1 in the vicinity of the chrominance signal subcarrier correspond substantially exactly with the components of the colour difference signals u and v, a deviation occurs at a somewhat greater frequency distance. As far as the maxima are concerned this is hardly noticeable, as the tops of the sine waves change their value only little at small shifts. At the minima which correspond to the steep edges of the half sine waves the changes are more considerable, but these must be put up with.
FIG. 1 shows portions of the transmission curve along an abscissa, which is divided into sections and scaled in multiples of the frequency f, divided by the line frequency f h . The expanded curve 1 was obtained by means of a device producing a time delay of 283.5 periods of the chrominance subcarrier f o , the output signals of this device being combined with the undelayed signal in a subtracting stage. Above this curve there are shown by means of short upward lines on a horizontal line the u-frequency components of the chrominance signal, while the v-frequency components are represented by downward lines. These components are spaced by a frequency distance which is equal to the line frequency.
When the above-mentioned delayed and the undelayed signals are applied to an adder stage a transmission curve 2 which is defined by the formula:
A˜| cos π283.5 f/f.sub.o |,
is obtained, which varies in accordance with the broken line curve shown in FIG. 1. It is shown that in the region of the chrominance subcarrier f o , the u-components are located at the maxima of the expanded curve 1 and the v-components at the maxima of the broken-line curves 2. For components which are further away from the chrominance sub-carrier, for example at 211 f/f h which corresponds to a modulation frequency of 1.14 MHz, there are small shifts with respect to the assigned maximum, which, however, have no effect on filtering of the said modulation components.
Each time the other modulation component is found on these comb filter transmission curves 1 and 2 in the vicinity of the chrominance subcarrier f o in the range of the peaks of minimum transmission, so that these components are removed by filtering to a considerable extent. For frequencies which are located at a greater distance, for example at the abscissa value 211, which corresponds to 1.14 MHz there is a certain shift of the peaks to the left, so to the lower frequency value, so that then the suppression of each time the other frequency component is not absolute. This is however put up with.
The components of the brightness signals correspond to the abscissa values shown in FIG. 1. These values are located at the edges of the sine and cosine tops, repsectively, of the transmission curves 1 and 2 in such manner that they are somewhat attenuated. As the higher frequency components of the brightness signal have only a rather low energy content and as they are often additionally reduced by an IF-drop in the vicinity of the chrominance subcarrier, the resultant disturbances may be put up with.
Experiments performed showed however that for the circuit arrangement described so far, which produces output signals corresponding to the transmission curves 1 and 2, the minima of the transmission curve 2 move at lower frequencies away from the brightness components and that in a corresponding manner the maxima of the transmission curve 2 move towards the brightness components. This means that in the separated v-chrominance signal the brightness components of, for example, 3.5 MHz and less come through stronger than the brightness components in the range of the chrominance subcarrier frequency f o of 4.43 Mhz. As furthermore the lower-freqency brightness components have also a higher energy content, they may produce clearly perceptible disturbances in the chrominance signal.
The invention has for its object to provide a circuit arrangement of the type defined in the preamble of such a construction that in the two separated chrominance signal components the lower-frequency brightness signal contents are suppressed better than in the vicinity of the chrominance signal subcarrier.
SUMMARY OF THE INVENTION
According to the invention this object is accomplished in that the delayed signal applied to the first combining stage and the delayed signal applied to the second combining stage are delayed relative to each other.
Preferably, the delayed signals applied to the combining stages are delayed relative to each other by an odd multiple of half a chrominance subcarrier period.
If the output signal is further transmitted in time-division multiplex form, one single combining stage is sufficient, when the delayed signal alternately is taken from the output of the first or of the second delay line by means of a change-over switch which is periodically operated in the ryhythm of a multiple of the chrominance subcarrier frequency, for example double said frequency, and applied to the combining stage.
When in accordance with the invention the delayed signal is applied via, a possibly further, delay unit to the second combining stage, which then operates in the subtacting mode, in such manner that the signal is delayed by an additional half cycle, so for the above-mentioned example by 284 chrominance subcarrier periods, a transmission curve 3, 4 defined by the formula
A˜| sin π284·(f/f.sub.o)|,
is obtained, whose half wave has a somewhat shorter period compared with the half wave shown by means of the broken lines in FIG. 1 and which transmission curve 3, 4 therefore appears to have been compressed and more or less shifted in the direction of the chrominance subcarrier frequency f o . This shift is not noticeable in the region of the chrominance subcarrier f o . In FIG. 1, portions 3 and 4, respectively, of this altered transmission curve are shown by means of dotted lines at the abscissa values 211 and 70. It appeared that at this transmission curve 3 the spectrum component 211 of the brightness signal is now located at a lower ordinate value and is therefore attenuated to a greater extent than in accordance with the broken-line curve 2. This is still more noticeable at the abcissa value 70 which assumes a particularly low value at the curve 4, which is represented there by a dotted line. Thus, in accordance with the invention, the components of the brightness signal are properly filtered from the two chrominance signals u and v, the separation of the chrominance signals substantially not having deteriorated.
As regards the frequency above the chrominance subcarrier frequency f o , for example at the abscissa value 320 which corresponds to 5 MHz, the dotted curve 5 has been shifted so in a circuit arrangement of the invention that the brightness component is attenuated to a lesser degree. However, this range is without any significance for actual practice, as here the average energy contents of the brightness components is so small that it may be neglected, particularly after a customary drop in the IF-stage of a television receiver, so that no additional disturbances are produced in the chrominance signal.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be further described by way of non-limitative example with reference to the accompanying drawing, in which
FIGS. 2, 3, 4 and 5 show different embodiments of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 2 shows schematically a circuit arrangement of the invention. The input to terminal 20 is the composite chrominance signal F, which in orthogonal modulation contains the component u and the component v, whose sign changes from line to line, is applied to a first subtracting stage 23 via a first delay device 21 and also to a second subtracting stage 24 via a second delay device 22, and, in addition, directly to the two subtracting stages 23 and 24. The first delay device, for example a known glass delay line, produces a delay of 283.5 chrominance subcarrier periods, and the second delay device 22, for example a glass delay line as well, produces a delay of 284 chrominance subcarrier periods. From the output of the subtracting stage 23 a s9ignal is then obtained on output terminal 25 according to the transmission characteristic of the expanded curve 1 of FIG. 1 which consequently results in the u-components from which the v-content has been eliminated. In a corresponding manner there is obtained at the output terminal 26 a signal according to the broken-line portions 3, 4 and 5 of the transmission curve shown in FIG. 1 which consequently results in the v-components from which the u-content has been eliminated.
It is preferable to use instead of the delay devices 21 and 22 a delay device as shown in FIG. 3, in which components corresponding with those in FIG. 2 have been given the same reference numerals, it is alternatively possible to achieve the longer time delay by applying the signal, after it has passed through the delay device 21 and before it is applied the subtracting stage 24, to a further delay device 31, which produces a delay of half a chrominance subcarrier period, so that the desired delay by 284 chrominance subcarrier periods is again achieved before it reaches the stage 24.
Particularly when the signals are available in digital form it is possible to effect processing in time-divison multiplex in such manner that at the output the u- and the v-components are transmitted in the same channel at alternate moments. To this end, in accordance with FIG. 4 the composite chrominance signal F is applied from the input terminal 20 to a first delay line 32, which is triggered by a clock pulse generator 33 at four times the chrominance subcarrier frequency and thus delays the signals of one line in 1134 clock pulses by 63.943 μs. The clock pulse generator 33 is triggered from a terminal t with an oscillation of a suitable frequency, preferably four times the chrominance subcarrier frequency.
The delayed signal thus obtained is applied from the output 34 of the first delay line 32 to a first input of a signal selection switch 35 and in addition to a second delay line 36 which produces with the same clock frequency a delay of 2 clock pulses of a total of 0.113 μs, so that at the output a signal is available which has been delayed by a total of 64.056 μs and which is applied to the second input of the signal selection switch 35. The signal selection switch 35 is operated by the clock pulse generator 33 at twice the chrominance subcarrier frequency in such manner that during the period of time in which the chrominance subcarrier oscillation cos(f o ·2π·t) assumes its highest values, the signal which has been delayed by 63.943 μs is transmitted to the subtracting stage 37, and that during the periods of time in which the chrominance subcarrier oscillation cos(2πf o ·t) passes through zero the signal which was delivered by 64.056 μs is transmitted to the subtracting stage 37, to which also the input signal F from terminal 20 is applied. Then the samples of the separated u- and v-components, respectively, of the composite chrominance signal F are alternately available at the output terminal 38, which is connected to the output of the subtracting stage 37, the rhythm of the occurrence of the samples of each component being twice the chrominance subcarrier frequency.
When the clock pulse frequency at which the signal selection switch 35 is operated as well as the sampling frequency are equal to four times the chrominance subcarrier frequency, the sampling pulses may be located, in relation to the chrominance subcarrier, at the four instants at which the signals +u, +v, -u, -v, and +u, -v, -u, +v, occur during alternate line periods respectively. It is then possible to eliminate the sign change which is determined by the modulation of the chrominance subcarrier and to obtain the demodulated signal (U, V) by means of a cross-over switch 39 which periodically interchanges the inputs of the subtracting stage 37 at a rate corresponding to the chrominance subcarrier frequency, so at half the frequency with which the switch 35 is operated. The switch 39 is controlled by a control signal t/2 of the chrominance subcarrier frequency the phase of which is shifted and reshifted at half the line frequency over a period corresponding to a sampling interval. This is shown in FIG. 5, which essentially corresponds to FIG. 4, but in which the cross-over switch stage 39, which preceeds the subtracting stage 37 is drawn with a broken line. Then the demodulated signals U and V are alternately obtained in time-division multiplex at the output 38 of the stage 37.
It is of course possible to extend each of the delayed and undelayed paths with a same additional delay without influencing the delay differences. Such circuits also should be considered to be protected by the claims.
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Circuit arrangement for separating the components of a PAL color television signal, in which the (digitized) u- and v-signals of the subcarrier frequency are passed through two delay lines which produce different time delays (for example 283.5 and 284 chrominance subcarrier periods): an improved cross-talk attenuation from the luminance signal to the chrominance signals in the lower sideband is then obtained.
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FIELD OF THE INVENTION
The invention pertains to testable photoelectric smoke detectors. More particularly, the invention pertains to such detectors wherein a supplemental source of radiant energy and a local monitoring signal are used to create a test condition.
BACKGROUND OF THE INVENTION
Photoelectric smoke detectors have been recognized as being useful in providing signals indicative of concentrations of smoke or particles of combustion in the ambient atmosphere. Such detectors can be used alone or in groups to provide an indication of a developing fire condition.
Known photoelectric smoke detectors often provide circuitry for testing the respective detector. Various types of test circuitry are known.
The graph of FIG. 1 contains 2 curves, i.e. curve A and curve B. The units for smoke concentration and radiation sensor signal appear in arbitrary units; the ranges of values are chosen for illustration.
Curve A depicts a typical photoelectric smoke detector's radiation sensor output as a function of smoke concentration. In the absence of smoke (smoke concentration=0), the radiation sensor generates a nonzero output (shown 0.2) resulting from background reflections of radiation inside the smoke detection chamber. The reflected radiation originates from the internal radiation source, reflects from the inside walls of the chamber, and finally irradiates the radiation sensor to produce a nonzero output.
A known "self test" technique employs a higher radiation sensor amplifier gain during a "self test" mode, so that the amplifier output simulates the presence of smoke within the detection chamber. For example, a "test" gain whose magnitude is greater than "normal mode" gain by a factor of 6 would exceed an alarm threshold corresponding to a smoke concentration of 1 in the absence of smoke. This follows since six times the 0.2 radiation sensor signal yields a signal of 1.2. In "normal mode", the detector requires a smoke concentration of 1.0 to cause a radiation sensor signal of 1.2.
Curve B of FIG. 1 depicts a photoelectric smoke detector's radiation sensor output, when the optics employ a tightly focused laser diode, a radiant energy source, specifically arranged to minimize unwanted background reflections. In the absence of smoke (smoke concentration=0), the radiation sensor generates a zero output, or an output very small in magnitude. Such a small radiation sensor output renders the above described "self test mode" smoke simulation technique problematic or even nonfunctional.
One known solution to the "self test" problem inherent in low background noise photoelectric detectors utilizes a separate "test" radiation source to directly or indirectly irradiate the sensor. Such schemes fail to assess the proper operation of the "normal" radiation source, i.e. the laser diode.
There continues to be a need for circuitry and methods of testing low background noise photoelectric smoke detectors which can also take into account the level of functioning of the radiant energy source for the detector. Preferably, such circuitry could be incorporated into low background noise photoelectric detectors without undue expense and without detracting in any way from the performance of such detectors.
SUMMARY OF THE INVENTION
In accordance with the invention, the proper operation of the laser diode can be verified by using an internal photodiode monitor contained within available commercial laser diode packages. The photodiode monitor internal to such laser diode packages generally provides a signal for active regulation of the laser diode optical output.
Where a laser diode is incorporated as a source of radiant energy into a photoelectric detector, the photodiode monitor signal may also be used to report laser diode status for "self test" and other supervisory purposes. The laser diode monitoring circuit can be used in conjunction with a separate source of radiant energy used to create a test condition.
In accordance with the one aspect of the invention, a photoelectric detector includes: a housing which defines an interior volume; a semiconductor source of radiant energy carried within said housing wherein said source includes an integrally formed self-monitoring circuit and wherein a portion of said circuit is coupled to an accessible conductor; and a separate supervisory circuit with an input port for receipt of control signals wherein said circuit is coupled to the accessible conductor and wherein the circuit provides an output in response to the presence of both a selected signal from said conductor and a selected control signal.
These and other aspects and attributes of the present invention will be discussed with reference to the following drawings and accompanying specification.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a graph illustrating outputs from two types of known photoelectric detectors;
FIGS. 2A, 2B are top and side views respectively, of a detector in accordance with the present invention; and
FIG. 3 is a block diagram of a system, in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
While this invention is susceptible of embodiment in many different forms, there are shown in the drawing, 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 intended to limit the invention to the specific embodiments illustrated.
FIGS. 2A and 2B depict a photoelectric detector 10 in accordance with the present invention. The detector 10 includes an optics housing 12 which defines an internal volume 14, a smoke chamber. The housing 12 is carried on a printed circuit board 16.
A source of radiant energy, a laser diode 20 with integral monitoring circuitry is carried on the housing 12. The source 20 emits a beam of essentially monochromatic radiant energy 22 across the internal volume 14 to a light trap 12a. The light trap 12a minimizes unwanted internal reflections from the beam 22.
A collector or shroud 28 is provided to minimize stray or unwanted reflected light falling upon a sensor 30. The sensor 30 is intended to detect radiant energy from the beam 22 which has been scattered by smoke particulate matter which has entered the smoke chamber 14.
The shroud 28 can be formed as an elongated, cylindrical, tubular member with an open end 28a to provide for entrance of scattered radiant energy. For purposes of improving signal-to-noise ratio, an internal surface 28b (illustrated in phantom) can be provided with a reflective coating or form of a reflective metal so as to increase the level of scattered radiant energy incident upon the sensor 30.
Coupled to the source 20 and the sensor 30 are control circuits 34. The unit 10 can be enclosed within an external housing 36, illustrated in phantom in FIG. 2B, for aesthetic purposes and also to protect it from damage.
Offset from the laser diode 20, is a test light emitting diode 26 which is also carried on the housing 12. The test light emitting diode 26 is energized and provides a beam of radiant energy 26a which is used solely to test the operation of the sensor 30.
The beam of test radiant energy 26a is emitted in a direction which causes it to be more or less directly incident upon the sensor 30. The test light emitting diode 26 is not energized during normal operation of the detector 10.
The electrical circuit block diagram of FIG. 3 illustrates circuitry 34 that assesses a laser diode's performance status via a monitoring signal. An acceptable laser diode status is required to avoid generation of a system "trouble" signal.
During normal operation, a smoke detector integrated circuit 40, such as a Motorola MC145010 or 145011 I.C., periodically signals a laser power supply 42 via a line 44 to energize the laser diode 20. The laser diode 20 contains an integral monitor photodiode 20a which provides feedback information pertaining to laser output radiation on a line 46 to the laser power unit 42.
The laser power supply 42 modifies the quantity of power delivered to the laser diode 20, based upon the feedback information, such that the laser generated radiant energy 22 attains a predetermined power level programmed into the laser power supply 42. The laser diode 20 could be, for example, a Rohm RLD-78 MAT1 laser diode with an integral monitoring circuit.
In the normal mode, and in the absence of smoke, the laser radiation 22 propagates into the radiation trap 12a such that only a very small quantity of stray radiation irradiates the sensor. By "very small quantity" it is meant that the output of the radiation sensor 30 lacks enough magnitude to readily accomplish the described "self test" function, via increased amplifier gain within the smoke detector IC 40.
The smoke detector IC 40 receives radiation sensor signals and information on a line 52 and processes the information, perhaps in conjunction with other system information, to determine and send status and/or fire information output signals on a line(s) 54. More than a single output is possible. Indicating lamps and audible transducers can be energized by one or more of the line(s) 54.
The signals on the line(s) 54 can also be coupled to address and communication circuits 56 where the unit 10 is part of a larger fire alarm system. The circuits 56 can be in bidirectional communication with a communications link 58 of a known type. One form of communications system is disclosed in Tice et al., U.S. Pat. No. 4,916,432 which is assigned to the assignee of the present invention and which is incorporated herein by reference.
In the normal mode and in the presence of smoke, the behavior of the detector 10 resembles the behavior of the detector in the absence of smoke, except that the smoke particles interact with the laser radiation 22 to produce scattered radiation 22a. That scattered radiation irradiates the sensor 30, which in turn generates a signal, on the line 52, indicative of the amount of scattered radiant energy for use by the smoke detector IC 40. The smoke detector IC 40 processes the information, perhaps in conjunction with other system information, to produce a fire indicating output signal and perhaps status or supervisory information on the line(s) 54.
A test signal, generated on a line 62 from test signal circuitry 62a, puts the smoke detector IC 40 into a "test mode". The signal on the line 62 could be generated locally or in response to a command from the remote alarm system control unit. In this instance, the system functions similarly to the normal mode, but some additional activity occurs.
The laser diode monitor status information, from the photodetector 20a, is coupled to supervisory circuitry 64 via the line 46. The supervisory circuitry 64 processes the status information in conjunction with the test signal on the line 62 to produce at least one output on a line 66, which optionally may disable laser power from the supply 42 from reaching the laser diode 20 (illustrated in phantom via line 66a).
The output signal from the supervisory circuitry is processed by a test illuminator circuit 70, in conjunction with the test signal line 62, to produce a corresponding quantity of test radiation 26a. The radiation 26a is produced when the test illuminator circuit 70 energizes the test light emitting diode 26.
The test radiation 26a irradiates the radiation sensor 30, which in turn sends radiation information to the smoke detector IC 40. The smoke detector IC 40 processes the available information, to generate a fire condition indication on the line(s) 54. A suitable output indicates that the detector 10 has satisfactorily passed the test.
The smoke detector IC 40 optionally may employ a high "test mode" gain in the test mode. However, the test illumination circuit 70 provides ample stimulus, via the test beam 26a, for the radiation sensor 30 to produce large magnitude signals for processing by the IC 40 without resorting to use of a higher than "normal mode" gain.
During test mode, if the supervisory circuitry 60 detects an improper status condition for the laser diode 20, then the supervisory circuit 64 can disable the test illuminator circuit 70. In this instance, no radiation irradiates the sensor 30.
The sensor information processed by the IC 40 may be interpreted as indicating unsatisfactory system operation. The smoke detector IC 40 then reports a "trouble" condition, or a zero smoke concentration level on the line(s) 54. This output signal may, in turn, be interpreted as a "trouble" condition detected during a test. A faulty radiation sensor 30 could produce a similar output.
The "trouble" output(s) can be communicated, via communications circuitry 56 and link 58 to the remote fire alarm control unit. Further tests can then be carried out or the detector can be removed and checked.
During the test mode, if the supervisory circuitry 64 detects proper laser diode status, then the supervisory output, line 66, may be chosen to enable the test illuminator circuit 70. If all system components operate properly, then the status and fire information signals, line(s) 54, report the correct predetermined degree of simulated smoke. In this case simulation refers to the test illuminator 70 producing a quantity of radiation 26a to produce a radiation sensor 30 output equal, via line 52, to the radiation sensor output in the presence of a predetermined concentration and type of smoke. Thus, the operation of the laser diode 20 as well as the sensor 30 can be monitored during the test condition.
It will be understood that other monitoring or supervisory functions can be carried out in accordance with the above, without departing from the spirit and scope of the present invention. It will also be understood that some or all of the circuitry 40, 64 could be implemented using one or more interconnected integrated circuits or, alternately, by a programmed microprocessor.
From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is 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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A self-testable photoelectric smoke detector incorporates a housing which defines an internal smoke chamber. The housing carries a laser diode and a radiation sensor along with a supplemental source of test radiant energy. When a test is initiated, the operational characteristics of the laser diode are monitored simultaneously with energizing the source of test radiant energy. Signals from a scattered radiant energy sensor are evaluated via control circuitry, along with signals indicative of performance of the laser diode to determine whether or not the laser diode as well as the radiation sensor are functioning properly.
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FIELD OF INVENTION
This invention relates to novel bonded phase silica products, their use in the separation and purification of proteins, especially proteins having an isoelectric point of below about 5, and the preparation of same. More particularly this invention relates to sulfonic derivatives of N-acylated covalently bound, non-crosslinked polyethyleneimine bonded phase silica products, their use as solid phases suitable for column packing in liquid chromatography for the separation and purification of proteins, especially proteins having an isoelectric point below about 5 and the preparation of same.
BACKGROUND OF THE INVENTION
Alpert and Regnier in J. Chromatogr. 185, 375-392 (1979) have shown that polyethyleneimine (PEI) may be adsorbed to silica surfaces, thereby providing sufficient primary and secondary imino groups on adjacent adsorbed PEI molecules to be crosslinked by multifunctional oxiranes into a polymeric layer. Recently, the separation of synthetic oligonucleotides using high-performance liquid chromatography (HPLC) with columns of microparticulate silica coated with crosslinked polyethyleneimine has been reported in the literature by T. G. Lawson et al., Anal. Biochem. 133, 85-93 (1983).
More recently, new non-crosslinked covalently bound polyethyleneiminopropyl trimethoxy silane silica gel (PEI-PrSi-Silica gel) and polyethyleneiminopropyl trimethoxy silane controlled pore glass (PEI-PrSi-CPG) bonded phase products have been described by Hugh Ramsden in his U.S. Pat. No. 4,540,486, issued Sept. 10, 1985, as being useful in the separation and analysis of protein mixtures.
Since Ramsden's non-crosslinked covalently bound PEI-PrSi-Silica gel and PEI-PrSi-CPG products constitute the substrates to be N-acylated in accordance.with this invention, the disclosure of said U.S. Pat. No. 4,540,486 is incorporated herein in its entirety by reference thereto.
While said PEI-PrSi-Silica gel and PEI-PrSi-CPG bonded phase products have been found to be quite useful as solid phases for column packing in liquid chromatography for the separation and purification of proteins, these bonded phases products have been found not to be sufficiently strong cation exchangers for certain proteins and therefore separation and purification of such proteins has been rendered difficult or impossible. This has been found to be especially the case for separation and purification of proteins having low isoelectric points, that is, below about 5 or so. For example, said bonded phases do not provide sufficiently acceptable separation and purification of proteins such as ovalbumin and bovine serum albumin, for example.
It is, therefore, highly desirable that solid bonded phase products be provided that will permit suitable separation of proteins having isoelectric points of below about 5 and are strong cation exchangers for certain proteins. Additionally, it is highly desirable that there be provided such solid bonded phase products that are substantially fully charged at various pH's of from 2 and above and which provide a greater degree of selectivity than previously permissible. Moreover, it would be advantageous to provide solid bonded phase products that bind proteins more strongly than heretofore and which provide higher capacity by introducing SO 3 - groups adjacent to each COO - location. Furthermore, it would be highly advantageous that solid bonded phase products be provided that bind proteins with isoelectric points less than 5 due to the sulfonic acid group and also bind proteins with isoelectric points greater than 5 due to the combined binding strengths of both the sulfonic acid and carboxylic acid group.
BRIEF DESCRIPTION OF THE INVENTION
It has now been found that the imino and amino functions of the aforementioned non-crosslinked covalently bound PEI-PrSi-Silica gel and PEI-PrSi-CPG bonded phase products of Ramsden's U.S. Pat. No. 4,540,486 may be N-acylated and the N-acylated reaction products further reacted with a water-soluble bisulfite such as potassium or sodium bisulfite or a water-soluble bisulfite precursor to provide sulfonic derivatives of acylated polyethyleneimine bonded phase silica products which are useful as solid phases for the separation and purification of proteins, especially proteins having a low isoelectric point.
The sulfonic derivatives of acylated polyethyleneimine bonded phase silica products of this invention are of the formula ##STR2## is the backbone of a silica gel or controlled pore glass, n is an integer such that the polyethyleneiminopropyl silane group has an average molecular weight of from about 400 to about 1800; q is an integer of zero or one; R is selected from the group consisting of hydrogen, --CH 2 )xH or --CH 2 )mCOOH where x is an integer of 1 or 2 and m is an integer of zero or 1; when R is hydrogen or --CH 2 )xH then R 1 is --CH 2 )pCOOH where p is an integer of zero or 1, and when R is --CH 2 )mCOOH then R 1 is selected from the group consisting of hydrogen or --CH 2 )yH where y is an integer of zero or 1.
DETAILED DESCRIPTION OF THE INVENTION
The sulfonic derivatives of this invention are readily prepared from the non-crosslinked covalently bound PEI-PrSi-Silica gel and PEI-PrSi-CPG bonded phase products of the aforementioned U.S. Pat. No. 4,540,486 by N-acylation thereof with an acylating agent which is an acid of the formula ##STR3## or the acid anhydride or acid halides thereof, wherein q, R and R 1 are as defined in Formula I, to provide N-acylated PEI-PrSi-Silica gel and N-acylated PEI-PrSi-CPG reaction products of the formula ##STR4## wherein n, q, R and R 1 are as defined in Formula I.
The N-acylated reaction products of Formula III are thereafter reacted with water-soluble bisulfite or a water-soluble bisulfite producing reactant (a sodium bisulfite precursor), such as sodium metabisulfite, in the presence of an oxygen source, to introduce a sulfonic radical on the acyl function and thereby provide the novel sulfonic derivatives of Formula I of this invention.
The percent nitrogen in the PEI-PrSi-Silica gel or PEI-PrSi-CPG reactant substrates which is readily determinable by conventional elemental analysis, is indicative of the relative combined total of imino and amino functions on the PEI moiety. Sufficient acylating agent is used to react with substantially all the imino and amino functions on the PEI moiety. In general, the N-acylation step is readily accomplished with an equivalent amount or slight excess of the acylating agent in an inert aprotic organic solvent. Typical aprotic solvents include an aromatic hydrocarbon such as, for example, benzene, toluene, xylene and the like; an ether such as tetrahydrofuran, dioxane and the like, and an aliphatic hydrocarbon such as hexane, heptane and the like. An equivalent amount or slight excess of an acid scavenger such as, for example, a tertiary amine, preferably a tertiary alkyl amine, can be advantageously employed to pick up the acid released during the acylation reaction when acyl halides are used.
Typical acylating agents include acids and the acid anhydrides and acid halides, particularly acid chlorides, of the acids of Formula II such as, for example, maleic, fumaric, mesaconic, citraconic, glutaconic, itaconic acid and the like. Especially preferred as acylating agents are the anhydrides of these acids, particularly maleic anhydride.
Accordingly, this invention first provides a non-crosslinked polyethyleneimine (PEI) function covalently bound to silica gel or controlled pore glass by way of a propylsilyl (PrSi) linkage wherein substantially all, i.e. more than 80% and, preferably, more than 95% of the imino and amino functions of the PEI moiety are acylated with an acyl function, which acyl functions are then reacted with a bisulfite producing reactant to provide the novel sulfonic derivatives of this invention.
Reaction of N-acylated PEI-PrSi-Silica gel and N-acylated PEI-PrSi-CPG reaction products with bisulfite or a bisulfite precursor is conducted in the presence of an oxygen source such as oxygen, air, potassium persulfate, benzoyl peroxide and the like.
The silica gel and controlled pore glass forming the backbone of the solid phase bonded silica products of this invention is silica gel having an average particle diameter of from about 3 to about 70 microns and an average pore size of from about 50 to about 1000 Angstrom units, or particulate controlled pore glass having an average particle diameter of from about 37 to about 177 microns and an average pore size of from about 40 to about 1000 Angstrom units, with polyethyleneiminopropyl trimethoxy silane having an average molecular weight of from about 400 to about 1800.
The sulfonic derivatives of N-acylated PEI-PrSi-Silica gel or PEI-PrSi-CPG bonded phase products of Formula I constitute new and useful bonded phases for the purification and separation of proteins by column chromatography and are particularly suitable with modern HPLC instrumentation. The packing may be of various mesh sizes, for example, from about 50 to about 600 mesh.
The preferred sulfonic derivatives of N-acylated PEI-PrSi-Silica gel bonded phase products of Formula I are those obtained from the reaction product of particulate silica gel having an average particle diameter from about 5 to about 40 microns and an average pore size of from about 50 to about 330 Angstrom units and polyethyleneiminopropyl trimethoxy silane having an average molecular weight of from about 400 to about 600; and those obtained from particulate silica gel having an average particle diameter of from about 40 to about 62 microns and an average pore size of from about 250 to about 500 Angstrom units and polyethyleneiminopropyl trimethoxy silane having an average molecular weight of about 1000.
It is believed that the subject sulfonic derivative of N-acylated PEI-PrSi-Silica gel and PEI-PrSi-CPG bonded phase products of Formula I separate proteins on the basis of both weak and strong ionic interaction. The marked advantages in separating proteins with the subject products are deemed surprising and unusual since presently available chromatographic matrixes that separate on this basis generally give broad peaks with poor selectivity, have poor stability, low capacity and give non-quantitative recovery of proteins. In contrast, the chromatographic matrixes of this invention provide sharp well-defined peaks with good selectivity are highly stable, have high capacity and exhibit quantitative recovery of both protein mass and, in the case of enzyme separation, without significant loss of enzyme activity.
Moreover, with the novel bonded phase products of this invention changes in buffer composition and changes in buffer pH allows for changes in the relative elution profiles of various protein mixtures.
The present invention is even more surprising since one would normally expect the herein described chromatographic matrixes to be hydrolytically unstable in aqueous high ionic strength mobile phases used for hydrophobic interaction chromatography due to the inherent solubility characteristics of silica in such high ionic strength aqueous solutions. Thus, one would normally expect that the use of silica bases matrixes would necessarily result in short column lifetimes. The opposite, however, is true with the subject sulfonic derivatives of N-acylated PEI-PrSi-Silica gel and PEI-PrSi-CPG bonded phase products of Formula I.
Additionally, the sulfonic derivatives of the N-acylated PEI-PrSi-Silica gel and PEI-PrSi-CPG bonded phase products of Formula I have the advantage of offering a greater degree of selectivity in protein separation and purification, binding proteins more strongly and offering higher capacity for columns in which they are used as packings. Moreover, these products of Formula I are substantially fully charged at pH's of from about 2 and above and are sufficiently strong cation exchangers that they can be readily used to separate and purify proteins having low isoelectric points, that is of below about 5 or so, particularly proteins such as ovalbumin and bovine serum albumin and the like.
Another advantage offered by the bonded phase products of Formula I is that such bonded phases readily permit change of pH of the buffer system employed in the protein separation and purification steps.
The N-acylated PEI-PrSi-Silica gel and N-acylated PEI-PrSi-CPG reaction products of Formula III also are new bonded phase products which find utility as intermediates for the preparation of the sulfonic derivatives of Formula I.
In the following examples PEI-PrSi-Silica gel and PEI-PrSi-CPG, prepared as in the following Preparations, are employed as the starting reactants and it will be appreciated that said reactant is merely exemplary and that other PEI-PrSi-Silica gels or PEI-PrSi-CPG bonded phases, in accordance with the foregoing description and the disclosure in the aforementioned U.S. Pat. 4,540,486, could be employed in accordance with the following examples to provide other sulfonic derivatives of Formula I of this invention.
PREPARATION A
PEI-PrSi-Silica Gel
To 100 grams silica gel with an average particle diameter of 40 microns and an average pore size of 250 Angstroms, 500 ml propanol and 49.5 grams (47.1 ml) polyethyleneiminopropyl trimethoxysilane having an average molecular weight of about 500 is added with stirring and the mixture allowed to stand at room temperature for about 48 hours. The reaction mixture is next vacuum filtered and the filtrate washed twice with 400 ml portions of 2-propanol and twice with 400 ml portions of methanol and then oven dried at about 80° C. for about four hours. The product was reslurried in 500 ml deionized water and again filtered and washed with methanol several times and then oven dried for a second time at about 80° C. for about 4 hours to yield about 95.5 grams of covalently bound PEI-PrSi-Silica gel product. Analysis: 5.08% C, 1.43% H and 2.22% N.
PREPARATION B
PEI-PrSi-Silica Gel
To 100 grams silica gel having an average particle diameter of about 5.25 microns and an average pore size of about 330 Angstroms is added 500 ml toluene, 2 ml water and 50 ml of a 50% w/w isopropanolic solution polyethyleneiminopropyl trimethoxy silane having as average molecular weight of about 500 and the mixture stirred and permitted to stand at room temperature for about 48 hours. The mixture is then filtered and the filtrate washed twice with 500 ml portions of toluene and twice with 500 ml portions of methanol and then dried in an oven at about 80° C. for about 2 hrs. 45 minutes. The product was reslurried in water, filtered, washed with water and methanol and oven dried again at about 80° C. for about 11/2 hour. Yield: 93.0 grams. Analysis: 3.31% C, 1.30% H and 1.25% N.
PREPARATION C
PEI-PrSi-CPG
To a slurry of 10 grams controlled pore glass with average particle diameter of 125 microns and average pore size of 240 Angstroms in 50 ml hexane is added 19.71 grams of a 50% w/w isopropanolic solution of polyethyleneiminopropyl trimethoxy silane having an average molecular weight of 500. The mixture is stirred for 5 minutes at room temperature and then heated to reflux temperature for about 2 hours. The mixture is allowed to cool to room temperature, filtered and washed with 50 ml hexane twice and 50 ml methanol twice. The filtrate is then oven dried at about 80° C. for about 3 hours to yield the covalently bonded, non-crosslinked PEI-PrSi-CPG product.
The following examples are presented to illustrate and exemplify this invention
EXAMPLE 1
To 50 grams of PEI-PrSi-Silica gel product of Preparation A in 250 mls toluene is added 20 grams maleic anhydride with stirring. The reaction mixture is heated at about 65° C. for 41/2 hours. The reaction product is filtered, washed thrice with methanol and then oven dried at about 80° C. for about 11/2 hours. Yield: 57.7 grams; Analysis: 8.78% C, 1.47% H, 2.13% N, titre: 0.65 meq/gram. Twenty grams of this reaction product and 13 ml of lN NaOH are then mixed with 9.5 grams sodium metabisulfite in 100 ml H 2 O and mixed thoroughly. The reaction mixture is placed in a hot bath at about 80° C., open to the air, for a period of about 6 hours. The reaction product is filtered, washed successively twice with water and twice with methanol and placed in an oven at about 80° C. for a period of about 31/2 hours to dry. Yield: 20.62 grams; Analysis: 7.26% C, 1.56% H, 1.94% N, 2.03% S; 0.634 meq/g sulfonic acid.
EXAMPLE 2
The procedure of Example 1 is repeated except that 50 grams of the PEI-PrSi-Silica gel product of Preparation B is substituted for the PEI-PrSi-Silica gel product of Preparation A to yield the corresponding sulfonic bonded phase N-acetylated PEI-PrSi-Silica gel derivative.
EXAMPLE 3
The procedure of Example 1 is repeated except that an equivalent quantity of the PEI-PrSi-CPG product of Preparation C is substituted for the PEI-PrSi-Silica gel product o Preparation A to yield the corresponding sulfonic derivative of N-acylated PEI-PrSi-CPG bonded phase.
EXAMPLE 4
The procedure of Example 1 is repeated except that an equivalent quantity of citraconic acid anhydride is substituted for the maleic acid anhydride to yield the corresponding sulfonic derivative of N-acylated PEI-PrSi-Silica gel bonded phase.
EXAMPLE 5
The procedure of Example 1 is repeated except that an equivalent quantity of glutaconic acid anhydride is substituted for the maleic acid anhydride to yield the corresponding sulfonic derivative of N-acylated PEI-PrSi-Silica gel bonded phase.
EXAMPLE 6
The procedure of Example 1 is repeated except that an equivalent quantity of itaconic acid anhydride is substituted for the maleic acid anhydride to yield the corresponding sulfonic derivative of N-acylated PEI-PrSi-Silica gel bonded phase.
EXAMPLE 7
A standard analytical column (4.6 mm internal diameter ×250 mm length) is slurry packed at high pressure (7500 psi) with sulfonic derivative of PEI-PrSi-Silica gel (about 40 microns; about 250 Angstroms) obtained from Example 1 as the bonded phase. The slurry consists of 3.0 grams of the sulfonic derivative of PEI-PrSi-Silica gel in 25 mls methanol. After pumping the slurry into the column, an additional 100 mls methanol are then pumped through the column at the same pressure. The column is attached to a high pressure liquid chromatograph and a solution of 500 millimolar NaOAC, pH 7, is pumped through the column at 1 ml/min. at 1200 psi flow rate until a steady baseline is observed at 280 nm. A solution of 25 millimolar KH 2 PO 4 , pH 6, is then pumped at about the same flow rate through the column until a steady baseline is achieved. A solution (100 microliters) of a protein mixture dissolved in the low salt buffer A, made up of 25 mM KH 2 PO 4 , is injected into the column and the protein components are eluted by increasing the salt concentration to 500 mM NaOAC (buffer B) over 30 minutes at 1 ml/min. The mixture of proteins included 500 micrograms of cytochrome C; 500 micrograms of hemoglobin; 500 micrograms of lysozyme and 500 micrograms of ovalbumin. Each protein elutes as a concentrated band, well separated from each other. Typical mass recoveries for the individual proteins were greater than ninety percent of the original amount, for example, 97% of cytochrome C, 96% of hemoglobin, 95% of lysozyme and 95% of ovalbumin. The column of this example does not demonstrate any significant loss in chromatographic performance even after 1000 hours of chromatographic use for protein separation.
EXAMPLE 8
A standard analytical column (4.6 mm internal diameter ×250 mm length) is slurry packed at high pressure (7500 psi) with sulfonic derivative of PEI-PrSi-Silica gel (about 40 microns; about 300 Angstroms) obtained from Example 1 as the bonded phase. The slurry consists of 3.0 grams of the sulfonic derivative of PEI-PrSi-Silica gel in 25 mls methanol. After pumping the slurry into the column, an additional 100 mls methanol are then pumped through the column at the same pressure. The column is attached to a high pressure liquid chromatograph and a solution of 500 millimolar NaOAC, pH 7, is pumped through the column at 1 ml/min. at 1200 psi flow rate until a steady baseline is observed at 280 nm. A solution of 25 millimolar KH 2 PO 4 , pH 6, is then pumped at about the same flow rate through the column until a steady baseline is achieved. A solution (100 microliters) of a hybridona cell culture media diluted 4 fold in the low salt buffer A, made up of 25 mM KH 2 PO 4 , is injected into the column and the protein components are eluted by increasing the salt concentration to 500 mM NaOAC (buffer B) over 60 minutes at 1 ml/min. The antibody is eluted at >80% purity later in the gradient than any other protein constituent.
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Sulfonic derivatives of N-acylated covalently bound, non-crosslinked polyethyleneimine bonded phase silicas of the formula: ##STR1## is the backbone of a silica gel or controlled pore glass, n is an integer such that the polyethyleneiminopropyl silane group has an average molecular weight of from about 400 to about 1800; q is an integer of zero or one; R is selected from the group consisting of hydrogen, --(CH 2 ) x H or --(CH 2 ) m COOH where x is an integer of 1 or 2 and m is an integer of zero or 1; when R is hydrogen or --(CH 2 ) x H then R 1 is --(CH 2 ) p COOH where p is an integer of zero or 1, and when R is --(CH 2 ) m COOH then R 1 is selected from the group consisting of hydrogen or --(CH 2 ) y H where y is an integer of zero or 1, are especially useful as solid phases for the purification and separation of proteins having isoelectric points of below about 5.
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STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0001] This invention was made with Government support under contract #F33615-03-M-2316 awarded by the Air Force Research Laboratory. The Government has certain rights in this invention.
CROSS REFERENCE TO RELATED APPLICATIONS
[0002] None
BACKGROUND
[0003] 1. Field of the Invention
[0004] The present invention relates generally to spray cooling thermal management systems and more specifically it relates to a spray cooling system that provides high heat flux evaporative cooling of electronic component hotspots.
[0005] 2. Description of the Related Art
[0006] Liquid cooling is well known in the art of cooling electronics. As air cooling heat sinks continue to be pushed to new performance levels, so has their cost, complexity, and weight. For some time, liquid cooling solutions have been developed and tested, but other than specialty applications they have yet to gain widespread commercial adoption. As computer power consumptions continue to increase, liquid cooling will provide significant advantages to computer manufacturers which will force its use. The present invention provides significant advantages over both air cooling and prior art liquid cooling solutions.
[0007] Liquid cooling technologies use a cooling fluid for removing heat from an electronic component. Liquids can hold and transfer heat at a rate many times that of air. Single-phase liquid cooling systems place a pure liquid in thermal contact with the component to be cooled. With these systems, the cooling fluid absorbs heat as sensible energy. Other liquid cooling systems, such as spray cooling, are two-phase processes. In these systems, heat is absorbed by the cooling fluid as latent energy gains. Two-phase cooling, or commonly referred to as evaporative cooling, provides the ability to deliver more efficient, more compact and higher performing liquid cooling systems than single-phase systems.
[0008] An exemplary two-phase cooling method is spray cooling. Spray cooling uses a pump for supplying fluid to one or more nozzles that transform the coolant supply into droplets. These droplets impinge the surface of the component to be cooled and can create a thin coolant film. Energy is transferred from the surface of the component to the thin-film. Because the fluid is dispensed at or near its saturation point, the absorbed heat causes the thin-film to turn to vapor. This vapor is then condensed, often by means of a heat exchanger, or condenser, and returned to the pump.
[0009] Significant efforts have been expended in the development and optimization of spray cooling. A doctorial dissertation to Tilton entitled “Spray Cooling” (1989), available through the University of Kentucky library system, describes how optimization of spray cooling system parameters, such as droplet size, distribution, and momentum can create a thin coolant film capable of absorbing high heat fluxes. As described by the Tilton dissertation, atomization plays a key role in the development of a thin coolant film capable of absorbing very high heat fluxes, such as a coolant film capable of absorbing a heat flux over 800 watts per square centimeter. Research and development by Isothermal Systems Research (ISR) has shown spray cooling to be capable of absorbing heat fluxes in the range of several thousands watts per square centimeter.
[0010] In addition to the system parameters described by the Tilton dissertation, U.S. Pat. No. 5,220,804 provides a method of increasing a spray cooling system's ability to remove heat. The '804 patent describes a method of managing system vapor that further thins the coolant film which increases evaporation, improves convective heat transfer, and liquid and vapor reclaim.
[0011] Historically, most electronic cooling solutions have provided wide area treatment of the cooling surface. Electronic components are rated to a total wattage that is spread by an aluminum, copper, or diamond heat spreader to the cooling fluid (may be air or liquid). In some applications, this wide-area average heat flux treatment of the cooling surface only marginally takes advantage of the benefits of liquid cooling over air cooling.
[0012] Electronic components create varying amounts of heat across their surfaces and a varying amount of heat as a function of time. Today's microprocessors, for example, may be constructed on a silicon die roughly 1 cm by 1 cm. The die may have multiple zones for different functions. Such zones may be for inputs and outputs (I/Os), level 1 cache, level 2 cache, and the core. The core may be roughly 0.5 cm by 0.5 cm and is where the main computer processing takes place. Although the core may only be 25% of the total area of the die, it creates almost the entire heat generation by the chip and may be considered a chip “hotspot”. Wherein a chip might be rated for an average heat load of 110 watts, with an average heat flux of 110 watts per centimeter squared, the core may generate 100 watts of that heat and have a heat flux of 400 wafts per centimeter squared. This non-uniform heat flux distribution poses a significant challenge to the cooling system as it is desirable to keep the entire chip at nearly the same operating temperature. Cooling systems that rely on heat spreading may not provide this ability as they rely on conduction spreading, resulting in significant temperature gradients across the chip.
[0013] One method of cooling the core of a computer chip is to divide the chip into thermal zones and to cool each of the chip's zones at a different rate. U.S. Pat. No. 6,443,323, describes a method of variably cooling a computer component through the use of incremental sprayers. The incremental sprayers deposit fluid onto each zone at a mass flow rate necessary for complete phase change. Drops are ejected from an orifice in serial. Although this method improves the efficiency of the system, that is in attaining complete phase change of all dispensed fluid, the incremental dispensing method does not provide dispensing characteristics necessary to create high heat flux thin-film evaporative cooling and high performance cooling of hotspots. A paper by Don Tilton and Jay Ambrose (1989), entitled “Closed-System, High-Flux Evaporative Spray Cooling”, describes the early development and analysis of incremental sprayers and predicts a maximum heat flux capability of around 300 watts per centimeter squared using water. An ASME paper published by Bash, Patel, and Sharma entitled “Inkjet Assisted Spray Cooling of Electronics” (2003), describes an inkjet dispensing system with a critical heat flux of around 270 watts per centimeter squared using water.
[0014] Another method of cooling the core is described by U.S. Pat. No. 6,650,542. Although this method directs and controls the single phase fluid over a chip hotspot, the disclosed method is not a phase change process and thus not capable of high heat flux thin-film evaporative cooling.
[0015] Yet another method of cooling the core is two-phase microchannels, such as described by U.S. Pat. No. 4,450,472. Although this method does not use spray cooling, the design does provide the ability to remove heat in the range of 400-1000 watts per square centimeter using water. The system discloses a method of placing a very small microchannel array on an electronic component. Although microchannel cooling methods may effectively lower the temperature of the core, due to large pressure drops and resulting size limitations they do not efficiently address the needs of the non-hotspot areas of the die.
[0016] For the foregoing reasons, there is a need for a liquid cooling solution that effectively cools the one or more hotspots of a computing component. Thus, there is a need for a localized cooling solution capable of absorbing large heat fluxes. Also, the high heat flux cooling system must efficiently and reliably cool the other non-high heat flux areas of the chip. The resulting cooling solution would allow significant improvements in processor performance.
BRIEF SUMMARY OF THE INVENTION
[0017] In order to solve the problems of the prior art, and to provide a spray cooling solution that significantly changes the thermal constraints of the core, a hotspot spray cooling solution has been developed.
[0018] The present invention is a spray cooling thermal management device that cools an electronic component creating a varying amount of heat across its surfaces. Liquid coolant is dispensed upon the surface of the component. In areas of the chip that generate large heat fluxes, typically referred to as the core, the liquid coolant is dispensed as a continuous atomized droplet pattern. The atomized pattern creates a high heat flux evaporative cooling thin-film over the one or more core areas. Rather than optimize the atomized pattern and flow based upon complete thin-film vaporization, the present invention optimizes the atomized pattern for maximum heat removal rates. Any excess, non-vaporized, fluid flowing outward from the hotspot is used to cool the lower heat flux (non-core) areas of the component through the creation of a thick coolant film thereon.
[0019] Other embodiments of the invention include supplemental nozzles that deposit cooling fluid into the thick-film. This embodiment provides an efficient and simple method of controlling the cooling rates over the less critical system zones and provides further flexibility in optimizing the atomization for the high heat flux areas.
[0020] Another embodiment of the present invention utilizes an atomizer that dispenses the coolant at a non-perpendicular angle to one or more component hotspots. This embodiment provides directional control of the excess fluid of the hot spot. The thick-film is encouraged to flow in a predetermined direction.
[0021] Another embodiment of the present invention uses a liquid-vapor separator for separating liquid and vapor from the exit stream of a spray module prior to condensing the vapor. The result is a near pure vapor at the inlet of the condenser which is potentially more efficient and has a more repeatable performance than a condenser with substantial two-phase flow at its inlet.
[0022] Yet another embodiment of the present invention enhances the surface of the chip to be spray cooled through the use of etched open microchannels. These microchannels are formed either directly into the top surface of the chip or through the use of a secondary etched microchannel plate bonded to the top surface of the chip.
[0023] These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] In the course of the detailed description to follow, reference will be made to the attached drawings. These drawings show different aspects of the present invention and, where appropriate, reference numerals illustrating like structures, components, and/or elements in different figures are labeled similarly. It is understood that various combinations of the structures, components, and/or elements other than those specifically shown are contemplated and within the scope of the present invention:
[0025] FIG. 1 is a perspective view of a computer chip mounted onto a substrate;
[0026] FIG. 2 is a top view of computer chip with multiple zones;
[0027] FIG. 3 is a perspective view of a spray module mounted onto the substrate and encompassing the chip from FIG. 1 ;
[0028] FIG. 4 is a section view, along line A-A of FIG. 3 , showing the inside the a spray module according to the present invention;
[0029] FIG. 5 is a partial view of FIG. 4 showing a spray plate located over the chip to be cooled according to the present invention;
[0030] FIG. 6 is a side view of a spray plate with hotspot vapor management protrusions;
[0031] FIG. 7 is an alternative embodiment of the present invention showing a secondary nozzle spraying onto the thick-film;
[0032] FIG. 8 is another alternative embodiment of the present invention showing an angled atomizer;
[0033] FIG. 9 is a bottom perspective view of a spray plate with a hotspot vapor management protrusion;
[0034] FIG. 10 is a block diagram of a simple spray cool system;
[0035] FIG. 11 is a block diagram of a spray cool system using a liquid and vapor separator;
[0036] FIG. 12 is a side section view of a separator of FIG. 11 ; and
[0037] FIG. 13 is a side partial view of a spray cooled secondary etched microchannel plate, with the microchannels enlarged for clarity.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0038] Many of the fastening, connection, manufacturing and other means and components utilized in this invention are widely known and used in the field of the invention are described, and their exact nature or type is not necessary for a person of ordinary skill in the art or science to understand the invention; therefore they will not be discussed in detail.
[0039] Applicant hereby incorporates by reference the following U.S. patents: U.S. Pat. No. 5,220,804 for a high heat flux evaporative cooling system; and U.S. Pat. No. 5,860,602 and U.S. Pat. No. 6,016,969, each for a laminated array of pressure swirl atomizers, and U.S. Pat. No. 6,108,201 for a fluid control apparatus and method for spray cooling and U.S. patent application Ser. No. 10/281,391 for an actuated atomizer. Although a laminated pressure swirl atomizer array is hereby incorporated by reference and shown in the accompanying drawings, the present invention is not limited to such an apparatus, in fact, many dispensing means are applicable to the present invention, including but not limited to, inserted atomizers, jet orifices, and actuated atomizers. Applicant herein incorporates by reference co-pending U.S. patent application entitled “Hotspot Coldplate Spray Cooling System”, also filed on Feb. 24, 2004. This application is related to co-pending U.S. patent application entitled “Etched Open Microchannel Spray Cooling”, also filed on Feb. 24, 2004.
[0040] Now referring to FIG. 1 , a computer chip 2 is shown mounted to a substrate 4 , as typical in computing applications. Computer chip 2 may be a microprocessor, Field Programmable Gate Array (FPGA), Application Specific Integrated Circuit (ASIC), or any other commonly used electronic component. Chip 2 is attached to substrate 4 using any one of a wide range of commonly known packaging technologies (not shown), including: ball grid array, pin grid array, land grid array, and wirebond. The present invention is not limited to any one particular interconnect or packaging method.
[0041] FIG. 2 shows a typical microprocessor version of chip 2 . The top surface of chip 2 has several zones, each with a unique function, unique power consumption, and thus, a unique heat generation rate. Although multiple zones are identified by FIG. 2 , they can be lumped into high and low heat flux zones. Low heat generation zones may be, but are not limited to, memory (L1 and L2 cache), I/Os and controllers. A core 3 , where significant computations take place, generates heat at a much greater rate than the low heat generation zones. A chip may have multiple hotspots as areas of execution and floating point calculations may be done in separate locations on the die, each hotspot located over a core.
[0042] FIG. 3 , and according to the present invention, shows a spray module 10 attached to substrate 4 and encompassing chip 2 . Spray module 10 may be attached to substrate 4 through the use of adhesives, soldering, or mechanical fastening such as but not limited to the methods described by U.S. Pat. No. 6,108,201 incorporated herein by this reference. Spray module 10 is used for dispensing a supply of liquid coolant onto the surface of chip 2 . Fluid enters module 10 through an inlet 14 and exits through an outlet 16 . Although only one outlet 16 is shown, multiple are possible. In fact, wherein computer desktops are most often orientated in one of two orientations, desktop or tower, it may be preferable to have a plurality of outlet 16 at ninety degree angles to each other.
[0043] Spray module 10 is part of a well known and understood two-phase cooling cycle (shown in FIG. 10 ). A pump 5 is used for supplying a cooling fluid at an optimal spray cooling flow rate and pressure level. The cooling fluid can be any one of the well known spray cooling fluids, including but not limited to FC-72, Fluorinert (a Trademark of 3M), water and water mixtures. From pump 5 , the high pressure cooling fluid enters spray module 10 where it absorbs heat from chip 2 . A condenser 8 cools the fluid and returns liquid to pump 5 . The system and components of the spray cool system are well known and understood in the field, and thus, they will not be discussed in further detail.
[0044] Spray module 10 , according to the present invention, has an outer housing 12 that provides the structural rigidity to the overall module. Housing 12 can be constructed from many materials, including aluminum and plastic. Ideally, housing 12 is designed to provide the ability to be molded or die-casted (as shown in FIG. 4 ), thus providing low manufacturing costs.
[0045] Also shown in FIG. 4 , a fluid supply enters inlet 14 located at the top of housing 12 , by means of a supply tube (not shown). The connection between inlet 14 and the supply tube is preferably removable through the use of a common quick disconnect fitting. The coolant flowing through inlet 14 then enters a manifold area created between housing 12 and a spray plate 30 .
[0046] Spray plate 30 provides the means for dispensing the cooling fluid onto chip 2 . Plate 30 is shown inserted into a pocket within housing 12 , where it can be glued, fastened or swaged into place. Due to the one piece design of housing 12 , it is not necessary to provide a fluid tight seal between spray plate 30 and housing 12 , but it is desirable to provide a tight fit and thus minimize pressure losses. Spray plate 30 contains one or more nozzles that provide the means of transforming the supply of coolant into one or more continuous droplet streams. In FIG. 4 , an atomizer 32 is shown located over core 3 . Although one atomizer 32 is shown, depending upon the type of fluid used, the size of core 3 , and the spray cone angle of atomizer 32 , there may be one or more atomizers placed above core 3 . To minimize mixing between adjacent atomizers, it is preferable to use a single atomizer per hotspot. A method of creating spray plate 30 is described by U.S. Pat. No. 5,860,602 and U.S. Pat. No. 6,016,969 for a laminated pressure swirl atomizer. Another method is to insert button-style atomizers into plate 30 . In the event that chip 2 produces highly variable heat fluxes as a function of time, that is it cycles from peak performance to “sleep” mode, it may be advantageous to make atomizer 32 variable and controllable as described by U.S. patent application Ser. No. 10/281,391. The variable atomizer in conjunction with an electronic control system makes it possible to achieve direct component temperature feedback and overall thermal performance control.
[0047] As previously mentioned, it is highly desirable to remove heat directly from core 3 prior to it spreading to the rest of chip 2 . Atomizer 32 provides the means for removing significant amounts of heat directly from core 3 . Through the use of atomizer 32 , droplet size, distribution and momentum can all be controlled and optimized in a fashion that provides a thin-film 40 over core 3 , as shown in FIG. 5 . As described by the dissertation by Tilton, the thickness of thin-film 40 can significantly affect the ability of the coolant to remove heat. Generally, the thinner thin-film 40 becomes the more heat it can remove.
[0048] Creation and optimization of thin-film 40 is application specific. If impinging droplets impact film 40 with too little momentum, the droplets will be entrained into the escaping vapor and they will not reach the cooling surface. If the impinging droplets have too much momentum, the droplets will splash from the surface and not contribute to cooling. Both conditions can not be completely avoided but should be minimized. In addition to the above optimization, ideally, impinging droplets will collide with thin-film 40 in a fashion that destroys nucleating bubbles. Nucleating bubbles aid in the desired vaporization of liquid coolant, but reduce the contact area between the higher conductive liquid and the lower conductive vapor. Ideally, nucleating bubbles are destroyed before they can achieve significant size.
[0049] Optimization of coolant dispensing characteristics may also yield a unique event that occurs when droplets impinge a flat surface, called hydraulic jump. This jump process occurs when a thin-film fluid flows radially and then jumps in height based upon its Froude number going from supercritical (thin-film) to subcritical (thick-film). As documented by the Tilton dissertation, a supercritical thin-film may be, but is not limited to, the range of 100 micrometer to 400 micrometers thick, and the jumped thick-film may be in the range, but is not limited to, 3000 micrometers to 4000 micrometers using water. A hydraulic jump provides the means of creating thin-film 40 and thick-film 42 and the ability to cool core 3 of chip 2 at a rate greater than the non-core areas of chip 2 . A hydraulic jump may also provide a thermal buffer in the event that spray becomes momentarily interrupted.
[0050] As shown in FIG. 5 , and in the fashion described above, atomizer 32 is located generally over core 3 so that thin-film 40 is also created directly over core 3 . Rather than attempt to extend thin-film 40 over the entire surface of chip 2 , as is attempted by the prior art, the present invention optimizes its spray characteristics over just core 3 . This is likely to result in a jumped thick-film 42 over the non-core areas of chip 2 . Wherein thin-film 40 may be capable of absorbing heat fluxes up to a thousand or more watts per square centimeter over the small area of core 3 , thick-film 42 may be capable of efficiently and reliably providing heat removal rates generally less than 100 watts per square centimeter over the large area low-heat-flux zones of chip 2 .
[0051] Heat removal rates of both zones, 40 and 42 , may be improved the use of surface enhancements. One such enhancement is etched microchannels on the top surface of chip 2 . The process of etching microchannels is described by U.S. Pat. No. 4,450,472 and U.S. patent application Ser. No. 10/052,859, both are herein incorporated by reference. Although these methods are disclosed as part of closed channel microchannel cooling systems, open etched microchannels may significantly increase the effectiveness of the present spray cooling invention. Open channel spray cooled microchannels are not limited by pressure drops created by the need for small hydraulic diameters, as is the case with closed microchannel systems. Open microchannel spray cooling is also limited by the need to use fluid manifolding. Therefore, open microchannel spray cooling may provide the ability to have smaller hydraulic diameters, and higher resulting heat transfer coefficients, than closed microchannel cooling systems. As an alternative surface enhancement embodiment and as shown in FIG. 13 , a secondary etched microchannel plate 44 may be thermally attached to chip 2 providing the benefits of surface enhancements and the potential use of a non-dielectric fluid. Both open channel spray cooling microchannel methods provide increased nucleation sites, improved vaporization conditions and increased surface areas; all of which are known to benefit spray cooling.
[0052] As an alternative embodiment of the present invention and shown in FIGS. 4 and 6 , a hotspot vapor management protrusion 34 extends from spray plate 30 in the direction of and in a spaced apart relationship to chip 2 . As described by U.S. Pat. No. 5,220,804 and U.S. Pat. No. 6,108,201, vapor management protrusion 34 forces the vapor within the system, and more particularly vapor in close proximity to the atomization zone, to flow downward and outward along thin-film 40 . The result is a further thinning of thin-film 40 and increased heat removal rates. The gap between chip 2 and vapor management protrusion 34 is a variable of design, often optimized through experimentation, but ISR typically uses gaps between ½ mm and ¾ mm. In the event that multiple hotspots are present on a given chip, it may be desirable to have multiples of atomizer 32 and multiples of vapor management protrusion 34 . Also located in protrusion 34 , and shown in FIG. 9 , is a plurality of vapor return orifices 37 which allow for the recirculation of vapor within spray module 10 .
[0053] In addition to cooling chip 2 by the above described fluid dispensing process, FIG. 7 shows a secondary nozzle 36 used to assist in the creation and performance of thick-film 42 . In areas of moderate heat fluxes, such as critical memory areas, it may be desirable to increase the cooling in those areas by creating localized thinner zones within thick-film 42 . In addition, nozzle 36 may simply add fluid to thick-film 42 in the event that atomizer 32 does not produce enough excess fluid to maintain thick-film 42 over the low heat flux areas of chip 2 . Unlike the requirements placed on atomizer 32 , nozzle 36 is not required to produce a thin evaporative film capable of very large heat fluxes. In this case, nozzle 36 may be, but is not limited to, an incremental sprayer, a drop on demand orifice, a jet orifice, a piezoelectric actuated jet impingement orifice, or an actuated atomizer. All methods provide the means of supplementing the cooling fluid to thick-film 42 .
[0054] FIG. 8 shows another alternative embodiment of the present invention. In this embodiment, atomizer 32 dispenses fluid at a generally non-perpendicular angle to core 3 . By spraying at a non-perpendicular angle to core 3 , thick-film 42 is further encouraged to flow over and cover the non-hotspot areas of chip 2 . This embodiment may also achieve benefits through they the addition of secondary nozzle 36 or vapor management protrusion 34 . Angled spray cooling may also benefit from the addition of etched microchannels parallel to the direction of spray.
[0055] Cooling fluid that exits spray module 10 is not likely to be a pure vapor, as ideal in terms of cycle efficiency. Although prior art systems try to optimize the spray system for complete fluid vaporization within module 10 , the present invention is optimized for cooling the performance enhancing core of a chip. Although the higher performance of the present invention is at the cost of complicated two phase flow within condenser 8 , FIG. 12 shows an addition to the system that simplifies its design and use. A separator 7 may be placed between condenser 8 and spray module 10 . Separator 7 separates liquid from vapor and transfers the higher energy vapor to condenser 8 and the lower energy liquid to pump 5 ( FIG. 13 ). In addition, vapor and liquid may be separated through the use of a spiral separator as described by U.S. Pat. No. 5,314,529. Liquid—vapor separation allows the size of condenser 8 to be minimized.
[0056] While the hot spot cooling system herein described constitute preferred embodiments of the invention, it is to be understood that the invention is not limited to these precise form of assemblies, and that changes may be made therein with out departing from the scope and spirit of the invention.
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The present invention is a spray cooling thermal management device that cools an electronic component creating a varying amount of heat across its surfaces. Liquid coolant is dispensed upon the surface of the component. In areas of the chip that generate large heat fluxes, typically referred to as the core, the liquid coolant is dispensed as a continuous atomized droplet pattern. The atomized pattern creates a high heat flux evaporative cooling thin-film over the one or more core areas. Rather than optimize the atomized pattern and flow based upon complete thin-film vaporization, the present invention optimizes the atomized pattern for maximum heat removal rates. Any excess, non-vaporized, fluid flowing outward from the hotspot is used to cool the lower heat flux (non-core) areas of the component through the creation of a thick coolant film thereon.
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FIELD OF THE INVENTION
The present invention pertains to an arrangement in a liquid fuel-operated heater for vehicles, which heater is operated independently of the engine of the vehicle, with a combustion chamber, whose wall has air passage openings with a downstream flame tube, a heat exchanger and means for supplying fuel and for supplying combustion air, and an igniting device, as well as means for removing the heating air and for discharging flue gas, as well as an annular space surrounding the combustion chamber.
BACKGROUND OF THE INVENTION
Such heaters have been known as auxiliary heaters for heating passenger compartments of vehicles, boats or construction equipment while the engine of the vehicle is not in operation, and have been commercially available for many years. These prior-art heaters are designed for a defined rated capacity, so that sufficient heating with the vehicle engine not running or additional heating with the engine running and consequently supplying heat is possible even under extreme conditions. If only a small amount of heat is to be supplied, this is achieved in the prior-art heaters either by intermittent operation or by operation at partial load, usually at 1/4 load at the lowest level.
It has been known that the burners of such heaters are operated, regardless of the mode of fuel supply and the mixture preparation, with an air ratio of lambda λ=1.2-1.5 at full load. To operate the burner in the partial load range, the amount of fuel must be reduced corresponding to the changed output ratio (partial load:full load). To achieve satisfactorily clean combustion, the amount of combustion air must be adjusted as well. Investigations carried out in this connection have shown that air ratios of lambda λ=2 lead to the relatively best combustion values at the 1/4 partial load that is commonly used currently. However, this depends essentially on the design of the burner. Thus, air ratios in the range of lambda λ=3-4 are obtained for some prior-art combustion chambers. These high air ratios are necessary in order to achieve still satisfactorily clean combustion with still tolerable emission values in the partial load range. The necessary reduction of the amount of combustion air is brought about in the prior-art heaters corresponding to the partial load-to-full load ratio by reducing the fan speed, which does not, of course, take place in direct proportion to the reduction of the fuel supply for the reasons shown.
However, the requirement to operate a heater with a high air ratio in the partial load range has the disadvantage that the excessive supply of combustion air leads to cooling of the flame and it consequently adversely affects burn-out. Another disadvantage is that the heater cannot be operated at partial loads lower than ca. 1/4, even though this is no longer sufficient for satisfying the increased demands on comfort. Ranges of 1:10 to 1:15 are now desirable especially in utility vehicles. For example, preheating the engine of a truck requires a heating output of 10 kW, whereas 1 kW is sufficient for heating the sleeping box.
An ultrasonic atomization burner of this class for air heaters of lower output for vehicles, in which heater combustion air is fed into the combustion space through air supply openings via an annular space surrounding the combustion chamber, has been known from DE 33,18,054 A1. Regardless of the type of fuel preparation (evaporative burners, mechanical atomizers, ultrasonic atomizers, etc.), it is not possible to operate these devices in partial load ranges below 1:4 with still acceptable combustion properties.
SUMMARY AND OBJECTS OF THE INVENTION
The basic object of the present invention is to provide a heater of this above mentioned type, which permits operation in a partial load range of at least 1:10 to 1:15 with good burn-out and low emission, regardless of the type of fuel preparation selected.
This object is attained based on the discovery that, if the air ratios are assumed to be similar to those occurring at full load, the rates at which the combustion air is admitted into the combustion chamber are not sufficient for achieving sufficient fuel-combustion air mixture formation, and that the combustion air must be influenced in such a way as to ensure that the rate of admission of the combustion air into the combustion chamber, which rate is necessary for good mixture formation, will still be reached even at an extremely low partial load.
This object is attained according to the present invention by dividing the annular space surrounding the combustion chamber in a heater of the above mentioned type into two compartments by a partition arranged approximately at right angles to the longitudinal axis of the combustion chamber and by connecting each of the compartments to an air supply line; by the combustion chamber wall having air passage openings, and by the combustion air being supplied to at least one of the air supply lines via a control element.
It is achieved with this arrangement that in partial load operation, after the necessary reduction of the amount of combustion air by reducing the fan speed, the air supply openings, which are located in the rear (downstream), are switched off, so that the remaining amount of air is supplied only through the air supply openings located in the front in the downstream direction. This air is admitted into the combustion chamber under a higher pressure and consequently at a higher rate, so that a better fuel-combustion air ratio and thus improved combustion will be obtained. It has proved to be particularly advantageous for the compartment of the annular space, which is the second compartment in the downstream direction, to be connected to the control element via an air supply line, and for the compartment of the annular space, which the first compartment in the downstream direction, to be connected to the combustion air line leading to the control element. A particularly simple and compact design with increased ease of control is thus obtained. A back-pressure-controlled control element, which has a simple design and operates particularly reliably under the given conditions of a heater, is preferably used as the control element. A further improvement can be achieved, according to a variant, by increasing the air passage cross sections in the combustion chamber wall in the downstream direction. This can be achieved either by increasing the number of air passage openings or by providing such openings with increasing cross section at equal number of openings.
The annular space which is the first annular space in the downstream direction may also surround the combustion chamber on the inlet side at least partially in the device according to the present invention, so that part of the air supplied can also enter the combustion chamber on the front side.
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 specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.
FIGS. 1 through 5 show a simplified and schematic representation of an exemplary embodiment, and the mode of operation will be described below wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a longitudinal sectional view through a combustion chamber with the combustion air supply;
FIG. 2 is a variant of a reversing valve;
FIG. 3 is a variant according to FIG. 2 with lateral discharge of the combustion air;
FIG. 4 is another variant of a reversing valve; and
FIG. 5 is a p-v (pressure-volume) diagram with characteristics and working points.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a combustion chamber 1, which is divided by an apertured partition 2 into a combustion chamber zone 1a, which is the front zone in the downstream direction, and a combustion chamber zone 16, which is the rear zone in the downstream direction. A flame tube 3 is connected to the combustion chamber 1. On the inlet side, the combustion chamber 1 has a combustion chamber bottom 4, on which a plate 5 made of absorbent and porous material, e.g., a nonwoven ceramic or metal wire knitted fabric, lies, via which the fuel supplied via the fuel supply line 6 is distributed for evaporation. The ignitable mixture in the combustion chamber 1 is ignited via a glow pin 7. An aperture 8, through which the flame is able to enter the flame tube 3, is arranged between the combustion chamber 1 and its the flame tube 3. In the combustion chamber wall 10, air passage openings 11a are arranged in the area of the combustion chamber zone 1a, and air passage openings 11b are arranged in the area of the combustion chamber zone 1b. The air passage cross section of the air passage openings 11a, 11b may increase in the downstream direction, either due to an increase in the number of the air passage openings 11a, 11b, or due to an increase in the cross sections, i.e., due to enlargement of the air passage openings 11a, 11a in the downstream direction. The combustion chamber 1 is surrounded by an annular space 9, which is divided by a partition 12 into a front compartment 9a, which is the front compartment in the downstream direction, and a compartment 9b, which is the rear compartment in the downstream direction.
The combustion air is supplied into the annular space 9 from the combustion air line 13 by means of a fan 14. The combustion air line 13 leads to a control element 15 and has a branch, which as an air supply line 16 is connected to the compartment 9a of the annular space 9, while the compartment 9b of the annular space 9, which is the rear compartment in the downstream direction, is connected to the control valve 15 via the air supply line 17.
The control element in this exemplary embodiment is designed as a pneumatic control valve and has a housing with a connection for the combustion air line 13 and with a connection for the air supply line 17. The housing accommodates a piston 18, which is designed as a step piston and closes and releases the connection for the combustion air line 13 with the step of smaller diameter D 1 , and it closes and releases the connection for the air supply line 17 with the step of larger diameter D 2 . The piston 18 acts against a spring 19; the housing also has vent openings 20.
FIG. 2 shows a variant of the control element, in which the piston 18 has a pot-shaped design and is provided with a circular sealing bead 21. In this embodiment, indifferent control states, which may lead to a disturbing valve chattering, are avoided in this design due to the step piston action, especially during reversal.
The variant of the control element 15 according to FIG. 3 shows a lateral connection of the air supply line 17, i.e., a connection that is offset by 90° compared with the combustion air line 13. Two cooperating control edges 22, 23 are now obtained. The two control edges 22, 23 release the influx to the air supply line 17 only when the effective pressure according to the resistance characteristic d according to FIG. 5 is admitted to the larger piston surface with the diameter D 2 , without a simultaneous release through the air passage openings 11b (shown in FIG. 1).
In one embodiment, not shown, this control element can act similarly to a pressure regulator if the diameter of the sealing bead is increased to the diameter of the piston. The two control edges define the control behavior by their shape and position, together with the force-displacement characteristic of the spring. Nearly the same pressures and consequently also the same inlet rates into the combustion chamber at full load and partial load can be preset with this embodiment.
In the preferred embodiment according to FIG. 4, the piston of the pneumatic control element 15 is replaced by a diaphragm 24, e.g., one made of rubber, which is pressed by the spring 19 onto a sealing seat 26 via a spring plate 25. To improve flexibility, the diaphragm 24 has at least one welt-like bead 27. The function corresponds to that of the exemplary embodiment according to FIG. 2.
The mode of action of the arrangement according to the present invention with the preferably automatically operating the control element 15 will be described below on the basis of FIG. 1.
Mode of Operation of Reversal
1. Starting Up the Heater Under Full Load:
After the fan 14 has been started up and the amount of air needed for full load is delivered, an excess pressure, which is determined essentially by the air passage openings 11a, develops over the piston surface D 1 . The pre-tension of the spring 19 is overcome, and the canal 17 is released. At the same time, the larger piston surface D 2 comes into action, and supports the piston's stroke movement, because the pressure acting on the piston 18 decreases due to the additional air passage openings 11b. The canal 17 thus remains wide open, and all of the air passage openings 11a, 11b are in action.
2. Reversal to Partial Load (e.g., to 1/10 the Rated Capacity):
The amount of air is reduced to, e.g., 1/5 by [reducing] the speed of the fan, and the amount of fuel is reduced to about 1/10 of the full-load value. As a result, according to p˜(V) 2 , the pressure will drop to very low values--to ≈1/25 in the example, the load on the piston will be released, and the canal 17 will be closed. Since only the air passage openings 11a act now, the pressure will again increase to a value which is independent of the ratio of cross section 11a to cross section 11b. The design should be selected to be such that the opening pressure described under 1 will not be reached. The opening 20 is used for ventilation on the rear side of the piston. Since only the openings 11a are in action for the entry of air, higher inlet velocities with improved mixture formation will occur compared with a conventional combustion chamber without air reversal.
3. Reversal to Full Load:
The control takes place as described under 1; the air passage openings 11b are again opened.
FIG. 5 shows the function of the control element 15 with the characteristics and the working points. Here,
a--shows the fan's delivery characteristic at full load,
b--shows the fan's delivery characteristic at partial load,
c--shows the resistance characteristic at full load,
d--shows the resistance characteristic at partial load,
A--shows the working point at full load,
B--shows the working point at partial load, and
C--shows the working point at partial load without a control element.
At full load (high fan speed), the working point A with the air volume V 2 +V 3 and the pressure p 1 becomes established at the intersection of the fan delivery characteristic a with the resistance characteristic c, which is defined primarily by the resistance of the total number of the air passage openings 11a and 11b (according to FIG. 1). After the fan speed and the amount of fuel have been reversed to the partial load operation, the partial-load working point B with the air volume V 2 and the pressure p 2 becomes established after automatic activation of the control element 15. The position of the partial-load resistance characteristic d is now determined essentially by the cross sections of the still remaining air passage openings 11a, i.e., the air passage openings 11b are switched off at partial load.
In contrast, only the substantially lower pressure p 2 ' and hence the working point C on the fan delivery characteristic c become established in the prior-art combustion chambers without the control element 15 and divided annular space 9. In the scale diagram, the pressure ratio is p 2 /p 2 ≃16, i.e., according to w˜√p, the velocity of the air entering the combustion chamber 1 through the air passage openings 11a is increased by a factor of about 4, which leads to substantially improved mixing of the fuel and combustion air and consequently to substantially better combustion.
The solution according to the present invention does not exclusively pertain to the example shown with an evaporative burner, but it is also applicable to other, prior-art combustion systems, to atomization burners, e.g., burners with ultrasonic atomization or pressure atomization.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
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A heater (independent vehicle heater) which can be operated in a particularly wide range between full load and partial load, e.g., 1:10 to 1:15, is shown. This is achieved by the annular space surrounding the combustion chamber being divided into two partial compartments and by supplying the combustion air to these partial compartments. A control element (back-pressure-controlled control element), which separates some of the air passage openings between the annular space and the combustion chamber from the passage of air, is arranged in the combustion air line.
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This application is a continuation of application Ser. No. 08/362,657, filed Dec. 22, 1994, now abandoned.
BACKGROUND OF THE INVENTION
1) Field of the Invention
The present invention relates to a compressed dry air supply system including an air compressor in which water is used as a cooling and lubricating medium for the movable parts of the air compressor.
2) Description of the Related Art
A compressed dry air supply system is used with a machine, such as an air-jet loom, in which a compressed and dehumidified air is needed. The compressed dry air supply system includes an air compressor into which air is introduced from the atmosphere and is compressed therein, and the compressed air discharged from the air compressor is fed to a dryer section to dehumidify the compressed air. The dryer section is provided with a mass of a hydroscopic agent, through which the compressed air is passed to dehumidify the compressed air. When the mass of hydroscopic agent is saturated with the absorbed moisture, the hydroscopic agent is recycled by passing compressed dry air through into the saturated mass of hydroscopic agent in the opposite direction or by heating it with a suitable heater. During the recycling of the mass of hydroscopic agent, the operation of the system must be interrupted.
An air compressor forming a part of the compressed dry air supply system includes various movable parts which must be sufficiently lubricated to prevent seizure of the movable parts, and which must be cooled because the movable parts are heated due to the adiabatic compression of air and due to the thermal energy produced by friction among the movable parts. In a compressed air supply system as shown in Unexamined Japanese Patent Publication No. 60(1985)-35196, an oil is used to lubricate and cool movable parts of a compressor included in this system, and compressed air discharged from the compressor is passed through an oil-separator in which oil drops are removed from the compressed air. Nevertheless, the compressed air discharged from the oil separator inevitably contains some oil as a fine oil mist. A compressed air containing oil is unacceptable in a machine such as the air-jet loom mentioned above.
Japanese Utility Model Publication No. 61(1958)-36798 discloses a compressed air supply system including an air compressor in which water is used as a cooling and lubricating medium for movable parts of the air compressor. In this system, the compressed air discharged from the air compressor contains fine water drops entrained therein, and is fed to an air tank having a water-separator by which the water drops are removed from the compressed air. Nevertheless, the compressed air obtained from the air tank is not necessarily dehumidified, and is very moist because it is saturated with water vapor. On the other hand, the water drops removed from the compressed air are accumulated in the air tank, and some of the accumulated water is successively returned to the air compressor for use as the lubricating and cooling medium for the movable parts of the air compressor. Nevertheless, a suitable amount of water must be periodically added to the system because a part of the water included in the system escapes therefrom as the water vapor in the compressed air discharged from the air tank and therefore from the system.
SUMMARY OF THE INVENTION
Therefore, an object of the present invention is to provide a compressed dry air supply system, including an air compressor, in which water is used as a lubricating and cooling medium for movable parts of the air compressor, which system is constituted such that the compressed air can be sufficiently dehumidified so that the addition of lubricating and cooling water to the system is unnecessary.
In accordance with an aspect of the present invention, there is provided a compressed dry air supply system comprising: an air compressor using water for lubricating and cooling the movable parts thereof; a refrigerator type dryer for dehumidifying a compressed air obtained from the air compressor; a water tank for receiving the water produced due to the dehumidification of the compressed air; and a recycling means for returning some of the water held in the water tank to the air compressor. The recycling means may include a conduit means provided between the water tank and the air compressor, and an upper space in the water tank is in communication with the conduit means to thereby prevent a rise in the air pressure in the upper space in the water tank. Preferably, the conduit means has a restrictor provided therein. Also, preferably, a conduit means is extended between the refrigerator type dryer and the water tank for feeding water from the refrigerator type dryer to the water tank, and has a restrictor provided therein. The water tank may be provided with an automatic drainage device for preventing a level of the water held therein from exceeding a given level.
In accordance with another aspect of the present invention, there is provided a compressed dry air supply system comprising: an air compressor using water for lubricating and cooling the movable parts thereof; a radiator for partially cooling the compressed air obtained from the air compressor; a water separator for removing water drops from the compressed air obtained from the radiator; a refrigerator type dryer for dehumidifying a compressed air obtained from the water separator; a water tank for receiving the water produced due to the removal of water from the compressed air by the water separator and the water produced due to the dehumidification of the compressed air by the refrigerator type dryer; and a recycling means for returning some of the water held in the water tank to the air compressor. The recycling means may include a conduit means provided between the water tank and the air compressor, and an upper space of the water tank is in communication with the conduit means to thereby prevent a rise in the air pressure in the upper space in the water tank. Preferably, the conduit means has a restrictor provided therein. Also, preferably, a conduit means is extended between the water separator and the water tank for feeding the water from the water separator to the water tank, and has a restrictor provided therein, and a conduit means is extended between the refrigerator type dryer and the water tank for feeding the water from the refrigerator type dryer to the water tank, and has a restrictor provided therein. The water tank may be provided with an automatic drainage device for preventing a level of the water held therein from exceeding a given level. Preferably, the radiator is provided with a fan so as to subject the radiatior to an air flow produced by the fan, and the air flow produced by the fan and passed through the radiator is directed onto water draining from the water tank, whereby the water drained by the drainage device can be quickly evaporated into atmosphere.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the present invention will be better understood from the following description, with reference to the accompanying drawing.
The drawing is a block diagram of a compressed dry air supply system according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the drawing, reference numeral 10 indicates an air compressor which may be a scroll type compressor, and which is operationally connected to a drive source such as an electric motor (not shown). The compressor 10 is connected to an air filter 12 through a suction conduit 14, and an air is introduced from the atmosphere into the compressor 10 through the air filter 12 and the conduit 14. A water-feeding conduit 16 is joined to the conduit 14, and water is fed from the conduit 16 into the air-stream passing through the conduit 14 so that the water is introduced together with the air into the compressor.
A discharge conduit 18 is extended from the compressor 10 to a radiator 20, and compressed air produced by the compressor 10 is fed to the radiator 20 through the conduit 18. The compressed air has a relatively high temperature due to the adiabatic compression of the air and due to the thermal energy produced by friction between the movable parts of the compressor 10, but it is suitably cooled by the radiator 20. As illustrated, preferably, the radiator 20 is provided with a cooling fan 22 so that the heat can be effectively removed from the radiator 20.
Then, the compressed air cooled by the radiator 20 is introduced into a well-known water separator 24 in which the water drops entrained with the compressed air are removed therefrom. Nevertheless, the compressed air from which the water drops are removed is very moist because it is saturated with water vapor. The water drops removed from the compressed air are fed to a water tank 26 through a conduit 28, and are accumulated therein.
The compressed air from which the water drops are removed is fed to a refrigerator type dryer 30 through a conduit 32 extended therebetween. The dryer 30 includes various well-known elements for establishing a refrigerating cycle, and these elements includes a compressor, a condenser, an expansion valve and an evaporator. The compressed air fed to the dryer 30 passes through a refrigerating zone which is formed and defined by the evaporator, and is thus rapidly chilled such that the saturated water vapor included therein is condensed as water drops, whereby the compressed air can be sufficiently dehumidified. The dryer 30 has a discharge conduit 34 extended therefrom, and is connected to a machine such as an air-jet loom 36. Namely, the air-jet loom 36 can be supplied with compressed and dehumidified air from the dryer 30 through the conduit 34. On the other hand, the water drops condensed in the refrigerating zone of the dryer 30 are fed to the water tank 26 through a conduit 38, are accumulated therein. Note, since the compressed air to be fed is partially dehumidified by the water separator 24, the capacity of the dryer 30 can be made small.
As illustrated, a conduit 40 is extended from a bottom of the water tank 26 to a solenoid valve 42, and then a conduit 44 is extended from the solenoid valve 42 and is connected to the water-feeding conduit 16 through a filter 46. The solenoid valve 42 is electrically connected to a timer controller 48 such that the solenoid valve 42 is periodically opened. Namely, a part of the water accumulated in the water tank 26 is periodically fed to the compressor 10.
The conduits 28 and 38 have restrictors 50 and 52 provided therein, respectively, and an upper space in the water tank 26 is in communication with the conduit 44 through a conduit 54 having a restrictor 56 provided therein. Thus, a rise in the air pressure in the upper space of the water tank 26 is suppressed so that the return of moist and wet air from that upper space to the water separator 24 and the dryer 30 can be prevented.
The air introduced from atmosphere into the compressor 10 contains water as water vapor, and this water is also removed from the compressed air by the dryer 30, so that the amount of the water accumulated in the water tank 26 is gradually increased. For this reason, the water tank 26 is provided with a well-known automatic drainage device 58 incorporated therein, so that a level of the water held in the water tank 26 cannot exceed a given level. Preferably, the air flow produced by the fan 22 and passed through the radiator 20 is directed onto the water draining from the water tank 26, as indicated by chain-dot lines in the drawing, whereby the draining water can be quickly evaporated into the atmosphere. Of course, in this case, a provision of piping for the water draining from the water tank 26 is unnecessary. Also, a size of the water tank 26 can be made small due to the automatic drainage device 58.
As is apparent from the foregoing, the compressed air discharged from the system according to the present invention is sufficiently dehumidified by the refrigerator type dryer 30, and thus an escape of water out of the system is substantially prevented. Accordingly, the system according to the present invention can be installed regardless of a location of a water service. Note, a conventional system, as disclosed in Japanese Utility Model Publication No. 61(1958)-36798, must be installed a location beside a water service because a suitable amount of water must be periodically added to the system.
Finally, it will be understood by persons skilled in the art that the foregoing description is of preferred embodiments of the present invention, and that various changes and modifications can be made without departing from the spirit and scope thereof.
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A compressed dry air supply system includes an air compressor which uses water for lubricating and cooling the movable parts thereof. Compressed air obtained from the compressor is sufficiently dehumidified by a refrigerator type dryer. The water produced due to the dehumidification of the compressed air is received in a water tank, and some of the water held in the water tank is recycled back to the compressor.
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CLAIM OF PRIORITY
[0001] The present application claims priority from Japanese patent application JP 2009-259429 filed on Nov. 13, 2009, the content of which is hereby incorporated by reference into this application.
FIELD OF THE INVENTION
[0002] This invention relates to a semiconductor device constructed with a system having a low power mode of reducing a consumed electric power formed on a semiconductor substrate and a data processing device constructed with the system mounted on its device enclosure, or a data processing device with a semiconductor integrated circuit constituting the system installed on a board, and more specifically, to a semiconductor device having a function of outputting a signal indicating, when the low power mode is not operating normally, that it does not operate normally from the system, and a data processing device.
BACKGROUND OF THE INVENTION
[0003] Conventionally, as a technology of reducing a power consumption in the data processing device, there was one that reduces a power consumption of the LSI by interrupting a power source inside the LSI (for example, refer to JP-A-2006-318513).
[0004] In addition, conventionally, as a technology of reducing the power consumption in the data processing device, there was one that reduces the power consumption of the LSI by altering a clock frequency supplied to the LSI (for example, refer to U.S. Pat. No. 7,082,579).
[0005] Still in addition, as a technology of cooling a data processing device having a semiconductor chip whose calorific power is large, conventionally there was one than adjusts a cooling capacity of cooling means by outputting a cooling means control signal depending on a power source variation signal that was outputted when the power source supplied to the semiconductor chip varied (for example, refer to US2003/0063437).
[0006] Even in addition, as a temperature detection circuit provided in the semiconductor chip, there was a technology whereby a signal was outputted before thermal shutdown was activated and an outside microcomputer etc. was enabled to use it by specifying a signal outputted by a temperature detection circuit in response to a detection temperature to be two-stage signals that corresponds to two-stage temperatures (for example, refer to JP-A-2003-108241).
SUMMARY OF THE INVENTION
[0007] In recent years, the power consumption of data processing devices increases and the power consumption poses a problem. Especially, the power consumption of the semiconductor integrated circuit (LSI: Large Scale Integrated circuit) for performing a data processing is increasing year by year in connection with improvement in processing performance and finer microfabrication of a semiconductor manufacturing process for manufacturing the LSI. In order to reduce this increasing power consumption, JP-A-2006-318513 discloses a technology of reducing the power consumption of the LSI by interrupting the power source inside the LSI. U.S. Pat. No. 7,082,579 discloses a technology of decreasing the power consumption of the LSI by altering the clock frequency supplied to the LSI.
[0008] An operation of interrupting the power source inside the LSI and an operation of lowering the clock frequency to reduce the electric power that are described above are called the low power mode. When a signal for shifting to the low power mode is generated outside the LSI or inside the LSI and is inputted into a circuit in the LSI, the circuit into which the signal is inputted shifts to the low power mode. Usually, in an apparatus on which the LSI is mounted, a supply capacity of the power source and performance of a cooling device for cooling the LSI are set in consideration of the electric power of the LSI. In doing this, in the case of using the LSI having the low power mode, settings of power source performance and cooling performance are done based on the premise that the LSI can shift to the low power mode and thereby the electric power can be reduced. Therefore, in the case where, although the LSI shifted to the low power mode by a certain factor, the electric power is not reduced actually (does not operate in the low power operation) , there arise problems such as: the power source will not be sufficiently supplied because power source performance and the cooling capacity are insufficient, and temperature of the LSI will rise more than assumption. When the power source is not fully supplied, it causes the LSI not to operate normally, and in addition brings about malfunctions of other parts, such as LSIs, mounted on the same board. Further, when the temperature increases, there arises a problem that the LSI deteriorates in performance and the LSI can no longer produce the performance of the LSI that is assumed. Therefore, when the LSI shifted to the low power mode and if the electric power does not decrease, it is necessary to take a measure such as halting the LSI, and exchanging the board on which the LSI is mounted.
[0009] Incidentally, although the technologies of US2003/0063437 and JP-A-2003-108241 described above do not aim at reduction of the power consumption and they differs from the present invention primarily in that point, it seems that some relevance exists among them at first sight in terms that a signal is outputted by detecting a variation of the power source of the data processing device or the semiconductor chip or a variation of the temperature thereof. However, both of these technologies have a problem that it is impossible to detect whether a desired action has actually occurred in response to the mode-switching signal, and therefore they should be discriminated clearly from the present invention that solves it. For example, although the technology of US2003/0063437, when the power source for supplying the semiconductor chip varies, adjusts the cooling capacity of the cooling means by outputting the cooling means control signal depending on the outputted power source variation signal, the data processing device only performs as far as outputting the cooling means control signal and cannot detect whether the cooling means is actually adjusted, so that alteration is produced in an operation of the cooling means. Moreover, the technology of JP-A-2003-108241 is one that outputs a signal prior to activation of the thermal shutdown, so that an outside microcomputer can use it by specifying a signal outputted by the temperature detection circuit depending on a detection temperature to be two-stage signals. The temperature detecting circuit provided in the interior of the semiconductor chip only performs as far as outputting two-stage signals, and cannot detect whether actions corresponding to these two-stage signals, especially thermal shutdown that is an action of the second stage, are actually activated.
[0010] Therefore, what is a goal of the present invention is to detect whether the electric power of the LSI is reduced actually when the LSI is shifted to the low power mode, and if the electric power is not reduced, a certain signal will be outputted.
[0011] One typical example of the present invention is as follows.
[0012] That is, the detection system of the present invention has a first operation mode corresponding to a first operation and a second operation mode corresponding to a second operation, and is characterized in that when a first signal for switching the first operation mode and the second operation mode is inputted and if it is detected that the operation is not switched between the first operation and the second operation, it performs a third operation.
[0013] Moreover, the semiconductor device of the present invention includes a circuit block for performing a predetermined processing on an inputted signal, and is characterized that the circuit block has a first operating state and a second operating state and have a function of, when the first signal for switching the first operation mode corresponding to the first operating state and the second operation mode corresponding to the second operating state is inputted, detecting that the operating state switched between the first operating state and the second operating state.
[0014] Furthermore, the data processing device of the present invention is configured with a semiconductor integrated circuit mounted thereon that has the first operating state and the second operating state, and is characterized that when the first signal for switching an operation mode of the semiconductor integrated circuit between the first operation mode corresponding to the first operating state and the second operation mode corresponding to the second operating state is inputted into the semiconductor integrated circuit and if the operating state does not change in response to a change of the operation mode, a second signal is outputted and the semiconductor integrated circuit shifts to a third operating state based on the second signal.
[0015] According to the present invention, it becomes possible to, when the LSI shifted to a low power mode and if the electric power is not successfully reduced for a certain reason, output to the outside that the electric power is not reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a schematic diagram of an internal structure of an LSI to which the present invention was applied;
[0017] FIG. 2 is an operation waveform of the LSI to which the present invention was applied;
[0018] FIG. 3 is an operational waveform of the LSI to which the present invention was applied;
[0019] FIG. 4 is a circuit diagram of a voltage comparator circuit;
[0020] FIG. 5 is a circuit diagram of a reference potential generating circuit;
[0021] FIG. 6 is a diagram showing an operation sequence of the LSI to which the present invention was applied;
[0022] FIG. 7 is a circuit block schematic diagram of an LSI to which the present invention was applied;
[0023] FIG. 8 is a schematic diagram of an information apparatus;
[0024] FIG. 9 is a circuit block schematic diagram of the LSI to which the present invention was applied;
[0025] FIG. 10 is a current change schematic diagram;
[0026] FIG. 11 is a temperature change schematic diagram;
[0027] FIG. 12 is a temperature change schematic diagram;
[0028] FIG. 13 is a temperature change schematic diagram;
[0029] FIG. 14 is a temperature change schematic diagram;
[0030] FIG. 15 is a schematic diagram of an internal structure of the LSI to which the present invention was applied;
[0031] FIG. 16 is a, diagram showing an operation waveform of the LSI to which the present invention was applied;
[0032] FIG. 17 is a diagram showing an operation waveform of the LSI to which the present invention was applied;
[0033] FIG. 18 is a diagram showing an operation waveform of the LSI to which the present invention was applied;
[0034] FIG. 19 is a diagram showing an operation waveform of the LSI to which the present invention was applied;
[0035] FIG. 20 is a schematic diagram of the internal structure of the LSI to which the present invention was applied;
[0036] FIG. 21 is a diagram showing an operation waveform of the LSI to which the present invention was applied; and
[0037] FIG. 22 is a diagram showing an operation waveform of the LSI to which the present invention was applied.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0038] A typical data processing device of the present invention has a function of measuring the electric power that an LSI consumes, and when the LSI shifts to a low power mode, measures the electric power that the LSI consumes. If the electric power is larger than the electric power of the low power mode that is assumed, it outputs a signal indicating that the electric power is not reduced in the low power mode.
[0039] More specifically, the detection system of the present invention has a first operation mode corresponding to a first operation and a second operation mode corresponding to a second operation, and, when a first signal for switching the first operation mode and the second operation mode is inputted and if the system detects that an operation is not switched between the first operation and the second operation, performs a third operation.
[0040] As the third operation, for example, an operation of outputting an alarm signal may be chosen, but the present invention is not limited to it.
[0041] As the first and second operations, for example, it can be configured that the first operation is an operation that uses a first electric power as a power consumption and the second operation is an operation that uses a second electric power larger than the first electric power as a power consumption, but the present invention is not limited to it.
[0042] Moreover, a semiconductor device of the present invention is equipped with a circuit block for performing a predetermine processing on an inputted signal, having a following function. That is, the circuit block has a first operating state and a second operating state, and has a function of, when the first signal for switching the first operation mode corresponding to the first operating state and the second operation mode corresponding to the second operating state is inputted, detecting that an operating state was switched between the first operating state and the second operating state.
[0043] The semiconductor device of the present invention will be suitable if it is configured to have a circuit for measuring the power consumptions of the first operating state and the second operating state. The circuit for measuring the power consumption can be specified to be, for example, a circuit for measuring a current of a power source, a circuit for measuring a potential of a power source line, or a circuit for measuring a temperature, but the present invention is not limited to them.
[0044] When the circuit for measuring a potential of the power source line is applied as the circuit for measuring the power consumption, the circuit for measuring the potential of the power source line may be specified as: a circuit for comparing an inputted reference potential and the voltage; a circuit for measuring a frequency of an oscillating circuit that is connected to the power source line; or a circuit for measuring the potential of the power source line depending on presence/absence of oscillation of the oscillating circuit connected to the power source line. However, the present invention is not limited to them.
[0045] When the circuit for measuring the temperature is applied as a circuit for measuring the power consumption, it is suitable to configure the circuit so that the electric powers of the first operating state and the second operating state may be measured by a comparison with a predetermined temperature. Alternatively, it is also suitable to configure the circuit so that variations of electric powers of the first operating state and the second operating state may be detected by variations of the temperatures measured by the circuit for measuring the temperature. Furthermore, it is suitable to configure the circuit so that those electric powers of the first operating state and the second operating state may be detected by a comparison between the temperature of the circuit being in the first operating state and the temperature of the circuit being in the second operating state. However, the present invention is not limited to these configurations.
[0046] Furthermore, the data processing device of the present invention is constructed with a semiconductor integrated circuit mounted thereon that has the first operating state and the second operating state, and has following characteristics. That is, when the first signal for switching an operation mode of the semiconductor integrated circuit between the first operation mode corresponding to the first operating state and the second operation mode corresponding to the second operating state is inputted into the semiconductor integrated circuit and if the operating state does not change in response to a change of the operation mode,, the second signal is outputted and the semiconductor integrated circuit shifts to a third operating state based on the second signal.
[0047] If the second signal is made to output from the semiconductor integrated circuit, it will be suitable. In that case, if the second signal is made to output based on the power consumption measured inside the semiconductor integrated circuit, it will be more suitable.
[0048] The third operating state can be, for example, an operating state of non-activating the semiconductor integrated circuit, or an operating state of generating a signal that urges replacement of the board on which the semiconductor integrated circuit is mounted, but the present invention is not limited to them.
[0049] The data processing device of the present invention will be suitable if it is configured to have a device for measuring the current of the power source that is supplied to the semiconductor integrated circuit and generate the second signal by a change of the current.
[0050] Hereafter, each of embodiments of the present invention will be described in detail using drawings.
FIRST EMBODIMENT
[0051] FIG. 1 shows a schematic diagram of an internal structure of the LSI that uses the present invention. In FIG. 1 , symbols indicate as follows: VDD is the power source line; PSW is a power source switch for interrupting the power source; PSOENB is a control signal for controlling the power source switch; VDCL is a local power source line capable of interrupting a supply of the power source; LOAD 1 is an operation circuit to which the local power source VDCL supplies the power source; REFGEN is a reference potential generating circuit; REFVOL is a reference potential signal; VCOMP is a voltage comparator circuit; VOUT is a signal representing a comparison result of the voltage comparator circuit VCOMP; LPTEST is a test circuit for testing a low voltage operation mode; COMPEN is a signal by which the LPTEST controls the VCOMP; and LPWRN is a signal of outputting whether the electric power is reduced at the time of the low voltage operation mode.
[0052] In this structure, when the operation circuit LOAD 1 is in operation, “L (low) ” is inputted Pinto the PSOENB and the power source switch PSW turns on. A potential of the VDCL becomes the same potential as that of the VDD, and the LOAD 1 operates normally. In this circuit, when the operation circuit LOAD 1 is not in operation, in order to reduce a leakage current of the LOAD 1 that is consumed even when being not in operation, the LOAD 1 is made to shift to the low power mode that interrupts the power source. When this circuit shifted to the low power mode, the PSOENB becomes “H (high) ” and the power source switch PSW turns off. By this, the potential of the VDCL falls and the leakage current flowing through the LOAD 1 can be reduced.
[0053] In this low power mode, if the VDCL potential does not fall due to a certain cause, the potential of the LOAD 1 does not fall, the leakage current continues flowing, and the electric power in the LOAD 1 cannot be reduced. Therefore, it is necessary to take a certain measure, such as halting this LSI, in the apparatus mounted with this LSI.
[0054] In the circuit of FIG. 1 , it becomes possible to judge whether the VDCL potential has fallen in the low power mode. In this circuit, upon output of a signal COMPEN for starting a test from the circuit LPTEST that tests a malfunction of the low power mode, the REFGEN generates the reference potential
[0055] REFVOL having a higher potential than the VDCL potential that is assumed when shifting to the low power mode, and simultaneously the voltage comparator circuit VCOMP compares the reference potential REFVOL and the potential of the VDCL and outputs its result as the VOUT. The LPTEST determines whether the LSI is in the low power mode and which is higher, the reference potential REFVOL or the VDCL potential. When the LSI is in the low power mode and the VDCL potential is higher than the reference potential, the LPTEST judges that there is the malfunction in the low power mode, and outputs the LPWRN.
[0056] FIG. 2 shows waveforms of respective parts of the circuit when there is no malfunction in the low power mode. At time START PSO, the PSOENB that is a signal instructing power source interruption changes from “H” to “L.” When the low power mode is operating normally, the power source switch is interrupted and the potential of the local power source VDCL falls from a VDD potential. At time CHECK VOL after a lapse of the fixed time after the power source interruption started, upon output of the COMPEN from the circuit LPTEST for verifying an operation of the low power mode, the potential of the VDCL and the reference potential REFVOL are compared. Since the potential of the VDCL is lower, the output VOUT of the voltage comparator circuit VCOMP becomes “H.” Therefore, in the low power mode, since the value of the VOUT has become “H,” and thereby it can be checked that the low power mode is operating normally, the output signal LPWRN of the LPTEST remains “L” as it was before.
[0057] FIG. 3 shows operation waveforms of respective parts of the circuit when there is the malfunction in the low power mode. At time START PSO, the PSOENB that is a signal instructing the power source interruption changes from “H” to “L.” If the low power mode is not operating normally, even after the PSOENB was inputted, the potential of the local power source VDCL will not fall lower than a fixed value. At time CHECK VOL after a lapse of the fixed time after the power source interruption started, upon output of the COMPEN from the circuit LPTEST for verifying an operation of the low power mode, the potential of the VDCL and the reference potential REFVOL are compared, and since the potential of the VDCL is higher, the output VOUT of the voltage comparator circuit VCOMP becomes “L.” Therefore, in the low power mode, since the value of the VOUT is “L” and thereby it can be checked that there is abnormality in the low power mode, the output signal LPWRN of the LPTEST becomes “H,” which is outputting that there is the abnormality in the low power mode.
[0058] FIG. 4 shows one example of a circuit configuration of the voltage comparator circuit VCOMP. This circuit is comprised of a current mirror, and when the COMPEN becomes “H, ” operates and compares the REFVOL and the potential of the VDCL. When the VDCL potential is lower, “H” is outputted from a terminal of the VOUT; when the VDCL potential is higher, “L” is outputted from the terminal of the VOUT.
[0059] FIG. 5 shows one example of a circuit configuration of the reference potential generating circuit REFGEN. In this circuit, resistances are connected in series and a potential of a portion to which the resistance is connected is outputted as the reference potential REFVOL. It becomes possible to easily form the resistance by an ON resistance or OFF resistance of a transistor, or a polysilicon resistance, or a metallic wiring resistance, or a resistance that uses a well or diffusion. Furthermore, in this circuit, a switch is connected to the resistance in series; the switch is controlled by the COMPEN and, only when voltage comparison is performed, turns on.
[0060] FIG. 6 shows a sequence of determining whether the low power mode of the LSI is normal using the present invention. In a normal operation mode, the circuit is performing a normal operation. After having shifted to the low power mode by the control signal, determination as to whether the electric power is successfully reduced is performed. If the electric power is successfully reduced normally, the circuit continues the low power mode as it was before. If the electric power is not successfully reduced, the circuit outputs the signal LPWRN indicating an alarm that the electric power is not successfully reduced in the low power mode.
[0061] FIG. 7 shows a schematic diagram of a circuit block of the LSI that uses the present invention. In FIG. 7 , symbols indicate as follow: CHIP is an LSI chip; PD 1 and PD 2 are power domains each of which is a circuit block to which the low power mode is applied, respectively; PSOENB 1 and PSOENB 2 are signals that control the power modes of the power domains PD 1 and PD 2 ; respectively; MODCONT is a control circuit for controlling the power mode; LPWRN 1 and LPWRN 2 are alarm signals when the low power modes of the power domains PD 1 and PD 2 are defective, respectively; WRNOUT is a circuit for outputting an alarm to outside the LSI chip when there is the malfunction in the low power modes of the PD 1 or PD 2 ; and LPWRNA is an alarm signal indicating that there is a low power mode malfunction in this LSI chip.
[0062] FIG. 7 shows an example to which the present invention is applied when there are plural power domains each of which becomes the low power mode inside the LSI. The operation mode of each power domain is controlled by the MODCONT and, for example, when letting the power domain PD 1 go into the low power mode, the PSOENB 1 is inputted. The inside of the PD 1 has the same configuration as FIG. 1 . It tests whether the low power mode is operating normally and, if there is the malfunction in the low power mode, outputs the LPWRN 1 . The WRNOUT is monitoring whether operations of the low power modes of the plural power domains are performing normally or abnormally, and, for example, when the alarm signal is outputted from the LPWRN 1 , outputs a signal indicating that there is a low power mode malfunction in this chip to outside the chip as the LPWRNA.
[0063] FIG. 8 schematically shows an example of an information apparatus that carries six boards each mounted with chips of FIG. 7 . This device carries boards BOARD 0 to BOARD 5 each mounted with two chips of FIG. 7 . For example, in case the low power mode malfunction occurs inside the LSI chip mounted on the BOARD 1 , the LSI chip outputs a signal indicating that there is the low power mode malfunction inside the chip as in FIG. 7 . In response to this signal, within the board, information that a chip having the malfunction in the low power mode is mounted inside the BOARD 1 is transmitted within the apparatus, and an action that urges replacement of the BOARD 1 out of this apparatus is taken (Exchange BOARD 1 ). Thereby, in the apparatus mounted with the LSI to which the present invention is applied, it becomes possible to prevent occurrence of a malfunction due to insufficiency of power source performance and heating of the apparatus due to insufficiency of cooling capacity.
[0064] In this embodiment, normality/abnormality of an operation of the low power mode, namely the power source interruption, is judged by measuring the potential of the power source that is interrupted. Therefore, in this embodiment, it becomes possible to detect failures of various power source interruptions such as short circuit of the power source VDD and the local power source VDCL, short circuit of the power source switch for interrupting the power source, and a defect of power source interruption control signal. Moreover, since a variation of the potential of the power source is detected in this embodiment, it is possible to use the present invention not only for the low power mode using the power source interruption but also for determination of operations, such as the low power mode of reducing the electric power by lowering the power source voltage.
[0065] As described above, the use of the present invention makes it possible to output an alarm in the case where the LSI having the low power mode shifted to the low power mode yet fails in reducing the electric power and to avoid performance deterioration and damage of the apparatus.
SECOND EMBODIMENT
[0066] FIG. 9 shows a schematic diagram of a circuit block of the LSI that uses the present invention. In FIG. 9 , symbols indicate as follow: CHIP is the LSI chip; PD 1 and PD 2 are the power domains each of which is a circuit block to which the low power mode is applied, respectively; PSOENB 1 and PSOENB 2 are the signals that control the power modes of the power domains PD 1 and PD 2 ; respectively; MODCONT is the control circuit for controlling the power mode; WRNOUT is the circuit for outputting an alarm to outside the LSI chip if there is the malfunction in the low power mode of the PD 1 or PD 2 ; and LPWRNA is the alarm signal indicating that there is the low power mode malfunction in this LSI chip. TEMP 1 and TEMP 2 are signals indicating temperature information in the power domains PD 1 and PD 2 , respectively. LPCHK is a circuit that judges whether there is the malfunction in the low power mode from information of the TEMP 1 and the TEMP 2 , and if there is the malfunction, outputs the alarm signal LPWRNA. TEMPMON is a thermometer for measuring a temperature inside the LSI.
[0067] Inside the LSI, if the low power mode is operating normally, the current decreases; contrary to this, if there is the malfunction in the low power mode, the width of decrease of the current when having shifted to the low power mode is small. FIG. 10 shows this situation. In FIG. 10 , “Normal” indicates the normal operation and “LP” indicates a low power operating state. When this current relationship exists, the temperature inside the LSI varies according to the flowing current. FIG. 11 shows a temperature relationship in this case. If the electric power is reduced normally in the low power mode, the temperature falls as compared with the case where the normal operation is being performed. Contrary to this, if there is the malfunction in the low power mode and the current does not decrease, a fall width of the temperature inside the LSI is also small. Thus, measurement of a temperature inside the chip enables to measure a flowing current in a pseudo manner. Therefore, when the signal of the PSOENB 1 is inputted into the LSI of FIG. 9 , the temperature inside the PD 1 is measured and the temperature is put into comparison to check whether the temperature there is reduced by a fixed amount or more. For example, when the temperature is lower than the TEMPTH in FIG. 11 , it can be judged that the low power mode is operating normally; conversely, when it is higher than the TEMPTH, it can be judged that the low power mode is not operating normally, and the alarm signal LPWRNA of FIG. 9 is outputted.
[0068] In this embodiment, since the current inside the LSI can be measured in a pseudo manner by measuring the temperature inside the LSI, it becomes possible to detect malfunctions of various low power modes, such as the power source interruption, the low voltage operation mode, and clock gating.
[0069] As described above, the use of the present invention makes it possible to output an alarm in the case where the LSI having the low power mode shifted to the low power mode yet fails in reducing the electric power and to avoid performance deterioration and damage of the apparatus.
THIRD EMBODIMENT
[0070] FIG. 12 shows a temperature measurement waveform in the case of detecting the malfunction of the low power mode by a control different from that of the second embodiment using the circuit of FIG. 9 . In FIG. 12 , “Normal” indicates the normal operation and “LP” indicates the low power mode. In FIG. 12 , if there is no malfunction in the low power mode, at the time of shifting from the normal operation to the low power mode, the temperature changes largely. Contrary to this, if there is the malfunction in the low power mode, a temperature change at the time of shifting from the normal operation to the low power mode is small.
[0071] Therefore, in the LSI of FIG. 9 , in the case of before and after inputting of the signal of the PSOENB 1 , measurement of the temperatures inside the PD 1 enables to determine whether the low power mode is operating normally , and if there is the malfunction in the low power mode, the alarm signal LPWRNA of FIG. 9 is outputted.
[0072] In this embodiment, since the current inside the LSI can be measured in a pseudo manner by measuring the temperature inside the LSI, it becomes possible to detect malfunctions of various low power modes, such as the power source interruption, the low voltage operation mode, and the clock gating.
[0073] As described above, the use of the present invention makes it possible to output an alarm in the case where the LSI having the low power mode shifted to the low power mode yet fails in reducing the electric power and to avoid performance deterioration and damage of the apparatus.
FOURTH EMBODIMENT
[0074] FIG. 13 and FIG. 14 show temperature measurement waveforms in the case of detecting the malfunction of the low power mode by a control different from that of the second embodiment using the circuit of FIG. 9 . The TEMP 1 and the TEMP 2 show temperatures of PSO 1 and PS 02 , respectively. This diagram shows a case where the PSO 2 is always performing the normal operation, and the PSO 1 performs the normal operation in the period of Normal and shifts to the low power mode in the period of LP. FIG. 13 shows a temperature state when there is no malfunction in the low power mode. In this case, when only the PSO 1 shifted to the low power mode, a difference in temperature between the PSO 1 and the PSO 2 is large. FIG. 14 shows a temperature state where there is the malfunction in the low power mode. In this case, even when only the PSO 1 shifted to the low power mode, the difference in temperature between the PSO 1 and the PSO 2 is small.
[0075] Therefore, in the LSI of FIG. 9 , comparison of the temperatures of the PD 1 and the PD 2 after the signal of the PSOENB 1 was inputted makes it possible to determine whether the low power mode is operating normally, and if there is the malfunction in the low power mode, the alarm signal LPWRNA of FIG. 9 will be outputted.
[0076] In this embodiment, since the current inside the LSI can be measured in a pseudo manner by measuring the temperature inside the LSI, it becomes possible to detect a malfunction of various low power modes, such as the power source interruption, the low voltage operation mode, and the clock gating.
[0077] As described above, the use of the present invention makes it possible to output an alarm in the case where the LSI having the low power mode shifted to the low power mode yet fails in reducing the electric power and to avoid performance deterioration and damage of the apparatus.
FIFTH EMBODIMENT
[0078] FIG. 15 shows a schematic diagram of an internal structure of the LSI that uses the present invention. In FIG. 15 , symbols indicate as follows: VDDL is a power source line of 0.8 V; VDDH is a power source line of 1.0 V; LVSW is a signal line for controlling a switch of a low voltage power source; HVSW is a signal line for controlling a switch of a high voltage power source; VDCL is a local power source line capable of switching a power source voltage; LOAD 1 is an operation circuit to which a power source is supplied by the local power source VDCL; LPTEST is a test circuit for testing the low voltage operation mode; DUMRO is a ring oscillator module; DUMCLK is an output signal of the DUMRO; REFCLK is a reference clock; PHCOMP is a frequency comparator circuit; and LPWRN is a signal of outputting whether the electric power is reduced at the time of the low voltage operation mode.
[0079] In this structure, when operating the operation circuit LOAD 1 at high speed, a high voltage is impressed to the LOAD 1 by connecting the local power source VDCL to the power source VDDH of a high voltage (1.0 V) with the HVSW set to “L” and the LVSW set to “H.” Moreover, when the LOAD 1 does not need a high operation speed, a low voltage is impressed to the LOAD 1 by connecting the local power source VDCL to the power source VDDL of a low voltage (0.8 V) with the HVSW set to “H” and the LVSW set to “L,” and therefore it becomes possible to reduce the electric power although the operation speed of the LOAD 1 becomes slow.
[0080] In this circuit, when being in the low power mode, namely when the potential of the local power source is set to 0.8 V, if the VDCL potential does not fall from 1.0 V due to a certain cause, the potential of the LOAD 1 will not fall and the power consumption of the LOAD 1 cannot be reduced. Therefore, it is necessary to take a certain measure of halting this LSI or the like in an apparatus mounted with this LSI.
[0081] In the circuit of FIG. 1 , it becomes possible to judge whether the VDCL potential has fallen in the low power mode. In this circuit, in the circuit LPTEST for testing the malfunction of the low power mode, when having shifted to the low power mode due to the signals LVSW and HVSW each for controlling the power source switch, an output of the DUMRO that is a dummy ring oscillator and a frequency of the reference clock REFCLK are compared and its output is inputted into the LPTEST. Since the dummy ring oscillator is supplied the power source from the local power source VDCL, the frequency outputted from it fluctuates depending on the potential of the VDCL. Therefore, when the potential of the local power source VDCL has not fallen lower than a certain fixed voltage, the ring oscillator operates at a speed faster than a setup frequency. If the frequency of the reference clock is set to a somewhat higher frequency than a frequency at which the dummy ring oscillator operates with a low power source voltage, it will become possible to judge whether the VDCL potential has fallen to 0.8 V, namely whether the low power mode is operating normally.
[0082] FIG. 16 shows operation waveforms of respective parts of the circuit when there is no malfunction in the low power mode. At time START_LV, in order to set the local power source potential to a low voltage, the HVSW changes from “L” to “H,” and the LVSW changes from “H” to “L.” When the low power mode is operating normally, the potential of the local power source VDCL falls to 0.8 V. At time CHECK_F after a lapse of a fixed time after the power source voltage changed, comparison between the output of the DUMRO and the frequency of the reference clock REFCLK enables to check that the low power mode is operating normally because a frequency of the DUMCLK is low, and the output signal LPWRN of the LPTEST remains “L” as it was before.
[0083] FIG. 17 shows operation waveforms of respective parts of the circuit when there is the malfunction in the low power mode. At time START_LV, in order to set the local power source potential to a low voltage, the HVSW changes from “L” to “H,” and the LVSW changes from “H” to “L.” Since the low power mode is not operating normally, the potential of the local power source VDCL does not fall to 0.8 V. At time CHECK_F after a lapse of a fixed time after the power source voltage changed, comparison of the output of the DUMRO and a frequency of the REFCLK shows that the frequency of the DUMCLK is higher, which reveals that there is the malfunction in the low power mode, and the output signal LPWRN of the LPTEST becomes “H.”
[0084] Although the frequency comparator circuit is not shown here, it can be easily formed with a circuit for counting the number of times of rise of the clock inputted in a fixed time.
[0085] Moreover, in this circuit configuration, the low power mode of interrupting the power source can be performed by interrupting switches that connect the local power source and the power sources VDDL and VDDH.
[0086] FIG. 18 shows operation waveforms of respective parts of the circuit when there is no malfunction in the power source interruption. At time START_PSO, in order to interrupt the power source of the local power source potential, the HVSW changes from “L” to “H”, and the LVSW maintains “H.” When the power source interruption is operating normally, the potential of the local power source VDCL falls to near 0 V, and checking of the output of the DUMRO at time CHECK_F after a lapse of a fixed time after the power source interruption started shows that the DUMCLK performs no clock operation and thereby it can be checked that the low power mode is operating normally, and the output signal LPWRN of the LPTEST remains “L” as it was before.
[0087] FIG. 19 shows operation waveforms of respective parts of the circuit when there is the malfunction in the power source interruption. At time START_PSO, in order to interrupt the power source of the local power source potential, the HVSW changes from “L” to “H,” and the LVSW maintains “H.” If there is a defect in a power source interrupting circuit, the potential of the local power source VDCL does not fall, and at time CHECK_F after a lapse of a fixed time after interruption of the power source started, checking of the output of the DUMRO reveals that the DUMCLK is performing a clock operation. In this case, the low power mode does not operate normally and the output signal LPWRN of the LPTEST becomes “H.”
[0088] In this embodiment, normality/abnormality of an operation of the low power mode, namely the low voltage operation or the power source interception, is judged by measuring the potential of the local power source by a measurement of a frequency of the dummy ring oscillator. Therefore, in this embodiment, it becomes possible to detect failures of various power source interruptions such as short circuit of the power source VDD and the local power source VDCL, short circuit of the power source switch for interrupting the power source, and a malfunction of the power source interruption control signal.
[0089] As described above, the use of the present invention makes it possible to output an alarm in the case where the LSI having the low power mode shifted to the low power mode yet fails in reducing the electric power and thereby to avoid performance deterioration and damage of the apparatus.
SIXTH EMBODIMENT
[0090] FIG. 20 shows the LSI that uses the present invention and a circumferential structure thereof. In FIG. 20 , symbols indicate as follow: CHIP is the LSI chip; CMEAS is an ammeter; LPMODE is a signal that shifts the mode to the low power mode;
[0091] and LPWRNA is a signal indicating the low power mode malfunction.
[0092] In this circuit, when the LSI shifted to the low power mode, if there is the malfunction in the low power mode due to a certain cause, the electric power consumed by the CHIP cannot be reduced.
[0093] FIG. 21 shows waveforms of respective parts of the circuit when there is no malfunction in the low power mode. At time START_LV, in order to make the CHIP shift to the low power mode, the LPMODE changes from “L” to “H.” When the low power mode is operating normally, the current I(VDD) of the power source falls, and at time CHECK_I after a lapse of the fixed time after the power source voltage changed, measurement of the current enables to check that the low power mode is operating normally, and the LPWRN remains “L” as it was before.
[0094] FIG. 22 shows an operation waveform of respective parts of the circuit when there is the malfunction in the low power mode. At time START_LV, in order to make the CHIP shift to the low power mode, the LPMODE changes from “L” to “H.” If there is the malfunction in the low power mode, the current I(VDD) of the power source does not fall, and at time CHECK_I after a lapse of the fixed time after the power source voltage changed, measurement of the current checks that there is the malfunction in the low power mode, and the LPWRN remains “H” as it was before.
[0095] In this embodiment, normality/abnormality of the low power mode that is the low voltage operation or the power source interruption is judged by directly measuring a current consumed by the LSI. Therefore, in this embodiment, it ,becomes possible to detect failures of various low power modes.
[0096] As described above, the use of the present invention makes it possible to output an alarm in the case where the LSI having the low power mode shifted to the low power mode yet fails in reducing the electric power and to avoid performance deterioration and damage of the apparatus.
[0097] Moreover, the use of the present invention makes it possible to take a measure of halting the device and the like in the data processing device in case the electric power is consumed more than a design value.
[0098] According to each of the above-mentioned embodiments of the present invention, it becomes possible to, when the LSI shifted to the low power mode and if the electric power is not successfully reduced, output that the electric power fails to be reduced to the outside. Furthermore, by outputting the signal to the outside, it becomes possible to prevent the insufficiency of electric power supply of the apparatus mounted with the LSI. Furthermore, by outputting the signal to the outside, it becomes possible to prevent deterioration of the performance of the LSI and deterioration of the performance of the apparatus mounted with the LSI.
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To provide an LSI having a low power mode that can prevent an apparatus on which the LSI is mounted from resulting in performance degradation, etc. even when its electric power is not reduced in the low power mode. Devised is a circuit that instructs an operation mode and detects whether the LSI operates as specified by the mode, and that measures a current at the time of the low power mode in a pseudo manner and, if despite having shifted to the low power mode, the current is not reduced actually, issues an alarm signal.
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STATEMENT OF PRIORITY
[0001] This application claims priority under 35 USC Section 119 to Provisional Patent Application Ser. Nos. 60/947,253 filed Jun. 29, 2007 and 61/037,946 filed Mar. 19, 2008, the disclosures of which are hereby incorporated by reference in their entireties.
FIELD OF THE INVENTION
[0002] This invention provides methods for predicting and diagnosing ovarian cancer, particularly epithelial ovarian cancer, and it further provides associated analytical reagents, diagnostic models, test kits and clinical reports.
BACKGROUND
[0003] The American Cancer Society estimates that ovarian cancer will strike 22,430 women and take the lives of 15,280 women in 2007 in the United States. Ovarian cancer is not a single disease, however, and there are actually more than 30 types and subtypes of ovarian malignancies, each with its own pathology and clinical behavior. Most experts therefore group ovarian cancers within three major categories, according to the kind of cells from which they were formed: epithelial tumors arise from cells that line or cover the ovaries; germ cell tumors originate from cells that are destined to form eggs within the ovaries; and sex cord-stromal cell tumors begin in the connective cells that hold the ovaries together and produce female hormones.
[0004] Common epithelial tumors begin in the surface epithelium of the ovaries and account for about 90 percent of all ovarian cancers in the U.S. (and the following percentages reflect U.S. prevalence of these cancers). They are further divided into a number of subtypes—including serous, endometrioid, mucinous, and clear cell tumors—that can be further subclassified as benign or malignant tumors. Serous tumors are the most widespread forms of ovarian cancer. They account for 40 percent of common epithelial tumors. About 50 percent of these serous tumors are malignant, 33 percent are benign, and 17 percent are of borderline malignancy. Serous tumors occur most often in women who are between 40 and 60 years of age.
[0005] Endometrioid tumors represent approximately 20 percent of common epithelial tumors. In about 20 percent of individuals, these cancers are associated with endometrial carcinoma (cancer of the womb lining). In 5 percent of cases, they also are linked with endometriosis, an abnormal occurrence of endometrium (womb lining tissue) within the pelvic cavity. The majority (about 80 percent) of these tumors are malignant, and the remainder (roughly 20 percent) usually is borderline malignancies. Endometrioid tumors occur primarily in women who are between 50 and 70 years of age.
[0006] Clear cell tumors account for about 6 percent of common epithelial tumors. Nearly all of these tumors are malignant. Approximately one-half of all clear cell tumors are associated with endometriosis. Most patients with clear cell tumors are between 40 and 80 years of age.
[0007] Mucinous tumors make up about 1 percent of all common epithelial tumors. Most (approximately 80 percent) of these tumors are benign, 15 percent are of borderline malignancy, and only 5 percent are malignant. Mucinous tumors appear most often in women between 30 to 50 years of age.
[0008] Ovarian cancer is by far the most deadly of gynecologic cancers, accounting for more than 55 percent of all gynecologic cancer deaths. But ovarian cancer is also among the most treatable—if it is caught early. When ovarian cancer is caught early and appropriately treated, the 5-year survival rate is 93 percent. See, for example, Luce et al, “Early Diagnosis Key to Epithelial Ovarian Cancer Detection,” The Nurse Practitioner, December 2003 at p. 41. Extensive background information about ovarian cancer is readily available on the internet, for example, from the “Overview: Ovarian Cancer” of the Cancer Reference Information provided by the American Cancer Society (www.cancer.org) and the NCCN Clinical Practice Guidelines in Oncology™ Ovarian Cancer V.1.2007 (www.nccn.org).
[0009] The current reality for the diagnosis of ovarian cancer is that most cases—81 percent of all cases of ovarian cancer—are not caught in earliest stage. This is because early stage ovarian cancer is very difficult to diagnose. Its symptoms may not appear or be noticed at this point. Or, symptoms—such as bloating, indigestion, diarrhea, constipation and others—may be vague and associated with many common and less serious conditions. Most importantly, there has been no effective test for early detection. An effective tool for early and accurate detection of ovarian cancer is a critical unmet medical need.
Biomarkers for Ovarian Cancer
[0010] A variety of biomarkers to diagnose ovarian cancer have been proposed, and elucidated through a variety of technology platforms and data analysis tools. An interesting compilation of 1,261 potential protein biomarkers for various pathologies was presented by N. Leigh Anderson et al., “A Target List of Candidate Biomarkers for Targeted Proteomics,” Biomarker Insights 2:1-48 (2006). A spreadsheet listing the markers discussed in this paper can be found at the website of the Plasma Proteome Institute (http://www.plasmaproteome.org). Several published studies are described immediately below and a number of other studies are listed as references at the end of this specification. All of these studies, all other documents cited in this specification, and related provisional patent application Ser. Nos. 60/947,253 filed Jun. 29, 2007 and 61/037,946 filed Mar. 19, 2008, are hereby incorporated by reference in their entireties.
[0011] For example, Cole, “Methods for detecting the onset, progression and regression of gynecologic cancers,” U.S. Pat. No. 5,356,817 (Oct. 18, 1994) described a method for detecting the presence of a gynecologic cancer in a female, said cancer selected from the group consisting of cervical cancer, ovarian cancer, endometrial cancer, uterine cancer and vulva cancer, the method comprising the steps of: (a) assaying a plasma or tissue sample from the patient for the presence of CA 125, and at or about the same time; and (b) assaying a bodily non-blood sample from said patient for the presence of human chorionic gonadotropin beta-subunit core fragment, wherein the detection of both CA 125 and human chorionic gonadotropin beta-subunit core fragment is an indication of the presence of a gynecological cancer in the female. A measurement of the human chorionic gonadotropin beta-subunit core fragment alone was stated to be useful in monitoring progression and regression of such cancers.
[0012] Fung et al, “Biomarker for ovarian and endometrial cancer: hepcidin,” U.S. Patent Application 20070054329, published Mar. 8, 2007, describes a method for qualifying ovarian and endometrial cancer status based on measuring hepcidin as a single biomarker, and based on panels of markers including hepcidin plus transthyretin, and those two markers plus at least one biomarker selected from the group consisting of: Apo A1, transferrin, CTAP-III and ITIH4 fragment. An additional panel further includes beta-2 microglobulin. These biomarkers were measured by mass spectrometry, particularly SELDI-MS or by immunoassay. And data was analyzed by ROC curve analysis.
[0013] Fung et al. also described the use of hepcidin levels used in combination with other biomarkers, and concluded that the predictive power of the test was improved. More specifically, increased levels of hepcidin together with decreased levels transthyretin were correlated with ovarian cancer. Increased levels of hepcidin together with decreased levels of transthyretin, together with levels of one or more of Apo A1 (decreased level), transferrin (decreased level), CTAP-III (elevated level) and an internal fragment of ITIH4 (elevated level) were also correlated with ovarian cancer. The foregoing biomarkers were to further be combined with beta-2 microglobulin (elevated level), CA125 (elevated level) and/or other known ovarian cancer biomarkers for use in the disclosed diagnostic test. And hepcidin was said to be hepcidin-25, transthyretin was said to be cysteinylated transthyretin, and/or ITIH4 fragment perhaps being the ITIH4 fragment 1.
[0014] Diamandis, “Multiple marker assay for detection of ovarian cancer,” U.S. Patent Application 20060134120 published Jun. 22, 2006, described a method for detecting a plurality of kallikrein markers associated with ovarian cancer and optionally CA125, wherein the kallikrein markers comprise or are selected from the group consisting of kallikrein 5, kallikrein 6, kallikrein 7, kallikrein 8, kallikrein 10, and kallikrein 11. His patent application explained that a significant difference in levels of these kallikreins, which are a subgroup of secreted serine proteases markers, and optionally that also of CA125, relative to the corresponding normal levels, was indicative of ovarian cancer. By repeatedly sampling these markers in the same patient over time, Diamandis also found that a significant difference between the levels of the kallikrein markers, and optionally CA125, in a later sample, relative to an earlier sample, is an indication that a patient's therapy is efficacious for inhibiting ovarian cancer. Samples were evaluated by protein binding techniques, for example, immunoassays, and by nucleotide array, PCR and the like techniques.
[0015] Gorelik et al, Multiplexed Immunobead-Based Cytokine Profiling for Early Detection of Ovarian Cancer” in Cancer Epidemiol Biomarkers Prev. 2005:14(4) 981-7 (April 2005) reported that a panel of multiple cytokines that separately may not show strong correlation with the disease provide diagnostic potential. A related patent application appears to be Lokshin et al., “Multifactorial assay for cancer detection,” U.S. Patent Application 20050069963 published Mar. 31, 2005. According to the journal article, a novel multianalyte LabMAP profiling technology was employed that allowed simultaneous measurement of multiple markers. Various concentrations of 24 cytokines (cytokines/chemokines, growth, and angiogenic factors) in combination with CA-125 were measured in the blood sera of 44 patients with early-stage ovarian cancer, 45 healthy women, and 37 patients with benign pelvic tumors.
[0016] Of the cytokines discussed by Gorelik et al., six markers, specifically interleukin (IL)-6, IL-8, epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), monocyte chemoattractant protein-1 (MCP-1), together with CA-125, showed significant differences in serum concentrations between ovarian cancer and control groups. Out of those markers, IL-6, IL-8, VEGF, EGF, and CA-125, were used in a classification tree analysis that reportedly resulted in 84% sensitivity at 95% specificity. The receiver operator characteristic curve (ROC) described using the combination of markers produced sensitivities between 90% and 100% and specificities of 80% to 90%. Interestingly, the receiver operator characteristic curve for CA-125 alone resulted in sensitivities of 70% to 80%. The classification tree analysis described in the paper for discrimination of benign condition from ovarian cancer used CA-125, granulocyte colony-stimulating factor (G-CSF), IL-6, EGF, and VEGF which resulted in 86.5% sensitivity and 93.0% specificity. The authors concluded that simultaneous testing of a panel of serum cytokines and CA-125 using LabMAP technology presented a promising approach for ovarian cancer detection.
[0017] A related patent application by Lokshin, “Enhanced diagnostic multimarker serological profiling,” U.S. Patent Application 20070042405 published Feb. 22, 2007 describes various biomarker panels and associated methods for diagnosis of ovarian cancer. One method involves determining the levels of at least four markers in the blood of a patient, where at least two different markers are selected from CA-125, prolactin, HE4 (human epididymis protein 4), sV-CAM and TSH; and where a third marker and a fourth marker are selected from CA-125, prolactin, HE4, sV-CAM, TSH, cytokeratin, sl-CAM, IGFBP-1, eotaxin and FSH, where each of the third marker and fourth marker selected from the above listed markers is different from each other and different from either of the first and second markers, and where dysregulation of at least the four markers indicates high specificity and sensitivity for a diagnosis of ovarian cancer. Another panel includes at least eight markers in the blood of a patient, wherein at least four different markers are selected from the group consisting of CA-125, prolactin, HE4, sV-CAM, and TSH and wherein a fifth marker, a sixth marker, a seventh marker and an eighth marker are selected from the group consisting of CA-125, prolactin, HE4, sV-CAM, TSH, cytokeratin, sI-CAM, IGFBP-1, eotaxin and FSH, and further wherein each of said fifth marker, said sixth marker, said seventh marker and said eighth marker is different from the other and is different from any of said at least four markers, wherein dysregulation of said at least eight markers indicates high specificity and sensitivity for a diagnosis of ovarian cancer.
[0018] The Lokshin (2007) patent application also describes a blood marker panel comprising two or more of EGF (epidermal growth factor), G-CSF (granulocyte colony stimulating factor), IL-6, IL-8, CA-125 (Cancer Antigen 125), VEGF (vascular endothelial growth factor), MCP-1 (monocyte chemoattractant protein-1), anti-IL6, anti-IL8, anti-CA-125, anti-c-myc, anti-p53, anti-CEA, anti-CA 15-3, anti-MUC-1, anti-survivin, anti-bHCG, anti-osteopontin, anti-PDGF, anti-Her2/neu, anti-Aktl, anti-cytokeratin 19, cytokeratin 19, EGFR, CEA, kallikrein-8, M-CSF, FasL, ErbB2 and Her2/neu in a sample of the patient's blood, where the presence of two or more of the following conditions indicated the presence of ovarian cancer in the patient: EGF (low), G-CSF (high), IL-6 (high), IL-8 (high), VEGF (high), MCP-1 (low), anti-IL-6 (high), anti-IL-8 (high), anti-CA-125 (high), anti-c-myc (high), anti-p.sup.53 (high), anti-CEA (high), anti-CA 15-3 (high), anti-MUC-1 (high), anti-survivin (high), anti-bHCG (high), anti-osteopontin (high), anti-Her2/neu (high), anti-Aktl (high), anti-cytokeratin 19 (high), anti-PDGF (high), CA-125 (high), cytokeratin 19 (high), EGFR (low, Her2/neu (low), CEA (high), FasL (high), kallikrein-8 (low), ErbB2 (low) and M-CSF (low). Exemplary panels include, without limitation: CA-125, cytokeratin-19, FasL, M-CSF; cytokeratin-19, CEA, Fas, EGFR, kallikrein-8; CEA, Fas, M-CSF, EGFR, CA-125; cytokeratin 19, kallikrein 8, CEA, CA 125, M-CSF; kallikrein-8, EGFR, CA-125; cytokeratin-19, CEA, CA-125, M-CSF, EGFR; cytokeratin-19, kallikrein-8, CA-125, M-CSF, FasL; cytokeratin-19, kallikrein-8, CEA, M-CSF; cytokeratin-19, kallikrein-8, CEA, CA-125; CA 125, cytokeratin 19, ErbB2; EGF, G-CSF, IL-6, IL-8, VEGF and MCP-1; anti-CA 15-3, anti-IL-8, anti-survivin, anti-p53 and anti c-myc; anti-CA 15-3, anti-IL-8, anti-survivin, anti-p53, anti c-myc, anti-CEA, anti-IL-6, anti-EGF; and anti-bHCG.
[0019] Chan, et al., “Use of biomarkers for detecting ovarian cancer,” U.S. Published Patent Application 20050059013, published Mar. 17, 2005 describes a method of qualifying ovarian cancer status in a subject comprising: (a) measuring at least one biomarker in a sample from the subject, wherein the biomarker is selected from the group consisting of ApoA1, transthyretin .DELTA.N10, IAIH4 fragment, and combinations thereof, and (b) correlating the measurement with ovarian cancer status.
[0020] Another embodiment in the Chan application described an additional biomarker selected from CA125, CA125 II, CA15-3, CA19-9, CA72-4, CA 195, tumor associated trypsin inhibitor (TATI), CEA, placental alkaline phosphatase (PLAP), Sialyl TN, galactosyltransferase, macrophage colony stimulating factor (M-CSF, CSF-1), lysophosphatidic acid (LPA), 110 kD component of the extracellular domain of the epidermal growth factor receptor (p110EGFR), tissue kallikreins, for example, kallikrein 6 and kallikrein 10 (NES-1), prostasin, HE4, creatine kinase B (CKB), LASA, HER-2/neu, urinary gonadotropin peptide, Dianon NB 70/K, Tissue peptide antigen (TPA), osteopontin and haptoglobin, and protein variants (e.g., cleavage forms, isoforms) of the markers.
[0021] An ELISA-based blood serum test described the evaluation of four proteins useful in the early diagnosis of epithelial ovarian cancer (leptin, prolactin, osteopontin and insulin-like growth factor). The authors reported that no single protein could completely distinguish the cancer group from the healthy control group. However, the combination of these four proteins provided sensitivity 95%, positive predictive value (PPV) 95%, specificity 95%, and negative predictive value (NPV) 94%, which was said to be a considerable improvement on current methodology. Mor et al., “Serum protein markers for early detection of ovarian cancer,” PNAS (102:21) 7677-7682 (2005).
[0022] A related patent application by Mor et al. “Identification of Cancer Protein Biomarkers Using Proteomic Techniques,” U.S. Patent Application 2005/0214826, published Sep. 29, 2005 describes biomarkers identified by using a novel screening method. The biomarkers are stated to discriminate between cancer and healthy subjects as well as being useful in the prognosis and monitoring of cancer. Specifically, the abstract of the patent application relates to the use of leptin, prolactin, OPN and IGF-II for these purposes. The disclosed invention is somewhat more generally characterized as involving the comparison of expression of one or more biomarkers in a sample that are selected from the group consisting of: 6Ckine, ACE, BDNF, CA125, E-Selectin, EGF, Eot2, ErbB1, follistatin, HCC4, HVEM, IGF-II, IGFBP-1, IL-17, IL-1srII, IL-2sRa, leptin, M-CSF R, MIF, MIP-1a, MIP3b, MMP-8, MMP7, MPIF-1, OPN, PARC, PDGF Rb, prolactin, ProteinC, TGF-b RIII, TNF-R1, TNF-a, VAP-1, VEGF R2 and VEGF R3. A significant difference in the expression of these one or more biomarkers in the sample as compared to a predetermined standard of each is said to diagnose or aid in the diagnosis of cancer.
[0023] A patent application by Le Page et al. “Methods of Diagnosing Ovarian Cancer and Kits Therefor,” WO2007/030949, published Mar. 22, 2007 describes a method for determining whether a subject is affected by ovarian cancer by detecting the expression levels of FGF-2 and CA125 and, optionally, IL-18.
[0024] Other approaches described in the patent and scientific literature include the analysis of expression of particular gene transcripts in blood cells. See, for example, Liew, “Method for the Detection of Cancer Related Gene Transcripts in Blood,” U.S. Published Patent Application 2006/0134637, Jun. 22, 2006. Although gene transcripts specific for ovarian cancer are not identified, transcripts from Tables 3J, 3K and 3X are said to indicate the presence of cancer. See also, Tchagang et al., “Early Detection of Ovarian Cancer Using Group Biomarkers,” Mol. Cancer Ther. (1):7 (2008).
[0025] Another diagnostic approach involves detecting circulating antibodies directed against tumor-associated antigens. See, Nelson et al. “Antigen Panels and Methods of Using the Same,” U.S. Patent Application 2005/0221305, published Oct. 6, 2005; and Robertson “Cancer Detection Methods and Regents,” U.S. Patent Application 2003/0232399, published Dec. 18, 2003.
[0026] What has been urgently needed in the field of gynecologic oncology is a minimally invasive (preferably serum-based) clinical test for assessing and predicting the presence of ovarian cancer that is based on a robust set of biomarkers and sample features identified from a large and diverse set of samples, together with methods and associated computer systems and software tools to predict, diagnose and monitor ovarian cancer with high accuracy at its various stages.
SUMMARY OF THE INVENTION
[0027] The present invention generally relates to cancer biomarkers and particularly to biomarkers associated with ovarian cancer. It provides methods to predict, evaluate diagnose, and monitor cancer, particularly ovarian cancer, by measuring certain biomarkers, and further provides a set or array of reagents to evaluate the expression levels of biomarkers that are associated with ovarian cancer. A preferred set of biomarkers provides a detectable molecular signature of ovarian cancer in a subject. The invention provides a predictive or diagnostic test for ovarian cancer, particularly for epithelial ovarian cancer and more particularly for early-stage ovarian cancer (that is Stage I, Stage II or Stage I and II together).
[0028] More specifically, predictive tests and associated methods and products also provide useful clinical information regarding the stage of ovarian cancer progression, that is: Stage I, Stage II, Stage III and Stage IV and an advanced stage which reflects relatively advanced tumors that cannot readily be classified as either Stage III or Stage IV. Overall, the invention also relates to newly discovered correlations between the relative levels of expression of certain groups of markers in bodily fluids, preferably blood serum and plasma, and a subject's ovarian cancer status.
[0029] In one embodiment, the invention provides a set of reagents to measure the expression levels of a panel or set of biomarkers in a fluid sample drawn from a patient, such as blood, serum, plasma, lymph, cerebrospinal fluid, ascites or urine. The reagents in a further embodiment are a multianalyte panel assay comprising reagents to evaluate the expression levels of these biomarker panels.
[0030] In embodiments of the invention, a subject's sample is prepared from tissue samples such a tissue biopsy or from primary cell cultures or culture fluid. In a further embodiment, the expression of the biomarkers is determined at the polypeptide level. Related embodiments utilize immunoassays, enzyme-linked immunosorbent assays and multiplexed immunoassays for this purpose.
[0031] Preferred panels of biomarkers are selected from the group consisting of the following sets of molecules and their measurable fragments: (a) myoglobin, CRP (C reactive protein), FGF basic protein and CA 19-9; (b) Hepatitis C NS4, Ribosomal P Antibody and CRP; (c) CA 19-9, TGF alpha, EN-RAGE, EGF and HSP 90 alpha antibody, (d) EN-RAGE, EGF, CA 125, Fibrinogen, Apolipoprotein CIII, EGF, Cholera Toxin and CA 19-9; (e) Proteinase 3 (cANCA) antibody, Fibrinogen, CA 125, EGF, CD40, TSH, Leptin, CA 19-9 and lymphotactin; (f) CA125, EGFR, CRP, IL-18, Apolipoprotein CIII, Tenascin C and Apolipoprotein A1; (g) CA125, Beta-2 Microglobulin, CRP, Ferritin, TIMP-1, Creatine Kinase-MB and IL-8; (h) CA125, EGFR, IL-10, Haptoglobin, CRP, Insulin, TIMP-1, Ferritin, Alpha-2 Macroglobulin, Leptin, IL-8, CTGF, EN-RAGE, Lymphotactin, TNF-alpha, IGF-1, TNF RII, von Willebrand Factor and MDC; (i) CA-125, CRP, EGF-R, CA-19-9, Apo-AI, Apo-CIII, IL-6, IL-18, MIP-1a, Tenascin C and Myoglobin; (j) CA-125, CRP, EGF-R, CA-19-9, Apo-AI, Apo-CIII, IL-6, MIP-1a, Tenascin C and Myoglobin; and (k) any of the biomarker panels presented in Table II and Table III.
[0032] In another embodiment, the reagents that measure such biomarkers may measure other molecular species that are found upstream or downstream in a biochemical pathway or measure fragments of such biomarkers and molecular species. In some instances, the same reagent may accurately measure a biomarker and its fragments.
[0033] Another embodiment of the present invention relates to binding molecules (or binding reagents) to measure the biomarkers and related molecules and fragments. Contemplated binding molecules includes antibodies, both monoclonal and polyclonal, aptamers and the like.
[0034] Other embodiments include such binding reagents provided in the form of a test kit, optionally together with written instructions for performing an evaluation of biomarkers to predict the likelihood of ovarian cancer in a subject.
[0035] In other of its embodiments, the present invention provides methods of predicting the likelihood of ovarian cancer in a subject based on detecting or measuring the levels in a specimen or biological sample from the subject of the foregoing biomarkers. As described in this specification, a change in the expression levels of these biomarkers, particularly their relative expression levels, as compared with a control group of patients who do not have ovarian cancer, is predictive of ovarian cancer in that subject.
[0036] In other of its aspects, the type of ovarian cancer that is predicted is serous, endometrioid, mucinous, and clear cell tumors. And prediction of ovarian cancer includes the prediction of a specific stage of the disease such as Stage I (IA, IB or IC), II, III and IV tumors.
[0037] In yet another embodiment, the invention relates to creating a report for a physician of the relative levels of the biomarkers and to transmitting such a report by mail, fax, email or otherwise. In an embodiment, a data stream is transmitted via the internet that contains the reports of the biomarker evaluations. In a further embodiment, the report includes the prediction as to the presence or absence of ovarian cancer in the subject or the stratified risk of ovarian cancer for the subject, optionally by subtype or stage of cancer.
[0038] According to another aspect of the invention, the foregoing evaluation of biomarker expression levels is combined for diagnostic purposes with other diagnostic procedures such as gastrointestinal tract evaluation, chest x-ray, HE4 test, CA-125 test, complete blood count, ultrasound or abdominal/pelvic computerized tomography, blood chemistry profile and liver function tests.
[0039] Yet other embodiments of the invention relate to the evaluation of samples drawn from a subject who is symptomatic for ovarian cancer or is at high risk for ovarian cancer. Other embodiments relate to subjects who are asymptomatic of ovarian cancer. Symptomatic subjects have one or more of the following: pelvic mass; ascites; abdominal distention; general abdominal discomfort and/or pain (gas, indigestion, pressure, swelling, bloating, cramps); nausea, diarrhea, constipation, or frequent urination; loss of appetite; feeling of fullness even after a light meal; weight gain or loss with no known reason; and abnormal bleeding from the vagina. The levels of biomarkers may be combined with the findings of such symptoms for a diagnosis of ovarian cancer.
[0040] Embodiments of the invention are highly accurate for determining the presence of ovarian cancer. By “highly accurate” is meant a sensitivity and a specificity each at least about 85 percent or higher, more preferably at least about 90 percent or 92 percent and most preferably at least about 95 percent or 97 percent accurate. Embodiments of the invention further include methods having a sensitivity of at least about 85 percent, 90 percent or 95 percent and a specificity of at least about 55 percent, 65 percent, 75 percent, 85 percent or 90 percent or higher. Other embodiments include methods having a specificity of at least about 85 percent, 90 percent or 95 percent, and a sensitivity of at least about 55 percent, 65 percent, 75 percent, 85 percent or 90 percent or higher.
[0041] Embodiments of the invention relating sensitivity and specificity are determined for a population of subjects who are symptomatic for ovarian cancer and have ovarian cancer as compared with a control group of subjects who are symptomatic for ovarian cancer but who do not have ovarian cancer. In another embodiment, sensitivity and specificity are determined for a population of subjects who are at increased risk for ovarian cancer and have ovarian cancer as compared with a control group of subjects who are at increased risk for ovarian cancer but who do not have ovarian cancer. And in another embodiment, sensitivity and specificity are determined for a population of subjects who are symptomatic for ovarian cancer and have ovarian cancer as compared with a control group of subjects who are not symptomatic for ovarian cancer but who do not have ovarian cancer.
[0042] In other aspects, the levels of the biomarkers are evaluated by applying a statistical method such as knowledge discovery engine (KDE™), regression analysis, discriminant analysis, classification tree analysis, random forests, ProteomeQuest®, support vector machine, One R, kNN and heuristic naive Bayes analysis, neural nets and variants thereof.
[0043] In another embodiment, a predictive or diagnostic model based on the expression levels of the biomarkers is provided. The model may be in the form of software code, computer readable format or in the form of written instructions for evaluating the relative expression of the biomarkers.
[0044] A patient's physician can utilize a report of the biomarker evaluation, in a broader diagnostic context, in order to develop a relatively more complete assessment of the risk that a given patient has ovarian cancer. In making this assessment, a physician will consider the clinical presentation of a patient, which includes symptoms such as a suspicious pelvic mass and/or ascites, abdominal distention and other symptoms without another obvious source of malignancy. The general lab workup for symptomatic patients currently includes a GI evaluation if clinically indicated, chest x-ray, CA-125 test, CBC, ultrasound or abdominal/pelvic CT if clinically indicated, chemistry profile with LFTs and may include a family history evaluation along with genetic marker tests such as BRCA-1 and BRCA-2. (See, generally, the NCCN Clinical Practice Guidelines in Oncology™ for Ovarian Cancer, V.1.2007.)
[0045] The present invention provides a novel and important additional source of information to assist a physician in stratifying a patient's risk of having ovarian cancer and in planning the next diagnostic steps to take. The present invention is also similarly useful in assessing the risk of ovarian cancer in non-symptomatic, high-risk subjects as well as for the general population as a screening tool. It is contemplated that the methods of the present invention may be used by clinicians as part of an overall assessment of other predictive and diagnostic indicators.
[0046] The present invention also provides methods to assess the therapeutic efficacy of existing and candidate chemotherapeutic agents and other types of cancer treatments. As will be appreciated by persons skilled in the art, the relative expression levels of the biomarker panels—or biomarker profiles—are determined as described above, in specimens taken from a subject prior to and again after treatment or, optionally, at progressive stages during treatment. A change in the relative expression of these biomarkers to a non-cancer profile of expression levels (or to a more nearly non-cancer expression profile) or to a stable, non-changing profile of relative biomarker expression levels is interpreted as therapeutic efficacy. Persons skilled in the art will readily understand that a profile of such expressions levels may become diagnostic for cancer or a pre-cancer, pre-malignant condition or simply move toward such a diagnostic profile as the relative ratios of the biomarkers become more like a cancer-related profile than previously.
[0047] In another embodiment, the invention provides a method for determining whether a subject potentially is developing cancer. The relative levels of expression of the biomarkers are determined in specimens taken from a subject over time, whereby a change in the biomarker expression profile toward a cancer profile is interpreted as a progression toward developing cancer.
[0048] The expression levels of the biomarkers of a specimen may be stored electronically once a subject's analysis is completed and recalled for such comparison purposes at a future time.
[0049] The present invention further provides methods, software products, computer systems and networks, and associated instruments that provide a highly accurate test for ovarian cancer.
[0050] The combinations of markers described in this specification provide sensitive, specific and accurate methods for predicting the presence of or detecting ovarian cancer at various stages of its progression. The evaluation of samples as described may also correlate with the presence of a pre-malignant or a pre-clinical condition in a patient. Thus, it is contemplated that the disclosed methods are useful for predicting or detecting the presence of ovarian cancer in a sample, the absence of ovarian cancer in a sample drawn from a subject, the stage of an ovarian cancer, the grade of an ovarian cancer, the benign or malignant nature of an ovarian cancer, the metastatic potential of an ovarian cancer, the histological type of neoplasm associated with the ovarian cancer, the indolence or aggressiveness of the cancer, and other characteristics of ovarian cancer that are relevant to prevention, diagnosis, characterization, and therapy of ovarian cancer in a patient.
[0051] It is further contemplated that the methods disclosed are also useful for assessing the efficacy of one or more test agents for inhibiting ovarian cancer, assessing the efficacy of a therapy for ovarian cancer, monitoring the progression of ovarian cancer, selecting an agent or therapy for inhibiting ovarian cancer, monitoring the treatment of a patient afflicted with ovarian cancer, monitoring the inhibition of ovarian cancer in a patient, and assessing the carcinogenic potential of a test compound by evaluating biomarkers of test animals following exposure.
DETAILED DESCRIPTION
[0052] The biomarker panels and associated methods and products were identified through the analysis of analyte levels of various molecular species in human blood serum drawn from subjects having ovarian cancer of various stages and subtypes, subjects having non-cancer gynecological disorders and normal subjects. The immunoassays described below were courteously performed by our colleagues at Rules-Based Medicine of Austin, Tex. using their Multi-Analyte Profile (MAP) Luminex® platform (www.rulesbasedmedicine.com).
[0053] While a preferred sample is blood serum, it is contemplated that an appropriate sample can be derived from any biological source or sample, such as tissues, extracts, cell cultures, including cells (for example, tumor cells), cell lysates, and physiological fluids, such as, for example, whole blood, plasma, serum, saliva, ductal lavage, ocular lens fluid, cerebral spinal fluid, sweat, urine, milk, ascites fluid, synovial fluid, peritoneal fluid and the like. The sample can be obtained from animals, preferably mammals, more preferably primates, and most preferably humans using species specific binding agents that are equivalent to those discussed below in the context of human sample analysis. It is further contemplated that these techniques and marker panels may be used to evaluate drug therapy in rodents and other animals, including transgenic animals, relevant to the development of human and veterinary therapeutics.
[0054] The sample can be treated prior to use by conventional techniques, such as preparing plasma from blood, diluting viscous fluids, and the like. Methods of sample treatment can involve filtration, distillation, extraction, concentration, inactivation of interfering components, addition of chaotropes, the addition of reagents, and the like. Nucleic acids (including silencer, regulatory and interfering RNA) may be isolated and their levels of expression for the analytes described below also used in the methods of the invention.
Samples and Analytical Platform.
[0055] The set of blood serum samples that was analyzed to generate most of the data discussed below contained 150 ovarian cancer samples and 150 non-ovarian cancer samples. Subsets of these samples were used as described. The ovarian cancer sample samples further comprised the following epithelial ovarian cancer subtypes: serous (64), clear cell (22), endometrioid (35), mucinous (15), mixed, that is, consisting of more than one subtype (14). The stage distribution of the ovarian cancer samples was: Stage I (41), Stage II (23), Stage III (68), Stage IV (12) and unknown stage (6).
[0056] The non-ovarian cancer sample set includes the following ovarian conditions: benign (104), normal ovary (29) and “low malignant potential/borderline (3). The sample set also includes serum from patients with other cancers: cervical cancer (7), endometrial cancer (6) and uterine cancer (1).
[0057] Analyte levels in the samples discussed in this specification were measured using a high-throughput, multi-analyte immunoassay platform. A preferred platform is the Luminex® MAP system as developed by Rules-Based Medicine, Inc. in Austin, Tex. It is described on the company's website and also, for example, in publications such as Chandler et al., “Methods and kits for the diagnosis of acute coronary syndrome, U.S. Patent Application 2007/0003981, published Jan. 4, 2007, and a related application of Spain et al., “Universal Shotgun Assay,” U.S. Patent Application 2005/0221363, published Oct. 6, 2005. This platform has previously been described in Lokshin (2007) and generated data used in other analyses of ovarian cancer biomarkers. However, any immunoassay platform or system may be used.
[0058] In brief, to describe a preferred analyte measurement system, the MAP platform incorporates polystyrene microspheres that are dyed internally with two spectrally distinct fluorochromes. By using accurate ratios of the fluorochromes, an array is created consisting of 100 different microsphere sets with specific spectral addresses. Each microsphere set can display a different surface reactant. Because microsphere sets can be distinguished by their spectral addresses, they can be combined, allowing up to 100 different analytes to be measured simultaneously in a single reaction vessel. A third fluorochrome coupled to a reporter molecule quantifies the biomolecular interaction that has occurred at the microsphere surface. Microspheres are interrogated individually in a rapidly flowing fluid stream as they pass by two separate lasers in the Luminex® analyzer. High-speed digital signal processing classifies the microsphere based on its spectral address and quantifies the reaction on the surface in a few seconds per sample.
[0059] Skilled artisans will recognize that a wide variety of analytical techniques may be used to determine the levels of biomarkers in a sample as is described and claimed in this specification. Other types of binding reagents available to persons skilled in the art may be utilized to measure the levels of the indicated analytes in a sample. For example, a variety of binding agents or binding reagents appropriate to evaluate the levels of a given analyte may readily be identified in the scientific literature. Generally, an appropriate binding agent will bind specifically to an analyte, in other words, it reacts at a detectable level with the analyte but does not react detectably (or reacts with limited cross-reactivity) with other or unrelated analytes. It is contemplated that appropriate binding agents include polyclonal and monoclonal antibodies, aptamers, RNA molecules and the like. Spectrometric methods also may be used to measure the levels of analytes, including immunofluorescence, mass spectrometry, nuclear magnetic resonance and optical spectrometric methods. Depending on the binding agent to be utilized, the samples may be processed, for example, by dilution, purification, denaturation, digestion, fragmentation and the like before analysis as would be known to persons skilled in the art. Also, gene expression, for example, in a tumor cell or lymphocyte also may be determined.
[0060] It is also contemplated that the identified biomarkers may have multiple epitopes for immunassays and/or binding sites for other types of binding agents. Thus, it is contemplated that peptide fragments or other epitopes of the identified biomarkers, isoforms of specific proteins and even compounds upstream or downstream in a biological pathway or that have been post-translationally modified may be substituted for the identified analytes or biomarkers so long as the relevant and relative stoichiometries are taken into account appropriately. Skilled artisans will recognize that alternative antibodies and binding agents can be used to determine the levels of any particular analyte, so long as their various specificities and binding affinities are factored into the analysis.
[0061] A variety of algorithms may be used to measure or determine the levels of expression of the analytes or biomarkers used in the methods and test kits of the present invention. It is generally contemplated that such algorithms will be capable of measuring analyte levels beyond the measurement of simple cut-off values. Thus, it is contemplated that the results of such algorithms will generically be classified as multivariate index analyses by the U.S. Food and Drug Administration. Specific types of algorithms include: knowledge discovery engine (KDE™), regression analysis, discriminant analysis, classification tree analysis, random forests, ProteomeQuest®, support vector machine, One R, kNN and heuristic naive Bayes analysis, neural nets and variants thereof.
ANALYSIS AND EXAMPLES
[0062] The following discussion and examples are provided to describe and illustrate the present invention. As such, they should not be construed to limit the scope of the invention. Those skilled in the art will well appreciate that many other embodiments also fall within the scope of the invention, as it is described in this specification and the claims.
Analysis of Data to Find Informative Biomarker Panels Using the KDE™.
[0063] Correlogic has described the use of evolutionary and pattern recognition algorithms in evaluating complex data sets, including the Knowledge Discovery Engine (KDE™) and ProteomeQuest®. See, for example, Hitt et al., U.S. Pat. No. 6,925,389, “Process for Discriminating Between Biological States Based on Hidden Patterns From Biological Data” (issued Aug. 2, 2005); Hitt, U.S. Pat. No. 7,096,206, “Heuristic Method of Classification,” (issued Aug. 22, 2006) and Hitt, U.S. Pat. No. 7,240,038, “Heuristic Method of Classification,” (to be issued Jul. 3, 2007). The use of this technology to evaluate mass spectral data derived from ovarian cancer samples is further elucidated in Hitt et al., “Multiple high-resolution serum proteomic features for ovarian cancer detection,” U.S. Published Patent Application 2006/0064253, published Mar. 23, 2006.
[0064] When analyzing the data set by Correlogic's Knowledge Discovery Engine, the following five-biomarker panels were found to provide sensitivities and specificities for various stages of ovarian cancer as set forth in Table I. Specifically, KDE Model 1 [2 — 0008 — 20] returned a relatively high accuracy for Stage I ovarian cancer and included these markers: Cancer Antigen 19-9 (CA19-9, Swiss-Prot Accession Number: Q9BXJ9), C Reactive Protein (CRP, Swiss-Prot Accession Number: P02741), Fibroblast Growth Factor-basic Protein (FGF-basic, Swiss-Prot Accession Number: P09038) and Myoglobin (Swiss-Prot Accession Number: P02144). KDE Model 2 [4 — 0002-10] returned a relatively high accuracy for Stage III, IV and “advanced” ovarian cancer and included these markers: Hepatitis C NS4 Antibody (Hep C NS4 Ab), Ribosomal P Antibody and CRP. KDE Model 3 [4 — 0009 — 140] returned a relatively high accuracy for Stage I and included these markers: CA 19-9, TGF alpha, EN-RAGE (Swiss-Prot Accession Number: P80511), Epidermal Growth Factor (EGF, Swiss-Prot Accession Number: P01133) and HSP 90 alpha antibody. KDE Model 4 [4 — 0026 — 100] returned a relatively high accuracy for Stage II and Stages III, IV and “advanced” ovarian cancers and included these markers: EN-RAGE, EGF, Cancer Antigen 125 (CA125, Swiss-Prot Accession Number: Q14596), Fibrinogen (Swiss-Prot Accession Number: Alpha chain P02671; Beta chain P02675; Gamma chain P02679), Apolipoprotein CIII (ApoCIII, Swiss-Prot Accession Number: P02656), Cholera Toxin and CA 19-9. KDE Model 5 [4 — 0027 — 20] also returned a relatively high accuracy for Stage II and Stages III, IV and “advanced” ovarian cancers and included these markers: Proteinase 3 (cANCA) antibody, Fibrinogen, CA 125, EGF, CD40 (Swiss-Prot Accession Number: Q6P2H9), Thyroid Stimulating Hormone (TSH, Swiss-Prot Accession Number: Alpha P01215; Beta P01222 P02679, Leptin (Swiss-Prot Accession Number: P41159), CA 19-9 and Lymphotactin (Swiss-Prot Accession Number: P47992). It is contemplated that skilled artisans could use the KDE analytical tools to identify other, potentially useful sets of biomarkers for predictive or diagnostic value based on the levels of selected analytes. Note that the KDE algorithm may select and utilize various markers based on their relative abundances; and that a given marker, for example the level of cholera toxin in Model IV may be zero but is relevant in combination with the other markers selected in a particular grouping.
[0065] Skilled artisans will recognize that a limited size data set as was used in this specification may lead to different results, for example, different panels of markers and varying accuracies when comparing the relative performance of KDE with other analytical techniques to identify informative panels of biomarkers. These particular KDE models were built on a relatively small data set using 40 stage I ovarian cancers and 40 normal/benigns and were tested blindly on the balance of the stage II, III/IV described above. Thus, the specificity is of the stage I samples reflects sample set size and potential overfitting. The drop in specificity for the balance of the non-ovarian cancer samples also is expected given the relatively larger size of the testing set relative to the training set. Overall, the biomarker panel developed for the stage I samples also provides potentially useful predictive and diagnostic assays for later stages of ovarian cancer given the high sensitivity values.
[0066] However, these examples of biomarker panels illustrate that there are a number of parameters that can be adjusted to impact model performance. For instance in these cases a variety of different numbers of features are combined together, a variety of match values are used, a variety of different lengths of evolution of the genetic algorithm are used and models differing in the number of nodes are generated. By routine experimentation apparent to one skilled in the art, combinations of these parameters can be used to generate other predictive models based on biomarker panels having clinically relevant performance.
[0000]
TABLE I
Results of Analysis Using Knowledge Discovery Engine to develop a stage
I specific classification model.
Sensitivity
Specificity
Accuracy
Sensitivity
Sensitivity
Model Name
Feature
Match
Generation
Node
Stage I
Stage I
Stage I
Stage II
Stage III-IV
Specificity
2_0008_20
4
0.9
20
12
75
100
87.5
60.9
46.5
82.6
4_0002_10
3
0.7
10
4
75
100
87.5
69.6
82.6
56
4_0009_140
5
0.6
140
5
75
100
87.5
43.5
39.5
71.6
4_0026_100
9
0.7
100
5
87.5
100
93.8
78.3
84.9
67
4_0027_20
9
0.8
20
5
87.5
100
93.8
78.3
84.9
60.6
Methods and Analysis to Find Informative Biomarker Panels Using Random Forests.
[0067] A preferred analytical technique, known to skilled artisans, is that of Breiman, Random Forests. Machine Learning, 2001. 45:5-32; as further described by Segel, Machine Learning Benchmarks and Random Forest Regression, 2004; and Robnik-Sikonja, Improving Random Forests, in Machine Learning, ECML, 2004 Proceedings, J.F.B.e. al., Editor, 2004, Springer: Berlin. Other variants of Random Forests are also useful and contemplated for the methods of the present invention, for example, Regression Forests, Survival Forests, and weighted population Random Forests.
[0068] A modeling set of samples was used as described above for diagnostic models built with the KDE algorithm. Since each of the analyte assays is an independent measurement of a variable, under some circumstances, known to those skilled in the art, it is appropriate to scale the data to adjust for the differing variances of each assay. In such cases, biweight, MAD or equivalent scaling would be appropriate, although in some cases, scaling would not be expected to have a significant impact. A bootstrap layer on top of the Random Forests was used in obtaining the results discussed below.
[0069] In preferred embodiments of the present invention, contemplated panels of biomarkers are:
[0070] a. Cancer Antigen 125 (CA125, Swiss-Prot Accession Number: Q14596) and Epidermal Growth Factor Receptor (EGF-R, Swiss-Prot Accession Number: P00533).
[0071] b. CA125 and C Reactive Protein (CRP, Swiss-Prot Accession Number: P02741).
[0072] c. CA 125, CRP and EGF-R.
[0073] d. Any one or more of CA125, CRP and EGF-R, plus any one or more of Ferritin (Swiss-Prot Accession Number: Heavy chain P02794; Light chain P02792), Interleukin-8 (IL-8, Swiss-Prot Accession Number: P10145), and Tissue Inhibitor of Metalloproteinases 1 (TIMP-1, Swiss-Prot Accession Number: P01033),
[0074] e. Any one of the biomarker panels presented in Table II and Table III.
[0075] f. Any of the foregoing panels of biomarkers (a-e) plus any one or more of the other biomarkers in the following list if not previously included in the foregoing panels (a-e). These additional biomarkers were identified empirically or by a literature review: Alpha-2 Macroglobulin (A2M, Swiss-Prot Accession Number: P01023), Apolipoprotein A1-1 (ApoA1, Swiss-Prot Accession Number: P02647), Apolipoprotein C-III (ApoCIII, Swiss-Prot Accession Number: P02656), Apolipoprotein H (ApoH, Swiss-Prot Accession Number: P02749), Beta-2 Microglobulin (B2M, Swiss-Prot Accession Number: P23560), Betacellulin (Swiss-Prot Accession Number: P35070), C Reactive Protein (CRP, Swiss-Prot Accession Number: P02741). Cancer Antigen 19-9 (CA19-9, Swiss-Prot Accession Number: Q9BXJ9), Cancer Antigen 125 (CA125, Swiss-Prot Accession Number: Q14596), Collagen Type 2 Antibody, Creatine Kinase-MB (CK-MB, Swiss-Prot Accession Number: Brain P12277; Muscle P06732), C Reactive Protein (CRP, Swiss-Prot Accession Number: P02741), Connective Tissue Growth Factor (CTGF, Swiss-Prot Accession Number: P29279), Double Stranded DNA Antibody (dsDNA Ab), EN-RAGE (Swiss-Prot Accession Number: P80511), Eotaxin (C-C motif chemokine 11, small-inducible cytokine A11 and Eosinophil chemotactic protein, Swiss-Prot Accession Number: P51671), Epidermal Growth Factor Receptor (EGF-R, Swiss-Prot Accession Number: P00533), Ferritin (Swiss-Prot Accession Number: Heavy chain P02794; Light chain P02792), Follicle-stimulating hormone (FSH, Follicle-stimulating hormone beta subunit, FSH-beta, FSH-B, Follitropin beta chain, Follitropin subunit beta, Swiss-Prot Accession Number: P01225), Haptoglobin (Swiss-Prot Accession Number: P00738), HE4 (Major epididymis-specific protein E4, Epididymal secretory protein E4, Putative protease inhibitor WAP5 and WAP four-disulfide core domain protein 2, Swiss-Prot Accession Number: Q14508), Insulin (Swiss-Prot Accession Number: P01308), Insulin-like Growth Factor 1 (IGF-1, Swiss-Prot Accession Number: P01343), Insulin like growth factor II (IGF-II, Somatomedin-A, Swiss-Prot Accession Number: P01344), Insulin Factor VII (Swiss-Prot Accession Number: P08709), Interleukin-6 (IL-6, Swiss-Prot Accession Number: P05231), Interleukin-8 (IL-8, Swiss-Prot Accession Number: P10145), Interleukin-10 (IL-10, Swiss-Prot Accession Number: P22301), Interleukin-18 (IL-18, Swiss-Prot Accession Number: Q14116), Leptin (Swiss-Prot Accession Number: P41159), Lymphotactin (Swiss-Prot Accession Number: P47992), Macrophage-derived Chemokine (MDC, Swiss-Prot Accession Number: 000626), Macrophage Inhibotory Factor (SWISS PROT), Macrophage Inflammatory Protein 1 alpha (MIP-1alpha, Swiss-Prot Accession Number: P10147), Macrophage migration inhibitory factor (MIF, Phenylpyruvate tautomerase, Glycosylation-inhibiting factor, GIF, Swiss-Prot Accession Number: P14174), Myoglobin (Swiss-Prot Accession Number: P02144), Ostopontin (Bone sialoprotein 1, Secreted phosphoprotein 1, SPP-1, Urinary stone protein, Nephropontin, Uropontin, Swiss-Prot Accession Number: P10451), Pancreatic Islet Cells (GAD) Antibody, Prolactin (Swiss-Prot Accession Number: P01236), Stem Cell Factor (SCF, Swiss-Prot Accession Number: P21583), Tenascin C (Swiss-Prot Accession Number: P24821), Tissue Inhibitor of Metalloproteinases 1 (TIMP-1, Swiss-Prot Accession Number: P01033), Tumor Necrosis Factor-alpha (TNF-alpha, Swiss-Prot Accession Number: P01375), Tumor Necrosis Factor RII (TNF-RII, Swiss-Prot Accession Number: Q92956), von Willebrand Factor (vWF, Swiss-Prot Accession Number: P04275) and the other biomarkers identified as being informative for cancer in the references cited in this specification.
[0076] Using the Random Forests analytical approach, a preferred seven biomarker panel was identified that has a high predictive value for Stage I ovarian cancer. It includes: ApoA1, ApoCI1, CA125, CRP, EGF-R, IL-18 and Tenascin. In the course of building and selecting the relatively more accurate models for Stage I cancers generated by Random Forests using these biomarkers, the sensitivity for Stage I ovarian cancers ranged from about 80% to about 85%. Sensitivity was also about 95 for Stage II and about 94% sensitive for Stage III/IV. The overall specificity was about 70%.
[0077] Similarly, a preferred seven biomarker panel was identified that has a high predictive value for Stage II. It includes: B2M, CA125, CK-MB, CRP, Ferritin, IL-8 and TIMPI. A preferred model for Stage II had a sensitivity of about 82% and a specificity of about 88%.
[0078] For Stage III, Stage IV and advanced ovarian cancer, the following 19 biomarker panel was identified: A2M, CA125, CRP, CTGF, EGF-R, EN-RAGE, Ferritin, Haptoglobin, IGF-1, IL-8, IL-10, Insulin, Leptin, Lymphotactin, MDC, TIMP-1, TNF-alpha, TNF-RII, vWF. A preferred model for Stage III/IV had a sensitivity of about 86% and a specificity of about 89
[0079] Other preferred biomarker or analyte panels for detecting, diagnosing and monitoring ovarian cancer are shown in Table II and in Table III. These panels include CA-125, CRP and EGF-R and, in most cases, CA19-9. In Table II, 20 such panels of seven analytes each selected from 20 preferred analytes are displayed in columns numbered 1 through 20. In Table III, another 20 such panels of seven analytes each selected from 23 preferred analytes are displayed in columns numbered 1 through 20.
[0000]
TABLE II
Additional Biomarker Panels
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
CA125
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
CRP
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
EGF-R
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
CA19-9
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
Haptoglobin
Serum Amyloid P
x
x
x
Apo A1
x
x
IL-6
x
x
x
x
x
x
Myoglobin
x
x
x
x
x
x
x
x
x
x
x
MIP-1□
x
x
x
x
x
x
x
x
x
x
x
x
EN-RAGE
CK-MB
vWF
x
x
x
Leptin
x
x
Apo CIII
x
x
x
Growth Hormone
x
x
x
x
x
x
IL-10
IL-18
x
x
x
x
x
x
x
x
Myeloperoxidase
x
x
VCAM-1
x
x
x
[0000]
TABLE III
Additional Biomarker Panels
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
CA125
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
CRP
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
EGF-R
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
CA19-9
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
Haptoglobin
Serum Amyloid P
x
x
x
Apo A1
x
x
IL-6
x
x
x
x
x
x
Myoglobin
x
x
x
x
x
x
x
x
x
x
MIP-1□
x
x
x
x
x
x
x
x
x
x
x
x
x
x
EN-RAGE
CK-MB
x
vWF
x
x
x
x
Leptin
x
x
x
Apo CIII
x
x
x
x
x
x
Growth Hormone
IL-10
x
x
IL-18
Myeloperoxidase
x
x
x
VCAM-1
Insulin
x
Ferritin
x
x
x
x
x
Haptoglobin
x
[0080] Other preferred biomarker panels (or models) for all stages of ovarian cancer include: (a) CA-125, CRP, EGF-R, CA-19-9, Apo-AI, Apo-CIII, IL-6, IL-18, MIP-1a, Tenascin C and Myoglobin; (b) CA125, CRP, CA19-9, EGF-R, Myoglobin, IL-18, Apo CIII; and (c) CA125, CRP, EGF-R, CA19-9, Apo CIII, MIP-1a, Myoglobin, IL-18, IL-6, Apo AI, Tenascin C, vWF, Haptoglobin, IL-10. Optionally, any one or more of the following biomarkers may be added to these or to any of the other biomarker panels disclosed above in text or tables (to the extent that any such panels are not already specifically identified therein): vWF, Haptoglobin, IL-10, IGF-I, IGF-II, Prolactin, HE4, ACE, ASP and Resistin.
[0081] Any two or more of the preferred biomarkers described above will have predictive value, however, adding one or more of the other preferred markers to any of the analytical panels described herein may increase the panel's predictive value for clinical purposes. For example, adding one or more of the different biomarkers listed above or otherwise identified in the references cited in this specification may also increase the biomarker panel's predictive value and are therefore expressly contemplated. Skilled artisans can readily assess the utility of such additional biomarkers. It is contemplated that additional biomarker appropriate for addition to the sets (or panels) of biomarkers disclosed or claimed in this specification will not result in a decrease in either sensitivity or specificity without a corresponding increase in either sensitivity or specificity or without a corresponding increase in robustness of the biomarker panel overall. A sensitivity and/or specificity of at least about 80% or higher are preferred, more preferably at least about 85% or higher, and most preferably at least about 90% or 95% or higher.
[0082] To practice the methods of the present invention, appropriate cut-off levels for each of the biomarker analytes must be determined for cancer samples in comparison with control samples. As discussed above, it is preferred that at least about 40 cancer samples and 40 benign samples (including benign, non-malignant disease and normal subjects) be used for this purpose, preferably case matched by age, sex and gender. Larger sample sets are preferred. A person skilled in the art would measure the level of each biomarker in the selected biomarker panel and then use an algorithm, preferably such as Random Forest, to compare the level of analytes in the cancer samples with the level of analytes in the control samples. In this way, a predictive profile can be prepared based on informative cutoffs for the relevant disease type. The use of a separate validation set of samples is preferred to confirm the cut-off values so determined. Case and control samples can be obtained by obtaining consented (or anonymized) samples in a clinical trial or from repositories like the Screening Study for Prostate, Lung, Colorectal, and Ovarian Cancer—PLCO Trial sponsored by the National Cancer Institute (http://www.cancer.gov/clinicaltrials/PLCO-1) or The Gynecologic Oncology Group (http://www.gog.org/). Samples obtained in multiple sites are also preferred.
[0083] The results of analysis of patients' specimens using the disclosed predictive biomarker panels may be output for the benefit of the user or diagnostician, or may otherwise be displayed on a medium such as, but not limited to, a computer screen, a computer readable medium, a piece of paper, or any other visible medium.
[0084] The foregoing embodiments and advantages of this invention are set forth, in part, in the preceding description and examples and, in part, will be apparent to persons skilled in the art from this description and examples and may be further realized from practicing the invention as disclosed herein. For example, the techniques of the present invention are readily applicable to monitoring the progression of ovarian cancer in an individual, by evaluating a specimen or biological sample as described above and then repeating the evaluation at one or more later points in time, such that a difference in the expression or disregulation of the relevant biomarkers over time is indicative of the progression of the ovarian cancer in that individual or the responsiveness to therapy. All references, patents, journal articles, web pages and other documents identified in this patent application are hereby incorporated by reference in their entireties.
OVARIAN CANCER BIOMARKERS—REFERENCES
[0000]
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Methods are provided for predicting the presence, subtype and stage of ovarian cancer, as well as for assessing the therapeutic efficacy of a cancer treatment and determining whether a subject potentially is developing cancer. Associated test kits, computer and analytical systems as well as software and diagnostic models are also provided.
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CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority of Korean Patent Application No. 2003-5234, filed on 27 Jan. 2003 in the Korean Intellectual Property Office, the disclosure of which is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to the field of electronics, and more particularly, to termination circuits for electronic devices.
BACKGROUND
[0003] Devices having high-speed operating characteristics, operating in response to high clock frequencies, and/or requiring long transmission lines may exhibit undershoot signal reflections and/or undesired transmission line effects.
[0004] If a signal with a “0” voltage level travels down a bus or a long transmission line, the signal may then inverted to a “5” voltage level, and an impedance mismatch between a receiver circuit and the bus or the transmission line may be left uncorrected so that, reflection may occur on the transmission line or at one or both ends of the bus. Because of the reflection, the signal may take a long time to stabilize after the voltage level transition from “0” to “5” volts.
[0005] High-speed semiconductor devices may have reduced clock signal rise and fall times. If the rise and fall times are shorter than 2.5 times a delay in the transmission line of the clock signal, the clock signal received by the receiver circuit may be significantly distorted and may be unusable as a valid signal. Such a problem may be referred to as ringing. In an attempt to reduce distortion and reflection, impedance matching may be implemented for electromagnetic wave transmission.
[0006] [0006]FIG. 1 is a circuit diagram illustrating a known termination circuit. Referring to FIG. 1, termination resistors R 1 and R 2 , a PMOS transistor MP, and an NMOS transistor MN are serially connected between a supply voltage VDD and a ground voltage VSS. The PMOS transistor MP has a gate connected to the ground voltage VSS, and the NMOS transistor MN has a gate connected to the supply voltage VDD. In a termination circuit 100 of FIG. 1, impedance matching is implemented in parallel.
[0007] An impedance of a transmission line (to which an input signal INS is applied) is matched with impedances of the termination resistors R 1 and R 2 . The waveform of a voltage level at the first node N 1 (between the termination resistors R 1 and R 2 ) may show reduced distortion compared to the case when the termination resistors R 1 and R 2 are not connected with the PMOS transistor MP and the NMOS transistor MN.
[0008] In the termination circuit 100 , however, the PMOS transistor MP and the NMOS transistor MN may be turned on all the time, and a path for current flow may be formed from the supply voltage VDD toward the ground voltage VSS. Thus, power consumption increases during transmission of the input signal INS may make it undesirable to use the termination circuit 100 in a low power-consumption device.
[0009] [0009]FIG. 2 is a circuit diagram illustrating another known termination circuit 200 . Referring to FIG. 2, the termination resistors R 1 and R 2 , the PMOS transistor MP, and the NMOS transistor MN are serially connected between the supply voltage VDD and the ground voltage VSS. The PMOS transistor MP has a gate connected to an inverter I 1 that inverts the voltage level of the input signal INS and applies the inverted voltage level to the gate of the PMOS transistor MP. The NMOS transistor MN has a gate connected to an inverter I 2 that inverts the voltage level of the input signal INS and applies the inverted voltage level to the gate of the NMOS transistor MN. In the termination circuit 200 of FIG. 2, impedance matching is implemented in parallel.
[0010] When the inverter I 1 inverts the voltage level of the input signal INS during/after a transition from low to high, the PMOS transistor MP may be turned on. Then, a path for current flow can be formed between the first node N 1 and the supply voltage VDD.
[0011] The voltage level at the first node N 1 can be increased by the supply voltage VDD and may reach the level of the supply voltage VDD or ground voltage VSS. Thus, a relatively long time may be needed to invert the voltage level at the first node N 1 from high to low and vice versa.
[0012] [0012]FIG. 3 is a waveform of the voltage level at the first node N 1 of the termination circuit 200 of FIG. 2. Referring to FIG. 3, when the voltage level of the input signal INS is inverted to a high voltage level, the waveform of the voltage level at the first node N 1 is also inverted a high voltage level. However, when the PMOS transistor MP is turned on, distortion may occur at the first node N 1 , as shown by the waveform in FIG. 3. In other words, the termination circuit 200 of FIG. 2 may provide lower power consumption compared to the termination circuit 100 of FIG. 1, but distortion may occur at the first node N 1 .
[0013] [0013]FIG. 4 is a circuit diagram illustrating still another known termination circuit 400 . Referring to FIG. 4, the PMOS transistor MP, the NMOS transistor MN, and termination resistors R 3 and R 4 are serially connected between the supply voltage VDD and the ground voltage VSS. A first capacitor C 1 is connected between the gate of the PMOS transistor MP and the first node N 1 (which functions as a connection point of the termination resistors R 3 and R 4 ). A resistor R 1 is connected between the supply voltage VDD and the gate of the PMOS transistor MP. A second capacitor C 2 is connected between the gate of the NMOS transistor MN and the first node N 1 , and a resistor R 2 is connected between the ground voltage VSS and the gate of the NMOS transistor MN.
[0014] The PMOS transistor MP and the NMOS transistor MN can be turned off using the first capacitor C 1 and the second capacitor C 2 . If the input signal INS is input at a high voltage level, the second capacitor C 2 may be charged and the NMOS transistor MN may be turned on for a moment, while the PMOS transistor MP is turned off. Electrical charges in the second capacitor C 2 may dissipate through the ground voltage VSS, and then the NMOS transistor MN may be turned off. Thus, termination of the input signal INS may be inaccurately performed.
[0015] [0015]FIG. 5A is a graph showing impedances of the termination transistors R 3 and R 4 of the termination circuit 400 of FIG. 4. FIG. 5B is a waveform of the voltage level at the first node N 1 of FIG. 4.
[0016] Referring to FIG. 5A, the impedances of the termination resistors R 3 and R 4 may be nearly infinite at time points immediately before the signal INS is input and after the NMOS transistor MN is turned on and off by the input signal INS.
[0017] Because the impedances of the termination resistors R 3 and R 4 may have to be maintained level with respect to a specific value to reduce ringing or reflection, however, the termination circuit 400 of FIG. 4 may not accurately perform termination of the input signal INS.
[0018] Referring to FIG. 5B, the waveform of the voltage level at the first node N 1 may exhibit high overshoot and/or undershoot when the voltage level of the input signal INS transitions from low to high and/or from high to low. Known termination circuits may consume high power and/or distort signals.
SUMMARY
[0019] According to embodiments of the present invention, a termination circuit for a transmission line may include an input node, a pull-down circuit, and a pull-up circuit. The input node receives an input signal over the transmission line. The pull-down circuit is coupled between the input node and a first reference voltage, and the pull-down circuit is configured to provide an electrical path between the first reference voltage and the input node responsive to the input signal having a first voltage level. The pull-up circuit is coupled between the input node and a second reference voltage wherein the pull-up circuit is configured to provide an electrical path between the second reference voltage and the input node responsive to the input signal having a second voltage level. More particularly, the first reference voltage is less than the second reference voltage, and the first voltage level is greater than the second voltage level.
[0020] For example, the first voltage level may be a logic high voltage level, and the second voltage level may be a logic low voltage level. Moreover, the first reference voltage may be a ground voltage, and the second reference voltage may be a supply voltage.
[0021] In addition, the pull-down circuit may be further configured to block the electrical path between the first reference voltage and the input node responsive to the input signal having the second voltage level. Similarly, the pull-up circuit may be further configured to block the electrical current path between the second reference voltage and the input node responsive to the input signal having the first voltage level. The pull-down and pull-up circuits may also be configured to provide electrical paths between the input node and both of the first and second reference voltages at a same time during a transition of the input signal between the first and second voltage levels.
[0022] More particularly, the pull-down circuit may include a pull-down resistor and a pull-down transistor coupled in series between the input node and the first reference voltage. The pull-down circuit may also include a first input resistor connected between the input node and a control electrode (such as a gate) of the pull-down transistor. Moreover, the pull-down transistor may be an NMOS transistor.
[0023] The pull-up circuit may include a pull-up resistor and a pull-up transistor coupled in series between the input node and the second reference voltage. The pull-up circuit may also include a pull-up input resistor connected between the input node and a control electrode (such as a gate) of the pull-up transistor. Moreover, the pull-up transistor may be a PMOS transistor.
[0024] According to additional embodiments of the present invention, a method of terminating a transmission line may include receiving an input signal at an input node. An electrical path may be provided between a first reference voltage and the input node responsive to the input signal having a first voltage level. An electrical path may be provided between a second reference voltage and the input node responsive to the input signal having a second voltage level. In addition, the first reference voltage may be less than the second reference voltage, and the first voltage level may be greater than the second voltage level.
[0025] For example, the first voltage level may be a logic high voltage level, and the second voltage level may be a logic low voltage level. In addition, the first reference voltage may be a ground voltage, and the second reference voltage may be a supply voltage.
[0026] In addition, the electrical current path between the first reference voltage and the input node may be blocked responsive to the input signal having the second voltage level. Similarly, the electrical current path between the second reference voltage and the input node may be blocked responsive to the input signal having the first voltage level. In addition, electrical paths may be provided between the input node and both of the first and second reference voltages at a same time during a transition of the input signal between the first and second voltage levels.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The above and other aspects and advantages of the present invention will become more apparent by describing in detail embodiments thereof with reference to the attached drawings in which:
[0028] [0028]FIG. 1 is a circuit diagram illustrating a known termination circuit.
[0029] [0029]FIG. 2 is a circuit diagram illustrating another known termination circuit.
[0030] [0030]FIG. 3 is a waveform of the voltage level at the first node of the known termination circuit of FIG. 2.
[0031] [0031]FIG. 4 is a circuit diagram illustrating still another known termination circuit.
[0032] [0032]FIG. 5A is a graph showing impedances of termination transistors of the termination circuit of FIG. 4.
[0033] [0033]FIG. 5B is a waveform of a voltage level at the first node of the termination circuit of FIG. 4.
[0034] [0034]FIG. 6 is a circuit diagram illustrating a termination circuit according to embodiments of the present invention.
[0035] [0035]FIG. 7A is a graph showing impedances of termination resistors of FIG. 6 according to embodiments of the present invention.
[0036] [0036]FIG. 7B is a waveform of a voltage level at the first node of the termination circuit of FIG. 6.
DETAILED DESCRIPTION
[0037] The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which typical embodiments of the invention are shown. This invention, however, may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. It will also be understood that when an element is referred to as being “coupled” or “connected” to another element, it can be directly coupled or connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly coupled” or “directly connected” to another element, there are no intervening elements present. Like numbers refer to like elements throughout.
[0038] [0038]FIG. 6 is a circuit diagram illustrating a termination circuit according to embodiments of the present invention. Referring to FIG. 6, a termination circuit 600 includes a first switching unit 610 and a second switching unit 620 , and the termination circuit 600 may reduce ringing and dynamic current which may occur when an input signal INS is transmitted through a transmission line. The first switching unit 610 includes a first termination resistor RTER 1 providing a path for current flow between a first node N 1 and a first reference voltage VSS when the voltage level of the input signal INS is inverted to the first level. More specifically, the first switching unit 610 also includes a first transistor MN connected in series with the first termination resistor RTER 1 between the node N 1 and the first reference voltage Vss. The first transistor MN has a first end (source/drain) connected to the first voltage VSS and a gate receiving the input signal INS. The first termination resistor RTER 1 is connected between the second end (source/drain) of the first transistor MN and the first node N 1 .
[0039] The first transistor MN can be an NMOS transistor, the first voltage VSS can be a ground voltage, and the first level can be a high voltage level. The first switching unit 610 may also include a first input resistor R 1 used to protect the gate of the first transistor MN and connected between the first node N 1 and the gate of the first transistor MN.
[0040] The second switching unit 620 includes a second termination resistor RTER 2 providing a path for current flow between the first node N 1 and a second reference voltage VDD when the input signal INS is inverted to the second level. More specifically, the second switching unit 620 also includes the second transistor MP connected in series with the second termination resistor RTER 2 between the node N 1 and the second reference voltage VDD. The second transistor MP has a first end connected to the second voltage VDD and a gate receives the input signal INS. The second termination resistor RTER 2 is connected between a second end of the second transistor MP and the first node N 1 .
[0041] The second transistor MP may be a PMOS transistor, the second reference voltage VDD may be a supply voltage, and the second level may be low. The second switching unit 620 may further include a second resistor R 2 used to protect the gate of the second transistor MP and positioned between the first node N 1 and the gate of the second transistor MP.
[0042] The first and second switching units 610 and 620 may keep termination resistances level (and/or matched) with respect to a resistance of the transmission line when the voltage level of the input signal INS is inverted. The termination circuit 600 may be included in an integrated circuit semiconductor chip.
[0043] Hereinafter, the operation of the termination circuit 600 will be described with reference to FIG. 6. In the termination circuit 600 of FIG. 6, either the first switching unit 610 or the second switching unit 620 may be turned on, and the other is turned off, irrespective of whether the voltage level of the input signal INS is high or low. Thus, the path for current flow is not formed toward the first reference voltage (the ground voltage) VSS from the second voltage (the supply voltage) VDD, which may allow for a reduction in power consumption.
[0044] When the voltage level of the input signal INS is inverted from low to high, the first transistor MN is turned on, and the second transistor MP is turned off. The path for current flow is formed from the first node N 1 toward the first voltage (the ground voltage) VSS having a voltage level opposite to that of the input signal INS, in this case, a low voltage level. Thus, the voltage level at the first node N 1 does not reach the voltage level of the input signal INS, but reaches a voltage level lower than that of the input signal INS.
[0045] In the alternative case, if the voltage level of the input signal INS is inverted from high to low, the second transistor MP is turned on and the first transistor MN is turned off. Then, the path for current flow is formed from the first node N 1 toward the second voltage (the supply voltage) VDD, and the voltage level at the first node N 1 does not reach the voltage level of the input signal INS, but reaches a voltage level slightly higher than that of the input signal INS. Accordingly, an amount of time required for the voltage level at the first node N 1 to be inverted from high to low may be reduced.
[0046] When the voltage level of the input signal INS is inverted, impedances of the first termination resistor RTER 1 and the second termination resistor RTER 2 can be continuously matched with the impedance of the transmission line through which the input signal INS is transmitted. The matching occurs because either the first transistor MN or the second transistor MP has already been turned on due to previously inverting the voltage level of the input signal INS.
[0047] Also, when the voltage level of the input signal INS is inverted, a small amount of time may be required for either the first transistor MN or the second transistor MP to be turned on or off. Thus, both the first transistor MN and the second transistor MP may be turned on for a moment.
[0048] At that moment, since it seems to the input signal INS that the first termination resistor RTER 1 and the second termination resistor RTER 2 are connected in parallel, the impedances of RTER 1 and RTER 2 can be constantly maintained level (and/or matched) with respect to a specific value. The first resistor R 1 and the second resistor R 2 are used to protect the gates of the first transistor MN and the second transistor MP, respectively, from damage by the input signal INS.
[0049] [0049]FIG. 7A is a graph showing the impedances of the first termination resistor RTER 1 and the second termination resistor RTER 2 of the termination circuit 600 of FIG. 6 according to embodiments of the present invention. FIG. 7B is a waveform of the voltage level at the first node N 1 of the termination circuit 600 of FIG. 6.
[0050] Referring to FIG. 7A, the impedances of the first termination resistor RTER 1 and the second termination resistor RTER 2 (indicated by a bold line) may be constantly maintained relatively level with respect to a specific value. The dotted lines indicate the respective impedances of the first termination resistor RTER 1 and the second termination resistor RTER 2 .
[0051] Referring to FIG. 7B, the amount of time required for the voltage level at the first node N 1 to be inverted may be smaller than that required for the voltage level of the input signal INS to be inverted. An amount of time required for the termination circuit 600 to transmit a signal to a circuit (not shown), connected to the termination circuit 600 may be reduced.
[0052] Moreover, since the impedances of the first termination resistor RTER 1 and the second termination resistor RTER 2 are maintained level with respect to a specific value, the waveform of the voltage level at the first node N 1 may exhibit reduced distortion. The termination circuit 600 can be included in an integrated circuit semiconductor chip.
[0053] A termination circuit according to second embodiments of the present invention may include a first termination unit and a second termination unit.
[0054] The first termination unit may include a first termination resistor that allows impedance matching to be performed using a ground voltage when the voltage level of the input signal is inverted from low to high. The second termination unit may include a second termination resistor that allows impedance matching to be performed using a supply voltage when the voltage level of the input signal is inverted from high to low.
[0055] The operation and configuration of the first termination unit may be the same as that of the first switching unit 610 in the first embodiment. The operation and configuration of the second termination unit may be the same as that of the second switching unit 620 in the first embodiments. Accordingly, detailed operations of the termination circuits according to the second embodiments of the present invention will not be described.
[0056] A termination circuit according to third embodiments of the present invention may include a pull-down unit and a pull-up unit. The pull-down unit may prevent the voltage level at the first node from reaching the voltage level of a second voltage when the voltage level of the input signal is inverted to a first level. The pull-up unit may prevent the voltage level at the first node from reaching the voltage level of a first voltage when the voltage level of the input signal is inverted to a second level.
[0057] The pull-down unit may function as and may have the same configuration as the first switching unit 610 of the first embodiments. The pull-up unit may function as and have the same configuration as the second switching unit 620 of the first embodiments. Accordingly, detailed operations of the termination circuit according to third embodiments of the present invention will not be described further herein.
[0058] As described above, termination circuits according to embodiments of the present invention can reduce power consumption, reduce an amount of time required for signal transmission, and may transmit a signal with reduced distortion in an output waveform.
[0059] Embodiments of the present invention may provide termination circuits which reduce power consumption and/or reduce distortion in an output waveform.
[0060] According to some embodiments of the present invention, a termination circuit may reduce ringing and/or dynamic current, which occur when an input signal is transmitted through a transmission line. The termination circuit may include a first switching unit and a second switching unit. The first switching unit includes a first termination resistor used to form a path for current flow between a first node and a first voltage when a voltage level of the input signal is inverted to a first level. The second switching unit includes a second termination resistor used to form a path for current flow between the first node and a second voltage when the voltage level of the input signal is inverted to a second level. Termination resistances of the first and second switching units may be maintained level to a resistance of the transmission line when the voltage level of the input signal is inverted.
[0061] The first switching unit may include a first transistor and a first termination resistor. A first end of the first transistor is connected to the first voltage, and a gate of the first transistor receives the input signal. The first termination resistor is connected between a second end of the first transistor and the first node.
[0062] The first switching unit may further include a first input resistor, used to protect the gate of the first transistor and positioned between the first node and the gate of the first transistor. The first transistor may be an NMOS transistor.
[0063] The second switching unit may include a second transistor and a second termination resistor. The second termination resistor includes a first end connected to the second voltage and a gate receiving the input signal. The second termination resistor is connected between a second end of the second transistor and the first node.
[0064] The second switching unit may also include a second resistor used to protect the gate of the second transistor. The second input transistor is positioned between the first node and the gate of the second transistor. The second transistor may be a PMOS transistor.
[0065] A voltage level of the first voltage may be the same as a voltage level of a ground voltage, and a voltage level of the second voltage may be the same as a voltage level of a supply voltage. The first level may be high and the second level may be low. The termination circuit may be included in an integrated circuit semiconductor chip.
[0066] According to other embodiments of the present invention, a termination circuit may reduce ringing and dynamic current which occur when an input signal is transmitted through a transmission line. The termination circuit may include a first termination unit and a second termination unit. The first termination unit includes a first termination resistor allowing impedance matching to be performed using a ground voltage when a voltage level of the input signal is inverted to high. The second termination unit includes a second termination resistor allowing impedance matching to be performed by using a supply voltage when a voltage level of the input signal is inverted to low. Termination resistance of the first and second termination units may be maintained level with respect to a resistance of the transmission line when the voltage level of the input signal is inverted.
[0067] The first termination unit may also include an NMOS transistor and a first termination resistor. A first end of the first NMOS transistor is connected to the ground voltage and a gate of the first NMOS transistor receives the input signal. The first termination resistor is connected between a second end of the NMOS transistor and a first node.
[0068] The first termination unit may also include a first input resistor used to protect the gate of the NMOS transistor and positioned between the first node and the gate of the NMOS transistor.
[0069] The second termination unit may also include a PMOS transistor and a second termination resistor. A first end of the second termination resistor is connected to the supply voltage and a gate receives the input signal. The second termination resistor is connected between a second end of the PMOS transistor and the first node.
[0070] The second termination unit may also include a second resistor used to protect the gate of the PMOS transistor and positioned between the first node and the gate of the PMOS transistor. The termination circuit may be included in an integrated circuit semiconductor chip.
[0071] According to yet other embodiments of the present invention, a termination circuit may reduce ringing and dynamic current which may occur when an input signal is transmitted through a transmission line. The termination circuit may include a pull-down unit and a pull-up unit. The pull-down unit may prevent a voltage level at a first node from reaching a voltage level of a second voltage when a voltage level of the input signal is inverted to a first level. The pull-up unit may prevent a voltage level at the first node from reaching a voltage level of a first voltage when a voltage level of the input signal is inverted to a second level.
[0072] The pull-down unit may further include an NMOS transistor and a first termination resistor. A first end of the NMOS transistor may be connected to the first voltage and a gate may receive the input signal. The first termination resistor is connected between a second end of the NMOS transistor and the first node. The pull-down unit may further include a first resistor used to protect the gate of the NMOS transistor, between the first node and the gate of the NMOS transistor.
[0073] The pull-up unit may further include a PMOS transistor and a second termination resistor. A first end of the PMOS transistor may be connected to the second voltage and a gate connected to receive the input signal. The second termination resistor is connected between a second end of the PMOS transistor and the first node.
[0074] The pull-up unit may further include a second resistor used to protect the gate of the PMOS transistor, between the first node and the gate of the PMOS transistor. A voltage level of the first voltage may be the same as a voltage level of a ground voltage, and a voltage level of the second voltage may be the same as a voltage level of a supply voltage. The first level may be high, and the second level may be low. The termination circuit may be included in an integrated circuit semiconductor chip.
[0075] While the present invention has been particularly shown and described with reference to embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents.
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A termination circuit for a transmission line may include an input node, a pull-down circuit, and a pull-up circuit. The input node receives an input signal over the transmission line. The pull-down circuit is coupled between the input node and a first reference voltage, and the pull-down circuit may be configured to provide an electrical path between the first reference voltage and the input node responsive to the input signal having a first voltage level. The pull-up circuit is coupled between the input node and a second reference voltage, and the pull-up circuit is configured to provide an electrical path between the second reference voltage and the input node responsive to the input signal having a second voltage level. More particularly, the first reference voltage is less than the second reference voltage, and the first voltage level is greater than the second voltage level. Related methods are also discussed.
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FIELD OF THE INVENTION
The invention relates to a valve for a cooking utensil or the like, for example a pressure cooker, which is operated with excess pressure and can be closed off with a lid, including a valve member, which is arranged in a valve opening provided in the lid, axially aligned and movably within said valve opening, and indicates, controls and monitors the various operating stages of the cooking utensil.
BACKGROUND OF THE INVENTION
It has been known for a long time to arrange an indicating pin in a pressure cooker, which pin is axially adjustable by the pressure existing in the cooking utensil against a restoring force. The indicating pin can be moved in a passage in the utensil wall of the cooking utensil, in particular in the lid, in such a manner that it is driven out of the cooking utensil by an increasing pressure so that the length of the indicating pin above the utensil wall indicates the pressure in the cooking utensil. Valves with such an indicating pin have been used extensively for a long time. Usually several annular grooves, which are associated, if necessary, with several differing restoring forces and are usually colored, and which are used for observing the pressure, are provided on the indicating pin. Such a valve consists thereby of several metallic individual parts and associated rubber-elastic sealing elements. Even though the metal parts, but for the restoring spring, are turned parts manufactured by cutting, for example on a lathe and if desired on automated machines, the expense for the manufacture and the assembly of such a valve is significant. The metal parts must be physiologically unobjectionable for use with cooking utensils and must consist of a suitable, at least surface-treated material, such that the cost of manufacturing the valve is further increased,
These valves serve, aside the purpose of indicating the pressure inside of the cooking utensil, also as a control for the cooking utensil by ventilating during the cooking process when the pressure is too high and thus regulating a maximum pressure within the utensil. Such a ventilation is also desired at the start of the operation of the cooking utensil in order to replace the air above the food with steam, and when the operating pressure of the cooking utensil is just about reached, the flow connection of the inside with the outside must then be interrupted. The indicating pin can be moved manually into a position, in which the inside of the cooking utensil can be ventilated and can become pressureless so that the lid can be removed without any significant risk to the user.
The conventional valves are difficult to clean and to service. They must for this purpose be at least disassembled into their individual parts requiring suitable tools and skill of a craftsman.
It therefore has also already been suggested according to the Gebrauchsmuster (German Utility Model Document) 295 01 112.2 to design such a valve substantially simpler in such a manner that it consists aside from the indicating pin for the pressure level only one single structural element, which is manufactured of a rubber-elastic material and can also perform a plurality of functions. Aside from the indicating pin, the valve consists thereby, in the most favorable case, only of one single holding piece, the elasticity of which is sufficient in order to be able to fasten it in the utensil wall without any additional structural elements, for example without a screwed connection or the like. The indicating pin drives through the rear front wall upon an overload of the pressure inside the cooking utensil until the control flange rests on the outer stop, and also the indicating pin returns in the opposite direction, again by overcoming the rear front wall by manually pressing it into its initial operating position.
It is furthermore known from the United Kingdom Patent Application GB 2 123 528 A to design a valve member in such a manner that a control piston constructed on the valve member controls a valve opening, which is formed as an elastic valve seat, which is provided in a recess in the lid of a cooking utensil. Upon an increasing pressure exceeding the operating pressure, the valve member, taking with it the valve seat, is finally driven so far out of the cooking utensil until an inherently stable stop piece constructed thereon rests on the lid, thereby covering the recess. Consequently two structural and operational parts consisting of entirely different materials are hereby needed to carry out all of the necessary functions.
The basic purpose of the invention is to design such a valve which is easily manufactured, yet be simpler and which maintains all functions carried out with such a valve.
The purpose is attained according to the invention with a valve member having a valve piston, which has means for indicating the pressure and is provided outside the cooking utensil, a control collar, which controls the valve opening and slides when a pressure in the cooking utensil exceeds the operating pressure through the valve opening and is otherwise provided within the cooking utensil, and an inherently stable stop piece constantly remaining within the cooking utensil, whereby the stop piece at least partially covers the valve opening and contacts the lid after the control collar has passed the valve opening, and whereby at least the control collar consists of an elastic material.
Such a valve member can easily consist of one piece so that not only its manufacture is very simple but also lowers the expenses for installation. The design of the invention allows the valve member together with the valve opening to carry out all the necessary functions, which otherwise can only be handled by several separate structural parts or even by several separately operating structural groups. The control collar can, in particular because of its elasticity, cover a wide range of operating pressures, whereby the deformed change of the control collar serves as the restoring force. The valve member can through a suitable design control both the start of boiling, after the air initially existing in the cooking utensil has been replaced with steam, and can also operate at a nonpermissible excess pressure as a safety valve.
The valve operates particularly efficiently as a pressure indicator when the valve opening is covered outside of the cooking utensil by a guide for the valve member fastened on the lid and spaced from said lid, which guide has a cylindrical bearing bore for the valve piston, which bearing bore is axially aligned with the valve opening, and the inside of which serves as an indicator for the pressureless state of the cooking utensil. Such a guide can be easily and inexpensively manufactured and mounted, for example, as a metal or plastic part fastened to the lid by spot welding and serves not only as a sliding bearing for the valve piston, but also prevents the steam blowing out of the valve from escaping directly upwardly, rather the escaping steam hits the guide and is laterally deflected so that there is a reduced danger when handling the cooking utensil to help prevent burning the hands of the operator. A pressureless state inside of the cooking utensil is clearly indicated, for example, after the ventilating through the valve, when the inside of the bearing bore has a color marking therein.
The operating pressure existing on the inside of the cooking utensil can be illustrated and indicated when conventionally peripherally extending annular grooves or similar markings are provided on the valve piston.
The internal pressure in the cooking utensil is controlled mainly by the steam being able to escape through the valve. A constant control operation is thereby particularly supported by the valve piston having, in a direction toward the cooking utensil, a preferably truncated constriction serving as a control edge, which constriction cooperates with and can abut the valve opening. The constriction can also be differently formed and can be equipped with a special control edge, corresponding details of the control edge are familiar from the state of the art. It is thereby advantageous when a flow connection between the inside of the cooking utensil and the outside is maintained when the valve piston contacts the valve opening. This is possible in a simple manner when the valve piston in the area of the constriction has at least one recess extending axially parallel on its periphery, which recess creates such a flow connection. Until the closure of the valve opening through the control edge at an increasing pressure in the cooking utensil, the air can escape during the start of boiling and is thereby replaced with steam. On the other hand, it is also in this manner assured that during a cooling off of the cooking utensil, for example in a water bath, an underpressure in the cooking utensil is safely avoided.
A particularly preferred embodiment of the invention is that the control collar is formed on the valve member in the form of an unobstructed peripherally extending lip seal ring, which in the relieved state is directed from the axis of symmetry of the valve member inclined outwardly and can be elastically deformed under an excess pressure in the cooking utensil. The seal lip of the lip seal ring ends in an annular edge, which can be pressed onto the lid and thereby seals the valve opening from the inside of the cooking utensil in a fluid tight arrangement.
The control collar is deformed with an increasing pressure within the interior of the cooking utensil and rests finally flat on the lid. The increasing deformation and a corresponding increase of the pressure can be read by the position of the valve piston, and, in particular, its annular grooves.
It is advantageous when the stop piece is designed as a plate covering the valve opening on the front side of the valve member, which front side is on the inside of the cooking utensil, so that the valve member is held securely in the valve opening even when the control collar has passed through the same and is outside of the cooking utensil. A further increase of the pressure is prevented in such a manner that the stop piece has at least one recess extending axially parallel on its periphery. The recess creates a flow connection of the cooking utensil with the outside when the stop piece rests on the valve opening.
The design of the inventive valve assures the possibility that the valve member consists therethrough of one or of several elastic materials. It is thereby undoubtedly particularly economical when the valve member is made of one elastic material, at most in parts, for example on a stop piece, supplemented by a reinforcement of an inherently stable material provided inside the value member in order to locally prevent a change in form.
In particular in the case of a one-piece design of the valve member consisting homogeneously of the same material, it becomes clear that the invention has created an inexpensive and functional control and indicating member for a cooking utensil of the above-identified type, which moreover can also be quickly exchanged on the lid by a man skilled in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be discussed in greater detail hereinafter in connection with the drawing using one exemplary embodiment.
In the drawings:
FIG. 1 is a schematic illustration of a valve of the invention in a first operating position;
FIG. 2 is a schematic illustration of a valve of the invention in a second operating position;
FIG. 3 is a partial cutaway illustration showing a third operating position with the first position; and
FIG. 4 is a schematic illustration of a fourth operating position of the valve.
DETAILED DESCRIPTION
The drawings show according to FIGS. 1 to 4 only a limited, cross-sectional area of a lid D of a cooking utensil, which operates with excess pressure, on an inside I of the cooking utensil. A valve opening S is provided in the lid D, which opening fluidly connects the inside I to the outside U and is controlled by a valve member 2. The lid D can be locked in a conventional manner on the cooking utensil, mostly via an edge-supported lock. The details for this are generally known and are not shown in the drawing.
A guide 3 for the valve member 2 provides a space at a height h above the lid D, which guide is fastened in a suitable manner to the lid D, for example, by means of resistance spot welding. The valve member 2 is thereby supported so as to be longitudinally movable with its upper area designed as a cylindrical valve piston 21 in the guide 3. Two annular grooves 21b are recessed on the outer surface 21a of the valve piston 21. The annular grooves can be colored in order to easily recognize the elevational position of the valve member 2 (FIGS. 3 and 4). When the valve piston 21 is so far below the guide 3 that the annular grooves 21b are not visible (FIGS. 1 and 2), then the distance of the upper front surface 21c of the valve piston 21 from the upper edge 31a of the bearing bore 31 offers a sufficient optical guide for the operator as to which operating state exists at that point. The indicating function is further improved when the inside 31b of the bearing bore 31 is colored. A corresponding plating 31c is indicated in the drawing. The drawing makes it clear that the arrangement of the valve member 2 in relationship to the guide 3 is such that the valve piston 21 in all operating positions of the valve will never completely disengage from the bearing bore 31.
A further support of the valve member 2 takes place in the valve opening 1, in which either (FIGS. 2 to 4) a valve shaft 22 concentric to the valve piston 21 is guided with a clearance or (FIG. 1) a conical constriction 21d of the valve piston 21 rests in a centered position in the valve opening 1. The valve shaft 22 is divided into a first shaft area 22a between the valve piston 21 and a control collar 23 on the circumference of the valve member 2, and into a further shaft area 22b between the control collar 23 and a stop piece 24 positioned at the end of the valve member 2, which end is distal the piston 21. The diameter of the valve shaft 22 extending through the valve opening 1 is dimensioned in such a manner that between the valve shaft 22 and the valve opening 1 there remains an annular chamber 10, which serves as a flow connection S between the inside I of the cooking utensil and the outside U of the cooking utensil. The flow connection(s) S is/are shown in the drawing (FIGS. 1, 3 and 4) by arrows.
When the valve member 2 during the start of boiling or after a cooling off of the cooking utensil rests with its own weight with its constriction 21d on the valve opening 1 because the pressure inside I of the cooking utensil has dropped, then, according to FIG. 1, a flow connection S is also maintained when first recesses 21e distributed on the periphery of the constriction 21d and extending into the outer surface 21a are cut into the valve piston 21. The control collar 23 is spaced axially from the valve piston 21 on the valve shaft 22 so far that it does not rest on the lid D when the constriction 21d, shown in FIG. 1, rests on the valve opening 1 so that flow medium can flow unhindered in and out through the flow connection S. In particular (FIG. 1 on the right) after a cooling off of the cooking utensil air is sucked in from the outside U through the annular chamber 10 so that a reduced pressure which hinders the opening of the cooking utensil is not created on the inside I of the cooking utensil. On the other hand (FIG. 1 on the left), the entire air above the food is during the start of boiling initially driven out and is successively replaced with steam, which contributes to an improvement in the preparation of food, for example in its taste and smell. The valve thus also acts as a so-called aroma valve.
The control collar 23 is designed like a lip seal ring corresponding to FIGS. 1 and 2 as a seal lip 23 pointing (in cross section) inclined outwardly and upwardly, which seal lip ends in an annular edge 23b extending circumferentially around the valve member 2. The annular edge 23b contacts during an increasing pressure inside I of the cooking utensil the underside of the lid D (FIG. 2) and interrupts the flow connection S between the interior of the cooking utensil and the outside U of the cooking utensil. The arrangement is designed such that this operating state can be easily recognized since the front surface 21c is then aligned flush with the upper edge 31a of the guide 3 (FIG. 2). The boiling starts in this position of the valve member 2 and results in a further pressure increase in the inside I until the actual cooking process occurring under an increased pressure starts. The associated operating pressure can be read on the valve piston 21, the annular grooves 21b of which become visible (FIG. 3 on the left) during an increasing pressure. The sealing lip 23a is thereby deformed against its deformation resistance until it rests circularly flat on the underside of the lid D. The heat supplied to the cooking utensil is at the same time throttled so that a pressure exceeding the associated operating pressure inside I of the cooking utensil is avoided.
FIG. 3 indicates (on the right) that the cooking utensil can be easily ventilated when a ventilating force in arrow direction F 1 is manually applied to the front surface 21c of the valve piston 21 until the control collar 23 is again spaced from the lid D, The stopping position of the ventilating force F 1 is easily determined by the subsequent contact of the constriction 21d with the upper edge 11 of the valve opening 1, which the operator safely recognizes even without a visual connection. Even then (FIG. 1, FIG. 3 on the right) the inside I is further ventilated through the first recesses 21e.
When the pressure in the cooking utensil is further increased beyond the permissible operating pressure when, for example, the heat supply is not interrupted or throttled, then the control collar 23 is driven through the valve opening 1, the annular change 10 of which is dimensioned accordingly. The stop piece 24 rests then on the valve opening 1 (FIG. 4). It is sufficient according to the invention that the stop piece 24 cannot also be driven out under pressure through the valve opening 1. On the other hand, second recesses 24b exist in the radial circumference 24a of the stop piece 24, which recesses create a renewed flow connection S between the inside I and the outside U so that a nonpermissible pressure in the cooking utensil is quickly reduced. In this manner, the valve of the invention represents also a safety valve.
The position of the valve member 2 in the valve opening 1, illustrated in FIG. 4, is stable, however, the valve member can be returned into the operating position of FIGS. 1 and 2. Accordingly, the valve piston 21 is manually returned by a restoring force applied in arrow direction F 2 to the front surface 21c of the valve piston 21 projecting outward from the guide 3, whereby the control collar 23 moves again through the valve opening 1 into the inside I.
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A valve is needed in a cooking utensil operating with an increased internal pressure, which valve is at the same time also capable of regulating the internal pressure, and, in particular, takes care that a nonpermissibly high internal pressure is reduced through a pressure release with the outside. Such valves are designed with many parts and are complicated and are difficult to handle also during cleaning. The invention provides a valve, which is manufactured essentially of a single piece of a rubber-elastic material, and permits at the same time to carry out all of the necessary functions.
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BACKGROUND OF THE INVENTION
This invention relates generally to power transmission elements, such as sprockets, for power transmission purposes and, more particularly, to split power transmission elements, that are mountable on an elongate driven shaft.
Power transmission element, such as gears, pulleys, sheaves and sprockets of various types are used in a variety of applications. In one common application found, for example, in conveyor systems used in the beverage industry, one or more sprockets are mounted on an elongate driven shaft. As the shaft rotates, the sprockets turn to advance the conveyor.
For any number of reasons, it may be necessary to remove or replace a sprocket or other such power transmission element. When conventional one-piece sprockets are used, it is necessary to expose at least one end of the shaft so that the sprockets can be removed or replaced over the exposed end. This is a complicated and cumbersome procedure that can take considerable time and require shutting down conveying operations for an extended period. Valuable production time can thus be lost.
To simplify the repair and replacement of such sprockets, various types of split sprockets have been developed. These sprockets, formed in two or more sections, can be mounted on, and removed from, a driven shaft while the shaft remains in place. Use of such split sprockets greatly simplifies the removal and replacement of the sprocket and reduces the machine "downtime" required to implement maintenance and repair. Such sprockets can be formed of various materials, such as thermoplastic as well as metals. Various means have been developed for fastening the split sprocket mating sections together and the sprocket to the driven shaft.
In one split sprocket arrangement, the sprocket sections are fastened to themselves and to the driven shaft by means of four screw fasteners oriented in planes perpendicular to the shaft. Although effective in clamping the sprocket to the shaft, this arrangement is somewhat complex and difficult to service as at least some of the fasteners are in difficult to reach locations. Furthermore, the use of four separate fasteners on each sprocket increases the likelihood that one or more fasteners will be misplaced during the servicing operation, possibly resulting in use of less than four fasteners or an unanticipated delay before the machine can be returned to service.
Another split sprocket arrangement includes two fasteners that lie parallel to the longitudinal axis of the driven shaft. Although only two fasteners are used, the orientation of the fasteners parallel to the shaft makes it difficult to reach the fasteners, particularly if the sprocket is near the machine housing or the machine frame is adjacent the shaft end. Furthermore, in such a coupling arrangement the fasteners develop no force in the direction toward the shaft and hence do not provide the clamping action that is preferred for securely mounting a sprocket to the shaft.
In view of the foregoing, it is a general object of the present invention to provide a new and improved power transmission element that is easily removed and replaced on a driven shaft.
It is a further object of the present invention to provide a new and improved power transmission element with means for providing a preferentially oriented clamping force for securely mounting the element to the driven shaft.
It is a still further object of the present invention to provide a new and improved split power transmission element that utilizes a minimum of fasteners to simplify installation and removal of the element.
It is a yet another object of the present invention to provide a new and improved split power transmission element that provides convenient access to the fasteners to further simplify installation and removal of the element.
It is a further object of the present invention to provide interlocking power transmission element body teeth for resisting shear forces and aligning the split element portions.
It is an additional further object of the present invention to provide a new and improved split power transmission element that has diagonally disposed fastener sleeves positioned to optimize clamping forces while allowing easy access for service and repair.
SUMMARY OF THE INVENTION
The invention provides a power transmission element mountable on a cylindrical shaft. The preferred power transmission element includes a pair of substantially identical element halves, each of which has a generally semi-circular configuration and includes a hub portion configured to overlie a portion of the shaft. Each of the element halves further includes a pair of substantially parallel fastener sleeves on opposite sides of the hub portion and oriented diagonally relative to the plane of the element half. The power transmission element further includes a fastener within each of the fastener sleeves for joining the element halves to each other to form a power transmission element having a center hub shaped and dimensioned to encircle the shaft.
The invention also includes as a sub unit a power transmission element half for coupling to a mating half to form a complete power transmission element mountable on a driven shaft. Each of the power transmission element halves comprises a generally semi-circular member having an outer circumference, a diametric edge and a pair of opposed faces. The power transmission element half further includes a hub portion shaped to overlie a portion of the driven shaft. The hub portion defines a central axis oriented coaxially with the longitudinal axis of the shaft when the power transmission element hub portion overlies the shaft. The power transmission element half further includes a first fastener sleeve on one side of the hub portion having a hollow interior extending diagonally through the opposed faces and lying in a plane oriented substantially parallel to the central axis of the hub and substantially perpendicularly to the diametric edge. The power transmission element half further includes a second fastener sleeve on the opposite side of the hub portion having a hollow interior oriented substantially parallel to the hollow interior of the first fastener sleeve. Each of the power transmission element halves also includes at least one set of alignment teeth matingly disposed on the power transmission element cross sectional surfaces which join the two power transmission element halves together. The alignment teeth also interlock and are angularly disposed to resist shearing forces tending to separate the sprocket halves. These alignment teeth can also be oriented to reinforce the vector clamping force applied via the fastener sleeves.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with the further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings, wherein like reference numerals identify like element, and wherein:
FIG. 1 is a perspective view of one embodiment of a split sprocket constructed in accordance with the invention.
FIG. 2 is a side elevation view of the split sprocket shown in FIG. 1.
FIG. 3 is a perspective view of another embodiment of a split sprocket constructed in accordance with the invention.
FIG. 4 is a side elevation view of the split sprocket shown in FIG. 3.
FIG. 5 is a cross-sectional view of the split sprocket shown in FIG. 3 taken along line 5--5 thereof.
FIG. 6 is a cross-sectional view of the split sprocket shown in FIG. 3 taken along line 6--6 thereof.
FIG. 7 is a cross-sectional view of the split sprocket shown in FIG. 3 taken along line 7--7 thereof.
FIG. 8 is a force diagram illustrating the various forces developed in an assembled split sprocket constructed in accordance with the invention.
FIG. 9 is a sectional view of one embodiment of a split sprocket constructed in accordance with one aspect of the invention illustrating the use of a metallic keyway insert.
FIG. 10 is a perspective view of the metallic keyway insert shown in FIG. 9.
FIG. 11 is a front elevation view of another embodiment of a split sprocket constructed in accordance with the invention showing the use of a plurality of gripping pads in the hub area thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, and in particular, to FIGS. 1 and 2, a split power transmission element embodying various features of the invention is shown. In the illustrated embodiment, the split power transmission element comprises a split sprocket 10. It will be appreciated, however, that the invention is equally applicable to other forms of power transmission elements such as gears, pulleys and sheaves.
As illustrated, the split sprocket 10 comprises a generally disk-shaped member having a central hub 12 shaped and dimensioned to encircle a driven shaft such as keyed (FIG. 9) or unkeyed drive shaft (not shown). The sprocket 10 comprises a pair of substantially identical sprocket halves 14 and 16, each half having a generally semi-circular configuration. Each of the sprocket halves 14 and 16 includes a generally diametrically extending lower edge 18, a pair of opposed faces 20 and 22, and a circumferential outer edge 24 having thereon formed a plurality of sprocket teeth 26. A hub portion 28 is also formed in each of the halves 14 and 16 and is shaped to overlie a portion of the drive shaft. Each of the hub portions 28 includes a hollow interior 30 that defines a central axis 32 that is oriented coaxially with the longitudinal axis of the shaft when the hub portion 28 overlies the shaft.
In the illustrated embodiment, the sprocket 10 is configured for mounting on a keyed drive shaft 34 (FIG. 9). Accordingly, one of the sprocket halves 14 includes a keyway 36 for receiving therein a drive shaft key. The other sprocket half 16, which otherwise can be identical with the first sprocket half 14, does not include the keyway 36. Preferably, both sprocket halves 14 and 16 are molded of a thermoplastic material.
FIGS. 3 and 4 illustrate another embodiment of the split sprocket 10 wherein it is intended that the split sprocket 10 be mounted on an unkeyed shaft. In this embodiment, neither of the sprocket halves 14 or 16 includes the keyway 36. The sprocket halves 14 and 16 are identical, and the same mold can be used for forming each half.
In use, the sprocket halves 14 and 16 are placed around the drive shaft 34 and are fastened to each other to thereby lock the sprocket 10 to the shaft 34. To this end, and as shown in FIGS. 3 and 4, each sprocket half 14 and 16 includes a pair of fastener sleeves 38 and 40 located on opposite sides of the hub portions 28. The sleeves 38 and 40 extend diagonally through the disk or body portions 20, 22 of each of the sprocket halves 14 and 16. As illustrated, the sleeves 38 and 40 are hollow and are oriented so that when the diametric edges 18 and the surfaces 19 and 21 and the surfaces 19 and 21 of the sprocket halves 14 and 16 are brought together, hollow interiors 42 of the opposed sleeves 38 and 40 on opposite sides of the diametric edges 18 are substantially coaxially aligned with each other. A pair of fasteners 44, one in each pair of aligned sleeves, fasten the sprocket halves 14 and 16 to each other. Preferably, each of the fasteners 44 comprises a metallic nut 46 and bolt 48. The nut 46 preferably comprises a threaded insert, having a fluted outer surface 50 and an enlarged or flanged end 52. Preferably, each nut 46 is press fitted within the fastener sleeve 38 or 40 as shown in FIG. 5.
As illustrated in FIG. 5, each of the fastener sleeves 38 and 40 is oriented so that its hollow interior 42 lies substantially within a plane oriented parallel relative to the central axis 32 of the hub portions 28 and perpendicularly relative to the diametric edge 18. In addition, each of the fastener sleeves 38 and 40 is oriented so that central axis of its hollow interior 42 passes substantially through the midline of the diametric edge 18. When so oriented, the forces F 1 and F 2 developed by each fastener 44 include a shear component directed axially relative to the drive shaft and a clamping force directed radially relative to the drive shaft. These vector forces are illustrated in FIG. 8. The clamping forces thus developed by each of the fasteners 44 serve to clamp the sprocket 10 firmly onto the drive shaft 34.
As further illustrated in FIG. 8, the vector forces exerted by the fasteners 44 also develop shear force components that tend to displace the sprocket halves 14 and 16 laterally relative to each other. To overcome this shearing tendency, means are provided for preventing axial movement of the sprocket halves 14 and 16 relative to each other as the fasteners 44 are tightened. In the illustrated embodiment, such preventing means comprise a plurality of interlocking alignment teeth 54 and sockets 56 formed in the diametric edges 18 of the sprocket halves adjacent the hub portions 28 thereof. As best seen in FIGS. 6 and 7, the sides of the interlocking teeth 54 are preferably oriented at an angle of approximately 15° relative to the plane of the sprocket 10 to best resist the shearing forces developed by the fasteners 44. Preferably, the fastener sleeves 38 and 40 are oriented at substantially a 30° angle relative to the plane of the sprocket 10. These angular relationships provide good clamping forces and resistance to these forces generally while still permitting east access to the fasteners 44 for service and repair of the sprocket 10. Further details of the latter feature will be described hereinafter.
In addition to developing a substantial clamping force for securing the sprocket 10 to the drive shaft 34, another advantage of the diagonally oriented fastener sleeves 38 and 40 is that access to the head of each of the fasteners 44 can be obtained from a position above and to the side of the sprocket 10 itself. This eliminates the need to approach the sprocket 10 from underneath, and the lateral offset permits the sprocket 10 to be disassembled without interference from an overlying structure such as a conveyor belt (not shown).
To maximize the torque capacity of the sprocket 10 when the sprocket 10 is mounted on the keyed shaft 34, one of the sprocket halves 14 is preferably provided with a metallic keyway insert 58 that engages a key 60 and helps distribute the resulting driving forces to the hub 12 while avoiding deformation of the thermoplastic material forming the sprocket 10. Such a variety of keyway insert 58 is shown and described in the concurrently filed copending application of David R. Gruettner and Robert J. Gladczak entitled, "Thermoplastic Power Transmission Element Having Increased Torque Capacity," the specification of which is incorporated by reference herein.
Another embodiment of the invention is illustrated in FIG. 11. In this embodiment, the sprocket 10 is intended for mounting on an unkeyed shaft (not shown). To improve the torque transfer characteristics between the shaft and the sprocket 10, a plurality of integrally molded gripping pads 62 are formed along the axial bore 30 of the hub 12. These pads 62 deform under the clamping forces developed as the fasteners 44 are tightened and thus serve to grip the shaft and thereby improve the torque transfer characteristic between the shaft and the sprocket 10.
Although various embodiments of the invention have been described, it will be appreciated that various modifications can be made. For example, various fastener types other than the nuts and bolts shown and described can be employed within the fastener sleeves. Furthermore, the thermoplastic material making up the sprocket halves is not critical. Additionally, the configuration and orientation of the sprocket teeth around the sprocket circumference are also not critical. Finally, as previously noted, the invention is equally well suited for use with other forms of power transmission elements, such as gears, pulleys and sheaves.
While a particular embodiment of the invention has been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention.
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A split power transmission element, such as a sprocket, mountable on a driven shaft. A pair of substantially identical sprocket halves each include a pair of aligned, hollow, fastener sleeves extending diagonally through the plane of the sprocket. A pair of fasteners within the sleeves join the sprocket halves to each other and clamp the sprocket onto the shaft. The diagonal orientation of the fastener sleeves permits convenient disassembly of the sprocket from an upwardly located, axially displaced position. The sprocket halves are substantially identical and can be economically molded using a single mold. A keyway insert distributes driving forces throughout the sprocket hub and increases the maximum torque capacity of the sprocket.
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BACKGROUND OF THE INVENTION
This is a continuation-in-part of U.S. application Ser. No. 825,513 filed Jan. 31, 1986, now abandoned.
The novel compounds of the present invention are adenosine analogs having some of the same activities as adenosine. The compounds have a favorable ratio of affinities at A 1 and A 2 receptors and highly desirable central nervous system and cardiovascular activities, such as, analgesic, antipsychotic, sedative, antihypertensive and antianginal.
U.S. Pat. No. 3,590,029 discloses a series of 2-amino-N 6 -adenosine derivatives which may also include 2-amino-N 6 -diphenylalkyladenosines which have circulatory and cardiac activity. German publication No. 2,406,587 discloses and claims N 6 -diphenylalkyladenosines wherein the alkyl is required to be a branched chain having use as hypolipemic agents. Further, U.S. applications Ser. No. 756,922, filed July 18, 1985, now U.S. Pat. No. 4,657,898 and U.S. application Ser. No. 756,004, filed July 17, 1985, now U.S. Pat. No. 4,657,897, parent U.S. application Ser. No. 621,943, filed June 22, 1984, now abandoned which was a continuation-in-part of U.S. Ser. No. 519,284 filed Aug. 1, 1983, also now abandoned, claim N 6 -diphenylalkyladenosines wherein the alkyl is limited to straight chain moieties having highly desirable central nervous system and cardiovascular activities as now found for the novel compounds of the present invention.
SUMMARY OF THE INVENTION
The present invention relates to a compound of the formula (I) ##STR3## wherein
Ar is (1) phenyl, (2) 1- or 2-naphthalenyl, (3)2- or 3-thienyl, (4) 2- or 3-furanyl, (5) 2-, 4-, or 5-thiazyl, (6) 2-, 3-, or 4-pyridyl, or (7) 2-pyrimidyl wherein each of (1), (2), (3), (4), (5), (6) or (7) is unsubstituted or substituted with at least one of lower alkyl, halo, trifluoromethyl, hydroxy, lower alkoxy, lower acyloxy, amino, N-lower monoalkyl or N,N-lower dialkylamino, lower thioalkyl, lower alkylsulfonyl, or nitro;
A is a bond, ##STR4## wherein q, q' or q" are independently an integer of one to four, inclusive;
n and m are independently an integer of from zero to three, inclusive, with the provision that if A is a bond then the sum of n and m must be at least two; or at least one if A is other than a bond;
R 1 is hydrogen or lower alkyl;
G is hydrogen, lower alkyl, benzyl, lower acyl, benzoyl;
x is an integer of zero or one;
D is hydrogen, halogen, amino, acylamino, lower alkylamino, or lower cycloalkylamino;
E is hydrogen, halogen, amino, or hydrazinyl;
Z is (1) --(CH 2 )--Q wherein Q is selected from the group consisting of hydrogen, hydroxy, halogen, cyano, azido, amino, lower alkoxy, lower acyloxy, lower thioalkyl, lower sulfonylalkyl, ##STR5## wherein L is 0-4; and
R 6 is hydrogen or when L is 0 then R 6 may also be a side chain of a naturally occurring amino acid, such as, benzyl as found in a phenylalanine ester, or isopropyl as found in a valinyl ester; or ##STR6## wherein k is 0-4;
--P(═Y)(OR") 2 , --P(═Y)(OR")(OR'") and taken together with R 3 is ##STR7## wherein Y is oxygen or sulfur and R" and R'" are independently hydrogen or lower alkyl; or (2) ##STR8## wherein J is O, S, NR 7 wherein R 7 is hydrogen, lower alkyl or cycloalkyl of from 3 to 7 carbons such as cyclopropyl, cyclobutyl, cyclopentyl and the like or 1- or 2-methylcyclopropyl, 1-, or 2-ethylcyclobutyl and the like; and
T is (a) NR 4 R 5 wherein R 4 is straight chain lower alkyl having 1-4 carbon atoms; hydroxy, lower alkoxy or halogen substituted straight chain lower alkyl having 1-4 carbon atoms; cyclopropyl; secondary alkyl having 3-6 carbon atoms; hydroxy, lower alkoxy or halogen substituted secondary alkyl having 3-6 carbon atoms; alkenyl having 3 to 6 carbon atoms; aralkyl having 1 to 4 carbons in the alkyl chain and optionally substituted in the aryl nucleus with hydroxy, halogen, lower alkoxy or lower alkyl groups; and heteroarylalkyl having 1 to 4 carbons in the alkyl chain and optionally substituted in the heteroaryl nucleus with hydroxy, halogen, lower alkoxy or lower alkyl groups, and
R 5 is hydrogen, or straight chain lower alkyl having 1 to 4 carbons; or (b) OR 4 wherein R 4 is as defined above;
R 2 and R 3 are independently selected from the group consisting of hydrogen, lower alkanoyl, benzoyl, one of R 2 or R 3 is --P(═Y)(OR") 2 or --P(═Y)(OR")(OR'"), wherein R" and R'" are as defined above, and R 2 and R 3 are taken together to form lower alkylidene or to form ##STR9## wherein Y and R" are as defined above; and pharmaceutically acceptable base salts thereof when possible or pharmaceutically acceptable acid addition salts thereof.
The present invention also relates to a pharmaceutical composition for treating diseases of the central nervous and cardiovascular system comprising an analgesic, antipsychotic, sedative, antihypertensive or antianginal effective amount of a compound having the formula I as defined above with a pharmaceutically acceptable carrier. Additionally, the instant invention is a method of treating mammals suffering from pain, psychosis, anxiety, hypertension, or angina by administering to such mammals a dosage form of a compound of the formula I as defined above.
DETAILED DESCRIPTION OF THE INVENTION
In the compounds of the formula I, the term "lower alkyl" is meant to include a straight or branched alkyl group having from 1 to 6 carbon atoms such as, for example, methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, isobutyl, tert-butyl, amyl, isoamyl, neopentyl, hexyl, and the like.
Halogen includes particularly fluorine, chlorine or bromine.
Lower alkoxy and thioalkoxy are O-alkyl or S-alkyl of from 1 to 6 carbon atoms as defined above for "lower alkyl."
Lower alkanoyl is a straight or branched ##STR10## group of from 1 to 6 carbon atoms in the alkyl chain as defined above.
Lower acyloxy is ##STR11## wherein alkyl is a straight or branched chain of from 1 to 6 carbon atoms as defined above.
Lower acyl is of 1 to 6 carbon atoms in a straight or branched chain alkyl group.
Lower cycloalkyl is of from 3 to 10 carbons wherein the ring is of from 3 to 7 carbons.
The compounds of formula I are useful both in the free base form, in the form of base salts where possible, and in the form of acid addition salts. The three forms are within the scope of the invention. In practice, use of the salt form amounts to use of the base form. Appropriate pharmaceutically acceptable salts within the scope of the invention are those derived from mineral acids such as hydrochloric acid and sulfuric acid; and organic acids such as methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, and the like, giving the hydrochloride, sulfamate, methanesulfonate, benzenesulfonate, p-toluenesulfonate, and the like, respectively or those derived from bases such as suitable organic and inorganic bases. Examples of suitable inorganic bases for the formation of salts of compounds of this invention include the hydroxides, carbonates, and bicarbonates of ammonia, sodium, lithium, potassium, calcium, magnesium, aluminum, zinc, and the like.
Salts may also be formed with suitable organic bases. Bases suitable for the formation of pharmaceutically acceptable base addition salts with compounds of the present invention include organic bases which are nontoxic and strong enough to form such salts. These organic bases form a class whose limits are readily understood by those skilled in the art. Merely for purposes of illustration, the class may be said to include mono-, di-, and trialkylamines, such as methylamine, dimethylamine, and triethylamine; mono-, di- or trihydroxyalkylamines such as mono-, di- and triethanolamine; amino acids such as arginine, and lysine; guanidine; N-methylglucosamine; N-methylglucamine; L-glutamine; N-methylpiperazine; morpholine; ethylenediamine; N-benzylphenethylamine tris(hydroxymethyl)aminomethane; and the like. (See for example, "Pharmaceutical Salts," J. Pharm. Sci. 66(1): 1-19 (1977)).
The acid addition salts of said basic compounds are prepared either by dissolving the free base of compound I in aqueous or aqueous alcohol solution or other suitable solvents containing the appropriate acid or base and isolating the salt by evaporating the solution, or by reacting the free base of compound I with an acid as well as reacting compound I having an acid group thereon with a base such that the reactions are in an organic solvent, in which case the salt separates directly or can be obtained by concentration of the solution.
The compounds of the invention may contain an asymmetric carbon atom at one of each of the two carbons connecting groups R 1 when R 1 is not hydrogen, the moiety having n and m when n is not equal to m, and Ar to the N of the amino adenosine. Thus, the invention includes the individual stereoisomers, and mixtures thereof. The individual isomers may be prepared or isolated by methods known in the art. Particularly, when Q is ##STR12## when R 6 is not hydrogen then the compounds of the invention include both separate enantiomers and the racemate thereof.
A preferred embodiment of the present invention includes a compound of formula I wherein G and R 1 are hydrogen; Ar is phenyl, 2-thienyl, or 2-furanyl (all of which may either be substituted or unsubstituted); x is zero; D and E are hydrogen; Q is hydroxy; R 2 and R 3 are hydrogen, acetyl, benzoyl or when taken together forms isopropylidene; and the sum of n and m is no more than seven.
A more preferred embodiment includes the definitions of G, R 1 , Ar, x, D, E, Q, R 2 and R 3 for the preferred embodiment above and additionally includes the definitions A is a bond, and the sum of n and m is also limited to two or three.
Generally, the compounds of formula I may be conveniently synthesized by reacting a 6-halopurine riboside of formula II with the requisite compound of formula III which is illustrated as follows: ##STR13## wherein Ar, R 1 , B, n, m, A, D, E, Q, R 3 and R 2 are as defined above and Hal is halogen, preferably chlorine or bromine.
The reaction is in an inert solvent, such as alcohol, or an aprotic solvent such as dimethylformamide between from 25° to about 130° C., preferably at reflux in ethanol.
It is useful to add a base such as triethylamine, or calcium carbonate to neutralize the hydrogen halide formed as a byproduct of the reaction, but this can also be accomplished by using an extra equivalent of the compound of formula III. It is also convenient, although not necessary, to protect the ribofuranose hydroxyl groups as acetate or benzoate esters which can be removed with ammonium hydroxide or sodium methoxide following the synthesis of the N 6 -substituted adenosines of the compounds of formula I for which it is desired to make R 2 and R 3 hydrogen.
The compound of formula II above may be one having D and E as hydrogen or halogen. The compounds of formula I wherein D and E are other than hydrogen or halogen may, thus, also be prepared in a stepwise manner from the compounds of formula I wherein D and E are halogen by replacing the halogen with D or E when each is other than halogen. This is accomplished using nucleophilic displacement conditions with a compound of the formula D--H or E--H wherein D or E is other than hydrogen or halogen. This replacement may be accomplished before removing the protective groups as discussed above.
The compounds of formula I wherein x is one can be prepared by peracid oxidation of the corresponding compounds of formula I wherein x is zero using procedures known to a skilled artisan.
Other variations in the above discussed reactions are within the skill in the art and the above discussion is thus not considered limiting.
The compounds of formula I and the pharmaceutically acceptable acid addition salts thereof are found to possess affinities for adenosine receptors (designated A 1 and A 2 receptors for convenience). These compounds are active in animal tests which are predictive of neuroleptic activity for the treatment of major psychoses such as schizophrenia. The compounds of the invention also have sedative/hypnotic properties and as such, are useful for the treatment of sleep disorders. These compounds also have analgesic properties and as such, are useful in the treatment of pain.
In addition, the compounds of the present invention are useful as antihypertensive agents for the treatment of high blood pressure. They also increase coronary blood flow and as such are useful in the treatment of angina and myocardial ischemia.
PHARMACOLOGICAL EVALUATION
Adenosine Receptor Binding--A 1 Receptor Affinity (RBA1 )
Preparation of Membranes
Whole brain minus cerebellum and brainstem from male Long-Evans rats (150-200 g) was homogenized in 30 volumes of ice-cold 0.05M Tris-HCl buffer pH 7.7 using a Brinkman Polytron PT-10, (setting number 6 for 20 seconds) and centrifuged for ten minutes at 20,000 xg (Sorvall RC-2), 4° C. The supernatant was discarded, and the pellet was resuspended and centrifuged as before. The pellet was resuspended in 20 ml Tris-HCl buffer containing two International Units/ml of adenosine deaminase (Sigma type III from calf intestinal mucosa), incubated at 37° C. for 30 minutes, then subsequently at 0° C. for ten minutes. The homogenate was again centrifuged, and the final pellet was resuspended in ice-cold 0.05M Tris-HCl buffer pH 7.7 to a concentration of 20 mg/ml original wet tissue weight and used immediately.
Assay Conditions
Tissue homogenate (10 mg/ml) was incubated in 0.05M Tris-HCl buffer pH 7.7 containing 1.0 nM [ 3 H]--N 6 -cyclohexyladenosine ([ 3 H]--CHA) with or without test agents in triplicate for one hour at 25° C. Incubation volume was 2 ml. Unbound [ 3 H]--CHA was separated by rapid filtration under reduced pressure through Whatman glass fiber (GF/B) filters. The filters were rinsed three times with 5 ml of ice cold 0.05M Tris-HCl buffer pH 7.7. The radio-labeled ligand retained on the filter was measured by liquid scintillation spectrophotometry after shaking the filters for one hour or longer on a mechanical shaker in 10 ml of Beckman Ready-Solv HP scintillation cocktail.
Calculations
Nonspecific binding was defined as the binding which occurred in the presence of 1 mM theophylline. The concentration of test agent which inhibited 50% of the specific binding (IC 50 ) was determined by nonlinear computer curve fit. The Scatchard plot was calculated by linear regression of the line obtained by plotting the amount of radioligand bound (pmoles/gram of tissue) ##EQU1## Since the amount of radioligand bound was a small fraction of the total amount added, free radioligand was defined as the concentration of (nM) of radioligand added to the incubation mixture. The Hill coefficient was calculated by linear regression of the line obtained by plotting the log of the bound radioligand vs the log of the ##EQU2## The maximal number of binding sites (B max ) was calculated from the Scatchard plot.
Adenosine Receptor Binding--A 2 Receptor Affinity (RBA2)
Tissue Preparation
Brains from 200-500 g mixed sex Sprague-Dawley rats were purchased from Pel-Freez (Rogers, Ark.). Fresh brains from male Long-Evans hooded rats (Blue Spruce Farms, Altamont, NY) gave essentially identical results. Brains were thawed and then kept on ice while the striata were dissected out. Striata were disrupted in 10 vol of ice-cold 50 mM Tris.HCl (pH 7.7 at 25° C., pH 8.26 at 5° C.) (Tris) for 30 seconds in a Polytron PT-10 (Brinkmann) at setting 5. The suspension was centrifuged at 50,000 xg for ten minutes, the supernatant discarded, the pellet resuspended in 10 vol ice-cold Tris as above, recentrifuged, resuspended at 1 g/5ml, and stored in plastic vials at -70° C. (stable for at least six months). When needed, tissue was thawed at room temperature, disrupted in a Polytron, and kept on ice until used.
Incubation Conditions
All incubations were for 60 minutes at 25° C. in 12×75 mm glass tubes containing 1 ml Tris with 5 mg original tissue weight of rat weight of rat striatal membranes, 4 nM [ 3 H]--N-ethyl adenosine-5'-carboxamide ([ 3 H]NECA), 50 nM N 6 -cyclopentyladenosine (to eliminate A 1 receptor binding), 10 mM MgCl 2 , 0.1 units/ml of adenosine deaminase and 1% dimethylsulfoxide. N 6 -Cyclopentyladenosine was dissolved at 10 mM in 0.02N HCl and diluted in Tris. Stock solutions and dilutions of N 6 -cyclopentyladenosine could be stored at -20° C. for several months. Test compounds were dissolved at 10 mM in dimethylsulfoxide on the same day as the experiment, and diluted in dimethylsulfoxide to 100×the final incubation concentration. Control incubations received an equal volume (10 μl) of dimethylsulfoxide; the resulting concentration of dimethylsulfoxide had no effect on binding. [ 3 H]NECA was diluted to 40 nM in Tris. The membrane suspension (5 mg/0.79 ml) contained sufficient MgCl 2 and adenosine deaminase to give 10 mM and 0.1 units/ml, respectively, final concentration in the incubation. For test compounds with IC 50 values less than 1 μM, the order of additions was test compound (10 μl), N 6 -cyclopentyladenosine (100 μl), [ 3 H]NECA (100 μl), and membranes (0.79 ml). For test compounds with IC 50 values greater than 1M and limited water solubility, the order of additions (same as volumes) was test compound, membranes, N 6 -cyclopentyladenosine, and [ 3 H]NECA. After all additions, the rack of tubes was vortexed, and the tubes were then incubated for 60 min at 25° C. in a shaking water bath. The rack of tubes was vortexed an additional time halfway through the incubation.
Incubations were terminated by filtration through 2.4 cm GF/B filters under reduced pressure. Each tube was filtered as follows: the contents of the tube were poured on the filter, 4 ml of ice-cold Tris were added to the tube and the contents poured onto the filter, and the filter was washed twice with 4 ml of ice-cold Tris. The filtration was complete in about twelve seconds. Filters were put in scintillation vials, 8 ml of Formula 947 scintillation fluid added, and the vials left overnight, shaken, and counted in a liquid scintillation counter at 40% efficiency.
Data Analysis
Nonspecific binding was defined as binding in the presence of 100 μM N 6 -cyclopentyladenosine, and specific binding was defined as total binding minus nonspecific binding. The IC 50 was calculated by weighted nonlinear least squares curve-fitting to the mass-action equation. ##EQU3## where Y is cpm bound
T is cpm total binding without drug
S is cpm specific binding without drug
D is the concentration of drug and
K is the IC 50 of the drug
Weighting factors were calculated under the assumption that the standard deviation was proportional to the predicted value of Y. Nonspecific binding was treated as a very large (infinite) concentration of drug in the computer analysis.
The IC 50 values (nM) for adenosine A 1 and A 2 receptor affinity are reported in the Table I below.
TABLE I______________________________________Example Number RBA-1 (nM)IC.sub.50 IC.sub.50 RBA-2 (nM)______________________________________1 28 802 32 2003 7.3 8.64 6500 350005 52 4206 18 677 16 1508 31 3209 5.6 8710 110 46011 410 320012 70 1200______________________________________
ANTIPSYCHOTIC EVALUATION
The compounds of the invention are new chemical substances which are useful as pharmaceutical agents for the treatment of psychoses. The antipsychotic activity of representative compounds of the invention was established by the Mouse Activity and Screen Test Procedure (MAST) described below.
Animals
Nine unfasted Swiss-Webster male mice weighing 20-30 g are equally divided into three groups for each drug dose to be tested. That is, data for each dose level was generated by three separate groups of three mice each.
Drugs
A minimum of three dose levels (10, 30, and 100 mg/kg) are tested for each drug. Treatments are administered intraperitoneally one hour prior to testing. All dosages are calculated as parent compound and given in volumes of 10 ml/kg. Compounds are dissolved or suspended in 0.2% Methocel. Control animals are injected with Methocel.
Testing
A two part testing procedure is started one hour postinjection. First, the screen test (ST) is performed (see Pharmac. Biochem. Behav. 6, 351-353, 1977). Briefly this test consists of placing mice on individual wire screens which are then rotated 180 degrees at the start of a 60 second observation period. The number of mice falling off the inverted screen is recorded.
Immediately following the screen test, the final phase of testing is initiated by placing each group of three mice in one actophotometer (Life Sciences, 22, 1067-1076, 1978). The actophotometer consists of a cylindrical chamber whose center is occupied by another cylinder which contains the illumination for six photocells located on the perimeter of the chamber. Six light-beam interruptions equal one count. Locomotor activity is recorded by computer at ten minute intervals for 60 minutes.
Data
The data obtained from the screen test are expressed as percent of mice falling off the screen. Data derived from locomotor activity of drug treated mice are compared to the activity of vehicle treated animals and are expressed as percent inhibition of spontaneous locomotion. All percentages reported for inhibition of locomotion (LI) are based upon data accumulated for one hour. Both phases of testing are graded: A=60-100%; C=31-59%; and N=0-30%. An overall dose rating is obtained by the following criteria:
______________________________________Inhibition of Screen Test DoseLocomotion Rating with Failure Rating = Rating______________________________________A -- N or C = AA -- A = CC -- N or C = CAll other combinations = N______________________________________
LAD refers to the lowest dose at which an A rating is achieved. Compounds which exhibit an overall dose rating of A at a dose of 100 milligrams/kilogram or less are considered active. Utilizing this procedure, an overall dose rating of A was obtained for the noted compound in Table II at the indicated dose. The compounds are idendified in the Examples.
TABLE II______________________________________ Inhibition Inhibition of of motor screen testExample Dose (IP) activity (%) failure (%)______________________________________1 .05 0.3 43 11 1.0 48 0 3.0 38 0 10 92 0 30 98 22 100 100 442 3 19 11 10 69 0 30 90 03 0.03 17 0 0.1 40 0 0.3 70 0 1.0 85 0 3.0 89 0 10 93 04 (RAT orally (PO)) 1 2 11 3 15 0 10 2 05 3 16 11 10 10 0 30 -4 06 3 11 0 10 16 0 30 51 07 1.0 5 0 3.0 21 0 10.0 82 08 3 22 0 10 35 0 30 73 09 3 43 0 10 86 0 30 94 010 3 -7 11 10 12 0 30 49 2211 3 15 11 10 -10 0 30 34 012 3 -4 0 10 5 0 30 20 0______________________________________
Representative compounds of the invention (identified in the Examples) were also tested for antipsychotic activity according to the following protocol (SIDR or SIDSM). The noted compound has the indicated ED 50 values (mg/kg) and is considered active as an antipsychotic agent in the test procedure.
Procedure
Mature male Long-Evans rats (SIDR) or squirrel-monkeys (SIDSM) are conditioned to push a lever in order to avoid a painful electric footshock. If the animals fails to push the lever, he receives a shock every ten seconds until the lever is pushed. Shocks can be terminated by pushing the lever. Thereafter, as long as the lever is pushed at least once every 20 seconds, there will be no shock.
Each animal acts as its own control; one weekly session is used to establish baseline behavior and another session later in the week is used as a drug session. Once patterns of avoidance are established, the effects of standard and unknown compounds are studied.
When tested by the above procedure representative compound of Example 1 as shown hereinafter shows an ED 50 in the SIDR protocol (that is in the rat) as described above of 0.55 mg/kg and in the SIDSM (that is in the squirrel-monkey) as described above of 0.52 mg/kg.
RESPONSE EVALUATION
All events are electronically programmed and the response to these events counted or used as feed-back to the program.
ANTIHYPERTENSIVE EVALUATION (AHP3)
The usefulness of the compounds of the present invention as antihypertensive agents is demonstrated by their effectiveness in standard pharmacological test procedures, for example, in causing a significant decrease in mean arterial blood pressure in the conscious rat. This test procedure is described in the following paragraphs.
A Method for the Direct Monitoring of Aortic Blood
Pressure and Heart Rate from Conscious Rats
The continuous monitoring of pulsatile blood pressure (BP) from unrestrained conscious rats surgically equipped with polyethylene cannulas was accomplished by means of a computer assisted data capture scheme (CADCS). The basic elements of the methodology are the cannulation procedure and the CADCS.
Method
Cannulation Procedure
Rats were anesthetized with Telazol (1:1 tiletamine HCl and zolazepam HCl); 20-40 mg/kg IM and the descending aorta exposed via a midline incision. Cannulas fabricated from polyethylene tubing were inserted into the aorta via an undersized puncture hole below the renal arteries. The puncture hole was made by a 23 G disposable needle with a section of the aorta clamped off above and below the puncture site. The cannulas, consisting of a PE100 (0.86 mm ID) body and a PE50 (0.58 mm ID) tip, were attached to a trocar, inserted through the psoas muscle, and passed subcutaneously along the midline of the back and externalized between the ears. The cannulas were anchored to the psoas muscle and between the scalulae (3-0 green braided suture). The midline incision was closed in two steps (muscle first, skin second) using continuous over-and-over sutures (4-0 chronic). Each rat was then given penicillin 30,000 units subcutaneously (Penicillin G Procaine Sterile Suspension).
The rats were fitted with a harness-spring-swivel assembly designed to protect the cannula and to provide the rat relative freedom of movement. The harnesses were fabricated from nylon hook and loop tape cemented to a metal plate to which spring wires (18-8 stainless steel) were attached to brass swivels. Each polyethylene cannula was channeled through a spring and connected through a swivel to a pressure transducer (Model P23Gb; Statham Instruments; Hato Rey, Puerto Rico) and an infusion pump (Sage model 234-7; Orion Research, Cambridge MA) by means of PE100 tubing. While on test, each rat received a continuous slow infusion of heparinized saline solution (approximately 400 μl or 40 units of heparin per 24 hours period) to prevent clot formation. Additional "flushes" of the cannula with heparinized saline were carried out when the aortic pulse pressure (systolic minus diastolic) was less than 25 mm Hg.
CADCS
The pulsatile blood pressure and heart rate of each of 32 rats was monitored every minute by means of two in-laboratory microcomputers communicating directly with a data concentrator computer. The data were first stored on the data concentrator disk and then transferred to a magnetic tape for analysis and report generation by the main research computer. The overall scheme involved modulating the primary signal from the pressure transducer, generating the primary data set of the one-minute values for systolic, diastolic, and mean blood pressures and heart rate by the in-lab microcomputer and the storage, analysis, and report generation by the main research computer.
The transducers were connected to analog signal conditioning modules. The modules provided a regulated excitation voltage for the transducers, amplification as required to interface the microprocessors and an active low pass filter to compensate for the pressure wave form distortion produced by the flexible, fluid filled, narrow cannula. The distortion was 22-26 Hz and this provided a reliable estimate of both systolic and diastolic blood pressure.
The microcomputers (one for each of two groups of 16 rats) were connected to the input components through the module interface units, an analog-to-digital converter for the pressure wave form signal and the digital inputs for the dose and event marker switches. The microcomputer controlled the sequential acquisition of data from the modular interface units through an internal synchronous time-of-day clock/time base generator. Utilizing the time base generator as a reference, the blood pressure values and the marker switch status for each of the 32 stations were sampled every ten msec. The microcomputer processed each blood pressure sample as it was received to produce "running average" values for heart rate, and mean, systolic and diastolic blood pressure.
When tested by the above procedure, compounds of the Examples as noted produced the following changes in MAP (mean arterial pressure) and heart rate.
TABLE III______________________________________ Dose Maximum BP ↓Example Number Mg/Kg MAP______________________________________1 1 13% 3 23% 10 23%3 3 43%7 10 32%9 3 10%10 10 10%11 10 5%12 10 23%______________________________________
LAD refers to the lowest dose tested at which a 10% reduction in blood pressure for four consecutive hours is achieved.
Accordingly, the present invention also includes a pharmaceutical composition for treating psychoses, sleep disorders, pain, hypertension or angina comprising a corresponding antipsychotic, sedative, analgesic, antihypertensive or antianginal effective amount of a compound of the formula I as defined above together with a pharmaceutically acceptable carrier.
The present invention further includes a method for treating psychoses, sleep disorders, pain, hypertension, or angina in mammals suffering therefrom comprising administering to such mammals either orally or parenterally a corresponding pharmaceutical composition containing a compound of the formula I as defined above in appropriate unit dosage form.
For preparing pharmaceutical compositions from the compounds described by this invention, inert, pharmaceutically acceptable carriers can be either solid or liquid. Solid form preparations include powders, tablets, dispersible granules, capsules, cachets, and suppositories. A solid carrier can be one or more substance which may also act as diluents, flavoring agents, solubilizers, lubricants, suspending agents, binders or tablet disintegrating agents; it can also be encapsulating material. In powders, the carrier is a finely divided solid which is in admixture with the finely divided active compound. In the tablet the active compound is mixed with carrier having the necessary binding properties in suitable proportions and compacted in the shape and size desired. The powders and tablets preferably contain from 5 to 10 to about 70 percent of the active ingredient. Suitable solid carriers are magnesium carbonate, magnesium sterate, talc, sugar, lactose, pectin, dextrin, starch, gellatin, tragacanth, methylcellulose, sodium carboxymethylcellulose, a low melting wax, cocoa butter, and the like. The term "preparation" is intended to include the formulation of the active compound with encapsulating material as carrier providing a casule in which the active component (with or without other carriers) is surrounded by carrier, which is thus in association with it. Similarly, cachets are included. Tablets, powders, cachets, and capsules can be used as solid dosage forms suitable for oral administration.
For preparing suppositories, a low melting wax such as a mixture of fatty acid glycerides or cocoa butter is first melted, and the active ingredient is dispersed homogeneously therein as by stirring. The molten homogeneous mixture is then poured into convenient sized molds, allowed to cool and thereby to solidify.
Liquid form preparations include solutions, suspensions, and emulsions. As an example may be mentioned water or water propylene glycol solutions for parenteral injection. Liquid preparations can also be formulated in solution in aqueous polyethylene glycol solution. Aqueous solutions suitable for oral use can be prepared by dissolving the active component in water and adding suitable colorants, flavors, stabilizing and thickening agents as desired. Aqueous suspensions suitable for oral use can be made by dispersing the finely divided active component in water with viscous material, i.e., natural or synthetic gums, resins, methylcellulose, sodium carboxymethylcellulose, and other well-known suspending agents.
Also included are solid form preparations which are intended to be converted, shortly before use, to liquid form preparations for either oral or parenteral administration. Such liquid forms include solutions, suspensions, and emulsions. These particular solid form preparations are most conveniently provided in unit dose form and as such are used to provide a single liquid dosage unit. Alternately, sufficient solid may be provided so that after conversion to liquid form, multiple individual liquid doses may be obtained by measuring predetermined volumes of the liquid form preparation as with a syringe, teaspoon, or other volumetric container. When multiple liquid doses are so prepared, it is preferred to maintain the unused portion of said liquid doses at low temperature (i.e., under refrigeration) in order to retard possible decomposition. The solid form preparations intended to be converted to liquid form may contain, in addition to the active material, flavorants, colorants, stabilizers, buffers, artificial and natural sweeteners, dispersants, thickeners, solubilizing agents, and the like. The liquid utilized for preparing the liquid form preparation may be water, isotonic water, ethanol, glycerine, propylene glycol, and the like as well as mixtures thereof. Naturally, the liquid utilized will be chosen with regard to the route of administration, for example, liquid preparations containing large amounts of ethanol are not suitable for parenteral use.
Preferably, the pharmaceutical preparation is in unit dosage form. In such form, the preparation is subdivided into unit doses containing appropriate quantities of the active component. The unit dosage form can be a packaged preparation, the package containing discrete quantities of preparation, for example, packeted tablets, capsules, and powders in vials or ampules. The unit dosage form can also be a capsule, cachet, or tablet itself or it can be the appropriate number of any of these in packaged form.
The quantity of active compound in a unit dose of preparation may be varied or adjusted from 0.01 mg 500 mg preferably to 0.1 to 50 mg according to the particular application and the potency of the active ingredient. The compositions can, if desired, also contain other compatible therapeutic agents.
In therapeutic use as described above, the mammalian dosage range for a 70 kg subject is from 0.01 to 150 mg/kg of body weight per day or preferably 0.5 to 50 mg/kg of body weight per day. The dosages, however, may be varied depending upon the requirements of the patient, the severity of the condition being treated, and the compound being employed.
Determination of the proper dosage for a particular situation is within the skill of the art. Generally, treatment is initiated with smaller dosages which are less than the optimum dose of the compound. Thereafter the dosage is increased by small increments until the optimum effect under the circumstances is reached. For convenience, the total daily dosage may be divided and administered in portions during the day if desired.
The following Examples further illustrate the invention, but are not meant to be limiting thereto.
EXAMPLE 1
N6-((1-Phenylcyclopropyl)methyl)adenosine
A mixture of 6-chloropurine riboside (8.61 g, 30 mmol), (1-phenylcyclopropyl)methylamine (4.41 g, 30 mmol) and triethylamine (6.06 g, 60 mmol) are refluxed in stirring ethanol (300 mL) under N 2 for 20 h. On cooling to 0° the product crystallized. Vacuum filtration and drying in vacuo gives N6-((1-phenylcyclopropyl)methyl)adenosine (9.24 g, 79%) as a very pale khaki solid m.p. 118°-23° C. Found: C, 59.58; H, 5.77; N, 17.49%. C 20 H 23 N 5 O 4 calculated requires: C, 60.45; H, 5.79; N, 17.63%.
(1-Phenylcyclopropyl)methylamine
Phenylacetonitrile (5.85 g, 50 mmol) in DMSO (dimethylsulfoxide) (20 mL) is added dropwise over 45 min to a slurry of oil-free NaH (3.0 g, 125 mmol) in stirred DMSO (100 mL) at 25° under N 2 . Vigorous gas evolution occurs. After a further 30 min 1,2-dibromoethane (14.1 g, 75 mmol) in DMSO (20 mL) is added dropwise over 1 h. The reaction mixture turns purple, heats up to about 50°, and further gas evolution occurs. After a further 1 h the reaction mixture is poured slowly onto ice water (250 mL, gas evolution), and is extracted with ether (3×50 mL). The combined extracts are washed with water (2×100 mL) and saturated brine (100 mL) and dried (MgSO 4 ). The solvent is removed under reduced pressure to give 1-phenylcyclopropane carbonitrile (6.58 g, 92%) as a mobile brown oil. Nmr δ (CDCl 3 ) 7.25-7.40 (5H, m), 1.6-1.8, 1.2-1.45 (2H and 2H, AA'BB').
LiAlH 4 (1.8 g, 48 mmol) is added in batches over 5 min to a solution of 1-phenylcyclopropane carbonitrile (6.58 g, 46 mmol) in ether (200 mL) stirred under N 2 at 0°. After 1 h the reaction mixture is quenched by a careful dropwise addition of water (1.8 mL), 10% W/V NaOH solution (1.8 mL) and water (5.4 mL). Vigorous gas evolution again occurs. The mixture is vacuum filtered, and the filtrate is extracted with dilute HCl (0.2M, 3×100 mL). The combined extracts are washed with ether (3×100 mL) and made basic with NaOH pellets (3.2 g, 80 mmol). The aqueous layer is extracted with ether (3×100 mL). The combined organic phases are washed with water (2×100 mL), saturated brine (100 mL) and dried (MgSO 4 ). The solvent is removed under reduced pressure to give (1-phenylcyclopropyl)methylamine (4.98 g, 74%) as an orange oil. Nmr δ (CDCl 3 ) 7.1-7.5 (5H, m), 2.77 (2H, S), 1.3 (2H, br s), 0.6-0.95 (4H, m).
EXAMPLE 2
N6-((1-(3-Chlorophenyl)cyclopropyl)methyl)adenosine
(1-(3-Chlorophenyl)cyclopropyl)methylamine is prepared from (3-chlorophenyl)acetonitrile as described in Example 1.
Reaction of the above amine (1.82 g, 10 mmol) with 6-chloropurine riboside (2.87 g, 10 mmol) and triethylamine (2.02 g, 20 mmol) as described in Example 1 gives, N6-((1-(3-chlorophenyl)cyclopropyl)methyl)adenosine (3.42 g, 79%) as an off-white crystalline solid m.p. 71°-95°, in 74% overall yield. Found: C, 55.30; H, 5.05; N, 16.30; Cl, 8.15%. C 20 H 22 N 5 O 4 Cl calculated requires: C, 55.62; H, 5.10; N, 16.22; Cl, 8.23%.
EXAMPLE 3
N6-((1-Thien-2-ylcyclopropyl)methyl)adenosine
(1-Thien-2-ylcyclopropyl)methylamine is prepared from 2-thienyl acetonitrile and 1,2-dibromoethane as described in Example 1 in 57% overall yield.
Reaction of the above amine (1.53 g, 10 mmol) with 6-chloropurine riboside (2.87 g, 10 mmol) and triethylamine (2.02 g, 20 mmol) as described in Example 1 gives, after a second crystallization from ethanol, N6((1-thien-2-ylcyclopropyl)methyl)adenosine (2.90 g, 71%) as a fluffy off-white solid m.p. 136°-138.5° C. Found: C, 53.78; H, 5.45; N, 17.28; S, 7.52%. C 18 H 21 N 5 O 4 S calculated requires: C, 53.60; H, 5.21; N, 17.37; S, 7.94%.
EXAMPLE 4
N6-((1-Phenylcyclopropyl)methyl)adenosine-N1-oxide
m-Chloroperoxybenzoic acid (1.80 g, 85%, 9 mmol) and BHT stabilizer (0.20 g) in THF (10 mL) are added over 30 min to a solution of N6((1-phenylcyclopropyl)methyl)adenosine (1.19 g, 3 mmol), in refluxing tetrahydrofuran (THF) (5 mL). After a further 30 min the solvent is removed under reduced pressure, and the residue is purified by flash chromatography on silica gel, eluting with 7.5% then 15% CH 3 OH in CHCl 3 , then by preparative tlc on silica gel eluting once with 10% CH 3 OH in CHCl 3 . The major band r.f. 0.38 is extracted with CHCl 3 /CH 3 OH, and the solvent is removed rigorously under reduced pressure to give N6(1-phenylcyclopropyl)methyl)adenosine-N,1-oxide (0.48 g, 39%) as a white solid foam m.p. 105°-113° C. Found: C, 57.01, H, 5.55; N, 16.51%. C 20 H 23 N 5 O 5 calculated requires: C, 58.11; H, 5.57; N, 16.95%. IR 1647, 1579, 1502, 1214 cm -1 .
EXAMPLE 5
5'-Deoxy-5'-chloro-N6-((1-phenylcyclopropyl)methyl)adenosine
A solution of (1-phenylcyclopropyl)methylamine (0.55 g, 3.75 mmol), prepared as in Example 1, 6-chloropurine-5'-deoxy-5'-chlororiboside-2',3'-isopropylidene (1.25 g, 3.6 mmol) and triethylamine (0.75 g, 7.5 mmol) is refluxed in ethanol (40 ml) under N 2 for 24 h. The solvent is removed under reduced pressure and the brown gummy residue is partitioned between ethyl acetate (50 mL) and water (25 mL). The organic phase decanted and washed with water (25 mL), saturated brine (25 mL) and dried (MgSO 4 ). The solvent is removed under reduced pressure and the residual light brown oil is heated under N 2 in aqueous formic acid (50%, 20 mL) for 4 h. The solvent is removed under reduced pressure, and the residual light brown oil is heated under N 2 in aqueous formic acid (50%, 20 mL) for 4 h. The solvent is removed under reduced pressure, and the residue is dissolved in ethyl acetate (50 mL) and is washed with saturated NaHCO 3 solution (25 mL), water (25 mL), saturated brine (25 mL) and dried (MgSO 4 ). The solvent is removed under reduced pressure and the residual brown gummy foam is purified by preparative tlc on silica gel, eluting once with 10% CH 3 OH in CHCl 3 . The major band, r.f. 0.41, is extracted with CHCl 3 /MeOH, and the solvent is removed rigorously under reduced pressure to give 5'-deoxy-5'-chloro-N6-((1-phenylcyclopropyl)methyl)adenosine (0.40 g, 27%) as a pale khaki solid foam m.p. 73°-8° C. Found: C, 56.74; H, 5.20; N, 16.80; Cl, 9.13%. C 20 H 22 ClN 5 O 3 calculated requires: C, 57.76; H, 5.29; N, 16.85; Cl, 8.54%.
6-Chloropurine-5'-deoxy-5'-chlororiboside-2',3'-isopropylidene
Phosphorus oxychloride (12.28 g, 80 mmol) is added dropwise over 5 min to a stirred mixture of inosine-2',3'-isopropylidene (6.16 g, 20 mmol), tetraethylammonium chloride (6.60 g, 40 mmol), N,N-dimethylaniline (9.6 g, 80 mmol), and freshly powdered calcium hydride (0.52 g, 20 mmol) in acetonitrile (40 mL) under N 2 at 25°. After another 5 minutes the mixture is refluxed for 15 min. On cooling the volatiles are removed under reduced pressure, and the residual oil is diluted with CHCl 3 (200 mL) and poured onto a vigorously stirred mixture of 50% saturated Na 2 CO 3 soln (500 mL) and ice (250 mL). The organic phase is separated, and the aqueous phase is extracted with CHCl 3 (2×50 mL). The combined organic extracts are washed with saturated sodium carbonate solution (100 mL), and dried (Na 2 SO 4 ). The solvent is removed under reduced pressure and the residual oil is purified by chromatography on silica gel eluting with CHCl 3 , 2 then 4% CH 3 OH in CHCl 3 . The solvent is removed under reduced pressure to give 6-chloropurine-5'-deoxy-5'-chlororiboside-2',3'-isopropylidene (2.50 g, 36%) as an orange-brown gum. Nmr (CDCl 3 ) δ8.67 (1H, s), 8.25 (1H, s), 6.15 (1H, d, J=2.5 Hz), 5.33, 5.03 (1H and 1H, ABq of d, J AB =6 Hz, J d =2.5, 3 Hz), 4.46 (1H, d of t, J d =3 Hz, J t =6 Hz), 3.5-3.85 (2H, ABq of d, J AB =12 Hz, J d =6 Hz), 1.65 (3H, s), 1.41 (3H, s).
EXAMPLE 6
5'-Chloro-5'-deoxy-N6-((1-thien-2-ylcyclopropyl)methyl)adenosine
(1-Thien-2-ylcyclopropyl)methylamine (0.55 g, 3.6 mmol), see Example 3, 6-chloropurine-5'-deoxy-5'-chlororiboside-2',3'-isopropylidene (1.25 g, 3.6 mmol, as prepared in Example 5) and triethylamine (0.75 g, 7.5 mmol) are reacted together as described in Example 5. Aqueous formic acid hydrolysis gives 5'-chloro-5'-deoxy-N6-((1-thien-2-ylcyclopropyl)methyl)adenosine (0.44 g, 29%) as a light khaki solid foam m.p. 69°-75° C. Found: C, 50.53; H, 4.90; N, 15.90; Cl, 9.13; S, 7.22%. C 18 H 20 ClN 5 O 3 S calculated requires: C, 51.25; H, 4.74; N, 16.61; Cl, 8.42; S, 7.59%.
EXAMPLE 7
N6-((1-Phenylcyclobutyl)methyl)adenosine
(1-Phenylcyclobutyl)methylamine is prepared from phenylacetonitrile (2.93 g, 25 mmol) and 1,3-dibromopropane (7.57 g, 37.5 mmol) as described in Example 1 in 62% yield. The above amine (1.61 g, 10 mmol) is reacted with 6-chloropurine riboside (2.87 g, 10 mmol) as described in Example 1. As the compound did not crystallize it is purified by removal of the solvent under reduced pressure, followed by dissolving the residual gum in ethyl acetate (50 mL) and washing it with water (2×25 mL) and saturated brine (25 mL) and drying (MgSO 4 ). The solvent is removed under reduced pressure and the residual gum is subjected to flash chromatography on silica gel, eluting with 5% CH 3 OH in CHCl 3 . N6-((1-phenylcyclobutyl)methyl)adenosine (2.40 g, 58%) is obtained as a white solid foam m.p. 95°-118° C. Found: C, 61.21; H, 6.23; N, 17.24%. C 21 H 25 N 5 O 4 calculated requires: C, 61.31; H, 6.08; N, 17.03%.
EXAMPLE 8
N6-((1-(3-Chlorophenyl)cyclobutyl)methyl)adenosine
(1-(3-Chlorophenyl)cyclobutyl)methylamine is prepared from (3-chlorophenyl)acetonitrile (3.79 g, 25 mmol) and 1,3-dibromopropane (7.57 g, 375 mmol) as described in Example 1 in 60% overall yield.
The above amine (1.96 g, 10 mmol) is reacted with 6-chloropurine riboside (2.87 g, 10 mmol) and purified as described in Examples 1 and 7 above. N6-((1-(3-chlorophenyl)cyclobutyl)methyl)adenosine (3.66 g, 82%) as a pale yellow solid foam is obtained m.p. 92°-8° C. Found: C, 56.11; H, 5.33; N, 15.44; Cl, 8.99%. C 21 H 24 ClN 5 O 4 calculated requires: C, 56.57; H, 5.39; N, 15.71; Cl, 7.97%.
EXAMPLE 9
N6-((1-Thien-2-ylcyclobutyl)methyl)adenosine
(1-Thien-2-ylcyclobutyl)methylamine is prepared from thien-2-ylacetonitrile (3.70 g, 30 mmol), 1,3-dibromopropane (9.09 g, 45 mmol), as described in Example 1 in 55% yield.
The above amine (1.67 g, 10 mmol) is reacted with 6-chloropurine riboside (2.87 g, 10 mmol) as described in Example 1 and 7 is purified by column chromatography to give N6-(1-(thien-2-ylcyclobutyl)methyl)adenosine (3.18 g, 76%) as a colorless glass m.p. 84°-92° C. Found: C, 54.88; H, 5.69; N, 16.77; S, 7.55%. C 19 H 23 N 5 O 4 S calculated requires: C, 54.68; H, 5.52; N, 16.79; S, 7.67%.
EXAMPLE 10
N6-((1-Phenylcyclopentyl)methyl)adenosine
(1-Phenylcyclopentyl)methylamine is prepared as its hydrochloride salt, m.p. 185°-6° C. from 1-phenylcyclopentane carbonitrile as described in Example 11.
The above amine hydrochloride (5.0 g, 24 mmol) is reacted with 6-chloropurine riboside (6.8 g, 24 mmol) as described in Example 11 infra to give after column chromatography N6-((1-phenylcyclopentyl)methyl)adenosine (3.80 g, 37%) as a solid white foam m.p. 74°-8° C. Found: C, 59.02; H, 5.94; N, 15.25%. C 22 H 27 N 5 O 4 calculated requires: C, 62.12; H, 6.35; N, 16.47%. C 22 H 27 N 5 O 4 0.25 CHCl 3 requires C, 58.69; H, 6.03; N, 15.38%.
EXAMPLE 11
N6-((1-Phenylcyclohexyl)methyl)adenosine
(1-Phenylcyclohexyl)methylamine (1.80 g, 8 mmol) as prepared below, and 6-chloropurine riboside (2.36 g, 8 mmol) are reacted as described in Example 1. The solvent is removed under reduced pressure, and the residue dissolved up in CHCl 3 and washed with water and dried (MgSO 4 ). The solvent is removed under reduced pressure and the residual white foam is purified on silica gel chromatography eluting with 10% MeOH in CH 2 Cl 2 to give N6-((1-phenylcyclohexyl)methyl)adenosine (1.49 g, 42%) as a white glass m.p. 87°-9° C. Found: C, 62.22; H, 6.96; N, 15.70%. C 23 H 29 N 5 O 4 calculated requires: C, 62.87; H, 6.61; N, 15.95%.
(1-Phenylcyclohexyl)methylamine
1-Phenylcyclohexane carbonitrile is reduced with H 2 in methanol containing 16% ammonia with a Raney nickel catalyst. The catalyst is filtered off and (1-phenylcyclohexyl)methylamine is precipitated as its hydrochloride salt m.p. 230°-33° C., by treatment with methanolic HCl and isopropyl ether.
EXAMPLE 12
N6-((1-(4-Chlorophenyl)cyclopropyl)methyl)adenosine
(1-(4-Chlorophenyl)cyclopropyl)methylamine is prepared from 4-chlorophenyl acetonitrile and ethylene dibromide in overall 33% yield as described in Example 1.
Reaction of the above amine (1.48 g, 8 mmol) with 6-chloropurine riboside (2.09 g, 7.3 mmol) and triethylamine (1.1 mL, 8 mmol) as prepared in Example 1 and 7 gives N6-((1-(4-chlorophenyl)cyclopropyl)methyl)adenosine (1.47 g, 47%) as a cream colored solid m.p. 132°-8° C. Found: C, 56.16; H, 5.22; N, 15.54; Cl, 9.12%. C 20 H 22 N 5 O 4 Cl calculated requires: C, 55.62; H, 5.10; N, 16.22; Cl, 8.23%.
Also made by a process analogous to Example 1 were,
EXAMPLE 13 N6-(1-(4-Methoxyphenyl)cyclopropylmethyladenosine m.p. 88°-91° C.;
EXAMPLE 14 N6-(1-(3,4-Dichlorophenyl)cyclopropylmethyl)adenosine m.p. 120°-22° C.;
EXAMPLE 15 N6-(1-(2-methoxyphenyl)cyclopropylmethyl)adenosine m.p. 82°-90° C.;
EXAMPLE 16 N6-(1-Thien-3-yl)cyclopropylmethyl)adenosine m.p. 122°-7° C.;
EXAMPLE 17 N6-(1-(5-Bromothien-2-yl)cyclopropylmethyl)adenosine m.p. 112°-8° C.;
EXAMPLE 18 N6-(1-Naphth-2-ylcyclopropylmethyladenosine m.p. 91°-5° C.;
EXAMPLE 19 N6-(1-Naphth-2-ylcyclobutylmethyladenosine m.p. 110°-8° C.;
EXAMPLE 20 N6-(1-(2-Chlorophenyl)cyclopropylmethyl)adenosine m.p. 93°-101° C.
EXAMPLE 21 N6-(1-(2-Methylphenyl)cyclopropylmethyl)adenosine m.p. 95°-99° C.
EXAMPLE 22 N6-(1-(2-Furanyl)cyclopropylmethyl)adenosine m.p. 128°-30° C.
EXAMPLE 23 N6-(1-(5-Methylthien-2-yl)cyclopropylmethyl)adenosine m.p. 103°-106° C.
EXAMPLE 24 N6-(1-phenylcyclopropylmethyl)adenosin-5 1 -yl hydrogen succinate m.p. 143°-5° C.
EXAMPLE 25 N6-(1-phenylcyclopropylmethyl)adenosine-5 1 -uronamide m.p. 203°-5° C.
|
The present inventions are novel N 6 -substituted adenosines wherein the N substituent is ##STR1## wherein Ar is an unsubstituted or substituted (1) phenyl, (2) 1- or 2-naphthalenyl, (3) 2- or 3-thienyl, (4) 2- or 3-furanyl, (5) 2-, 4-, or 5-thiazyl, (6) 2-, 3-, or 4-pyridyl, or (7) 2-pyrimidyl wherein the substituents include at least one of lower alkyl, halo, trifluoromethyl, hydroxy, lower alkoxy, lower acyloxyamino, N-lower monoalkyl or N,N-lower dialkylamino, lower thioalkyl, lower alkylsulfonyl, or nitro and R' is hydrogen or alkyl, A is ##STR2## wherein q, q', or q" are one to four, n and m are independently zero to three provided if A is a bond then n and m is at least 2 and if A is other than a bond then n and m is at least one. These novel adenosines have highly desirable central nervous system and cardiovascular activities and therefore the present invention also includes pharmaceutical compositions and methods of use therefor.
| 2
|
RELATED APPLICATIONS
[0001] This application claims the benefit under 35 USC 119(e) of U.S. Provisional Application No. 61/011,473, filed on Jan. 17, 2008, which is incorporated herein by reference in its entirety.
BACKGROUND
[0002] 1. Technical Field
[0003] This invention relates to abrasive tools, and more particularly to grinding wheels having customizable grinding faces.
[0004] 2. Background Information
[0005] Abrasive tools such as grinding wheels are often customized for particular operations. For example, a grinding wheel may be provided with relatively large abrasive grains for rough grinding, or relatively small abrasive grains for precision grinding. A typical bonded abrasive grinding wheel is manufactured by mixing abrasive particles with a suitable bond matrix material (e.g., in liquid or powder form), which is then compressed in a mold to form a desired shape. This “green” form is then consolidated by sintering at a suitable temperature to form a unitary body having a plurality of abrasive particles dispersed uniformly therethrough.
[0006] Since the abrasive grains are integrated into the tool at an early stage in the production process, neither the tool nor the manufacturing line therefor, can be easily reconfigured for tools of differing sizes or abrasive/bond composition. Moreover, in part because separate tooling (e.g., wheel molds) is required for each wheel size, re-configuring conventional manufacturing lines tends to be labor intensive, often resulting in relatively long lead times. Provisions to increase coolant distribution or swarf removal, such as increasing porosity of the tool, require additional manufacturing steps generally associated with molding/sintering or finishing operations. These aspects typically result in a relatively expensive, multi-step fabrication process, having relatively long lead and process times, for each distinct tool configuration.
[0007] Therefore, a need exists for a tool and fabrication process therefor, which may be easily reconfigured for distinct sizes and abrasive/bond configurations.
SUMMARY
[0008] In one aspect of the invention, an abrasive grinding tool is provided with a backing plate, adapted to support abrasive segments in a plurality of positions over a majority of the surface area thereof, the backing plate also being configured to be secured to a grinding machine.
[0009] The abrasive segments and gaps between the segments may form a geometric pattern across all or a portion of the grinding side of the backing plate. The abrasive segments may be threadably secured, secured by adhesive resin (e.g., epoxy), or secured by any other suitable conventional means. The abrasive segments are available in a plurality of shapes and abrasive grain configurations. The sizes of the areas of the grinding surfaces of each of the abrasive segments may optionally be uniform.
[0010] In another aspect of the invention, the abrasive segments are removably secured and interchangeable. This allows the user to remove some segments and to replace them with segments of the desired formulation in the desired geometric pattern on the backing plate. This allows the backing plate to be reused after some abrasive segments have been worn.
[0011] In yet another aspect of this invention, a method of manufacture of an abrasive tool includes providing a backing plate configured to be mounted onto a grinding machine, providing abrasive segments, and mounting the segments onto a majority of the surface of the backing plate.
[0012] The above and other features of the invention including various details of construction and combinations of parts, and other advantages, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular method and device embodying the invention are shown by way of illustration and not as a limitation of the invention. The principles and features of this invention may be employed in various and numerous embodiments without departing from the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The above and other features and advantages of this invention will be more readily apparent from a reading of the following detailed description of various aspects of the invention taken in conjunction with the accompanying drawings, in which:
[0014] FIG. 1 is a plan view of an embodiment of the claimed invention;
[0015] FIG. 2A is a perspective, schematic view of the embodiment of FIG. 1 during a step of fabrication thereof;
[0016] FIG. 2B is a top plan view of the embodiment of FIG. 2A during a step of fabrication thereof;
[0017] FIG. 2C is a bottom plan view of the embodiment of FIG. 2A ;
[0018] FIG. 3 is a cross sectional view taken along 3 - 3 of FIG. 2A ;
[0019] FIG. 4 is a cross sectional view taken along 3 - 3 of FIG. 2A of an alternate embodiment of the invention;
[0020] FIGS. 5-6F are views similar to that of FIG. 1 of an alternate embodiments of the claimed invention;
[0021] FIG. 7A is a chart of an exemplary manufacturing process in accordance with the claimed invention;
[0022] FIG. 7B is a chart of a representative manufacturing process of a conventional grinding wheel;
[0023] FIG. 8 is a top plan view of a test wheel of the present invention prior to test grinding operations;
[0024] FIG. 9 is a view similar to that of FIG. 8 , of a control grinding wheel prior to test grinding operations;
[0025] FIG. 10 is a perspective view of the wheel of FIG. 8 during test grinding operations;
[0026] FIG. 11 is a perspective view of the control wheel of FIG. 9 during test grinding operations;
[0027] FIG. 12 is a top plan view of the embodiment of FIG. 8 after test grinding operations;
[0028] FIG. 13 is a top plan view of the control wheel of FIG. 9 after test grinding operations;
[0029] FIG. 14 is a graph of surface grinding efficiency versus wheel wear rate for the wheels of FIGS. 8 and 9 ;
[0030] FIG. 15 is a graph of unit power versus Material Removal Rate for the wheels of FIGS. 8 and 9 ;
[0031] FIG. 16 is a graph of Wheel Wear Rate versus Material Removal Rate for the wheels of FIGS. 8 and 9 ;
[0032] FIG. 17 is a graph of Unit Power versus Material Removal Rate for the wheels of FIGS. 8 and 9 ;
[0033] FIG. 18 is a graph of Wheel Wear Rate versus Material Removal Rate for the wheels of FIGS. 8 and 9 ;
[0034] FIG. 19 is a graph of Unit Power versus G-Ratio for the wheels of FIGS. 8 and 9 ; and
[0035] FIG. 20 is a graph of expected Unit Power versus expected Material Removal Rate for embodiments of the present invention.
[0036] FIG. 21 is a graph of Average Power versus G-ratio for several wheels according to embodiments of the invention and for control wheels.
[0037] FIG. 22 is a graph of G-Ratio versus MRR for several wheels according to embodiments of the invention and for control wheels.
[0038] FIG. 23 is a graph of Average Power versus MRR for several wheels according to embodiments of the invention and for control wheels.
[0039] FIG. 24 is a graph of Unit Power versus MRR for several wheels according to embodiments of the invention and for control wheels.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0040] In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration, specific 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. It is also to be understood that structural, procedural and system changes may be made without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims and their equivalents. For clarity of exposition, like features shown in the accompanying drawings shall be indicated with like reference numerals and similar features as shown in alternate embodiments in the drawings shall be indicated with similar reference numerals.
[0041] Where used in this disclosure, the term “axial” when used in connection with an element described herein, refers to a direction parallel to an axis of rotation of a grinding wheel onto which the element is installed. The term “transverse” refers to a direction substantially orthogonal to the axial direction.
[0042] As discussed above, conventional bonded abrasive grinding wheels are generally manufactured by mixing abrasive grains with a bonding material, molding and sintering the wheel, and attaching the tool onto a tool body or flange for engagement with a grinding machine. The instant invention represents a fundamental departure from such conventional manufacturing processes as it includes a tool which may be manufactured without being molded and sintering as a single unit. Instead, embodiments of the invention may be fabricated by assembling pre-manufactured abrasive segments in nominally any desired pattern on a backing plate to form a collective grinding face customized for any number of grinding applications. Thus, rather than relying on variations in abrasive/bond mixture and wheel diameter, etc., for customization during wheel fabrication, the instant invention enables the wheels to be customized simply by varying the selection (e.g., by grain type, composition), placement, and number of various segments.
[0043] In providing their simplified manufacturing approach, the instant inventors departed from conventional wisdom by increasing, rather than decreasing, the number of discrete components. Despite the increased number of components, relative simplicity was achieved by effectively moving product customization from the conventional abrasive/bond mixture and molding steps, to post-mold operations. In this manner, a wide range of customization may be provided using a relatively small number of discrete segment types, to advantageously simplify and streamline the molding and sintering processes, which processes tend to be relatively labor- and capital-intensive. For example, as described herein, segments of only a single size may be capable of producing grinding wheels having diameters ranging from 125 mm to 1200 mm or more. (Segments of various sizes, e.g., transverse and axial dimensions, may be used to further expand the range of possible wheel configurations. Indeed, embodiments having segments of at least two distinct sizes have been shown to provide a grinding wheel with desired grinding face area and product robustness in some applications.) This may effectively reduce process downtime associated with re-configuration of production lines for various product sizes, types, etc. This also tends to reduce product lead time, since the wheels may be assembled from inventoried segments, i.e., without the need to effect any mixing, molding, sintering, etc., at the time of wheel fabrication. So although the number of components within a specific tool may be relatively high, the number of distinct abrasive/bond combinations molded and sintered may be reduced, with variations in wheel size and composition handled post-mold, simply by varying the number and placement and/or type of segments.
[0044] Turning now to FIG. 1 , cylindrical abrasive segments 30 are secured to backing plate 20 to effectively form a grinding wheel 10 . The backing plate 20 is a disc which may be made of any material having the requisite structural integrity to secure the segments in position during a particular grinding operation, e.g., during rotation about its central axis at a rotational speed of several hundred rotations per minute (RPM) and surface feet per minute (SFPM) as discussed hereinbelow. Suitable materials may include reinforced polymeric materials such as glass reinforced polyester, and metallic materials such as various steels, cast iron, or various powdered metal constructions. Backing plate 20 may be fabricated in any desired manner, by use of conventional approaches such as molding, casting, machining, powder metallurgy, etc. The backing plate may be fabricated as a single component, or as a multi-component assembly.
[0045] The abrasive segments 30 may contain various types of abrasive grains known to those skilled in the art, such as alumina, alumina zirconia, silicon carbide, cubic boron nitride (CBN), diamond particles, and mixtures thereof. The segments may be fabricated from substantially any abrasive/bond combination known to those skilled in the art of grinding wheels, and/or which may be developed in the future. Examples of suitable abrasive/bond materials and mixtures, and fabrication techniques useful therefor, are disclosed in U.S. Pat. Nos. 5,658,360; 6,015,338; and 6,251,149; and U.S. Ser. No. 10/510,541, assigned to Saint-Gobain Abrasives, Inc., which are fully incorporated herein by reference.
[0046] As shown, the segments each have a grinding face 32 which collectively form a grinding face 22 of the wheel 10 . The grinding faces 32 of the segments may define mutually distinct surface areas, or alternatively, may define areas that are substantially uniform from segment to segment. Moreover, segments 30 may be removable, such as discussed hereinbelow, to be interchangeable with one another for replacement or to reconfigure a wheel for different grinding application.
[0047] Turning now to FIG. 2A , abrasive segments 30 may be fastened to backing plate 20 in any convenient manner, such as by engagement with suitably sized and shaped mounts 40 , such as in the form of surfaces or cavities disposed along side 24 of backing plate 20 to which segments may be bonded or inserted. Internal threads 60 may be drilled, molded or otherwise disposed in side 26 of plate 20 for securing the wheel 110 to a grinding machine.
[0048] Turning now to FIG. 2B , segments having nominally any transverse shape may be fastened to backing plate 20 , to provide a wide variety of collective grinding face patterns. As shown, examples of such multi-shaped segments include cylindrical segments 30 , wedge shaped segments 130 , hexagonal segments 230 , diamond shaped segments 330 , and complex segments 430 . The particular segment shape may be chosen based on its suitability for a particular grinding application. For example, cylindrical segments 30 having relatively large size abrasive, may be used for rough grinding, while hexagonal pellets 230 having relatively small size abrasive may be used for fine grinding. The spacing between segments may also be customized for particular operations. Wider spacing, for example, may be desired in some rough grinding applications to facilitate swarf removal.
[0049] In addition to the distinct sizes and shapes shown, abrasive segments 30 , 130 , 230 , and 330 may also have distinct abrasive and bond compositions. For example, cylindrical segments 30 may have larger abrasive particulates for rough grinding, and diamond shaped abrasive segments may have smaller abrasive particulates for precision grinding. The segments may be color coded to the various compositions thereof, such as by including a pigment with the abrasive/bond mixture, to enable users to easily distinguish between segments that are otherwise similar in appearance.
[0050] As also shown, the abrasive segments and the gaps formed between them may be arranged to form a collective grinding face 22 having a geometric pattern. The particular geometric pattern may be chosen based on the needs of particular operations. For example, patterns providing for a relatively large network of gaps 42 between segment grinding faces 32 , 132 , 232 , 332 , 432 may facilitate distribution of coolant and other grinding aids, and the removal of debris such as grinding swarf. These gaps 42 may thus reduce the need for adding porosity to the abrasive/bond mixture to further simplify the molding/sintering operations.
[0051] As mentioned hereinabove, substantially any geometric pattern formed by abrasive segments and spaces between the segments, may be used. For example, the embodiment of FIG. 5 includes diamond shaped abrasive segments 330 . Additional exemplary patterns are shown in FIGS. 6A-6F . The embodiment of FIG. 6A includes a pattern formed with cylindrical abrasive segments 30 of uniform size, while the embodiments of FIGS. 6B and 6F include cylindrical abrasive segments 30 , 34 , 36 , 38 of varying sizes. As shown in FIG. 6C , alternate embodiments may include patterns formed by wedge shaped segments 130 of varying sizes, with gaps 142 therebetween. A pattern formed by diamond shaped segments 330 with gaps 342 is shown in FIG. 6D , while a pattern formed by hexagonal shaped segments 230 and gaps 242 is shown in FIG. 6E .
[0052] Referring now to FIG. 2C , backing plate 20 may be provided with an array of threaded fastener portions 60 (e.g., threaded bores, as shown) forming any number of patterns suitable for fastening the wheel 200 to a tool such as a grinding machine. The threaded bores 60 may be provided by any suitable means, such as drilling and tapping, molding into the backing plate, or by molding threaded inserts in-situ within the plate.
[0053] Abrasive segments 30 , 130 , 230 , etc., may be fastened to backing plate 20 in any convenient manner. For example, as shown in FIG. 3 , the segments may be threadably fastened to side 24 of backing plate 20 ( FIG. 2A ) using a threaded mandrel 44 . Any suitable means for fastening mandrel 44 to the abrasive segment 30 may be used.
[0054] As shown, mandrel 44 may be threadably received within a segment backing plate 50 . Alternatively, mandrel 44 may be molded in place within abrasive segment 30 during fabrication thereof, such as in the event segment backing plate 50 is not used. Still further, mandrel 44 may be glued or otherwise secured within a bore in abrasive segment 30 , using an epoxy or other suitable adhesive.
[0055] Turning now to FIG. 4 , as a further alternative, segment backing plate 50 ′ may include a threaded insert 46 which is molded in-situ within the segment during fabrication thereof. Alternatively, threaded insert 46 may be cemented with epoxy, or otherwise bonded within a suitably sized and shaped recess within abrasive segment 30 . The insert 46 may threadably engage a mandrel 44 such as shown in FIG. 3 .
[0056] As shown in FIGS. 7A and 7B , an exemplary manufacturing process ( FIG. 7A ) for embodiments of the present invention includes fewer steps than a typical manufacturing process associated with conventional grinding wheels ( FIG. 7B ). Moreover, various manufacturing steps shown in FIG. 7A may be automated for further simplification and associated cost savings. For example, filling of segment molds may be effected automatically using a conventional volumetric automatic press. Assembly of the various segments onto the back plate may also be automated, e.g., using conventional robotic assembly means such as commonly used in automobile assembly plants and the like. Moreover, as discussed hereinabove, because the various segments may be pre-fabricated and stored in inventory, assembly of the segments onto the back plates may be performed on-demand, e.g., to reduce manufacturing assembly/lead time.
[0057] Optional aspects of the exemplary manufacturing process include the reduction or elimination of many finishing steps. For example, any need for discrete segment leveling steps after wheel fabrication may be reduced by arranging the segments with their grinding faces against a planar surface, and then gluing the plate onto the back of the segments. The planar surface would nominally ensure that all of the segment faces are co-planar. Other conventional finishing steps, such as the drilling of holes in the wheel for swarf removal may also be eliminated, due to the existence of gaps 42 between the segments.
[0058] The following illustrative example is intended to demonstrate certain aspects of the present invention. It is to be understood that this example should not be construed as limiting.
Example I
[0059] An experimental grinding wheel 10 was fabricated substantially as shown and described hereinabove with respect to FIG. 8 , including 38 cylindrical segments 30 spaced along a backing plate 20 having a 5 in (12.7 cm) diameter. The abrasive segments 30 were produced using a manual arbor press, having uniform dimensions of approximately ⅝ in (1.59 cm) diameter and approximately ⅝ in (1.59 cm) (axial) depth. The abrasive segments 30 were fastened to the back plate 20 using standard plate mount 2 part epoxy (Epoweld® epoxy 13230 part A & B, from Royal Adhesives and Sealants, LLC, South Bend Ind.). The total contact area of the collective grinding face 22 (i.e., the total contact area of contact between the mosaic wheel and the workpiece) was 15.48 cm2.
[0060] The wheel 10 was tested and compared with a conventional 5 inch (control) grinding wheel 12 , as shown in FIG. 9 . Both the standard wheel 12 and the abrasive segments 30 of the mosaic wheel 10 were formulated in accordance with the 38A80 (3948) (i.e., semi friable white agglomerated Alundum)/80 grit size—E14 (Porosity/Abrasive vol.) B493 Bond (65% 29-717 phenolic resin and 35% Calcium Fluoride (CaF2) Vortex specification, as shown in the following Table I. The contact area of the standard wheel 12 was 106.45 cm2.
[0000]
TABLE I
T361 Grade (Bond) E-14 Abr. rho 3.95<
Agglom-
Wa
0.974
rho g
Va
0.9579
Aion rho
erate
Wg
0.026
2.4
Vg
0.0421
4.055
1.000
1.000
Porosity
Abrasive
(vol.)
(vol.)
B
0.50
17
0.30
Va
0.36<
C
0.48
16
0.32
Vb
0.20
D
0.46
15
0.34
Vp
0.44<
E
0.44
14
0.36
1.00
F
0.42
13
0.38
G
0.40
12
0.40
H
0.38
11
0.42
@increase lpr-1 level if mix is dusty
I
0.36
9
0.46
@go to 76 standard bake if wheels/slugs slump
J
0.34
K
0.32
L
0.30
Slug wt. 9.1 g
M
0.28
resin > 65.00
filler (60/40) 35
bond rho 1.945
added bond
Adj
mix
0.1842 vol
resin
Adj
size
Mix
fract in 1 cc,
factor
wt %
200 g
weights
Cummulative
agg
1.460
0.8030
x1.00
0.803
x200
160.60
3948-80
resin
0.153
0.0843
x0.23
0.0194
x200
3.88
Lpr-1
164.48
x0.77
0.0649
x200
12.98
t361
{close oversize brace}
35.52
filler
0.205
0.1127
x1.00
0.1127
x200
22.54
CaF2
1.818
200.00 g
200.00 g
[0061] The experimental and control wheels were tested under the following conditions:
[0062] Machine: Track Grinder Disc Simulation
[0063] Material: 1070
[0064] Work Speed: 3 RPM
[0065] Wheel Speed: 4202 RPM; 5500 SFPM (Surface Feet Per Minute)
[0066] In Feed Rates: 0.002, 0.0027, 0.004 in/rev.
[0067] MRR (Material Removal Rates): 0.67, 0.90, 1.34 in 3 /min./in 2
[0068] To ensure that the segments had the mechanical properties sufficient to withstand the centrifugal forces during the test conditions, the following assumptions and calculations were made:
[0069] centrifugal force acts as a single force at the tip of the segment
[0070] the segment is modeled as a cylindrical cantilever beam
[0071] maximum strength is 80% of the average mechanical strength
[0072] The following equations were used to estimate the stress on a single segment on the OD of the wheel where maximum stress is encountered:
[0000]
Force
centrifugal
(
N
)
=
[
(
Mass
of
segment
in
Kg
*
(
Velocity
of
segment
in
m
/
s
)
2
]
(
radius
of
disc
in
m
)
Equation
1
Stress
[
on
segment
]
(
MPa
)
=
[
(
Force
centrifugal
in
N
)
*
(
L
[
length
]
in
mm
)
]
[
(
∏
/
4
)
*
(
radius
in
mm
)
3
]
Equation
2
[0073] The following Table II provides examples of the calculations used to estimate the required sizes of the segments and backing plates for testing.
[0000]
TABLE II
Sm
Max strength
9.6
MPa
v
Wheel Speed
48.5
m/s
plug density
1.85
g/cc
Rw
radius, wheel
m
Rp
radius, plug
mm
L
length, plug
mm
m
mass
kg
radius,
wheel
Rp
L
Mass
Fcent
Stress
in
m
mm
mm
kg
(N)
(MPa)
Failure ?
6
0.1524
7.9
25.4
0.0093
143.2
9.3
No
6
0.1524
7.9
20.3
0.0074
114.6
5.9
No
6
0.1524
7.9
17.0
0.0062
95.9
4.2
No
6
0.1524
7.9
12.7
0.0046
71.6
2.3
No
30
0.762
7.9
76.2
0.0279
85.9
16.7
Yes
30
0.762
19.1
101.6
0.2142
659.8
12.4
Yes
30
0.762
25.4
101.6
0.3808
1173.0
9.3
Yes
6
0.1524
12.7
25.4
0.0238
366.6
5.8
No
[0074] Advantages of the empty gaps between the abrasive segments became apparent during and after testing. During the grinding test it was observed that the two wheels distribute coolant differently. As shown in FIG. 10 , the mosaic wheel 10 distributed coolant more evenly than the standard wheel 12 shown in FIG. 11 . After the grinding operation, the standard wheel 12 had swarf in the grinding area ( FIG. 13 ). The mosaic wheel 10 had grinding swarf trapped in the gaps between the segments, and a small amount of swarf on the grinding contact area ( FIG. 12 ).
[0075] A graph was developed ( FIG. 14 ) comparing Wheel Wear Rate and Surface Grinding Efficiency. This graph does not take into account that the mosaic wheel 10 is drawing less power, cutting at a lower material removal rate, and has 30% less workpiece contact area than the standard 12 . Notwithstanding these qualifications, the graph of FIG. 14 shows that the mosaic wheel 10 has a slightly better cutting efficiency and is somewhat more durable than the standard wheel 10 .
[0076] When comparing unit power plotted against the material removal rate (MRR), the performances of the mosaic wheel and the standard wheel were approximately equal. ( FIG. 15 ). The performances of the mosaic wheel and the standard wheel were also approximately equal when Wheel Wear Rate (WWR) was plotted against the MRR. ( FIG. 16 ). At a particular MRR, the mosaic wheel has higher wheel wear and shorter life, likely due to the lower abrasive volume of the wheel relative to the control wheel. ( FIGS. 17 , 18 ).
[0077] As seen in the graph of FIG. 19 , the mosaic wheel appears to operate as efficiently as the standard wheel, except at higher MRRs, where the exemplary wheel exhibits a slightly lower G—ratio (the ratio of work material to wheel material removed during grinding), and draws more power than the control wheel. As seen in the graph of FIG. 20 , performance of the mosaic wheel may be improved as the proportion of resin content is increased. Increased resin content may also advantageously improve mechanical strength, as can be seen in Table III. It is also expected that the use of various conventional fillers may be desired in some applications to improve MMR and reduce power consumption.
[0000]
TABLE III
Mosaic wheel
Mechanical Properties
content
Dry (MPa)
Wet (MPa)
100% resin
24
20
80/20 resin/filler
18.3
13
60/40 resin/filler
11.1
8.2
[0078] It is estimated that the experimental wheel may be manufactured at a material cost savings of approximately 12 percent, a labor cost reduction of about 70 percent, a process time reduction of about 80 percent, and a lead time reduction of about 75 percent relative to the control wheel.
Example II
[0079] Experimental grinding wheels, otherwise similar to those of Example I, were fabricated with the segment pattern shown in FIG. 6B , to provide a collective grinding face of relatively increased surface area. As shown, these wheels each included twenty one cylindrical segments 30 , 34 spaced along a backing plate 20 of 5 in (12.7 cm) diameter. Each wheel was provided with segments of the following quantity and dimensions.
[0000]
No. of segments
Diameter
Axial Depth
per wheel
in. (cm)
in. (cm)
14
1 (2.54)
0.750 (1.9)
7
0.750 (1.9)
0.750 (1.9)
[0080] The segments were formulated substantially as described in Example I, using phenolic and epoxy resins (Durez Varcum® phenolic resin 29-717, Durez Corporation, Dallas Tex., and Araldite® epoxy resin, Huntsman Advanced Materials Americas Inc., Brewster, N.Y.). The segments were fabricated in the following structure and grade series (Table I) and resin/filler amounts.
[0000]
Structure
Grades
Resin/Filler
14 (36%
H-I-J
Phenolic (29-717) 65/35 CaF2
abrasive)
14
G-H-I
Phenolic (29-717) 80/20 CaF2
14
E-F
Epoxy (Araldite 6004) 70/30 CaF2
[0081] The segments were molded in a multi cavity mold capable of producing 12 segments, (6 of each size). Epoxy segments were baked in the mold: oven preheated to 75° C.; Soak for 1 hour; Ramp to 100° C. and soak for 2 hours.
[0082] The wheels were tested and compared with conventional 5 inch vortex (control) grinding wheels 12 , as used in Example I, and with a similar control wheel fabricated as a conventional L9 (i.e., 30% porosity, 46 wt. % abrasive, Table I) B18 Bond (Saint-Gobain Abrasives, Inc., Worcester, Mass.).
[0083] Test results are shown in FIGS. 21 to 24 . Referring to FIG. 21 , the inventive 80/20 phenolic wheels and the epoxy wheels exhibited higher G—Ratios at higher power consumption than both control wheels. The 65/35 phenolic wheels reached nominal parity with the vortex control wheel at I grade, with comparable power consumption and a small increase in MRR. As shown in FIG. 22 , the epoxy mosaic wheel exhibited a significant increase in G—ratio over the vortex control wheel. As shown in FIGS. 23 and 24 , both phenolic wheels and the epoxy wheel nominally met or exceeded the MRR of vortex control wheels in many instances.
[0084] The inventive wheels of Example II have therefore been shown to be suitable for many disc grinding applications, particularly those requiring a relatively high MRR.
[0085] The foregoing demonstrates that the grinding wheels of the invention perform comparably, if not better, than conventional grinding wheels, while providing the advantages of a streamlined, less expensive manufacturing process with the capability of relatively simple wheel customization and production line changeover for significantly reduced lead time and manufacturing time. Moreover, in many embodiments, the backing plate may be re-used by simply replacing worn segments with new ones.
[0086] In the preceding specification, the invention has been described with reference to specific exemplary embodiments thereof. It will be evident that various modifications and changes may be made thereunto without departing from the broader spirit and 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.
[0087] While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.
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An abrasive tool includes a back plate with a first side and a second side, a plurality of segment mounts disposed in spaced relation along a majority of said first side, a plurality of abrasive segments engaged by the segment mounts, the second side being configured for attachment to a grinding machine. A method of manufacture of an abrasive tool includes providing a backing plate configured to be mounted onto a grinding machine, providing abrasive segments, and mounting the segments onto a majority of the surface of the backing plate.
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BACKGROUND OF THE INVENTION
The present invention relates to a load-carrying rescue hook assembly intended to function at the end of a cable or rope, which is raised by a hoisting apparatus. The hook carries a load, which is typically attached to the hook in the form of a sling or similar attachment strap.
Known hook assemblies of this type comprise a hook member designed to carry a sling or similar load-bearing attachment strap. The sling or attachment strap is engaged to or disengaged from the load-bearing portion of the hook through a gap provided between one side of the hook and an opposed tip portion of the hook. For safety, a gate or latch of some type typically bridges this gap. In most cases, this gate is pivotally attached to the side of the hook opposite its tip and is spring loaded in such a manner that the gate is biased into the closed position to prevent accidental disengagement of the sling or strap.
Known hook assemblies of the above-mentioned type have considerable disadvantages. For instance, the spring used in the spring-loaded gate has a finite size constraint due to the dimensions of the hook and gate. This size constraint, in turn, limits the maximum allowable spring rate. At times when this type of hook is lifting a load, the load may oscillate a considerable amount. Though rare, these oscillations may cause the portion of the sling or attachment strap that is inside the hook to come into contact with the gate, overcome the spring force of the gate, and cause an accidental disengagement of the load in what is commonly referred to as “roll-out”. In addition, if the gate is snagged by anything during use and the spring force is overcome, the gate can open. Thus, there is a potential for either an accidental disengagement of the load or accidental engagement of whatever snagged the gate.
To address the disadvantages caused by an accidental gate opening, some hooks employ a mechanism that locks the gate into the closed position in conjunction with spring-loaded retention. Operation of these gates usually involves a two-step operation, where the first step is to unlock a locking mechanism and the second step is to open the spring-loaded gate. When the gate is allowed to return to the closed position, the locking mechanism is automatically engaged and the process must be repeated in order to open the gate again.
Known hook assemblies that incorporate a locking mechanism are often difficult and cumbersome to operate. Because the operator of a rescue hook will often be wearing gloves, and because the hook may be used in adverse conditions such as cold weather, at night, in water, or a combination of the three, a two-step locking mechanism operation has proven to be difficult and can cost valuable time during a rescue operation. In addition, this operation must be repeated each time the gate needs to be opened, thereby increasing the number of times this difficulty must be overcome. Moreover, the locking mechanism of known hook assembles often requires a level of manual or digital dexterity that an operator may not possess when his or her hands are cold.
It is an object of this invention to provide a rescue hook assembly that utilizes a spring-loaded gate in conjunction with a locking safety mechanism to prevent accidental gate opening.
It is another object of this invention to provide such a locking safety mechanism that can be toggled from the “locked” to “unlocked” position or vice versa easily and with one motion, and that will remain in the “locked” or “unlocked” position as long as may be desired.
It is a further object of this invention to provide a locking safety mechanism that can be operated without requiring a high level of digital dexterity.
In particular, this invention provides a locking safety mechanism that operates separately from the spring-loaded gate, thus allowing the gate to be opened and closed numerous times while the locking mechanism is in the “unlocked” position, while not allowing the gate to open while the locking mechanism is in the “locked” position.
Further objects and advantages of the invention are set forth below or are apparent to those skilled in the art.
SUMMARY OF THE INVENTION
With these objectives in mind, the present invention provides a rescue hook assembly with a safety locking mechanism. The rescue hook is suited for, inter alia, helicopter search and rescue (SAR) operations. The rescue hook is comprised of a hook body having a curved, inner load-bearing surface at its lower portion and an attachment stem at its upper portion for attachment to a cable or rope of a hoisting apparatus.
An opening or gap into the curved, load-bearing surface is defined by a space between the hook's tip end and the hook body opposite the hook tip. This gap allows the introduction of items into the load-bearing section of the hook body.
A spring-loaded gate is pivotally attached to the hook body and bridges the gap, and is biased by a spring towards the hook tip, thereby keeping the gap closed. The gate can be opened by applying pressure on the gate towards the hook body, and the gate will return to the closed position when the pressure is removed (e.g., when a load or sling is “snapped” into the hook). In order to keep the gate in the closed position when unwanted pressure might attempt to open the gate, this invention incorporates a safety mechanism. A sliding latch mechanism saddles the edge of the hook body and is located in such a way that it prevents the gate from opening when in a locking position.
The latch has two distinct positions: locked and unlocked. Each position is defined by the mating of the spring-loaded ball of a ball-detent plunger with an indentation on the inside face of the latch. When the indentation of the latch is mated with the ball-detent that corresponds to the locked position, the latch prevents the gate from opening even when pressure is applied to the gate. By applying pressure to the latch and sliding it, the latch moves away from the locked position until the indentation is mated with the ball-detent corresponding to the unlocked position. The gate is then allowed to freely open and close until the operator moves the latch back to the locked position.
Red and green pins made from fiber optic material or other suitable plastic are located in the hook body in such a manner that when the latch is in the locked position, the green pin is visible and the red is not. Likewise, when the latch is in the unlocked position, the red pin is visible and the green is not. The combination of the latch mechanism that can be easily moved between the locked and unlocked position along with color-coded indicators makes this rescue hook easy to operate with very little training.
BRIEF DESCRIPTION OF THE DRAWINGS
The attached drawings form a part of this specification, and reference numbers used in the drawings correspond to reference numbers contained in the written description:
FIG. 1 is an isometric, exploded view of a preferred embodiment of the Rescue Hook of the invention.
FIG. 2 is a front view of a preferred embodiment of the Rescue Hook with the gate closed and the latch in the locked position.
FIG. 3 is a front view of a preferred embodiment of the Rescue Hook with the latch in the unlocked position and the gate open.
FIG. 3 a is a front view of a preferred embodiment of the Rescue Hook with the latch in the unlocked position, the gate closed, and showing a load sling in place.
FIG. 4 is an isometric view of the body of a preferred embodiment of the Rescue Hook.
FIG. 5 is an isometric view of a ball-detent plunger (3× scale of FIG. 4 ).
FIG. 6 is an isometric view of a latch (2× scale of FIG. 4 ).
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The Rescue Hook has a hook body 10 with a curved, lower inside edge 11 and an opening (hereafter referred to as gap) 12 between the hook tip 13 and the upper inside edge 14 of said hook body. A threaded attachment stem 15 is located at the top of said hook body 10 and serves as an attachment to mate with a hoisting apparatus, connecting swivel or other connecting device. The particular means by which the Rescue Hook is mated with a line connecting it to a hoist is not part of the invention, however. As persons skilled in the art will recognize, other attachment methods would also be possible. A multi-purpose hole 16 located at the bottom of the hook can serve as an attachment location for an accessory or safety line.
Gap 12 is bridged by a triangular-shaped gate 17 , which gate is pivotally attached to said hook body 10 by means of a rivet style fastener 18 or similar fastening device. As shown in FIG. 1, gate 17 comprises two essentially triangular plates 17 a and 17 b which are joined on one side by side 22 a . Fastener 18 passes through holes 19 bored through two opposing sides 17 a and 17 b of gate 17 at its upper end and also passes through holes 20 bored through two ears 21 that extend from hook body 10 . A cut-out 22 in the lower portion of the side 22 a of gate 17 allows gate 17 to cover a portion of hook tip 13 . The upper edge of cut-out 22 (i.e., the lower edge of side 22 a ) makes contact with hook tip 13 and serves to limit the rotation of gate 17 away from hook body 10 .
A torsion spring 23 is located between ears 21 and serves to bias gate 17 toward hook tip 13 . When the Rescue Hook is assembled, torsion spring 23 rests between ears 21 ; fastener 18 passes through the coil portion of torsion spring 23 . One distal end 23 a of torsion spring 23 rests against the inside face of side 22 a of gate 17 , while the other distal end 23 b of torsion spring 23 rests against the portion of hook body 10 between ears 21 . Gate 17 has two operating positions: closed and open. In the closed position (as shown in FIG. 2 with side 22 a shown with hidden lines), the upper edge of cut-out 22 is held against hook tip 13 by the force of torsion spring 23 . In the open position (as shown in FIG. 3 ), gate 17 is rotated toward the main portion of hook body 10 .
In order to maintain gate 17 in the closed position when so desired, this invention incorporates a safety locking mechanism in the form of a latch 24 . Said latch 24 is in the form of a saddle that is slidably attached to said hook body 10 by means of two protruding rails 25 on the opposing inside faces of latch 24 . Rails 25 mate with two grooves 26 , which grooves are cut into opposing sides of hook body 10 and are parallel with the upper outside edge 27 of hook body 10 .
The amount by which latch 24 may travel along grooves 26 is limited by an upper stop-pin 28 and a lower stop-pin 29 . Upper stop-pin 28 is placed through a hole 30 bored through hook body 10 at the upper end of grooves 26 . Lower stop-pin 29 is placed through a hole 31 bored through hook body 10 at a point along grooves 26 approximately 1.25 inches below the centerline of upper stop-pin 28 . The ends of stop pins 28 and 29 are flush with the sides of hook body 10 , but form obstructions within grooves 26 that restrict the extent to which latch 24 may slide in said grooves.
Within its range of sliding motion, latch 24 is held in two distinct positions with the aid of a threaded, upper ball-detent plunger 32 and a threaded, lower ball-detent plunger 33 . Such pre-formed ball-detent plungers are well known in the art. Such ball-detent plungers, an outer view of which is shown in FIG. 5, generally comprise a threaded outer body portion encasing a spring and ball, with the ball biased by the spring through an opening in one end of the ball-detent plunger. Such a ball-detent plunger is available from McMaster-Carr Supply Company, part no. 340A95. Upper ball-detent plunger 32 is threaded into a tapped hole 34 bored through hook body 10 in an area between grooves 26 and upper outside edge 27 of hook body 10 . In a similar manner, lower ball-detent plunger 33 is threaded into a tapped hole 35 bored through said hook body 10 approximately 0.45 inches below the centerline of upper ball-detent plunger hole 34 in a direction parallel to grooves 26 .
A small indentation 36 on the inside face of said latch 24 is designed to mate with the spring-loaded ball 37 of ball-detent plungers 32 and 33 . When indentation 36 is mated with said spring-loaded ball 37 of upper ball-detent plunger 32 , latch 24 is in the locked position (as shown in FIG. 2 ). In this position, the lower edges of latch 24 prevent gate 17 from rotating to the open position. When indentation 36 is mated with the spring-loaded ball 37 of lower ball-detent plunger 33 , latch 24 is in the unlocked position (as shown in FIG. 3 ). In this position, gate 17 is free to rotate between the open and closed positions. The spring-loaded force of the balls 37 of ball-detent plungers 32 and 33 serve to retain latch 24 in the locked and unlocked positions, respectively. Said spring forces can be overcome, however, by exerting a moderate sliding force on latch 24 in directions A (FIG. 2) and B (FIG. 3 a ). Ease of moving latch 24 from the locked position to the unlocked position and vice versa is enhanced by the addition of grippers 38 formed into the sides of latch 24 . The configuration of a sliding latch allows an operator to lock or unlock the Rescue Hook, even if the operator's fingers are cold and/or numb, by moving latch 24 with the palm of the hand.
Indentation 36 on the inside face of latch 24 can be created by boring a hole 39 through the opposite side of latch 24 and then using the tip of the drill to create indentation 36 in a procedure commonly referred to as “spot facing”. Hole 39 also allows access to ball-detent plungers 32 and 33 . This access allows the tension of the ball-detent plungers 32 and 33 to be adjusted while mated with indentation 36 .
Persons skilled in the art will recognize that numerous alternative means may be employed to retain latch 24 in its locked and unlocked positions, the use of ball-detent plungers being merely the preferred embodiment. By way of example only, a spring-loaded cam-type follower could be adapted to an inside portion of latch 24 and configured to rest in depressions formed on body 10 .
To facilitate ease of use by less skilled operators, this invention further includes colored pins made from fiber-optic material, plastic or other suitable material, and that indicate whether latch 24 is in the locked or unlocked position. Preferably, a red pin 40 is placed through a hole 41 bored through hook body 10 inside said grooves 26 just below upper stop pin 28 . When latch 24 is in the unlocked position, red pin 40 is visible, indicating this position as unsafe. A green pin 42 is placed through a hole 43 bored through hook body 10 inside grooves 26 just above lower stop pin 29 . When latch 24 is in the locked position, green pin 42 is visible, indicating this position as safe. The ends of both pins 40 and 42 are flush with the bottoms of grooves 26 , thereby not interfering with the motion of latch 24 .
Hook body 10 , gate 17 and latch 24 can be made from any material or materials that will provide the strength and corrosion-resistance properties needed for a particular application. Possible materials include 15-5PH or 17-4PH stainless steel.
The foregoing description is of a preferred embodiment of the Rescue Hook, and is intended to instruct those skilled in the art how to make and use the invention. Such persons will appreciate, however, that there are many possible variations and modifications to the above-described embodiment of the invention. The invention is not limited by the preferred embodiment, but instead includes all modifications, variations and equivalents, and is limited only by the attached claims, which claims are to be given the widest scope consistent with the principles disclosed and as may be allowed by the prior art.
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This invention relates to a rescue hook assembly that utilizes a spring-loaded gate across the opening into the hook and has an improved safety locking mechanism to prevent accidental opening of the gate. The locking mechanism works independently from the gate, thus allowing the gate itself to be opened and closed multiple times while the locking mechanism is disengaged. With the locking mechanism engaged, however, the gate is kept in its closed position. The locking mechanism can be operated with one hand and color-coded indicators let the operator know if the mechanism is in the locked or unlocked position.
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CROSS-REFERENCES
[0001] This application claims the priority of provisional application: 61/476,382 filed on Apr. 4, 2011 by inventor Robert G. Marcotte entitled: “Comprehensive Wellness Tracking System”
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention contained herein pertains to the field of networked information systems and in particular to a system for centralizing an individual's personal information such that the individual has ownership of and systematically receives personal information gathered by institutional parties.
[0004] 2. Description of the Related Art
[0005] Medical, financial, civil and retail institutions maintain records for individuals. Record ownership resides with the institutional party. The individual party, to whom these records pertain, is isolated from the information management process and unable to control records within the public domain.
[0006] Medical records are distributed across the industry and systematically destroyed. Systematic tracking of health records within families and lifetimes is nonexistent. Public health costs are high due to repetitive testing and a lack of early detection.
[0007] Application software, and in particular, office automation systems provide institutions with platforms for managing the operations within the institution and for gathering and maintaining the records of individuals. Cross institutional access to information is limited to nonexistent.
[0008] Aspects of financial information related to individuals is routinely transmitted between financial institutions for maintaining credit ratings. Likewise, insurance companies transmit records to civil agencies pertaining to automotive insurance coverage. Insurance companies also systematically receive claims electronically from medical institutions including private practices.
[0009] Information transport and storage systems routinely pass information across secure and insecure information networks. File transfer protocol (FTP) provides a method for accessing a remote information storage area across a network, henceforth referred to as an FTP destination. Remote procedure calls (RPC) offer a second protocol for transferring information across networked locations.
[0010] Each protocol shall now be described in detail. With FTP, a first party has file ownership rights to an FTP destination. The FTP destination hardware (computers, disk drives, network interfaces) is typically hosted (i.e. physically owned) by a second party. Hosting application software provides the first party with a means for generating usernames and passwords for allowing access to their FTP destination area. Using the host application software, the first party creates an account identifier, i.e. a username and password, and provides the FTP destination and account identifier to a third party. The third party accesses the network location of the first party and, after providing the FTP password, has access to the information storage area. Once the third party moves a file into the first party's information storage area, the first party attains ownership of the file and has full control over the file. That is, the first party can delete, modify, archive, or share the file received.
[0011] The FTP protocol is commonly used for website development and for transferring large engineering documents between designers and manufacturers. Application software for website development stores the FTP destination and password within the configuration tables of the website being created. As the developer builds the website, FTP provides a link between the application software and the FTP destination.
[0012] RPC's offer a simpler interface between sophisticated websites. With an RPC, a first website can poll a second website for selective information. That is, the first website prepares an information request record, and sends the record to the second website. The second website receives the information request and returns the information requested to the first website as a reply record.
[0013] FIG. 1 illustrates the network typology for an electronic mail (email) transport system. Users U 1 , U 2 , U 3 and U 4 each connect to a central email server across a network. The email server receives and stores email messages for each user. Thus, a message transported from user U 1 to a User U 3 is transmitted from User U 1 , travels across a network to an email server with whom user U 3 has an email account. At the creation of the message, ownership of the message is directed to the recipient. Once the transport begins, the originator no longer has control over the message; the recipient, user U 3 , bears ownership of the record. User U 3 must periodically check the server for messages. Depending upon the email server configuration, messages are either stored indefinitely on the server or are downloaded to user U 3 upon request. In either case, the receiving user, i.e. U 3 gains full control over the message. User U 3 may forward, delete or store the message and any attachments tied thereto. This system allows for information to be passed between users and/or institutions, however institutions do not transmit personal user information to the user.
[0014] FIG. 2 a illustrates an exemplary network topology for a user U 1 with network ties to accounting software Q 1 and to financial institutions B 1 and B 2 . Note that accounting software Q 1 also ties into financial institutions B 1 and B 2 . Thus, user U 1 has access to read and download information retained by, and bearing ownership, of financial institutions B 1 and B 2 through a user interface for each bank or though accounting software Q 1 . Financial institutions B 1 and B 2 have ties to a credit reporting agency C 1 where information regarding user U 1 is systematically updated. Financial institutions generally do not share users information. The problem with this financial system is that the financial institution bears ownership of the information and user must periodically view or download the information from the financial institutions within a limited period of time before user accessibility is removed. Accounting software Q 1 provides an ability for user U 1 to download and locally store the information, however, user U 1 must initiate the transfer; information is not transferred automatically or systematically. Additionally, the information is not readily transferable and user U 1 is solely responsible to maintaining the downloaded information. Such a system also does not address the other information needs of the user.
[0015] FIG. 2 b shows that user U 1 is disconnected from his medical records retained by, and bearing ownership of, doctors D 1 and D 2 . Ownership of medical records resides with the doctor. Doctors D 1 and D 2 have office automation software (OAS) which provides network ties to pharmacies P 1 and insurance companies 11 to address the needs of the doctors. Note too, that there is a disconnect between doctors D 1 and D 2 ; restricting the flow of medical information between doctors. Doctor D 2 must request a record from doctor D 1 which is commonly electronically mailed or sent via electronic facsimile (fax).
[0016] Thus the goal of the invention contained herein is to provide a user accessible information system wherein a user's records are readily accessible, portable and owned by the individual.
SUMMARY OF THE INVENTION
[0017] The invention contained herein addresses the aforementioned issues by providing methods for an accessible information system centred on the individual. According to the invention, records pertaining to an individual, (i.e. a user of the system) are centralized such that the user has control over the integration and dissemination of their personal and private information. The invention provides for a system wherein records pertaining to an individual are systematically transported electronically by many different institutions to a centralized record storage provider determined by the user wherein the individual user can access and control the information as needed.
[0018] FIG. 3 illustrates a network typology according to aspects of the invention using like numerology as FIGS. 1 and 2 . Users U 1 -U 4 each have accounts on, and network access to, a record server wherein their personal records are stored. Institutions including, but not limited to, financial (B 1 , B 2 , C 1 ), medical (D 1 , D 2 , P 1 , hospitals H 1 ), insurance companies (I 1 ), travel providers (T 1 ), dentists, laboratories and government agencies each transmit records to the record server systematically, in response to transactions, such that user U 1 has access to records regarding his personal affairs subsequent to the transaction.
[0019] This system has numerous advantages. With readily accessible records stored in a centrally located database, user U 1 may control the dissemination of personal information between service providers. The systematic accumulation of medical records provides for better overall health tracking and faster and more accurate diagnosis when illness or emergency occurs.
DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 illustrates a prior art network topology for transferring electronic mail (email) between users across an information network.
[0021] FIG. 2 a illustrates prior art the information links between a user, accounting software, banks and credit reporting agencies.
[0022] FIG. 2 b illustrates the prior art information links between doctors, pharmacies and insurance companies.
[0023] FIG. 3 illustrates an exemplary network topology according to the invention wherein: information records according to users are received from a plurality of institutions and controlled by the users.
[0024] FIG. 4 illustrates an exemplary flowchart of the invention detailing the user's control of their personal information.
[0025] FIG. 5 illustrates an exemplary information storage and retrieval system according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0026] FIG. 4 provides an exemplary embodiment of the invention. In a first step 405 , a user, or their guardian, creates an account and provides or receives an account identifier. The account identifier may be provided as an account number by a record storage service provider. For privacy and security purposes the account identifier may be provided on an electronic card bearing encryption methods.
[0027] In a second step 410 , the user provides their account identifier to a health practitioner, financial institution, retailer, etc. In a third, and optional step 415 , the user may permit access to specific portions of their records such that the service provider may access pertinent records prior to performing a service. For example, a second doctor may review tests and a diagnosis provided by a first doctor. Similarly, information required for a loan application may be drawn from the user's database.
[0028] In a forth step 420 , the service provider provides a service, performs a test, provides a diagnosis, accepts a deposit, closes a sale, etc.
[0029] In a fifth step 425 , the service provider utilizes the user's account identifier to insert a record into the database to document the services provided within the transaction processed. The record may include the results of an examination, blood test results, images, diagnosis, treatments, payments, products purchased, warranty information, etc.
[0030] In a sixth step 430 , the user may access their records through their record storage account. At the user's discretion, they may provide their account identifier to another service provider, thus 465 repeating the process from second step 410 .
[0031] FIG. 5 provides a block diagram of an embodiment of the invention implementing the method of FIG. 4 . More specifically, a database provider 520 maintains a database 510 , a file library 515 and provides network access 505 to users and institutions via a network interface. Thus, from a computer, a user may create an account in the record storage database for themselves or for a person whom they are an advisor or legal guardian for. Once an account has been established, the user receives an account identifier such as an account number and/or an identification card. At the time of opening a new account with an institution including private practitioners, the user provides their account identifier, so that the service provider can transport current and future transactions systematically to the user's record storage database.
[0032] Service providers and their institutions 525 normally utilize office automation software (OAS) to record a user's personal information as well as transaction records. As offices become “paperless”, meaning that all information is recorded via computer at the time of service, the information is readily available for transmission to a user oriented database. Thus, office automation software may implement aspects of the invention wherein resultant information, pursuant to a transaction, is assembled into a record and transported to a destination specified by the user. Office automation software, according to the invention, can access the user's account and insert records into the database through remote procedure calls (RPC), file transfer protocol (FTP) or other network protocol. Once a record is inserted into the database, the user can access the data, use and/or share the information. Likewise, according to the user, office automation software may transport records from the user's record storage provider as allowed by the user.
[0033] With accessible records on a network, various software applications, including mobile communication applications, may access the user's records to provide useful information services. For example, the user may receive test results on their mobile communications device or the user may show a service provider images or the visual output from a mobile application.
[0034] It is recognized that records, and their transport, must be secure and privacy maintained. To facilitate secure record transport, commonly available encryption methods may be employed. For example, the user may have a master encryption key for managing their account. The user's account identifier may comprise a second encryption key that, when given to a service provider, enables a service provider to insert records into the user's database or access records from the database.
[0035] Once user information has been entered into the user's database and transport channels established between service providers and record storage providers, the user may share information. For example, the user may grant access rights to specific information or request a transfer of information to additional parties.
[0036] The database provider may provide many services to assist the user with managing their personal information. For example, as records accumulate over time, a medically oriented application can provide the user and their current doctor with emerging trends in the health of a user. For example, changes in blood chemistry or blood pressure can be analysed; charted and presented that indicates changes in the user's health over a period of years. The database provider may also supply nutritional information for those people seeking to manage day to day personal health issues such as body weight, blood pressure and cholesterol level. If a health provider or dietician provides a strict diet, the database provider can offer meal plans and suggestions, and provide a means for the user to record consumption and calculate nutritional information to be fed back to the user's doctor or dietician.
[0037] The database provider may also provide patients with a variety of information about doctors. For example, when a patient is diagnosed with a condition, the database provider can offer links to specialists the field, their credentials, success rates and popularity with their patients.
[0038] It should be understood that the foregoing description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims.
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According to the invention, records pertaining to an individual are centralized such that the user has control over the integration and dissemination of their personal and private information. Records pertaining to an individual are systematically transported electronically by many different institutions to a centralized record storage provider wherein the individual user has ownership of and control of their confidential personal information. The systematic accumulation of medical records provides for better overall health tracking and faster and more accurate diagnosis when illness or emergency occurs.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an antenna for a plurality of radio services in the form of a dipole or monopole.
2. The Prior Art
Antennas of this type are known from German Patent DE 193 10 226 A1. The antenna described in this patent has a capacitive surface and an antenna conductor disposed substantially perpendicular relative to this surface. Together with the conductive base surface, and the decoupling of the signals as specified in this patent via the coupling conductor 15 , an antenna in the form of a monopole is used. Its direction of polarization extends substantially perpendicular to the top capacity. By arranging slots in the top capacity, the latter becomes electrically divided, depending on the frequency, so that for a monopole operation with polarization oriented perpendicular to the top capacity, a plurality of radio services are obtained on the antenna. Antennas of this type thus have the limitation that their polarization is oriented perpendicular to the top capacity. Thus it is not possible in the present state of the art for one singular antenna to communicate with several vertically polarized mobile terrestrial telephone radio services. Thus, it is not possible even if this one antenna uses either single or multifrequency communication with satellite radio services, whether linear or circularly polarized.
SUMMARY OF THE INVENTION
Therefore, it is an object of the invention to provide an antenna that provides both radio reception with a polarization perpendicular to the top capacity, and at least one additional radio service with parallel polarization relative to the top capacity. Thus this type antenna provides a combined function for radio services with planes of polarization disposed vertically, one on top of the other.
With the antenna according to the invention, it is possible to gain the advantage of covering, with one component, a great variety of terrestrial, and satellite radio services with very low cost. Particularly for mobile radio services, it is possible to design compact motor vehicle antennas which, cover the mobile telephone services GSM in the D-network (about 0.9 GHZ), and the E-network (about 1.8 GHZ) with vertical polarization, and at the same time, the satellite radio service for location determination (GPS radio service at about 1.5 Ghz). In this case, the waves arrive predominantly horizontally, and with circular polarization due to a plurality of a zenith close satellites. As opposed to the vertically polarized radio service with a gap in the directional diagram, or a pattern in the zenith, GPS navigation service requires a circularly polarized antenna and has a maximum reception at its zenith. This requirement can be advantageously satisfied at low expenditure with an antenna as defined by the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and features of the present invention become apparent from the following detailed description considered in connection with the accompanying drawings which disclose the embodiments of the present invention. It should be understood, however, that the drawings are designed for the purpose of illustration only, not as a definition of the limits of the invention.
In the drawings, wherein similar reference characters denote similar elements throughout the several views:
FIG. 1 a shows an antenna in the form of a monopole as defined by the invention, with a flat antenna conductor connected to the base surface having a roof capacity and a closed lambda/2 slot contained therein.
FIG. 1 b shows the antenna of FIG. 1 a , but with a tubular antenna conductor with a non symmetrical line in the field-free interior of the latter, and with a frequency separating filter present on the base surface.
FIG. 2 shows the antenna of FIG. 1 a , but with conductor boards coated on both sides and with two open lambda/4-elongated slots of different lengths for receiving two additional radio services at different frequencies.
FIG. 3 a shows the antenna of FIG. 2, but with two equally elongated slots arranged at an angle of about 90 degrees relative to each other.
FIG. 3 b is an electrical block diagram for an antenna as in FIG. 3 a.
FIG. 4 shows the antenna according to FIG. 2, but for two first radio services (e.g., D-network, E-network) with vertical polarization relative to the top capacity, with two additional slots for forming different resonance frequencies; and
FIG. 5 shows the vertical directional diagram of an antenna of FIG. 4 in the GPS frequency band with circular polarization.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Turning now in detail to the drawings, FIG. 1 a shows an antenna in the form of a monopole with a flatly designed antenna conductor 4 , which is conductively connected to both the top capacity 1 and the base surface. A resonance is formed in the frequency range of a first radio service by the inductive effect of antenna conductor 4 and the capacitive effect of the top capacity. It is possible in this way to form a resonant monopole antenna with a low structural height with vertical polarization relative to the top capacity. Coupling to the resonant monopole, takes place via coupling conductor 15 for forming the first antenna connection point 14 . In order to obtain the required antenna function with parallel polarization relative to the roof capacity for a further radio service using a monopole, a closed lambda/2 slot 3 with resonance in the frequency range of this further radio service is provided in roof capacity 1 . A slot with about lambda/4 length that is open at one end can be formed as well. Suitably selected connection points 9 a and 9 b , which oppose each other on the edges of the slot, with a spacing 25 from the closed end of the slot, permit adjustment of the desired antenna impedance. Moreover, the width of the slot permits adjustment of the desired bandwidth. A non symmetrical line 10 , is connected to connection points 9 a , 9 b , and is electrically neutral with respect to the monopole function of the antenna. Line 10 is installed parallel with the conductive surfaces of roof capacity 1 and antenna conductor 4 , and connected between connection points 9 a and 9 b . A further antenna connection point 13 is located on the conductive base surface 2 .
FIG. 1 b . shows an antenna in the form of a monopole as in FIG. 1 a but with a tubular antenna conductor 4 . The non symmetrical line 10 is installed in the field-free interior of this conductor. The first antenna connection point 14 is formed at the lower end of antenna conductor 4 with the conductive base surface 2 . To extend the antenna connection for additional radio service, a frequency separation filter 16 is formed at or in the bare point. In the interior of the filter, the extension of a non symmetrical line 10 is provided in the form of a choke coil that has a high impedance in the first frequency range. Antenna connection point 13 is designed not to impair the monopole function of the antenna.
In FIG. 2, roof capacity 1 and the vertically oriented, flatly designed antenna conductor 4 are designed as conductor boards which are coated on both sides, providing an advantageous embodiment to the invention. The conductive surfaces are formed by the conductive material present on the one side of the conductor boards, and the surfaces are electrically connected on the abutting edge. The non symmetrical line is designed in the form of a strip line 10 , whereby the strip conductor is printed on the opposite side of the conductive surface 1 , and the surface forms the ground conductor of line 10 . The connection between the strip conductor of strip line 10 and connection point 9 a can be established simply way through-contacting. Connection point 9 b is defined by the run of the strip conductor, which extends perpendicular to the direction of the slot—as the point on the edge of the slot opposing point 9 a . To illustrate the idea of the invention, FIG. 2 shows two slots 3 with different lengths (approximately λ/4) and different directions of polarization within the two common polarization planes parallel with the roof capacity, with non symmetrical lines 10 , which are separated from each other, and additional antenna connection points 13 . It is possible in this way to cover additional radio services with different frequencies for the same polarization plane.
As a further advantageous embodiment of the invention, FIG. 3 a shows an antenna wherein the conductive base surface is oriented horizontally, and the monopole antenna is tuned for the frequency band of a terrestrial radio telephone service with vertical polarization as the first radio service, and further tuned to a satellite radio service with waves substantially incident with horizontal polarization as the second radio service.
Such an antenna is particularly suitable, for example for combining the terrestrial GSM telephone service with the GPS satellite radio service for application as a motor vehicle antenna with a horizontal conductive surface 2 . In this case, the roof capacity and the antenna conductor 4 , which is vertically oriented relative to said roof capacity, are dimensioned so that resonance exists in the GSM frequency range. Slot 3 is designed with respect to its length and width so that its resonance is suitable for receiving the GPS signals. In order to satisfy both the requirement of maximal radiation in the zenith, and at the same time, circular polarization, two slots 3 are provided, each with two connection points, whereby points 9 a and 9 b each have a non symmetrical line 10 connected thereto for the further GPS radio service with circular polarization. The slots in the conductive board of the roof capacity are oriented for this purpose at an angle of almost 90° relative to each other so that the reception of the circularly polarized waves is optimized with a preset direction of rotation. Both slots are designed, for example as lambda/4 resonant slot lines with open ends on the edge of the top capacity. The spacing 25 of connection points 9 a , 9 b is preferably selected with respect to the wave resistance of the line connected thereto. At their other ends, the two lines are connected to the two inputs of a 90° hybrid circuit, in which one of the two signals received is changed in the phase by 90° and, following the correctly polarized combination of the signals on the output of the hybrid circuit, the correct circular direction of polarization is present in antenna connection point 13 .
An advantage of the invention is its simple design using printed conductor boards for producing the conductive surfaces and the lines. This technology permits, in the manufacturing process very good reproducibility of the finely coordinated structures. Roof capacity 1 and the vertically oriented, flatly designed antenna conductor 4 are designed in this connection as pc boards which are conductively coated on both sides, whereby the conductive material present on one side of the pc boards forms in each case, the conductive surface. The non symmetrical line 10 is designed in this case as a strip line, whereby the strip conductor is printed on the opposite side of the conductive surface, and the conductive surface forms the ground conductor of the line.
Relatively good decoupling between antenna connection points 13 and 14 is advantageous with the invention as well. Due to the extremely great differences of the signal strength between the emitted GSM-signals and the GPS-signals to be received, it is advantageous to connect a bandpass filter 27 for this frequency range downstream of antenna connection point 13 as shown in FIG. 3 b in order to protect the sensitive GPS receiver against nonlinear effects caused by high signal levels, In order to achieve a good signal-to-noise ratio in the GPS range, it is advantageous to add a low-noise preamplifier 24 without loss-afflicted feed lines. In order to avoid the sideband noise of GSM radio transmitters 28 in the GPS frequency range, it is recommended that a band stop filter 26 be connected upstream of antenna connection point 14 .
To provide for an antenna function for an additional first radio service with a higher frequency and with a polarization with vertical orientation relative to the conductive base surface, it is possible to incorporate slots 22 in top capacity 1 in the manner known per se. FIG. 4 shows such an antenna for the two terrestrial mobile telephone services (D- and E-networks). With the help of the notches 18 , it is possible to determine the slot lengths and the top capacity for forming the different resonance frequencies largely separated from each other.
With the antenna shown in FIG. 4 it is possible to receive in addition to the radio services of the D- and E-networks, the satellite navigation service GPS via a further connection point 13 .
As opposed to the vertically polarized first radio service with a gap of the directional diagram in the zenith, the GPS navigation service requires a circularly polarized antenna with a maximum of the reception in the zenith. Two additional slots, which are arranged at an angle of 90 degrees relative to each other, are thus incorporated in the conductive surface of top capacity 1 , and operated as lambda/4 slot antennas. The input impedance of the slots effective for the edge current of the D-network is sufficiently low impedance because the slots have a highly pronounced resonance at 1.575 GHZ, so that the radio antenna is not influenced in the D-network.
The decoupling points of the two GPS slot antennas are placed together as closely as possible and selected in such a way that their impedance amounts to 50 ohms. The HF-signals of the GPS antennas are conducted with coaxial lines via antenna conductor 4 to a 90-degree hybrid, using the conductive surface of roof capacity 1 as the ground conductor.
If doubly coated board material (e.g., FR4) of 1 mm thickness is employed for the conductive surface of roof capacity 1 for the antenna according to FIG. 4, all slots can be etched on the top side from the applied coating of copper. The two required HF-lines for GPS are realized as microstrip lines, whereby the underside of the board carries or supports the strip conductors. The GPS signals are passed on via antenna conductor 4 via microstrip lines as well and connected to the 90-hybrid on the base plate, the hybrid being designed in strip line technology as well. This results in an antenna which can be structured in a simple manner, and which is easily reproducible.
FIG. 5 is a plot of a measured vertical section of the directional diagram of the antenna according to FIG. 4 in the upper hemisphere with circular polarization. Due to the fact that the GPS slot antennas according to FIG. 4 are present in an environment which is non symmetrical, diagram catchments or losses are experienced in the 60° to 90° elevation range with respect to other azimuth angles. IEEE Standard Gain antenna with geometric dimensions adapted to the GPS frequency band was employed as reference antenna. The performance of a ceramic patch antenna is achieved in all other respects.
While several embodiments of the present invention have been shown and described, it is to be understood that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention as defined in the appended claims.
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The invention relates to a mobile antenna for a plurality of radio services in the form of a dipole or monopole, with an antenna conductor and with at least one flatly designed roof capacity disposed substantially vertical relative to the antenna conductor for a first radio service with polarization disposed vertically relative to the roof capacity. The roof capacity is designed in the form of a conductive board or a thin conductive layer. In order to create an antenna function for at least one additional radio service with polarization oriented parallel with the roof capacitance, at least one slot is incorporated in the conductive board or layer with the slot length selected to form a suitable impedance bandwidth. In order to decouple signals of an additional radio service, first and second connection points are formed on the edges of the slot, wherein the connecting points oppose each other.
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[0001] The application claims the filing-date priority of Provisional Application No. 61/528,148 filed Aug. 27, 2011; and application Ser. No. 12/636,757, filed Dec. 13, 2009 (which claims priority to Provisional Application No. 61/138,014, filed Dec. 16, 2008); and application Ser. No. 12/903,149, filed Oct. 12, 2010 (which claims priority to Provisional Application No. 61/251,255, filed Oct. 13, 2009). This application is a continuation application of PCT Application PCT/US12/52549, filed Aug. 27, 2012. The disclosure of each of these applications is incorporated herein in its entirety.
BACKGROUND
[0002] 1. Field of the Disclosure
[0003] The disclosure relates to method and apparatus for microcontact printing of microelectromechanical systems (“MEMS”). More specifically, the disclosure relates to a novel method and apparatus for release-assisted microcontact printing of MEMS.
[0004] 2. Description of Related Art
[0005] MEMS applied over large areas would enable applications in such diverse areas as sensor skins for humans and vehicles, phased array detectors and adaptive-texture surfaces. MEMS can be incorporated into large area electronics. Conventional photolithography-based methods for fabricating MEMS have provided methods and tools for producing small features with extreme precision in processes that can be integrated with measurement and control circuits. However, the conventional methods are limited to working within the existing silicon semiconductor-based framework. Several challenges, including expense, limited size and form-factor, and a restricted materials set, prevent the future realization of new MEMS for applications beyond single chip or single sensor circuits. Standard processing techniques are particularly restrictive when considering expanding into large area fabrication. Conventional photolithography methods are also incompatible with printing flexible substrate MEMS and micro-sized sensor arrays.
[0006] For example, in creating free-standing bridges, cantilevers or membranes from limited material, the conventional methods require surface or bulk micromachining, a series of photolithographic masking steps, thin film depositions, and wet chemical or dry etch releases. Such steps require investing in and creating highly specialized mask sets which render conventional photolithography expensive and time and labor intensive. While the initial investment can be recovered by producing large batches of identical MEMS devices, the conventional methods are cost prohibitive for small batches or for rapid prototype production.
[0007] Conventional MEMS have been based on silicon and silicon nitride which are deposited and patterned using known facile processes. Incorporating mechanical elements made of metal on this scale is difficult because of the residual stresses and patterning challenges of adding metal to the surface. This is because metals are resistant to aggressive plasma etching. As a result, conventional MEMS processing apply liftoff or wet chemical etching. The surface tension associated with drying solvent during these patterning steps or a later immersion can lead to stiction (or sticking) of the released structure. Stiction dramatically reduces the production yield.
[0008] Another consideration in some large area applications is flexibility. Although photolithography is suitable for defining high fidelity patterns on planar and rigid substrates, it is difficult to achieve uniform registration and exposure over large areas. Display technologies have been among the first applications to create a market for large area microelectronics. To meet the challenges of new markets for large area electronics, alternative means to patterning have been proposed which include: shadow masking, inkjet printing, and microcontact printing. These techniques are often the only options available for organic semiconductors and other nanostructured optoelectronic materials, some of which have particularly narrow threshold for temperature, pressure and solvent. Conventional methods are not suitable for MEMS using organic semiconductors, nanostructured optoelectronic materials which may be fabricated on a flexible substrate.
[0009] An alternative approach is to fabricate electronic structures directly on flexible sheets but polymeric substrates offering this flexibility are typically limited to low-temperature processing as they degrade under high temperature processing. Accordingly, high temperature processing such as thermal growth of oxides and the deposition of polysilicon on a flexible substrate cannot be supported by conventional processes. Another approach is to fabricate structures on silicon wafers, bond them to a flexible sheet, and then release the structures from the silicon by fracturing small supports or by etching a sacrificial layer. However, this approach tends to locate the structures on the surface having the highest strain during bending.
[0010] Therefore, there is a need for an improved process that addresses these and other shortcomings of the art.
SUMMARY
[0011] The disclosure provides methods and apparatus for release-assisted microcontact printing of MEMS. The principles disclosed herein enable patterning diaphragms (interchangeably, membranes) on a substrate having articulations of desired shapes and sizes. Such diaphragms deflect under applied pressure or force (e.g., electrostatic, electromagnetic, acoustic, pneumatic, mechanical, etc.) generating a responsive signal. Alternatively, the diaphragm can be made to deflect in response to an external bias. The disclosed principles enable transferring thin diaphragms without rupturing the diaphragm. The diaphragm can define a single material or a composite of different materials or layers.
[0012] In one embodiment, the disclosure provides a method for forming a MEMS device by contacting a support structure having a diaphragm formed thereon with the MEMS structure. The contact results in transfer of the diaphragm from the support structure onto the MEMS structure. The support structure includes a release layer separating a substrate from the diaphragm. A diaphragm of desired shape and thickness is thus formed over the release layer. The release layer is weakened prior to transferring the diaphragm in order to ease the contact-transfer process. The diaphragm can have varying surface thickness and area. In an exemplary embodiment, the diaphragm had a surface area of less than 0.2 mm 2 . In another embodiment, the diaphragm surface area was about 0.2-16 mm 2 . In still another embodiment the diaphragm surface area was larger than 16 mm 2 . In another exemplary embodiment, the membrane area is as small as 100 nm 2 or less.
[0013] In another embodiment, the disclosure relates to a method for forming a MEMS structure. The method includes the steps of: providing a MEMS structure having an articulation thereon; interposing a release layer between a first surface of an electrode and a substrate; contacting a second surface of the electrode with the MEMS structure to form an interim structure; activating the release layer in the interim structure to separate the substrate from the first surface of the electrode; removing the substrate from the interim structure to form an electrode at least partially covering the articulation. The step of contacting a second surface of the electrode with the MEMS structure may additionally include adhering the second surface to the MEMS structure to at least partially cover the articulation. In another embodiment, the interim structure is exposed to a vapor to activate the release layer. The vapor may contain one or more solvents. Alternatively, the interim structure may be exposed to heat and/or radiation to activate the release layer. Activating the release layer is intended to reduce adhesion of the release layer, thereby allowing separation and transfer of the electrode from one surface to another. The articulation may be a cavity, an aperture, a dimple, a post, a pillar or a plurality of ridges. A plurality of cavities, apertures or dimples can also be interconnected to each other by generating channels between them or by connecting adjacent cavities, apertures or dimples to each other. The MEMS structure can be a patterned metal feature, an insulator, a semiconductor, a conductive material, two conductive materials separated by an insulator, an organic material, a viscoelastomer, a polymer or a combination thereof.
[0014] In another embodiment the disclosure relates to a pressure sensor. The pressure sensor includes an array of cavities formed in a substrate, each cavity having a hollow interior separating a top portion and a bottom portion; a diaphragm layer formed over the array; a first electrode communicating with the plurality of diaphragm layers defining a plurality of complementary electrodes; a meter in communication with the plurality of complementary electrodes for detecting a capacitance change between at least one first electrode and its respective diaphragm when an external signal impacts the diaphragm. The sensor may also include a controller in communication with the meter, the controller can have a processor circuit in communication with a memory circuit, the controller receiving a signal from the meter and identifying a pressure change corresponding to the received signal. In another embodiment, the controller communicates with the meter, the controller having a processor circuit in communication with a memory circuit and the controller receiving a signal from the meter and identifying a change in capacitance corresponding to the received signal. In still another implementation, at least one of the complementary electrode pairs determines a change in potential between the first electrode and the diaphragm when the diaphragm is deflected. In yet another embodiment, the array defines a plurality of pixels in which the diaphragm can independently be addressed.
[0015] In another embodiment, the disclosure relates to a method for forming a MEMS structure. The method comprises the steps of: providing a MEMS structure having an array of articulations in which at least two adjacent articulations are separated by a pitch distance; providing a support structure, the support structure having a first and a second release layers interposed between a substrate and a diaphragm; exposing the support structure to one of a first solvent or a first energy source configured to dilute or dissociate the first release layer; contacting a second surface of the electrode with the MEMS structure to form an interim structure; exposing the interim structure to one of a second solvent or a second energy source configured to dilute or dissociate the second release layer; and removing the substrate from the interim structure to form an electrode at least partially covering the two adjacent articulations. The step of exposing the release structure to a solvent, an energy source or a combination thereof can be identified as the activating step. The first release layer and the second release layer can be identical or different material. The first release layer can be an organic release layer decomposable by solvent and the second release layer can be photo- or heat-sensitive and decomposable by radiation or heat energy. The interim structure can be exposed to solvent or energy in a chamber or a housing adapted to receive the structure.
[0000] A transducer according to an embodiment of the disclosure includes a plurality of cavities formed on a substrate, the cavities organized in rows and columns wherein at least two adjacent cavities are separated by a pitch distance and wherein the plurality of cavities define a first group and a second group; a diaphragm layered over the first and the second group of cavities; a first electrode communicating with the first plurality of cavities; a second electrode communicating with the second plurality of cavities; a controller having a processor circuit in communication with a memory circuit, the controller independently communicating with each of the first group and the second group of cavities. The controller may activate the first group of cavities independently of the second group of cavities. The activation of the cavities can be done by applying a bias voltage/current. Once biased, the diaphragm expands or contracts responsive to the supplied bias. Conversely, the diaphragm may expand or contract responsive to an external bias (e.g., pressure, acoustic or electrostatic force). In this manner, the deflection of the diaphragm can be registered and measured to determine the intensity of the external bias. In an exemplary implementation, a plurality of addressable cavities are identified in which the controller can manipulate the diaphragm independently.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] These and other embodiments of the disclosure will be discussed with reference to the following exemplary and non-limiting illustrations, in which like elements are numbered similarly, and where:
[0017] FIG. 1A is a schematic representation of a conventional MEMS device;
[0018] FIG. 1B shows an application of the MEMS device of FIG. 1A as an actuator;
[0019] FIG. 1C shows an application of the MEMS device of FIG. 1A as a sensor;
[0020] FIGS. 2A-2D are schematic representations of a method for constructing electrodes;
[0021] FIG. 3 pictorially illustrates an exemplary process for release-assisted contact-transfer fabrication of MEMS;
[0022] FIG. 4A is a contact profilometry scan of the pick-up stamp according to one embodiment of the disclosure;
[0023] FIG. 4B is an optical microscopy image of a gold diaphragm formed according to one embodiment of the disclosure;
[0024] FIG. 5 shows an exemplary process for PDMS lift-off transfer;
[0025] FIG. 6 schematically illustrates a MEMS structure prepared according to the process of FIG. 5 ;
[0026] FIG. 7 is an optical micrograph of the MEMS devices whose structure is shown in of FIG. 6 ;
[0027] FIG. 8 shows photographs of gold diaphragms formed on a substrate using the release-assisted transfer technique;
[0028] FIG. 9 shows a MEMS device formed according to an embodiment of the disclosure;
[0029] FIG. 10 shows a MEMS device in which the diaphragm is collapsed over a region of the device;
[0030] FIG. 11 shows an optical interferometry image of the gold diaphragm of Example 1 under 15 V (DC) actuation;
[0031] FIG. 12 shows the optical interferometry image of the gold diaphragm under AC actuation at different phase angles;
[0032] FIG. 13 is an optical interferometry image of the deflected gold diaphragm due to external bias;
[0033] FIGS. 14A-14C show large area diaphragms formed according to the disclosed embodiments;
[0034] FIG. 15 shows the deflection profile of a gold diaphragm at 15V bias obtained by optical interferometry;
[0035] FIGS. 16A-16C represent deflection profiles of diaphragms under electrostatic pressure; and
[0036] FIG. 17 shows an exemplary microprocessor-controlled array according to one embodiment of the disclosure.
DETAILED DESCRIPTION
[0037] FIG. 1A is a schematic representation of a conventional MEMS device. MEMS 100 includes substrate 110 having supports 112 and 114 . Supports 112 and 114 can be viewed as a plurality of ridges separated by gap 115 . Supports 112 and 114 uphold diaphragm 116 . Gap 115 is defined by the separation distance between ridges 112 and 114 and by the height (d). Conventionally, diaphragm 116 is defined by a metal layer and MEMS structure 100 is formed through photolithography. As stated, the conventional processes lacked ability to produce MEMS devices over large areas and on flexible substrates.
[0038] FIG. 1B shows an application of the MEMS device of FIG. 1A used as an actuator. In FIG. 1B , structure 100 is connected to voltage source 120 through substrate 115 (fixed electrode) and diaphragm 116 (deflecting electrode). The bias provided by voltage source 120 creates an electrostatic force between fixed electrode 115 and diaphragm 116 , causing the latter to deflect towards fixed electrode 115 . The relationship between the electrostatic force and the deflection is described in Equation 1 as follows:
[0000] F el ∝V 2 /d 2 (1)
[0039] In Equation 1, F el denotes the electrostatic force, V is the bias voltage and d is the separation distance between substrate 115 and metal layer 116 .
[0040] FIG. 1C shows an application of the MEMS device of FIG. 1A for use as a sensor. In FIG. 1C , external force F ext is applied to MEMS structure 100 causing deflection in diaphragm 116 . The external force is measurable as it creates a change in capacitance (C) of device 100 . The capacitance can be determined by Equation 2 as follows:
[0000] C∝ 1 /d (2)
[0041] Any material which can be formed into a film can be used as a diaphragm. Such materials include viscoelastic polymers and conductive films. A conductive material such as a metal, a conducting metal oxide, graphene sheet, molybdenum disulfide sheets, polymer thin film, metal oxide/nitride/sulfide membrane or a doped polymer can be used as diaphragm. Additionally, boron nitride and similar two-dimensional (2D) conducting, insulating, semiconducting, or superconducting sheets can also be used as a diaphragm. In another embodiment, an electrically insulating membrane is coated with a conductive layer to form a diaphragm. The diaphragm can comprise a patterned metal feature, an insulator, a semiconductor material, a conductive material, two conductive materials separated by an insulator, an organic material or a combination thereof.
[0042] FIGS. 2A-2C are schematic representations of a method for constructing electrodes according to one embodiment of the disclosure. The method can be defined as lift-off patterning. The exemplary method starts in FIG. 2A by providing substrate 210 (fixed electrode) having thereon release layer 212 and metal film 214 . Substrate 210 can comprise glass, plastic, PDMS, silicon or silicon-based substrates, quartz, metals and other suitable material.
[0043] Release material 212 may include conventional release material. A preferred release layer comprises N,N′-diphenyl-N-N′-bis(3-methylphenyl)-(1,1′-biphenyl)-4,4′-diamine (“TPD”), Alq3 or other organic material having a desired thickness. The thickness of the release layer is a function of the release material. Exemplary implementation of release layer having thickness of 90-250 nm have proved successful. The release layer can be as thin as a monolayer. The metal layer preferably comprises a material capable of acting as an electrode (deflecting electrode) or a diaphragm. In one embodiment, metal layer 214 defines a gold layer with a thickness in the range of 70-250 nm. The metal layer can be deposited, for example, through shadow masking over the release layer.
[0044] Next, as illustrated in FIG. 2B , a MEMS structure (i.e., stamp 216 ) having a support layer and a plurality of ridges is provided. The ridges in FIG. 2 are exemplary and other features or articulations including pillars, dimples, mesas and cavities may also be used. A plurality of cavities, apertures or dimples can also be interconnected to each other by generating channels between them or by connecting adjacent cavities, apertures or dimples to each other. The MEMS structure is prepared as a function of its intended use. A common MEMS structure which can be used in applications ranging from pressure sensors to array detectors includes a base layer supporting a plurality of ridges. The base layer can act as the fixed electrode. The ridges can be spaced apart such that each pair of adjacent ridges is separated by a gap. The gap size can be configured to accommodate the desired MEMS function. In non-limiting exemplary embodiments, the gap height was as small as 0.2 nm, as large as 500 μm and heights there between. The width of the gap, cavity, dimple, or articulation can be as small as a couple of nanometers or larger for desired application. In FIG. 2C , the stamp is lifted from the substrate, removing with it a layer of release material. Here, metal film 214 breaks off at the gaps such that portions adhere to stamp 216 while other portions adhere to release layer 212 . In an alternative embodiment shown in FIG. 2D , metal layer 214 remains intact after separation such that metal layer 214 forms a diaphragm over the stamp ridges as shown.
[0045] Successful patterning also depends on the film thickness. In one embodiment of the disclosure thin metal films having a thickness of less than 20 nm replicated features as small as 13 μm. Thicker metal films having thickness in excess of about 100 nm are generally highly resistant to patterning. Instead, these thick films are seen to produce continuous film transfer across discontinuous stamp surfaces (see FIG. 2D ). By engineering the transfer process according to the film thickness, the suspended membranes and bridges which are used in many MEMS devices can be created in an additive process.
[0046] FIG. 3 pictorially illustrate an exemplary process for release-assisted contact-transfer fabrication of MEMS. The process of FIG. 3 can be viewed as a three-part process. In the pick-up stamp fabrication process, a silicon dioxide (SiO 2 ) layer was deposited on a silicon (Si) substrate by plasma-enhanced chemical vapor deposition. The silicon dioxide layer had a thickness of about 400 nm. Next, a photoresist (PR) layer was spun over the SiO 2 layer. The PR layer was then patterned and developed. Thereafter, the PR layer was dry etched using CF 4 to form cavities. The photoresist was removed in oxygen plasma and the completed stamp was treated with 3-mercaptopropyltrimethoxysilane (“MPTMS”) at about 80° C. for about 24 hours.
[0047] In the transfer pad fabrication process, PDMS transfer pad was treated with oxygen plasma for about 35 seconds to form cured PDMS. Next, an organic release layer of TPD was thermally evaporated over the PDMS mesas. The metal diaphragm (gold) was thermally evaporated on top of the organic release layer.
[0048] Finally, acetone was applied to the transfer pad in order to activate the release layer prior to the transfer process. The acetone treatment is intended to substantially weaken, degrade, dissolve, dilute or dissociate (activate) the release layer. The degradation may be a chemical degradation in which the release layer is treated with one or more solvents in order to weaken the intermolecular forces/bonds of the release layer. By degrading the release layer, delamination of the diaphragm from the underlying layer is significantly expedited. Suitable solvents for weakening the release layer may include acetone, methyl ethyl Keaton (MEK), water or other conventional solvents. The weakening of the release layer may be done before or after the step of contacting the MEMS structure with the diaphragm-supporting structure. As will be discussed further below, the weakening of the release layer may also be done by exerting energy, alone or in combination with a solvent.
[0049] The third and final step of the process is the transfer process whereby the pick-up stamp is brought into conformal contact with the gold film on the transfer pad. The pick-up stamp is then lifted away from the diaphragm, resulting in the diaphragm bridging the cavities of the stamp. In the exemplary embodiment of FIG. 3 , the Si layer acts as the fixed electrode and the gold diaphragm acts as the deflecting electrode. The two electrodes are separated by the cavities formed in the SiO 2 layer.
[0050] FIG. 4A is a contact profilometry scan of the pick-up stamp made according to one embodiment of the disclosure. As seen in FIG. 4 , the pick-up stamp consisted of 400 nm thick SiO 2 spacer layer on a silicon substrate. The SiO 2 spacer layer was patterned with circular cavities in a hexagonal-close-packed arrangement. The cavities can be formed in silicon, polysilicon, silicon dioxide, metal, insulator, metal coated with an insulator, silicon dioxide on silicon, other silicon based substrates, quartz and other suitable material. While the exemplary embodiment of FIG. 4A shows a constant the pitch distance between the cavities, the disclosed principles are not limited thereto and include varying pitch distances on the same MEMS structure.
[0051] FIG. 4B is an optical microscopy image of a 0.8 mm 2 area gold diaphragm formed according to one embodiment of the disclosure. Specifically, FIG. 4B shows a MEMS capacitor array of about 1024 cavities covered by a single 125+/−15 nm thick gold diaphragm. The diaphragm was formed using solvent-assisted contact transfer process exemplified in FIG. 3 . The underlying SiO 2 layer was patterned with about 27 μm diameter circular cavities with 4 μm pitch spacing. It should be noted that the diaphragms disclosed herein can comprise of single material or a composite of different materials including conductive material, non-conductive material and/or a combination thereof. Non-limiting and exemplary diaphragm material include gold, silver, alloys or combinations thereof. In addition, the diaphragm may comprise a combination of a conductive and a non-conductive material.
[0052] In an embodiment of the disclosure, an insulating layer is formed between the diaphragm (top deflectable electrode) and substrate (bottom fixed electrode) to prevent shorting. For the PDMS MEMS devices, this can be a thin layer of PDMS. For the silicon dioxide or silicon-based MEMS structures, the insulating layer can be about 30 nm thick layer of silicon dioxide or silicon nitride.
[0053] FIGS. 5A-5C show an exemplary process for contact-transfer printing according to another embodiment of the disclosure. Here, a MEMS structure and a diaphragm support structure were used to illustrate contact transfer. MEMS structure 500 includes electrode 525 and PDMS 515 . PDMS 515 is defined by proximal and distal sides. The proximal side of PDMS 515 faces electrode 525 . The distal side of PDMS 515 includes a plurality of ridges that are spaced apart. Support structure 550 includes release layer 560 and metal diaphragm (deflecting electrode) 570 .
[0054] In FIG. 5B , MEMS structure 500 and transfer pad 550 are brought into conformal contact. The combination of MEMS structure 500 and transfer pad 550 define interim structure 580 . Each of the ridges formed on the distal end of PDMS 515 contacts metal diaphragm 570 . The duration of the contact can be a function of the metal layer and the pressure applied. In FIG. 5C , MEMS structure 500 is peeled off from transfer pad 550 . The peeling speed can be optionally considered to ensure substantial implementation of the process. A portion of the release layer 560 may also be removed along with the delaminated metal layer and transfers over to the MEMS structure. Conventional methods can be used to remove any excess release material transferred over to the MEMS structure 500 . Once metal diaphragm 570 is transferred, the metal layer adheres to the ridges at the distal end of PDMS 515 .
[0055] Release layer 560 can be weakened, diluted or dissociated prior to contacting transfer pad 550 with MEMS structure 500 (shown in FIG. 5A ). This can be done, for example, by treating the release layer with an etchant. The etchant can be a solvent. In an embodiment where the release layer is an optically sensitive compound, it may be weakened by exposure to radiation. The release layer may also be selected so as to weaken by heating, cooling or upon exposure to electromagnetic waves. Weakening the release layer prior to forming the final MEMS structure of FIG. 5C eases the delamination step.
[0056] The release layer may also be weakened, diluted or dissociated after forming interim structure 580 . Here, the interim structure 580 is exposed to one or more of solvent(s), vapor, heat or radiation to weaken release layer 560 . For example, interim structure 580 can be exposed to vaporized solvent, such as acetone vapor, in a reaction chamber in order to weaken the release layer prior to delaminating or separating the MEMS structure. Heat and/or radiation can also be used separate from, or in addition to, the vapor to weaken the release layer. Weakening the release layer eases delamination and allows for quicker recovery of the final MEMS structure.
[0057] The contact delamination of FIGS. 5A-5C can be implemented on diaphragm films of different thicknesses. In one embodiment, a metal layer having thicknesses between 80-140 nm was delaminated. Weakening the release layer enables contact-transfer of even thinner films. Once transferred, the diaphragm forms a suspended membrane over the articulations of the MEMS structure.
[0058] FIG. 6 shows a MEMS structure prepared according to the process illustrated in FIGS. 5A-5C . The MEMS structure of FIG. 6 includes substrate 610 which supports electrode 620 . Grating 630 is formed over the substrate and the diaphragm 640 is transferred over grating 630 . In an exemplary implementation, gold diaphragm having 140 nm thickness was transferred over grating 630 .
[0059] FIG. 7 is a top view of the MEMS structure of FIG. 6 . Specifically, FIG. 7 shows an optical microscopy image of gold electrodes transferred onto a MEMS structure. As discussed in relation to FIG. 6 , the transferred gold membrane is spread over the ridges of the MEMS support structure, making contact with a plurality of the ridges.
Example 1
[0060] A MEMS device was fabricated on patterned-silicon-dioxide-on-silicon substrate (SiO 2 on Si) using contact-transfer stamping process outlined above. The fabrication steps comprised forming a transparency mask, forming the master mold, forming pick-up stamp substrates, forming transfer pad with raised mesas and contact-transfer of the mesa diaphragm onto the MEMS structure.
[0061] Photolithography Transparency Masks—The first step in fabricating the diaphragm involves making the transparency masks that define the desired geometry. The masks can be used in ultraviolet (UV) photolithography for patterning photoresists. UV photolithography was used for making SU-8 masters that were then used as molds for patterning the PDMS transfer pad. EPON SU-8 (MicroChem Corp.®; SU-8 3010) is a commonly used epoxy-based photoresist. The portion of SU-8 resist that is exposed to light becomes insoluble to the SU-8 photoresist developer, propylene glycol monomethyl ether acetate (PGMEA), while the unexposed portion of the SU-8 resist is dissolved away by the SU-8 developer. Two different transparency masks were made.
[0062] Mask A was designed to mold raised parallelogram mesas on the PDMS transfer pad. The formed parallelogram mesas were either 0.8 mm 2 or 0.2 mm 2 in area with internal angles of 60 degrees and 120 degrees to maximize the number of hexagonal-close-packed air cavities completely covered by each parallelogram. Mask B was designed to form circular air cavities in silicon dioxide layer on top of a conducting silicon substrate (or on top of any other conducting substrate). It formed cavities of about 12.5 μm in radius, that were hexagonal-close-packed with a spacing of about 5 μm between adjacent circles.
[0063] Forming SU-8 Master Molds—To fabricate the master mold for the transfer pad, SU-8 photoresist was spun onto silicon wafer. Specifically, SU-8 photoresist was poured onto the silicon wafer and the wafer was spun at 1000 rpm such that the SU-8 covered the entire surface of the wafer. This wafer was then spun at 3000 rpm for another 30 seconds. The wafer was then soft-baked at 95° C. for 5 minutes. The wafer was cooled for 2 minutes before being placed in an Amergraph UV exposure unit with Mask A placed on top of the SU-8 photoresist layer. The mask emulsion was in contact with the SU-8 layer. Mask A was used to make the SU-8 masters for the transfer pad. The SU-8 photoresist was then exposed to UV light. After UV exposure, the wafer was baked at 95° C. for 2 minutes. The wafer was then immersed in SU-8 developer solution (PGMEA) for 4 minutes while being agitated. Thereafter, the wafer was sprayed with PGMEA for 10 seconds to rinse off residual SU-8. An isopropanol wash was used to remove the PGMEA. The wafer was dried with nitrogen and hard-baked for 3 hours at 150-170° C. to finish the SU-8 masters. Following the hard bake, the SU-8 master mold was silanized with trichloro(1H,1H,2H,2H-perfluorooctyl)silane (Sigma-Aldrich®) to ensure easy removal of the cured PDMS.
[0064] Forming Pick-up Stamp Substrates—The pick-up stamp was fabricated by cleaning a silicon wafer using the standard Piranha process. Then a layer of silicon dioxide, about 300 nm to 12 μm thick, was grown on top of the silicon substrate wafer by plasma-enhanced chemical vapor deposition (PECVD). Following that, a photoresist was spun onto the silicon dioxide surface and was soft-baked by heating it at 95° C. Then a mask aligner was used to align Mask B to the silicon dioxide surface of the silicon substrate. The photoresist was exposed and developed. The undeveloped photoresist was washed away. The silicon dioxide was then dry etched with an etchant to get cavities in the silicon dioxide layer. The remaining resist was then removed with acetone or ashed away. The surface of the resulting pick-up stamp was modified via chemical treatment with an appropriate silane or other chemicals (for example 3-mercaptopropyltrimethoxysilane) to aid in the printing/transfer of the gold membrane. The partially-doped or highly-doped silicon substrate acts as the bottom electrode of the sensor or actuator MEMS. The silicon substrate can be replaced by a glass substrate with very thin (tens of nanometers thick) metal electrode patterns on its surface. The spacer layer silicon dioxide (which was eventually patterned) can then be grown/deposited atop this glass surface patterned with metal electrodes.
[0065] Transfer Pad with Raised Mesas—The transfer pad was fabricated by pouring PDMS (Sylgard 184, Dow Corning Co.®), mixed in a 10:1 base-to-curing-agent ratio by weight and degassed under vacuum, onto a silanized SU-8 master (can be silicon/metal/silicon dioxide/other material master also) with parallelogram troughs, in a petri dish. The PDMS was then cured in an oven at 50-60° C. for about 6 hours. The curing time and temperature can have a broad range depending on the experimental conditions. The cured PDMS transfer pad was then peeled from the SU-8 master.
[0066] The resulting transfer pad had raised parallelogram mesa structures that rise above the plane of the PDMS substrate. The mesas aid with the patterning and transfer of the gold electrodes because thermal evaporation is a line-of-sight process. After the curing process, the transfer pad was exposed to oxygen plasma (100 W, Plasma Preen, Inc.®) for about 30 seconds, after which a 90 nm thick organic release layer of N,N′-diphenyl-N,N′-bis(3-methylphenyl)-(1,1′-biphenyl)-4,4′-diamine (TPD, Luminescence Technology Co.®) and a 140 nm or 150 nm thick layer of gold were deposited in sequence via thermal evaporation onto the transfer pad to define the gold electrodes on the parallelogram mesas of the transfer pad. The gold electrode thickness of 80-140 nm can also be formed using the principles disclosed here. The thin gold films, vacuum-evaporated on top of the parallelogram mesas, broke along the sharp edges of the mesas defining a gold film in the shape of the parallelogram. Therefore, the raised areas on the transfer pad define, with sub-micron resolution, the shape of the gold electrodes that were lifted-off onto the pick-up stamps as the raised areas come into contact with the pick-up stamp.
[0067] Contact Lift-Off Transfer—Following the thermal evaporation, about 100 μL or less of acetone solvent was applied onto the gold-film-covered surface of the transfer pad. The amount of acetone depends on the area of the substrate that is being transferred. Before the solvent evaporated, the pick-up stamp with circular cavities was brought into contact with the parallelogram gold films on the mesas of the transfer pad. The pick-up stamp was then lifted-off to peel away and transfer the gold films onto the stamp such that the films covered the air cavities while forming the top electrode of the MEMS device.
[0068] The primary aim of using acetone solvent in this process was to dissolve away the organic layer (TPD) such that the gold films were delaminated from the underlying transfer pad substrate and were free to transfer onto the patterned silicon-based substrate/any substrate. It is noted that acetone is exemplary and a variety of solvents that can dissolve and/or etch the organic release layer can be used interchangeably. Different organic compounds that can be dissolved by solvents other than acetone may also be used as the organic release layer on the transfer pad. These materials can be subsequently dissolved by using the appropriate solvent(s). Another release layer is supercritical carbon dioxide. The supercritical carbon dioxide can be used as a release layer that can vaporize upon being heated to room temperature or higher to delaminate and release the diaphragm to the MEMS structure. Other supercritical materials can also be used as the release layer. The release layer may also be photo- or heat-sensitive such that its exposure to radiation or heat would expedite its dissolution and/or dilution/erosion/etching/weakening/dissociation.
[0069] FIG. 8 shows photographs of two approximately 0.5″×0.5″ silicon substrates that are extensively covered in gold films transferred via the acetone-assisted contact transfer process. The yield (the area of gold picked-up and transferred per substrate) increases significantly due to the modification of transfer pad fabrication and spacer layer silanization parameters.
[0070] FIGS. 9 and 10 show examples of MEMS devices formed according to the release-assisted process of Example 1. Specifically, FIGS. 9 and 10 show a sensor array of about 1024 circular cavities covered by a gold diaphragm. The membrane was formed by the process of Example 1 and was about 140 nm thick. The underlying SiO 2 substrate comprised of cavities of 25-30 μm diameter, having a pitch distance of about 4-7 μm. The gold membrane can sink over some of the cavities during the fabrication process. The number of sunk cavities is dependent on the thickness of the dielectric spacer layer in the MEMS structure. In both FIGS. 9 and 10 portions of the diaphragm are collapsed over a region of the device.
[0071] The conductive membranes formed by the process of Example 1 were capable of deflecting and contorting repeatedly when a time-varying force or pressure was applied. The array demonstrated a repeatable gold membrane deflection of up to about 150-170 nm for 25-μm-diameter cavities by electrostatically actuating these devices at 15 V. The membranes were capable of being operated at lower and higher voltages, whether AC or DC, resulting in smaller or larger deflections. The deflection of these membranes has been confirmed with white light optical interferometry, as shown in FIGS. 11 and 12 .
[0072] FIG. 11 is the optical interferometry image of the gold diaphragm of Example 1. Here, SiO 2 array 1100 has a gold diaphragm overlay which can be used, among others, as a pressure sensor. The gold diaphragm above most sensor cavities 1110 shows about 150 nm of deflection at the cavities' center under 15 V DC actuation. The diaphragm at certain location in the array was irreversibly sunken due to repetitive testing at 40 V. These locations are shown as cavities 1120 in the array 1100 .
[0073] FIG. 12 shows the optical interferometry image of the gold diaphragm under AC actuation at different phase angles. Specifically, FIG. 12 shows optical interferometry images of several cavities when activated by an AC voltage of about 15 V peak-to-peak amplitude sinusoidal voltage actuation. The cavities are about 27 μm in diameter. Each of FIGS. 1210 , 1220 , 1230 , 1240 , 1250 , 1260 and 1270 were taken at 30° phase intervals. Thus, interferometry 1210 and 1220 are taken at 0° and 180°, respectively and show substantially no diaphragm deflection. Interferometry 1230 and 1240 correspond respectively, to 30° and 50° phases and show minimal deflections. Interferometry 1250 and 1260 correspond respectively, to 60° and 120° phases and show limited deflections. FIG. 12 shows that maximum deflection of the diaphragm occurs at the sinusoidal signal peak, i.e., when the phase is at 90°.
[0074] FIG. 13 is a 3D image of the deflected gold diaphragm due to an external bias. FIG. 13 was obtained using optical interferometry and shows a deflection of about 150 nm depth at the center of the active cavities. The array shown in FIG. 11 was biased with 15 V. The diameter of each cavity was about 27 μm.
[0075] FIGS. 14A-14C show large area diaphragms formed according to the disclosed embodiments. The photographs show large area gold membranes devices fabricated on cavity-patterned SiO 2 substrate via solvent-assisted contact-transfer printing with increased transfer pad curing time and spacer layer silanization time, increased silane concentration and increased silanization temperature. FIG. 14A shows a large area gold diaphragm covering about 16,000 cavities, each having diameter of about 27 μm, to form a single geometry device. FIGS. 14B and 14C show arrays of large area gold membranes each covering about 4,000 cavities each having 27 μm diameter.
[0076] FIG. 15 shows the deflection profile of a gold diaphragm at 15V bias obtained by optical interferometry. In FIG. 15 , the height of the diaphragm above the substrate was plotted against the radial distance across a single cavity. It can be readily seen that the deflection is highest at the center of the cavity.
[0077] FIGS. 16A-16C represent deflection profiles of diaphragms under electrostatic pressure. Namely, the figures show deflection profiles of gold diaphragm under electrostatic actuation. The data was obtained by optical interferometry. In FIG. 16A , deflection of the membrane increases as the voltage applied between the membrane and the Si substrate increases. In FIG. 16B , thirteen different diametrical deflection profiles (inset: interferometry image) of a membrane under 15 V actuation are plotted and averaged to show the mean profile. In FIG. 16C , gold membrane deflection over multiple cavities covered by a single membrane increases as the voltage is increased from 1 V to 15 V.
[0078] As stated, another technique for weakening the release layer is to expose the interim structure to solvent vapor. The solvent vapor acts as an etchant for the organic release layer. Using a solvent vapor is similar to the acetone-assisted contact-transfer printing process (see Example 1), except that acetone is not applied as a wet solvent to the transfer pad that has a diaphragm deposited atop a release layer. Instead, after depositing the conducting diaphragm over the release layer, the pick-up stamp (or the patterned silicon-based substrate) is brought into conformal contact with the transfer pad to form an interim structure. The interim structure is then placed in a chamber and is exposed to a solvent vapor. The vapor helps release the conducting membrane onto the MEMS. The advantage of this process over the direct dissolution is that it removes wet solvent processing. The chamber may also provide other energy sources for weakening the release layer. For example, the chamber may also heat the interim structure or expose it to radiation to break the adhesion between the diaphragm and the PDMS substrate. Thus, the release layer may be dissolved prior to removing the interim structure from the chamber. It should be noted that the release layer may be activated (i.e., weakened) prior to forming the interim structure.
[0079] In another embodiment, the diaphragm is transferred onto a MEMS structure by chemical surface treatment of the patterned silicon-based substrate. According to this embodiment, a thin continuous diaphragm is transferred onto a patterned silicon-based substrate by altering the chemical properties of the substrate (the MEMS structure). This can be done, for example, by silanizing the surface of the substrate using an appropriate silane compound to encourage adhesion between the substrate and the diaphragm. The silane compound functions as a double-sided tape, adhering to the substrate and the diaphragm enabling the membrane to delaminate from the transfer pad as the substrate is lifted away. By treating the substrates with the appropriate silanes (e.g., phenyl ethyl trichlorosilane or 3-mercaptopropyltrimethoxysilane) transfer of monolayer or multiple layers of graphene or molybdenum disulfide onto silicon-based substrates is also feasible. The silane treatment method can also be used to enhance/enable the transfer of metal membranes as well, such as gold, silver, aluminum or combinations thereof. The chemical surface treatment of silicon-based substrates can also be used together with the solvent-assisted transfer of conductive membranes in order to ensure a better adhesion of the diaphragm to the silicon-based substrates. The chemical surface treatment method/silanization method could be used independent of any of the release-layer dissociation methods discussed earlier or in combination therewith.
[0080] The methods disclosed herein can be used to fabricate a wide variety of MEMS sensors, actuators and devices. Exemplary MEMS devices include pressure sensors, noise-cancelling headphones, high fidelity earphones, microphones, micro-pumps, speakers, hearing aids, ultrasound transducers, electrically-texture-adaptive surfaces, haptic feedback screens/surfaces, tunable lasers, and the large-area arrays of these sensors and actuators. Particularly suitable applications for deposition methods provided herein are array type sensors and actuators where a group of sensors/actuators can be activated independently. For example, a large array of actuators can be formed using the release-assisted method. A programmable controller having a microprocessor circuit in communication with a memory circuit can be configured to activate portions of the array depending on the actuation level.
[0081] Moreover, the disclosed processes can be used to generate multiple devices in a small spatial footprint. Multiple sensors/actuators or high sensor/actuator density is necessary for multiple applications, such as high quality earphone sound, spatially-resolved pressure sensing for structural integrity and wind tunnel testing, and phased array acoustic imaging. Since the MEMS sensors and actuators are typically capacitive in design, device power consumption is significantly lower which prolongs battery life.
[0082] FIG. 17 shows an exemplary microprocessor-controlled array according to one embodiment of the disclosure. In FIG. 17 , MEMS device 1710 includes a number of cavities or pixels covered by diaphragm 1716 . Cavities/pixels 1712 and 1714 define a first group and a second group of cavities, respectively. MEMS device 1710 communicates with controller 1730 either directly or through actuator 1720 . Actuator 1720 may also define a sensor. Controller 1730 is shown with processor circuit 1732 in communication with memory circuit or database 1734 . Controller 1730 also communicates with interface 1770 which can be any device capable of external communication (e.g., display, keyboard, etc.)
[0083] In an embodiment where MEMS device 1710 is implemented as a sensor, diaphragm 1716 is exposed to external or ambient energy which causes deflection of the diaphragm. The deflection can be communicated to controller 1730 , which in-turn correlates the reported deflection to a quantifiable force. The detection can be made across the entire array of cavities/pixels or over a specified region. For example, the controller may report that ambient forces were detected in regions identified by group of cavities/pixels 1712 and/or 1714 . Alternatively, controller 1730 may report varying forces detected across all cavities/pixels of device 1710 . In this implementation, controller 1730 can correlate the location of detected energy with its corresponding magnitude.
[0084] In an embodiment where MEMS device 1710 is implemented as a transducer, controller 1730 identifies the cavities/pixels that need to be activated and the amount of desired deflection in each ones or groups of cavities/pixels. Here, the controller communicates the location and the desired activation bias to actuator 1720 . The actuator may communicate the force to a voltage source (not shown) which would bias the desired cavity(ies) or pixel(s) accordingly. It should be noted that one or a plurality of cavities can be controlled in this manner. Alternatively, the entire MEMS device may be activated at one time. Moreover, different cavities can be activated with difference biases to produce a desired deflection.
[0085] While the principles of the disclosure have been illustrated in relation to the exemplary embodiments shown herein, the principles of the disclosure are not limited thereto and include any modification, variation or permutation thereof.
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The disclosure provides methods and apparatus for release-assisted microcontact printing of MEMS. Specifically, the principles disclosed herein enable patterning diaphragms and conductive membranes on a substrate having articulations of desired shapes and sizes. Such diaphragms deflect under applied pressure or force (e.g., electrostatic, electromagnetic, acoustic, pneumatic, mechanical, etc.) generating a responsive signal. Alternatively, the diaphragm can be made to deflect in response to an external bias to measure the external bias/phenomenon. The disclosed principles enable transferring diaphragms and/or thin membranes without rupturing.
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CROSS REFERENCE TO RELATED APPLICATIONS
This patent application claims the benefit of United States of America Provisional Patent Application U.S. 61/893,415 filed Oct. 21, 2013 entitled “Methods and Systems Relating to AC Current Measurements.”
FIELD OF THE INVENTION
This invention relates generally to precision AC measurements, which include precision AC current, voltage, phase, impedance, frequency, power and energy measurements, in the current range from 1 mA or less to 20 kA or greater and voltage range of 1V or less to 1000 kV or greater and in a frequency range from a few hertz to one hundred kilohertz. In particular it relates, but is not limited to AC measurements as applicable in power transmission and distribution networks.
BACKGROUND OF THE INVENTION
The accurate Alternating Current (AC) measurement of electrical power at various points of a power grid is becoming more and more important and, at the same time, is getting more and more difficult. The old power distribution model of a few, large power generating stations and a multitude of relatively linear loads is being replaced by a newer model containing a multitude of smaller, and to some degree unpredictable power sources, as well as a multitude of not always linear and often smart (essentially also unpredictable) loads. This change deteriorates power quality and makes AC measurements, grid management and troubleshooting more difficult. Also, the increasing cost of electrical power makes precise calculation of delivered energy and monitoring of power quality important.
There are three main categories of AC power measurement systems: The highest level of accuracy systems, used typically by the Standard and Calibration Laboratories, are developed to reference measurement to the National Standards. These are typically unique installations, not covered by specific regulatory requirements. The next category is high precision AC power measurement systems. In the important case of AC power measurement instruments, usually referred to as Power Analyzers, these would be units meeting the requirements of standards, such as for example International Standard IEC 61000-4-30 “Electromagnetic Compatibility: Part 4-30 Testing and Measurement Techniques—Power Quality Measurement Methods” which relates to Class A measurement methods. These are used where precise measurements are necessary, for example for contractual applications and disputes, verifying compliance with standards, etc. Two different Class A instruments, when measuring the same quantities, should produce matching results within the specified uncertainty for that parameter. The third main category of the AC power measurement system is general use instruments. Generally it is recommended that this group reflect measurement methods and intervals of Class A instruments, with lower precision and processing requirements. It is then classified as Class S. Other instruments including legacy installations, whose operation doesn't reflect methods of Class A, but still meet key accuracy requirements, are summarily called Class B. Irrespective of the class of the AC power measurements they require determination of the voltage, current, frequency, phase, and relative timing of the single or multiple phases of the power system in order to perform the measurements.
The whole measurement chain of electrical quantity for power analysis consists of measurement transducer, measurement unit and evaluation unit (as is defined in the ICE 61000-4-30 standard). The measurement transducer converts the input quantity to a level and a kind suitable for the measurement unit and typically has some other functionality, for example signal isolation or overload protection. For example, the measurement transducer may reduce a power line voltage of hundreds of kilovolts to tens of volts. The measurement unit then converts the input quantity, typically to a digital form, suitable for evaluation. Then the evaluation unit, which is typically some form of a computing device, receives and combines data streams from different input channels including for example the output of the measurement unit and a reference unit, and does the required calculations to produce results. Test results can be: recorded, aggregated, automatically evaluated in the real time, displayed on the instrument screen, used to generate alarms, placed in system logs, and send out for external evaluation and storage, etc.
Generally, AC electrical measurements are used in a wide variety of applications and may be performed for a variety of electrical quantities including voltage, current, capacitance, impedance, resistance etc. These tests and measurements include those relating to designing, evaluating, maintaining and servicing electrical circuits and equipment from high voltage electrical transmission lines operating at hundreds of kilovolts (kV) and kiloamps (kA) to industrial/medical/residential electrical and lighting, typically 400V/240V/100V and 30/15 A, to a wide variety of industrial/scientific/medical/consumer electrical and electronic devices.
Within a variety of applications and test equipment systems the measurement transducer is often a toroidal transformer. These allow for the measurement system to measure the required parameter(s) with the measurement system electrically isolated from the electrical system being measured. Further, toroidal forms of the core of the transformer provide best magnetic performance of the core, providing low magnetic reluctance, good uniformity of the magnetic field and low flux leakage, resulting in the best electrical parameters of the transformer. In general, the toroidal form of the core of the transformer is an accepted standard for meteorological applications.
However, with the continued drive for improved accuracy in calibration, standards, and measurements on circuits and components operating at hundreds of kiloVolts, thousands of Amps, with resistances into Gigaohms accuracies of parts per million is being replaced by parts per billion. At the same time as discussed supra such measurements are being performed upon, for example, electrical power distribution systems at various points of a power grid with a variety of generators, distribution systems, etc. with unknown or variable characteristics. On the other hand even the best toroidal core transformers still have three basic limitations, affecting performance of the transducer, namely saturation of the core, finite value of the permeability and finite width of the hysteresis loop. Each one affects operation of the transformer and may limit overall accuracy of the resulting transducer. The first and most obvious way to improve performance of the measurement transformer is to use highest permeability, lowest losses (narrowest hysteresis loop) magnetic materials for the core.
Next, the inventors have established a measurement and correction methodology for AC current transducers designing multi-core, multi-stage transformers compensating effects of finite, changing burden. Similarly, DC compensation was introduced to improve AC operation of the measurement transformer in the presence of the DC components magnetizing the transformer core. Beneficially, such measurement and correction methodologies provide instrument designers with multiple options ranging from low cost alarms through to higher cost automated correction hardware software and firmware based circuits.
Such measurement and correction methodologies would beneficially allowed such devices according to some embodiments of the device to achieve performance approaching that of reference measurements operating in laboratory conditions. It would be further beneficial if the same principles provide power utilities, independent electricity producers, electrical engineers and technicians, and others requiring accurate measurements of power systems with a field deployable power system measurement devices providing up to Class A type performance but in rugged devices of reduced cost and complexity.
Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide measurement and correction methodologies for DC currents within precision AC measurement instruments, which include precision AC current, voltage, phase, impedance, frequency, power and energy instruments, operating in the current range from 1 mA or less to 20 kA or greater and voltage range of 1V or less to 1000 kV or greater and in a frequency range from a few hertz to one hundred kilohertz. In particular the invention relates to, but is not limited to AC measurements as applicable in power transmission and distribution networks.
In accordance with an embodiment of the invention there is provided a method comprising measuring a DC signal, the DC signal generated in dependence upon a DC aspect of a signal, measuring an AC signal, the AC signal generated in dependence upon an AC aspect of the signal, and generating a corrected measurement of the measured AC signal.
In accordance with an embodiment of the invention there is provided a device comprising:
a dual stage current transformer comprising a plurality of magnetic cores, a primary winding, a first secondary winding, and a second secondary winding; a first resistor coupled across the first secondary winding generating a first voltage; a second resistor coupled across the second secondary winding disposed in series with the first resistor to add a compensating voltage to the first voltage; a DC magnetic sensor coupled to a first magnetic core of the plurality of magnetic cores for generating a signal proportional to a DC magnetic field within the dual stage current transformer; and a flux compensation winding coupled to a second magnetic core of the plurality of magnetic cores for generating a magnetic flux to reduce the DC magnetic field within the dual stage current transformer.
In accordance with an embodiment of the invention there is provided a method comprising using a DC magnetic sensor and flux compensation in conjunction with a dual stage current transformer, wherein the dual stage transformer uses resistors to add voltages rather than adding currents.
In accordance with an embodiment of the invention there is provided a method comprising integrating a magnetic sensor within a magnetic core of a plurality of magnetic cores within a dual stage current transformer allowing operation of the sensor with small AC flux components and improved AC to DC signal ratio.
In accordance with an embodiment of the invention there is provided a device comprising a dual stage current transformer comprising a plurality of magnetic cores, a primary winding, a first secondary winding, and a second secondary winding and a DC magnetic sensor coupled to a first magnetic core of the plurality of magnetic cores for generating a signal proportional to a DC magnetic field within the dual stage current transformer.
In accordance with an embodiment of the invention there is provided a device comprising a current comparator comprising a magnetic core, a primary winding wound around the magnetic core, a secondary winding wound around the magnetic core, and a magnetic sensor coupled to a magnetic field generated in dependence upon a first current within the primary winding and a second current within the secondary winding, wherein the primary and secondary windings are wound around the magnetic core directly without a magnetic shield disposed between any of the magnetic core, the primary winding, and the secondary winding.
In accordance with an embodiment of the invention there is provided a current comparator based sensor comprising:
a magnetic core; a primary winding wound around the magnetic core for connecting to an electrical circuit; a secondary winding wound around the magnetic core; a magnetic sensor coupled to the magnetic field within the magnetic core; a control circuit for generating and applying a magnetization current to at least one of the primary winding and a tertiary winding wound around the magnetic core, wherein the magnetization current sequentially cycles the magnetic core to saturation in opposite directions; and a measurement circuit coupled to at least the secondary winding for determining timing information relating to the cycling of the magnetic core and establishing a magnetization field strength therefrom and the current flowing in the primary winding due to the electrical circuit.
In accordance with an embodiment of the invention there is provided a current comparator comprising:
a magnetic field sensor; a primary winding for connecting to an electrical circuit disposed either above or around the magnetic field sensor; and a secondary winding for generating a current to be employed in determining a current flowing within the electrical circuit disposed below the magnetic field sensor when the primary winding is disposed above and around the magnetic field sensor between the primary winding and the magnetic field sensor when the primary winding is around the magnetic field sensor.
Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention will now be described, by way of example only, with reference to the attached Figures, wherein:
FIGS. 1 and 2 depict the measurement ratio, I/I 0 of toroidal single stage and dual stage AC current transformers with varying DC current expressed in ampere-turns (AT);
FIG. 3 depicts a current sensing circuit for a measurement probe according to the prior art of U.S. Pat. No. 7,309,980 for a single core transformer;
FIG. 4 depicts a transformer correction approach according to the prior art of U.S. Pat. No. 7,348,845 for a single core transformer;
FIG. 5 depicts Hall current sensor circuit configurations according to an embodiment of the invention;
FIG. 6 depicts a dual stage driver circuit for a Hall current sensor according to an embodiment of the invention;
FIG. 7 depicts a single stage driver circuit for a Hall current sensor according to an embodiment of the invention;
FIG. 8 depicts a two-stage current transformer and associated electrical interface circuit according to an embodiment of the invention;
FIGS. 9A-9C depict schematically electrical circuits of multi-core current transformers according to embodiments of the invention;
FIGS. 10A-10C depict schematically electrical circuits of multi-core current transformers according to embodiments of the invention;
FIG. 11 depicts a two stage current transformer according to an embodiment of the invention which when resistively connected as described in FIG. 10A provides an implementation of a single stage, Current Transducer with Hall sensor based DC flux detection;
FIG. 12 depicts a two stage current transformer according to an embodiment of the invention utilizing third core for the DC bias detection core which when resistively connected as described in FIG. 10A provides an implementation of a two stage Current Transducer with Hall sensor based DC flux detection;
FIG. 13 depicts a dual stage current transformer according to an embodiment of the invention with a magneto-strictive element positioned on the shield which when resistively connected as described in FIG. 10A provides an implementation of the Current Transducer;
FIG. 14 schematically an electrical circuit of a multi-core current transformer according to an embodiment of the invention; and
FIG. 15 depicts a two stage current transformer according to an embodiment of the invention utilizing a third core for the DC bias detection core which when resistively connected as described in FIG. 14 provides an implementation of a two stage Current Transducer with DC flux detection using fluxgate detectors and Hall sensor;
FIG. 16 depicts a current comparator according to the embodiment of the invention, utilizing a flux gate detector to detect input and output current—turn balance wherein the prior art magnetic shield between the magnetic sensor and the primary and secondary windings is removed;
FIGS. 17A and 17B depict a current comparator according to the embodiment of the invention utilizing Hall Effect magnetic sensors to detect input and output current—turn balance wherein the prior art magnetic shield between the magnetic sensor and the primary and secondary windings is removed; and
FIG. 18 depicts an active current to current transducer according to the embodiment of the invention utilizing current comparator with a magnetic sensor and an amplification block to produce AC and DC output current in precise ratio to the input current.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
This invention relates generally to precision AC measurements, which include precision AC current, voltage, phase, impedance, frequency, power and energy measurements, in the current range from 1 mA or less to 20 kA or greater and voltage range of 1V or less to 1000 kV or greater and in a frequency range from a few hertz to one hundred kilohertz. In particular it relates, but is not limited to AC measurements as applicable in power transmission and distribution networks.
The ensuing description provides exemplary embodiment(s) only, and is not intended to limit the scope, applicability or configuration of the disclosure. Rather, the ensuing description of the exemplary embodiment(s) will provide those skilled in the art with an enabling description for implementing an exemplary embodiment. It being understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope as set forth in the appended claims.
Precise AC power measurements require precise determination of the voltage, current and timing of the single or multiple phases. However, as evident in FIGS. 1 and 2 the ratio of a measured AC current, I, with varying DC current relative to the measured AC current, I 0 , at no DC current is not equal to one, i.e. I/I 0 =1, with varying DC current but varies substantially with DC current and magnitude of the AC current being measured. For an applied AC current of 510 A the ratio exceeds 1.01 at approximately 1 ampere turn (AT). This represents an error of 1% or 10,000 parts per million or 10 million parts per billion. Accordingly, when considering test instrumentation providing accuracies of a few parts per million it is evident that poor signal conditioning of the signal being measured will result in errors that dwarf those from the measurement instrument itself. Clearly significant control of the DC current is required in order to achieve the intrinsic accuracy of the test instrument.
Within the prior art techniques these have been techniques presented to combine AC and DC current sensing. One such example is presented within FIG. 3 according to the prior art of Mende et al in U.S. Pat. No. 7,309,980 for a single core transformer in respect of current sensing circuit for a measurement probe. As depicted, there is a ring-shaped core 312 of magnetic material defining an aperture. A current carrying conductor 314 is coupled in a flux linking relationship with ring-shaped magnetic core 312 . The current carrying conductor 314 is preferably linked to the ring-shaped magnetic core 312 via a multi-turn primary winding 316 that is coupled in series with the current carrying conductor 314 . Alternately, the current carrying conductor 314 may be inserted through the aperture in the ring-shaped magnetic core 312 and act as the primary winding 316 . The current to be measured in the current carrying conductor 314 produces a magnetic flux in the magnetic core 312 and is linked to a multi-turn secondary winding 318 . One terminal of the secondary winding 318 is coupled to ground with the other terminal being coupled to the inverting input terminal of a transimpedance amplifier 320 . The inverting input terminal of the transimpedance amplifier 320 is coupled to the output terminal of the amplifier 320 via a current signal path 322 having a transimpedance resistor 324 . Thus the primary winding 316 or alternately the current carrying conductor 314 , the magnetic core 312 and the secondary winding 318 function as a transformer 326 . A magneto-electric converter 328 is disposed within the magnetic core 312 substantially perpendicular to the lines of flux in the magnetic core 312 . The magneto-electric converter 328 is preferably a thin film semiconductor Hall effect device having a first pair of terminals coupled to a bias source 330 and a second pair of terminals connected to differential inputs of amplifier 332 . In an embodiment of the invention, the amplifier 332 is a high gain differential amplifier having low noise and high common mode rejection the single ended output of the differential amplifier 332 is coupled to the non-inverting input of the transimpedance amplifier 320 . Accordingly, the transimpedance amplifier 320 functions as a power amplifier for DC to low frequency current signals and a transimpedance gain amplifier for higher frequency signals. In this manner the overall circuit acts as a DC to high frequency current probe but no correction of the AC portion of the circuit for DC currents is considered.
Referring to FIG. 4 there is depicted a transformer correction approach according to the prior art of Giovannotto in U.S. Pat. No. 7,348,845 for a single core transformer. As depicted the system comprises an amplifier 410 and variable magnetic flux bias system 450 . Amplifier 410 comprises amplifier circuitry 420 , amplifier signal line 425 , output transformer 430 , primary winding 432 , secondary winding 434 , control winding 480 , and optionally load 440 . Amplifier 410 receives input signals from signal source 405 , and provides amplified output signals to load 440 . Variable magnetic flux bias system 450 comprises magnetic sensor 460 , flux signal line 465 , control circuitry 470 , and control signal line 475 .
Amplifier circuitry 420 may be any audio amplifier known in the prior art that uses an output transformer, such as output transformer 430 , and may comprise vacuum tubes in a triode, tetrode, or pentode configuration, or may comprise solid state devices. Amplifier circuitry 420 may be operated in bias modes including, but not limited to, Class A, Class AB(1), Class AB(2), Class B, Class C, or Class D.
Variable magnetic flux bias system 450 uses magnetic sensor 460 to sense a first magnetic flux in the proximity of output transformer 430 . The first magnetic flux is a portion of the leakage magnetic flux emanating from output transformer 430 . Magnetic sensor 460 may be a linear-output Hall-Effect sensor. In other embodiments, magnetic sensor 460 may include, but is not limited to a magnetoresistive sensor, a fluxgate sensor, a superconducting quantum interference device (SQUID) sensor, or an electron-spin sensor.
By placing magnetic sensor 460 in proximity to output transformer 430 , the first magnetic flux of output transformer 430 may be sensed, generating a flux signal on flux signal line 465 . The first magnetic flux has components representing a portion of the total magnetic flux within the transformer, comprising both the desired higher-frequency amplifier signal from signal source 405 and the undesired DC and low-frequency subsonic components.
Flux signal line 465 is coupled to control circuitry 470 . Control circuitry 470 is configured to receive the flux signal from flux signal line 465 and to generate a control signal on control signal line 475 representing the undesired DC and low-frequency subsonic components of the first magnetic flux of output transformer 430 .
Control winding 480 is coupled to control circuitry 470 via control signal line 475 , and thereby receives the control signal. Using the received control signal, control winding 480 induces a second magnetic flux in output transformer 430 that may set a non-zero quiescent magnetic bias level in output transformer 430 . Alternatively, control circuitry 470 may generate a control signal that causes control winding 480 to induce a second magnetic flux that substantially cancels out or nulls the undesired DC and low-frequency subsonic components of the first magnetic flux in output transformer 430 . Control winding 480 may be a spare or unused winding in output transformer 430 , or may be added after output transformer 430 is manufactured. Control winding 480 may be a primary winding or a secondary winding of output transformer 430 . Control winding 480 may be multiple individual windings coupled to control signal line 475 .
In one embodiment, control circuitry 470 may be adjusted so that a quiescent magnetic bias level is maintained within output transformer 430 . The quiescent magnetic bias level may be maintained at a level different from zero. In another embodiment, control circuitry 470 may be adjusted so that the second magnetic flux substantially cancels or nulls out the DC and low-frequency subsonic components of the first magnetic flux, and thus minimizes the magnetic saturation within output transformer 430 . Control circuitry 470 may be implemented using operational amplifiers, or alternatively using a proportional integral (PI) or proportional-integral-derivative (PID) control loop comprising a digital signal processor or microcontroller.
Referring to FIG. 5 there is depicted a Hall sensor circuit board according to an embodiment of the invention wherein first and second Hall sensors Hall # 1 510 and Hall # 2 520 respectively which detect opposite sense magnetic fields, (+) and (−) respectively. As depicted in FIG. 5 , each Hall sensor is connected to +5V and GND power supply rails and generates an output signal coupled to output ports 530 A and 530 B respectively for (+) and (−) field directions respectively. Whilst a pair of Hall sensors are depicted a single Hall sensor, or multiple hall sensors may also be employed. Similarly, non-differential configurations of a pair of Hall sensors may also be employed.
In each the Hall sensors are inserted within holes in the circuit board in order to reduce the vertical dimensions of the Hall sensor circuit board as this impacts the performance of the magnetic core of the transformer within which it is to be inserted as minimizing the profile of the sensor/circuit board reduces the size of the slot that has to be cut into the core of the current transformer transducer. Surrounding the Hall sensor devices and the circuit board which is inserted into the transformer core is a protective film or layer which may be wrapped, such as in the example of using a protective film or tape or deposited such as for example by dip coating. The circuit board may be formed from one or more standard circuit materials known within the prior art including, but not limited to, FR-4, FR-6, CEM-3, CEM-4, G-10, alumina, and aluminum nitride. It would be evident that other circuit board designs may be employed as well as that the number and orientation of the Hall effect sensors may be varied together with their integration into different numbers of packages. For example, a custom Hall sensor package may employ 4 Hall effect sensors orientated at right angles to one another with 2 measuring (+) fields within the core and the others measuring (−) fields within the core relative to the sensors. Similarly, placement may be adjusted in respect of the design of the core. Beneficially pre-packaged sensors allow for pre-screened components in hermetic packages if appropriate although non-hermetic and discrete die options may be considered as well as a discrete ceramic package having internally the sensors and appropriate circuit tracks.
Now referring to FIG. 6 there is depicted a dual-stage driver circuit for use in conjunction with first and second Hall sensors Hall # 1 610 and Hall # 2 620 respectively according to an embodiment of the invention. As depicted two operational amplifiers (op-amps) such as Texas Instruments THS4521 Fully-Differential Amplifiers are employed with an output generated across output resistor RI in proportion to the field measured. FIG. 7 depicts a corresponding single stage driver according to an embodiment of the invention.
Referring to FIG. 8 there is depicted an exemplary circuit according to an embodiment of the invention to generate a digital representation of an input analog signal applied across the L and N terminals 800 A and 800 B respectively. As depicted a current transformer (CT) 810 with primary winding of N 0 turns is coupled to the L and N terminals 800 A and 800 B. A first secondary winding of N 1 turns is coupled to a first load resistor, R LOAD1 =50Ω and a second secondary winding of turns is coupled across a second load resistor, R LOAD1 =50Ω, which is serially connected to the first load resistor. The outer connections of the first and second load resistors are coupled to the + and − inputs of a differential operational amplifier (OpAmp) 820 via resistors, R A =100 KΩ. The differential outputs of the differential OpAmp 820 are each fed back via feedback resistors R B =50 kΩ and coupled via anti-aliasing circuitry to ADC 830 , such as for example an Analog Devices ADS1271 which provides a 24-bit delta-sigma analog-to-digital converter (ADC) at 105 kSPS and 51 kHz bandwidth. The ADC 830 output is coupled to output 800 D. The reference voltage, ADC 830 power, and differential OpAmp 820 power are supplied via third input 800 C, +V IN .
Now referring to FIG. 9A there is depicted an embodiment of a Current Transducer (CT) 900 according to the prior art exploiting a dual-stage design wherein the signal induced within a first secondary windings N 1 has a corrective signal applied which is generated by second secondary winding N 2 . CT 900 being a dual stage CT without DC bias compensation. CT 900 consists of a dual stage current transformer CT R 929 containing primary winding N 0 and first and second secondary windings N 1 and N 2 respectively. The Current Transducer 929 primary input terminal I IN is connected to the start connection of the primary winding N 0 , while the end connection of N 0 is connected to the primary output terminal I OUT . An electrical shield S 930 is placed between the primary and the secondary sides and connected to a dedicated shield terminal Sh 900 C. Winding N 1 is loaded with a precise resistance R 1 931 and second stage winding N 2 is loaded with a precise resistance R 2 932 . The High output terminal H 900 A of the Current Transducer 900 is connected to the start connection of secondary winding N 1 , while the end connection of winding N 1 is connected to the start connection of second stage winding N 2 . End connection of second stage winding N 2 is connected to the Low output terminal L 900 B of the transducer. Accordingly, current passing through the primary winding N 0 produces a proportional voltage between output terminals H 900 A and L 900 B wherein the winding N 1 /precise resistance R 1 931 combination provides a correction current applied to that generated by second stage winding N 2 /precise resistance R 2 932 . The High and Low output terminals H 900 A and L 900 B together with shield terminal Sh 900 C are coupled to processing circuit 930 .
Optionally a switchable resistor, i.e. a resistor switchable into the circuit or selectable between a first fixed resistance value and no resistance, is coupled between the winding N 1 and point A during manufacturing testing. Accordingly, if a variation in the signal at the H and L terminals 1000 A and 1000 B is measured for constant input when the switchable resistor is toggled between its two states then the polarity of the correction circuit is incorrect in assembly. Accordingly, as discussed supra in respect of FIGS. 1 and 2 DC currents on the input side will impact the measurements such that an incorrect AC current will be measured. Referring to FIGS. 9B and 9C two simple embodiments of DC current sensing are depicted wherein in FIG. 9B first circuit 900 D includes a Shunt R S 934 allowing a measurement of the DC current to be made thereby allowing, for example, an alarm to be triggered when the DC current exceeds a predetermined threshold. However, this DC offset may be difficult to observe and the Shunt R S 934 may limit the operating range of the measurement instrument including first circuit 900 D to provide the Current Transducer. In second circuit 900 E a Hall effect sensor 935 is added to monitor the input to primary winding N 0 and provide sensing of any DC current present on the input. Whilst this removes the loading issue of first circuit 900 D the Hall effect sensor 935 induces an inherent offset that must be accounted for and corrected for. Depending upon conductor design to the primary winding N 0 a configuration such as presented within the prior art of Seitz in U.S. Pat. No. 4,749,939 may be employed for example. Rather than a Hall effect sensor 935 a Flux Gate Detector (FGD) may be employed but these have the drawback that they operate with AC signals themselves, typically at 700-800 Hz and thereby generate noise within the second circuit 900 E.
Now referring to FIGS. 10A and 10B there are depicted first and second circuit schematics 1000 A and 1000 B depicting variants of the Current Transducer (CT) according to an embodiment of the invention. The CT now consists of a dual stage current transformer CT R 1050 A containing primary winding N 0 and first and second secondary windings N 1 and N 2 respectively together with an electrical shield S 930 placed between the primary and the secondary sides and connected to a dedicated shield terminal Sh 900 C. First secondary winding N 1 is loaded with a precise resistance R 1 931 and second secondary winding N 2 is loaded with a precise resistance R 2 932 . The High output terminal H 900 A of the Current Transducer 1000 A is connected to the start connection of secondary winding N 1 , while the end connection of winding N 1 is connected to the start connection of second stage winding N 2 . End connection of second stage winding N 2 is connected to the Low output terminal L 900 B of the transducer. Accordingly, current passing through the primary winding N 0 produces a proportional voltage between output terminals H 900 A and L 900 B wherein the winding N 1 /precise resistance R 1 931 combination provides a correction current applied to that generated by second stage winding N 2 /precise resistance R 2 932 .
In first circuit 1000 A, unlike CT R 929 in FIG. 9A , the CT R 1050 A now has a Hall sensor 1010 embedded within it which couples via Magnetic Field (MF) 1040 A to Processing Circuit 1020 which also receives the output from the modified CT R 929 . Accordingly, Processing Circuit 1020 may determine in some embodiments of the invention that the DC current is beyond a threshold established in dependence, for example, upon the magnitude of the AC current and the desired accuracy of the AC current reading. Accordingly, a measurement instrument may allow coarse low accuracy measurements on poorly conditioned input signals but prevent high accuracy measurements until the input signal has been conditioned to the required degree.
In second circuit 1000 B ( FIG. 10B ), unlike the CT R 929 in FIGS. 9A through 9C and CT R 1050 A in FIG. 10A , the CT R 1050 B now has a Hall sensor 1010 and a tertiary winding 1070 . The Hall sensor 1010 is embedded within the CT R 1050 B and couples via Magnetic Field (MF) 1040 A to Processing Circuit 1030 which also receives the output from the modified CT R 1050 B. Accordingly, Processing Circuit 1020 generates a correction current which is coupled to a tertiary winding 1070 with N 3 turns also coupled to the CT R 1050 B. Accordingly, the Processing Circuit 1030 now generates a current in dependence upon the measured DC field from Hall sensor 1010 and number of turns N 3 in order to generate within the CT R 1050 B a field negating or reducing the DC field present within the CTR 1050 B as a result of the conditioning or lack of conditioning applied to the input signal being analyzed.
Referring to FIG. 10C there is a third circuit 1000 C which is very similar to second circuit 1000 B except that in addition to the tertiary winding N 3 coupled to the CT R 1050 C there is a quaternary winding N 4 coupled together with the second secondary winding N 2 , these being upon a different core of the Current Transducer to that of the first secondary winding N 1 and tertiary winding N 3 , Tertiary winding N 3 and quaternary winding N 4 provide Correction Winding 1 1070 and Correction Winding 2 1060 for the two cores of the Current Transducer. Accordingly, corrective magnetic fields may be induced if necessary in multiple cores of a Current Transducer.
According to the design of the Current Transducer that the Hall sensor 1010 may be embedded into one core of a plurality of cores or alternatively multiple Hall sensors 1010 may be embedded such that a Hall sensor 1010 is disposed within each core of the Current Transducer or a predetermined subset of the cores of the Current Transducer.
Referring to FIG. 11 there is depicted a Current Transducer according to an embodiment of the invention such as described supra in respect of Current Transducer (CT) 1000 A in FIG. 10A exploiting a dual-core transformer architecture. Accordingly, first image 1100 A depicts the CT sequentially stripped from the outermost layer towards the centre whilst second image 1100 B depicts a three dimensional quarter-cut sectional view with first to fifth tape layers 1130 A through 1130 E respectively and shielding 1160 . Accordingly, as shown the CT comprises first and second cores 1110 and 1120 respectively. First core 1110 has embedded within it Hall sensor 1180 . Second core 1120 then has first tape layer 1130 A separating the first winding 1140 from it which is then overwound with second tape layer 1130 B. The first and second cores 1110 and 1120 with their respective surrounding layers are then overwound with third tape layer 11300 . Atop third tape layer 1130 C second winding 1150 is wound around both the first and second cores 1110 and 1120 respectively. Second winding 1150 is then overwound by fourth tape layer 1130 D, shielding 1160 , fifth tape layer 1130 E and third winding 1170 . As depicted first winding 1140 corresponds to second secondary winding N 2 of FIG. 10A , second winding 1150 corresponds to first secondary winding N 1 of FIG. 10A , and third winding 1170 corresponds to the primary winding N 0 of FIG. 10A . Optionally a second shielding may be disposed between the first and second windings 1140 and 1150 respectively such as between second and third tape layers 1130 B and 1130 C respectively.
Second image 1100 B depicts a three dimensional quarter-cut sectional view with first to fifth tape layers 1130 A through 1130 E respectively and shielding 1160 removed thereby showing how the first to third windings 1140 , 1150 and 1170 respectively are wound around the closed magnetic elements forming the first and second cores 1110 and 1120 respectively. Also depicted within first core 1110 is Hall sensor 1180 , for example, within a slot machined within the closed magnetic element forming first core 1110 . It would be evident to one skilled in the art that the number of windings for each of the first to third windings 1140 , 1150 , and 1170 respectively and geometries of the first and second cores 1110 and 1120 respectively may be adjusted according to the electrical voltage, current and power of the signal being measured and design of the Asynchronous Power Measurement System within which the Current Transducer forms part. Accordingly, a Hall sensor such as described supra in respect of FIG. 6 , and other variants not depicted, may be inserted into the first core 1110 as depicted or alternatively second core 1120 in order to provide the determination and/or management of a DC field within the Current Transducer. Optionally, multiple Hall sensors 1180 may be embedded into one or more cores.
Referring to FIG. 12 there is depicted a Current Transducer according to an embodiment of the invention such as described supra in respect of Current Transducer (CT) 1000 A in FIG. 10A employing a three core transformer architecture. Accordingly, first image 1200 C depicts the CT sequentially stripped from the outermost layer towards the centre whilst second image 1200 D depicts a three dimensional quarter-cut sectional view with first to fifth tape layers 1230 A through 1230 E respectively and shielding 1260 . Accordingly, as shown the CT comprises first, second, and third cores 1210 A, 1220 , and 1210 E respectively. Second core 1220 then has first tape layer 1230 A separating the first winding 1240 from it which is then overwound with second tape layer 1230 B. The first, second, and third cores 1210 A, 1220 , and 1210 B respectively with their respective surrounding layers are then overwound with third tape layer 1230 C. Atop third tape layer 1230 C second winding 1250 is wound around first, second, and third cores 1210 A, 1220 , and 1210 B respectively. Second winding 1250 is then overwound by fourth tape layer 1230 D, shielding 1260 , fifth tape layer 1230 E and third winding 1270 . As depicted first winding 1240 corresponds to second secondary winding N 2 of FIG. 10 , second winding 1250 corresponds to first secondary winding N 1 of FIG. 10 , and third winding 1270 corresponds to the primary winding N 0 of FIG. 10 . Optionally, a second shielding may be disposed between the first and second windings 1240 and 1250 respectively such as between second and third tape layers 1230 B and 1230 C respectively. Embedded within third core 1210 B is Hall sensor 1280 .
Second image 1200 D depicts a three dimensional quarter-cut sectional view with first to fifth tape layers 1230 A through 1230 E respectively and shielding 1260 removed thereby showing how the first to third windings 1240 , 1250 and 1270 respectively are wound around the closed magnetic elements forming the first, second, and third cores 1210 A, 1220 , and 1210 B respectively. Also depicted within second image 1200 D is Hall sensor 1280 which may be inserted into a slot machined within the third core 1210 B. It would be evident to one skilled in the art that the number of windings for each of the first to third windings 1240 , 1250 , and 1270 respectively and geometries of the first, second, and third cores 1210 A, 1220 , and 1210 B respectively may be adjusted according to the electrical voltage, current and power of the signal being measured and design of the Asynchronous Power Measurement System within which the Current Transducer forms part. Accordingly, a Hall sensor 1280 such as described supra in respect of FIG. 6 , and other variants not depicted, A through 6 C and FIGS. 11A through 11C may be inserted into the first, or the third core 1310 A, or 1310 B in order to provide the determination and/or management of a DC field within the Current Transducer.
Referring to FIG. 13 there is depicted a Current Transducer according to an embodiment of the invention such as described supra in respect of Current Transducer (CT) 1000 in FIG. 10A employing a dual-core current transformer architecture. Accordingly, first image 1300 E depicts the CT sequentially stripped from the outermost layer towards the centre whilst second image 1300 F depicts a three dimensional quarter-cut sectional view with first to fifth tape layers 1330 A through 1330 E respectively and shielding 1360 . Accordingly, as shown the CT comprises a first core comprising first to fourth core elements 1310 A to 1310 D respectively surround a second core 1320 . Second core 1320 then has first tape layer 1330 A separating the first winding 1340 from it which is then overwound with second tape layer 1330 B. The first core (first to fourth core elements 1310 A to 1310 D) and second core 1320 respectively with their respective surrounding layers are then overwound with third tape layer 1330 C. Atop third tape layer 1330 C second winding 1350 is wound around first core (first to fourth core elements 1310 A to 1310 D) and second core 1320 . Second winding 1350 is then overwound by fourth tape layer 1330 D, shielding 1360 , fifth tape layer 1330 E and third winding 1370 . As depicted first winding 1340 corresponds to second secondary winding N 2 of FIG. 10 , second winding 1350 corresponds to first secondary winding N 1 of FIG. 10 , and third winding 1370 corresponds to the primary winding N 0 of FIG. 10 . Optionally a second shielding may be disposed between the first and second windings 1340 and 1350 respectively such as between second and third tape layers 1330 B and 1330 C respectively.
Second image 1300 F depicts a three dimensional quarter-cut sectional view with first to fifth tape layers 1330 A through 1330 E respectively and shielding 1360 removed thereby showing how the first to third windings 1340 , 1350 and 1370 respectively are wound around the closed magnetic elements forming the first, second, and third cores 1310 A, 1320 , and 1310 B respectively. It would be evident to one skilled in the art that the number of windings for each of the first to third windings 1340 , 1350 , and 1370 respectively and geometries of the first core (first to fourth core elements 1310 A to 1310 D) and second core 1320 respectively may be adjusted according to the electrical voltage, current and power of the signal being measured and design of the Asynchronous Power Measurement System within which the Current Transducer forms part. Further, a Hall sensor 1390 as described supra in respect of FIGS. 6A through 6C and FIGS. 11A through 11C is disposed within the second core 1320 in order to provide the determination and/or management of a DC field within the Current Transducer.
Also depicted in FIG. 13 disposed upon third first core element 1310 C is a magneto-strictive film 1380 which adjusts a dimension in respect to a magnetic field. Accordingly, the magneto-strictive film 1380 will increase/decrease in length along the axis of third first core element 1310 C when orientated appropriately such that the DC resistance of a thin-film upon the surface of the third first core element 1310 C or the third first core element 1310 C itself varies with the DC field within the third first core element 1310 C. Optionally, magneto-strictive elements may be disposed upon each of the first to fourth first core elements 1310 A through 1310 D respectively, and second core 1320 respectively and coupled to a Processing Circuit for processing in order to define an action, such as an alarm or provisioning of a compensation signal such as described above in respect of FIGS. 11A through 11C for example. Optionally, the magneto-strictive element 1380 may be employed in conjunction with a Hall sensor disposed within the second core 1320 . Optionally, multiple Hall sensors 1390 and magneto-strictive elements 1380 may be employed in conjunction with one another within/upon one or more magnetic cores of a Current Transformer.
Accordingly, it would be evident that Current Transducers as depicted in respect of FIGS. 11 through 13 may be amended to incorporate either a tertiary winding N 3 in isolation or a tertiary winding N 3 and quaternary winding N 4 such as described supra in respect of FIGS. 10A through 10C for example. Such a configuration is depicted in FIG. 14 by electrical circuit 1400 of a multi-core current transformer according to an embodiment of the invention. As depicted a CT R 1050 C, as described supra in respect of FIG. 10C , is augmented with first and second fluxgate coils 1430 A and 1430 B respectively. As depicted each of the first and second fluxgate coils 1430 A and 1430 B respectively are coupled to fluxgate driver 1420 which provides square wave and inverted square wave signals and the output signals from the first and second fluxgate coils 1430 A and 1430 B respectively are coupled to a summation circuit and demodulator (DEMOD) 1410 . Each of the DEMOD 1410 and driver 1420 are coupled to Processing Circuit 1440 . As depicted first and second fluxgate coils 1430 A and 1430 B respectively are excited with equal currents but in opposite directions thereby cancelling the overall effect upon the core of CT R 1050 C. Processing circuit 1440 may provide processing of the DEMOD 1410 in hardware and/or software or a combination thereof. For example, according to an embodiment of the invention processing circuit 1440 provides a square wave signal which comprises only odd harmonics such that effect of any magnetic field within the associated core of CT R 1050 C is to generate distorted output signals with even order harmonics which are filtered from the output of DEMOD 1410 by a second order low pass filter prior to being amplified and coupled to an integrator which also receives the output from the dual-stage current transformer within CT R 1050 C.
Within FIGS. 10C and 14 there are depicted Correction Winding 1 1070 and Correction Winding 2 1060 in conjunction with the first and second secondary windings respectively and their associated cores within the transformer. It would be evident to one skilled in the art that only one or other of the Correction Winding 1 1070 and Correction Winding 2 1060 may be employed.
FIG. 15 depicts a two stage current transformer in first and second images 1500 A and 1500 B respectively according to an embodiment of the invention utilizing a third core for the DC bias detection core which when resistively connected as described in FIG. 14 provides an implementation of a two stage Current Transducer with DC flux detection. Accordingly, the majority of the structures depicted in first and second images 1500 A and 1500 B respectively are common to the descriptions supra in respect of first and second images 1200 C and 1200 D in FIG. 12 reflecting the third circuit 1000 C in FIG. 10C . However, in addition to the elements in common with these first and second images 1200 C and 1200 D the first and second images 1500 A and 1500 B also depict first and second fluxgate coils 1430 A and 1430 B respectively together with Compensation Coil 1 1020 . As depicted is second image 1500 B the Compensation Coil 1020 is disposed around first core 1510 , second core 1220 , and third core 1210 B as is primary winding, third winding 1270 . Hall sensor 1280 is depicted disposed within third core 1210 B. Accordingly, in first image 1500 A the Compensation Coil 1020 is now formed upon the fifth tape layer 1230 E upon which is wound second Shield 1530 , sixth tape layer 1540 , and third winding 1270 .
Now referring to FIG. 16 there is depicted a current comparator in first and second images 1600 A and 1600 B respectively according to the embodiment of the invention, utilizing first and second fluxgate coils 1620 A and 1620 E respectively to detect input and output current—turn balance wherein there is no magnetic shield between the magnetic sensor and the primary and secondary windings in contrast to prior art toroidal transformers. Accordingly, as depicted in second image 1600 B the primary coil 1630 , with turns N 1 , and secondary coil 1640 , with turns N 0 , are wound around a single core 1610 together with first and second fluxgate sensors 1620 A and 1620 B respectively. As depicted in first image 1600 A the primary winding 1630 , secondary winding 1640 , and first and second fluxgate sensors 1620 A and 1620 B are wound around the single core 1610 with first tape layer 1650 A. Surrounding all of these are second tape layer 1650 B and shield 1660 . The inventors have established that other magnetic shield(s) can be removed where the toroidal transformer establishes the magnetic flux from the primary winding 1630 primarily through the magnetic core 1610 which is achieved through precision control of the windings in conjunction with a high quality magnetic core and low loading from the secondary winding 1640 . Alternatively, the magnetic core if the current comparator depicted within first and second images 1600 A and 1600 B of FIG. 16 may be a dual-core or multi-core design.
Within an embodiment of the invention operation of the current comparator depicted in FIG. 16 exploits the magnetic core 1610 as part of a magnetic field sensing apparatus continuously magnetized back and forth from saturation in one direction to saturation in the other direction wherein the time required to drive the magnetic core from saturation to saturation is used as a measure of the magnetic field strength. Within another embodiment of the invention two magnetic cores are employed in conjunction with a push-pull drive circuit for driving them from saturation to saturation thereby producing a differential output signal which beneficially reduces the coupling effects of the higher power magnetic drive circuit on the lower level output signal.
Referring to FIGS. 17A and 17B there are depicted current comparators according to an embodiment of the invention utilizing a Hall Effect magnetic sensor 1710 embedded within the magnetic core 1720 of the current comparator to detect input and output current—turn balance wherein the prior art magnetic shield between the magnetic sensor and the primary and secondary windings has been removed. As depicted in the cross-section of the current comparator comprises the Hall Effect magnetic sensor 1710 “around” which are wound the primary coil 1630 and secondary coil 1640 with the assembly then surrounded by magnetic shield 1730 which shields the current comparator from external magnetic fields. Optionally, a magnetic circuit may be employed in conjunction with the configuration depicted in FIG. 17A in order to concentrate magnetic field on the Hall effect magnetic sensor 1710 depending upon the geometry of the Hall effect magnetic sensor 1710 and the primary and second coils 1630 and 1640 respectively. However, adding such a magnetic element introduces hysteresis and impacts accuracy.
In contrast in FIG. 17B the primary coil 1630 is formed below the Hall Effect magnetic sensor 1710 and the secondary coil 1640 is formed above it. In this manner the primary and secondary coils 1630 and 1640 respectively may be manufactured and characterized independent from the overall transformer. Optionally, as with FIG. 17A magnetic field concentrator(s) may be employed to concentrate the magnetic field on the Hall effect magnetic sensor 1710 .
The current comparator depicted in FIG. 16 represents a design wherein the primary and secondary coil windings are implemented directly on the magnetic core. In contrast the current comparator depicted in FIGS. 17A and 17B exploits a magnetic sensor (Hall Effect) and may be implemented as a “planar” design although it may also be made as a toroid and may employ a number of Hall Effect (or other) sensors, or a single sensor with the magnetic field concentrator, for example a magnetic core with a cut slot.
Referring to FIG. 18 there is depicted an active current to current transducer (AC-CT) 1800 according to the embodiment of the invention utilizing current comparator with a magnetic sensor 1810 within magnetic core 1870 and an amplification block 1820 to produce AC and DC output current in precise ratio to the input current. Accordingly, an input current I I within a primary coil 1850 induces a magnetic flux within the magnetic core 1870 which is detected by magnetic sensor 1810 . The output of the magnetic sensor 1810 is amplified by amplification block 1820 and coupled to the secondary coil 1840 . Accordingly, the operation of the AC-CT 1800 may be viewed as an AC amplifier with transformer feedback although the operation is significantly different in that within the AC-CT 1800 the aim, rather than compensate the input voltage with the transformed output voltage, is to compensate a first magnetic flux generated by the current flowing within the input winding with a magnetic flux generated in the output winding, such that the overall induced magnetic flux as measured by the magnetic sensor 1810 is approximately equal to zero. It would be evident to one skilled in the art that this scheme is good for both AC current transduction as well as DC transduction. The concept of the AC-CT 1800 is similar to that employed within DC comparator resistance bridges. The physical implementations of AC-CT 1800 , in common with the current transducers depicted in FIGS. 16 and 17 , are absent magnetic shield(s) except external to the overall assembly in order to protect the current transducers from external magnetic fields only. However, such external magnetic shields are not essential from the conceptual viewpoint although they will be beneficial in reducing external electromagnetic interference fields do lower the “noise” level of the implementations.
Alternatively, with respect to embodiments of the invention, the transformer may be shell form or a combination of core and shell forms. Shell form designs may be more prevalent than core form designs for distribution transformer applications due to the relative ease in stacking the core around the winding coils. Core form designs tend to, as a general rule, be more economical, and therefore more prevalent, than shell form designs for high voltage power transformer applications at the lower end of their voltage and power rating ranges. At higher voltage and power ratings, shell form transformers tend to be more prevalent. Shell form design tends to be preferred for extra high voltage and higher MVA applications because, though more labor intensive to manufacture, shell form transformers are characterized as having inherently better kVA-to-weight ratio, better short-circuit strength characteristics and higher immunity to transit damage. However, it would be evident that embodiments of the invention may be applied to core form, shell form, and combination core-shell form transformers.
Within the descriptions presented supra in respect of FIGS. 10A through 14 the determination of corrections and alarms has been presented based upon determinations of DC magnetic fields arising from DC currents in respect to measurements of AC currents. In respect of corrections these are described primarily as being applied through the generation of opposing magnetic fields within the Current Transducer or the triggering of an alarm in respect of terminating a measurement, providing a warning, or truncating the measurements to a predetermined accuracy for example. However, as depicted in FIGS. 1 and 2 there is a surface or plurality of surfaces relating the error in an AC current measurement to the DC current and the AC current. Accordingly, within another embodiment of the invention the Processing Circuit depicted within FIGS. 11A through 11C may digitize the measured AC current and apply one or more corrections based upon one or more corrective algorithms to the digitized AC current based upon characterisation of these one or more surfaces. Such algorithms may be common to all measurement systems exploiting common coefficients or may be common algorithms exploiting coefficients derived from a characterisation of the Current Transducer wherein the derived coefficients are stored within a memory associated with the Processing Circuit.
Specific details are given in the above description to provide a thorough understanding of the embodiments. However, it is understood that the embodiments may be practiced without these specific details. For example, circuits may be shown in block diagrams in order not to obscure the embodiments in unnecessary detail. In other instances, well-known circuits, processes, algorithms, structures, and techniques may be shown without unnecessary detail in order to avoid obscuring the embodiments.
Implementation of the techniques, blocks, steps and means described above may be done in various ways. For example, these techniques, blocks, steps and means may be implemented in hardware, software, or a combination thereof. For a hardware implementation, the processing units may be implemented within one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, micro-controllers, microprocessors, other electronic units designed to perform the functions described above and/or a combination thereof.
The foregoing disclosure of the exemplary embodiments of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many variations and modifications of the embodiments described herein will be apparent to one of ordinary skill in the art in light of the above disclosure. The scope of the invention is to be defined only by the claims appended hereto, and by their equivalents.
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Accurate measurements of electrical power at various points of a power grid is becoming more important and, at the same time, is getting more difficult as the old power distribution model of a few, large power generating stations and a multitude of relatively linear loads is replaced by a newer model containing a multitude of smaller, and to some degree unpredictable power sources, as well as a multitude of not always linear and often smart (essentially also unpredictable) loads. Embodiments of the invention provide for management of AC current measurements in the presence of a DC current. Such current measurement management including at least alarms, feedback, and forward correction techniques exploiting magnetic field measurements from within the magnetic core or upon the surface of magnetic elements and/or shields within the current transducer.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is related to and claims priority from U.S. Provisional Patent Application No. 61/542,666, filed Oct. 3, 2011 and is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention generally relates to valves. More specifically, the present invention relates to flushometers or faucet valves having a flow noise restrictor.
BACKGROUND OF THE INVENTION
[0003] Numerous valves utilize a valve seat in their structure. Many of these structures have a valve structure that, typically, descends to seat upon the valve seat. Where there is a pressure differential between the area “upstream” of the valve seat and the area “downstream” of the valve seat, the energy of the system may be dissipated in undesirable ways. For example, cavitations and/or vibrations can occur, particularly at the moment the valve closes. These occurrences are often reflected in noise at the valve or its associated fixture or upstream/downstream due to vibrations traveling throughout the system. In liquid systems, the vibrations are sometimes caused by pressure waves traveling in the piping system that supplies the valve including what is commonly called water hammer. At other times the cause of the vibrations is more local due to gas trapped in the liquid providing an unstable dynamic system that tends to vibrate at certain flow conditions.
[0004] One particular type of valve that can exhibit “noise” problems is a flushometer, commonly used with water closets and urinals. Two particular types of flushometers are well known: diaphragm flushometers and piston flushometers. Diaphragm-type flushometers are exemplified by the flush valve shown in U.S. Pat. No. 6,616,119, which is hereby incorporated herein by reference. Piston-type flushometers are also known, as exemplified by the flush valve shown in U.S. Pat. No. 4,261,545, which is hereby incorporated herein by reference.
[0005] A flushometer or faucet valve includes a body 10 with an inlet 12 and outlet 14 , a valve assembly 15 with a valve seat 26 , a valve member 17 movable in the body 10 toward or away from the valve seat 26 to control flow from the inlet 12 to the outlet 14 . The valve assembly 15 has a pressure chamber 50 acting on one side of the valve member 17 opposing the inlet pressure on the other side of the valve member 17 . A bypass 40 connects the chamber 50 with the water inlet side. Pressure in the chamber 50 maintains the piston 80 or diaphragm 18 seated to the valve seat 26 and the valve assembly 15 in the closed position. There is a relief valve 30 , which may be a mechanical relief valve stem 32 or a solenoid 99 ( FIG. 3A ) driven, that vents the chamber 50 to the outlet 14 side of the valve to permit the piston 80 or diaphragm 18 to move away from the valve seat 26 and open and control the water flow thru the valve. The piston 80 or diaphragm 18 may have a portion 89 / 48 to keep it concentric to the valve seat 26 and in axial alignment with the valve seat 26 . The valve typically has a refill head 47 or similar flow control device on the outlet side of the diaphragm 18 or piston 80 to confine the path of flow. Valves of this kind are taught in prior art for example in U.S. Pat. Nos. 5,881,993; 5,887,848; 5,213,305; 5,244,179; 6,182,689; 6,260,576; 5,332,192 5,967,182.
[0006] It is well known, that in certain environmental and flow conditions, flushometers, such as those discussed above, can start to vibrate and cause noticeable and sometimes undesirable noise. Valve noise in the above described type of valves can be generated thru various mechanisms. If the pressure in some areas falls below vapor pressure due to the Bernoulli Effect, cavitation can occur, which can cause violent oscillations and forces on the valve. Air may become trapped or present in the air chamber, such as due to a high level of gas dissolved in the water from the inlet. Air entrapped in the pressure chamber 50 can introduce a different impedance, due to the variance in compression of the mixed air/water fluid compared to only water, of the piston/diaphragm and pressure chamber 50 and therefore make the flow unsteady. In addition, the piping upstream or downstream of the valve can cause undesirable oscillations in the valve.
[0007] This noise can also be described as flutter or water hammer. Numerous attempts have been made to address such noise. Some valves as described in U.S. Pat. No. 4,248,270 employ a resilient flow control device that deflects or deforms under the inlet pressure, and therefore dynamically controls the flow rate. U.S. Pat. No. 6,616,119 employs a diaphragm that has a molded rubber skirt on the inlet side of the flush valve which deforms with pressure and controls the flow. The skirt attempts to dampen vibration with “friction” tabs. The disadvantage of the resilient member often is that the modulus of elasticity of such members rapidly changes with temperature. It therefore makes it difficult to control the flow rates consistently over different operating temperatures due to the tabs' (of the '119 patent) friction against the outer diameter of the barrel.
[0008] Another means to control noise is to introduce friction between the moving diaphragm or piston and the valve housing. For example, U.S. Pat. No. 5,865,420 diaphragm teaches a refill head 47 on the outlet side of the valve which introduces friction between the housing and the moving refill head, therefore damping vibrations. The aforementioned refill head 47 on the inlet side also touches the housing barrel to introduce friction.
[0009] Some valves, e.g. U.S. Pat. No. 4,040,440 employ sound absorbing treatment on the outlet side, or generate turbulence as taught in U.S. Pat. No. 4,967,998. Some flushometer designs have grooves in the outlet skirt as well (made of plastic or metal) to control the flow as well. Other cage type valves employ perforated and grooved members, plugs and skirts as a means to make the flow turbulent to reduce noise throughout the flush cycle as shown in U.S. Pat. Nos. 4,024,891 or 3,990,475. However, the limited stroke of the chamber controlled valves does not allow for elaborate absorption treatment or perforation of members. In addition, the difficulty of those perforated and grooved members shown in prior art, is that even though they suppress noise thru the introduction of turbulence, they severely restrict flow thru the valve when the valve is in an open position or opening/closing stroke. In other configurations, the geometry adds friction or flow resistance to the opening or closing stroke. This cannot be adopted in valves that have a smaller stroke and larger flow rate requirements.
[0010] Further complicating matters, some of the portion of the noise/hammer occurs at the moment before the closing of the valve is completed. The Bernoulli effect is especially strong at that moment, as the inlet pressure builds up to static pressure of a typical residential or commercial water supply line, while at the same time the pressure on the outlet dramatically reduces (typical to atmospheric pressure). Present mechanisms at the outlet side of the valve seat have only little effect at that moment.
SUMMARY OF THE INVENTION
[0011] One embodiment of the invention relates to a flow noise restrictor having features for generating vortices.
[0012] One embodiment of the invention relates to a flush valve having a valve body having an inlet and an outlet. A valve assembly is included comprising a valve member and a valve seat. The valve member is seatable upon the valve seat to seal the inlet from the outlet. The valve assembly has a flow noise restrictor adjacent to the valve seat and partially defining a fluid flow path. The flow noise restrictor has a sidewall and a fluid flow edge defining a plurality of features.
[0013] One embodiment of the invention relates to a valve assembly comprising a valve member and a valve seat. The valve member is seatable upon the valve seat to seal the inlet from the outlet. The valve assembly has a flow noise restrictor adjacent to the valve seat and partially defining a fluid flow path. The flow noise restrictor has a sidewall and a fluid flow surface defining a plurality of features.
[0014] One embodiment of the invention relates to a flow noise restrictor for use with a valve assembly. The flow noise restrictor comprises a circular sidewall. The circular sidewall has an upper edge and a lower edge nonparallel with each other. One of the upper edge and lower edge configured to engage a portion of a flush valve. The other of the upper edge and lower edge define a plurality of features.
[0015] Additional features, advantages, and embodiments of the present disclosure may be set forth from consideration of the following detailed description, drawings, and claims. Moreover, it is to be understood that both the foregoing summary of the present disclosure and the following detailed description are exemplary and intended to provide further explanation without further limiting the scope of the present disclosure claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The foregoing and other objects, aspects, features, and advantages of the disclosure will become more apparent and better understood by referring to the following description taken in conjunction with the accompanying drawings, in which:
[0017] FIG. 1 is a side, partial sectional, view of a diaphragm flushometer.
[0018] FIG. 2 is a side, partial sectional, view of a piston flushometer.
[0019] FIG. 3A is a side, cross-sectional view of a diaphragm valve of one embodiment of the invention; FIG. 3B is a perspective, cross-sectional view of the diaphragm valve of FIG. 3A .
[0020] FIGS. 4A-4D illustrate diaphragm valve assemblies of various embodiments; FIG. 4A illustrates a flow noise restrictor having triangular features; FIG. 4B illustrates a flow noise restrictor having sinusoidal features; FIG. 4C illustrates a flow noise restrictor having irregular, sharp features; FIG. 4D illustrates a flow noise restrictor irregular, sharp features and large window openings.
[0021] FIG. 5A is a side, cross-sectional view of a piston valve of one embodiment of the invention; FIG. 5B is a perspective, cross-sectional view of the piston valve of FIG. 3A .
[0022] FIGS. 6A-6D illustrate piston valve assemblies of various embodiments; FIG. 6A illustrates a flow noise restrictor having piston features; FIG. 6B illustrates a flow noise restrictor having sinusoidal features; FIG. 6C illustrates a flow noise restrictor having irregular, sharp features; FIG. 6D illustrates a flow noise restrictor irregular, sharp features and large window openings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented here. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and made part of this disclosure.
[0024] In some embodiments, the present invention relates to a flow noise restrictor 100 associated with a valve assembly 15 in a flushometer valve 1 . The flow noise restrictor 100 may have features 110 (such as regular triangular features 111 , sinusoidal features 113 , and irregular triangular features 113 ), which create vortices between the valve member 17 and the valve seat 26 as the valve member 17 is being seated. The flow noise restrictor 100 narrows the inflow area as the valve assembly 15 closes. It should be appreciated that the water may flow through an area defined by the valve seat 26 and the flow noise restrictor 100 , with the features 110 of the flow noise restrictor 100 contributing to that area. As the distance between the flow noise restrictor 100 and valve seat 26 decreases during the valve assembly 15 closure, the percentage of the flow area contributed by the features 110 of the flow noise restrictor 100 increases. The features 110 of the flow noise restrictor 100 introduce larger scaled vortices that provide mixing of the fluid without significantly changing flow resistance in the open position or adding friction to the opening and closing stroke.
[0025] FIG. 1 illustrates a typical prior art diaphragm flushometer valve and FIG. 2 illustrates a typical prior art piston flushometer valve. The flush valve 1 includes a body 10 having an inlet 12 and an outlet 14 and a main valve seat 26 for sealing by a valve assembly 15 . A pressure chamber 50 , or electronic control mechanism (for example, as shown in FIG. 3A ), is typically provided above the valve assembly 15 . This pressure chamber 50 may be pressurized by the line pressure of the inlet through bypasses 40 which place the pressure chamber 50 in fluid communication with the inlet 12 . The pressure chamber 50 is sealed from the outlet 14 by a relief valve 30 of the valve assembly 15 . The relief valve 30 includes a relief valve stem 32 extending downward through a relief valve seat 38 within the valve assembly 15 such that unseating of the relief valve 30 , such as by tilting the valve stem 32 , allows venting of the pressure chamber 50 to the outlet 14 . This reduces the pressure in the pressure chamber 50 , allowing the valve assembly 15 to be forced off of the main valve seat 26 by the pressure of the inlet 12 . The water from the inlet 12 may then pass through the main valve seat 26 to the outlet 14 . The valve assembly 15 reseats as the pressure chamber 50 reaches equilibrium pressure with the inlet forces acting on the valve assembly 15 .
[0026] With reference to FIG. 1 (diaphragm flushometer) and FIG. 2 (piston flushometer), the valve assembly 15 is actuated by an operating handle 22 which is fastened to the valve body 10 by means of a coupling nut 23 . The handle 22 is connected to a plunger 27 which extends to the interior portion of the valve body 10 below the main valve seat 26 . As best shown in FIG. 2 , the plunger 27 is guided and supported by a bushing 28 and is restored by a spring 25 . A seal packing 33 may be snapped on the end of bushing 28 and prevents leakage outwardly from the handle opening. The valve 1 as shown in FIGS. 1 and 2 has a manual handle 22 for operation. The valve 1 is equally adaptable to automatic operation, for example by a solenoid 99 as set forth in U.S. Pat. No. 3,778,023, either by mechanized action on the handle 22 or an automatic actuation device directly interacting with the plunger 27 or relief valve stem 32 .
[0027] With respect to FIG. 1 , the valve assembly 15 of a diaphragm flushometer valve is a diaphragm assembly 16 that includes a diaphragm 18 . In one embodiment, the diaphragm 18 is peripherally held to the body 10 by an inner cover 20 . The diaphragm 18 is seated upon a shoulder 21 at the upper end of body 10 and is clamped in this position by the inner cover 20 . An outer cover 24 is screw threaded onto the body 10 to hold the inner cover 20 in position.
[0028] The diaphragm assembly 16 , as shown in the embodiment of FIG. 1 , is closed upon a valve seat 26 formed at the upper end of a barrel 31 . The barrel 31 forms the conduit connecting the valve seat with outlet 14 . The diaphragm assembly 16 includes a relief valve 30 having a downwardly extending stem 32 carrying a movable sleeve 34 . Sleeve 34 is positioned for contact by a plunger 27 when operated by a handle 22 as its is conventional in the operation of flush valves 1 of the type described.
[0029] In one embodiment, the diaphragm assembly 16 , in addition to diaphragm 18 and the relief valve 30 , includes a retaining disk 19 , a refill ring 45 and a flow control ring 44 . It should be appreciated that the diaphragm 18 may be a unitary component, such as described in U.S. Pat. No. 7,980,528, incorporated by reference herein. The underside of the retaining disk 19 is threadedly attached to a collar 46 , which in turn is threadedly attached at its exterior to a sleeve 48 which carries the refill ring 45 . The above described assembly of elements firmly holds the diaphragm 18 between the upper face of the refill ring 45 and a lower facing surface of the collar 46 .
[0030] Above the diaphragm assembly 16 is the pressure chamber 50 , which maintains the diaphragm assembly 16 in a closed position when the flush valve 1 is not in use. The pressure chamber 50 is fillable via the bypasses 40 and vents through the relief valve 30 into the barrel 31 and ultimately the outlet 14 of the flush valve 1 .
[0031] As is known in the art, such as FIG. 1 , when the handle 22 is operated, the plunger 27 will contact sleeve 34 , lifting the relief valve 30 off its seat on the retaining disk 19 . This will permit the 50 discharge of water within the pressure chamber 50 down through the sleeve 84 . Inlet pressure will then cause the diaphragm 18 to move upwardly off its seat 26 , permitting direct communication between the inlet 12 and the outlet 14 through the space between the bottom of the diaphragm assembly 16 and the seat 26 . As soon as this operation has taken place, the pressure chamber 50 will begin to build through the bypass orifice 40 in the diaphragm assembly 16 . As flow continues into the pressure chamber 50 , the diaphragm assembly 16 will move toward its valve seat 26 and stop when it has reached that position, the flush valve 1 will be closed.
[0032] The diaphragm 18 of FIG. 1 has a peripheral edge 52 which will be held between the shoulder 21 of the body 10 and the inner cover 20 . Spaced from the edge 52 is a downwardly extending rim 35 , shown particularly in the section of FIG. 1 . When in the closed position, the rim 35 will extend about the upper end of the barrel 31 . In one embodiment, the features 110 are sized on a order of magnitude relative to the distance of the stroke of the valve assembly 15 .
[0033] Generally speaking, for a manual valve, the valve 1 is opened when an relief valve stem 32 is moved and opens a passage to the pressure chamber 50 above the diaphragm 18 or piston 80 , and vents at least a portion the liquid to the outlet 14 side of the valve 2 , therefore lowering the pressure above the diaphragm 18 or piston 80 and allowing the pressure below the diaphragm 18 or piston 80 to move the respective diaphragm 18 or piston 80 , thus opening the valve. For embodiments using an automatic actuation mechanism that triggers the plunger 27 , a similar process occurs. For embodiments utilizing a separate actuation mechanism from the traditional handle 22 , such as utilizing a solenoid, the pressure chamber 50 above the diaphragm 18 /piston 80 is opened by electronic means such as a latching solenoid valve 99 , draining said cavity to the outlet side of the valve 1 , allowing the piston 80 /diaphragm 18 to move to the open position. Various automatic or manual actuation systems are known in the art and may be used without departing from embodiments of the present invention.
[0034] In one embodiment, the flow noise restrictor 100 may be used with a piston flushometer having piston assembly 79 . A piston assembly 79 indicated generally at 34 is adapted to reciprocate within the body 10 . Although one embodiment of a piston assembly 79 is described below, it should be appreciated that the various types of piston assemblies may be used without departing from the present invention. The piston assembly 79 includes a hollow, generally cylindrical piston 80 . The piston 80 has a lower cylindrical portion 89 which is directly adjacent a piston seat area 73 , with the seat area 73 being normally seated upon a seal 83 to close the main valve seat 26 and to thereby control the flow of water through the flushometer valve 1 .
[0035] The piston 80 of FIG. 2 has a pair of bypass orifices 40 , which are illustrated with an optional filter ring 43 , which ring 43 functions according to known principles for providing additional anti-clogging properties. The interior chamber 42 of the piston 80 has an relief valve seat 38 , which may include a seal 83 . The seat 38 and seal 83 are at the top of a central passage which connects chamber 42 with the outlet 14 side of the flushometer valve 1 .
[0036] The piston assembly 79 also includes a relief valve 30 which normally closes the piston 80 . The relief valve 30 has a shoulder 49 which engages the seal 83 . An operating stem 32 is slidable in the interior chamber 42 of the relief valve 30 and extends to a point adjacent plunger 27 . A spring 85 assists in holding the relief valve 30 in its position to close and seal chamber 42 .
[0037] The piston assembly 79 further includes a cap 86 threadedly engaging the upper wall of piston 80 . The cap 86 has a central stop 87 against which the spring 85 abuts. The stop has holes 88 which provide fluid communication between the piston interior chamber 42 and an upper pressure chamber 50 . A packing member or seal member 64 held between the cap 86 and piston 80 provides a slidable seal separating the pressure chamber 50 from the inlet's 12 water pressure except through the bypass 43 .
[0038] The piston 80 has a cylindrical wall 70 which is preferably smooth and unobstructed. Directly adjacent the cylindrical wall 70 is a tapered piston area 72 which may have a taper of on the order of about ten degrees, which taper is effective to provide a clear flow path about the piston when it is in the raised position away from the valve seat 26 . Directly adjacent the tapered area 72 is the piston seat area 73 which will close upon the seat 26 when the valve is in the closed position. Directly downstream of the piston seat area 73 is a ring 74 which has an outer diameter slightly less than the diameter of the valve outlet adjacent the seat 26 so that ring area 74 will be inside of the valve seat 26 when the piston 80 is closed. The ring 74 functions as a throttling means in that it substantially reduces flow through the valve outlet just prior to complete valve closure.
[0039] Directly adjacent the throttling ring 74 is cylindrical portion 89 which has a plurality of radially and axially extending ribs 76 . The outer diameter of the ribs 76 is less than wall 70 and just slightly less than the passage through seat 26 . The ribs 76 are thus inside of the major portion of the piston 80 so as not to restrict flow. In a preferred embodiment five ribs 76 are provided for maximizing stability and guidance for the piston 80 , without detrimentally obstructing water flow past the piston 80 when the piston 80 is in the valve open position. At the lower end of each of the axially extending ribs there is a chamfered area 78 which assists in assembling the piston 80 within the flushometer valve 1 .
[0040] The area between each of the circumferentially, generally uniformly spaced ribs 76 is closed by a skirt 90 . As shown, the skirt 90 has a radius slightly less than the exterior surface of the ribs 76 . The function of the skirt 90 is to close the area between ribs to provide control of water flow past the piston 80 , which in turn will provide a more consistent operation of the flushometer. The skirt 90 improves the flow path by maintaining it in an axial direction generally circumferentially about the cylindrical piston portion 89 . By preventing water flow into the sleeve 48 , the skirt 90 also helps prevent any back pressure which might retard closure of the relief valve 30 .
[0041] Typically, during the flush cycle, the water below the valve assembly 15 and passing over the main valve seat 26 exhibits generally laminar flow. The present invention relates to the suppression of noise in valve assemblies. In one embodiment, the present invention suppresses noise at the closing of the valve by causing a maximized pressure drop right before valve closure and also introducing vortices (whirling flow +turbulent flow) into the flow to stabilize the flow across the valve seat 26 . Whirling flow suppresses noise while at the same time not restricting the flow.
[0042] In one embodiment, the invention may be in a form of a flow noise restrictor 100 at the inlet side of the valve. The flow noise restrictor 100 may be a portion of the rim 35 , with a series of regular or irregular features 100 . In some embodiments, the flow noise restrictor 100 is near to the valve seat 26 , such as adjacent the valve seat 26 . FIGS. 3A-4D illustrate a diaphragm assembly 16 flushometer valve 1 having a flow noise restrictor 100 of the present invention. FIGS. 5A to 6D illustrate a solenoid controlled piston assembly 78 flushometer valve 1 having a flow noise restrictor 100 of the present invention.
[0043] In some embodiments the flow noise restrictor 100 includes a sidewall 101 , a valve assembly surface 102 adjacent a portion of the valve assembly, for example abutting against the diaphragm 18 , and a flow surface 103 , which may be an edge or face of the sidewall 101 . In one embodiment, the flow noise restrictor 100 has a ring-like shape. The flow surface 103 is defined by a plurality of features in the sidewall 101 . In one embodiment, the flow surface 103 is non-parallel with the valve assembly surface 102 and/or the valve member 17 .
[0044] It is not necessary, in one embodiment, for the flow noise restrictor 100 to be in direct contact with the valve seat 26 or the valve body 10 . The flow noise restrictor 100 controls the flow through the valve 1 by restricting the area through which the flow may pass. In one embodiment, more as the piston 80 or diaphragm 18 reaches the valve seat 26 and less as the valve fully opens. In certain embodiments, the flow noise restrictor 100 has proportions relative to the other components of the flushometer valve 1 and particularly relative to the area through which the water flows during a flush cycle that allow for the impact of the induced vortices to become meaningful just prior to the valve 1 closing. It should be appreciated that such allows for unhindered flow when the valve 1 fully opens, but creates an increasing pressure drop before flow reaches the valve seat 26 while closing. This is achieved by giving the flow noise restrictor 100 a variable circumferential cross section, where the cross sectional area (allowing for water flow, such as the area of windows 58 ) increases in the direction of the opposing portion of the valve assembly 15 .
[0045] In one embodiment, the flow noise restrictor 100 comprises a series of features 110 , which may have one or more associated shape (such as triangular 111 , sinusoidal 112 , or irregular triangular 113 ). For embodiments as discussed where the cross sectional area increases, these features 110 have, on average, a decreasing width from a portion of the feature closest the valve assembly surface 102 of the flow noise restrictor 100 . It should be appreciated that individual features 110 may have an inverted shape where the width decreases but the overall total width of all features 110 increases. The features 110 may be such that the flow surface 103 defines a side of the sidewall 101 .
[0046] In one embodiment, at least a portion of the features 110 are holes in the flow noise restrictor 100 . For embodiments where the cross sectional area increases, the area of the holes and/or the number of holes may increase towards the flow surface 103 of the flow noise restrictor 100 . For each particular annular cross-sectional slice or plane, the features define a width. The width of the features may vary in each cross-sectional slice. For example, the width may increase as one proceeds from the valve assembly surface 102 to the flow surface 103 .
[0047] In one embodiment, the flow noise restrictor 100 includes a sidewall 101 that is either curved, curvilinear, or a series of linear edges. The height of the sidewall 101 , i.e. the distance between the flow surface 103 and the valve assembly 15 may vary. In one embodiment, the features 110 are symmetrical. In another embodiment, the features 110 are nonsymmetrical, i.e. irregular.
[0048] In one embodiment illustrated in FIG. 4A (diaphragm) and FIG. 6A (piston flushometer), this is achieved with triangular shaped features 111 in the sidewall 101 of the flow noise restrictor 100 , which is spaced about the circumference of the valve seat 26 . The triangular pattern around the circumference could be replaced with other geometries such as semi circular or sinusoidal 112 ( FIG. 4B (diaphragm) and FIG. 6B (piston flushometer)), as long as it has a large base area that gets gradually smaller away from flow surface 103 . In addition, the features 110 may be irregular such as FIG. 4C (diaphragm) and FIG. 6C (piston flushometer),
[0049] In one embodiment, there are at least three features 110 along the circumference of the valve seat. In one embodiment, as many features 110 as feasible are provided to introduce multiple three-dimensional vortical flow structures into the inlet flow to the valve seat 26 , with the hi and low differential in the geometry of the flow noise restrictor 100 . However, the circumferential structures/features need to stay large enough to influence the flow gradually over a larger part of the closing stroke of the diaphragm 18 /piston 80 . In addition, in one embodiment, the features 110 of the flow noise restrictor 100 may be sharp features to add small scale turbulent structures to the inflow of the valve seat 26 geometry. In one embodiment, the features 110 are substantially evenly spaced annularly about the flow noise restrictor 100 .
[0050] In the preferred embodiment the flow noise restrictor 100 on the inlet side of the valve seat 26 is combined with an existing noise reduction design such as methods of friction and flow restriction. This allows for two steps of pressure reduction between the inlet 12 and outlet 14 of the closing valve 1 and therefore minimizes the possibility of cavitation noise. First, the flow noise restrictor 100 provides for a pressure reduction. Second, the refill ring 45 (e.g, for a diaphragm flushometer) provides a reduction in pressure on the outlet 14 side. The use of the flow noise restrictor 100 allows for the suppression of noise (vibration) purely by manipulating the flow.
[0051] In one embodiment, the flow noise restrictor 100 is positioned adjacent either the valve seat 26 or the piston 80 /diaphragm 18 . In an embodiment, the flow noise restrictor 100 is mounted on a moving member of the valve 1 , such as the diaphragm 18 or piston 78 , but an alternate method can be envisioned where the flow noise restrictor 100 can be part of the valve housing or made of two parts, one part being attached to the housing or valve seat and one attached to the diaphragm 18 /piston 80 . In one embodiment, a piston flushometer includes the flow noise restrictor positioned about the periphery of the piston 80 . In one embodiment, at the tapered area 72 . In a further embodiment, the flow noise restrictor 100 includes a portion about the periphery of the piston 80 and a corresponding portion engagable therewith on the valve seat 26 .
[0052] In one embodiment, the downwardly extending rim 35 comprises the flow noise restrictor 100 , with the features 110 being defined by portions of the rim 35 that are removed.
[0053] In one embodiment, the features may include one or more windows 58 . As shown in FIGS. 4D and 6D , wherein the flow noise restrictor 100 includes a plurality of windows 58 which will modulate the flow of water as the diaphragm 18 (or piston 80 ) closes upon the valve seat 26 at the upper end of the barrel 31 . The windows 58 provide a uniform shape that does not alter the flow area as the valve closes, i.e. the cross-sectional area remains the same during closing. The windows 58 are significant openings in the flow noise restrictor 100 sidewall 101 when compared to the size of the individual features 110 . The window's 58 geometry size and shape is not small enough to add sufficient vorticity to suppress noise.
[0054] In one embodiment, the features 110 are molded into the flow noise restrictor 100 . In another embodiment, the flow noise restrictor 100 is cut/drilled to form the features 110 .
[0055] In one embodiment, the flow noise restrictor 100 does not contact the barrel 31 or valve seat 26 .
[0056] The foregoing description of illustrative embodiments has been presented for purposes of illustration and of description. It is not intended to be exhaustive or limiting with respect to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the disclosed embodiments. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents.
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A flow noise restrictor for use with a valve. The flow noise restrictor reduces the flow area as the valve closes and forms vortices to reduce the noise such as due to the Bernoulli effect.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a variable displacement compressor which controls the inclined angle of a swash plate based on the difference between the pressure in the crank chamber and the suction pressure to control the discharge displacement. More specifically, this invention relates to a variable displacement compressor which can stop the circulation of the gas through the compressor and an external circuit when the inclined angle of the swash plate is minimum.
2. Description of the Related Art
In general, compressors are mounted in vehicles to supply compressed refrigerant gas to the vehicle's air conditioning system. To maintain the air temperature inside the vehicle at a level comfortable for the vehicle's passengers, it is important to use a compressor having a controllable displacement. One known compressor of this type controls the inclination of a swash plate, tiltably supported on a drive shaft, based on the difference between the pressure in a crank chamber and the suction pressure, and converts the rotational motion of the swash plate to reciprocal linear motion of each piston.
The compressor described above has no electromagnetic clutch for the transmission and blocking of power between an external driving source and the drive shaft of the compressor. The external driving source is coupled directly to the drive shaft. The clutchless structure with the driving source coupled directly to the drive shaft eliminates shocks that would otherwise be produced by the ON/OFF action of such a clutch. When such a compressor is mounted in a vehicle, passenger comfort is improved. The clutchless structure also reduces the overall weight of the cooling system and thus reduces costs.
In such a clutchless system, the compressor runs even when no cooling is needed. With such compressors, it is important that, when cooling is unnecessary, the discharge displacement be reduced as much as possible to prevent the evaporator from frosting. When no cooling is needed or there is a probability of frosting, the circulation of the refrigerant gas through the compressor and its external refrigeration circuit should be stopped. The compressor shown in FIG. 5 is designed to block the flow of gas into a suction chamber 54 from an external refrigeration circuit (not shown) by the use of a spool 50 to stop the circulation of the refrigerant gas.
As shown in FIG. 5, the cylindrical spool 50 is slidably accommodated in a shutter chamber 52 defined in a cylinder block 51. The spool 50 moves along the axis of a drive shaft 56, in accordance with the tilting of a swash plate (not shown) supported by the drive shaft 56. A rear end of the drive shaft 56 is inserted into the spool 50. A ball bearing 57 is positioned between the rear end of the drive shaft 56 and the inner circumferential surface of the spool 50. The rear end of the drive shaft 56 is supported by the ball bearing 57 and the spool 50 in the shutter chamber 52. The compressor has a suction passage 53 connected to the external refrigeration circuit. The suction passage 53 is communicated with the suction chamber 54 through the shutter chamber 52. A positioning surface 55 is defined in the cylinder block 51 between the shutter chamber 52 and the suction chamber 54.
When the swash plate is fully inclined and thus the compressor displacement is maximal, the spool 50 is moved to an open position as shown by the solid lines in FIG. 5, where the spool 50 enables communication between the suction passage 53 and the suction chamber 54. Therefore, the refrigerant gas flows into the suction chamber 54 from the external refrigeration circuit and circulates between the external refrigeration circuit and the compressor. As the swash plate becomes less inclined from this state, the spool 50 moves toward the positioning surface 55. When the inclination of the swash plate is minimal and thus the compressor displacement is minimal, the spool 50 abuts against the positioning surface 55 as shown by the double-dotted lines in FIG. 5. The abutment restricts the movement of the spool 50 toward the positioning surface 55 and positions the spool 50 at a closed position. The spool 50 disconnects the suction passage 53 from the suction chamber 54. Accordingly, the refrigerant gas stops flowing into the suction chamber 54 from the external refrigeration circuit, thereby preventing circulation of the refrigerant gas between the external refrigeration circuit and the compressor.
When moving between the open and closed positions, the spool 50 slides in the axial direction of the shutter chamber 52 with respect to the inner circumferential surface of the shutter chamber 52. In addition, although the rear end of the drive shaft 56 is supported by the ball bearing 57 in a manner such that it is relatively rotatable with respect to the spool 50, the spool 50 is also relatively rotatable with respect to the inner circumferential surface of the shutter chamber 52 in the circumferential direction. For this reason, rotation of the drive shaft 56 may cause the spool 50 to rotate with the shaft 56 and may result in the spool 50 sliding with respect to the inner circumferential surface of the shutter chamber 52 in the circumferential direction. Such sliding causes friction between the spool 50 and the inner circumferential surface of the shutter chamber 52 and prevents smooth movement of the spool 50. Furthermore, when the spool 50 moves to the closed position, the drive shaft 56 may rotate with the spool 50, which is abutted against the positioning surface 55. This may cause friction of the spool 50 and the positioning surface 55.
The refrigerant gas includes a mist-like lubricant. When the compressor is operated, the lubricant flows with the refrigerant gas inside the compressor and circulates in each section of the compressor. However, when the operation of the compressor is stopped, there are cases in which the refrigerant gas inside the compressor coheres and becomes liquefied. Liquefied refrigerant may also flow into the compressor from the external refrigeration circuit. When operation of the compressor is resumed in such a state, the lubricant inside the compressor is washed away by the liquefied refrigerant and is discharged to the external refrigeration circuit along with this liquefied refrigerant. As a result, the amount of lubricant in the compressor decreases. Thus, lubrication in the compressor becomes insufficient. Such insufficient lubrication, when operation of the compressor is resumed, leads to an increase in friction.
Friction heat produced by the rotation of the spool 50, while it is contacting the positioning surface 55, results in a microscopic deformation of the contact area between the spool 50 and the positioning surface 55. This decreases the effectiveness of the seal between the members 50 and 55. Dimensional manufacturing errors of parts such as the spool 50 and the positioning surface 55 may also decrease the seal effectiveness. A decrease in the seal effectiveness between the spool 50 and the positioning surface 55 results in gas flow between the suction passage 53 and the suction chamber 54. This permits some circulation of the refrigerant gas between the external refrigeration circuit and the compressor which may result in frosting.
SUMMARY OF THE INVENTION
Accordingly, it is a primary objective of the present invention to provide a variable displacement compressor which ensures the reducing of friction between parts contacting each other.
Another objective of the present invention is to provide a variable displacement compressor having a blocking member which can securely stops the circulation of refrigerant gas.
To achieve the above objects, the compressor according to the present invention has a housing body, a drive shaft, a swash plate, a piston and a cylinder. The swash plate converts rotation of the drive shaft to reciprocating movement of the piston in the cylinder bore. The piston compresses gas supplied to the cylinder bore from an external circuit via a suction chamber and discharges the compressed gas to a discharge chamber. The swash plate is tiltable with respect to a plane perpendicular to the axis of the drive shaft according to differential pressure between that in the crank chamber and that in the suction chamber. The swash plate controls displacement of the compressor based on the inclination thereof. A member is movable between a first position and a second position in response to the inclination of the swash plate. The member connects the external circuit with the suction chamber in the first position and disconnects the external circuit from the suction chamber in the second position. The housing body has a surface slidably engaged with the member. A coating layer is provided on at least one of the member and the slide surface to reduce the resistance occurring due to the sliding movement of the member on the slide surface.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention that are believed to be novel are set forth with particularity in the appended claims. The invention, together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:
FIG. 1 is a longitudinal cross-sectional view showing a compressor according to a first embodiment of the present invention;
FIG. 2 is an enlarged partial cross-sectional view showing the section encompassed by circle A in FIG. 1;
FIG. 3 is an enlarged partial cross-sectional view showing the section encompassed by circle B in FIG. 1;
FIG. 4 is an enlarged partial cross-sectional view of the compressor according to a second embodiment of the present invention; and
FIG. 5 is a partial cross-sectional view of a prior art compressor.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A compressor according to a first embodiment of the present invention will now be described with reference to FIGS. 1 through 3.
As shown in FIG. 1, a cylinder block 1 made of aluminum or aluminum alloy is provided. A front housing 2 is secured to the front end of the cylinder block 1. A rear housing 3 is secured to the rear end of the cylinder block 1 with a first plate 4, a second plate 43, a third plate 44 and a fourth plate 45 sandwiched between them. The cylinder block 1, the front housing 2 and the rear housing 3 constitute a housing body.
A crank chamber 5 is defined in the front housing 2. A drive shaft 6 is supported rotatably on the front housing 2 and the cylinder block 1. The front end of the drive shaft 6 protrudes outside the crank chamber 5 and is secured to a pulley 7. The pulley 7 is coupled to an engine of a vehicle (not shown) via a belt 8.
A swash plate 10 is supported by the drive shaft 6 in such a way as to be slidable along and tiltable with respect to the axis L of the shaft 6. A pair of guide pins 12 is secured to the swash plate 10. Guide balls 12a are formed at the distal ends of the respective guide pins 12. A rotary plate 9 is fixed to the drive shaft 6. The rotary plate 9 has a support arm 11 protruding toward the swash plate 10 (rearward) from the rotary plate 9. A pair of guide holes 11a are formed in the arm 11, and the guide balls 12a are slidably fitted in the associated guide holes 11a.
The cooperation of the arm 11 and the guide pins 12 permits the swash plate 10 to rotate together with the drive shaft 6 and to tilt with respect to the drive shaft 6. The tilting of the swash plate 10 is guided when the guide balls 12a slide in the associated guide holes 11a and the swash plate 10 slides along the axis L of the drive shaft 6.
A shutter chamber 13 is formed in the center portion of the cylinder block 1, extending along the axis L of the drive shaft 6. A hollow cylindrical spool 14 is accommodated in the shutter chamber 13 in such a way as to be slidable along the axis L of the drive shaft 6. The spool 14 is preferably made of aluminum or aluminum alloy. The spool 14 has a large diameter portion 14a and a small diameter portion 14b and a step between them. A coil spring 15 is located between the step on the spool 14 and the inner wall of the shutter chamber 13. The coil spring 15 urges the spool 14 toward the swash plate 10.
As shown in FIGS. 1 and 2, the rear end of the drive shaft 6 is inserted in the spool 14. An angular contact ball bearing 16 is located between the rear end of the drive shaft 6 and the inner wall of the large diameter portion 14a of the spool 14. The ball bearing 16 receives loads in the radial direction and the thrust direction that are applied to the drive shaft 6. The rear end of the drive shaft 6 is supported by the inner wall of the shutter chamber 13 through the ball bearing 16 and the spool 14. The ball bearing 16 has an outer race 16a fixed to the inner wall of the large diameter portion 14a and an inner race 16b, which is slidable along the axis L of the drive shaft 6. Therefore, the ball bearing 16 moves together with the spool 14 along the axis L of the drive shaft 6.
A step portion 6a is formed on the rear outer surface of the drive shaft 6. The engagement of the inner race 16b of the ball bearing 16 and this step portion 6a inhibits the movement of the ball bearing 16 toward the swash plate 10 (frontward). At the same time, the engagement prohibits the spool 14 from moving toward the swash plate 10.
As shown in FIG. 1, a suction passage 17 is formed in the center portion of the rear housing 3, extending along the axis L of the drive shaft 6. The suction passage 17 communicates with the shutter chamber 13. A positioning surface 18 is formed on the cylinder block 1 between the shutter chamber 13 and the suction passage 17. The rear end face of the spool 14 constitutes a shutter surface 19, which is adapted to abut against the positioning surface 18. As the shutter surface 19 abuts against the positioning surface 18, the movement of the spool 14 in a direction away from the swash plate 10, or in the rearward direction, is restricted and the suction passage 17 is disconnected from the shutter chamber 13.
A pipe 20 is slidably attached to the drive shaft 6 between the swash plate 10 and the ball bearing 16. The front end of the pipe 20 is engagable with the rear end face of the swash plate 10. The rear end of the pipe 20 contacts only the inner race 16b of the ball bearing 16.
As the swash plate 10 moves toward the spool 14, it pushes the pipe 20. The pipe 20 in turn pushes the inner race 16b of the ball bearing 16. As a result, the spool 14 moves toward the positioning surface 18 against the urging force of the spring 15, and the shutter surface 19 of the spool 14 abuts against the positioning surface 18. At this time, the inclination of the swash plate 10 is restricted to be minimized. The minimum inclination of the swash plate 10 corresponds to a position slightly deviated or inclined from a position perpendicular to the axis L.
When the inclination of the swash plate 10 reaches the minimum, the spool 14 comes to a closed position to disconnect the suction passage 17 from the shutter chamber 13. The spool 14 is movable between the closed position and an open position (see FIG. 1) spaced from the closed position, and is positioned in response to the movement of the swash plate 10. As shown in FIG. 1, as a projection 21 of the front face of the swash plate 10 abuts against the rotary plate 9, the swash plate 10 is restricted not to incline beyond a predetermined maximum inclination.
A plurality of cylinder bores 22 are formed in the cylinder block 1 to communicate with the crank chamber 5. Single-headed pistons 23 are retained in the associated cylinder bores 22. The hemispherical portions of a pair of shoes 24 are fitted on each piston 23 in a mutually slidable manner. The swash plate 10 is held between the flat portions of both shoes 24. Accordingly, the undulation of the swash plate 10 caused by the rotation of the drive shaft 6 is transmitted through the shoes 24 to each piston 23, so that each piston 23 reciprocates in the associated cylinder bore 22 in accordance with the inclination of the swash plate 10.
A suction chamber 25 and a discharge chamber 26 are defined in the rear housing 3. Suction ports 27 and discharge ports 29 are formed in the first plate 4. Suction valves 43a are formed on the second plate 43, and discharge valves 44a are formed on the third plate 44. As each piston 23 moves backward, or away from the suction chamber 25, the refrigerant gas in the suction chamber 25 forces the associated suction valve 43a to open and flows into the associated cylinder bore 22 through the associated suction port 27. As each piston 23 moves forward, or toward the discharge chamber 26, the refrigerant gas in the cylinder bores 22 forces the associated discharge valve 44a to open and flows into the discharge chamber 26 through the associated discharge port 29. As each discharge valve 44a abuts against a retainer 45a formed on the fourth plate 45, the degree of opening of the associated discharge valve 44a is restricted.
The suction chamber 25 communicates with the shutter chamber 13 via a communication hole 31. The communication hole 31 is blocked from the suction passage 17 when the shutter surface 19 of the spool 14 abuts against the positioning surface 18. The suction passage 17 forms an inlet to supply the refrigerant gas into the compressor. Therefore, the spool 14 blocks the passage of the refrigerant gas from the suction passage 17 to the suction chamber 25 downstream of that inlet.
A passage 32 is formed in the drive shaft 6. The passage 32 has an inlet 32a open to the crank chamber 5 in the vicinity of the front end of the drive shaft 6, and an outlet 32b open to the interior of the spool 14. A pressure release hole 33 is formed in the rear end face of the spool 14. The hole 33 communicates the interior of the spool 14 with the shutter chamber 13.
A supply passage 34 connects the discharge chamber 26 to the crank chamber 5. An electromagnetic valve 35 is attached to the rear housing 3 and is located midway in the supply passage 34. When the solenoid 28 of the electromagnetic valve 35 is excited, a valve body 30 closes a valve hole 35a. When the solenoid 28 is de-excited, the valve body 30 opens the valve hole 35a. Therefore, the electromagnetic valve 35 selectively opens or closes the supply passage 34 between the discharge chamber 26 and the crank chamber 5.
An external refrigeration circuit 37 connects the suction passage 17 for supplying the refrigerant gas into the suction chamber 25 to the outlet port 36 for discharging the refrigerant gas from the discharge chamber 26. Provided above the external refrigeration circuit 37 are a condenser 38, an expansion valve 39, and an evaporator 40. The expansion valve 39 controls the flow rate of the refrigerant in accordance with a change in gas pressure on the outlet side of the evaporator 40. A temperature sensor 46 is located near the evaporator 40. The temperature sensor 46 detects the temperature in the evaporator 40, and outputs a signal based on the detected temperature to a controller C.
The controller C controls the solenoid 28 of the electro-magnetic valve 35 based on the signal from the temperature sensor 46. When the temperature detected by the temperature sensor 46 is equal to or below a predetermined value while an activation switch 47 of the air conditioning system is set on, the controller C de-excites the solenoid 28 to prevent frosting from taking place in the evaporator 40. The controller C de-excites the solenoid 28 when the activation switch 47 is switched off.
As shown in FIG. 2, a fluororesin coating 41 is provided on the outer circumferential surface of the large diameter portion 14a of the spool 14. The fluororesin coating 41 is applied with the aid of blast painting or the like. In the present embodiment, ETFE (copolymer of ethylene and tetrafluoroethylene) is used for the coating 41. The thickness of the coating 41 is preferably 40-60 μm.
As shown in FIG. 3, a fluororesin coating 42 is provided on the shutter surface 19 of the spool 14. The fluororesin coating is applied with the aid of blast painting or the like. In the same manner as the coating 41, ETFE is used for the coating 42, and its preferred thickness is 40-60 μm. In FIGS. 2 and 3, the thickness of the coatings 41 and 42 is exaggerated.
The operation of the compressor will now be described.
FIG. 1 shows the solenoid 28 in an excited state in which the supply passage 34 is closed. Therefore, the refrigerant gas under high pressure in the discharge chamber 26 is not supplied to the crank chamber 5. In this situation, the refrigerant gas in the crank chamber 5 simply flows out to the suction chamber 25 via the passage 32 and the pressure release hole 33 so that the pressure in the crank chamber 5 approaches the low pressure in the suction chamber 25, i.e., the suction pressure. As a result, the pressure difference between the crank chamber 5 and the cylinder bores 22 is reduced and the inclination of the swash plate 10 becomes maximized. The discharge displacement of the compressor is thus maximized.
When the gas is discharged with the swash plate 10 kept at the maximum inclination while the cooling load of the compressor becomes lower, the temperature in the evaporator 40 falls to approach the value that may cause frosting. When the temperature detected by the temperature sensor 46 becomes equal to or lower than the predetermined value, the controller C de-excites the solenoid 28. When the solenoid 28 is de-excited, the supply passage 34 is opened to connect the discharge chamber 26 to the crank chamber 5. Consequently, the refrigerant gas under high pressure in the discharge chamber 26 flows into the crank chamber 5 via the supply passage 34, raising the pressure in the crank chamber 5. The difference between the pressure in the crank chamber 5 and the pressure in the cylinder bores 22 therefore increases and the inclination of the swash plate 10 becomes smaller.
As the inclination of the swash plate 10 becomes smaller, the spool 14 is pushed toward the positioning surface 18 with the pipe 20 and the ball bearing 16. When the shutter surface 19 of the spool 14 abuts against the positioning surface 18, the spool 14 blocks the suction passage 17 from the suction chamber 25. Consequently, the refrigerant gas in the external refrigeration circuit 37 does not flow into the suction chamber 25 and the circulation of the refrigerant gas through the compressor and the external refrigeration circuit 37 is stopped.
When the spool 14 abuts against the positioning surface 18, the inclination of the swash plate 10 is minimum. Since the minimum inclination of the swash plate 10 is slightly inclined from a position perpendicular to the axis L, the refrigerant gas is discharged into the discharge chamber 26 from the cylinder bores 22 even when the inclination of the swash plate 10 is minimized. Even when the inclination of the swash plate 10 is minimized, therefore, a pressure difference exists between the discharge chamber 26, the crank chamber 5 and the suction chamber 25. With the inclination of the swash plate 10 at the minimum, therefore, a circulation path circulating gas between the discharge chamber 26, the supply passage 34, the crank chamber 5, the passage 32, the pressure release hole 33, the suction chamber 25, and the cylinder bores 22 is formed in the compressor. The refrigerant gas circulates along this circulation path, and the lubricating oil suspended in the refrigerant gas lubricates the internal parts of the compressor.
When the cooling load of the compressor increases from the above state, it appears as a rise in temperature in the evaporator 40. When the temperature detected by the temperature sensor 46 exceeds the predetermined value, the controller C excites the solenoid 28. When this excitation takes place, the supply passage 34 is closed to disconnect the discharge chamber 26 from the crank chamber 5. Under this situation, the refrigerant gas in the crank chamber 5 flows out to the suction chamber 25 via the passage 32 and the pressure release hole 33, and the pressure in the crank chamber 5 decreases. As a result, the inclination of the swash plate 10 shifts toward its maximum from its minimum.
As the inclination of the swash plate 10 is increased, the spool 14 is gradually separated from the positioning surface 18 by the spring force of the coil spring 15. During this separation, the amount of refrigerant gas that flows into the suction chamber 25 from the suction passage 17 gradually increases. As a result, the amount of the refrigerant gas drawn into the cylinder bores 22 from the suction chamber 25 also increases gradually, and the discharge displacement of the compressor increases gradually.
When the engine stops, the compressor stops running and the solenoid 28 is de-excited. Therefore, the inclination of the swash plate 10 shifts toward the minimum inclination. With the operation of the compressor stopped, the swash plate 10 is held at its minimum inclination.
In the present embodiment, introduction of the refrigerant gas from the external refrigeration circuit 37 to the suction chamber 25 is allowed and prevented, by the spool 14 moving between the open position and the closed position in accordance with the tilting of the swash plate 10. When the spool 14 moves between the open position and the closed position, the spool 14 slides in the axial direction of the shutter chamber 13 with respect to the inner surface of the shutter chamber 13. The rotation of the drive shaft 6 may be transmitted to the spool 14 through the ball bearing 16 and cause slight rotation of the spool 14. In such cases, the spool 14 rotates against the inner surface of the shutter chamber 13.
However, in the present embodiment, a fluororesin coating 41 is provided on the outer surface of the large diameter portion 14a of the spool 14, which contacts the inner surface of the shutter chamber 13. Therefore, the friction coefficient of the outer surface of the large diameter portion 14a is decreased. This reduces the sliding resistance between the outer surface of the large diameter portion 14a and the inner surface of the shutter chamber 13. Accordingly, the spool 14 moves smoothly inside the shutter chamber 13, and prevents increased friction of the spool 14 against the inner surface of the shutter chamber 13. As a result, the durability of the spool 14 is improved. This leads to an increased compressor life. In addition, the smooth movement of the spool 14 allows the swash plate 10 to tilt with less resistance.
when the spool 14 moves to the closed position, there is a possibility that the spool 14 may rotate together with the drive shaft 6, with the spool 14 abutted against the positioning surface 18. However, in the preferred embodiment, the fluororesin coating 42 is provided on the shutter surface 19 of the spool 14, which comes into contact with the positioning surface 18. Thus, this decreases the friction coefficient of the shutter surface 19 and reduces the sliding resistance between the shutter surface 19 and the positioning surface 18. Accordingly, although the spool 14 is rotated while contacting the positioning surface 18, increased friction does not take place between the spool 14 and the positioning surface 18.
When operation of the compressor is resumed after having been stopped, there are times when the lubricant inside the compressor is washed away by liquefied refrigerant and discharged to the external refrigeration circuit. This causes insufficient lubrication inside the compressor. In such cases, the coatings 41, 42, provided on the external circumferential surface of the spool 14 and the shutter surface 19, prevent increased friction.
The coating 42 of the shutter surface 19 of the spool 14 absorbs dimensional manufacturing errors and microscopic deformation of the shutter surface 19 and the positioning surface 18. Thus adhesion between the shutter surface 19 and the positioning surface 18 is improved. This enhances the sealing effectiveness between the shutter surface 19 and the positioning surface 18. As a result, when the spool 14 abuts against the positioning surface 18, the suction passage 17 is positively disconnected from the suction chamber 25. This ensures blockage of the circulation of the refrigerant gas between the external refrigeration circuit 37 and the compressor.
A second embodiment of the present invention will now be described with reference to FIG. 4. In the second embodiment, as shown in FIG. 4, a coating 41 is provided on the inner surface of the shutter chamber 13 instead of the outer circumferential surface of the spool 14. In addition, a coating 42 is provided on the positioning surface 18 instead of the shutter surface 19 of the spool 14. This structure achieves the same advantageous effects of the first embodiment.
Furthermore, the present invention may be modified as described below.
(1) In each of the above embodiments, resins such as FEP (copolymer of 4-ethylene fluoride and 6-propylene fluoride) and PTFE (polytetrafluoroethylene) may be used, instead of ETFE, as the fluororesin coatings 41 and 42.
(2) The coating 41 may be provided on both the outer surface of the spool 14 and the inner surface of the shutter chamber 13. The coating 42 may also be provided on both the shutter surface 19 of the spool 14 and the positioning surface 18. This structure reduces friction.
(3) A coating may be provided on the entire outer surface of the spool 14. This simplifies coating operations, in comparison with separate coatings applied on the large diameter portion 14a of the spool 14 and on the shutter surface 19.
(4) The coating 41 may be provided by attaching, for example, a cylindrical body made of FEP on the large diameter portion 14a of the spool 14 or fitting the cylindrical body into the inner surface of the shutter chamber 13. The coating 42 may also be provided by attaching an annular plate made of FEP on the shutter surface 19 or the positioning surface 18.
Therefore, the present examples and embodiments are to be considered as illustrative and not restrictive, and the invention is not to be limited to the details given herein, but may be modified within the scope of the appended claims.
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A compressor has a housing body, a drive shaft, a swash plate, and a piston. The swash plate converts rotation of the drive shaft to reciprocating movement of the piston in a cylinder bore. The piston compresses gas supplied to the cylinder bore from an external circuit via a suction chamber and discharges the compressed gas to a discharge chamber. The swash plate is tiltable with respect to a plane perpendicular to the longitudinal axis of the drive shaft according to differential pressure between the crank chamber and the suction chamber. The swash plate controls the displacement of the compressor based on the inclination thereof. A spool is movable longitudinally between a first position and a second position in response to the inclination of the swash plate. The spool connects the external circuit with the suction chamber in the first position and disconnects the external circuit from the suction chamber in the second position. The housing body has a surface slidably engaged by the spool. A coating layer is provided on at least one of the spool and the slide surface to reduce frictional resistance occurring due to the sliding movement of the spool on the slide surface. A second coating layer is provided on an end surface of the spool to lubricate and thereby reduce frictional resistance with the housing surface along the periphery of the suction passage leading into the shutter chamber occurring due to rotation of the spool, and also to improve the seal between the end surface of the spool and the housing when in the second position closing off the suction passage.
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BACKGROUND OF THE INVENTION
[0001] The present invention relates to improved coating compositions containing microparticles, preferably glass beads having an average diameter up to about 70 microns, which are preferably coated to improve their dry flowability and to reduce their wet-out capability. These properties within resinous binder materials affect microparticle bonding properties within plastic coatings, paints, and similar compositions. This invention also relates to methods for producing coating compositions for producing resinous bodies which contain coated particles that are more tightly bonded within the composition, resulting in compositions having improved bonding properties for substrates.
[0002] 1. Field of the Invention
[0003] The present invention is concerned with improving the adhesion or bonding properties of microparticles such as glass beads, plastic beads, glass flakes, mica and similar pigment and color-enhancing materials within coating compositions, and improving the adhesive or bonding properties of such compositions for substrates such as metal automobile bodies, appliances, etc. Particles of such materials normally have a surface affinity and attraction for each other, particularly in the presence of moisture, so that they have poor flowability properties in bulk, such as from within a container. This results in the particles forming clusters, agglomerates or build-ups of a plurality of flakes, beads or other particles, which interfere with their handling properties, metering properties and the aesthetic nature of the particles for their desired characteristics, such as color uniformity, light reflection or refraction and similar properties, as well as avoidance of significant reduction in impact strength caused by the addition of agglomerates to plastics.
[0004] 2. State of the Art
[0005] It is known to improve the dispersing, orienting or migration properties of the aforementioned microparticles within liquid plastic compositions, such as solvent coating compositions, whereby the microparticles are not merely wetted and drawn by gravity down into the depth of the coating.
[0006] It is known to add thickeners such as asbestine pigment to resinous paint solutions containing microbeads to prevent or retard settling during the spray-application of reflective highway paints, and to coat the beads with thin organophilic films to improve adhesion or affinity or wettability of the beads in the resinous binder material, and reference is made to U.S. Pat. No. 2,574,971.
[0007] It is also known to coat microbeads with adhesion promoters, including organosilanes, such as 3-aminopropyltriethoxysilane or 3-methacryloxypropyltrimethoxysilane to insure that the microbeads are firmly secured to the substrate in a retroreflective screen printing ink having a resinous binder material. Reference is made to U.S. Pat. No. 5,650,213.
[0008] Also, U.S. Pat. No. 5,736,602 discloses the addition of colloidal suspending agents to curable thermosetting resinous coating compositions containing glass microspheres to retain the glass beads in suspension in the resin binder system.
[0009] It is also known to coat glass microparticles to render them repellent to each other, to avoid clustering and agglomeration and to improve flowability, and/or to make them repellent to resinous or plastic binder materials to improve their distribution and/or predetermine their location within resinous or plastic coatings, extrusions or molded products, and reference is made to co-pending application U.S. Ser. No. 09/752,305 filed on Dec. 12, 2000.
[0010] Said co-pending application relates to the coating of microparticles such as glass beads, plastic beads, glass flakes, mica, pigments and similar color-enhancing particulate materials, particularly glass microspheres having average particles sizes up to about 75μ, preferably from about 1μ up to about 20μ, with materials which bond to the particles' surfaces and impart flowability to the particles in bulk and from their packages containing uniform dispersions of the particles in compositions, particularly compositions containing plastic or resinous binder materials for applying liquid coatings, or for extruding plastic rods, fibers or films, or for molding plastic bodies.
[0011] According to a preferred embodiment of said co-pending application, free-flowing self-repelling microparticles are produced which can be easily compounded into conventional resinous or plastic compositions, without the need for thickening or viscosity-increasing additives, but said particles are also repelled to predetermined and/or different degrees by compositions into which they are compounded, most particularly by the plastic or resinous binder materials thereof, to produce compositions in which the glass microbeads are not as strongly bonded as desired, and compositions which have reduced adhesiveness or bonding properties for substrates.
[0012] These adhesion problems apply generally to all coating compositions or paints containing glass microbeads and resinous binder materials. Glass microbeads have smooth, inert surfaces which repel the resinous binder material which is intended to bind the microbeads within the coating composition and to bond the dried coating, such as paint, to the substrate.
SUMMARY OF THE INVENTION
[0013] The present invention relates to providing novel microbead coating compositions having improved binding properties for the glass microbeads suspended therein, which compositions also have superior bonding properties for substrates so as to be resistant to peeling or flaking therefrom after drying. According to the present invention these novel binding and bonding properties are unexpectedly produced by the addition of microparticles of ground rubber to microbead coating compositions containing a resinous binder material and, optionally, other color-enhancing particles such as pigments, glass flakes, metallic flakes, mica and similar materials as disclosed in co-pending U.S. Ser. No. 09/752,305, discussed supra. The rubber particles, known as crumb rubber and pelletized rubber are commercially-available from Spreerelast GmbH, Ardennering, Germany under the trademark Relaston® MT and DT (devulkanized) having grain or particle sizes of 100μ, 120μ, 150μ, 160μ, 180μ, and larger. The rubber particles are produced cryogenically by freezing and grinding scrap tire rubber elastomer to the desired grain size and smooth surface. Particles having a grain size of 150μ or less are preferred for use in the present compositions. They have the appearance of a powder and are gray in color.
[0014] The rubber particles are effective in amounts between about 2% up to about 40% by weight of the total solids content of the coating composition, more preferably between about 5% and 20%. The darkish color and opacity of the rubber particles reduces or tones down the normal light-refracting, light-diffusing properties which the microbead composition has in the absence of the rubber particles, but the formed coatings or paints are aesthetically-attractive since they exhibit a depth of color, particularly when pigmented black or gray or silver and used as automobile paints.
[0015] More importantly, the present coating compositions exhibit excellent affinity for substrates to which they are applied, such as by spray painting, and bond strongly thereto when dried and/or heat-cured /or baked. Similarly, the microparticles are strongly bonded within the formed coatings by the resinous binder material and are resistant to separation therefrom, which can result in cracking, and flaking of the coating. It is unclear how or why the rubber microparticles modify the present compositions to improve the affinity of the glass microbeads for the resinous binder material and to increase the affinity of the coating composition or paint for substrates, but it appears that the rubber particles have a greater affinity for the resinous binder material and for the glass microbeads than these materials have for each other, thereby linking these materials to each other and to the coated substrates.
[0016] The present coating or paint compositions are formulated as high solids content, heat-curable, compositions containing embedded or encapsulated light-refractive colorless and/or tinted transparent glass beads, preferably between about 10 to 20 microns diameter, rubber microparticles, and one or more color-enhancing agents such as pigments, dyes, aluminum flakes, colored aluminum flakes, mica, metallized mica, holographic flakes, phosphorescent glass beads and similar light-enhancing agents. Alternatively, some of the color enhancing agents may be present in a colored base coating over which the glass bead-embedded coating composition is applied, to cause light reflected by the base coat to be refracted and dissipated across the transparent glass bead layer, whereby the intensity and richness of the color or appearance of the combined layers is substantially enhanced.
[0017] While the present paint compositions may contain some beads which are opaque and/or retroreflective, such as hemispherically- or fully-metallized glass beads, or phosphorescent-coated beads, it is essential that a substantial content of the beads comprises light-refractive, clear or tinted glass beads which function as light diffusers within the semi-opaque translucent paint layer to scatter direct and indirect light, including colored light, in all directions across the paint layer.
[0018] The scattered light may have the color of a reflective base layer, or may become colored or enhanced by absorption and/or reflection by the rubber particles and/or by a color-enhancing ingredient also embedded within the beaded paint layer, such as metal flakes, mica, pigment, metallized beads or glass beads containing color, pigment, luminescent or phosphorescent coatings, holographic flakes or similar color enhancing additives. The present light-refractive paint layers scatter light across the paint layer, depending upon their degree of translucency, due to the content of fully-embedded transparent or translucent beads, and do not merely retro-reflect or focus applied light directly back to the source. To the contrary, the translucent glass beads refract direct and indirect light in all directions through the paint layer, to enhance the depth and richness of the color(s) of the paint layer or the underlying base layer.
[0019] The present bead-containing refractive paint compositions may be based upon volatile organic solvents, water or may be solvent-free spray powder compositions.
[0020] In the case of volatile organic solvent compositions, the solids content is maintained high, above about 60% solids, which is facilitated by the content of the rubber microparticles and the inert, solid glass beads, pigment, aluminum flakes, mica, etc., and the film-forming binder material comprises a heat-curable resin system such as a polyester, acrylic, polyurethane or epoxy resin system including a cross-linking agent.
[0021] The present paint compositions may be water-borne or aqueous compositions comprising a water soluble heat-curable, cross-linking binder material such as an acrylic acid ester resin, a methacrylic acid ester resin, a polyurethane polymer, or the like, the pelletized rubber, the microbead mixture comprising clear or translucent refractive beads and color enhancers such as pigmented, dyed, phosphorescent or luminescent reflective beads, pigments, metal flakes, mica, holographic flakes, etc.
[0022] In another embodiment of the invention the present compositions contain a volatile organic solvent or vehicle, but are prepared as high solids compositions containing the pelletized rubber, the refractive glass beads, color enhancers and a minor amount of the resinous binder material and solvent or vehicle.
DETAILED DESCRIPTION
[0023] The most critical component of the present light-transmissive compositions is the mixture of pelletized rubber, and resinous binder/microbeads material. The microbeads comprise (a) translucent, preferably optically-clear, light-refracting microbeads; optionally (b) one or more color-enhancing additives such as reflective microbeads which are coated with or encapsulate a reflective material, such as aluminum microbeads or aluminum-coated glass microbeads, or which are coated with or encapsulate colored dye or pigment or luminescent or phosphorescent materials, or consist of pigments, dyes, metal flake, mica or holographic flake, to lend color, depth and intensity to the paint coatings.
[0024] The pelletized rubber particles or powder comprise ground elastomeric tire scrap preferably having particle sizes up to about 150μ, preferably devulcanized. Such particles, known as ground rubber crumb, or pelletized rubber, are produced by cryogenic grinding processes and are commercially-available.
[0025] The resinous film-forming binder materials are as discussed hereinbefore.
[0026] The present refractive microbeads preferably are glass bead mixtures having different particle sizes and different indexes of refraction. However, the maximum diameter of the refractive beads including refractive clear and/or colored beads preferably is at least 10% less than the thickness of the cured paint layer, and preferably is within the range of 10 and 20μ for automotive paints.
[0027] The microbeads may be formed in conventional manner from known glass compositions such as silica glass, quartz, soda-lime glass, electroconductive glass, etc. The beads may be cast from molten glass compositions applied to corresponding cavities on a drum or plate, or by spraying of the molten composition through a nozzle for air cooling, or by any of the conventional processes currently used to produce commercially-available clear or tinted glass microbeads.
[0028] The light-refractive beads must be light-transmissive and preferably are optically clear and have an index of refraction of from about 1.5 to 2.5, preferably 1.9 to 2.1 and mixtures thereof.
[0029] The optional light reflective color-enhancing beads may be optically-opaque, preferably vacuum-metallized, or phosphorescent-or luminescent-coated glass microspheres, which reflect or emit and disperse light from their surfaces into and through the refractive microbeads, or against the rubber microparticles and color enhancing pigments, dyes, flakes, etc., and through the refractive microbeads in the form of scattered or dispersed colored light which gives added depth and intensity to the visual appearance and color of the paint layer.
[0030] In the case of luminescent, electroluminescent or phosphorescent reflective beads, the beads are surface coated with, or encapsulate, conventional luminescent, electroluminescent or phosphorescent compositions known to the art and, where necessary, are electroconductive.
[0031] The present paint compositions provide a novel and unexpected advantage with respect to the inclusion of mica as the color-enhancing particles. Mica is a preferred additive to conventional automotive paints since it imparts a pearlescent appearance. However because of the flat, lamelliform structure of mica crystals, the mica particles sometimes protrude at the dried paint surface to form imperfections or “fish eyes”. The mixture of pelletized rubber, glass beads and mica particles avoids these problems since the paint flows or levels to provide surface pattern control in which the mica particles are retained within the paint layer.
[0032] The common element of all of the present pelletized rubber/ bead-containing compositions is the matrix or binder material for the light refracting, dispersing and enhancing microbead mixture.
[0033] Most commonly the present compositions are volatile vehicle-based coating compositions which are applied to a substrate, such as a light-diffusive, light-refractive paint composition applied to an anti-corrosion primed metallic automotive surface or to a colored base coating thereon, and dried. Such coating compositions may comprise water-soluble curable binder materials such as acrylic ester resins or polyurethane polyester resins. Such aqueous compositions generally contain about 60% to 70% water and 30% to 40% solids which includes between 10% and 20% of the refractive microbead mixture, 2% to 40% of the pelletized rubber, 5% to 15% of the binder resin and the remainder consisting of one or more optional color-enhancing additives for imparting desired properties to the paint.
[0034] The formulation and application of the present compositions, such as paints for automobiles, boats, airplanes, appliances and a variety of other uses will be apparent to those skilled in the art in the light of the present disclosure.
[0035] The present paint coatings may comprise a single light-refractive color layer covered by a clear top-coat, or a colored base layer covered by a light-refracting tint layer and a clear top-coat.
[0036] In the case of automotive paints, the base metal body is first bathed or showered with a corrosion-resisting conversion coating or electrocoat, such as of zinc or iron phosphate or chromate and dried in an oven.
[0037] Subsequently a primer coating may be applied by dipping or flow coating, using a resinous binder of epoxy or alkyd polyester in organic solvent, followed by baking to harden the primer layer.
[0038] Next, the paint layer is sprayed over the primer layer, either as a single curable resinous paint layer or as a color-containing curable resinous base layer covered by a curable resinous bead-containing light-refracting tint layer. Each layer is baked to heat-cure the resinous binder material.
[0039] Finally a clear, colorless or tinted curable resinous top-coat is applied and baked to provide a hard protective, glossy exterior surface layer over the paint layer(s).
[0040] The preferred curable resinous binder system of the present coatings comprises the incorporation of both a cross-linkable polymer and a cross-linking agent which is reactive with groups on the polymer during heating or ultraviolet exposure to cure the polymer to a clear, hard, glass-like condition.
[0041] Water-based acrylic ester polymer/melamine-formaldehyde cross-linking resin mixtures provide curable binder material coatings having good resistance to ultraviolet light. Similar systems based upon organic solvent-soluble acrylic polymers and aldehyde resins are also suitable.
[0042] Solvent-based polyurethane coatings are also suitable, comprising a urethane prepolymer containing free isocyanate groups, as a polyisocyanate cross-linking agent, and an active hydrogen-containing polymer such as an —OH terminated polyester or polyether polymer.
[0043] A further advantage of the present glass-containing paint compositions, aside from the fact that the glass beads are inert, increase the solids content of the paint, and are easily reclaimable and recyclable, is that they provide the paint compositions with excellent spreadability, flow and leveling properties for ease and efficiency of application and surface pattern control.
[0044] The present pelletized rubber/glass bead paints containing color enhancers such as metallic flakes, colored metallic flakes and/or mica flakes, and colored mica flakes, provide richer, deeper automotive body colors and high specular flash or light scattering on the face of the color, i.e., when viewed directly, and a translucent rich deep elegant contrast when viewed at an angle, such on contoured body surfaces.
[0045] The content of the rubber particles and the glass spheres must be controlled to optimize the surface color quality, and varies with the paint color. With silver-colored or gray-colored metallic paints, the pelletized rubber and glass bead content each should be in the range of 5-10% by weight of the cured paint, preferably about 7%, whereas with darker colored paints the pelletized rubber and glass bead content should be in the range of 10-20% each by weight of the cured paint, preferably 12-15% each.
[0046] The following examples illustrate specific pelletized rubber/bead-containing paint compositions of different types coming within the present invention. It should be understood that such compositions are given by way of illustration only, and should not be considered limitative. In all cases, the layers are applied to conversion-coated or primed surfaces and are covered by conventional clear, glossy top coatings as currently used in the automotive paint industry.
EXAMPLE 1
[0047] A red-colored metallic paint layer is applied in the form of two coatings, namely a metallic flake base coating and a red tint overcoating containing the rubber particles and clear glass beads. The base coating comprises:
Base Coat Ingredient Parts by Volume phthalocyanine blue 3.4 bright coarse aluminum flake 145.0 blue color-coated flake 16.8 medium aluminum flake 50.6 blue-toned graphite 1.7 polyester/acrylic resin binder 202.4
[0048] The base composition is sprayed onto a primed metal auto body section and dried in a flash booth at 70-75° F., 63-68% humidity. The dried part is moved to a color bake oven and the paint is baked at 250° F. for 20-30 minutes to form a 1-mil thick base layer before application of the following tint coating thereover.
Tint Coat Ingredient Parts by Volume clear glass beads (10μ) 100 pelletized rubber (120μ 10 red toner 10 violet toner 9 clear resin and binder 300
[0049] The tint-coated part is dried and then bake-cured in the same manner as the base coated part to form a 4-mil tint coat layer, and a final clear top coat of heat-curable resin is applied, dried and bake-cured to form a durable, chip-resistant, smooth, glossy outer surface layer, also having a thickness of about 1-mil.
EXAMPLE 2
[0050] This example illustrates a single paint composition containing the light refractive beads, pelletized rubber and the color-enhancing agents for producing a light-refracting metallic gray paint layer.
Ingredients Parts by Volume med. aluminum flake 40.0 carbon black 150.0 phthalocyanine blue 20.0 Hostaperm Violet 15.0 glass beads 12μ, (1.9 + 2.1 RI) 20.0 pelletized rubber (120μ) 20.0 curable binder 180.0
[0051] The paint composition is sprayed over a primer-coated auto body part, dried and bake-cured in the same manner as in Example 1, to form a light-refractive color-enhancing paint layer having a thickness of about 1-mil (25μ). A final clear top-coat is applied and cured, as in Example 1, to form the durable, chip-resistant, smooth, glossy outer surface layer.
EXAMPLE 3
[0052] This example is similar to Example 1 in that it relates to the application of a base layer and the subsequent application of a bead-containing, pelletized rubber-containing tint layer thereover. However the base layer has a greenish color and the tint layer contains phosphor-coated (strontium sulfide) glass beads.
Base Layer Ingredients Parts by Volume phthalocyanine green (yellow shade) 10.9 phthalocyanine green (blue shade) 10.9 light chrome yellow 15.1 white pigment 344.4 black pigment 0.8 curable resin binder 37.8
[0053] The base layer is dried and bake-cured to a 1-mil thickness as in Example 1, and then spray-coated with the following tint layer:
Ingredients Parts by Volume gold mica 46.7 phosphorous beads 32.2 clear glass beads (10-20μ) 30.0 pelletized rubber (120μ) 20.0 curable resin binder 311.0
[0054] The tint layer is also dried and bake-cured to a 1-mil thickness, and then sprayed with a curable resinous clear top coat to provide the outer protective glossy surface layer.
EXAMPLE 4
[0055] This example is similar to Example 2 in that it relates to the application of a single paint layer containing pelletized rubber, glass beads and blue color-enhancing agents.
Ingredients Parts by Volume phthalocyanine blue 100 Hostaperm Violet 20 carbon black 125 fine blue mica 3 glass beads (12μ, 1.9 + 2.1 RI) 15 pelletized rubber (120μ) 10 curable resin binder 160
[0056] The paint composition is spray-applied over a primed auto body part, dried and bake-cured as in Example 1, to form a refractive blue paint layer of about 1-mil thickness. The final clear top-coat is applied and bake-cured to form the protective, glossy surface layer.
[0057] In all cases, the formed paint layers are not retroreflective. Light applied thereagainst is refracted, scattered and diffused to some extent through the layers and enhanced by the colors of the pelletized rubber, pigments, dyes and flakes contained within the layers to provide a rich, deep appearance to the color of the paint. The glass microbeads are more firmly bound to the resin binder materials within the various layers, and the bead layers are more firmly bonded to the substrates due to the inclusion of the pelletized rubber.
[0058] While the present invention has been described in terms of specific embodiments and combinations, it will be appreciated that the invention is not limited to the particular examples presented herein, and that the scope of the protection is defined in the attached claims.
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Novel microbead coating compositions having improved binding properties for the glass microbeads suspended therein, which compositions also have superior bonding properties for substrates so as to be resistant to peeling or flaking therefrom after drying. These novel binding and bonding properties are unexpectedly produced by the addition of microparticles of ground rubber, crumb rubber or pelletized rubber, to microbead coating compositions containing a resinous binder material and, optionally, other color-enhancing particles such as pigments, glass flakes, metallic flakes, mica and similar materials.
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FIELD OF THE INVENTION
The present invention relates to airfoils, and more particularly, to airfoils for gas turbine engines and other turbomachines.
BACKGROUND
Airfoils for gas turbine engines and other turbomachines remain an area of interest. Some existing systems have various shortcomings, drawbacks, and disadvantages relative to certain applications. Accordingly, there remains a need for further contributions in this area of technology.
SUMMARY
One embodiment of the present invention is a unique airfoil for a turbomachine. Another embodiment is a unique gas turbine engine. Yet another embodiment is a method for manufacturing an airfoil for a turbomachine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for airfoils and turbomachinery. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.
BRIEF DESCRIPTION OF THE DRAWINGS
The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein:
FIG. 1 schematically illustrates some aspects of a non-limiting example of a lift engine system in accordance with an embodiment of the present invention.
FIG. 2 illustrates some aspects of a non-limiting example of an airfoil in accordance with an embodiment of the present invention.
FIGS. 3 and 4 illustrate some aspects of a non-limiting example of an airfoil in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
For purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nonetheless be understood that no limitation of the scope of the invention is intended by the illustration and description of certain embodiments of the invention. In addition, any alterations and/or modifications of the illustrated and/or described embodiment(s) are contemplated as being within the scope of the present invention. Further, any other applications of the principles of the invention, as illustrated and/or described herein, as would normally occur to one skilled in the art to which the invention pertains, are contemplated as being within the scope of the present invention.
Referring to the drawings, and in particular FIG. 1 , there are illustrated some aspects of a non-limiting example of a lift engine system 10 in accordance with an embodiment of the present invention. Lift engine system 10 is configured to provide propulsive thrust for an aircraft 12 , such as a short takeoff and vertical landing (STOVL) aircraft. Lift engine system 10 includes turbomachinery in the form of a gas turbine engine 14 and a lift fan system 16 . In other embodiments, gas turbine engine 14 may be employed without lift fan system 16 as a propulsion engine for one or more various types of aircraft. In still other embodiments, gas turbine engine 14 may be any gas turbine engine, e.g., adapted for use as an aerospace engine, a marine engine, an industrial engine or the like, and may be in the form of a turbofan engine, a turboshaft engine, a turboprop engine, a turbojet engine or a hybrid engine.
In one form, gas turbine engine 14 includes a fan 18 , a compressor 20 , a combustor 22 and a turbine 24 . Lift fan system 16 includes a lift fan 26 , a shaft system 28 , and a lift thrust output system in the form of a vanebox 30 . In various embodiments, fan 18 , compressor 20 and turbine 24 may include one or more rotors, each of which may have one or more blade stages and vane stages. The number of rotors and stages for each of fan 18 , compressor 20 and turbine 24 may vary with the needs of the particular application. Lift fan 26 is coupled to gas turbine engine 14 via shaft system 28 .
Fan 18 is configured to pressurize air received at the inlet of engine 14 . Compressor 20 is in fluid communication with fan 18 , and is configured to compress air discharged by fan 18 . Combustor 22 is in fluid communication with compressor 20 , and is configured to receive the air discharged by compressor, add fuel, and combust an air fuel mixture. Turbine 24 is in fluid communication with combustor 22 , and is configured to receive the hot gases exiting combustor 22 , and to extract energy therefrom to power fan 18 , compressor 20 and lift fan 26 via one or more shafts (not shown). Turbine 24 may also be configured to provide power for other components (not shown). Power is supplied from gas turbine engine 14 to lift fan 26 via shaft system 28 . Lift fan 26 is adapted for mounting to aircraft 12 , and discharges air through vanebox 30 to provide thrust e.g., for STOVL aircraft 12 , which in some embodiments may be vectored thrust.
Gas turbine engine 14 and lift fan system 16 employ many airfoils in the form of blades and vanes in order to pressurize, expand and/or direct the flow of air and/or combustion products in and through engine 14 and lift fan system 16 . The airfoils are used in fan 18 , compressor 20 , turbine 24 , lift fan 26 and vanebox 30 . It is often desirable that the airfoils be light in weight in order to manage the weight of engine 14 and system 16 . In addition, in many cases, it is desirable that the airfoils be robust for operational purposes, but also less prone to damage downstream components should an airfoil separate from its mounting structure and pass through downstream components of part or all of engine 14 and/or lift fan system 16 . Accordingly, embodiments of the present invention envision airfoils having a foam core, such as a metal foam core, with a composite skin surrounding the foam core. Such an airfoil may weigh less than conventional solid metal or hollow metal airfoils.
Referring to FIG. 2 , some aspects of a non-limiting example of an airfoil 40 in accordance with an embodiment of the present invention is depicted. Airfoil 40 includes a metal foam core 42 and a composite skin 44 disposed over metal foam core 42 , forming an airfoil shape. A portion of composite skin 44 is removed in the illustration of FIG. 2 in order to illustrate aspects of metal foam core 42 and composite skin 44 . In one form, metal foam core 42 is 10% dense, that is, 10% of the density of a solid metal formed of the same material. In other embodiments, other density values may be employed. The type of metal used in metal foam core 42 may vary with the needs of the application. In one form, metal foam core 42 is formed of a titanium alloy. In other embodiments, other metals, alloyed or not, may be employed, e.g., an aluminum alloy.
In one form, airfoil 40 is a fan blade adapted for use in fan 18 . In other embodiments, airfoil 40 may be employed as a compressor 20 airfoil, a turbine 24 airfoil, a lift fan 26 airfoil or a vanebox 30 airfoil, and may be a blade or a vane. In one form, airfoil 40 is configured to be more readily “sliced up” by downstream components of engine 14 and/or lift fan system 16 , as compared to solid or hollow metal airfoils (having on the order of 100% density of the metal) in the event the airfoil separates from its mounting and is ingested by one or more downstream components. In one form, extending from airfoil 40 is an attachment feature 46 configured to attach airfoil 40 to a fan 18 rotor (not shown).
In one form, attachment feature 46 is formed as an extension of metal foam core 42 and composite skin 44 . In various such embodiments, attachment feature 46 may have a different metal density than metal foam core 42 , e.g., may be fully dense or may transition from one density value to another with increasing proximity to metal foam core 42 . In other embodiments, attachment feature 46 may be formed separately and affixed to airfoil 40 using any suitable bonding or other material joining technique.
In one form, metal foam core 42 is a closed-cell foam. In other embodiments, metal foam core 42 may be an open-cell foam or a combination of open-cell foam and closed-cell foam. In one form, metal foam core 42 is formed as an airfoil shape (except attachment feature 46 ). In other embodiments, metal foam core 42 may be formed as another shape, and subsequently machined or otherwise processed into an airfoil shape.
Metal foam core 42 includes a plurality of outermost voids 48 . In one form, voids 48 are formed as part of the foam structure of metal foam core 42 . In other embodiments, voids 48 may be formed in metal foam core 42 subsequent to metal foam core 42 being formed. In one form, composite skin 44 includes a composite material layer 50 that extends into and at least partially fills some or all of outermost voids 48 , affixing composite skin 44 to metal foam core 42 . Bonding agents may or may not be used to increase the bond strength, depending upon the application. In one form, composite material 50 is a polyamide material. In other embodiments, other composite materials may be employed, e.g., depending upon mechanical, thermal and/or aerodynamic loading, and/or ambient conditions at the location in engine 14 and/or lift fan system 16 where airfoil 40 is intended to operate. In one form, composite material layer 50 is glass-filled. In other embodiments, composite material layer 50 may employ other fillers in addition to or in place of glass. In still other embodiments, composite material layer 50 may not employ any fillers.
In one form, composite skin 44 includes another composite material layer 52 overlaying composite material layer 50 . In one form, composite material layer 52 is a carbon-fiber composite having a carbon fabric included therein. In other embodiments, composite material layer 52 may be one or more other types of composite materials. In one form, composite layer 52 is bonded to composite material layer 50 . In one form, composite layer 52 is configured to reinforce composite material layer 50 . In other embodiments, composite material layer 52 may also or alternatively be configured otherwise. For example and without limitation, composite material layer 52 may be configured for erosion and/or corrosion protection. Although described herein as being bonded to composite material layer 50 , in other embodiments, composite material layer 52 may be bonded directly to metal foam core 42 . For example, some embodiments may include composite layer 52 as part of composite skin 44 , but without also having composite layer 50 as part of composite skin 44 .
Airfoil 40 may be manufactured by forming a metal foam core 42 into an airfoil shape. For example and without limitation, metal foam may be formed into an airfoil via the use of a mold, may be formed into a rough shape and subsequently machined or otherwise processed into an airfoil shape, or may be formed into an airfoil shape via a freeform manufacturing technique, such as a stereolithography technique. In other embodiments, metal foam core may not have an airfoil shape or a complete airfoil shape, in which case composite skin 44 may be used to form the airfoil shape. Metal foam core 42 is manufactured to include outermost voids 48 .
After metal foam core 42 is formed into an airfoil shape, composite skin 44 is affixed to metal foam core 42 . Composite material layer 50 is formed by directing composite material, e.g., polyamide, into outermost voids 48 , at least partially filling voids 68 , and thereby affixing composite skin 44 to metal foam core 42 . In various embodiments, only some of voids 48 are filled or partially filled, e.g., depending on the size of the void. In one form, the composite material is injection molded into voids 48 . In other embodiments, other techniques may be employed to direct the composite material of composite layer 50 into outermost voids 48 . Composite material layer 50 may be filled (e.g. glass-filled) or may be unfilled. In one form, composite layer 52 , e.g., a carbon fiber composite, is formed and bonded onto composite material layer 50 . In various other embodiments, composite layer 52 may not be employed, or may be bonded or otherwise affixed to metal foam core 42 .
Referring to FIGS. 3 and 4 some aspects of a non-limiting example of an airfoil 60 in accordance with an embodiment of the present invention is depicted. Airfoil 60 includes a metal foam core 62 and a composite skin 64 disposed over metal foam core 62 , forming an airfoil shape. A portion of composite skin 64 is removed in the illustration of FIG. 4 in order to illustrate aspects of metal foam core 62 and composite skin 64 . In one form, metal foam core 62 is 10% dense. In other embodiments, other density values may be employed. The type of metal used in metal foam core 42 may vary with the needs of the application. In one form, metal foam core 42 is formed of a titanium alloy. In other embodiments, other metals, alloyed or not, may be employed, e.g., an aluminum alloy.
In one form, airfoil 60 is configured as a vane that is configured for use in vanebox 30 . In other embodiments, airfoil 60 may be employed as a compressor 20 airfoil, a turbine 24 airfoil, a lift fan 26 airfoil, and may be a blade or a vane. In one form, extending from airfoil 60 is an attachment feature 66 configured to attach airfoil 60 to vanebox 30 . In one form, attachment feature 66 is formed separately and affixed to airfoil 60 , e.g., using a suitable bonding or other material joining technique. In other embodiments, attachment feature 66 may be formed as an extension of metal foam core 62 and composite skin 64 . In such embodiments, attachment feature 66 may have a different metal density than the metal foam 62 , e.g., may be fully dense or may transition from one density value to another with increasing proximity to metal foam core 62 . In one form, metal foam core 62 is a closed-cell foam. In other embodiments, metal foam core 62 may be an open-cell foam or a combination of open-cell foam and closed-cell foam. In one form, metal foam core 62 is formed as an airfoil shape (except attachment feature 46 ). In other embodiments, metal foam core 62 may be formed as another shape, and subsequently machined or otherwise processed into an airfoil shape.
Metal foam core 62 includes a plurality of outermost voids 68 . In one form, voids 68 are formed as part of the foam structure of metal foam core 62 . In other embodiments, voids 68 may be formed in metal foam core 62 subsequent to metal foam core 62 being formed. In one form, composite skin 64 includes a composite material layer 70 that extends into and at least partially fills some or all of outermost voids 68 , affixing composite skin 64 to metal foam core 62 . Bonding agents may or may not be used to increase the bond strength, depending upon the application. In one form, composite material 70 is a polyamide material. In other embodiments, other composite materials may be employed, e.g., depending upon mechanical, thermal and/or aerodynamic loading, and/or ambient conditions at the location in engine 14 and/or lift fan system 16 where airfoil 60 is intended to operate. In one form, composite material layer 70 is glass-filled. In other embodiments, composite material layer 70 may employ other fillers in addition to or in place of glass. In still other embodiments, composite material layer 70 may not employ any fillers.
In one form, composite skin 64 includes another composite material layer 72 overlaying composite material layer 70 . In one form, composite material layer 72 includes a carbon fabric in a carbon-fiber composite. In other embodiments, composite material layer 72 may be one or more other types of composite materials. In one form, composite layer 72 is bonded to composite material layer 70 . In one form, composite layer 72 is configured to reinforce composite material layer 70 . In other embodiments, composite material layer 72 may also or alternatively be configured otherwise. For example and without limitation, composite material layer 72 may be configured for erosion and/or corrosion protection. Although described herein as being bonded to composite material layer 70 , in other embodiments, composite material layer 72 may be bonded directly to metal foam core 62 . For example, some embodiments may include composite layer 72 as part of composite skin 64 , but without also having composite layer 70 as part of composite skin 64 .
In one form, airfoil 60 may be manufactured in the same manner set forth above with respect to airfoil 40 . In other embodiments, airfoil 60 may be manufactured using other processes and techniques.
Embodiments of the present invention include an airfoil for a turbomachine, comprising: a metal foam core; and a composite skin disposed over the metal foam core and forming an airfoil shape.
In a refinement, the composite skin includes a carbon fiber composite.
In another refinement, the carbon fiber composite includes a carbon fabric.
In yet another refinement, the metal foam core has a plurality of outermost voids, and the composite skin includes a first composite material extending into and at least partially filling at least some of the plurality of outermost voids.
In still another refinement, the composite skin includes a second composite material overlaying the first composite material.
In yet still another refinement, the second composite material is a carbon fiber composite.
In an additional refinement, the second composite material is bonded to the first composite material.
In a further refinement, the first composite material includes a polyamide.
In a yet further refinement, the polyamide is glass filled.
In a still further refinement, the turbomachine is a vanebox, and the airfoil is a vane configured for use in the vanebox.
In a yet still further refinement, the airfoil further comprises at least one attachment feature configured to attach the airfoil to a component of the turbomachine.
Embodiments of the present invention include a gas turbine engine, comprising: at least one of a fan and a compressor; a combustor in fluid communication with the compressor; and a turbine in fluid communication with the combustor, wherein at least one of the fan, compressor and the turbine include an airfoil having a metal foam core and a composite skin disposed over the metal foam core.
In a refinement, the airfoil is a fan blade.
In another refinement, the metal foam core has an airfoil shape.
In yet another refinement, the metal foam core is a closed-cell foam.
In still another refinement, the composite skin includes a first composite material reinforced by a second composite material.
In yet still another refinement, the first composite material is a polyamide material.
In an additional refinement, the second composite material includes a carbon fabric.
In a further refinement, the airfoil is configured as a vane.
Embodiments of the present invention include a method for manufacturing an airfoil for a turbomachine, comprising: forming a metal foam core into an airfoil shape; and affixing a composite skin to the metal foam core.
In a refinement, the metal foam core is formed to include a plurality of outermost voids, and wherein the composite skin is formed at least in part by injection molding a composite material into at least some of the plurality of outermost voids.
In another refinement, the method further comprises bonding a carbon fiber composite to the composite material.
In yet another refinement, the metal foam core is machined into an airfoil shape.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment(s), but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as permitted under the law. Furthermore it should be understood that while the use of the word preferable, preferably, or preferred in the description above indicates that feature so described may be more desirable, it nonetheless may not be necessary and any embodiment lacking the same may be contemplated as within the scope of the invention, that scope being defined by the claims that follow. In reading the claims it is intended that when words such as “a,” “an,” “at least one” and “at least a portion” are used, there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. Further, when the language “at least a portion” and/or “a portion” is used the item may include a portion and/or the entire item unless specifically stated to the contrary.
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One embodiment of the present invention is a unique airfoil for a turbomachine. Another embodiment is a unique gas turbine engine. Yet another embodiment is a method for manufacturing an airfoil for a turbomachine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for airfoils and turbomachinery. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.
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FIELD OF THE INVENTION
[0001] The invention refers to a powder coating composition providing a highly reproducible colour strength and colour position accuracy in the final coating.
BACKGROUND OF THE INVENTION
[0002] Pigmented powder coating compositions that meet a customer's colour specifications require a labour-intensive multi-step approach during their preparation, for example, batch mixing, extrusion, further processing and coating of powder samples, measurements of colour, laboratory tests, adjustment of the raw materials and re-mixing and re-processing, re-mixing with extra pigment. In general, it is difficult to achieve the desired colour without correction steps because of batch to batch pigment variability and equipment performance variability.
[0003] One way to solve this problem is the provision of a limited number of stored, intermediate coating compositions which are combined, depending on the desired colour effect, and corresponding to the specific customer needs. Thus, there exists in the literature a number of examples describing dry-blends of powder coating compositions by mixing powder coating intermediate compositions having different colours, for example, WO 99/50360, EP-A 826 746, JP-A 11279464, JP-A 11286635.
[0004] WO 98/36030 describes a coloured powder coating composition consisting of two or more colour formulations which are dry-mixed together. The particles of one formulation are coloured and the particles of the other formulation have a different colour, or are optionally colourless. The composition forms a continuous coating, and the differences in colour cannot be differentiated by human eye.
[0005] WO 99/23068 discloses a process wherein different coloured fine powder compositions are compacted resulting in powders of uniform colours.
[0006] JP-A 52-47 031 describes the production of thermosetting powder paints, whereby the thermosetting resin, colour pigments and various additives are melt dispersed in a heating kneader. The preliminary dispersion composition of each original colour is mixed to obtain the desired colour, and the curing agent and optionally resins and additives are added to the mixture which is then melt mixed and pulverized.
[0007] However, these processes require the storage and production of appropriate finished coating compositions, e.g. pigmented coating powders or pigment-coated resins in a large number of different primary colours, in order to be able to produce the broadest range of final product colours. In addition, a uniform colour often cannot be obtained if the particle sizes of the different powder compositions to be mixed have too high value such as higher than, for example, 20 micrometers. Additionally, the production of such finely divided coating powders is energy-intensive and may create both dust explosion hazards and can also be inhaled by operators if not handled properly. Also, the coating powders will tend to absorb water if not stored properly, and coating powders with variable water content cannot be accurately measured in order to achieve a desired product colour, and agglomerated coating powders cannot be mixed as efficiently in order to produce a high quality final product.
[0008] JP 2001-288414 refers to a method for producing a powder coating which is suitable for the production of small batches of various colours using a few types of primary colour pellets and dry-mixing the types of pellets in suitable amounts to create the pre-determined coating colour followed by co-milling thereof. The powder pellets are produced by mixing, extruding and grinding of powder coating components with pigments and additives to obtain pellets having a specific colour.
[0009] WO 2006/047238 discloses the use of liquid pigment dispersions in which pigment is dispersed in a liquid polyester resin or optionally in a dispersing resin and solvent. This approach could not produce a high quality consistent product without multiple intermediate colour checks and adjustments to the powder coating during processing. For example, blue formulations could show weaker colour strength in a polyurethane (PUR) chemistry, but stronger colour strength in hybrid chemistry, compared to a traditional formulation. The converse could be true for formulations using a red pigment. Thus it is not proven that the use of pigmented liquid dispersions described led to improved colour strength in the final powder coating. Additionally, the use of liquid dispersing resins having a low glass transition temperature necessitates the use of further additives in the powder coating formulation to increase the glass transition temperature of the final product to give the required storage stability for the coating powder.
[0010] WO 2007/087169 and WO 2007/140131 refer to dispersions of polymer-enclosed colour-imparting particles for incorporating into powder coating compositions. The particles need to be prepared by polymerisation enclosure.
SUMMARY OF THE INVENTION
[0011] The present invention provides a powder coating composition prepared from a combination, the combination comprising:
[0012] A) at least one binder resin and, optionally at least one curing agent,
[0013] B) at least one calibrated pigmented liquid, based on at least one pigment, and,
[0014] C) optionally, at least one pigment and/or extender and/or additive.
[0015] The powder coating composition of the invention provides a precise colour of the coatings having a desired colour with high colour stability. Therefore there is no need for additional adjustment tests or re-working procedures, and, therefore, it makes it possible to offer efficient, small-batch manufacture of custom colours, for example, to match a swatch of fabric supplied by a customer. The resulting coatings fulfil the requirements regarding properties of common powder coatings such as the desired colour, gloss, film appearance and mechanical properties. The colour and appearance of the final product is also less sensitive to variations in process equipment geometry and process conditions, thus ensuring that the powder coating can be produced at multiple locations whilst still delivering consistent product.
DETAILED DESCRIPTION OF THE INVENTION
[0016] The features and advantages of the present invention will be more readily understood, by those of ordinary skill in the art, from reading the following detailed description. It is to be appreciated those certain features of the invention, which are, for clarity, described above and below in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any sub-combination. In addition, references in the singular may also include the plural (for example, “a” and “an” may refer to one, or one or more) unless the context specifically states otherwise.
[0017] Slight variations above and below the stated ranges can be used to achieve substantially the same results as values within the ranges. Also, the disclosure of these ranges is intended as a continuous range including every value between the minimum and maximum values.
[0018] Conventional binder resins and curing agents known to a person skilled in the art may be used as component A) of the invention.
[0019] Examples of binder resins are polyester resins, urethane resins, polyester urethane resins, polyester epoxy resins, epoxy resins, (meth) acrylic resins, alkyd resins and melamine/urea/formaldehyde resins.
[0020] Suitable polyester resins may be either acid or hydroxyl functional, depending on the cross-linking chemistry used. For example, hydroxyl functional polyester resins may have a hydroxyl number in the range of, for example, 30 to 350 mg KOH/g resin, and carboxyl functional polyester resin may have an acid number in the range of, for example, 10 to 200 mg KOH/g resin. The polyesters may be produced in a conventional manner by reacting of one or more aliphatic, aromatic or cycloaliphatic di- or polycarboxylic acids, and the anhydrides and/or esters thereof with polyalcohols, as is, for example, described in D. A. Bates, The Science of Powder Coatings , volumes 1 & 2, Gardiner House, London, 1990, and as known by the person skilled in the art.
[0021] Suitable (meth)acrylic resins include, for example, copolymers prepared from alkyl(meth)acrylates with glycidyl(meth)acrylates and olefinic monomers; functionalized resins such as polyester (meth)acrylates, epoxy (meth)acrylates, urethane (meth) acrylates, glycidyl(meth)acrylates.
[0022] The term (meth) acrylic is respectively intended to mean acrylic and/or methacrylic.
[0023] Crystalline and/or semi-crystalline binder resins are also usable which have a Tm (melting temperature) in the range of e.g., 50 to 200° C., determined by means of differential scanning calorimetry (DSC).
[0024] Preferred is the use of polyester resins, polyester urethane resins, polyester epoxy resins and/or (meth) acrylic resins. Particularly preferred is the use of polyester resins and/or (meth) acrylic resins.
[0025] The content of at least one binder resin in component A) of the combination according to the invention can be in a range between 50 and 100 parts per weight, preferably, between 60 and 97 parts per weight, parts per weight based on component A), depending on the cross-linking chemistry of the binder resin and curing agent of component A).
[0026] The binder resins may comprise self cross-linkable resins containing cross-linkable functional groups known by a person skilled in the art. In this case, no curing agent needs to be used in the composition according to the invention.
[0027] The final product can also be cross-linked by using at least one curing agent (cross-linker) in component A) suitable for the binder resins known by a person skilled in the art. Examples of curing agents are blocked cycloaliphatic, aliphatic or aromatic polyisocyanates; agents containing epoxy groups, such as, for example, triglycidyl isocyanurate (TGIC); polyglycidyl ethers based on diethylene glycol; glycidyl functionalized (meth) acrylic copolymers; agents containing amino, amido, (meth)acrylate and/or hydroxyl groups, for example hydroxyl alkylamide crosslinker, as well as vinyl ethers. Furthermore, conventionally curing agents such as, dicyanodiamide hardeners, carboxylic acid hardeners or phenolic hardeners are usable.
[0028] For example, the ratio of a polyester resin as binder resin to TGIC as curing agent can be between 90:10 and 98:2; the ratio of a polyester resin as binder resin to PRIMID® (EMS-Chemie AG, Germany) as curing agent can be, for example, 90:10 and 97:3; the ratio of an acid functional polyester as binder resin to a glycidyl functional (meth)acrylate resin as curing agent can be, for example, between 50:50 and 70:30. The amounts may be above or below these ranges, depending, for example, on the binder resin properties, on the acid number of the polyester and/or on the epoxy-equivalent weight of the (meth)acrylate resin, as known to a person skilled in the art.
[0029] The content of component A) in the combination used for preparation of the composition according to the invention is 20 to 99.9 weight %, preferably 30 to 90 weight % and most preferably 40 to 80 weight %, the weight % based on the total weight of the combination A) to C) of the invention.
[0030] The combination according to the invention comprises as component B) at least one calibrated pigmented liquid. Pigmented liquid means that these are liquids, solvent-borne and/or water-borne, as solution and/or dispersion, comprising at least one pigment. Preferred is the use of at least one water-borne calibrated pigmented liquid.
[0031] The at least one calibrated pigmented liquid may contain at least one pigment, and may comprise at least one polymeric dispersant for stabilisation the pigment in the liquid.
[0032] The calibrated pigmented liquids are produced in such a way that they have and provide a highly reproducible colour strength and well-defined colour information in order to provide a desired colour or defined colour specification of the coating based on the powder coating composition of the invention, independently of the used pigment or source of pigment, and independently of the used processing techniques by using, for example, different types of extruders or different extruder processing. This also means that a minimal amount of pigment is required and that the variations in the manufacturing process will not give differences in colour strength, as would occur if the powder coating formulation contains solid pigments or pigment agglomerate-containing liquids. For example, the extruder shear history, for example, by using different extruder geometries, will not affect the calibrated pigmented liquids nor change the final powder coating colour.
[0033] Calibrated pigmented liquids used in liquid coating businesses, thus referred to as “tints”, can be used for this invention. The benefit of the calibration is that a recipe that uses these calibrated pigmented liquids will give a well-defined final coating colour when known masses or volumes of raw materials are mixed together, irrespective of the natural colour strength of the pigment used to formulate this calibrated pigmented liquids. The calibrated pigmented liquids have proven storage stability and can thus be manufactured in large volumes and easily stored at local manufacturing sites.
[0034] The calibrated pigmented liquids are processed to maximise the colour strength that the pigments can achieve, and the colour strength and colour position are adjusted to a defined colour specification by a combination of dilution and addition of pigments and, when required, of other colorants.
[0035] Colour strength and colour position can be determined in terms of lightness (L), degree of red/green (a*) colour and degree of blue/yellow colour (b*) according to the CIE 1976 L*a*b* standard colour space method, which is an international standard for colour measurement, known at a person skilled in the art. Differences between the reference sample and a particular colour sample are shown as an absolute difference in L, a* and b* and are written as Delta L, Delta a and Delta b. Delta e is the total relative error and is the deviation in colour strength (lightness, L) and colour position (red/green and blue/yellow offset) of the colour values of a reference sample. Delta e can be calculated from Delta L, Delta a and Delta b according to the formula Δe=(ΔL+Δa+Δb) 1/2 .
[0036] The calibrated pigmented liquids contain between 0.5 and 80 weight % of at least one pigment, preferably between 3 and 50 weight % of at least one pigment, and they may contain between 10 and 90 weight % of water and/or solvent, the weight % based on the calibrated pigmented liquids. The calibrated pigmented liquids may optionally contain polymeric dispersants and other additives to improve the stability of the calibrated pigmented liquids, for example by preventing agglomeration or settling of the polymeric dispersants, as well as to give other desired properties of the calibrated pigmented liquids, such as a desired mixture viscosity.
[0037] The calibrated pigmented liquids can be prepared by combination of dilution and addition of pigments and, when required, of other colorants. For that, a solid pigment is transferred into a pigment liquid by mixing, for example in a mill, with water and/or solvent, optionally containing the above mentioned additives. The resulted pigment liquid provides a colour which can be determined by the above described CIE 1976 L*a*b* standard colour space method, and the colour is then adjusted (calibrated) to a defined colour specification. Such adjustment (calibration) can be carried out by addition of additional water and/or solvent and optionally additional additives, mentioned above, as well as optionally by addition, in a range of 0 to 20 weight % based on the calibrated pigmented liquid, of other pigments and/or colorants such as pigment dispersions, to result into the calibrated pigmented liquid.
[0038] Examples of colouring pigments used in the calibrated pigmented liquids are colour-imparting and/or special effect-imparting pigments and/or fillers (extenders). Suitable colour-imparting pigments are any conventional coating pigments of an organic or inorganic nature considering their heat stability which must be sufficient to withstand the curing conditions of the powder coating composition of the invention. Examples of inorganic or organic colour-imparting pigments are titanium dioxide, micronized titanium dioxide, carbon black, iron oxide, azo pigments, and phthalocyanine pigments. Examples of special effect-imparting pigments are metal pigments, for example, made from aluminium, copper or other metals, interference pigments, such as, metal oxide coated metal pigments and coated mica. Examples of usable extenders are silicon dioxide, aluminium silicate, barium sulfate, calcium carbonate, magnesium carbonate and micronized dolomite.
[0039] The at least one polymeric dispersant of the calibrated pigment liquid can be one or more resins formed by polymerisation and/or copolymerisation of monomers, particularly monomers having hydroxyl and/or acid functional groups, that lead to side groups along the polymer chain that stabilize the at least one pigment in the calibrated pigment liquid. The at least one polymeric dispersant can be resins having a sufficiently high glass transition temperature to give a stable final powder coating composition of the invention having little or no glass transition temperature modifiers. Examples of polymeric dispersants are resins formed by copolymerisation of hydrophobic and hydrophilic monomers. Preferred is the use of colourless polymeric dispersants.
[0040] It is possible to use at least one calibrated pigmented liquid, but it is also possible to use at least two calibrated pigmented liquids having different colour data, for example, different RAL colours. RAL colours mean the standard of the RAL (Reichsausschuss fuer Lieferbedingungen) Institute for colours, known to a person skilled in the art.
[0041] The content of component B) in the combination used for preparation of the composition according to the invention depends on the colour strength of the calibrated pigmented liquid or calibrated pigmented liquids that are used and the desired colour provided by the powder coating composition prepared from the combination of this invention. The content is typically 0.1 to 80 weight %, preferably 0.3 to 70 weight % and most preferably 0.5 to 45 weight %, the weight % based on the total weight of the combination A) to C) of the invention.
[0042] At least one pigment and/or extender and/or additive can be used as component C) of the combination according to the invention.
[0043] Examples of pigments are those as already mentioned above. Common extenders and additives are agents known to a person skilled in the art and may be solid or liquid. Examples of extenders (fillers) are barium sulfate, clay, calcium carbonate. Examples of additives are levelling agents, rheological agents such as highly dispersed silica or polymeric urea compounds, thickeners, for example based on partially cross-linked, carboxy-functional polymers or on polyurethanes, defoamers, wetting agents, anticratering agents, degassing agents, thermolabile initiators, antioxidants and light stabilizers based on HALS (hindered amine light stabilizer) products, tribo-charging agents, accelerators, initiators, inhibitors and catalysts. The additives can be used, in conventional amounts known to the person skilled in the art, for example, 0.01 to 10 weight %, based on the total weight of the combination.
[0044] The content of component C) in the combination used for preparation of the composition according to the invention will be between 0 and 50 weight %, based on the total weight of the combination A) to C) of the invention.
[0045] In particular, the present invention provides a powder coating composition prepared from a combination, the combination comprising
A) 20 to 99.9 weight %, preferably 30 to 90 weight % and most preferably 40 to 80 weight %, of at least one binder resin and, optionally at least one curing agent, B) 0.1 to 80 weight %, preferably 0.3 to 70 weight % and most preferably 0.5 to 45 weight %, of at least one calibrated pigmented liquid, based on at least one pigment, and, C) 0 to 50 weight % of at least one pigment and/or extender and/or additive, the weight % based on the total weight of the combination A) to C).
[0049] The combination of A) to C) of the invention can be a mixture which is dried and further processed in order to give the final powder coating composition of the invention. The final powder coating composition will have between 0 and 7 weight %, preferably less than 3 weight % of residual water and/or solvent, the weight % based on the total weight of the powder coating composition.
[0050] The powder coating composition of the invention may be prepared by conventional manufacturing techniques used in the powder coating industry. For example, the components A) to C) can be blended together to a mixture, and then the mixture is extruded, at a temperature at which cross-linking (curing) does not occur.
[0051] A pre-mixing of the components of the combination prior to extrusion and to further processing can be done. For example, component A) and component C) can be incorporated into component B) of the invention. Pre-mixing can also be done by adding component B) to one of component A) and C) or to a mixture of component A) and C).
[0052] Most or all of the water and/or solvent content of component B) can be removed during processing, preferably either before or during the extrusion process. Examples of the method for removal of this water and/or solvent are vacuum extrusion, batch heating with or without vacuum, spray drying and other techniques known at a person skilled in the art.
[0053] The extrusion process is known to a person skilled in the art. In the extruder the mixture is melted and homogenized at a temperature in a range of, for example, 30 to 170° C. The extruded material is then cooled on chill rolls and/or chill bands and is broken up into pre-powder particles, which can be in the form of chips or pellets, followed by grinding to form a finely divided powder with a typical particle size for a coating powder, for example, an average particle size of 20 to 200 μm, preferably 30 to 60 μm. The resulting finished powder coating composition is usable without any additional adjustment tests or re-working procedures. The liquid content of the final powder coating composition is in the range of 0 and 7 weight %, preferably less than 3 weight %, based on the total weight of the powder coating composition.
[0054] Furthermore, specific components of the composition according to the invention, for example, additives, pigment, extenders, may be processed with the finished powder coating particles after extrusion and grinding by a “bonding” process using an impact fusion. For this purpose, the specific components may be mixed with the powder coating particles. During blending, the individual powder coating particles are treated to softening their surface so that the components adhere to them and are homogeneously bonded with the surface of the powder coating particles. The softening of the powder particles' surface may be done by heat treating the particles to a temperature, e.g. the glass transition temperature Tg of the powder coating composition, in a range, of e.g., 50 to 60° C. After cooling the mixture the desired particle size of the resulted particles may be proceed by a sieving process.
[0055] The final powder coating composition of the invention may be applied by techniques known in the art to a substrate, e.g., metallic substrates, non-metallic substrates, such as, paper, wood, plastics, glass and ceramics, including heat-sensitive substrates, and curing the applied composition. The final powder coating composition of the invention may be applied as a one-coating system or as coating layer in a multi-layer film build, onto pre-heated or non-pre-heated substrates. The powder coating composition according to the invention can be applied directly on the substrate surface, which can be a degreased substrate surface, or on a substrate pre-treated by techniques known in the art. The powder coating composition according to the invention can be applied also on a layer of a primer which can be a liquid or a powder based primer, for example, a conductive primer in case of coating of non-conductive substrates like wood or MDF.
[0056] The applied and melted powder can be cured by thermal energy. The coating layer may, for example, be exposed to convective, gas and/or radiant heating, e.g., infra red (IR) and/or near infra red (NIR) irradiation, as known in the art, to temperatures of, e.g., 100 to 300° C., preferably of 120 to 230° C. for convective thermal curing and preferably 200 to 280° C. for radiation heating processes (object temperature in each case). If the composition according to the invention is used together with unsaturated resins and, optionally photo-initiators or with unsaturated resin containing powders, dual curing may also be used. Dual curing means a curing method of the powder coating composition according to the invention where the applied composition can be cured, e.g., both by high energy radiation such as, e.g. ultra violet (UV) irradiation, and by thermal curing methods known by a skilled person.
[0057] The present invention is further defined in the following Examples. It should be understood that these Examples are given by way of illustration only. As a result, the present invention is not limited by the illustrative examples set forth herein below, but rather is defined by the claims contained herein below.
EXAMPLES
Example 1
Colour Values of Pigments of Prior Art, of Calibrated Pigmented Liquids and of Powder Coating Compositions According to the Invention
[0058] The colour values of four different samples of a solid violet pigment (Hostaperm-Violett RL Spezial, Clariant) are measured using the CIE 1976 L*a*b* standard colour space method. The colour values are measured relative to a solid painted panel that is treated as the reference colour sample. The different samples of the violet pigment, comprising rheological additives, differ in the time of preparation by the supplier. The colour values can be found in Table 1.
[0000]
TABLE 1
Pigment
Pigment
Pigment
Pigment
sample 1
sample 2
sample 3
sample 4
Delta L
−0.19
−0.24
−0.56
−0.2
Delta a
0
−0.98
−0.75
−0.55
Delta b
0.14
1.06
0.88
1.07
Delta e
0.24
1.46
1.28
1.22
[0059] The colour values are described in terms of lightness (L), degree of red/green (a*) colour and degree of blue/yellow colour (b*) according to the CIE 1976 L*a*b* standard colour space method. Differences between the reference sample and a particular pigment sample are shown as an absolute difference in L, a* and b* and are written as Delta L, Delta a and Delta b. Delta e is the total relative error and is the deviation in colour strength (lightness, L) and colour position (red/green and blue/yellow offset) of the colour values of a reference sample. Delta e can be calculated from Delta L, Delta a and Delta b according to the formula Δe=(ΔL+Δa+Δb) 1/2 .
[0060] As shown in Table 1 the average colour deviation Delta e is 1.05.
[0061] Four calibrated pigmented liquids are prepared from the pigment samples 1 to 4 of the violet pigment described above.
[0062] For that the solid violet pigment sample(s) is(are) first milled with 5 to 20 weight % water containing a polymeric dispersant, in a media mill. The material in the mill is processed until no further increase in colour intensity is possible. The colour of the resulted colour liquid (un-calibrated) is then measured and compared to a reference colour sample required for each particular calibrated pigment liquid (colour specification).
[0063] For colour matching, to meet the colour specification, additional water and colourless stabiliser additive are then added to the colour liquid for calibrated pigmented liquid 1. For calibrated pigmented liquids 2, 3 and 4 additional water and colourless stabiliser additive as well as violet pigment dispersion Cromax Pro Dark Violet (DuPont), in a range of 0.5 to 10 weight %, are added to the colour liquids, for colour matching. The resulted calibrated pigmented liquids 1 to 4 contain 80 to 90 weight % of water, based on the calibrated pigmented liquid. The colour values can be found in Table 2.
[0000]
TABLE 2
Calibrated
Calibrated
Calibrated
pigmented liquid 3
Calibrated
pigmented liquid 1
pigmented liquid 2
based on pigment
pigmented liquid 4
based on pigment
based on pigment
samples 2 and 3
based on pigment
sample 1
sample 2
(mixture 1:1)
sample 4
Delta L
0.24
0.19
−0.09
0.02
Delta a
0.08
0.25
0.22
0.01
Delta b
0.15
0.23
0.04
−0.11
Delta e
0.294
0.389
0.241
0.112
[0064] The colour values are measured as described above.
[0065] As shown in Table 2 the average colour deviation Delta e is 0.259.
[0066] A powder coating composition is prepared from each of the calibrated pigmented liquids 1 to 4 described above. Each calibrated pigmented liquid and the other components are mixed together and dried. The dried mixture is then extruded on a Buss extruder, under standard conditions, and the extrudate is cooled and milled to give a coating powder with an average particle size of between 40 and 60 micrometers. For measurement of the colour, each powder coating composition is sprayed onto a test panel and the panel is cured in an oven for 15 minutes at 180° C., giving a film thickness of between 60 and 80 micrometers. For the purposes of colour comparison, the panel produced from the powder coating composition 1 is defined as the standard (n/a), due to the colour values of the used pigment sample 1. The colour values can be found in Table 3.
[0067] The colour values are measured as described above.
[0068] As shown in Table 3 the average colour deviation Delta e is 0.526.
[0069] As it can be seen from Table 1 and Table 3 the use of the calibrated pigmented liquids has given a 50% reduction in the average colour deviation Delta e without any manual adjustment of the colour of the powder coating compositions, compared to the variability of the pigment samples 1 to 4, proving that a desired colour can be matched using the calibrated pigmented liquids in the powder coating compositions, without batch adjustment.
[0000]
TABLE 3
Powder Coating
Powder Coating
Powder Coating
Powder Coating
Composition
Composition
Composition
Composition
1
2
3
4
amounts in parts
amounts in parts
amounts in parts
amounts in parts
Components
per weight
per weight
per weight
per weight
polyester URALAC P 841
757.6
757.6
757.6
757.6
(DSM)
curing agent PRIMID XL 552
44
44
44
44
(EMS Chemie)
flow additive RESIFLOW
8.8
8.8
8.8
8.8
PV88 (Worlee Chemie)
BENZOINE
2.4
2.4
2.4
2.4
rheological additive LUVOTIX
8
8
8
8
R (Lehmann&Voss)
wax additive
6.4
6.4
6.4
6.4
stabiliser additive IRGAFOS
8
8
8
8
126 (Ciba)
Titanium dioxide pigment
285.13
285.13
285.13
285.13
TIPURE R706 dispersion
(DuPont)
Calibrated pigmented liquid 1
28.51
Calibrated pigmented liquid 2
28.51
Calibrated pigmented liquid 3
28.51
Calibrated pigmented liquid 4
28.51
Colour Values
Delta L
n/a
−0.18
−0.18
−0.68
Delta a
n/a
0.26
−0.06
0.41
Delta b
n/a
−0.33
0.11
−0.43
Delta e
n/a
0.457
0.219
0.903
Example 2
Colour Values of Powder Coating Compositions of Prior Art and According to the Invention
[0070] Two premixes of light blue colour are prepared by mixing together the components, see Table 4. Premix 1 is formulated using the solid pigment Irgazin Blue A3R N (Ciba) while
[0071] Premix 2 is formulated using a calibrated pigmented liquid of the pigment Irgazin Blue A3RN according to the invention. Premix 2 was dried as known in the art before being processed further.
[0072] Each premix is extruded once on a Buss extruder, under standard conditions. Half of each extruded sample is then extruded a second time, under same conditions, in order to increase the degree of shear history applied to each of the samples. This produces a total of four extruded samples which are then milled and applied to test panels, as mentioned above, for colour measurement. For the purposes of colour comparison, the panels produced from Premix 1 (1 extrusion) and Premix 2 (1 extrusion) are defined as standards (n/a). The colour values can be found in Table 5. The colour values are measured as described above.
[0000]
TABLE 4
Premix 1
Premix 2
amounts in parts
amounts in parts
Components
per weight
per weight
URALAC P 841
947
947
PRIMID XL 552
55
55
RESIFLOW PV88
11
11
BENZOINE
3
3
LUVOTIX R
10
10
wax additive
8
8
IRGAFOS 126
10
10
TIPURE R706
150.18
TIPURE R706 dispersion
356.45
Irgazin Blue A3RN (Ciba)
6.42
calibrated pigmented liquid
35.65
Cromax Pro Violet Blue (DuPont)
[0000]
TABLE 5
Premix 1
Premix 1
Premix 2
Premix 2
(1 extrusion)
(2 extrusions)
(1 extrusion)
(2 extrusions)
L*
62.18
61.77
58.68
58.71
a*
−4.97
−4.81
−4.05
−4.09
b*
−31.86
−32.16
−33.16
−33.16
Delta e
n/a
0.53
n/a
0.05
[0073] The colour measurements show that the composition based on Premix 2 including the calibrated pigmented liquid results in a 10-times lower average colour deviation Delta e after the extra extrusion step. This means that, at first, a desired colour can be matched without any manual adjustment, and, further, that this composition is less sensitive to the degree of shear applied during the manufacturing process.
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The invention provides a powder coating composition prepared from a combination, the combination comprising:
A) at least one binder resin and, optionally at least one curing agent, B) at least one calibrated pigmented liquid, based on at least one pigment, and, C) optionally, at least one pigment and/or extenders and/or additive.
The powder coating composition of the invention provides a precise colour of the coatings having a desired colour with high colour stability. Therefore there is no need for additional adjustment tests or re-working procedures, and, therefore, it makes it possible to offer efficient, small-batch manufacture of custom colours, for example, to match a swatch of fabric supplied by a customer.
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BACKGROUND OF THE INVENTION
My invention relates to roller gins.
In the art to which my invention relates it is well known that the efficiency of roller gins depends, in large measure, on removing the build-up of foreign matter on or adjacent the cutting edge of the knife which cooperates with the roll, the knife and roll forming the mechanism which removes lint from the seed cotton as it is fed to the apparatus. Attempts have been made to clean knives by intermittently blowing the trash from the knife cutting edge with blasts of air or the like. The assignee of this application owns U.S. Pat. No. 4,262,390 dated April 21, 1981, "ROLLER GIN AND FEED SYSTEM INCORPORATING THE SAME" which shows air cleaning of the knife. While the apparatus shown in the above patent is satisfactory, my present invention is an improvement over that apparatus and so far as I am aware, over all previous apparatus and processes for cleaning roller gin knives.
Briefly, my invention incorporates associating with the usual and customary parts of a roller gin means automatically to clean the knife, either intermittently or at predetermined, set intervals of time, by first stopping the feed to the gin and then releasing the pressure between the knife and roller, following which the roller is reversed for a few revolutions, thus causing trash such as cotton, leaf particles, etc. draped over the knife to be removed therefrom. While as will be explained hereinafter, there are other details to my improved process of operating roller gins with regard to the motion between the roller and knife for cleaning purposes, nevertheless the general concept of my invention is just as stated, namely, to reverse the direction of rotation of the roll thus to remove trash from the cutting edge of the knife.
SUMMARY OF THE INVENTION
In view of the foregoing it will be seen that broadly it is the object of my invention to provide a roller gin and process of operating the same in which the gin automatically and at predetermined intervals if desired interrupts its ginning operation and goes through a blade cleaning sequence.
My invention also has for an object the provision of the process of operating a roller gin embodying a sequence in which the mechanism feeding the seed cotton to the gin comes to a halt, after which the gin is permitted to run for a length of time to clear all unginned cotton between the knife-roll and feeder mechanism. Then, the motor driving the gin is deenergized allowing the ginning roll to coast to a stop utilizing the friction between roll and knife for braking following which the ginning roll is slightly retracted to remove the knife from major friction contact with the roll. The motor is again started in reverse and allowed to obtain full speed. With the ginning roll going full speed it is advanced to create full friction contact with the knife while the motor driving the ginning roll continues to run in reverse for a preset time. This removes the lint which is draped over the cutting edge of the knife or otherwise clinging to the knife adjacent its edge. The motor driving the gin is again deenergized allowing the ginning roll to coast to a stop utilizing the friction between roll and knife for braking. The ginning roll is now retracted to remove the knife friction, the motor driving the ginning roll is started in the forward direction and allowed to obtain full speed whereupon the roller is brought back into ginning contact with the knife, thus completing one cycle in the cleaning operation.
As will hereinafter appear, the description of the apparatus given in this application is in accordance with that shown and described in the aforesaid U.S. Pat. No 4,262,390 dated April 21, 1981. However, as those skilled in the art become aware of my improvement it will be apparent that the same may be applied to roller gins constructed differently, certainly in detail, from the one shown in said patent.
BRIEF DESCRIPTION OF DRAWINGS
Apparatus illustrating a roller gin incorporating my invention and which may also be used to carry out my improved process is shown in the accompanying drawings forming a part of this application in which:
FIG. 1 is an end elevational view looking at one end of a roller gin and feeder combination, the feeder section being shown partly in cross section;
FIG. 2 is an end elevational view looking at the apparatus from the end opposite that of FIG. 1;
FIG. 3 is a vertical sectional view of the roller gin indicated in the drawings by the numeral 13;
FIG. 4 is an end elevational view of one of the mechanisms for movably mounting one end of the gin roll shaft, the knife, holder, etc., being in cross section;
FIG. 5 is a view corresponding to FIG. 4 and showing the mechanism for moving the opposite end of the ginning roll shaft with the knife out of contact with the roll;
FIG. 6 is a partial, diagrammatic sectional view of the ginning roll and the mechanism shown in FIGS. 4 and 5, removed from the gin structure itself; and,
FIG. 7 is a wholly diagrammatic wiring diagram.
DETAILED DESCRIPTION
Referring now to the drawings for a better understanding of my invention, as stated, I will describe the same in association with a more or less standard roller gin feeder combination. Thus, at 10 I show a seed cotton feeder to which seed cotton is delivered from a conveyor-distributor, not shown, through a chute indicated at 11. The feeder 10 delivers the cotton to be ginned to a roller gin indicated generally in FIGS. 1 and 2 by the numeral 13. A suitable conveyor is located beneath the gin to carry away seed. The lint removed from the seed is discharged from the back of the gin through a lint flue 15 having a suction fan 16 connected thereto. See FIG. 3.
Referring still to FIG. 3 it will be understood that the gin embodies the usual framework or box-like enclosure 17. Mounted in the gin 13 is a ginning roll 18 the outer surface of which is covered with a belting-like material 19 as is understood in the art. The ginning knife is indicated at 21 and is mounted on relatively heavy supporting framework 22 which spans the gin from end to end so that the knife 21 is coextensive in length with the roll 18. At 23 I show what is known in the trade as a rotor bar and which is driven in the direction of arrow 24. The bar 23 also is substantially the length of the roller 18 and knife 21.
At 26 I show a guide plate which is adjustable toward and from the roller 18 and the purpose of which is to direct the seed cotton down onto the rotating parts of the gin.
As understood, the entire roll 18 is so mounted that it may be moved into and out of operating or ginning contact with the knife 21. Thus, roller 18 is provided with a shaft 27. Each end of the shaft 27 is mounted in bearings 28. These bearings in turn are mounted on slide blocks or plates 29 and the blocks 29 are mounted in guides 31 suitably secured to the end framework of the gin structure.
At 32 and 33 we show pairs of fluid pressure cylinders, for instance, air cylinders, to which air under pressure may be supplied from lines 34. These cylinder pairs are suitably mounted on the gin framework so that the piston rods 36 thereof engage cross members 37 forming a part of the slide system for supporting the ends of the shaft 27. Thus, whenever pressure is applied to the cylinders 32 and 33 the roll 18 is pressed into ginning contact with the ginning knife. When pressure is released, due to the upward inclination of the slide assemblies, roll 18 moves by gravity downwardly and away from the knife 21 so that its surface 19 no longer engages the knife.
The feeder comprises a pair of feed rolls 42. These may be in the form of spiked members and they are driven by a variable speed electric motor, 43, through suitable chains 43a or the like, to rotate in the direction of the arrows, FIG. 1. Seed cotton is delivered downwardly between these rolls at a given rate as determined by the speed of the motor 43.
Immediately beneath the rolls 42 is a spike cylinder 44, the tips of the spikes 46 of which pass very closely adjacent the tips of the spikes of the rollers 42. Also mounted adjacent cylinder 44 is another spiked cylinder 47 and these two cylinders run over grids 48 and 49. Trash falling from the grids 48 and 49 is removed from the gin by a conveyor 51.
Driven in the direction of arrow 52 is an extractor saw 53. A rotary brush doffer 54 is associated with the lower periphery of the saw 53. A reclaimer saw 56 also is served by the doffer 54 generally in the customary fashion.
From the description so far given it will be seen that I have described a more or less standard roller gin-feeder combination. Thus, seed cotton enters between the rollers 42 which are driven in the direction of the arrows as indicated. The spiked cylinder 44 may be driven so that the periphery of its spikes travels faster than the rolls 42, whereby cotton is single locked as it exits from the rolls 42. This cotton is then discharge onto the grids 48 and 49 and then onto the saw 53, finally being doffed down the slide 57 located above the ginning mechanism. The various rotary mechanisms of the gin and feeder (except feed rolls 42) are driven by a motor 55 through the belts and chains shown in FIGS. 1 and 2.
Referring now to FIG. 7 I will now describe in diagrammatic fashion the electrical and other mechanisms associated with the mechanisms already described in order to cause the gin to be self-cleaning or, if desired, to permit the same to be cleaned whenever necessary. Of course, by "cleaned" I mean to remove trash which accumulates on or adjacent the edge of the knife, the presence of which causes a deterioration in the ginning of the cotton and excessive wear on the covering 19 of the ginning roll 18.
It will be understood that the cylinders 32-33 associated with each end of the shaft 27 supporting the ginning roll 18 are under control of a common solenoid valve indicated at 59 in the drawings.
As will now be explained, the motor 55, solenoid valve 59 and motor 43 are all under control of a "brain" or master control, timing and power supply mechanism detailed in FIG. 7. As shown in FIG. 7 power is supplied to the control mechanism by lines L 1 and L 2 . The power and control circuits are carried to the motor 55 through lines 61, to the solenoid valve 59 through lines 62 and to the feed motor 43 through lines 63, all connected to the control or "brain" now to be described.
The control mechanism includes, as indicated completely diagrammatically in FIG. 7, eight separate timing mechanisms which preferably are used to carry out my improved process and to operate the roller gin after the fashion of my invention. At 66 I show a timer which cycles the apparatus at preset times, for instance, each 30 minutes. That is to say, every time the timer 66 times out, the cycle hereinafter described is initiated so that the gin becomes "self-cleaning" at preset time intervals. The timing out of timer 66 closes a set of contacts 67 and opens a set of contacts 68. The opening of contacts 68 deenergizes the motor 43 which as will be recalled controls the feeding rotation of the feed rollers 42. The closing of contacts 67 energizes a time delay relay 69. Relay 69 is set to time out at an appropriate interval of time, for instance, ten seconds which permits the gin to clear all unginned cotton between the knife-roll and feeder mechanism. The timing out of relay 69 closes a set of contacts 70 which in turn energizes another control relay 71. Immediately upon the energization of relay 71 a set of contacts 72 opens, deenergizing the main drive motor 55, thus bringing the gin parts, including the roller 18, to a stop. After an interval of time, for instance two seconds, relay 71 times out, closing contacts 73. The closing of contacts 73 energizes relay 74 and this instantaneously opens a set of contacts 75, deenergizing another relay 76. The deenergization of relay 76 immediately opens a set of contacts 77 deenergizing the solenoid valve 59 and causing the cylinders 32-33 to retract the roller from the ginning position, that is, clear of the stationary knife 41. At this point in time all the moving parts of the system are at a standstill. After a time delay of about two seconds relay 74 closes a set of contacts 78 energizing another relay 79. The relay 79 is a time delay relay and controls five sets of contacts to wit, contacts 80, 81, 82, 84, and the contact shown in series with contact 72. Thus, energization of relay 79 instantaneously closes a set of contacts 80 energizing relay 76, thus initiating a five second time delay. Closing of contacts 81 starts motor 55 turning in the reverse direction, thus to drive the ginning roll 18 in the direction opposite the arrows shown in FIG. 3. At the end of the five seconds associated with relay 76, contacts 77 close energizing solenoid valve 59, moving the ginning roll back into ginning position as shown in FIGS. 3 and 4 of the drawings. The five second time delay just mentioned gives the roller time to come up to speed prior to being placed into ginning contact with the knife.
Recalling now that relay 79 was timed in while relay 76 was timing in, seven seconds after relay 76 timed in, relay 79 times in, thus closing a set of contacts 82. The closing of contacts 82 energizes another time delay relay 83, which relay may be set for a period of two seconds. At the same time contact 82 closes, another set of contacts 84 open, deenergizing the motor 55. Motor 55 coasts to a stop, it being noted that the roller 18 is in contact with the knife 21 which thus acts as a brake on the roller and all of the other parts driven by the motor 55. After two seconds elapsed time delay relay 83 opens a set of contacts 85 thus deenergizing solenoid valve 59. This permits the retraction of the roller from the knife, moving from the position of FIG. 4 to the position of FIG. 5. In this position of the parts all of the mechanisms are at rest, the roller being in the position shown in FIG. 5, that is, withdrawn from contact with the stationary knife 21. At the same time contacts 85 open, contacts 86 are closed energizing another relay 87. Two seconds after the energization of relay 87 contacts 88 open, thus deenergizing timer 66. Contacts 68 instantaneously close, starting feed roll motor 43. The system is now back in operation since deenergization of timer 66 has caused contact 67 to reopen, deenergizing relays numbered 69, 71, 74 and 79. Deenergization of relay 79 opens contact 82 thus deenergizing relay 83 which in turn instantaneously reopens contact 86, deenergizing relay 87. Contact 88 recloses upon the deenergization of relay 87. The entire circuit has thus been reset and another thirty-minute ginning program is initiated.
From the foregoing it will be seen that I have devised an improved roller gin and process for operating the same. It is the opinion of this applicant that the primary wear on the surfaces of the ginning rolls of gins of this type is not due to ginning of the cotton; on the other hand, it appears to be due to excessive friction of the knife on the surface of the roll. In view of the fact that the recovering of these rolls is extremely expensive and time-consuming, it is highly desirable to extend their life as long as possible. Therefore, with my improved gin and process the friction due to trash on the knife is eliminated effectively and periodically, and if desired, automatically. Obviously, if desired, the system may be equipped with a manual start switch indicated at 90 in the drawings. However, with the arrangement of switches, relays, etc., as shown in this disclosure, the system can be completely automated, thus resulting in a great saving of wear on the roll covering, increasing its life and thus improving the efficiency of the gin and the entire plant of which the gin forms a part.
While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof.
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Disclosed is an improved roller gin having means for cleaning debris from the knife, and a process of operating such gin. Specifically, the gin includes means to rotate the roll in reverse, periodically, if desired, whereby any cotton, leaf, or other trash draped over the knife is thrown off or discharged from the gin. Means also is disclosed to operate the gin and its feeder in a fashion to gin all cotton enroute from the feeder to the gin prior to the gin going through its cleaning operation.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is related to optical isolators for use in optical fiber communication and optical network technology, and more particularly to optical isolators which employ molded lenses.
2. Description of the Prior Art
In the field of optical fiber communications, problems with the performance of optical devices often arise. One such problem is caused by light reflecting off an end face or another part of an optical device. Such reflections can return to the light source, adversely affecting the light source and deteriorating the quality of communications. Another problem is caused by echoes of transmitted optical signals, which are caused by multiple reflections off the end face or another part of an optical device. The deterioration in performance of a light source due to the return of reflected light has been previously observed in connection with the stability of self-mode locking. Now, devices designed to eliminate reflected lights such as optical isolators, are used in optical fiber communication systems to prevent such deteriorated performance and eliminate reflected light.
FIG. 5 shown a conventional optical isolator as disclosed in U.S. Pat. No. 5,557,692. The optical isolator 80 comprises an input port 81 , an output port 82 and an isolating means 83 . The input port 81 comprises an input optical fiber 811 and a first Graded Index (GRIN) lens 812 . The output port 82 comprises an output optical fiber 821 and a second GRIN lens 822 . The isolating means 83 includes a first polarizer 831 , a second polarizer 832 and a liquid crystal cell 833 disposed in the path of the rays from the first polarizer 831 to the second polarizer 832 .
The conventional optical isolator 80 using GRIN lenses 812 , 822 as collimating elements has some disadvantages. Firstly, the GRIN lenses are made using the ion-exchange method. However, this method requires a long time and further steps of polishing after initial formation, so it is difficult and expensive to manufacture. Secondly, some chemicals used in the ion-exchange method contaminate the environment and endanger the fabrication workers.
The present invention overcomes the above-described disadvantages of conventional optical isolators by offering an optical isolator having molded lenses which yield higher performance at a lower cost. A copending application Ser. No. 10/172,232 with the same assignee and the same inventors as the present invention discloses similar technology applied to other types of optical components.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide an improved optical isolator which employs molded lenses as collimating elements.
Another object of the present invention is to provide an optical isolator having high precision lenses which are relatively environmentally friendly to produce.
A further object of the present invention is to provide an optical isolator which is easily and cheaply manufactured.
To solve the problems of the prior art and to achieve the objects set forth above, an optical isolator of the present invention comprises an input port, an isolating means, an output port and a mounting tube. The input port comprises a ferrule having an optical fiber, a molded lens, a sleeve and a metal holder. The optical fiber has an exposed end and the ferrule defines a through hole for receiving and fixing the optical fiber therein. The ferrule has a rearward face and a forward face. The forward face of the ferrule is ground at an oblique angle and is flush with the exposed end of the optical fiber. The molded lens is cylindrical in shape and has an oblique surface coinciding with that of the ferrule and the exposed end of the optical fiber. A gap is defined between the molded lens and the ferrule. The output port is similar to the input port. The isolating means includes a first polarizer, a second polarizer and a Faraday rotator disposed in the paths of the rays from the first polarizer to the second polarizer. Furthermore, the optical axis of the second polarizer is oriented 45 degrees with respect to the optical axis of the first polarizer. The isolating means is located in the path of light beams from the input port to the output port.
Since the present invention employs molded lenses as the collimating elements, the cost and environmental problems associated with GRIN lenses are mitigated and efficiency is improved.
Other objects, advantages and novel features of the present invention will be apparent from the following detailed description of the preferred embodiment thereof with reference to the attached drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional diagram of an optical isolator according to the present invention;
FIG. 2 is a cross-sectional view of an input port of the optical isolator of FIG. 1;
FIG. 3 is a cross-sectional view of a molded lens of the optical collimator of FIG. 2;
FIG. 4 is an essential optical paths diagram of the input port of FIG. 2; and
FIG. 5 is a schematic view of a conventional optical isolator.
DESCRIPTION OF THE PREFERRED EMBODIMENT
For facilitating understanding, like components are designated by like reference numerals throughout the preferred embodiment of the invention as shown in the various drawing figures.
Reference will now be made to the drawings to describe the present invention in detail.
Referring to FIG. 1, an optical isolator 100 in accordance with a preferred embodiment of the present invention comprises an input port 10 , an isolating means 30 , an output port 20 and a mounting tube 40 .
The input port 10 and the output port 20 are identical in construction. The input port 10 is described as an example. As shown in FIG. 2, the input port 10 comprises a molded lens 11 , a ferrule 12 , an optical fiber 13 , a sleeve 14 and a metal holder 15 .
The ferrule 12 is cylindrical in shape and is made of a ceramic, a metal or a plastic material. The ferrule 12 has a forward face 122 , a rearward face (not labeled) and a through hole 121 defined between the forward face 122 and the rearward face (not labeled). A diameter of the through hole 121 is slightly greater than a diameter of the optical fiber 13 . A conical opening (not labeled) coaxial with the through hole 121 is defined in the rearward face (not labeled). The optical fiber 13 with has an exposed end is preferably fixed in the through hole 121 with UV-cured epoxy or 353-ND epoxy. To improve optical performance, the forward face 122 of the ferrule 12 and the exposed end (not labeled) of the optical fiber 13 are ground and polished at an oblique angle relative to an imaginary plane constructed perpendicular to a longitudinal axes of the ferrule 12 . The angle is preferably between 6 and 8 degrees.
Referring to FIG. 3, the molded lens 11 is substantially cylindrical and has a uniform refractive index. A rearward face 112 of the molded lens 11 forms an oblique angle with an imaginary plane constructed perpendicular to a longitudinal axis of the molded lens 11 . The angle is preferably between 6 and 8 degrees and should be equal to the angle of the forward face 122 of the ferrule 12 . A forward face 111 of the molded lens 11 has an aspherical surface. The rearward face 112 and the forward face 111 are both coated with an antireflective coating to reduce reflection losses.
The molded lens 11 may be made entirely using conventional methods such as injection molding. Therefore the molded lens can be formed with a high quality surface and high surface accuracy, and requires no further preparatory operations, such as grinding or polishing. Time required to make the molded lens is short and the cost is low. Furthermore, the antireflective coatings applied to the two end faces of the molded lens do not influence the optical path of transmitted light beams since the molded lens has a uniform refractive index. Finally, the fabrication process does not contaminate the environment or endanger the fabrication workers.
The sleeve 14 receives the molded lens 11 and the ferrule 12 therein. The metal holder 15 covers on outer surface of the sleeve 14 to protect the input port 10 .
In assembly, the exposed end of the optical fiber 13 is coated with epoxy and is threaded through the conical opening and into the through hole 121 of the ferrule 12 . The ferrule 12 with the attached optical fiber 13 then have a corresponding end thereof ground to a same oblique angle as that of the molded lens 11 . The molded lens 11 and the ferrule 12 with the attached optical fiber 13 are arranged in the receiving cavity of the sleeve 14 so that the forward face 122 of the ferrule 12 is parallel to and separated from the rearward face 112 of the molded lens 11 by a narrow gap defined between the molded lens 11 and the ferrule 12 . This arrangement is designed to assure precise collimation of light beams coming from the optical fiber 13 . The metal holder 15 is attached to the sleeve 14 with epoxy.
As shown in FIG. 4, in the present invention, a focal point of the molded lens 11 is located at the point where the through hole 121 intersects with the forward face 122 of the ferrule 12 . Scattered light beams 16 emitted from the optical fiber 13 are refracted at the rearward face 112 of the molded lens 11 , then the light beams 17 are refracted again at the forward face 111 of the molded lens 11 to emerge as parallel light beams 18 from the molded lens 11 . The collimating process of the light beams in the input port 10 is accomplished.
Since optical paths are reversible in lenses, light beams from the isolating means 30 directed at a front end of the output port 20 and parallel to a longitudinal axis of the output molded lens (not labeled) can be focused to the exposed end of the output optical fiber (not labeled) at forward face of the output ferrule (not labeled) by the output molded lens (not labeled).
As shown in FIG. 1, the isolating means 30 comprises a first polarizer 31 , a Faraday rotator 32 , a second polarizer 33 , and a housing 34 . The first and second polarizers 31 , 33 are typically made of birefringent crystals, or may be another type of polarizer. The optical axis of the second polarizer 33 is oriented 45 degrees with respect to the optical axis of the first polarizer 31 . The Faraday rotator 32 is disposed in the paths of the light beams from the first polarizer 31 to the second polarizer 33 . The housing 34 holds the polarizers 31 , 33 and the Faraday rotator 32 together to achieve the isolating function.
In operation, the isolating means 30 is located in the path of light beams from the input port 10 to the output port 20 . In the forward direction, the first polarizer 31 of the isolating means 30 separates the incident light from the input port 10 into a first ray, which is polarized along the crystal's optical axis and which is called an extraordinary ray, and into a second ray, which is polarized in a direction perpendicular to the crystal's optical axis and which is called an ordinary ray. The light from the first polarizer 31 is then rotated by the Faraday rotator 32 , which rotates the polarized light by 45 degrees. The rotated light is then recombined by the second polarizer 33 and is then output from the output port 20 .
In the reverse direction, light from the output port 20 is separated by the second polarizer 33 into a first ray, which is polarized along the crystal's optical axis and which is called an extraordinary ray, and into a second ray, which is polarized in a direction perpendicular to the crystal's optical axis and which is called an ordinary ray. When passing back through the Faraday rotator 32 , the light in both rays is rotated 45 degrees. This rotation is nonreciprocal with the rotation of light in the forward direction, so that the ordinary ray from the second polarizer 33 is polarized along the optical axis of the first polarizer 31 and the extraordinary ray from the second polarizer 33 is polarized in a direction perpendicular to the optical axis of the first polarizer 31 . The ordinary and extraordinary rays from the second polarizer 33 have swapped places incident upon the first polarizer 31 , because of this exchange, the light, having passed through the first polarizer 31 , does not leave the first polarizer 31 in parallel rays. The non-parallel light is focused by the molded lens 11 at a point which is not located at the end of the optical fiber 13 . Thus light in the reverse direction is not passed back into the optical fiber 13 of the input port 10 .
A mounting tube 40 has a chamber (not labeled) for accommodating and fixing the input and output ports 10 , 20 and the optical isolating means 30 . Soldering holes 401 are defined between an outside surface (not labeled) of the mounting tube 40 and the chamber (not labeled) of the mounting tube 40 , for soldering the input port 10 , the output port 20 , and the isolating means 30 to an inside of the mounting tube 40 .
It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
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An optical isolator ( 100 ) includes an input port ( 10 ), an output port ( 20 ), an optical isolating means ( 30 ) and a mounting tube ( 40 ). The input port includes an optical fiber ( 13 ) having an exposed end, a ferrule ( 12 ) defining a through hole 121 for holding the optical fiber, a molded lens ( 11 ), a sleeve ( 14 ) and a metal holder ( 15 ). The molded lens collimates optical signals transmitted from the optical fiber. The output port is constructed like the input port. The optical isolating means is disposed in an optical path between the input port and the output port. The optical isolating means transmits optical signals in an input direction and blocks reflected optical signals in the reverse direction. The mounting tube accommodates and fixes the input and output ports and the optical isolating means.
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FIELD OF THE INVENTION
[0001] The present invention lies in the field of gymnastic exercise apparatus, and relates to an exercise stick for athletes such as walkers, roller skaters or on-road cross-country skiers, according to the introductory part of the first patent claim.
BACKGROUND OF THE INVENTION
[0002] The recent type of sport called “Nordic walking” was initially developed as a summer training method for top athletes in the field of marathon, biathlon and Nordic combination. Its popularity has increased greatly in the last years. Today, Nordic walking is performed by a broad public spectrum as an all-season fitness sport. Nordic walking is however not only suitable for fitness exercise, but also for rehabilitation after injuries, operations or disease.
[0003] Nordic walking is a walking or running with the application of special sticks, which are held in each hand of the athlete. Accordingly, the technique of Nordic walking is equivalent to the execution of movement during cross-country skiing. Nordic walking encourages the physiological, diagonal course of movement on walking, by way of the conscious use of the sticks. One advantage compared to conventional walking or running lies in the fact that the muscle system of the arm and of the upper part of the body are also exercised. Furthermore, the body consumes more energy than with conventional walking or running at the same speed.
[0004] The sticks which have been used for Nordic walking up to now are typically manufactured of carbon- and glass fibers (30% carbon composite pole) which ensures a low intrinsic weight, an extreme load capability and a long life duration. In contrast to sticks with a metal core, no disturbing and burdening vibrations are transmitted onto the wrist joints, elbow joints and shoulder joints with the application of such sticks. The optimal stick length is 70% of the body size. Specially designed hand loops at the upper stick end ensure a strain-free application of the sticks over longer periods of exercise. The lower end of the stick should permit a push-off. The lower end of the sticks may be selectively provided with a rubber cushion—for smooth ground such as roads, asphalt, stone—or with a metal tip—for wooded ground and fields, in order to take into account the varying nature of the ground.
[0005] Despite the above-described equipping possibilities for the lower end of the stick, known Nordic walking sticks still have the disadvantage that they slip on the ground and render a push-off impossible. This is particularly the case with hard, smooth ground. The slipping of the sticks disturbs the walking rhythm.
SUMMARY OF THE INVENTION
[0006] It is therefore the object of the invention to further develop the known Nordic walking sticks to the extent that they permit an efficient push-off, and a rhythmic, flowing walking or running on any ground.
[0007] The object is achieved by the stick according to the invention, as is defined in patent claim 1 . Advantageous embodiments are specified in the dependent claims.
[0008] The known Nordic walking sticks are finally always directed to the winter sport of cross country skiing, with which the stick is periodically carried over the snow and inserted into the snow. The invention departs from this traditional cross country stick in a radical way and manner. It is based on the idea of providing the lower stick end with one or more wheels. Thus the exercise stick according to the invention may remain in constant contact with the ground. It is no longer necessary to lift it and insert it into the ground with each step. The path of the lower end of the stick is practically a pure translation instead of an up and down hopping movement, as is typical for known sticks. In order to permit a push-off, at least one wheel on the exercise stick according to the invention is provided with a reverse movement block—or with a coupling connected to direction or with a freewheel, which permits a rotation of the wheel in the forwards direction, but blocks it in the reverse direction.
[0009] Accordingly, the exercise stick according to the invention, for athletes, such as walkers, roller skaters or on-road cross country skiers, who travel in the running direction on the ground, comprises an elongate stick body. At least one wheel is attached at one end of the stick body, which permits a directed rolling travel of the exercise stick on the ground. At least one wheel is provided with a reverse movement block which permits a rotation of the wheel in the running direction, but blocks it in the opposite running direction.
[0010] The term “wheel” in this document is to be understood as any means permitting a directed rolling travel. Any forms of disks, rolling parts or rollers are included in this term.
[0011] A slipping-away of the exercise stick to the rear on pushing-off is to be avoided. For this purpose, it is particularly advantageous on the one hand to give the lower end of the stick a certain weight, and on the other hand to design the running surface of the wheels in a manner such that their static friction coefficient with respect to different conceivable ground is as high as possible. By way of this, an as large as possible static friction force is ensured between the wheel and the ground, which as is known, is a product of the normal force and the static friction coefficient.
[0012] The invention revolutionizes Nordic walking by way of making it more effective and at the same time gentler. The course of the movement of the athlete is smoother and more flowing thanks to the exercise stick according to the invention. The exercise effect may be increased or dosed by way of attaching additional weights on the sticks and/or the arms. In contrast to conventional sticks, such additional weights, although resulting in a higher energy consumption, only lead to a small increase in the loading of the joints, since indeed the weight is partly carried by the wheels. The danger of injury for following walkers or runners, which exist with the conventional stick due to the tip of the stick, is eliminated with the stick according to the invention. The constant ground contact gives the athlete increased safety. All these advantages, but in particular the last mentioned one, are of particular value if the exercise stick according to the invention is used for rehabilitation.
[0013] The invention in this document is discussed mainly on account of the application example of Nordic walking. But of course the exercise stick according to the invention may also be applied to other summer sports, such as for skating or on-road cross-country skiing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Preferred embodiment examples of the invention are described in a detailed manner by way of the drawings. Thereby, there are shown in:
[0015] FIG. 1 ( a ) an upper part, and ( b ) a lower part of the exercise stick according to the invention, in perspective views,
[0016] FIG. 2 various arrangements of wheels with the exercise stick according to the invention, in schematic perspective views,
[0017] FIG. 3 a cross section through a reverse movement block on the exercise stick according to the invention, (a) in the freewheel condition as well as (b) in the blocking condition, and
[0018] FIG. 4 a lower part of a further embodiment of the exercise stick according to the invention.
DETAILED DESCRIPTION
[0019] One embodiment of the exercise stick 1 according to the invention is represented in perspective views in FIG. 1 , wherein FIG. 1 ( a ) shows an upper part and FIG. 1 ( b ) a lower part of the exercise stick 1 . An actual stick body 2 is preferably composed of several, e.g. three segments 21 to 23 which in each case mutually engage in a telescopic manner, in order to permit a length adjustment. The mutual position of the segments 21 to 23 may be fixed in a stepless manner by way of locking rings 24 , 25 provided with threads. Alternatively, the exercise stick 1 may also comprise other means for the length adjustment and for fixation, such as is known from the state of the art. The stick body 2 could e.g. be composed of two segments and be provided with a collapsing mechanism which permits the two segments to be folded and thus the reduction of the length of the exercise stick 1 . In the condition of use, the two segments are connected to one another in a rigid but releasable manner by way of suitable locking means.
[0020] The stick body 2 may be manufactured from carbon- and glass fibers as is described for the state of the art. Other less expensive materials such as metal, wood, bamboo or plastic are however also possible. In contrast to the state of the art, the exercise stick 1 according to the invention is not restricted to a low intrinsic weight, and the load capability and absence of vibration are of secondary importance thanks to the invention, since the course of movement is smoother and more flowing with the exercise stick according to the invention.
[0021] The upper stick end 11 is equipped with a hand grip 3 and with a hand loop 31 , as are known from the state of the art. Lesser demands with regard to ergonomy and quality are placed on the exercise stick 1 according to the invention, than with sticks according to the state of the art, since the exercise stick 1 according to the invention is merely pulled along the ground, and not lifted or inserted.
[0022] The lower stick end 12 in the embodiment example of FIG. 1 is provided with two wheels 41 , 42 which on both sides of the stick body 2 are arranged on a common axle 5 . The axle 5 is rotatably mounted in a bearing 6 , and can be rotated in the running direction L Details with regard to this will be dealt with by way of FIGS. 3 ( a ) and 3 ( b ). The bearing 6 is rigidly connected to the stick body 2 , for example by way of an adapter element 7 . The adapter element 7 is preferably designed such that it may be mounted onto various types of already existing stick bodies 2 available on the market. Thus older sticks may be converted into sticks 1 according to the invention within the context of an add-on solution or retrofit solution, by way of separating the lower stick end ending at the tip, and attaching the adapter element 7 with the bearing 6 and wheels 41 , 42 instead. Of course independent solutions are also possible, in which the bearing 6 is fastened on the stick body 2 or integrated into it, in a direct manner, without the aid of an adapter element. In an alternative embodiment, the axle 5 may be fastened rigidly in the adapter element 7 , whilst the two wheels 41 , 42 are each unidirectionally rotatably mounted on the axle by way of a bearing.
[0023] The lower stick end 12 , including the wheels 41 , 42 , axle 5 , bearing 6 and adapter element 7 , is preferably provided with a larger intrinsic weight than the lower stick ends of conventional sticks. This increases the normal force F N which the exercise stick 1 exerts on the ground, and contributes to a good ground adherence of the wheels 41 , 42 . The intrinsic weight of the lower stick end 12 may for example lie in the range between 5 N and 100 N, and preferably between 7 N and 50 N.
[0024] The running surfaces of the wheels 41 , 42 are preferably manufactured of a material which has an as high as possible static friction coefficient μ o with respect to the conceivable ground, such as asphalt, stone, gravel, earth, grass, sand etc. This in turn increases the ground adherence and permits a slip-free push-off of the exercise stick 1 . The static friction coefficient μ o with regard to dry asphalt should be larger than 0.4 and preferably larger than 0.5, for a dry earth path should be larger than 0.3 and preferably larger than 0.4. An ideal material for the running surface appears to be rubber. The wheels 41 , 42 may for example be designed as solid rubber wheels. The running surface may have a profile or be without any profile.
[0025] The static friction coefficient F R , as is known, is given by
F R =μ 0 ·F N .
[0026] On dry asphalt, with the values for the normal force F N and static friction coefficient μ o specified above, static friction forces F R which lie between 3.5 N and 25 N or greater result merely on account of the intrinsic weight of the lower stick end 12 . Added to this is always a perpendicular component of the compressive force F D (cf. FIG. 3 ( b )) with which the athlete pushes away on the exercise stick 1 and which increases the normal force F N and thus also the static friction force F R . The static friction force F R may be increased yet even more significantly with heavy lower stick ends 12 and additional weights (cf. FIG. 4 ). The ground adherence may also be improved by way of providing the running surfaces of the wheels 41 , 42 with suitable profiles, as is known for example for motor car technology.
[0027] The wheel diameter d, the track width w and the number of wheels 41 , 42 may be very different. It is possible to adapt these parameters to the envisaged type of application with exercise sticks 1 according to the invention. For main use on an asphalted road, one would then select smaller wheels 41 , 42 with a narrower track width w, whereas somewhat larger wheels 41 , 42 with a broader track width w are suitable for uneven, wooded ground. The wheel diameters d may e.g. lie in the range between 4 cm and 20 cm, and preferably between 6 cm and 10 cm. Exemplary track widths w may be selected in the region between 3 cm and 30 cm, and preferably between 5 cm and 15 cm.
[0028] The number and arrangement of the wheels with the exercise stick 1 according to the invention is discussed by way of the embodiment which is schematically illustrated in FIG. 2 . The exercise stick 1 may be equipped with a single wheel or with several, for example up to eight wheels. An exercise stick 1 with a single wheel 41 such as is shown in FIG. 2 ( a ) has the advantage of a great simplicity and low cost, whereas it provides no lateral stability. Two wheels 41 , 42 arranged laterally next to one another, as is shown in FIG. 2 ( b ) or also in FIG. 1 , stabilize the exercise stick against lateral tilting. In the embodiment example of FIG. 2 ( c ), four wheels 41 to 44 are arranged behind one another in the running direction L, as it is known from the newer roller skates known as inline skates. FIGS. 2 ( d ) and 2 ( e ) show combinations of wheels 41 to 43 and 41 to 44 which are arranged next to one another and behind one another, respectively. Of course the exercise stick 1 according to the invention may also have more than four wheels, e.g. up to eight wheels.
[0029] The stick body 2 should be pivotable in the plane which is perpendicular to the ground and contains the running direction L. The pivotability is inherently present in the embodiment examples of FIGS. 2 ( a ) and ( b ). A particular mounting 51 for the stick body 2 should be provided on a wheel mounting frame 50 in the embodiment examples of FIGS. 2 ( c ) to 2 ( e ), which permits this pivotability. The man skilled in the art is capable of designing suitable mountings 51 with the knowledge of the invention.
[0030] A reverse movement block 8 which is important to the exercise stick 1 according to the invention is explained with the aid of FIG. 3 . In the embodiment example of FIG. 1 , the reverse movement block 8 is installed in the bearing 6 , and acts on the common axle 5 of the two wheels 41 , 42 rigidly connected to the axle 5 . Alternatively, the axle 5 may also be rigid and the reverse movement block 8 may be attached between the axle 5 and the wheel 41 or 42 . The embodiment example which has been chosen here is a grip roller freewheel which is known per se. The axle 5 is rigidly connected to an inner race 81 , whilst a bearing case 61 is rigidly connected to a roller guide ring 83 . The clamping rollers 82 are located between the inner race 81 and the bearing case 61 , embedded in corresponding recesses in the roller guide ring 83 .
[0031] If the athlete exerts a tensile force F Z with a non-zero component in the running direction L onto the stick body 2 or the adapter element 7 , as shown in FIG. 3 ( a ), then the clamping rollers 82 are located in a position which permits an unhindered rotation of the axle 5 with respect to the bearing case 61 . The wheels 41 , 42 , pulled by the athlete, run forwards on the ground 9 in the running direction L.
[0032] If however the athlete pushes away the exercise stick 1 and thus exerts a compression force F D with a non-zero component opposite to the running direction L, onto the stick body 2 or the adapter element 7 , as represented in FIG. 3 ( b ), then the clamping rollers 82 are pressed into wedge-like pockets. In this position, a rotation of the axle 5 with respect to the bearing case 61 is prevented on account of the frictional contact. Thus a reverse rotation of the wheels 41 , 42 is impossible and the athlete may push off to the front in the running direction L.
[0033] Other reverse movement blocks 8 are also possible, which are known per se, and when required may be adapted to the exercise stick 1 according to the invention by the man skilled in the art. Here a ratchet-type freewheel (with pawl and ratchet), grip freewheel, sprag freewheel, friction freewheel or the tooth freewheel are to be mentioned as further examples of suitable reverse movement blocks.
[0034] The embodiment of FIG. 4 permits a reversible fastening of additional weights 71 . 1 to 71 . 4 on the lower stick end 12 . The additional weights 71 . 1 to 71 . 4 may e.g. be designed as metal disks, but other forms such as rings or balls are also possible. Each metal disk 71 . 1 to 71 . 4 is provided with a through-opening whose inner shape corresponds to the outer shape of the adapter element 7 , so that they may be attached onto the adapter element 7 . The through-bore may, but need not necessarily be located in the middle of the respective metal disk 71 . 1 to 71 . 4 . In the embodiment example of FIG. 4 , the through-opening is attached acentrically in an edge region of the metal disk 71 . 1 to 71 . 4 . This has the advantage that in the running position—in which the stick body 2 is not perpendicular to the ground, but is inclined to the front (in the running direction L or in the direction of the static friction force F R )—the center of gravity of the additional weights 71 . 1 to 71 . 4 and thus also of the lower stick end 12 lies as low as possible. Thus the wheels 41 , 42 acquire optimal ground contact as quickly as possible again given unevenness of the ground. A rail 72 or other guide- and fixation means may be provided at the lower stick end 12 or on the adapter element 7 , for the improved guidance on assembly and for the improved fixation of the additional weights 71 . 1 to 71 . 4 . Furthermore fastening means (not shown) for the reversible fastening of the additional weights 71 . 1 to 71 . 4 may be present at the lower stick end 12 or on the adapter element 7 .
[0035] An additional weight 71 . 1 to 71 . 4 may weigh e.g. between 5 N and 20 N or 10 N. The number of additional weights 71 . 1 to 71 . 4 or their total weight may be selected according to the requirement and the performance of the athlete. A total weight of the lower stick end 12 of up to 200 N is indeed realistic. On the one hand the normal force F N is increased, and thus the static friction force F R is further increased with such additional weights 71 . 1 - 71 . 4 . On the other hand, the additional weights 71 . 1 to 71 . 4 permit the exercise effect to be increased or to be dosed in an individual manner. This permits new exercise possibilities which are excluded with conventional sticks. Conventional sticks are constructed in an as lightweight as possible manner in order not to overload the wrist joints of the athlete.
LIST OF REFERENCE NUMERALS
[0000]
1 exercise stick
11 upper end of the exercise stick
12 lower end of the exercise stick
2 stick body
21 - 23 segments of the stick body
24 , 25 locking rings
3 hand grip
31 carrier loop
41 , 42 , 43 , 44 wheels
5 axle
50 wheel mounting frame
51 mounting for stick body
6 bearing
61 bearing case
7 adapter element
71 . 1 , 71 . 2 , 71 . 3 , 71 . 4 additional weights
72 rail
8 reverse movement block
81 inner race
82 clamping rollers
83 roller guide ring
9 ground
d wheel diameter
F D compressive force
F N normal force
F R static friction force
F Z tensile force
L running direction
w track width
μ o static friction coefficient
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Disclosed is an exercise pole ( 1 ) designed for athletes such as walkers, roller skaters, or on-road cross-country skiers. Said exercise pole ( 1 ) comprises an elongate pole body ( 2 ), at one end ( 12 ) of which two wheels ( 41, 42 ) are mounted that allow the exercise pole ( 1 ) to be moved in a directed rolling manner. The wheels ( 41, 42 ) are equipped with a return stop ( 8 ) that allows the wheel ( 41, 42 ) to be rotated in the direction of travel (L) while blocking the same counter to the direction of travel (L) such that pushing off in a forward direction is made possible. The fact that the inventive exercise pole ( 1 ) is in permanent contact with the ground allows the athlete to make smoother and more flowing movements while providing him or her with a greater sense of safety.
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FIELD OF THE INVENTION
This invention relates generally to medical diagnostic apparatus and more particularly to a device for accelerating the protein concentration of body fluids and removal of samples therefrom for further tests.
BACKGROUND OF THE INVENTION
The particular proteins and the concentration thereof in body fluids such as ascites fluid, spinal fluid and urine, may indicate a particular pathological condition. For diagnostic purposes, it is desirable to separate the proteins from the fluids to some extent, that is, to obtain a fluid having a substantially higher concentration of the proteins, to facilitate subsequent analysis through procedures such as electrophoresis and gel chromatography. Collodion bags have previously been used for dialyzing the body fluid to obtain the desired concentration but as the amount of the fluid in the bag is reduced during the dialysis procedure, the bag surface area in contact with the fluid decreases. This results in a reduction of the speed of dialysis and reduced efficiency of the bag membrane. Furthermore, presently available means for removal of samples of the concentrated fluid from the collodion bag have certain drawbacks, among which are: the need for a separate pipetting or fluid withdrawal system; the use of narrow bore pipette tips can damage the collodion bag; a potential hazard to the operator if mouth pipetting is employed, a common laboratory practice. Additionally, Pasteur pipettes which are normally employed for such purposes are fragile and can easily be broken off in the apparatus.
For reference purposes, collodion bags are small porosity membranes formed to separate out proteins of different molecular sizes from the fluids in which they reside. Collodion bags may be used to separate out molecules having a size down to as low as 10,000 molecular weight. The bag itself is formed of cellulose nitrate which forms the membrane, the substance of the membrane generally being referred to by the term collodion. The membrane is, in effect, a fine orifice lattice structure used for mechanical filtration of molecules from fluids in which the molecules are carried or suspended.
SUMMARY OF THE INVENTION
Broadly speaking, this invention is concerned with a collodion bag ultrafiltration concentrator having means for increasing the amount of surface area contact of small liquid samples with the membrane surface of the collodion bag thus accelerating the dialysis action or rate of diffusion through the bag wall, and means to facilitate taking samples of the concentrated fluid from within the bag at any time. Specifically, the invention comprises a displacement body which occupies a significant portion of the interior volume of the bag. The displacement body is so formed as to permit the fluid being dialyzed in the bag to remain in contact with substantially the entire inner surface of the bag until only a very small concentrated amount of the fluid remains in the bag. By maintaining the fluid in contact with a relatively large portion of the bag surface, the speed of dialysis is significantly increased. A rigid steel tube extends through the longitudinal axis of the body and is used both for inserting further samples of fluid and for removing samples to determine the concentration of the fluid in the bag.
The apparatus includes further structure for facilitating the application of larger fluid samples to the collodion bag and removal of samples of concentrated fluid therefrom for further testing. Such structure includes a syringe coupled to the tube, and a syphon setup to accommodate relatively large volume samples. Such large samples may be necessary where the concentration of the substance to be tested is quite low.
BRIEF DESCRIPTION OF THE DRAWING
The objects, features and advantages of this invention will be readily appreciated from the following detailed description when taken in conjunction with the accompanying drawing in which:
FIG. 1 is a partially broken away sectional view of the ultrafiltration apparatus of this invention;
FIG. 2 is an exploded view of the apparatus of the invention shown in FIG. 1;
FIG. 3 is an enlarged perspective view of the displacement body of the invention; and
FIG. 4 is an end view of the displacement body of FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawing, and more particularly to FIGS. 1 and 2 thereof, there is shown a container 11 having a side arm male connector 12 attached to the neck 13 thereof, and a top opening 14. Positioned in opening 14 is a stopper 15 having an axial bore 16 therethrough, in which resides cylindrical outer sleeve 17. The sleeve is formed with a slightly tapered female fitting 20 inside end 21 and an open upper end 22. Within sleeve 17 is inner sleeve 23 having a male fitting 24 at one end adapted to mate with the female fitting of sleeve 17. Mounted on end 24 of sleeve 23 is collodion bag 25 having a closed end 26 and an open end 27, the material of the bag in the vicinity of the open end being sandwiched between the male and female ends of sleeves 23 and 17 respectively. Disposed within bag 25 is displacement body 31 attached to the end of a substantially rigid hollow tube 32, the tube having a fitting 33 at the upper end thereof. Fittings 20 and 24 are shown as matching frusto-conical elements but other shapes may be used to accomplish the purpose.
Collodion bag 25 has a nominal capacity of approximately 8 ml but displacement body 31 occupies a substantial portion of the interior volume of the bag, preferably about 6 ml of that volume. A sample of the fluid to be diagnosed may range in volume typically from 2 to 10 ml. With displacement body 31 residing within collodion bag 25, as little as 2 ml of fluid will substantially fill the space between body 31 and the interior dialyzing surface of the bag, any remaining sample being displaced within inner sleeve 23 at the beginning of the procedure. Thus, whether 2 or 10 ml are initially used, and when the total amount of fluid remaining to be dialyzed through the dialyzing surface of the bag is reduced to as little as 2 ml, the bag effectively remains substantially full and the fluid is in contact with most of the inner surface area thereof. This substantially improves the speed and efficiency of the operation of the collodion bag throughout the dialyzing procedure as fluid passes through the surface of the bag into container 11 leaving increased concentration of macromolecular materials such as proteins within the bag itself.
With reference now to FIG. 3, the tapered displacement body is shown having two diametrically opposed surface grooves 34 which meet at tip 35 forming a diametrical groove 36 across the tip. The displacement body is formed around the distal end of tube 32, the tube normally extending to the end 35 of the body. When the grooves 34 and 36 are milled or machined, the end of tube 32 is likewise machined to define part of diametrical groove 36. Groove 34 has a depth of approximately 1.5 mm at tip 35 and tapers to a depth of 0 mm at point 37. The end 37 of groove 34 substantially corresponds to a transition between portion 38 of maximum taper of the displacement body, and upper body portion 41 of lesser taper. For reference purposes, the displacement body is formed of inert plastic material, preferably polypropylene which can be made relatively hard and can be machined. As an example, with an 8 ml bag 25, body 31 will be approximately 80 mm long to the point 42 where it tapers smoothly to the surface of tube 32, and the slots 34 extend approximately 25 mm up the side of the body from the narrowly rounded tip. Although two grooves 34 have been found to be sufficient, more than two may be used if desired.
As shown in FIG. 1, tip 35 rests on the inside bottom 26 of bag 25 and the sides of the bag fit loosely around the surface of body 31. Because of the pressure exerted by the fluid in the bag, a slight separation between the interior surface of the bag and the surface of the body will normally be maintained during dialysis. Slots 34 and 36 permit ready access of the fluid to the interior bore of body 31 whether the fluid is applied through tube 32 into the bag or withdrawn from the bag through the tube. When fluid is withdrawn for test purposes to determine the concentration of the fluid in the bag, the fluid is allowed to run down to the tip of body 31 through slots 34 even if the surface of the bag should happen to contact the lower portion of the body in the general vicinity of the slots.
In order to facilitate diffusion of liquid through the wall of bag 25, a vacuum means (not shown) may be coupled to male fitting 12 on the neck of the container. Due to the pressure differential of the fluid in the collodion bag and the atmosphere in the container surrounding the bag, fluid is encouraged to diffuse more rapidly through the wall of the bag.
Fitting 33 at the top of tube 32 may be of any desirable type such as those known and sold under the trademark Luer-Lok. In order to withdraw a sample from bag 25, a syringe 43 is attached to fitting 33 and the piston of the syringe is withdrawn creating a partial vacuum in tube 32 thereby drawing fluid from bag 25 up into the barrel of the syringe. When a desired amount of the concentrated fluid sample is drawn into the syringe, the syringe is disconnected from fitting 33 and the fluid may then be taken to another location for further testing.
If it is desired to expand the sample capacity of the dialysis apparatus shown in FIG. 1, the capacity of the bag and upper tube together being approximately 24 ml, a three-way valve 44 (FIG. 2) is attached to fitting 33. Fitting 45 is connected to syringe 43 and connector 46 is coupled to a flexible tube 47 which leads to an exterior reservoir 48 of the fluid being tested. This sets up a siphoning arrangement which is started by connecting the syringe to the reservoir through the valve so that a portion of the sample can be withdrawn from the reservoir into the barrel of the syringe. The valve is then closed to the reservoir and opened to tube 32 so that the fluid may be injected into bag 25 and sleeve 23. Thereupon the valve is closed to the syringe and opened between the reservoir and tube 32, thus establishing a continuous fluid connection between the reservoir and the collodion bag. By maintaining the collodion bag below the level of the fluid reservoir, a siphon arrangement is maintained and continuous dialysis through the wall of the collodion bag is achieved. In this particular arrangement, the displacement body is not initially needed to facilitate speed of dialysis of the fluid in the bag but it provides the necessary apparatus to permit easy withdrawal of samples from the bag for testing purposes.
It may be noted that if the displacement body were not attached to the end of tube 32, insertion of the tube to withdraw a sample could very easily puncture the collodion bag and ruin the entire procedure. Thus it is apparent that body 31 enhances the speed and efficiency of dialysis in the collodion bag as well as facilitating removal of samples of the concentrated fluid from the bag.
By way of example and without limiting the structure to certain materials, container 11 and sleeves 17 and 23 are normally made of glass while tube 32 is normally made of stainless steel. Other appropriate inert substances could be used as desired.
In view of the above description, it is likely that modifications and improvements will occur to those skilled in the art which are within the scope of this invention.
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Ultrafiltration apparatus employing collodion bag dialyzing means. This apparatus provides a means for accelerating the dialysis process and a cooperative means for obtaining samples of the concentrate from the collodion bag. A displacement body with an axial bore is attached to a tube and positioned within the collodion bag. By displacing fluid volume in the bag, the speed of dialysis is increased. The combination of the tube and displacement body also facilitates removal of samples of the concentrated fluid from the bag.
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The present invention is related generally to the method of synthesizing polymeric ketones. More particularly, the present invention is related to producing novel monomers for the synthesis of new as well as known polymeric ketones. The polymers produced in accordance with the present invention are initially non-crystalline and soluble in ordinary organic media, thereby allowing easy processibility without the use of exotic solvents and high temperatures in order to obtain desirable crystalline end products.
Polymeric ketones are a relatively rare class of materials useful in a number of high performance applications. 1 It should be mentioned, however, that whereas the ketone functionality bestows highly desirable crystalline structure to the polymers, it is also this crystallinity which makes the processing of the polymers a difficult problem, thus limiting the usefulness of these materials.
Heretofore, aromatic polymeric ketones have been made by Friedel-Crafts reactions, 2 ring opening reactions 3 or by nucleophilic substitution, 2 the latter being commonly used in commercial preparations, or coupling of aromatic dihalides. 4 However, it should be noted that nucleophilic substitution does not allow for easy processability 2 ,5-9 of crystalline polymers and the Friedel-Crafts methodology is quite expensive because of the handling and disposal of large quantities of strong Lewis or Bronstead acids required to maintain solubility of the polyketone. 2 ,10-12
Aliphatic polyketones have been made by copolymerization of olefins and CO by both free radical and palladium catalyzed "insertion" polymerizations. 13 A maximum of 50 mole percent CO may be incorporated by these methods. 13
Thus, it is clear that the currently available synthetic techniques have limited scope and applicability.
SUMMARY OF INVENTION
It is, therefore, an object of the present invention to provide more economical and efficient synthetic methodologies than presently available for the preparation of polymeric ketones.
It is another object of the present invention to provide novel monomers for the synthesis of new and known polymeric ketones.
A further object of the present invention is to provide non-crystalline, easily processable precursor or intermediate polymers which are readily convertible to desired crystalline polyketone materials, for example by acid hydrolysis.
It is an additional object of the present invention to provide novel polyketones with aromatic, aliphatic or mixed aromatic/aliphatic backbones.
Other objects and advantages will become evident from the following detailed description of the invention.
BRIEF DESCRIPTION OF DRAWINGS
The foregoing and other objects, features and many of the attendant advantages of the invention will be better understood upon a reading of the following detailed description when considered in connection with the accompanying drawings, wherein:
FIG. 1 shows the generic classes of monomers and polymers that may be formulated in accordance with the present invention. The letter E represents any electrophile and X and Y are aliphatic, aromatic or mixed aliphatic/aromatic;
FIGS. 2-6 show the formulae of various reactants and products described in the present application;
FIG. 7 shows representative structures of possible arylene groups in the monomers (e.g. in 12) and derivative polymers (e.g. 14, 15, 17, 18, 22, 26, 30, 31, 33, and 34), in accordance with the present invention;
FIG. 8 shows representative examples of various R groups in 12, 27, and 35, and derivative polymers (e.g., 14, 17, 25, 28, 30, 33, 36, and 38).
FIG. 9 shows representative examples of suitable divinyl compounds 32.
DETAILED DESCRIPTION OF THE INVENTION
The above and various other objects and features of the present invention are achieved by employing α-aminonitriles as monomers for the synthesis of high molecular weight aromatic, aliphatic or mixed aromatic/aliphatic polyketones. Polymerization of α-aminonitriles has the particular advantage of producing a soluble precursor polymer retaining the aminonitrile functionality. Acid hydrolysis then yields the desired crystalline polyketone.
As noted in the literature 7 ,14, the extents of crystallinity and melting points of poly(arylene-ether-ketones) are a function of the proportions of ether and ketone functions in the backbone. And inclusions of more flexible backbone functionalities, such as alkylene or sulfone lead to a loss of crystallinity. 2 By use of aminonitrile chemistry, it is possible to include these functionalities in any desired proportions.
Among other advantages, the methodology of the present invention allows synthesis of macromolecules whose backbones consist exclusively of arylene and carbonyl moieties. Additionally, new types of polyketones, for example those containing α-diketo moieties, are also produced by employing the methodology described herein. Furthermore, by applying this methodology to aliphatic systems, new classes of polymers such as homologs of olefin/carbon monoxide copolymers are also obtained. These new macromolecules are valuable for their crystallinity and associated mechanical performance and photodegradability.
A unique feature of the methodology of the present invention is that the polymerization produces the carbonyl moieties in a protected or masked state, causing the polymers to be amorphous and soluble, allowing high molecular weights to be achieved without exotic solvents and high temperature treatment. Then, by merely deprotecting the carbonyl moieties by conventional methods, e.g. by mild acid treatment, crystalline polymeric or copolymeric macromolecular materials having ketone functionality are obtained in the final processing step.
It is understood that unless mentioned otherwise all scientific and technical terms have the same meaning as understood by one of ordinary skill in the art. Except as described herein all methods used or contemplated herein are standard or conventional methodologies well known to a skilled artisan in the art to which this invention belongs. All references mentioned hereunder are hereby incorporated herein by reference.
As used herein, the term "soluble polymers" is defined as the polymers soluble in those commonly and ordinarily used, low boiling point, organic solvents, e.g. chloroform, toluene, benzene and the like, in which the important polyketones of the prior art, such as poly-ether-ether-ketone are insoluble. Depending on the structure, the polymers of the present invention may or may not be water soluble.
It is noted that the underlined Arabic numerals refer to the corresponding structural formula and the superscipt Arabic numerals refer to particular references listed at the end of the specification.
MATERIALS AND METHODS
Unless mentioned otherwise, the general reaction conditions are as follows.
(a) Polymerization:
Bases: NaOH, n-BuLi, NaH, LDA (lithium diisopropylamide), and the like.
Solvents: dimethylformamide (DMF); dimethylacetamide(DMAC); N-methylpyrollidinone (NMP); dimethyl sulfoxide (DMSO); tetrahydrofuran (THF); ether; water/toluene two phase system (for NaOH); and the like.
Temperature: -78 to 250 C.
(b) Deprotection:
Acids: Organic acids, such as acetic, oxalic, p-toluenesulfonic, trifluoroacetic; trifluoro-methanesulfonic; or mineral acids.
Solvents: organic acid, water, water/THF, water/dioxane, or one of the above-mentioned solvents by quenching into the acidic medium.
Temperature: 25-150 C.
Preparation
α-Aminonitriles (1) are readily prepared in high yields from aldehydes and secondary amines, for example by Strecker reaction 15 ,16. ##STR1##
Depending on the nature of R, a variety of bases may be employed to abstract the acidic proton; for aryl derivatives NaOH, NaH, etc. may be used, while stronger bases (BuLi, LDA, etc.) are employed when R=alkyl. 16 Alkylation, Michael reactions and other nucleophilic displacement reactions may also be carried out with these anions. These are standard reaction mechanisms well known to skilled artisan. 16 ,17
The α-aminonitrile 2 (Ar=phenyl unless noted) derived from benzaldehyde and morpholine is used herein to illustrate these transformations. Typically the reactions discussed are carried out under very mild thermal conditions at 0°-30° C. (or below where noted) in DMF using NaH as base to form the carbanion 3. Alkylation of 3 with ethyl bromoacetate (-60 to -70 C.) yields 4c. 17 Methyl iodide and 3 produce 5a via 4a in 96% overall yield, 18 while 5b results in 94% overall yield from isopropyl bromide. 18 Reaction of 3, Ar=p-anisyl with acrylonitrile produces 6 a quantitatively. 17 Likewise methyl methacrylate and methyl crotonate produce 6b and 6c in 96 and 98% yields, respectively. 16 Acidic hydrolysis of 6a and 6b led to ketones 7a and 7b in 94 and 95% yields, respectively. 17
Reaction of acyl anion equivalent 3 with activated aromatic halides is exemplified by formation of 8a by reaction with p-fluoronitrobenzene; hydrolysis (acetic acid) gave 4-nitrobenzophenone (9a) in 89% overall yield. 17 Likewise p-cyanofluorobenzene produced 4-cyanobenzophenone (9b) in 88% overall yield via 8b and 2-nitro-4-trifluoromethylchlorobenzene afforded a 92% overall yield of 2-nitro-4trifluoromethylbenzophenone (9c) via 8c. 17
Carbanions 3 react with acid chlorides (-60° to -70° C.) to produce intermediates 10, which upon hydrolysis form α-diketones 11. In the case of ethyl chloroformate the yield of 10, R=OC 2 H 5 is 94%. 17
It should be noted that the use of acyl anion equivalents for polymerization in accordance with the requirements for step growth polymerizations must meet several criteria to produce high molecular weight products. Reactions must proceed to high conversion without side reactions. The high yields obtained for reactions of aminonitriles under unoptimized conditions are noteworthy in this regard. Premature precipitation must be avoided; since aminonitrile moieties are retained in the polymer, solubility is not a problem. The monomers must be difunctional, either of the AB or AA/BB type. The aminonitriles anions are reacted with electrophiles of the types such as alkyl halides, acid chlorides, activated aromatic halides and Michael acceptors. If E represents any of these electrophiles, a number of generic classes of new monomers and polymers may be formulated in accordance with equations 1 and 2 (EQ.1 and EQ.2) shown in FIG. 1.
A. AROMATIC POLYKETONES
Aromatic polyketones are products of either AA/BB (Eq.1) or AB (Eq.2) systems where X and Y are aromatic. For the first approach (AA/BB), reactions of bis(aminonitriles) derived from aromatic dialdehydes with either activated aromatics or acid chlorides are required.
New bis(aminonitrile)s 12 with difluorobenzophenone (13) produce the polyaroyls 15 via poly(aminonitrile ketone)s 14. These unique polymers (15) have the highest possible carbonyl content for such polymers and exhibit very high crystallinity and melting points. Hydrolysis by wet spinning of 14 through an acidic medium may be used to produce high performance fibers of 15.
Reaction of 12 and difluorodiphenylsulfone (16) produces the novel poly(sulfone ketone ketone) 18 via intermediate poly(aminonitrile sulfone) 17.
Extensions to the known activated aryl halides 19, 20 and 21 produce poly(ketone ketone ketone ketone)s 22 and 23 repectively, and poly(ether sulfone ketone ketone sulfone) ["PESKKS"] 24. Of course, copolymerizations are also possible.
Reactions of bisaminonitriles 12 with aromatic diacid chlorides produce the poly(α-diketones) or poly(benzil)s 26, via soluble intermediates 25. A variety of aromatic diacid chlorides are available, including terephthaloyl, isophthalolyl, oxydibenzoyl, and the like.
The arylene group (˜Ar) in monomer 12 and derivative polymers (e.g., 14, 15, 17, 18, 22-26) may vary widely. Representative structures of such arylene groups are shown in FIG. 7.
The R group of 12 may also be varied so as to influence solubility and reactivity. The R groups listed in FIG. 8 are exemplary.
AB monomer systems 27 can also be prepared from suitable substituted benzaldehydes, which in turn are available by acylation or sulfonylation of 4-biphenylcarboxaldehyde or p-phenoxybenzaldehyde. These aminonitriles are precursors to polyketones 29 via intermediate poly(aminonitriles) 28. 29a is a poly(ether ketone ketone), 29b a poly(ketone ketone), 29c a poly(ether ketone sulfone) and 29d a poly(ketone sulfone). Of course, other similar AB monomers are considered within the scope of this invention.
B. ALIPHATIC POLYKETONES
Polyketones with aliphatic backbone components may also be prepared via aminonitrile chemistry from AA/BB or AB monomer systems as summarized in Eqs. 1 and 2, where X and/or Y are aliphatic.
First, reactions of bis(aminonitriles) derived from aromatic dialdehydes with aliphatic dihalides are considered. For example 12 with α,w-dihaloalkanes will produce polyketones 31 via 30. In fact aliphatic spacers have only recently been incorporated into poly(ether ketone)s for the first time. This hitherto unknown series of polymers 19 have a combination of the properties of aromatic polyketones and ethylene/CO copolymers. Crystallinity is expected with melting points intermediate between the former (˜400° C.) 2 ,7 and the latter (110°-240° C.). 20 When y>2 enhanced photodegradability 13 is expected on the basis of increased UV absorbance brought about by the presence of the aromatic chromophore.
Michael reactions of 12 with suitable divinyl compounds 32 produce intermediate polymers 33 which are converted to poly(ketones) 34 by hydrolysis. Suitable examples of divinyl compounds 32 are shown in FIG. 9. Thus, the polymers 34 can be designed to be poly(keto ester)s, poly(keto amide)s, and the like.
Backbones consisting solely of alkylene and ketone moieties are synthesized from bis(aminonitriles) derived from aliphatic dialdehydes. Formation of the corresponding bis(aminonitriles) is straightforward. Although other aliphatic dialdehydes are included in the present disclosure, the most available dialdehyde is glutaraldehyde, leading to 35, X=3. Formation of the dianion of 35, X=3 followed by condensation with α,w-dihaloalkanes produces a family of poly(aminonitriles) 36 readily soluble and processable and easily converted under acid catalysis to aliphatic polyketones 37.
By variation of x and y in 37 a novel family of analogs of the ethylene/CO copolymers can be synthesized. In the case of 37 where x and y≦2, no γ-hydrogens are available for Norrish type II photodegradation and the polyketone will be stable and correspond to the next higher homolog of the alternating ethylene/CO copolymers, having three methylene groups between carbonyl pairs. For x or y>2 photodegradation is possible. 13
Use of bis(Michael acceptors) 32 in reacting with 35 via intermediates 38 produces the aliphatic polyketones 39, again with incorporation of ester, amide, etc., linkages. This allows combinations of the properties of polyketones with those of polyesters, polyamides, etc.
The molecular weights achievable in these step growth polymerizations are subject to the usual constraints: stoichiometric equivalence, monomer purity and absence of side reactions. However, unlike the ethylene/CO copolymers made by free radical methods, these condensation polymers are free of branching and, therefore, crystallizable. Of course, these reactions may also be extended to substituted dihaloalkanes.
AB monomers 40 may be derived, for example, from haloaldehydes. Polymerization of these in the presence of a base leads to polyketones 42 via soluble intermediate polyaminonitriles 41. Here again x, the number of methylene units, is variable, enabling control of physical properties (T g , T m , etc.) and photodegradability.
These aliphatic polyketones (e.g., 31, 37, and 42) constitute a unique set of polyketones in terms of the range of composition and structural regularity. Especially noteworthy are the cases in which x is an odd number; such polyketones cannot be made by the usual free radical or Pd catalyzed insertion polymerization methodologies.
In the case of aliphatic systems, linkages other than linear or branched alkylene, such as oxyalkylene, aminoalkylene or thioalkylene, are considered within the scope of X/Y variations of Eq.1 and Eq.2 noted supra.
C. AROMATIC AND ALIPHATIC POLYKETONES FROM FORMALDEHYDE AMINONITRILES
Use of the AA monomeric aminonitriles 43 derived from formaldehyde enables synthesis of both aromatic and aliphatic and mixed aromatic/aliphatic polyketones. The aminonitrile functions as a carbonyl equivalent. 21 For example, reaction of 43 via its anion with 13 produces soluble 44 which can be converted to polyaroyl 45. Similarly, from 43 and 16, 47 results by way of soluble precursor 46. Reactions of 43 with bis(Michael acceptors) 32 lead to soluble precursor 48, which upon hydrolysis produces 49. Aliphatic polyketones 51 result via soluble precursor polymers 50 from reaction of dihaloalkanes with the anion of 43.
All of the advantages mentioned above, notably those of the control of the carbonyl content, T g , T m , molecular structure and photodegradability, accrue to the use of 43 in synthesis of polyketones.
EXAMPLE 1
α-(N-morpholino)benzyl cyanide (2,Ar=C 6 H 5 )
NaHSO 3 , 10.5 g (100 mmol), was dissolved in 150 mL of water and 11 mL (100 mmol ) of benzaldehyde were added and the mixture was stirred for 2 h until homogeneous. 8.7 mL (100 mmol) of morpholine were added in one aliquot and the stirring was continued for two more h. Finally, 5 g (100 mmol) of NaCN were added and the solution was stirred for 6 h at the end of which a shiny, white solid material precipitated out. The yield was 19.8 g (98%), mp=66.8°-67.8° C. It was recrystallized from 150 mL (1:1) hexane : EtOAc to yield shiny, white platelets, mp=67°-68° C. (lit. 16 68°-70° C.). NMR (AP-2-88-17, CDCl 3 ) δ: 7.55-7.35 (m, 5H), 4.82 (s, 1H), 3.78-3.65 (m, 4H), 2.59- 2.56 (t, 4H, J=4.7 hz). FTIR (AP-2-88-19): 2228 (CN), 1454 (methylene scissor), 1117 (C--O--C), 703, 739 (monosubstituted benzene).
EXAMPLE 2
4,4'-Bis(α-cyano-α-N-morpholino)benzyl benzophenone (52)
1.85 g (9.16 mmol) of α-(N-morpholino)benzyl cyanide (2, Ar=C 6 H 5 ) was dissolved in 12 mL of dry DMF along with 1.00 g (4.58 mmol) of 4,4'-difluorobenzophenone (13) in a dry round bottom flask under N 2 . After 15 m of stirring to homogenize the solution, 405 mg (9.23 mmol) of 60% NaH were added in one aliquot and immediately vigorous bubbling of H 2 , a slight exotherm and a change in color to greenish were observed. Within about 15 m, the color had changed to pale honey and stayed that way for 12 h of stirring that was allowed. Upon quenching the reaction mixture into ten fold excess ice-water, a white precipitate was collected and dried, yield=2.67 g (100%), mp 80°-122° C. (diastereomeric). NMR (AP-2-95-14, CDCl 3 ) δ: 8.00-7.00 (m, 9H), 3.90-3.70 (m, 4H), 2.70-2.40 (m, 4H).
EXAMPLE 3
4,4'-Bis(α-cyano-α-N-morpholino)benzyl Diphenyl Sulfone (53)
1.63 g (8.07 mmol) of α-(N-morpholino)benzyl cyanide (2, Ar=C 6 H 5 ) was dissolved in 12.5 mL of dry DMF along with 1.04 g (4.04 mmol) of 4,4'-difluorophenyl sulfone (16) in a dry round bottom flask under N 2 . After 15 m of stirring to homogenize the solution, 366 mg (17.7 mmol) of 60% NaH were added in one aliquot and immediately a vigorous bubbling of H 2 , a slight exotherm and a change in color to greenish were observed. Within about 15 min, the color had changed to pale honey and stayed that way for 12 hour of stirring that was allowed. Upon quenching the reaction mixture into ten fold excess ice-water, a white precipitate was collected and dried, yield=2.51 g (100%), mp 125-165 C. (diastereomeric). The crude sample was crystallized thrice from DMF-EtOH and from benzene-hexane 3 times to yield white, shiny flakes mp 145-220 C. Elemental analysis found: C:70.96, H: 5.65, S: 4.89. This analysis fits very well with C 36 H 34 N 4 O 4 S(0.5 C 6 H 6 ) i.e, with 1 mole of benzene as solvent of crystallization for every two moles of the compound (Calcd. C:71.21, H: 5.67, S:4.87). FTIR (AP-2-96-16/cm) : 1450 (methylene scissor), 1324, 1161 (sulfone), 1117 (C--O--C), 747 (monosubstituted benzene). NMR (AP-2-96-1, CDCl3) δ: 7.95-7.85 (m, 4H), 7.65-7.55 (m, 2H), 7.4-7.2 (m, 2H), 3.8-3.7 (m, 4H), 2.7-2.5 (m, 4H).
EXAMPLE 4
4,4'-Bis(benzoyl)diphenyl Sulfone (54)
1 g of 4,4'-bis(α-cyano-α-N-morpholino)benzyl diphenyl sulfone (52) was suspended in 25 mL of 70% AcOH and the mixture was refluxed. Within about 10 m, the solution had homogenized and in 5 more min, white solid started separating out. The mixture was cooled and the solid collected. Dry wt.=0.63 g (83), mp 192-195 C. It was recrystallized thrice from toluene-EtOH (9:1) to give shiny, colorless, fluffy crystals, mp 203.5-204 C. NMR (AP-2-93-20, CDCl 3 ) δ: 8.11 (d, 2H, J=8.2 hz), 7.92 (d, 2H, J=8.2 hz), 7.79 (d, 2H, J=7.5 hz), 7.65 (dd, 1H, J+7.6, 7.3 hz), 7.51 (dd, 2H, J=8.2 hz), 7.79 (d, 2H, J=7.5 hz), 7.65 (dd, 1H, J=7.6, 7.3 hz), 7.51 (dd, 2H, J=7.7, 7.4 hz). FTIR (AP-2-93-23,/cm): 1668 (CO), 1654 (C=C arom.), 1331, 1165 (sulphone), 704 (monosubstituted benzene). Elemental analysis: found (calcd) for C 26 H 18 O 4 S; C: 73.16 (73.22); H: 4.30(4.25); S: 7.77(7.52).
EXAMPLE-5
α,α'-Dicyano-α,α'-bis(N-morpholino-p-xylene (12, Ar=p-C 6 H 4 , R/R=CH 2 CH 2 OCH 2 CH 2 )
To a solution of 11.05 g (100 mmole) of NaHSO 3 in 300 mL of water were added 6.85 g (50 mmole) of terephthalaldehyde and the mixture was stirred for 2 h to give a homogeneous solution. 9.15 mL (100 mmol) of morpholine were added at this time and the solution was stirred for 2 more h to give a homogeneous solution of bis(aminal). A solution of 5.2 g (100 mmol) of NaCN in 100 mL of H 2 O was then added over a period of 2 h and the stirring was continued overnight. The pale cream solid was filtered and the dry crude solid weighed 16 g (100%), mp 224°-227° C. It was recrystallized from DMF - EtOH twice to yield off-white, shiny crystals, mp 230°-232° C. Elemental analysis: found (calcd. for C 18 H 22 N 4 O 2 ): C: 66.50 (66.23), H: 6.75 (6.80), N: 17.23 (17.17). FTIR (AP-2-76-23): 2230 (CN), 1510 (C=C arom.), 1458 (methylene scissor), 1112 (C--O--C), 803 (p-disubstituted benzene). NMR (AP-2-76-9, CDCl 3 ) δ: 7.61 (s, 2H), 4.85 (s, 1H), 3.85-3.69 (m, 4H), 2.7-2.52 (m, 4H).
EXAMPLE 6
Polymerization of Bisfluorophenyl Sulfone (16) and α,α'-Dicyano-α,α'-bis(N-morpholino)-p-xylene (12, Ar=p-C 6 H 4 , R/R=CH 2 CH 2 OCH 2 CH 2 ) to form Poly(α-aminonitrile) 17, Ar=p-C 6 H 4 , R/R=CH 2 CH 2 OCH 2 CH 2
a) At ca. 105° C.
3.026 g (9.271 mmol) of α,α'-dicyano-α,α'-bis(N-morpholino)-p-xylene (12, Ar=p-C 6 H 4 , R/R=CH 2 CH 2 OCH 2 CH 2 ) were dissolved along with 2.3574 g (9.2719 mmol) of bisfluorophenyl sulfone (16) at 105° C. (solution temperature) in a flame dried flask in dry DMF under N 2 . Upon the addition of 830 mg of 60% NaH (21 mmol), a vigorous bubbling and an immediate color change to deep maroon was seen. The solution was stirred for a total of 69 h and quenched in ice cold 5% aqueous NaCl to yield 4.97 g (99%) of a pale brown solid. Purification was done by dissolving it in 1:1 DMF:acetone and precipitation in water thrice. It was dried in a vacuum oven at 50° C. overnight. TGA (AP-3-12-16A): 10% weight loss (in air) at 252° C. followed by a 60% weight retention up to 500° C. and complete weight loss at 600° C. FTIR (AP-3-12-19, cm 1 ): 1676 (weak, CO), 1594 (arom. C=C), 1456 (methylene scissor), 1327, 1160 (sulfone) and 1117 (C--O--C). NMR (AP-3-12-21, CDCl 3 ) δ : 8.12-7 48 (m), 3.97-3.63 (br. s), 2.72-2.38 (m). Absolute molecular weight determination (AP-3-61-2) by GPC (in NMP at 60° C.) displayed a M n of 345 g/mol and M w of 3300 g/mol respectively.
b) At ca. 25° C.
3.6223 g (11.098 mmol) of α,α'-dicyano-α,α'-bis(N-morpholino)-p-xylene (12, Ar=p-C 6 H 4 , R/R=CH 2 CH 2 OCH 2 CH 2 ) were suspended along with 2.8216 g (11.098 mmol) of bis(fluorophenyl) sulfone (16) at ambient temperature in a flame dried flask in 25 mL dry DMF under N 2 . The mixture was stirred for 20 minutes and stayed heterogeneous because of the insolubility of the bis(aminonitrile) at the reaction temperature. Upon the addition of 1.02 g of 60% NaH (23.0 mmol), a vigorous bubbling and an immediate color change to deep maroon was seen. The solution was stirred for a total of 120 h and quenched into 250 mL ice cold 5% aqueous NaCl to yield 6.05 g (100%) of a pale yellow solid. Purification was done by dissolving it in DMF and precipitation in water once. Then it was twice precipitated from a CHCl 3 solution into ten fold excess ice cold MeOH. It was dried in a vacuum oven at 50° C. overnight. TGA (AP-3-59-21): 10% weight loss (in air) at 268° C. followed by a 60% weight retention up to 500° C. and complete weight loss at 640° C. FTIR (AP-3-60-6, cm -1 ): 1678 (weak, CO), 1591 (arom. C=C), 1452 (methylene scissor), 1331, 1158 (sulfone) and 1114 (C--O--C). NMR (AP-3-60-8, CDCl 3 ) δ: 8.1-7.3 (m), 4.0-3.6 (br. s), 2.7-2.4 (m). An absolute molecular weight determination by GPC (AP-3-60 -4) yielded an M n of 5,000 g/mole and an M w of 15,000 g/mole.
EXAMPLE 7
Poly(sulfonyl-p-phenylenecarbonyl-p-phenylenecarbonyl-p-phenylene)(18, Ar=p-C 6 H 4 )
1.00 g of the above material 17 was refluxed in 25 mL 30% AcOH for 1.5 h, the product was filtered and dried thoroughly after washing exhaustively with water and MeOH, 0.65 g (100%). A reduction in total mass of 36% corresponds to quantitative hydrolysis of the aminonitrile groups. TGA (AP-3-59-20) showed a 10% weight loss at 491° C. (i.e., an increase of 233° C. after the removal of the aminonitrile moiety). It was insoluble in any solvent that was tried, including toluene, DMF, acetone and THF.
EXAMPLE 8
α,α'-Dicyano-α,α'-bis(N-morpholino)-m-xylene (12, Ar=m-C 6 H 4 ,R/R=CH 2 CH 2 OCH 2 CH 2 )
To a solution of 11.2 g (100 mmol) of NaHSO 3 in 200 mL of H 2 O were added 7.0 g (50 mmol) of isophthalaldehyde (98%) and the mixture stirred to homogeniety for 2 h. 10 mL (106 mmol) of morpholine were then added in one aliquot and the solution was stirred for 2 h. 5.5 g (105 mmol) of NaCN were then added in one aliquot and the beaker was transferred to a steam bath where it was heated for 8 h with occasional stirring. The filtered pale yellow solid was dried to yield 15.9 g (100%) of product which was crystallized twice from 95% EtOH to obtain a pale yellow powder, mp 118.5°-135.5° C. After thorough drying, it was placed in a fritted disc funnel, washed with 200 mL of 95% EtOH by gravity filtration and dried in a vacuum oven at 60° C. overnight. NMR (AP-3-75- 18, CDCl 3 ) showed peaks at δ 7.70 (d, 1H, J=11.9 hz), 7.59 (d, 2H, J=7.4 hz), 7.50-7.44 (dd, 1H, J=6.8 hz, 8.53 hz), 4.85, 4.84 (1H, diastereomeric acidic proton), 3.9-3.7 (m, 8H) and 2.8-2.5 (m, 8H). FTIR (KBr disc, cm -1 ): 2228 (v. v. weak, CN), 1456 (phenyl), 1113 (C--O--C) and 760 (m-disubs. phenyl). Elemental analysis: found (calcd. for C 18 H 22 N 4 O 2 ): C: 66.23 (66.24), H: 6.80 (6.80) and N: 17.14 (17.17).
EXAMPLE 9
Polymerization of Bis(fluorophenyl) Sulfone (16) and α,α'-Dicyano-α,α'-bis(N-morpholino)-m-xylene (12, Ar=m-C 6 H 4 , R/R=CH 2 CH 2 OCH 2 CH 2 ) to form Poly(α-aminonitrile) 17, Ar=m-C 6 H 4 , R/R=CH 2 CH 2 OCH 2 CH 2
3.6608 g (11.216 mmol) of α,α'-dicyano-α,α'-bis(N-morpholino)-m-xylene (12, Ar=m-C 6 H 4 , R/R=CH 2 CH 2 OCH 2 CH 2 ) were dissolved along with 2.8520 g (11.217 mmol) of bis(fluorophenyl) sulfone (16) at ambient temperature in a flame dried flask in dry DMF under N 2 . The mixture was stirred for 20 minutes and was completely homogeneous at room temperature. Upon the addition of 1.04 g (24.5 mmol) of 60% NaH, a vigorous bubbling and an immediate color change to pale yellowish and then yellowish green was seen. After 24 h, the color of the reaction mixture was brown and the temperature was raised to 50° C. and the stirring continued. The color changed to a pale orange in 0.5 h and was pale honey after 24 h of stirring at 50° C. The temperature was then raised to 72° C. and stirring continued for 24 h, at the end of which an increase in the solution viscosity was evident. The solution was quenched in ice cold 5% aqueous NaCl to yield 6.1 g (100%) of a pale yellow solid. Purification was done by dissolving it in DMF and precipitation into water. Then it was twice precipitated from CHCl 3 solution into ice cold MeOH. It was dried in a vacuum oven at 50° C. overnight. TGA (AP-3-68-8): 10% weight loss (in air) at 298° C. FTIR (AP-3-67-23, cm -1 ): 1678 (weak, CO), 1591 (arom. C=C), 1452 (methylene scissor), 1331, 1158 (sulfone) and 1114 (C--O--C). NMR (AP-3-67-21, CDCl 3 ) δ: 8.2-7.2 (m, 12H), 4.0-3.5 (br. s, 8H), 2.7-2.2 (br. s, 8H). DSC (AP-3-68-20) showed a relatively large exotherm at 278° C., indicative of some reaction on the first heat. On the second heat, the maximum had shifted beyond the range of heating (i.e., at ca. 370° C.). Absolute molecular weight determination by GPC (AP-3-68-14) yielded a M n of 32,300 g/mole and a M w of 44,000 g/mole.
EXAMPLE 10
Poly(sulfonyl-p-phenylenecarbonyl-m-phenylenecarbonyl-p-phenylene) (18, Ar=m-C 6 H 4 )
1.0 g of the above material (17, Ar=m-C 6 H 4 , R/R=CH 2 CH 2 OCH 2 CH 2 ) was refluxed in 25 mL 30% AcOH for 1.5 h, filtered and dried thoroughly after washing exhaustively with water and MeOH, 0.65 g (100%). A reduction in total mass of 36% corresponds to quantitative hydrolysis of the aminonitrile groups. TGA (AP-3-68-9) showed a 10% weight loss at 478° C. (i.e., an increase of 180° C. after the removal of the aminonitrile moiety). An absolute molecular weight determination by GPC (AP-3-68-17) yielded an M n of 16,400 g/mole and an M w of 30,600 g/mole. DSC (AP-3-68-23) showed a T g of 192° C. on the first heat, a crystallization exotherm with a maximum at 242° C. and a T m of 257° C. On the second heat, a T g of 195° C. was noted with no signs of T m .
It is understood that the description and examples etc., provided herein are only exemplary and not limiting and that various modifications and changes in light thereof may be suggested to one of ordinary skill in the art and all such changes and modifications are deemed to be within the purview and scope of the present invention and accompanying claims.
REFERENCES
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A new method for preparing commercially valuable polymeric ketones is described. The method employs an α-amiononitrile as a monomeric unit whereby an amorphous, soluble polymer having protected carbonyl moiety is obtained. Upon deprotecting the carbonyl moiety, a crystalline polymeric ketone is obtained. The method allows production of polymeric ketone materials having aromatic, aliphatic or mixed aromatic/aliphatic backbones.
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Cross Reference to Related Applications
[0001] This non-provisional United States (U.S.) patent application claims the benefit of U.S. Provisional Application No. 60/388,923, filed on Jun. 14, 2002 by inventor Laurance F. Wygant entitled “Sharing Data using a Configuration Register.”
BACKGROUND
[0002] In a multiprocessor computer system where coordination among processors is necessary during system startup, two or more processors may need to communicate very early during the startup process at a time when key components of the system, such as, for example, a read-write memory system, are not yet functional, and therefore when the support for such communication is limited.
[0003] For example, processors may need to communicate at startup because they operate at different frequencies and need to synchronize at a common frequency in order for the system operate correctly. Each processor, in turn, may have multiple frequencies at which it is able to operate. A processor may be designed to operate at a lower frequency in order to conserve power or to reduce heat dissipation, and switch to a higher frequency when it is necessary to use a maximum computing power or when heat dissipation is not a significant constraint. In these situations each of the multiple frequencies at which the processor may operate may need to be synchronized with the corresponding frequencies in all the other processors, and robust methods to perform such synchronization at startup and handle errors while dealing simultaneously with the absence of key system components are necessary.
[0004] In order for two concurrently executing threads in two different processors to synchronize internal parameters such as clock frequencies, the two threads need a communication and coordination mechanism. In a shared memory implementation of such a mechanism, a read/write memory area may be used to store coordination variables such as semaphore bits that allow the processors to signal each other when specific events occur, as well as to store the data that is actually communicated between the two threads.
[0005] In one embodiment of such a system, a predetermined setting such as a jumper configuration selects one of the several processors in a multiprocessor system to initiate startup. This processor is designated as the bootstrap processor (BSP). The BSP is responsible for starting up the other processors, known as application processors or APs. There may not be any difference between the BSP and APs, though it is necessary that each processor be able to determine whether it is the BSP or an AP once a BSP has been selected. In such systems, data is passed between the APs and the BSP in order for startup to be completed successfully and also for synchronizing the frequency setting of all of the processors including the BSP, in systems where frequency synchronization must be a part of startup.
[0006] A complication that arises in the scenarios described is that because such actions must occur early in the startup process, the memory subsystem of the computer may be unavailable for use as a read/write storage area supporting communication between the processors. This may happen because Dynamic Random Access Memory (DRAM) memory subsystems such as Rambus Direct DRAM (RDRAM) or Double-Data-Rate DRAM (DDR RAM), for example, require initialization and set-up before use. Memory initialization, in turn, requires processor action and therefore that the processors in the computer system have already started and are running—and so, processor startup cannot rely on system memory for interprocessor communication.
[0007] In another instance, the process of processor startup may itself require that status data be communicated between the BSP and an AP very early in the startup process. On system boot, the BSP needs to discover the processors in the system and determine if they are functional. As stated before, this is a protocol that may be executed very early in system startup and therefore may need a shared storage space other than system RAM to implement data communication between the BSP and AP, if system RAM is not available at the time this protocol executes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] [0008]FIG. 1 is a high-level block diagram of a multiprocessor computer system in one embodiment of the claimed subject matter.
[0009] [0009]FIG. 2 is a high-level flowchart of data sharing in one embodiment of the claimed subject matter.
DETAILED DESCRIPTION
Multiprocessor Computer System
[0010] [0010]FIG. 1 shows a high-level block diagram of a multiprocessor computer system including an embodiment of the claimed subject matter. This system may in general include several processors, for example the processors 100 and 102 in the figure. One of the processors in this embodiment is designated the bootstrap processor (BSP) at startup, for example, by some deterministic protocol. The other processors are termed application processors (APs). The processors are socketed into a system board. Using board logic and interconnect, the processors are able to access a shared memory subsystem 110 by means of a bus such as a front side bus (FSB) 140 , and a memory controller which is part of an integrated device 120 . In other embodiments of the claimed subject matter, there may be more than two processors and the bus configuration connecting them to memory and other parts of the system may differ; moreover, the processors may not be part of a general purpose computer system as depicted in FIG. 1, but rather part of any device that uses digital processing capabilities, including digital communication devices such as telephones, or network routing devices; hand held devices such as Personal Digital Assistants (PDAs) and dedicated subsystems included in other digital devices such as a digital television set top box or digital display devices, a digital game console, or a web terminal, among others.
[0011] The memory subsystem of the computer system 110 in one embodiment of the claimed subject matter may be one of several types, including for example, an RDRAM, DDR RAM, or Synchronous DRAM (SDRAM) memory subsystem, depending on the specific characteristics of the memory controller 110 and other board logic.
[0012] Typically, the processors are also connected to one or more local buses via a bridge. In the embodiment shown in the figure, the integrated device 120 combines the functionality of the memory controller and a bridge that connects the front side bus to a pair of local buses, for example, buses 130 and 132 , each of which conforms to the Peripheral Component Interconnect (PCI) Local Bus Specification version 2.3 (PCI bus). In this embodiment, the bridge provides logic and various control functions that allow the processors to address, configure, and exchange data with devices on the bus and the controller itself. In this embodiment, one of the PCI buses, 130 , is a 64-bit bus that operates at 66 MHz and the other, 132 , a 32-bit bus that operates at 33 MHz. The FSB also connects via a second bridge 122 to a lower speed Industry Standard Architecture (ISA) bus 166 , to a Universal Serial Bus (USB) 160 , an Integrated Drive Electronics (IDE) bus 162 , and low-speed input/output devices such as a Mouse, Keyboard and Floppy Disk Drive 164 .
[0013] These low-speed devices are specific to the general purpose computer embodiment of the claimed subject matter depicted in FIG. 1 and may differ in other embodiments, or be entirely absent, for example, in a game console or a cellular telephone embodiment of the claimed subject matter.
PCI Bus
[0014] Each of the PCI buses in the embodiment of FIG. 1 supports multiple devices that may be accessed by either of the processors. As shown in the figure, the 64-bit PCI bus is connected to a Small Computer Systems Interface (SCSI) controller to which may be attached one or more mass storage devices 181 , and the 32-bit PCI bus to a network adapter 190 and a video and graphics card 192 . Other PCI devices may be installed into the computer system using 32-bit PCI slots 194 , 196 or 198 ; or 64-bit PCI slots 182 , 184 and 186 .
PCI Configuration Mechanism
[0015] The PCI subsystem comprising the bus, controller and PCI devices, allows for system and device configuration by each of the processors. This is implemented by the provision of a pair of PCI registers in the controller termed the PCI Configuration Address Port (PCI-CAP), accessible to each of the processors at I/O addresses 0CF8-0CFB, and the PCI Configuration Data Port, accessible at I/O addresses OCFC-OCFF which allow address to the PCI Configuration Space. The PCI Configuration Space in general stores PCI device and other system related configuration information.
[0016] The layout of the 32-bit PCI-CAP is detailed in Table 1. More details are available in the PCI Local Bus Specification version 2.3.
[0017] As can be seen from the Table, bit 31 of the PCI-CAP is the enable bit. In a “normal mode” of operation, that is, when the PCI-CAP is used in conformance with the PCI specification, a processor (termed the “host processor”) writes a 32-bit word to the PCI-CAP in compliance with the template in Table 1 and the PCI-CAP is interpreted as indicated in the table.
TABLE 1 Normal Use Allocation of Bit fields in PCI-CAP Bits Purpose 0-1 Reserved, 0s 2-7 Address of target double word in target function's configuration space 8-10 Address of function number (one of eight) within the target PCI device 11-15 Address of target PCI device 16-23 Address of target PCI bus 24-30 Reserved, 0s 31 “enable bit” - 1 to enable configuration
[0018] In this normal use scenario, the device specified by bits 11 - 15 , coupled to the bus specified by bits 16 - 23 , the function specified by bits 8 - 10 for that device, and the double word specified by bits 2 - 7 within the configuration space of the function for the device, are selected when the processor writes to the PCI-CAP. The next write to the PCI Configuration Data Port then causes the data written to the Data Port to be loaded into the specified function and double word, thus allowing the host processor to access the various configuration functions and parameters in the PCI device.
[0019] However, the PCI-CAP has no defined purpose when it is loaded with a 32-bit word that is not in compliance with the template, specifically when the enable bit is set to 0. It is by exploiting this situation, that one embodiment of the claimed subject matter performs a data passing method using the PCI-CAP to transfer data between the BSP and an AP by setting the enable bit to 0 and then using the remaining bits of the PCI-CAP as shared memory. In one embodiment of the claimed subject matter, this fact is used to allow data transfers between processors in general to occur by use of the PCI-CAP with the enable bit (bit 31 ) set to 0. FIGS. 2 and 3 provide a high level flowchart of an algorithm for this purpose that is used in this embodiment of the claimed subject matter.
[0020] In this embodiment, the data passing method above takes place when two threads executing concurrently either on the same or on different processors execute in a coordinated fashion. Two bits from the PCI-CAP register are chosen to represent an ready bit and a done bit.
[0021] A simplified flowchart depicting this method is shown in FIGS. 2 and 3. The first thread, termed the initiator thread 200 in the flowchart in FIG. 2, first clears the enable bit of the PCI-CAP preventing its use as a configuration register, as in block 205 of the FIG. and clears the done bit that the responding thread will use to signal completion. It then stores data in the PCI-CAP, and sets a ready bit to indicate to the second thread that the data is ready, as depicted in blocks 210 and 215 . The initiator thread then starts a second thread, the responder thread, waits for the latter to indicate that it is active (data ready bit and enable bits are both 0), and then waits for the second thread to be done (enable bit and done bit are both 0), with timeout handling (blocks 225 - 255 ). FIG. 3 depicts the second thread, termed the responder thread 300 . On waking up after basic error checking ( 302 ), the thread signals that it is active (clears ready bit in 305 ). The thread may optionally use the PCI-CAP for configuration addressing, and to do so must save the contents including the data from the first thread, as in block 330 depicting steps 335 - 355 . To use the PCI-CAP in this manner, the second thread first saves any data passed from the initiator in 335 , then sets the enable bit to signal that it is starting normal use of the PCI-CAP 340 , performs configuration 345 , and then restores the data 355 after clearing the enable bit 350 . Once the data is processed, the second thread signals the availability of its results in the PCI-CAP by setting the done bit 325 . The first thread can then read the results produced by the second (block 255 , FIG. 2).
[0022] In one embodiment of the claimed subject matter this method is applied to coordinate processor startup and to allow processors to synchronize frequencies. The details of this startup process are part of the subject matter of another patent application by the Applicant and therefore are not disclosed here. U.S. patent application Ser. No.______, Laurance Wygant Coordination of Multiple Multi-Speed Devices, filed Mar. 31, 2003. It will be clear to one skilled in the art, however, that the above data passing method can be used for various types of inter-processor and other inter-device communication tasks in other embodiments.
Embodiments of the Claimed Subject Matter
[0023] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the claimed subject matter. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments
Implementation of Methods
[0024] Embodiments of the claimed subject matter include various steps. These steps may be performed by hardware components, or may be embodied in machine-executable instructions, which may be used to cause a general-purpose or special-purpose processor or logic circuits programmed with the instructions to perform the steps. Alternatively, the steps may be performed by a combination of hardware and software. An embodiment of the claimed subject matter may be provided as a computer program product or as part of the Basic Input/Output System (BIOS) of a computer that may include a machine-readable medium having stored thereon data which when accessed by a machine may cause the machine to perform a process of the claimed subject matter. The machine-readable medium may include, but is not limited to, floppy diskettes, optical disks, DVD-ROM disks, DVD-RAM disks, DVD-RW disks, DVD+RW disks, CD-R disks, CD-RW disks, CD-ROM disks, and magneto-optical disks, ROMs, RAMs, EPROMs, EEPROMs, magnet or optical cards, flash memory, or other type of media/machine-readable medium suitable for storing electronic instructions. Moreover, an embodiment of the claimed subject matter may also be downloaded as a computer program product, wherein the program may be transferred from a remote computer to a requesting computer by way of data signals embodied in a carrier wave or other propagation medium via a communication link (e.g., a modem or network connection).
[0025] Many of the methods are described in their most basic form but steps can be added to or deleted from any of the methods and information can be added or subtracted from any of the described messages without departing from the basic scope of the claims. It will be apparent to those skilled in the art that many further modifications and adaptations can be made. The particular embodiments of the claimed subject matter are not provided to limit the claims but to illustrate it. The scope of the claims is not to be determined by the specific examples provided above but only by the claims themselves as provided below.
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A first execution thread disabling configuration access to a register that is otherwise dedicated to a storage of a configuration parameter, the first execution thread storing data other than the configuration parameter in the register and a second execution thread accessing the data from the register.
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FIELD OF THE INVENTION
This invention relates to the field of controlling the use of disposable elements and is especially useful for authenticating and verifying suitability of disposable elements for clinically useful systems for treating cells with photoactivatable compounds and radiation which activates the compound thereby affecting the cells such as for the extracorporeal treatment of blood cells, especially leukocytes, with UV radiation.
BACKGROUND OF THE INVENTION
It is well-known that a number of human disease states may be characterized by the overproduction of certain types of leukocytes, including lymphocytes, in comparison to other populations of cells which normally comprise whole blood. Excessive or abnormal lymphocyte populations result in numerous adverse effects to patients including the functional impairment of bodily organs, leukocyte mediated autoimmune diseases and leukemia related disorders many of which often ultimately result in fatality.
U.S. Pat. Nos. 4,321,919; 4,398,906; 4,428,744; and 4,464,166 to Edelson describe methods for treating blood whereby the operation or viability of certain cellular populations may be moderated thereby providing relief for these patients. In general, the methods comprise treating the blood with a dissolved photoactivatable drug, such as psoralen, which is capable of forming photoadducts with DNA in the presence of U.V. radiation. It is believed that covalent bonding results between the psoralen and the lymphocyte nucleic acid thereby effecting metabolic inhibition of the thusly treated cells. Following extracorporeal radiation, the cells are returned to the patient where they are thought to be cleared by natural processes but at an accelerated pace believed attributable to disruption of membrane integrity, alteration of DNA within the cell, or the like conditions often associated with substantial loss of cellular effectiveness or viability.
Although a number of photoactivatable compounds in the psoralen class are known, 8-methoxy psoralen is presently the compound of choice. An effective radiation for this compound, and many psoralens in general, is the ultraviolet spectrum in the range of approximately 320 to 400 nanometers, alternatively referred to as the U.V.A. spectrum. As the development of photoactivatable compounds proceeds, it may be expected that changes in the preferred activation radiation spectrum will be necessary. Suitable selection of radiation sources will, of course, increase treatment efficiency and is contemplated as an obvious optimization procedure for use with the inventions disclosed herein.
Although Edelson's methods have been experimentally shown to provide great relief to patients suffering from leukocyte mediated diseases, numerous practical problems require solutions. In particular, Edelson fails to provide a suitable apparatus for applying radiation to the cells, e.g. via a treatment station, in an economical and efficacious manner, or a system for incorporating a treatment station providing for the treatment of a patient in a clinically acceptable format.
Conventional techniques for photoactivating compounds associated with cells have relied on a plurality of devices including flasks, filtration columns, spectrophotometer cuvettes, and petri dishes. The sample to be irradiated is added to the containers and the container placed adjacent to the radiation source. Such systems tend to be laboratory curiosities as they fail to provide the necessary safeguards intrinsically necessary where patient bodily fluids are concerned, particularly since these fluids must be returned to the patient thereby necessitating strict avoidance of contamination. Further, such methods tend to be volume limited, are characterized by many mechanical manipulations and are generally unacceptable from a clinical and regulatory viewpoint. It is an object of the present invention to provide methods and apparatus suitable for use with the Edelson methods to overcome the limitations associated with the conventional expedients.
Copending application U.S. Ser. No. 650,602, describes a practical device for coupling the radiation provided by commercially available light sources, such as the so-called "black-light" fluorescent tubes, to cells for treatment by Edelson's photoactivated drug methods. In summary, the disposable cassette described therein comprises a plurality of fluorescent tube-like light sources such as the U.V.A. emitting Sylvania F8TS/BLB bulb, which are individually, coaxially mounted in tubes of larger diameter which are, in turn, coaxially mounted in sealing arrangement within second outer tubes of even larger diameter thereby forming a structure having two generally elongated, cylindrical cavities about each radiation source. The inner cavity preferably communicates with the atmosphere thereby facilitating cooling of the radiation source. The second tube forming the outer cavity further comprises inlet and outlet means for receiving and discharging, respectively, the cells to be irradiated. A plurality of these structures are "ganged" and suitable connections made between inlets and outlets of adjacent members to provide for serpentine flow of cells through each outer cavity. Thus, continuous flow of the cells through the plurality of cavities surrounding the centrally disposed radiation sources facilitates thorough treatment of the cells. Additional, detailed description of the Taylor device may be obtained by direct reference to U.S. Ser. No. 650,602.
To be fully practical, the Taylor device requires a clinically acceptable instrument to house the device and to provide the cells to be treated in an appropriate form. Such an instrument is the object of the inventions described in U.S. Pat. Nos. 4,573,960, 4,568,328, 4,578,056, 4,573,961, 4,596,547, 4,623,328, and 4,513,962, fully incorporated herein by reference. While the instruments described therein work well, it is an object of the instant application to describe improved systems capable of implementing, in advanced fashion, the medical treatment principles first taught by Edelson.
It is another object of the present invention to provide still further improvements in greater patient safety and comfort while reducing treatment time and cost, by utilizing newly designed disposable irradiation chambers and light array assemblies in a patient treatment instrument.
It is yet another object to provide an improved instrument which meets the above criteria along with all the positive attributes of the prior system; compactness, mobility, completeness, fully automated and monitored, and ease of operation.
It is a further related object of this invention to provide in contrast to the time consuming batch like processing of the prior system, continuous on-line patient treatment wherein collection, separation, and cell treatment occur simultaneously, thereby reducing treatment time and increasing patient safety and comfort.
It is still a further object to provide improved methods for monitoring the use of disposables including methods to authenticate a disposable prior to its initial use and to monitor its services and prevent overuse.
BRIEF DESCRIPTION OF THE DRAWING
The drawing depicts a rear elevational view of one embodiment of the combination of the present invention. The drawing shows a disposable flat plate irradiation chamber (10) which has permanently mounted thereto an integrated circuit mounted on a circuit board (12).
SUMMARY OF THE INVENTION
In accordance with the principles and objects of the present invention there are provided electronic means to authenticate and verify the suitability of the disposable elements for use and for monitoring the service time of such disposable for preventing overuse. The invention is especially useful with apparatus for "on-line" extracorporeally photoactivating a photoactivatable agent in contact with blood cells. Such a patient treatment apparatus collects and separates, on a continuous basis, blood from a patient while the patient is connected to the apparatus, returning undesired blood portions obtained during separation while photoactivating desired portions and thereafter returning thusly treated cells to the patient. As a result of this novel approach, the patient treatment systems optimize and minimize treatment time by concurrently conducting various aspects of such photoactivation treatment which were previously performed sequentially. Such a patient treatment system preferably utilizes two different disposable treatment elements comprising an irradiation chamber for containing the patient cells/fluid for exposure to photoactivating irradiation, and a light array assembly for providing the activating irradiation. The instant invention, while having broad applicability, is especially useful for authenticating these treatment elements prior to use and, in the case of the light array assembly, for monitoring the length of service to prevent use beyond the service life. The most preferred embodiment of the present invention comprises an electronic memory element which contains information characteristic to the treatment element in question. The memory element, typically an integrated circuit (IC), has associated contact points for electronic connection to, and communication with the apparatus for which the disposable is intended. Upon installation of the disposable into the apparatus, electrical contact is made with the memory IC and permits the apparatus to verify the disposable is in appropriate condition for use. Inappropriate, counterfeit, improper use can then be avoided by suitably programming the apparatus not to operate in those circumstances. A most preferred embodiment of the memory IC will be an electrically erasable programmable read only memory (EEPROM) which will be capable of receiving information from the apparatus thereby allowing interaction therebetween and thus monitoring of the service life of the disposable to prevent overuse. It will be recognized that the instant invention will serve to increase patient safety by ensuring that disposable treatment elements, meeting critically determined operating parameters are used and not readily circumvented by unproven, potentially failure prone and therefore hazardous disposable element copies.
DETAILED DESCRIPTION
The system developed for extracorporeally treating a patient are the result of a number of separate inventions some of which form the subject matter of previously described issued patents and copending commonly assigned applications including U.S. Ser. No. 834,292 entitled "Concurrent On-Line Irradiation Treatment Process"; U.S. Ser. No. 834,294 entitled "Disposable Temperature Probe For Photoactivation Patient Treatment System"; U.S. Pat. No. 4,681,568 entitled "Improved Valve Apparatus For Photoactivation Patient Treatment System"; U.S. Ser. No. 834,256 entitled "Light Array Assembly For Photoactivation Patient Treatment System"; U.S. Pat. No. 4,692,438 entitled "Pump Block For Interfacing Irradiation Chamber to Photoactivation Patient Treatment System"; U.S. Ser. No. 834,260 entitled "Demountable Peristaltic Pump For Photoactivation Patient Treatment System"; U.S. Pat. No. 4,687,464 entitled "Zero Insertion Force Socket For Photoactivation Patient Treatment System"; and U.S. Ser. No. 834,258 entitled "Irradiation Chamber For Photoactivation Patient Treatment System", the relevant parts of which are fully incorporated herein by reference. While a brief description of that patient treatment system may prove helpful to understand the nature of the disposable treatment elements used therein, it will be readily understood that the instant invention is not so limited.
The operation of the device and performance of the methods can be divided into two basic phases or modes. The first phase occurs when the patient is connected to the treatment apparatus by venipuncture or the like methods well-known and developed to a high degree in the dialysis arts. Patient blood, as it flows to the apparatus is preferably infused with an anticoagulant agent. Control of the flow of patient blood throughout the apparatus is largely controlled by a series of clamps controlled by the central processing unit under software and operator interactive control.
Normally the blood flows by action of a peristaltic pump (preferably a roller pump such as that described in U.S. Pat. No. 4,487,558 to Troutner entitled "Improved Peristaltic Pump" and fully incorporated herein by reference) through tubing into a continuous centrifuge. This continuous centrifuge, available commercially from suppliers such as Dideco, Haemonetics and others, is preferably capable of continuously separating blood based on the differing densities of the individual blood components. "Continuously", as used herein means that, as blood flows into the centrifuge, it accumulates within the rotating centrifuge bowl and is separated so that low density components are emitted after a certain minimum volume has been reached within the centrifuge bowl and as additional blood is added. Thus, the continuous centrifuge in effect acts as a hybrid between a pure online system and a pure batch system. This occurs because the centrifuge bowl has a capacity to hold most, if not all, of the most dense portion, typically erythrocytes or red blood cells while emitting lower density portions such as plasma and leukocytes (white blood cells) as whole blood is continuously added. At some point, however, the reservoir volume of the centrifuge is filled with the higher density components and further separation cannot be effectively obtained. Prior to that point, the operator, by directly viewing the uppermost portion of the centrifuge bowl through the centrifuge cover, can detect qualitatively when the centrifuge emits plasma (as opposed to priming solution), leukocyte enriched portions and the remainder, i.e., nonleukocyte enriched portions, including erythrocyte enriched portions. Based on the operator's observations, he or she enters via the control panel the identification of the individual blood portions as they are emitted from the centrifuge. In response to this information, the apparatus controls valve mechanisms to direct the leukocyte enriched portion and a predetermined volume of plasma into plasma-leukocyte enriched container while excess plasma, air, priming fluids, erythrocytes etc. are directed to a return container for reinfusion to the patient.
Once the centrifuge is no longer capable of further separation due to the attainment of its capacity, the operator directs that the bowl be emptied by suitable data key entry on the control panel and the fluid contents of the centrifuge are advantageously pumped into the return container. The foregoing steps may be repeated a number of times or cycles before the desired volume of leukocyte enriched blood and plasma is obtained for further treatment, in each instance the undesired portions being collected in the return container.
Between cycles, the fluids, including erythrocytes which have been pumped into the return container are gravity fed back to the patient through a drip infusion operation. It is preferred that gravity feed be employed rather than actively pumping the blood back to the patient in order to avoid potential pressurization problems at the infusion insertion site at the patient, and also to avoid foaming or other air related dangers.
The leukocyte enriched container is also connected via a tubing line to a disposable flat plate irradiation chamber located within the apparatus. The chamber has a return tubing line to the leukocyte enriched container so that the fluids can be recirculated by means of another peristaltic roller pump through the flat plate irradiation chamber.
The irradiation chamber disposable can assume a variety of mechanical configurations but, in its most preferred embodiment, possess a serpentine pathway dimensioned to provide a large surface area to volume ratio thereby exposing a predominant portion of the patient fluids to photoactivating radiation. The chamber is ideally constructed of a material which is substantially transparent to the particular photoactivating radiation, chosen based on the type of photoactivatable agent employed. The most preferred embodiment of the patient treatment system employs a disposable irradiation chamber which is adapted to be received between two rows of irradiation sources, the disposable light array assembly, and to receive activating radiation simultaneously on both sides of the irradiation chamber. Thus, when the irradiation chamber is filled with patient fluid/cells, the light array assembly which surrounds the chamber is energized to provide the activating illumination. During illumination the recirculation pump rotor recirculates the patient fluid from the container through the chamber between the energized light array and back to the container. After a predetermined level of photoactivation has been achieved, the light array assembly is deenergized, the patient cells are pumped to the return container and then reinfused back to the patient. Ideally, operation of the patient treatment apparatus is largely under the control of a software programmed, electronic central processing unit (CPU) but subject to operator input. The CPU monitors the clamps, pumps, and safety devices throughout the apparatus to ensure patient safety and treatment efficiency. The CPU also communicates with the IC memory elements associated with the disposable.
The disposable flat plate irradiation chamber treatment element and the disposable light array assembly are more fully described in copending applications Ser. No. 834,258 and U.S. Ser. No. 834,256, respectively, and incorporated herein by reference.
The foregoing described patient treatment methods depend in large measure upon the quality and construction of the disposable flat plate irradiation chamber and the disposable light array assembly for safe and effective medical treatment. In the instance of the flat plate chamber it is important that it be sterile and unused (and therefore uncontaminated with the presence of possibly incompatible tissue types), made of materials appropriate to transmit the wavelength of radiation being employed, and that it be structurally sound and thus not subject to operational failure. In the instance of the light array assembly it is advantageous that the lights are of such construction and operation that the radiation intensity, distribution, and wavelength are appropriate and certifiable for the intended application. Since radiation characteristics of the light array degrade with usage, monitoring service to prevent overuse and thus reduced treatment efficacy is also of paramount importance. Because it is likely that arrays of differing radiation characteristics will be used for differing medical treatments, ensuring proper array--system interaction is also highly desirable.
Thus, for safe and effective medical treatment, it is clear that the photopheresis patient treatment system ideally will receive information from the disposables to enable it to determine that (1) the flat plate irradiation chamber is new and unused, (2) the flat plate chamber was manufactured of proper construction by a certifiable source, (3) the light array assembly was manufactured using proper irradiation sources from a certifiable source, (4) the specific type of light array assembly, and (5) the total accumulated time of usage of the light array assembly. The IC memory device, individually associated with each disposable meets these needs of authentication and verification in the following manner.
Each disposable includes as a permanently mounted feature, a solid state memory device, which can be written to or read from by an electronic microprocessor such as the central control microprocessor of the patient treatment system. The memory device, typically an integrated circuit device (or element as sometimes used herein), is ideally non-volatile in that it can retain stored information indefinitely without requiring an electrical power source. Such a device is commercially available and is commonly known as an EEPROM available under the brand name NOVRAM from XICOR Inc., California. Electrical connections between the IC memory element and the central control microprocessor of the apparatus can be readily accomplished through "finger-type" contacts on a circuit board on which the IC memory element is mounted and electrically connected. Thus, upon installation of the disposable with the IC memory device, the finger contacts are inserted into an electrical plug in type socket such as is described in U.S. Pat. No. 4,687,464.
During manufacture of the disposable, the IC memory element is ideally encoded, in a known manner, by a computer with disposable specific characteristic data such as serial number, type, certification code, and, if applicable, maximum usage time. When installed in the apparatus, the central control microprocessor, with preprogrammed instructions regarding the manner of encoding, can decode the disposable characteristic information to verify authenticity and certification, determine type of disposable and adjust procedure accordingly. In applicable instances, it can also periodically decrement the available usage time so that the operator of the apparatus can be warned when the disposable's useful lifetime has expired. Optionally, one can program the apparatus using the disposable-IC memory device to reject an `expired` disposable or prohibit further useage thereof.
It will be readily apparent that many types of information can be stored in the IC memory device to regulate the use of a disposable. Further, while examples of use of the instant invention have been provided with respect to its use in photoactivated patient treatment systems, innumerable applications are apparent. These include any instance where it is necessary or desirable to control the use of disposable elements and/or prevent the use of unauthorized disposable elements. Additionally, while a most preferred IC memory element has been described, other non-volatile read/write memory devices may be equally useful including for instance magnetic recording strips or even electronic chips which require power sources to maintain a memory. Obvious disadvantages with the latter include possible decreased shelf-life and increased expense incurred with additional components.
Upon study of the foregoing description, numerous alternatives may occur to the skilled artisan without departing from either the spirit or scope of the instant invention.
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Authentication and verification of suitability for use of disposable elements can be made by evaluation of characteristic data stored on a non-volatile read/write memory element, especially useful in a photoactivatable agent patient treatment system wherein photoactivatable agents, in contact with patient blood cells, are irradiated extracorporeally and then returned to the patient.
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CROSS-REFERENCE TO RELATED APPLICATION
This application is a Continuation of U.S. application Ser. No. 11/589,961 filed on Oct. 31, 2006, and claims priority from U.S. application Ser. No. 11/589,961 filed on Oct. 31, 2006, which claims priority from Japanese Patent Application No. 2005-317872, filed on Nov. 1, 2005, the entire disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
This invention relates to a reconfigurable processor and a reconfigurable apparatus.
In recent years, a processor has been demanded to have not only performance of computing data being constantly input in real time at a high speed, but also high versatility to facilitate changing of an implemented logic.
For example, in a case of a processor used in a network security field, performance of computing communication data being constantly input in real time at a high speed, and versatility which enables frequent updating of an algorithm for detecting abnormalities of the communication data, or a pattern file have been required.
In a case of a processor used in a video processing field, performance of computing video data constantly input in real time at a high speed, and versatility of performing various processings for the video data by combining a plurality of operations such as encoding/decoding, down-conversion, copyright information addition, division, synthesis, and format conversion have been required.
However, the high versatility to facilitate changing of the implemented logic cannot be obtained by ASIC which includes a dedicated circuit. The high-speed computing processing performance of the real-time data cannot be obtained by a general-purpose processor.
As a processor to simultaneously realize the two performances, a processor called a reconfigurable processor (RP) has been developed and has been attracting attention. This processor is largely classified into three systems, that is, an AND-OR system, a look up table (LUT) system, and an ALU (Arithmetic Logical Unit) system.
The AND-OR system is a system which uses an AND-OR logic array as a logical element. According to this AND-OR system, high density of logics can be achieved because of small logical units (refer to U.S. Pat. No. 4,609,986).
The LUT system is a system which uses a LUT composed of a synchronous random access memory (SRAM) as a logical element. A high-level random logic is realized by prerecording a value of each input signal to the LUT (refer to U.S. Pat. No. 4,642,487).
The ALU system is a system which uses an ALU having functions of computing, retiming, and a memory predesignated as a logical element. It is called a dynamic reconfigurable processor (DRP). This computer system can change an implemented logic by one clock cycle, and has high versatility (refer to WO 02/095946).
The processor of the ALU system includes a reconfigurable circuit composed of a logical element having functions of computing, retiming, memory, and the like, and a bus for enabling free connection among the logical elements, and processes data through a pipeline system according to the connection among the logical elements. Further, an implemented logic of this reconfigurable circuit can be freely reconfigured by changing the connection among the logical elements. Accordingly, the processor of the computer system realizes high-speed processing performance and high versatility.
However, the processor of the ALU system performs data computing through the pipeline system, so when the implemented logic of the reconfigurable circuit is updated, data flowing through the circuit is destroyed, causing a problem of a loss of input data.
Thus, a system that changes the implemented logic of the reconfigurable circuit without losing the input data has been proposed. There have been proposed a system for changing two reconfigurable circuits, that is, currently used and spare reconfigurable circuits by a switch to realize the changing of the implemented logic without any data loss, a system for accumulating input data through an input buffer to change the implemented logic at a point when there is no more data left in the reconfigurable circuit, and the like (refer to “Studies on Uninterruptible Reconfiguration Method in Packet Transfer Processing” by Hidenori Kai and Hiroki Yamada, Society Conference of the Institute of Electronics, Information and Communication Engineers, B-6-150, September 2003).
SUMMARY OF THE INVENTION
However, problems as described below have been inevitable in the conventional DRP and the DRP for switching the currently used and spare circuits.
In a case of the processor for switching the two currently used and spare reconfigurable circuits through the switch to realize changing of the implemented logic without any data loss, a number of necessary reconfigurable circuits is doubled, causing high implementing costs.
In a case of the conventional DRP employing a system for accumulating the input data by the input buffer to change the implemented logic at a point when there is no more data left in the reconfigurable circuit, data inputting and computing processings are stopped while the input data are accumulated in the buffer, causing deterioration of data computing processing performance when the implemented logic is changed.
This invention has been made to solve the above-mentioned problems, and it is an object of this invention to provide a reconfigurable processor and a reconfigurable apparatus capable of realizing logic changing without any loss of input data and without any deterioration of the data computing processing performance.
The reconfigurable processor and apparatus of this invention are each configured as follows to realize the logic changing without any loss of input data and without any deterioration of the data computing processing performance.
According to an aspect of this invention, there is provided a reconfigurable processor/apparatus equipped with at least one reconfigurable computing means capable of implementing optional logics, including: an input data dividing unit for dividing data input to one of the processor and apparatus to generate and output a plurality of pieces of divided data; at least one retiming output buffer for temporarily storing data output from the reconfigurable computing means and the input data dividing unit to output the data by matched timing; an output data binding unit for binding the data read from the retiming output buffer by the matched timing to output the data to an outside of the processor; and means for changing a logic implemented in the reconfigurable computing means within a time period during which computing processing is not executed by the reconfigurable computing means.
Further, according to another aspect of this invention, there is provided a reconfigurable processor/apparatus, including: an input data dividing unit for dividing data to be input to generate a plurality of pieces of divided data, and outputting a part of the plurality of pieces of divided data to one of the reconfigurable computing means; a processed data selection unit for performing one of selecting and binding of at least one piece of data from data output from the input data dividing unit and the reconfigurable computing means to output processed data; at least one retiming selection buffer for temporarily storing data input to the processed data selection unit to output the data by matched timing; an output data binding unit for binding the output data of the reconfigurable computing means, the input data dividing unit, and the processed data selection unit to output the data to an outside of the processor; at least one retiming output buffer for temporarily storing data input to the output data binding unit to output the data by the matched timing; and means for freely interconnecting the reconfigurable computing means in one of series and parallel.
In addition, the reconfigurable processor/apparatus further includes a reconfiguring-of-logic judgment unit in a stage before the input data dividing unit, for permitting logic changing when a format length of the input data exceeds a predesignated value when compared and when there is no data input for a certain period of time.
Further, the reconfigurable processor/apparatus further includes at least one configuration control unit; at least one configuration buffer for each of the configuration control units; and means for permitting the configuration control unit to implement a logic designated by configuration information prestored in the configuration buffer in the reconfigurable computing means.
The reconfigurable processor or apparatus for enabling logic changing without any loss of input data and without any deterioration of data computing processing performance is realized, which is impossible with the conventional reconfigurable processor or apparatus.
According to this invention, the processor or the apparatus is realized by a system of distributing data only necessary for computing among the input data to the reconfigurable computing means, and a system of changing the implemented logic of the reconfigurable computing means by using non-computing time generated in the reconfigurable computing means when data unnecessary for the computing is being input.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing a reconfigurable processor equipped with n reconfigurable circuits according to a first embodiment of this invention.
FIG. 2 is a block diagram showing a reconfigurable apparatus equipped with n reconfigurable processors according to a second embodiment of this invention.
FIG. 3 is a block diagram showing an example of an ALU type reconfigurable circuit according to the first embodiment of this invention.
FIG. 4 is a block diagram showing an example of an AND-OR/LUT type reconfigurable circuit according to the first embodiment of this invention.
FIG. 5 is a block diagram showing an example of a multi-CPU type reconfigurable circuit according to the first embodiment of this invention.
FIG. 6 is a block diagram showing a reconfigurable processor equipped with two reconfigurable circuits according to a third embodiment of this invention.
FIG. 7 is a block diagram showing a reconfigurable apparatus equipped with two reconfigurable processors according to a fourth embodiment of this invention.
FIG. 8 is a block diagram showing the reconfigurable processor equipped with an illegal communication defense function according to the third embodiment of this invention.
FIG. 9 is a block diagram showing the reconfigurable apparatus equipped with an illegal communication defense function according to the fourth embodiment of this invention.
FIG. 10 is a block diagram showing an illegal communication defense apparatus equipped with a reconfigurable processor implemented unit for executing illegal communication defense processing according to a fifth embodiment of this invention.
FIG. 11 is a block diagram showing a communication apparatus equipped with a reconfigurable processor implemented unit for executing illegal communication defense processing and a packet transfer unit according to the fifth embodiment of this invention.
FIG. 12 is a block diagram showing the communication apparatus equipped with the reconfigurable processor implemented unit for executing the illegal communication defense processing, the packet transfer unit, and a switching unit according to the fifth embodiment of this invention.
FIG. 13 is a block diagram showing the communication apparatus equipped with the reconfigurable processor implemented unit for executing the illegal communication defense processing for each of the packet transfer units, and the switching unit according to the fifth embodiment of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
Referring to FIGS. 1 and 3 to 5 , an operation of a first embodiment of this invention will be described in detail.
FIG. 1 is a block diagram showing a reconfigurable processor 100 of this invention. The reconfigurable processor 100 includes a reconfiguring-of-logic judgment unit 139 for comparing a format length of input data 138 with a predesignated value, or data non-input time with a predesignated value, an input data dividing unit 110 for dividing data 140 identical to the input data 138 to output the divided data, a reconfigurable circuit 130 -i (i=1 to n) in which an optional logic can be implemented, a processed data selection unit 111 -i (i=2 to n) for selecting and synthesizing a plurality of pieces of data being processed to output new data, retiming selection buffers 190 -i−j (i=1 to n−1, j=1 to n) and 191 -i (i=1 to n−1) for providing predesignated delays to divided data 141 - 1 −i (i=1 to n) output from the input data dividing unit 110 , selected data 141 -i−j (i=2 to n, j=1 to n) output from the processed data selection unit 111 -i, or computing result data 144 -i (i=1 to n−1) output from the reconfigurable circuit 130 -i to output the data to the processed data selection unit 111 -i, an output data binding unit 112 for synthesizing the processed data to output final data 151 to the outside of the processor, retiming output buffers 123 -i (i=1 to n), 122 , and 124 for outputting divided data 152 output from the input data dividing unit 110 , selected data 141 -n−j (=1 to n) output from the processed data selection unit n 111 -n, or computing result data 144 -n output from the reconfigurable circuit 130 -n to the output data binding unit by matched timing, a configuration control unit 113 -i (i=1 to n) for rewriting an implemented logic of each reconfigurable circuit 130 -i, and a configuration buffer 121 -i−k (i=1 to n, k=1 to m) for storing configuration information designating an implemented logic.
FIGS. 3 to 5 are exemplary block diagrams of the reconfigurable circuits. FIG. 3 shows an example of a ALU type reconfigurable circuit 300 , FIG. 4 shows an example of an AND-OR/LUT type reconfigurable circuit 400 , and FIG. 5 shows an example of a multi-CPU type reconfigurable circuit 500 .
Next, FIGS. 1 and 3 to 5 will be described in detail.
The reconfigurable processor 100 of FIG. 1 receives the data 138 continuously flowing in from the outside of the processor to execute various processing operations therein, and outputs a processing result as final data 151 to the outside of the processor.
The reconfiguring-of-logic judgment unit 139 receives the data 138 input by a certain format from the outside of the processor to judge whether a format length is larger than a predesignated value. When the format length is larger, the reconfiguring-of-logic judgment unit 139 transmits a command 179 for permitting changing of an implemented logic of the reconfigurable circuit. Alternatively, the reconfiguring-of-logic judgment unit 139 transmits the command 179 for permitting changing of the implemented logic of the reconfigurable circuit when data non-input time exceeds a predetermined period of time. The input data 138 is output as data 140 after a predesignated delay is generated.
The input data dividing unit 110 divides the input data 140 . There are three types of divided data, i.e., divided data 142 - 1 output to the reconfigurable circuit i 130 - 1 , divided data 141 - 1 −i (i=1 to n) output to the processed data selection unit 111 - 2 , and divided data 152 output to the output data binding unit 112 . Dividing timing is designated by a preset bit pattern, and a dividing range is set within a preset bit range and a preset clock range. For example, when real-time data 140 is input to the reconfigurable processor 100 by 35 bits per clock, dividing timing is designated to be a 7-th clock from when a bit pattern of higher order of 33 to 35 bits of the input data becomes “101”, and a dividing range is designated to be 3 clocks of lower order of 1 to 32 bits of the input data.
The reconfigurable circuit i 130 -i (i=1 to n) processes data 142 -i (i=1 to n) input from the outside of the circuit according to a pre-implemented logic, and outputs a processing result as computing result data 144 -i (i=1 to n) to the outside of the circuit. As shown in FIGS. 3 to 5 , the inside of the circuit has a structure in which a plurality of functional blocks are interconnected through a plurality of buses.
The ALU type reconfigurable circuit 300 of FIG. 3 includes ALU type functional blocks. Each functional block has a relatively large bit input/output such as 8, 16, or 32 bits, and includes EXE blocks 311 to 315 for performing predesignated arithmetic operations, CNT blocks 321 to 325 each having a counter function, RAM blocks 331 to 335 for performing data storage, DLE blocks 341 to 345 for delaying input data by designated clocks to output the data, IOB blocks 351 to 355 for inputting/outputting data with respect to the outside of the circuit, and the like. Outputs and inputs of the functional blocks can be freely connected by cross bar type switches 361 to 365 and 371 to 375 .
The AND-OR/LUT type reconfigurable circuit 400 of FIG. 4 includes AND-OR/LUT type functional blocks. Each functional block has a relatively small bit input/output such as 1, 2, or 4 bits, and includes CLB blocks 411 to 415 , 421 to 425 , 431 to 435 , and 441 to 445 for outputting predesignated bit patterns according to input bit patterns, 10 B blocks 451 to 455 for inputting/outputting data with respect to the outside of the circuit, and the like. Outputs and inputs of the functional blocks can be freely connected through cross bar type switches 461 to 465 and 471 to 475 .
The multi-CPU type reconfigurable circuit 500 of FIG. 5 includes CPU type functional blocks. Each functional block has a relatively large bit input/output such as 8, 16, or 32 bits, and includes CPU blocks 511 to 515 , 521 to 525 , and 531 to 535 for performing various arithmetic operations according to predesignated commands, RAM blocks 531 to 535 for storing data, IOB blocks 551 to 555 for inputting/outputting data with respect to the outside of the circuit, and the like. Outputs and inputs of the functional blocks can be freely connected through cross bar type switches 561 to 565 and 571 to 575 .
The processed data selection unit i 111 -i (i=2 to n) selects one or more pieces of preset data from a plurality of pieces of data 154 -i−j (i=1 to n−1, j=1 to n), 155 -i (i=1 to n−1) read from the retiming selection buffers by matched timing, and binds a preset bit range and a preset clock range of the plurality of pieces of selected data in the timing of a preset bit pattern to output the selected data to the outside of the processor. There are two types of selected data to be output, i.e., selected data 142 -i (i=2 to n) output to the reconfigurable circuit i 130 -i (i=1 to n), and selected data 141 -i−j (i=2 to n, j=1 to n) output to the others. The input data 155 -i is directly output as selected data 141 −(i+1)-i.
The retiming selection buffer 190 -i−j (i=1 to n−1, j=1 to n) stores the divided data 141 -i−j (1=1 to n) from the input data dividing unit 110 or the selected data 141 -i−j (i=2 to n−1, j=1 to n) from the processed data selection unit i 111 -i (i=2 to n−1). The retiming selection buffer 191 -i (i=1 to n−1) stores the computing result data 144 -i (i=1 to n−1) from the reconfigurable circuit i 130 -i (i=1 to n−1). The stored data are read after timings are matched by the processed data selection unit i 111 -i (i=2 to n).
The output data binding unit 112 selects one or more pieces of preset data from the plurality of pieces of data 153 , 145 -i (i=1 to n), and 150 read from the retiming output buffer by the matched timing, and binds a preset bit range and a preset clock range of the plurality of pieces of selected data by the timing of a preset bit pattern to output final data 151 to the outside of the processor.
The retiming output buffer 122 stores the divided data 152 from the input data dividing unit 110 . The output buffer 124 stores computing result data 144 -n from the reconfigurable circuit n 130 -n. The retiming output buffer 123 -i (i=1 to n) stores the selected data 141 -n−j (=1 to n) from the processed data selection unit n 111 -n. The stored data are read after timings are matched by the output data binding unit 112 .
Upon reception of a configuration change command 181 -i (i=1 to n) containing a reconfigurable circuit number and a configuration information number from the communication unit 101 outside the processor, the configuration control unit 113 -i (i=1 to n) reads configuration information 161 -i−j (i=1 to n, j=1 to m) matched with the configuration information number in the configuration change command 181 -i (i=1 to n) from the configuration buffer 121 -i−j (i=1 to n, j=1 to m) disposed in each configuration control unit 113 -i, and sends a rewrite command 162 -i−j (i=1 to n, j=1 to m) of an implemented logic designated by configuration information 161 -i−j to the reconfigurable circuit i 130 -i (i=1 to n) matched with the reconfigurable circuit number. The reconfigurable circuit i 130 -i rewrites the implemented logic according to the rewrite command 162 -i−j.
The configuration change command 181 -i (i=1 to n) may contain the number of writable clocks. In this case, the configuration control unit 113 -i (i=1 to n) outputs the rewrite command 162 -i−j of the implemented logic after a passage of the number of writable clocks after reception of the command 179 to permit changing of the implemented logic of the reconfiguring-of-logic judgment unit 139 .
The reconfigurable processor 100 sets information 180 on dividing timing and a dividing range received from the communication unit 101 outside the processor in the input data dividing unit 110 , sets information 184 on selected data, binding timing, and a binding range received from the communication unit 101 outside the processor in the output data binding unit 112 , sets information 182 -i (i=2 to n) on selected data, binding timing, and a binding range received from the communication unit 101 outside the processor in the processed data selection unit 111 -i (i=2 to n), and sets information 179 on designated format length and data non-input continuance time received from the communication unit 101 outside the processor in the reconfiguring-of-logic judgment unit 139 .
The reconfigurable processor 100 stores the configuration information 160 -i (i=1 to n) received from the communication unit 101 outside the processor in the configuration buffer 121 -i−j.
In the memory 132 -i (i=1 to n) incorporated in the reconfigurable circuit i 130 -i of the reconfigurable processor 100 , direct reading/writing is executed with respect to the communication unit 101 outside the processor. During reading, a read command 186 -i (i=1 to n) containing an address number is transmitted from the communication unit 101 to the memory, and read data 186 -i is returned from the memory 132 -i. During writing, a write command 186 -i containing an address number and write data is transmitted from the communication unit 101 to the memory.
Information transfer between the communication unit 101 and the reconfigurable processor 100 is carried out according to a command 185 from the terminal 102 to the communication unit 101 .
The reconfigurable processor 100 includes the reconfigurable circuits i 130 -i (i=1 to n), the input data dividing unit 110 , the retiming output buffers 123 -i, 122 , and 124 , and the output data binding unit 112 . Accordingly, by distributing only the data necessary for computing among the input data to the reconfigurable circuit while not distributing the data when data unnecessary for computing is being input, the means for changing the implemented logic of the reconfigurable circuit is realized by using the non-computing time generated in the reconfigurable circuit. Hence, it is possible to realize the reconfigurable processor for enabling logic changing without any loss of input data and without any deterioration of data computing processing performance, which is impossible with the conventional reconfigurable processor or apparatus.
The reconfigurable processor 100 includes the processed data selection unit i 111 -i and the retiming selection buffers 190 -i−j and 191 -i. Hence, the plurality of reconfigurable circuits can be connected in series or in parallel.
The reconfigurable processor 100 includes the configuration control unit 113 -i (i=1 to n) as described above and the configuration buffer 121 -i−j (i=to n, j=1 to m). Hence, it is possible to implement a logic designated by configuration information prestored in the configuration buffer in each configurable circuit.
Further, the reconfigurable processor 100 includes the memory 132 -i (i=1 to n) described above. Hence, it is possible to directly read/write data with respect to the memory within the processor from the outside of the processor.
Second Embodiment
Referring to FIG. 2 , an operation of this invention will be described in detail.
FIG. 2 is a block diagram showing a reconfigurable apparatus 200 of this invention. The reconfigurable apparatus 200 includes a reconfiguring-of-logic judgment unit 239 for comparing a format length of input data 238 with a predesignated value or data non-input time with a predesignated value, an input data dividing unit 210 for dividing data 240 identical to the input data 238 to output the divided data, a reconfigurable processor 230 -i (i=1 to n) in which an optional logic can be implemented, a processed data selection unit 211 -i (i=2 to n) for selecting and synthesizing a plurality of pieces of data being processed to output new data, retiming selection buffers 290 -i−j (i=1 to n−1, j=1 to n) and 291 -i (i=1 to n−1) for providing predesignated delays to divided data 241 - 1 −i (i=1 to n) output from the input data dividing unit 210 , selected data 241 -i−j (i=2 to n, j=1 to n) output from the processed data selection unit 211 -i, or computing result data 244 -i (i=1 to n−1) output from the reconfigurable processor 230 -i to output the data to the processed data selection unit 211 -i, an output data binding unit 212 for synthesizing the processed data to output final data 251 to the outside of the apparatus, retiming output buffers 223 -i (i=1 to n), 222 , and 224 for outputting divided data 252 output from the input data dividing unit 210 , selected data 241 -n−j (=1 to n) output from the processed data selection unit n 211 -n, or computing result data 244 -n output from the reconfigurable processor 230 -n to the output data binding unit by matched timing, a configuration control unit 213 -i (i=1 to n) for rewriting an implemented logic of each reconfigurable processor 230 -i, and a configuration buffer 221 -i−k (i=1 to n, k=1 to m) for storing configuration information designating an implemented logic.
Next, FIG. 2 will be described in detail.
The reconfigurable apparatus 200 of FIG. 2 receives the data 238 continuously flowing in from the outside of the apparatus to execute various processing operations therein, and outputs a processing result as final data 251 to the outside of the apparatus.
The reconfiguring-of-logic judgment unit 239 receives the data 238 input by a certain format from the outside of the apparatus to judge whether a format length is larger than a predesignated value. When the format length is larger, the reconfiguring-of-logic judgment unit 239 transmits a command 279 for permitting changing of an implemented logic of the reconfigurable processor. Alternatively, the reconfiguring-of-logic judgment unit 239 transmits the command 279 for permitting changing of the implemented logic of the reconfigurable circuit when data non-input time exceeds a predetermined period of time. The input data 238 is output as data 240 after a predesignated delay is generated.
The input data dividing unit 210 divides the input data 240 . There are three types of divided data, i.e., divided data 242 - 1 output to the reconfigurable processor 1 230 - 1 , divided data 241 - 1 −i (i=1 to n) output to the processed data selection unit 211 - 2 , and divided data 252 output to the output data binding unit 212 . Dividing timing is designated by a preset bit pattern, and a dividing range is set within a preset bit range and a preset clock range. For example, when real-time data 240 is input to the reconfigurable apparatus 200 by 35 bits per clock, dividing timing is designated to be a 7-th clock from when a bit pattern of higher order of 33 to 35 bits of the input data becomes “101”, and a dividing range is designated to be 3 clocks of lower order of 1 to 32 bits of the input data.
The reconfigurable processor i 230 -i (i=1 to n) processes data 242 -i (i=1 to n) input from the outside of the processor according to a pre-implemented logic, and outputs a processing result as computing result data 244 -i (i=1 to n) to the outside of the processor.
The processed data selection unit i 211 -i (i=2 to n) selects one or more pieces of preset data from a plurality of pieces of data 254 -i−j (i=1 to n−1, j=1 to n) and 255 -i (i=1 to n−1) read from the retiming selection buffers by matched timing, and binds a preset bit range and a preset clock range of the plurality of pieces of selected data by timing of a preset bit pattern to output the selected data to the outside of the apparatus. There are two types of selected data to be output, i.e., selected data 242 -i (i=2 to n) output to the reconfigurable processor i 230 -i (i=2 to n), and selected data 241 -i−j (i=2 to n, j=1 to n) output to the others. The input data 255 -i is directly output as selected data 241 -(i+1)−i.
The retiming selection buffer 290 -i−j (i=1 to n−1, j=1 to n) stores the divided data 24 - 1 −j (=1 to n) from the input data dividing unit 210 or the selected data 241 -i−j (i=2 to n−1, j=1 to n) from the processed data selection unit i 211 -i (i=2 to n−1). The retiming selection buffer 291 -i (i=1 to n−1) stores the computing result data 244 -i (i=1 to n−1) from the reconfigurable processor i 230 -i (i=1 to n−1). The stored data are read after timings are matched by the processed data selection unit i 211 -i (i=2 to n).
The output data binding unit 212 selects one or more pieces of preset data from the plurality of pieces of data 253 , 245 -i (i=1 to n), and 250 read from the retiming output buffer by the matched timing, and binds a preset bit range and a preset clock range of the plurality of pieces of selected data by the timing of a preset bit pattern to output final data 251 to the outside of the apparatus.
The retiming output buffer 222 stores the divided data 252 from the input data dividing unit 210 . The output buffer 224 stores computing result data 244 -n from the reconfigurable processor n 230 -n. The retiming output buffer 223 -i (i=1 to n) stores the selected data 241 -n−j (j=1 to n) from the processed data selection unit n 211 -n. The stored data are read after timings are matched by the output data binding unit 212 .
Upon reception of a configuration change command 281 -i (i=1 to n) containing a reconfigurable processor number and a configuration information number from a communication unit 201 outside the apparatus, the configuration control unit 213 -i (i=1 to n) reads configuration information 261 -i−j (i=1 to n, j=1 to m) matched with the configuration information number of the configuration change command 281 -i (i=1 to n) from the configuration buffer 221 -i−j (i=1 to n, j=1 to m) disposed in each configuration control unit 213 -i, and sends a rewrite command 262 -i−j (i=1 to n, j=1 to m) of an implemented logic designated by configuration information 261 -i−j to the reconfigurable processor i 230 -i (i=1 to n) matched with the reconfigurable processor number. The reconfigurable processor i 230 -i rewrites the implemented logic according to the rewrite command 262 -i−j.
The configuration change command 281 -i (i=1 to n) may contain the number of writable clocks. In this case, the configuration control unit 213 -i (i=1 to n) outputs the rewrite command 262 -i−j of the implemented logic after a passage of the number of writable clocks after reception of the command 279 to permit changing of the implemented logic of the reconfiguring-of-logic judgment unit 239 .
The reconfigurable apparatus 200 sets information 280 on dividing timing and a dividing range received from the communication unit 201 outside the apparatus in the input data dividing unit 210 , sets information 284 on selected data, binding timing, and a binding range received from the communication unit 201 outside the apparatus in the output data binding unit 212 , sets information 282 -i (i=2 to n) on selected data, binding timing, and a binding range received from the communication unit 201 outside the apparatus in the processed data selection unit 211 -i (i=2 to n), and sets information 279 on designated format length and data non-input continuance time received from the communication unit 201 outside the apparatus in the reconfiguring-of-logic judgment unit 239 .
The reconfigurable apparatus 200 stores the configuration information 260 -i (i=1 to n) received from the communication unit 201 outside the apparatus in the configuration buffer 221 -i−j.
In the memory 232 -i (i=1 to n) incorporated in the reconfigurable processor i 230 -i of the reconfigurable apparatus 200 , direct reading/writing is executed with respect to the communication unit 201 outside the apparatus. During reading, a read command 286 -i (i=1 to n) containing an address number is transmitted from the communication unit 201 to the memory, and read data 286 -i is returned from the memory 232 -i. During writing, a write command 286 -i containing an address number and write data is transmitted from the communication unit 201 to the memory.
Information transfer between the communication unit 201 and the reconfigurable apparatus 200 is carried out according to a command 285 from the terminal 202 to the communication unit 201 .
The reconfigurable apparatus 200 includes the reconfigurable processor i 230 -i (i=1 to n) described above, the input data dividing unit 210 , the retiming output buffers 223 -i, 222 , and 224 , and the output data binding unit 212 . Accordingly, by distributing only the data necessary for computing among the input data to the reconfigurable processor while not distributing the data when data unnecessary for computing is being input, the means for changing the implemented logic of the reconfigurable processor is realized by using the non-computing time generated in the reconfigurable processor. Hence, it is possible to realize the reconfigurable apparatus for enabling logic changing without any loss of input data and without any deterioration of data computing processing performance, which is impossible with the conventional reconfigurable processor or apparatus.
The reconfigurable apparatus 200 includes the processed data selection unit i 211 -i and the retiming selection buffers 290 -i−j and 291 -i. Hence, the plurality of reconfigurable processors can be connected in series or in parallel.
The reconfigurable apparatus 200 includes the configuration control unit 213 -i (i=1 to n) described above and the configuration buffer 221 -i−j (i=1 to n, j=1 to m). Hence, it is possible to implement a logic designated by configuration information prestored in the configuration buffer in each configurable processor.
Further, the reconfigurable apparatus 200 includes the memory 232 -i (i=1 to n). Hence, it is possible to directly read/write data with respect to the memory within the apparatus from the outside of the apparatus.
Third Embodiment
Referring to FIGS. 6 and 8 , an operation of this invention will be described in detail.
FIG. 6 is a block diagram of a reconfigurable processor 600 when n=2 is set in the reconfigurable processor 100 of FIG. 1 . A block indicated by reference numerals of 600 's of FIG. 6 has the same function as that of a block indicated by reference numerals of 100 's of FIG. 1 .
FIG. 8 is a block diagram when the reconfigurable processor 600 of FIG. 6 is used as an illegal communication defense reconfigurable processor 800 in a network. An illegal communication judgment circuit 834 for judging an abnormality type for each packet is implemented in a first reconfigurable circuit 1 830 - 1 , and a communication statistics table 835 is implemented in an incorporated memory 832 - 1 . An illegal communication removal circuit 836 for judging passing/discarding of each packet based on a judging result of the abnormality type is implemented in a second reconfigurable circuit 2 830 - 2 . A session table 837 is implemented in an incorporated memory 832 - 2 .
FIGS. 6 and 8 will be described in detail below.
The reconfigurable processor 600 of FIG. 6 divides input data 640 in an input data dividing unit 610 . When the input data dividing unit 610 is set to output divided data 642 - 1 to a reconfigurable circuit 1 630 - 1 and divided data 641 - 1 −i (i=1, 2) to a processed data selection unit 611 - 2 , and the processed data selection unit 611 - 2 is set to output input data 654 - 1 −i (i=1, 2) as selected data 642 - 2 and input data 655 - 1 as selected data 641 - 2 -i (i=1, 2), the two reconfigurable circuits are connected in parallel. On the other hand, when the input data dividing unit 610 is set to output only the divided data 642 - 1 to the reconfigurable circuit 1 630 - 1 , and the processed data selection unit 611 - 2 is set to output the input data 655 - 1 as selected data 642 - 2 , the two reconfigurable circuits are connected in series.
The illegal communication defense reconfigurable processor 800 of FIG. 8 is a processor obtained by including an illegal communication defense function in the reconfigurable processor 600 of FIG. 6 . The illegal communication defense function analyzes packets flowing through a communication network to detect and remove excessive load communications such as peer to peer (P2P) which causes communication faults, or various abnormal communications such as illegal communications executed to attack a personal computer (PC), a router, or a server, e.g., Worm, denial of service (DoS), or distributed denial of service (DDoS). A reconfiguring-of-logic judgment unit 839 judges a packet length as a format length when used for the network. A packet length of an IP header field in the received packet is read to be compared with a predesignated packet length. For example, presuming that a predesignated packet length is 1000 bytes, when a packet whose length is equal to or more than 1000 bytes arrives, a command 879 for changing an implemented logic of the reconfigurable processor is output.
Upon reception of packet data flowing through the network as data 840 , the input data dividing unit 810 outputs a part of the packet data as divided data 842 - 1 to the first reconfigurable circuit 1 830 - 1 . The input data dividing unit 810 also outputs a part of the packet data as divided data 841 - 1 - 1 to a processed data selection unit 811 - 2 , and all pieces of packet data as divided data 852 to an output data binding unit 812 .
For example, the divided data 842 - 1 output to the first reconfigurable circuit 1 830 - 1 contains information such as a transmission source IP address, a destination IP address, a transmission source port number, a destination port number, a TCP flag number, a protocol number, or a packet length described in an IP header or a TCP/UDP header inside a packet. The divided data 841 - 1 - 1 output to the processed data selection unit 811 - 2 contains information such as the transmission source IP address, the destination IP address, the transmission source port number, the destination port number, the TCP flag number, the protocol number, the packet length, a sequence number, or an ACK number described in the IP header or the TCP/UDP header inside the packet.
The illegal communication judgment circuit 834 implemented in the first reconfigurable circuit 1 830 - 1 analyzes a part of packet data output from the input data dividing unit 810 , and stores an analyzing result as communication statistics information in the communication statistics table 835 built in the memory 832 - 1 . The communication statistics information stored in the communication statistics table 835 contains a communication definition such as a transmission source IP address, a destination IP address, a transmission source port number, a destination port number, or a TCP flag number, a packet integrated number matched with the communication definition, and the like.
The illegal communication judgment circuit 834 judges whether a received packet is normal/abnormal based on the communication statistics information stored in the communication statistics table 835 . If the packet is judged to be abnormal, a type of the abnormality is judged. Results of judging normality/abnormality and an abnormality type are output as computing result data 844 - 1 to the processed data selection unit 811 - 2 .
The processed data selection unit 811 - 2 outputs a part of the received packet data and the judging results of normality/abnormality and the abnormality type as selected data 842 - 2 to the second reconfigurable circuit 2 830 - 2 .
The illegal communication removal circuit 836 implemented in the second reconfigurable circuit 2 830 - 2 analyzes a part of the packet data output from the processed data selection unit 811 - 2 according to the judging results of the normality/abnormality and the abnormality type output from the processed data selection unit 811 - 2 , and stores an analyzing result as session information in the session table 837 built in the memory 832 - 2 . The session information stored in the session table 837 contains a communication definition such as a transmission source IP address, a destination IP address, a transmission source port number, or a destination port number, a packet integrated number matched with the communication definition, presence/absence of a connection requested packet, presence/absence of a response requested packet, presence/absence of a response packet, and the like.
The illegal communication removal circuit 836 judges whether all pieces of the received packet data are to be passed/discarded based on the session information stored in the session table 837 . A passing/discarding judging result is output as computing result data 844 - 2 .
The output data binding unit 812 outputs all pieces of the packet data received from the input data dividing unit 810 only when the received computing result data 844 - 2 has a bit sequence expected when a judging result indicates that the packet data is to be passed. Accordingly, when it is judged that the packet data is to be discarded, outputting of the packet data is stopped.
The illegal communication defense reconfigurable processor 800 is realized by including the reconfigurable circuit 1 830 - 1 having the illegal communication judgment circuit 834 and the reconfigurable circuit 2 830 - 2 having the illegal communication removal circuit 836 . The illegal communication judgment circuit 834 implemented in the reconfigurable circuit 1 830 - 1 and the illegal communication removal circuit 836 implemented in the reconfigurable circuit 2 830 - 2 can minimize and separately receive data necessary for computing. Thus, for example, when time from a reception start of a 1500 byte-length packet to an end is 150 clocks, time from a reception start of data (20 bytes of 1500 bytes) needed by the illegal communication judgment circuit to an end is 2 clocks, and circuit passing time from inputting of data to outputting of a judging result is 100 clocks, non-computing time of 48 clocks is generated in the reconfigurable circuit 1 . By using such the non-computing time generated during long packet inputting to update an algorithm implemented in the reconfigurable circuit 1 , it is possible to realize uninterruptible algorithm updating without any throughput deterioration.
Fourth Embodiment
Referring to FIGS. 7 and 9 , an operation of this invention will be described in detail.
FIG. 7 is a block diagram of a reconfigurable apparatus 700 when n=2 is set in the reconfigurable apparatus 200 of FIG. 2 . A block indicated by reference numerals of 700 's of FIG. 7 has the same function as that of a block indicated by reference numerals of 200's of FIG. 2 .
FIG. 9 is a block diagram showing a case where the reconfigurable apparatus 700 of FIG. 7 is used as an illegal communication defense reconfigurable apparatus 900 . An illegal communication judgment circuit 934 for judging an abnormality type for each packet is implemented in a first reconfigurable processor 1 930 - 1 , and a communication statistics table 935 is implemented in an incorporated memory 932 - 1 . An illegal communication removal circuit 936 for judging passing/discarding of each packet based on a judging result of the abnormality type is implemented in a second reconfigurable processor 2 930 - 2 . A session table 937 is implemented in an incorporated memory 932 - 2 .
FIGS. 7 and 9 will be described in detail below.
The reconfigurable apparatus 700 of FIG. 7 divides input data 740 in an input data dividing unit 710 . When the input data dividing unit 710 is set to output divided data 742 - 1 to a reconfigurable processor 1 730 - 1 and divided data 741 - 1 −i (i=1, 2) to a processed data selection unit 711 - 2 , and the processed data selection unit 711 - 2 is set to output input data 754 - 1 −i(i=1, 2) as selected data 742 - 2 and input data 755 - 1 as selected data 741 - 2 -i(i=1, 2), the two reconfigurable processors are connected in parallel. On the other hand, when the input data dividing unit 710 is set to output only the divided data 742 - 1 to the reconfigurable processor 1 730 - 1 , and the processed data selection unit 711 - 2 is set to output the input data 755 - 1 as selected data 742 - 2 , the two reconfigurable processors are connected in series.
The illegal communication defense reconfigurable apparatus 900 of FIG. 9 is an apparatus obtained by including an illegal communication defense function in the reconfigurable apparatus 700 of FIG. 7 .
A reconfiguring-of-logic judgment unit 939 judges a packet length as a format length when used for a network. A packet length of an IP header field in the received packet is read to be compared with a predesignated packet length. For example, presuming that a predesignated packet length is 1000 bytes, when a packet whose length is equal to or more than 1000 bytes arrives, a command 979 for changing an implemented logic of the reconfigurable processor is output.
Upon reception of packet data flowing through the network as data 940 , the input data dividing unit 910 outputs a part of the packet data as divided data 942 - 1 to the first reconfigurable processor 1 930 - 1 . The input data dividing unit 910 also outputs a part of the packet data as divided data 941 - 1 - 1 to a processed data selection unit 911 - 2 , and all pieces of packet data as divided data 952 to an output data binding unit 912 .
The divided data 942 - 1 output to the first reconfigurable processor 1 930 - 1 contains, for example, information such as a transmission source IP address, a destination IP address, a transmission source port number, a destination port number, a TCP flag number, a protocol number, or a packet length described in an IP header or a TCP/UDP header inside a packet. The divided data 941 - 1 - 1 output to the processed data selection unit 911 - 2 contains information such as the transmission source IP address, the destination IP address, the transmission source port number, the destination port number, the TCP flag number, the protocol number, the packet length, a sequence number, or an ACK number described in the IP header or the TCP/UDP header inside the packet.
The illegal communication judgment circuit 934 implemented in the first reconfigurable processor 1 930 - 1 analyzes a part of packet data output from the input data dividing unit 910 , and stores an analyzing result as communication statistics information in a communication statistics table 935 built in the memory 932 - 1 . The communication statistics information stored in the communication statistics table 935 contains a communication definition such as a transmission source IP address, a destination IP address, a transmission source port number, a destination port number, or a TCP flag number, a packet integrated number matched with the communication definition, and the like.
The illegal communication judgment circuit 934 judges whether a received packet is normal/abnormal based on the communication statistics information stored in the communication statistics table 935 . If the packet is judged to be abnormal, a type of the abnormality is judged. Results of judging normality/abnormality and an abnormality type are output as computing result data 944 - 1 to the processed data selection unit 911 - 2 .
The processed data selection unit 911 - 2 outputs a part of the received packet data and the judging results of normality/abnormality and the abnormality type as selected data 942 - 2 to the second reconfigurable processor 2 930 - 2 .
The illegal communication removal circuit 936 implemented in the second reconfigurable processor 2 930 - 2 analyzes a part of the packet data output from the processed data selection unit 911 - 2 according to the judging results of the normality/abnormality and the abnormality type output from the processed data selection unit 911 - 2 , and stores an analyzing result as session information in a session table 937 built in the memory 932 - 2 . The session information stored in the session table 937 contains a communication definition such as a transmission source IP address, a destination IP address, a transmission source port number, or a destination port number, a packet integrated number matched with the communication definition, presence/absence of a connection requested packet, presence/absence of a response requested packet, presence/absence of a response packet, and the like.
The illegal communication removal circuit 936 judges whether all the pieces of received packet data are to be passed/discarded based on the session information stored in the session table 937 . A passing/discarding judging result is output as computing result data 944 - 2 .
The output data binding unit 912 outputs all pieces of the packet data received from the input data dividing unit 910 only when the received computing result data 944 - 2 has a bit sequence expected when a judging result indicates that the packet data is to be passed. Accordingly, when it is judged that the packet data is to be discarded, outputting of the packet data is stopped.
The illegal communication defense reconfigurable apparatus 900 is realized by including the reconfigurable processor 1 930 - 1 having the illegal communication judgment circuit 934 and the reconfigurable processor 2 930 - 2 having the illegal communication removal circuit 936 as described above. The illegal communication judgment circuit 934 implemented in the reconfigurable processor 1 930 - 1 and the illegal communication removal circuit 936 implemented in the reconfigurable processor 2 930 - 2 can minimize and separately receive data necessary for computing. Thus, for example, when time from a reception start of a 1500 byte-length packet to an end is 150 clocks, time from a reception start of data (20 bytes of 1500 bytes) needed by the illegal communication judgment circuit to an end is 2 clocks, and circuit passing time from inputting of data to outputting of a judging result is 100 clocks, non-computing time of 48 clocks is generated in the reconfigurable circuit 1 . By using such the non-computing time generated during long packet inputting to update an algorithm implemented in the reconfigurable circuit 1 , it is possible to realize uninterruptible algorithm updating without any throughput deterioration.
Fifth Embodiment
FIGS. 10 to 13 each show an example where a reconfigurable processor implemented unit including the illegal communication defense reconfigurable processor 800 or the illegal communication defense reconfigurable apparatus 900 of this invention is used for communication.
FIG. 10 is a block diagram showing an illegal communication defense apparatus 1000 which includes the illegal communication defense reconfigurable processor 800 or the illegal communication defense reconfigurable apparatus 900 in a reconfigurable processor implemented unit 1020 , and two communication data input/output units 1010 and 1011 .
FIG. 11 is a block diagram showing a communication apparatus 1100 which includes the illegal communication defense reconfigurable processor 800 or the illegal communication defense reconfigurable apparatus 900 in a reconfigurable processor implemented unit 1140 , an illegal communication defense unit 1120 including the reconfigurable processor implemented unit 1140 , a packet transfer unit 1130 , and a communication data input/output unit 1132 −k (k=1 to m).
FIG. 12 is a block diagram showing a communication apparatus 1200 which includes the illegal communication defense reconfigurable processor 800 or the illegal communication defense reconfigurable apparatus 900 in a reconfigurable processor implemented unit 1240 , an illegal communication defense unit 1220 including the reconfigurable processor implemented unit 1240 , a switching unit 1210 , a packet transfer unit 1230 -i (i=1 to n), and a communication data input/output unit 1232 -i−k (i=1 to n, k=1 to m).
FIG. 13 is a block diagram showing a communication apparatus 1300 which includes the illegal communication defense reconfigurable processor 800 or the illegal communication defense reconfigurable apparatus 900 in a reconfigurable processor implemented unit 1340 -i (i=1 to n), an illegal communication defense unit 1320 -i (i=1 to n) including the reconfigurable processor implemented unit 1340 -i, a switching unit 1310 , a packet transfer unit 1330 -i (i=1 to n), and a communication data input/output unit 1332 -i−k (i=1 to n, k=1 to m).
FIGS. 10 to 13 will be described below in detail.
The illegal communication defense apparatus 1000 of FIG. 10 includes the two communication data input/output units 1010 and 1011 . Packet data input from each of the communication data input/output units 1010 and 1011 is subjected to illegal communication defense processing at the reconfigurable processor implemented unit 1020 , and the processed packet data is output from the other one of the communication data input/output units 1010 and 1011 .
The communication apparatus 1100 of FIG. 11 includes one or more communication data input/output units 1132 −k (k=1 to m). Packet data input from each communication data input/output unit 1132 −k is subjected to illegal communication defense processing at the reconfigurable processor implemented unit 1140 in the illegal communication defense unit 1120 , and the processed packet data is output through a communication data internal input/output unit 1121 −k (k=1 to m) to the packet transfer unit 1130 . The packet transfer unit 1130 transmits the received packet data to the communication data internal input/output unit 1121 −k set according to a destination IP address, a destination MAC address, a destination MPLS label number, or a destination VLAN number of the received packet data. The illegal communication defense unit 1120 outputs the packet received via the communication data internal input/output unit 1121 −k to the communication data input/output unit 1132 −k.
The communication apparatus 1200 of FIG. 12 includes a communication data input/output unit 1132 -i−k (i=1 to n, k=1 to m) for each packet transfer unit 1230 -i (i=1 to n). Packet data input from each communication data input/output unit 1232 -i−k to the packet transfer unit 1230 -i is output to the communication data input/output unit 1232 -i−k of the input destination packet transfer unit 1230 -i according to a destination IP address, a destination MAC address, a destination MPLS label number, or a destination VLAN number of the packet data, or output to the other packet transfer unit 1230 -i or the illegal communication defense unit 1220 via the communication data internal input/output unit 1231 -i (i=1 to n) and a switching unit 1210 . The packet data output to the illegal communication defense unit 1220 is subjected to illegal communication defense processing at the reconfigurable processor implemented unit 1240 in the illegal communication defense unit 1220 , and the processed packet data is output to the other packet transfer unit 1230 -i via the communication data internal input/output unit 1221 and the switching unit 1210 according to the destination IP address, the destination MAC address, the destination MPLS label number, or the destination VLAN number of the packet data. The packet transfer unit 1230 -i outputs the received packet data to the communication data input/output unit 1232 -i−k set according to the destination IP address, the destination MAC address, the destination MPLS label number, or the destination VLAN number of the packet data received from the switching unit 1210 .
The communication apparatus 1300 of FIG. 13 includes a communication data input/output unit 1332 -i−k (i=1 to n, k=1 to m) for each illegal communication defense unit 1320 -i (i=1 to n). Packet data input from each communication data input/output unit 1332 -i−k is subjected to illegal communication defense processing at the reconfigurable processor implemented unit 1340 -i in the illegal communication defense unit 1320 -i. The processed packet data is output through the communication data internal input/output unit 1321 -i−k (i=1 to n, k=1 to m) to the packet transfer unit 1330 -i (i=1 to n). The packet data output to the packet transfer unit 1330 -i is output to the communication data internal input/output unit 1321 -i−k connected to the input destination packet transfer unit 1330 -i according to a destination IP address, a destination MAC address, a destination MPLS label number, or a destination VLAN number of the packet data, or output to the other packet transfer unit 1330 -i via the communication data internal input/output unit 1331 -i (i=1 to n) and a switching unit 1310 . The packet transfer unit 1330 -i transmits the received packet data to the communication data internal input/output unit 1321 -i−k set according to the destination IP address, the destination MAC address, the destination MPLS label number, or the destination VLAN number of the packet data received from the switching unit 1310 . The illegal communication defense unit 1320 -i outputs the packet data received via the communication data internal input/output unit 1321 -i−k to the communication data input/output unit 1332 -i−k.
While the present invention has been described in detail and pictorially in the accompanying drawings, the present invention is not limited to such detail but covers various obvious modifications and equivalent arrangements, which fall within the purview of the appended claims.
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A reconfigurable processor equipped with reconfigurable circuits (RCs) comprises unit A for dividing data input to the processor, and outputting a part of pieces of divided data to a RC, unit B for selecting or binding at least one piece of divided data among divided data which is not outputted from the input data dividing unit and output data of the RC to output processed data to other RCs, at least one RS buffer for temporarily storing data input to unit B to match timings of output from the RC and output from the RS buffer, unit C for binding the output data of the RC, unit A, and unit B to output data from the processor, and at least one RO buffer for temporarily storing data input to unit C to match the timings of output from the RC, output from unit A, and output from unit B.
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FIELD OF THE INVENTION
[0001] The present invention relates to cured composites built from layers of unidirectional fibers. In particular, the invention utilizes highly porous lightweight materials in conjunction with multilayer preforms to obtain cured articles with improved toughness.
BACKGROUND OF THE INVENTION
[0002] High-preformance composite materials built of alternating layers of unidirectional reinforcing fibers have an advantageous combination of high strength and light weight. As such they find use in aerospace and other industries where such properties are critical. Generally, the composite materials are prepared by laying up a number of alternating layers wherein adjacent layers have unidirectional fibers running at different angles. The net effect of buildup of several layers of such unidirectional fabrics is to provide a composite material having exceptional strength, either quasi-isotropically, or in one or more particular directions.
[0003] Such composite materials may be produced as prepregs or as preforms. In prepregs, layers of unidirectional fabrics immersed or impregnated with a resin are laid-up into the shape of the part to be produced from the composite material. Thereafter, the laid-up part is heated to cure the resin and provide the finished composite part. In the preform approach, layers of unidirectional reinforcing fibers or woven, braided, or warp-knit fabric are laid up similarly to the way they are laid-up in prepregs. However, in the preform method, the layers are laid-up dry. Thereafter, the laid-up material is infused with resin in a liquid-molding process, and the molded part is heated to cure the resin as in the prepregs.
[0004] The alternating layers, or lamina, of reinforcing fibers provide the composite articles made from the prepreg or preform process with a great deal of strength, especially in directions that align with specific fiber directions. Accordingly, very strong lightweight parts may be produced, for example, as wings and fuselages of aircraft. Although the alternating lamina of reinforcing fibers provide strength, toughness or impact resistance is determined mainly by the properties of the cured resin. Impact-resistant or toughened resins are preferred because they are resistant to damage from impact. This is important, for example, in the case of airplane wings made from such composite materials. Any failure from foreign-object impact during flight would be catastrophic for the airplane to which the wing is attached. Also, any damage resulting from ground-maintenance impact (e.g. from tool drop, forklifts or other vehicles) would require replacement of the entire piece, because such composite materials are built up as a single piece. Furthermore, because impact damage in composite materials is generally not visible to the naked eye, it is important for such primary load-bearing structures to be able to carry their full design load after impact and prior to detection using non-destructive techniques.
[0005] In prepregs, the resin, typically an epoxy-based formulation, may be toughened by adding particles of a thermoplastic material to the conventional resin. These thermoplastic particles may either be soluble in the matrix resin and dissolve in the epoxy resin or may be insoluble and placed, during the prepregging operation (see, for example, U.S. Pat. No. 5,028,478) on the surface of each layer. Upon cure, the thermoplastic resin in the cured epoxy matrix serves to limit crack propagation through the part. Preform materials may be stitched before resin infusion and cure to provide toughness and crack resistance. One drawback to stitching is the reduction of in-plane mechanical properties, particularly as the stitch density increases. The prepreg approach of applying particles of thermoplastic material to the resin before cure is not directly transferable to the liquid molding processes used to prepare preform articles. In the resin infusion of the liquid molding process, soluble thermoplastics tend to increase the melt-flow viscosity of the matrix resin unacceptably, while insoluble thermoplastic toughening particles tend to be filtered by the preform and thus will not be located uniformly between the plies in the preform.
[0006] In the European Patent EP 1 175 998 to Mitsubishi, laminated products formed of reinforcing fibers are provided in which thermoplastic resin layers are provided between layers of the reinforcement fiber. The thermoplastic resin layer is described in the form of a porous film, fiber, network structure, knitted loop, and the like. The laminated product uses a thermoplastic layer of sufficient permeability between the layers of reinforcing fibers so as not to inhibit liquid resin flow during a liquid molding process. One drawback inherent in processes such as those described in EP 1 175 998 is that the preforms made of alternating layers of reinforcing fibers and thermoplastic resin layers are less than perfectly stable during resin infusion. As a result, the reinforcing fibers and the thermoplastic resin layer tend to move or shift during the liquid molding process. Such moving or shifting can be mitigated by stitching together the layers before infusion with the resin. Another drawback to the processes described in EP 1 175 998 is that they are primarily effective for hand lay-up operations and not for automated lay-up operations that would be more relevant in the fabrication of large aircraft parts or in the continuous production of broad goods.
[0007] It would be desirable to provide a molded article made by a preform process in which the reinforcing fibers are held tightly in relative orientation to one another. It would further be desirable to provide a process for making such a preform article in widths and lengths feasible for producing large-scale parts, such as airplane wings, from them.
SUMMARY OF THE INVENTION
[0008] In one embodiment, the invention provides a multiaxial preform made up of reinforcing layers of unidirectional fibers. Non-woven interlayers made of spunbonded, spunlaced, or mesh fabric of thermoplastic fibers are disposed between and melt-bonded or stitched to the reinforcing layers. The multiaxial preform is used in a liquid-molding process by which resin is infused into the preform, followed by heating to gel and set the resin. The interlayers are permeable to permit the flow of resin during the liquid-molding operation. In a preferred embodiment, the interlayer material is melt-bonded to at least one of the unidirectional layers, preferably on both sides. The layers are further held together with knit threads. The melt-bonded interlayers hold the unidirectional fibers in place during the resin infusion and subsequent curing of the resin to produce a fiber reinforced composite material. In a preferred embodiment, the unidirectional fibers are made of carbon fibers. The material making up the interlayers is chosen for compatibility with the resin upon curing. In one embodiment, the resin is an epoxy resin and the interlayer fibers are made of a polyamide.
[0009] In another embodiment, the invention provides a method for manufacturing a multiaxial fabric made of reinforcing layers of unidirectional fiber, with non-woven interlayers disposed between the reinforcing layers. The method includes the step of melt-bonding an interlayer material made of thermoplastic fibers to one or both sides of a unidirectional dry fabric to produce a dry unidirectional tape. Thereafter, a preform may be built up from the unidirectional tape by laying down the tape with at least one other layer or lamina of unidirectional fibers at angles between −90 and +90° from the warp direction of the multiaxial fabric.
[0010] In a preferred embodiment, alternating unidirectional fibers is accomplished by building up the preform from a plurality of dry unidirectional tapes. The layers of the preform are preferably stitched together. Fabric-reinforced composite materials may be prepared by molding such a preform and infusing the preform in the mold with a thermosetting resin in a liquid-molding process.
[0011] The lamina of unidirectional fibers in the multiaxial fabric may be laid-down in quasi-isotropic or orthotropic patterns. The pattern may be repeated as needed to achieve a desired thickness of the finished part. The repeated pattern may be constant, or may be varied across the preform. Where the repeated pattern is varied across the preform, the locally different thicknesses may be mechanically held in place, such as by stitching, tufting, or heating to melt-bond the multilayers together. Alternatively, a localized “tackifier”, such as are known in the trade, may be used for holding preform pieces in place mechanically.
[0012] Conventional methods for manufacturing large-scale preform materials may be modified to produce multiaxial fabrics containing reinforcing layers of unidirectional fibers with non-woven interlayers disposed between the reinforcing layers and melt-bonded to at least one of them. In one method, a plurality of tows is first pulled across a set of pins to create reinforcing layers of unidirectional fibers. An interlayer material is introduced to reside between the reinforcing layers, and the layers of unidirectional fibers are knitted together to form a multilayer stack. The interlayer material may be attached to individual reinforcing layers via heating without causing all layers to be melt-bonded to each other.
[0013] Fiber-reinforced composite materials may be made by molding a preform and infusing the preform with a thermosetting resin in a number of liquid-molding processes. Liquid-molding processes that may be used in the invention include, without limitation, vacuum-assisted resin transfer molding (VARTM), in which resin is infused into the preform using a vacuum-generated pressure differential. Another method is resin transfer molding (RTM), wherein resin is infused under pressure into the preform in a closed mold. A third method is resin film infusion (RFI), wherein a semi-solid resin is placed underneath or on top of the preform, appropriate tooling is located on the part, the part is bagged and then placed in an autoclave to melt and infuse the resin into the preform. The RFI method is described in U.S. Pat. No. 4,311,661, the disclosure of which is incorporated by reference.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
[0015] [0015]FIG. 1 is a schematic side view of the preferred thermoplastic fibers;
[0016] [0016]FIG. 2 illustrates a stitched preform;
[0017] [0017]FIG. 3 illustrates a process for preparing a unidirectional dry tape; and
[0018] [0018]FIG. 4 illustrates a process for producing a preform.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
[0020] In a first aspect of the invention, a multiaxial fabric is prepared that is made of alternating layers of reinforcing unidirectional fibers and non-woven interlayers. The non-woven interlayers comprise a spunbonded, spunlaced, or mesh fabric of thermoplastic fibers. The interlayers are disposed between and knit-stitched to the reinforcing layers. In a preferred embodiment, the thermoplastic interlayers are melt-bonded to at least one of reinforcing unidirectional fabric layers. Such multiaxial fabrics may be manufactured by a number of processes to produce preforms that are 12-300′ wide.
[0021] In another aspect, fiber reinforced composite materials are made by molding a multiaxial preform such as described above, and infusing the preform with a thermosetting resin in a liquid-molding process. After infusion of the preform, the component is heated in the mold to gel and set the resin.
[0022] Layers of unidirectional fibers for use in the multiaxial preforms and fiber reinforced composite materials of the invention are well known in the art. In a preferred embodiment, the unidirectional fibers are made of carbon fibers. Other examples of unidirectional fibers include, without limitation, glass fibers and mineral fibers. Such layers of unidirectional fibers are usually prepared by a laminating process in which unidirectional carbon fibers are taken from a creel containing multiple spools of fiber that are spread to the desired width and then melt-bonded to a thermoplastic interlayer, as described above, under heat and pressure.
[0023] The interlayer is made of a spunbonded, spunlaced, or mesh fabric of thermoplastic fibers. The thermoplastic fibers may be selected from among any type of fiber that is compatible with the thermosetting resin used to form the fiber reinforced composite material. For example, the thermoplastic fibers of the interlayer may be selected from the group consisting of polyamide, polyimide, polyamideimide, polyester, polybutadiene, polyurethane, polypropylene, polyetherimide, polysulfone, polyethersulfone, polyphenylsulfone, polyphenylene sulfide, polyetherketone, polyethertherketone, polyarylamide, polyketone, polyphthalamide, polyphenylenether, polybutylene terephthalate and polyethylene terephthalate.
[0024] In a preferred embodiment, the thermoplastic fibers are made from two or more materials. For example, the two or more materials may be prepared by mechanically mixing different fibers, which are used to create the spunbonded, spunlaced, or mesh fabric. In a preferred embodiment, the two or more materials may be used to form a bi-component fiber, tri-component fiber or higher component fiber to create the interlayer fabric. Non-limiting examples of bi-component fibers are illustrated schematically in FIG. 1. FIG. 1( a ) shows in cross-section a fiber made for example by coextrusion of a fiber material A and a fiber material B. Such a fiber may be produced by a spinneret with two outlets. FIG. 1( b ) shows a bi-component fiber made from materials A and B such as would be produced by extrusion through four spinnerets. Similarly, FIG. 1( c ) shows a bi-component fiber spun from eight spinnerets. In a preferred embodiment, the bi-component fiber is used in the form of a core sheath fiber such as illustrated in FIG. 1( d ). In a core sheath fiber, a fiber material of one type, illustrated as B in FIG. 1( d ) is extruded as the core, while a fiber material of another type, illustrated as A in FIG. 1( d ) is extruded as the sheath.
[0025] Bi-component fibers such as illustrated in FIG. 1, and other fibers containing more than two components are well known in the art and can be made by a number of conventional procedures. Additionally, although the fibers in FIG. 1 are illustrated schematically with circular cross-sections, it is to be appreciated that other cross-sections may be used.
[0026] In a preferred embodiment, the interlayer material is made of bi-component fibers containing a sheath of one material and a core of another. In a particularly preferred embodiment, the sheath is made of a polyurethane and the core is made of a polyamide.
[0027] In a preferred embodiment, the fibers making up the interlayer have diameters from 1 to 100 microns, preferably from 10 to 75 microns and more preferably from 10 to 30 microns. In another embodiment, the thermoplastic fibers have diameters from 1 to 15 microns.
[0028] The interlayer material may have a wide range of areal densities. The areal density may be chosen according to the amount required to impart the desired impact resistance, as verified for example by compression-after-impact testing according to Boeing test method BSS 7260. The desired impact-resistance level is determined on a part-by-part basis assuming specific impact-energy levels. In one embodiment, the interlayer material has a areal density of 1-50 grams/square meter. In another embodiment, the areal density of the interlayer is about 2-15 grams/square meter.
[0029] The interlayer material may be a spunbonded fabric. Spunbonded fabrics are produced from continuous fibers that are continuously spun and bonded thermally. These fabrics are commercially available from a wide variety of sources, primarily for the clothing industry. Preferred fabrics have areal weights that are generally lower than those of fabrics used in clothing.
[0030] In another embodiment, the interlayer is a spunlaced fabric. Spunlaced fabrics are prepared from continuous fibers that are continuously spun and bonded mechanically. These fabrics are commercially available from a wide variety of sources, primarily for the clothing industry. As for the spunbonded fabrics, preferred spunlaced fabrics have areal weights that are generally lower than those commonly used in the clothing industry.
[0031] In another embodiment, the interlayer comprises a mesh fabric. In a preferred embodiment, the mesh construction contains between 0.5 and 15 threads per inch in the warp and weft directions.
[0032] The multiaxial preform comprises a plurality of reinforcing layers with interlayers disposed between the reinforcing layers and melt-bonded to at least one of the reinforcing layers. It is preferred to use multiaxial preforms having 4 or more reinforcing layers of unidirectional fabrics. In another embodiment, the preform has from 2-16 layers of unidirectional fabrics.
[0033] The lamina may be laid-down in a quasi-isotropic pattern. A quasi-isotropic pattern is one that approximates an isotropic material in the plane of the fibers. This is also known as transverse isotropy. For example it is possible to lay-down lamina in a quasi-isotropic 0/+45/90/−45 pattern. To illustrate, other quasi-isotropic patterns include +45/0/−45/−90 and −45/0/+45/90. Another quasi-isotropic pattern is 0/+60/−60.
[0034] In another embodiment, the lamina may be laid-down in an orthotropic pattern. Orthotropic means having fibers or units such that the net result is not quasi-isotropic in plane like the quasi-isotropic patterns just described. An example of an orthotropic pattern is one with 44% 0°, 22% +45°, 22% −45° and 12% 90° fibers. In this example, greater longitudinal strength (along the 0°-direction) and lower shear strength (±45°-direction) and transverse strength (90°-direction) than a quasi-isotropic (25/50/25) lay-up are achieved. The resulting built-up lamina provide higher strength and thickness in the 0° direction as compared to a quasi-isotropic laminate, but provide lower shear strength and thickness (provided by the ±45°layers). Correspondingly, in the example, the 90° strength is lower than a quasi-tropic laminate. The term orthotropic is well understood in the field. For example a 0° fabric is orthotropic, as well as any other pattern that does not result in balanced average in plane (i.e. quasi-isotropic) properties.
[0035] As noted above, it is common to prepare the laminae in sets of four. Where desired, the pattern of four laminae may be repeated to achieve a desired thickness. In a preferred embodiment, when it is desired to build-up a desired thickness, mirror-image lamina stacks are used to prevent post-cure bending and twisting due to thermal stresses created after curing the resin at elevated temperature. In such a case, the total lay-up would be made up of groups of balanced laminae, or laid-up alternately to balance the laminate. This practice is common in the field and is done to ensure the fabrication of flat parts and to avoid the problem of parts with unknown and/or temperature-sensitive configurations.
[0036] In one embodiment, the interlayers made of thermoplastic fibers are melt-bonded to the unidirectional fiber layers between which they are disposed. Such melt-bonding acts to maintain the orientation of the unidirectional fibers in place during resin infusion into the mold during a (subsequent) liquid-molding process. In addition, the multiaxial preform may be knitted or sewed together with thread to hold the fabric layers together during resin infusion and cure. In an alternative embodiment, a warp-knit, multiaxial fabric may be assembled by knit-stitching the reinforcing layers together with thermoplastic interlayers between the reinforcing layers. The knit thread or sewing thread may be selected from a variety of materials, including without limitation, polyester-polyarylate (e.g. Vectran®), polyaramid (e.g. Kevlar®)), polybenzoxazole (e.g. Zylon®)), viscose (e.g. Rayon®)), acrylic, polyamide, carbon, and fiberglass). Where desired, the knitting or sewing step is carried out after the initial lay-up of the multiaxial preform. The same kinds of threads may be used to hold locally different thicknesses mechanically in place by stitching and by tufting, as discussed above.
[0037] [0037]FIG. 2 shows a multiaxial preform for a composite material for use in a liquid-molding process of the invention. In FIG. 2, interlayers 6 made of thermoplastic fibers are disposed between reinforcing fabric layers 2 of unidirectional fabrics. In a preferred embodiment, at least some of the interlayers are melt-bonded to an adjacent reinforcing fabric layer. A sewing thread 8 may be used to hold the preform layers together.
[0038] In another embodiment, the invention provides a multiaxial warp knit fabric where the thermoplastic interlayer is melt-bonded only to the 0-degree layers with the non-0-degree layers and other interlayers attached to the 0-degree layer using a knit thread. In a preferred embodiment, only the 0-degree layer is melt-bonded. To illustrate, an example lay-up is thermoplastic (TP) interlayer not melt-bonded/±45° fibers/TP interlayer melt-bonded to top of 0° layer/0° fibers/TP interlayer melt-bonded to bottom of 0° layer/−45° fibers/TP interlayer not melt-bonded/90° fibers with the whole assembly knitted together.
[0039] The 0-degree layer is generally used as the primary load carrying direction. By stabilizing the 0-degree layer in the preferred embodiment by melt-bonding a thermoplastic interlayer, the strength of the resulting molded part is increased without having to melt-bond the other directions. Although in this embodiment the other directions are not necessarily strengthened as much as the 0-degree layer, the other layers will generally contribute to greater impact resistance of the molded part due to the presence of non-bonded interlayer material.
[0040] In one embodiment, an interlayer material may be melt-bonded to one or both sides of a unidirectional dry fabric to produce a dry unidirectional tape. FIG. 3 illustrates such a process. A veil 12 made of the interlayer material is fed from rollers 13 and laminated to a unidirectional dry fabric 14 . The veil 12 is melt bonded to the fabric 14 , for example by passing between heated rollers 16 , to produce a fabric 18 having a veil material melt bonded to the unidirectional fibers. The fabric 18 may be provided in the form of a dry unidirectional tape. FIG. 3 a shows a detail of the construction of a fabric 18 with interlayer material 12 melt bonded to both sides of the unidirectional dry fabric 14 . In an alternative embodiment, the veil material 12 may be melt-bonded to only one side of the unidirectional fibers 14 . However, it is preferred to melt-bond the interlayer material on both sides of the unidirectional dry fabric to produce a tape with easier handleability.
[0041] The dry unidirectional tape 18 may be used to assemble a multiaxial preform in a continuous process, such as disclosed in EP0972102/WO9844183 by Hexcel, the disclosure of which is hereby incorporated by reference. In a process described in the Hexcel patent, unidirectional dry tapes are introduced along a moving bed to produce a multiaxial lay-up. The Hexcel patent describes a method wherein several unidirectional webs are stacked in different directions and mutually linked. At least one of the unidirectional webs is provided with cohesion for manipulation before being stacked with the other web. In the Hexcel patent, cohesion is provided for example by physical entanglement, chemical adhesives, or by providing the web with stitch filaments that may be melted with heat to provide cohesion between the fibers of the unidirectional webs.
[0042] In one aspect, the present invention provides unidirectional webs with good cohesion for manipulation before being stacked. The cohesion is provided by a spunlaced, spunbonded or mesh fabric melt-bonded to a layer of unidirectional fibers. Dry unidirectional tapes may be prepared by the process illustrated in FIG. 3.
[0043] A process for making the preform of the invention is schematically illustrated in FIG. 4. In the method of FIG. 4, unidirectional tapes are provided on unidirectional tape rolls 51 and on longitudinal roll 53 . Longitudinal roll 53 may hold a plurality of rolls of unidirectional fabric to achieve a desired width. Tape rolls 51 are associated with lay-up devices 52 and tape delivery heads 55 that lay down four plies of fabric on a moving conveyor 54 . The lay-up devices are disposed at a plurality of angles relative to the warp direction, corresponding to the desired pattern of buildup of the four-layer preform material. After all four layers are laid down, the fabric passes through a knitting unit 56 and is taken up on take-up spool 57 .
[0044] Alternatively, a device such as described in Hagel, U.S. Pat. No. 5,241,842 or Wunner, et al., U.S. Pat. No. 6,276,174 (the disclosures of which are incorporated by reference; see also pictures and video at http://www.liba.de/tricot/cop_max_layer.htm) may be used to prepare multiaxial preforms by providing tows of unidirectional carbon fibers. One or a plurality of tows is pulled across pins to create reinforcing layers of unidirectional fibers. In this embodiment, a means is provided for introducing the interlayer material between the layers of unidirectional carbon fibers. Because the interlayer material is non-directional, it need not be introduced at an angle in the way that the unidirectional carbon fibers are.
[0045] The multiaxial preforms of the invention may be made into cured fiber-reinforced composite materials by a variety of liquid-molding processes. In one, vacuum-assisted resin transfer molding, a resin is introduced to a mold containing the multiaxial preform under vacuum. The resin infuses the preform and saturates the interlayers between the layers of unidirectional fibers. The interlayers are made of a material that is permeable to permit the flow of resin during the liquid-molding operation. Furthermore, the melt-bonded interlayers hold the unidirectional fibers in place during the resin infusion.
[0046] In another method, resin transfer molding, resin is infused under pressure into a closed mold. These and other liquid-molding processes may be used to prepare the cured fiber-reinforced composite material of the invention.
[0047] Following infusion of the resin in the mold in a process such as those described above, the mold is heated to cure the resin to produce the finished part. During heating, the resin reacts with itself to form crosslinks in the matrix of the composite material. After an initial period of heating, the resin gels. At gel, the resin no longer flows, but rather behaves as a solid. In a preferred embodiment, it is important to gel the resin at a temperature below the melting point of the thermoplastic fibers of the interlayer in order to prevent their melting and flowing into the reinforcement fiber bundles. After gel, the temperature or cure may be ramped up to a final temperature to complete the cure. The final cure temperature depends on the nature and properties of the thermosetting resin chosen. For the case of aerospace-grade epoxy resins, it is conventional to ramp the temperature after gel up to a temperature range of 325 to 375° F. and hold at this temperature for 1 to 6 hours to complete the cure.
EXAMPLES
[0048] The results shown below are for compression-after-impact (CAI) panels made and tested according to BMS 8-276 (a Boeing material specification for a toughened prepreg system used for commercial aircraft) using BSS 7260 Type II, Class 1 impact with an impact energy of 270 in-lb.
[0049] Test panels were prepared as follows. The panel lay-up was (+45/0/−45/90) 3S using unidirectional fabric from Anchor Reinforcements (Huntington Beach, Calif.) to which spunbonded fabric had been melt-bonded. A control used only a thermoplastic weft fiber to hold the fabric together. The three spunbonded fabrics were supplied by Spunfab (Cuyahoga Falls, Ohio) in areal weights of 0.125, 0.250, and 0.375 oz/yd 2 . The three materials used were PE2900, a polyester; V16010, a ternary polymer blend; and PA1008, a polyamide.
[0050] A dry, uni-directional tape 13-inches in width was prepared by melt-bonding the respective spunbonded fabrics onto a tape containing 190 g/m 2 of T700 carbon fibers (Toray, Tokyo, Japan). The uni-directional tape was cut in the same manner as prepreg and laid-up according to BMS 8-276 as described above. The laid-up fabric was VARTM processed using an epoxy resin, TV-15, from Applied Poleramic, Inc. (Benicia, Calif.). After infusion and cure, the resulting panels were machined into 4″×6″ impact test specimens according to BSS7260. Impact was preformed using a 0.3125″ spherical steel tup. Four panels for each construction were tested.
[0051] After impact, all specimens were ultrasonically C-scanned. In these figures, a through-transmission amplitude plot and the bottom row shows a time-of-flight response was prepared. Impact damage areas were calculated directly from the center “hole” shown in the amplitude plots using the built-in software tool on the C-scan apparatus. These results are shown in Table 1.
[0052] Compression-after-impact strength results are shown in Table 2 and panel thicknesses and per-ply thicknesses are shown in Table 3. Tables 1 and 2 show significant decreases in impact damage area for the PA1008 and V16010 interlayer materials as well as significant increases in compression-after-impact strength for these same materials, respectively. Table 3 shows that the interlayer-toughening concept meets the current commercial Boeing specification (BMS 8-276) for per-ply thickness.
TABLE 1 Average Impact Damage Area for Three Panels vs. Control. Percent Change in Impact Impact Damage Area (in 2 ) Area Interlayer Areal Weight Interlayer Areal Weight Spunbonded 0.125 0.250 0.375 0.125 0.250 0.375 Examples Fabric none oz/yd 2 oz/yd 2 oz/yd 2 oz/yd 2 oz/yd 2 oz/yd 2 Comparative Control 7.134 N/A N/A N/A 1 PE2900 8.258 8.632 10.037 15.8 21.0 40.7 2 V16010 4.529 3.936 2.093 −36.5 −44.8 −70.7 3 PA1008 1.489 1.160 0.619 −79.1 −83.7 −91.3
[0053] [0053] TABLE 2 Average Compression-After-Impact Strength for Three Panels vs. Control. Percent Change CAI CAI Strength (ksi) Strength Interlayer Areal Weight Interlayer Areal Weight Exam- 0.125 0.250 0.375 0.125 0.250 0.375 ples none oz/yd 2 oz/yd 2 oz/yd 2 oz/yd 2 oz/yd 2 oz/yd 2 Com- 19.3 para- tive 1 17.2 15.6 13.8 −10.9 −19.2 −28.6 2 20.5 24.3 29.4 6.1 26.2 52.6 3 30.6 27.8 39.6 58.6 44.4 105.3
[0054] [0054] TABLE 3 Average Cured-Panel Thicknesses. Average Per-Ply Thickness (mil)* Average Panel Thickness (in) Interlayer Areal Weight 0.250 0.375 0.125 0.250 0.375 Examples none 0.125 oz/yd 2 oz/yd 2 oz/yd 2 none oz/yd 2 oz/yd 2 oz/yd 2 Comparative 0.170 7.08 1 0.175 0.185 0.186 7.29 7.71 7.75 2 0.173 0.182 0.180 7.21 7.58 7.50 3 0.177 0.189 0.187 7.38 7.88 7.79
[0055] 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, which is defined in the appended claims.
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Materials and methods are provided for producing preform materials for impact-resistant composite materials suitable for liquid molding. An interlayer comprising a spunbonded, spunlaced, or mesh fabric is introduced between non-crimped layers of unidirectional reinforcing fibers to produce a preform for use in liquid-molding processes to produce composite materials. Interlayer material remains as a separate phase from matrix resin after infusion, and curing of the preform provides increased impact resistance by increasing the amount of energy required to propagate localized fractures due to impact. Constructions having the interlayer materials melt-bonded to the reinforcing fibers demonstrate improved mechanical preformance through improved fiber alignment compared to other fabrication and preforming methods.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention is related to the structure of a container, and in particular to one for carrying round, cylindrical, or odd shaped objects such as propane tanks securely.
[0003] 2. Description of the Prior Art
[0004] Due to the busy work schedule, the modern man places special importance on convenience and comfort in everyday home living. During picnic outings, the transportation of cooking essentials such as propane tanks, pots, and pans has regularly caused problems. The main reason is that these objects are either too heavy or too bulky to transport. The round or cylindrical shapes of the objects make it difficult to remain stationary in a vehicle during transportation, thus creating problems while traveling. In particular, when used for picnics, or when refilling, the size, weight, and non-angular shape of these objects, while placed in vehicles, often cause them to roll around and crash, creating unsafe incidents and damage to the transport vehicle. As a result, these objects are usually placed in extra-large bag-like containers, tightly packed, in an attempt to preserve and transport. However, it is not possible to properly pin-down the objects during the actual transport. They inevitably roll in the trunk, the seat of a vehicle, or the bed in the back of a pickup truck, which is the dilemma, encountered by most people.
[0005] Also, because of difficulty in securing objects of round, cylindrical and irregular shapes, such as vases, can-shaped objects, and especially easily breakables made of glass such as porcelain, etc.; professional packers are usually required for safe transport. However, it is not possible for unprofessional people to perform a packaging service of professional standard. This not only requires specialized skills, but often very large space.
[0006] In the case of self-transported small- and medium-sized objects, how can one satisfactorily manage the packaging and how can one safely place the simple-packed objects inside a vehicle.
[0007] Based on the special need for efficient packaging of valuable, heavy objects during transportation, the development of an assisting tool capable of safely packing the objects and ensuring they remain stationery in a vehicle during transportation, should be aggressively looked into by industry.
[0008] Therefore, it is an objective of the present invention to provide a safety container for carrying a propane tank or the like which can obviate and mitigate the above-mentioned drawbacks.
SUMMARY OF THE INVENTION
[0009] This invention is related to a safety container for carrying round, cylindrical, or odd shaped objects such as propane tanks.
[0010] It is the primary object of the present invention to provide a safe, convenient and clean way to transport a propane tank via vehicles such as trucks, sport utility vehicles or cars to and from refill locations.
[0011] It is another object of the present invention to provide a safety container, which can restrict and stabilize an object during transportation.
[0012] It is still another object of the present invention to provide a safety container, which can prevent an object from rolling over.
[0013] It is still another object of the present invention to provide a safety container, which can prevent an object from tipping.
[0014] It is still another object of the present invention to provide a safety container, which can prevent the surface of an object from coming into contact with either the person or the interior of the transport vehicle.
[0015] The foregoing objects and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts.
[0016] Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is an exploded view of a safety container according to the present invention;
[0018] FIG. 2 is a perspective view illustrating a propane tank, which is kept within the safety container according to the present invention;
[0019] FIG. 3 is a perspective view illustrating a propane tank, which is completely wrapped inside the safety container according to the present invention;
[0020] FIG. 4 is a sectional view of FIG. 2 ;
[0021] FIG. 5 is an exploded view of a safety container in the shape of a dog bone according to the present invention;
[0022] FIG. 6 illustrates the collapsed condition of the safety container according to the present invention; and
[0023] FIG. 7 is an exploded view of a safety container according to another preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0024] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings. Specific language will be used to describe the same. It will, nevertheless, be understood that no limitation of the scope of the invention is thereby intended, alterations and further modifications in the illustrated device, and further applications of the principles of the invention as illustrated herein being contemplated as would normally occur to one skilled in the art to which the invention relates.
[0025] With reference to the drawings and in particular to FIGS. 1, 2 , 3 and 4 thereof, the safety container according to the present invention comprises a rectangular body 10 which is made of soft material such as cloth. The body 10 can be circular in shape, or shaped as required. The body 10 is formed with an opening 11 through which an inflatable cushion 12 can be inserted into the body 10 . The inflatable cushion 12 may be filled with fluid as required. The opening 11 is provided with enclosure means such as male and female fasteners, zippers, or the like so that the opening 11 can be closed to prevent the cushion 12 from getting out of the body 10 . Two long sides of the body 10 are each provided with an inverted U-shaped handle 13 for holding the safety container. On the upper edge of the two long sides of the body, 10 is fixedly or removably connected with a flap 14 for keeping an article in place. Two short sides of the body 10 are each provided with a fastening strip 15 for engaging with a removable flap 14 for further keeping the article in place. The cushion 12 has a nozzle 16 , which extends out of an opening of the body 10 for filling air or fluid therein. The cushion 12 has a cavity at the central portion surrounded by raised edges so that an article can be firmly kept in the cavity.
[0026] The present invention utilizes the inflatable cushion 12 to keep an article to be resiliently mounted within the body 10 and flaps 14 to secure the article in place thereby safely keeping the article in the body 10 . As shown in FIGS. 2, 3 and 4 , when a propane tank 20 is placed in the cushion 12 , the propane tank 20 will automatically slip into the cavity at the central portion of the cushion 12 due to the gravity. Then, the upper portion of the propane tank 20 is wrapped with the flaps 14 thereby firmly keeping the propane tank 20 in the cushion 12 and therefore enabling the propane tank 20 to be carried safely.
[0027] Since the cushion 12 is filled with air or fluid, the air or fluid may be released from the nozzle 16 of the cushion 12 when the safety container is not in use. Hence, the safety container can be folded as shown in FIG. 6 thus making it easy to stow or transport. Furthermore, the cushion 12 can be used as a pillow in camping. Moreover, the expansion degree of the cushion 12 can be adjusted by controlling the air or fluid in the cushion 12 so as to adapt to different kinds of articles.
[0028] FIG. 5 illustrates a second preferred embodiment of the present invention. As shown, the cushion 12 has a dog bone profile which is sized to partially wrap the side of the propane tank. The ends of the bone profile grip the tank side when the propane tank in placed on the cushion and the weight of the tank forces the center of the dog bone down until it makes contact with the supporting surface.
[0029] FIG. 7 is an exploded view of a safety container according to another preferred embodiment of the present invention. As shown, all flaps 14 are detachably engaged with the body 10 .
[0030] 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 methods differing from the type described above.
[0031] While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.
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A safety container, which includes a body, provided with a plurality of flaps and two or more handles, and a cushion removably fitted in the body, whereby an object is first placed in the cushion and the flaps are then wrapped on the object to keep the object in place thereby securing the object in the body.
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BACKGROUND
(1) Field of the Invention
[0001] The invention relates to a refrigeration installation having at least one refrigeration consumer, which includes at least one evaporator, having at least one feed line and at least one discharge line, via which the refrigerant or refrigerant mixture is fed to the refrigeration consumer(s) and discharged from the refrigeration consumer(s), respectively, the evaporator(s) being assigned expansion members.
[0002] Furthermore, according to a first alternative, the invention relates to a method for operating a refrigeration installation in which the refrigeration compressor(s) is/are assigned modified expansion valves and modified linear compressors.
[0003] According to a second alternative, the invention relates to a method for operating a refrigeration installation, in which the conventional expansion valve(s) and the conventional compressor(s) of the refrigeration consumer(s) is/are assigned bypass lines.
[0004] In the text which follows, the term “modified expansion valves” is to be understood as meaning all expansion valves which, in addition to the primary function of “expansion of a liquid”, have the secondary function of “realization of a fluid connection”. The term “modified compressor” in the text which follows encompasses all compressors which, in addition to the primary function of “compression of a gas”, also allow the secondary function of “realization of a fluid connection”.
[0005] The terms “conventional expansion valves” and “conventional compressors” in the text which follows are to be understood as meaning all known designs of expansion valves and compressors which do not have the above-mentioned secondary function.
[0006] Refrigeration installations of the generic type are used for example in supermarkets or hypermarkets, where they generally supply a multiplicity of refrigeration consumers, such as cold stores, refrigerator cabinets and/or freezer cabinets. For this purpose, a one-component or multicomponent refrigerant or refrigerant mixture circulates inside them. A refrigeration installation of this type—as is known from DE-C 39 28 430—has a liquefier, in which the pressurized refrigerant (mixture) is condensed by indirect heat exchange, preferably against outside air.
[0007] The liquid refrigerant (mixture) from the liquefier is fed to a collection vessel that is optionally to be provided. Within a refrigeration installation, there must always be enough refrigerant to ensure that the evaporators of all the refrigeration consumers can be filled even during the maximum demand for refrigeration. However, since when the demand for refrigeration is lower some evaporators are only partially filled or are even completely empty, the excess refrigerant (mixture), during these times, has to be collected in the collection vessel provided for this purpose.
[0008] The refrigerant (mixture) is fed from the collection vessel to the refrigeration consumers via at least one liquid line. An expansion device, preferably an expansion valve, in which the refrigerant (mixture) flowing into the refrigeration consumer or the evaporator(s) of the refrigeration consumer is expanded, is connected upstream of each refrigeration consumer. The refrigerant (mixture) which has been expanded in this way is evaporated in the evaporators of the refrigerant consumers and thereby cools the corresponding refrigeration cabinets or cold stores.
[0009] The evaporated refrigerant (mixture) is then fed via a suction line to a compressor unit. These compressor units may be of single-stage or multistage design. The individual compressor stages generally have a plurality of compressors connected in parallel, which compress the refrigerant (mixture) and pass it back, via a riser, to the liquefier which has already been mentioned. Whereas the compressor unit is normally positioned, for example, in a machine room arranged in the basement of a supermarket, the liquefier is located on the roof of the supermarket.
[0010] The compressors used are generally oil-lubricated reciprocating piston compressors which are driven in rotation. One drawback in this case is that corresponding measures have to be taken to allow the oil released from the reciprocating piston compressor to be separated from the refrigerant (mixture). Furthermore, it is generally necessary to ensure that the oil which has been separated off is fed back to the reciprocating piston compressor(s). To enable the oil to be separated off, the mixture of refrigerant and oil first of all has to be passed to specific points within the cycle, and consequently minimum velocities have to be reached in rising suction and pressure lines, since the oil would not otherwise be entrained. These minimum velocities mean small pipe diameters, resulting in additional, undesired pressure losses and therefore energy losses. To avoid these pressure and energy losses in risers, it is necessary to split lines, but this in turn results in increased installation outlay. Therefore, process aspects are undesirably closely linked to economic aspects.
[0011] As an alternative to the procedure described above, the system of a cold vapor refrigeration installation, in which a distinction is drawn between subcritical (with reliquefaction) and supercritical (with gas recooling) operation, so that a “gas cooler” is used instead of the “liquefier” component, it is also possible for a gaseous refrigerant (mixture) to circulate in a refrigeration installation, which under the given boundary conditions (pressure, temperature, etc.) is not in liquid form at any time. This is then what is known as cold gas refrigeration installation, also referred to as a Joule, Stirling or Gifford-McMahon installation.
[0012] The text which follows will simply use the term “liquefier”. If the process in question is a cold vapor compression process in the two-phase range, it is actually a liquefier that is used. In the case of a supercritical procedure or gas processes, the term “liquefier” in turn stands for a gas cooler. It is essential for heat to be dissipated from the cycle process. The liquefaction can take place in an air-cooled apparatus, in an intermediate-pressure separator or alternatively by means of a further assembly connected in a cascade. A cascade connection is present whenever there is a further refrigeration machine which is operated at a higher temperature level and which alone dissipates the heat of liquefaction to the environment. The refrigeration set is in this case dependent on this refrigeration machine and in turn transfers its heat of liquefaction thereto. By way of example, it is possible for a standard cooling set to be connected upstream of a freezing set, in which case the two cooling sets may have different refrigerants or refrigerant mixtures.
[0013] If what are known as normal cooling points and what are known as freezing points are present inside a hypermarket or supermarket, these are generally supplied by means of separate refrigerant cycles; this therefore means that there are at least two refrigeration installations as described in DE-C 39 28 430.
[0014] The refrigeration installation or the evaporators arranged in the refrigeration consumers have to be defrosted at regular intervals, since frosting or icing of the evaporators leads to a reduction in the efficiency of the evaporators. One defrosting option is electrical defrosting, in which the evaporators are defrosted by means of electrical heaters arranged in and/or on them. However, this procedure leads to an undesirable increase in the consumption of electrical energy.
[0015] What is known as compressed gas defrosting is a recommended alternative to the electrical defrosting described above. In this case, compressed-gas lines are laid between the gas space of the collection vessel connected downstream of the liquefier and each evaporator or evaporator module, and refrigerant, which is preferably at a temperature of between 35 and 45° C., is fed from the collection vessel to the evaporators or evaporator modules via these compressed-gas lines. However, the installation outlay for this compressed-gas defrosting is relatively high, since either a separate compressed-gas line has to be provided for each evaporator or each evaporator module or, as is customary in the two-wire system, switching valves and a second set comprising the same refrigerant (mixture) are required. Furthermore, there is the possibility of defrosting by means of circulated air at temperatures above approx. 2° C.
SUMMARY OF THE INVENTION
[0016] It is an object of the present invention to provide a refrigeration installation of the generic type which in terms of investment and operating costs and also reliability has advantages over the refrigeration installations of the prior art.
[0017] To achieve this object, the invention proposes a refrigeration installation which is distinguished by the fact that
the expansion members are designed as modified expansion valves and/or as modified linear expansion machines or are assigned bypass lines, and each refrigeration consumer is assigned a modified linear compressor or a conventional compressor, which includes a bypass line, the modified expansion valve(s) and/or the modified linear expansion machine(s) and/or the modified linear compressor(s) having a working position which allows flow to pass through without a significant pressure drop.
[0021] Most linear compressors operate as oil-free cryogenic Stirling coolers at extremely low temperatures and extremely low powers, i.e. in cold-vapor compression. In cold-vapor compression, linear compressors have only been implemented for a few years and have hitherto not been deployed extensively. In the cooling sector, the applicant is only aware of one application, namely the use of a linear compressor in a domestic refrigerator. A drawback of linear compressors is that their production costs have hitherto been well above those of reciprocating-piston compressors driven in rotation, but of a similar order of magnitude to inverter compressors. Only in the 1960s were efforts made to exploit the advantages of linear compressors. The principle of friction-free mounting of the piston only dates from this time. Even so, it was only in the 1990s that improvements were made to the operational reliability, by virtue of reliable electronic reciprocating controllers. In this case, it was or is necessary in particular to ensure that for example fluctuating pressures do not lead either to the piston striking the cylinder head or to premature termination of the reciprocating operation at the top dead center, associated with an excessive damage volume and volumetric or energy drawbacks of re-expansion.
[0022] Linear compressors have the advantage of allowing continuously variable power control, which is realized by reciprocating control. Furthermore, they can be operated without oil. Furthermore, the condensate which is inevitably formed during defrosting operation does not cause any damage to them. Furthermore, they are superior in energy terms to oil-lubricating reciprocating piston compressors which are driven in rotation.
[0023] Although they are operated without oil, the oil-lubricated compressors which are driven in rotation are superior in energy terms. This results on the one hand from the efficient linear motor and on the other hand from the elimination of the mechanical losses, of which about 80% occur at the driving mechanism and about 20% at the piston. The piston of a linear compressor is mounted without contact and can be guided by what are known as flexible bearings, which allow axial mobility combined with radial rigidity. This ultimately means a spring combination of uncoiling and coiling springs which impart a rotary movement to the piston about its longitudinal axis in addition to its periodic translatory movement.
[0024] Since they do not have any sliding-contact bearings, linear compressors can be operated without oil. This absence of oil gives rise to numerous advantages. In the case of compressed-gas defrosting with condensation, the bearings, which have hitherto been relatively vulnerable, can no longer be damaged by liquid refrigerant (mixture). The formation of acid which is known when using lubricating oils and can lead to burn-out of the winding of built-in motors, has hitherto been more or less effectively avoided by the use of refrigerant dryers. These molecular sieve dryers can now be dispensed with unless the water content is so high that there is a risk precipitation of ice during the expansion. Irrespective of this, it is recommended that dirt filters be provided immediately upstream of the expansion valves or machines.
[0025] Linear compressors also have the advantage of not being damaged by the pumping of liquid, unlike other designs of compressor. The pumping of liquid is of relevance in particular after the end of a defrosting process, since at this time under certain circumstances condensate may still be present in the defrosted evaporators, and this condensate is sucked in by the compressor when it starts to operate again. However, it should expediently be ensured that liquid is pumped carefully. This means beginning with small reciprocating strokes, in order to limit the maximum power of the compressor during the conveying of liquid and to protect the working valves and reciprocating movement dampers. A design solution in which a disk valve as pressure valve replaces the cylinder head has also already been proposed; this leads to very high operational reliability.
[0026] Unlike the known refrigeration installations from the prior art, it is now possible to implement circuits in which the feed and discharge lines assigned to the refrigeration compressor(s) contain the liquid that is to be injected as well as the compressed gas of the compressor(s). Therefore, on the one hand there is no need for a central suction line, and on the other hand the compressors are no longer spatially separate from the consumer(s), but rather are located in the immediate vicinity of the refrigeration consumer(s).
[0027] The compressor sets which it has hitherto been necessary to provide in refrigeration installations can now be dispensed with, since each consumer is assigned at least one dedicated compressor. Therefore, each consumer can be controlled individually and, moreover, continuously by means of its own compressor. Unlike in the known procedures or refrigeration installations, this individual control can now take place irrespective of the temperature level in the return line, since the return or discharge line now no longer represents the suction line, the pressure of which is dependent on the evaporation temperature, which predetermines the temperature of the refrigeration consumers, but rather represents the pressure line.
[0028] If this is not impossible on account of other boundary conditions, it is possible, for example, for freezer cabinets to be temporarily used and operated as standard refrigerator cabinets and/or display shelves for fresh meat and at times for dairy products. In the simplest case, this changeover is effected by adjusting a temperature selection button on the refrigeration cabinet in question. Furthermore, a pressure line has a smaller diameter compared to the corresponding suction line and moreover does not require any insulation.
[0029] As has already been mentioned in the introduction, the invention also relates to two alternative methods for operating a refrigeration installation of the generic type in order to realize a compressed-gas defrosting method.
[0030] In this context, the first alternative of the method according to the invention for operating a refrigeration installation is distinguished by the fact that during the defrosting phase of the refrigeration consumer or at least one of the refrigeration consumers, the modified expansion valve(s) and the modified linear compressor(s) of the refrigeration consumer(s) which is/are to be defrosted is/are moved into the working position in which through-flow without a significant pressure drop is possible.
[0031] The second alternative of the method according to the invention for operating a refrigeration installation is characterized in that during the defrosting phase of the refrigeration consumer or at least one of the refrigeration consumers, the associated bypass lines are opened and the associated conventional expansion valve(s) and the associated conventional compressor(s) are taken out of operation.
[0032] The refrigeration installation according to the invention, the methods according to the invention for operating a refrigeration installation and further configurations of the refrigeration installation according to the invention and of the methods according to the invention will be explained in more detail on the basis of the exemplary embodiments illustrated in FIGS. 1, 2 and 3 .
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 shows a refrigeration installation;
[0034] FIG. 2 shows an alternative embodiment of a refrigeration installation; and
[0035] FIG. 3 shows another embodiment of a refrigeration installation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0036] FIG. 1 shows a refrigeration installation according to the invention, which is used to supply three refrigeration consumers V′, V″ and V′″. Of course, there may be any desired number of refrigeration consumers. The refrigerant or refrigerant mixture—referred to below simply as “refrigerant”—is fed to the above-mentioned refrigeration consumers via a (central) feed line 1 and lines 1 ′, 1 ″ and 1 ′″ which branch off from this feed line 1 .
[0037] According to the invention, either a modified expansion valve a, b or c is connected upstream of the evaporator of each refrigeration consumer V′, V″ and V′″ or
[0038] as illustrated in FIG. 2 —the upstream conventional expansion valve a′ has a bypass line 4 , represented by dashed lines. FIG. 2 shows, on the basis of the refrigeration consumer V′, by way of example, an alternative configuration of the refrigeration installation according to the invention to the embodiment illustrated in FIG. 1 . As an alternative to the modified expansion valves a, b and c illustrated in FIG. 1 , it is also possible to use modified linear expansion machines.
[0039] After expansion has taken place in the valves a, b and c or a′ described above, the expanded refrigerant is fed via the lines 2 ′, 2 ″ and 2 ′″ to the evaporators of the refrigeration consumers V′, V″ and V′″, in which it is evaporated.
[0040] The evaporated refrigerant is then fed back to the (central) return line 3 via the return lines 3 ′, 3 ″ and 3 ′″ by means of the modified linear compressors x, y and z. Instead of the modified linear compressors x, y and z illustrated in FIG. 1 , it is also possible to provide a conventional compressor x′ which has a bypass line 5 , illustrated by dashed lines; this embodiment of the refrigeration installation according to the invention is also illustrated in FIG. 2 .
[0041] If the refrigeration consumer V′ or its evaporator, for example, is to be defrosted, the modified linear compressor x and the modified expansion valve a are moved into the working position in which flow through the modified linear compressor x and the modified expansion valve a is possible without a significant pressure loss in the refrigerant. According to the invention, the warm refrigerant now passes out of the refrigeration consumers V″ and/or V′″, via the line 3 ′, through the opened, modified linear compressor x to the evaporator of the refrigeration consumer V′ and defrosts the latter. The refrigerant which has been cooled and possibly condensed as a result of the defrosting process is fed back to the (central) feed line 1 via the line 2 ′, the opened modified expansion valve a and the line 1 ′, and then passes back to the refrigeration consumers V″ and V′″ via the lines 1 ″ and 1 ′″.
[0042] If—as illustrated in FIG. 2 —bypass lines 4 and 5 are provided, the conventional expansion valve a′ and the conventional compressor x′ are taken out of operation and the refrigerant required to defrost the evaporator of the refrigeration consumer V′ passes via the lines 3 ′ and 5 to the evaporator of the refrigeration consumer V′ that is to be defrosted. After defrosting has taken place, the refrigerant is then fed back to the (central) feed line 1 via the lines 2 ′, 4 and 1 ′.
[0043] According to an advantageous configuration of the refrigeration installation according to the invention, the refrigeration consumers V′, V″ and/or V′″ can—as illustrated in FIG. 1 —be connected to the feed line 1 and the discharge line 3 by means of couplings, preferably by means of quick-acting couplings K, in particular by means of standardized quick-acting couplings.
[0044] In addition or as an alternative to the procedure illustrated in FIG. 1 , the refrigeration consumers V′, V″, V′″, . . . may also—as illustrated in FIG. 2 —be connected to one another in segments and directly, including the main lines 1 and 3 . In this context, it should be ensured that under certain circumstances consumers or liquefiers at a different level—i.e. for example cold stores which are arranged on different floors of a hypermarket—are connected to one another, although in this case direct coupling or connection is not possible.
[0045] The flexibility of the refrigeration installation according to the invention can be increased further by means of these above-described advantageous configurations of the refrigeration installation according to the invention.
[0046] Both methods according to the invention for operating a refrigeration installation now make it possible for one or more refrigeration consumers that are to be defrosted simultaneously to be defrosted by the other refrigeration consumer(s) which are in the cooling phase. This is done without the need for additional pipe networks and/or additional energy sources, as were required hitherto for compressed-gas defrosting.
[0047] As a refinement to the refrigeration installation according to the invention, it is proposed that
the refrigeration consumer or at least one of the refrigeration consumers has a dedicated closed refrigerant (mixture) cycle, the refrigerant (mixture) cycle(s) is/are operatively connected via at least one liquefier to the feed line and the discharge line, and the refrigerant (mixture) cycle(s) in each case has/have modified expansion valves and/or modified linear expansion machines or conventional valves with associated bypass lines and modified linear compressors or conventional compressors with associated bypass lines, the evaporator of a refrigeration consumer in each case being arranged higher than the liquefier of the refrigeration consumer.
[0052] FIG. 3 shows by way of example with reference to refrigeration consumer V′ the above-mentioned configuration of the refrigeration installation according to the invention.
[0053] In this case, the refrigeration consumer V′, V″ or V′″ as a dedicated refrigerant (mixture) cycle 6 , 7 , 8 and 9 , which is operatively connected via the liquefier E to the feed line 1 and the discharge line 3 . The refrigerant (mixture) cycle 6 , 7 , 8 and 9 has either a modified expansion valve a and a modified linear compressor x or a modified linear expansion machine, or else the conventional valve and/or the conventional expansion machine and the conventional compressor are assigned bypass lines, which are indicated by dashed lines in FIG. 3 .
[0054] Those line portions and components which form part of the refrigeration consumer itself are surrounded in FIG. 3 by the dot-dashed line. This may optionally include the feed line 1 and discharge line 3 .
[0055] In order now in defrosting operation to allow an automatic refrigerant (mixture) recirculation to be realized, it is necessary for the evaporator of the refrigeration consumer V′ to be arranged at a higher level than the heat exchanger E.
[0056] This configuration allows the flexibility of the refrigeration installation according to the invention to be increased significantly compared to refrigeration installations of the generic type, since this configuration of the refrigeration installation according to the invention allows the (retrospective) inclusion of further refrigeration consumers in the refrigeration installation assembly.
[0057] As has already been mentioned, in the refrigeration installations of the prior art, it is always necessary to provide at least two separate refrigerant (mixture) cycles if both normal cooling and freezing points or consumers are to be supplied with refrigeration. This problem is likewise eliminated by the refrigeration installation according to the invention, since now only one refrigerant (mixture) cycle needs to be provided.
[0058] The linear compressors that are to be provided are operated without oil. Therefore, the refrigeration installation according to the invention eliminates all the measures which have hitherto been required to separate off, recirculate, distribute and store the oil. Since transporting and distributing the oil within the pipe network is no longer of relevance, the individual lines or line sections can now be dimensioned exclusively on the basis of economic criteria.
[0059] The invention means that it is now no longer necessary to install what are known as combined refrigeration sets. Rather—at least in a relatively large area—it is possible for a large number of individual and if appropriate different refrigeration consumers to be linked into or removed from an existing system comprising liquid line, gas or pressure line and liquefier, if appropriate retrospectively. This is made possible in particular by virtue of the fact that it is possible to dispense with the above-described compressor sets of the combined refrigeration installations that have hitherto been required, since each refrigeration consumer now has its own compressor, which is adapted to the prevailing boundary conditions and specifics of the refrigeration consumer.
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A refrigerating system comprises at least one refrigerating consumer provided with at least one evaporator, at least one supply line and at least one withdrawal line which enable the coolant or the coolant mixture to be supplied to and/or withdrawn from the refrigerating consumer(s). Expansion elements are associated with the evaporator(s). The expansion elements are embodied as modified expansion valves and/or as modified linear expansion machines or the by-pass lines are associated therewith, and a modified linear compressor or a traditional compressor, which comprises a by-pass line is associated with each refrigerating consumer. The modified expansion valve(S) and/or the modified linear expansion machine(s) and/or the modified linear compressor(s) have a working position which enables a through-flow without a considerable drop in pressure.
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CROSS REFERENCE TO RELATED APPLICATIONS
The present application is a continuation application of U.S. patent application Ser. No. 11/209,870, which was filed on Aug. 23, 2005, which is assigned to the assignee of the present invention. The present application claims priority benefits to U.S. patent application Ser. No. 11/209,870.
TECHNICAL FIELD
The present invention relates in general to data processing systems, and in particular, to communications network devices referred to as blade servers.
BACKGROUND INFORMATION
The use of servers as devices within communications networks is well known in the art. A server is equipment that makes available file, database, printing, facsimile, communications or other services to client terminals/stations with access to the network the server serves. When the server permits client/terminal station access to external communications network it is sometimes known as a gateway. Servers are available in different sizes, shapes and varieties. Servers may be distributed throughout a network or they may be concentrated in centralized data centers.
Advances in centralized data processing centers have resulted in smaller form factors for server devices and an increase in the density of processing units, thereby reducing space requirements for computing infrastructure. One common form factor has been termed in the art a blade server, comprising a device built for vertically inserting into a chassis that can house multiple devices that share power and other connections over a common backplane, i.e., a blade center. Slim, hot swappable blade servers fit in a single chassis like books in a bookshelf—and each is an independent server, with its own processors, memory, storage, network controllers, operating system and applications. The blade server, also referred to simply as a blade, slides into a bay in the chassis and plugs into a mid- or backplane, sharing power, fans, floppy drives, switches, and ports with other blade servers. The benefits of the blade server approach will be readily apparent to anyone tasked with running down hundreds of cables strung through racks just to add and remove servers. With switches and power units shared, precious space is freed up—and blade servers enable higher density with far greater ease. With a large number of high-performance blade servers in a single chassis, blade technology achieves high levels of density.
Even though power consumption and device complexity per unit of processing power may actually decrease with a blade center, since the physical density of the computing devices has increased, the demands on power consumption for processing power and cooling have also intensified as overall computing power has increased. A blade center chassis has resources such as power and cooling that are shared by multiple components in the enclosure. A management module is present in each chassis which is responsible for managing all components within a chassis and the relationship between them. Each blade server is allocated a fixed amount of power or cooling capacity. If any blade server exceeds its allocation, it can force the entire chassis to exceed threshold values, which can, in turn, force the common power supply to shut down, causing other blade servers to be turned off. Another risk is that any blade server exceeding its allocation can cause other blade servers to shutdown due to temperatures exceeding their critical thresholds.
Probably, one of the most pressing problems associated with servers is manageability and particularly manageability as applied to chassis mounted servers. One aspect of manageability within this type of server relates to managing performance within the constraints of the available resources. Well-known in the art are management methods and their related system architectures for maintaining a sufficient level of computing power and aggregate data throughput in the face of highly fluctuating or deterministic service requests. Documented application server resource management methods aim to provide an optimum level of service for a given set of resources, subject to a certain demand of computing power; upon total utilization of available resources, the methods generally assume that the processing power is expandable ad infinitum, thus demanding additional computing infrastructure. However, certain instrinsic resource constraints on any given computing center location, such as available electrical power, space, and cooling, are finite and thus effectively limit further expansion of that infrastructure. Projects for expanding or duplicating an existing computing center often require significant corporate resources and carry an economic impact that goes well beyond the cost of the core computing infrastructure. As blade server performance values, such as processor speeds and bus clock frequencies, have increased dramatically, electrical power requirements within a single blade center have frequently reached constraining values, such that it may not be unusual that insufficient electrical power is available in a given chassis to simultaneously power on all blade servers present in the chassis. Furthermore, since a blade center chassis will often be dimensioned for future growth and expansion, newer, faster, power-hungry blade servers may need to be added to an existing chassis, which would normally exceed the rated values for power consumption.
All of the aforementioned factors indicate that power resources are a critical element in the economic success of a blade center. Therefore, a key aspect of manageability within this type of application server relates to allocating power resources, which has been solved by system architecture in past configurations by forcing individual blade servers to shutdown, or not permitting additional blade servers to power on. Clearly, a scenario where not all blade servers in a chassis may be powered on is economically detrimental for the operator of the blade center.
The computing resources within an individual blade server are unfortunately often wasted due to low utilization during normal operation, whereby the power allocated to (and consumed by) an individual blade server remains constant, usually at full power for all components. When determining server resources required for a target application, the administrator generally has to plan for the worst-case scenario. In one illustrative example, 80% of the time, an application may require some X amount of resources, comprising CPU cycles and physical memory. The other 20% of the time, the application may require 2× amount of those resources. In order to provide for that 20% of the time, the administrator was forced to dimension the server with 2× resources for the application to run on.
There are two ways to allocate power within a blade center chassis. In one case, illustrated in FIGS. 1 and 2 , a subset of blade servers can be allocated power sufficient to meet their maximum power consumption. This may result in underutilization of resources, as in the previous example, where 80% of the time only X amount of resources are utilized in a system providing 2× amount of resources. Alternatively, a subset of the blade servers can be allocated power for them to run at a lower percentage of their maximum power consumption, as illustrated in FIG. 3 . Since the power allocation is unenforceable, any spike in utilization by an application will result in an increase in power consumption, which can drive the aggregate power consumption over the capacity of the common power supply, catastrophically causing all servers in the chassis to fail or be shutdown.
In view of the above problems, a more efficient system and more reliable method is needed in the art for managing blade server utilization in an environment where electrical power is constrained.
SUMMARY OF THE INVENTION
The present invention addresses the foregoing needs by providing a mechanism for controlling the hardware resources on a blade server, and thereby limiting the power consumption of the blade server in an enforceable manner. The hardware resources that are controlled include the base frequency of the central processing unit (CPU) as well as power to individual banks of physical memory, for example dual-inline memory modules (DIMMs). The hardware resources are controlled to constrain the power required by the blade server, thereby reducing computing power of the blade server. The system and method of the present invention tunes the hardware resources in dependence on actual server utilization such that applications running on the blade server only have the allocated hardware resources available to them. Deactivated hardware resources are powered off and are so withheld from the operating system when they are not required. In this manner, power consumption in the entire chassis can be managed such that all blade servers can be powered on and operate at higher steady-state utilization. While there may be insufficient power and cooling available for operating all blade servers at 100% hardware resources, sufficient computing power may be achieved by operating all blade servers at some lower percentage of enabled hardware resources. Thus, the present invention provides a method for brokering allocated power among the blade servers in a blade center chassis and thereby distributing the available electrical power more effectively among a greater number of powered on blade servers. The utilization of the powered on resources in a blade center is also improved with the present invention.
One component of the present invention comprises hardware resource monitoring by a monitoring agent software running in the operating system that can monitor and report the utilization of physical memory and CPU cycles. The present invention leverages off standard protocols and interface support for throttling CPU speeds and hot plugging memory modules. A chassis power management software, running on a management module, serves as the resource broker within the blade center and may scale down the resources available to an application on a blade server to achieve some steady state threshold (SST), for example 90%. This has the effect of placing a limit on that server's power consumption, which is less than the value associated with the server running at full capacity. The chassis power management software may then allocate less power to the blade server than would be required for full-power operation. Through a shrewd combination of throttling the CPU and disabling memory DIMMs, the upper limit on power consumption is enforced. Even if the demands on the hardware resources from the application rise sharply or spike suddenly, the available hardware resources and power consumption remain constrained. When a monitoring agent software running on the blade server detects that utilization of a server resource is exceeding the SST and climbing towards a trending upwards threshold (TUT), a determination according to algorithm or policy will be made regarding the amount of additional blade server resources (CPU cycles or DIMMs) to make available to the operating system. The additional physical resources on the individual blade server will have a corresponding requirement for shared resources in the blade center chassis, i.e., electrical power and cooling capacity. The resource monitoring agent software will request that the management module, acting in the capacity of a resource broker for the common pool of unused power and cooling resources in the chassis, allocate sufficient power from the pool to the blade server for adjusting upwards the amount of server resources available to the application. Similarly, when the resource monitoring agent software detects that monitored values for server resources have fallen below a trending downwards threshold (TDT), it can remove resources from the operating system and power them down. The monitoring agent on the blade server then sends a notification to the management module that the blade server is thereby releasing its corresponding allocation of the shared resources back to the pool. For the purposes of controlling power consumed by the CPU, simple CPU utilization may represent values for the monitored threshold quantities SSU, TUT, and TDT, in one embodiment of the present invention. For the purposes of controlling power consumed by memory in another example of the present invention, percent of physical memory used, number of page faults, or a combination thereof may represent values for the monitored threshold quantities SSU, TUT, and TDT.
The present invention provides numerous advantagous benefits for manageability issues. The present invention allows the continued allocation to individual applications of a single server for ensuring that resources are available for meeting peak requirements during usage of the application. When an application is running below peak requirements, power consumption by individual servers is reduced by scaling down resources in use. When the aggregate total of resources required to support servers running at maximum utilization exceeds that which is available to them in the common pool, the present invention allows the servers to execute at levels tailored to their steady state requirements while ensuring that utilization spikes do not cause the resources available in the common pool to be exceeded.
An object of the present invention is to provide a mechanism for controlling the power allocated to individual blade servers in a blade center in an enforceable manner, whereby the control of the allocated power is retained by a management module in the blade center chassis.
Another object of the present invention is to increase the effective utilization of blade servers in a blade center chassis for a given computing workload at a given power consumption level.
Another object of the present invention is to provide the ability to use a combination of blade servers in a blade center that would otherwise exceed the maximum power rating for that blade center power supply.
Another object of the present invention is to provide for a common pool of reserve power that may be allocated to individual blade servers so that they may operate at power consumption levels tailored to their steady state requirements.
Still another object of the present invention is ensuring that utilization spikes do not cause reserve power resources in the common pool to be exceeded and preventing thereby a total loss of power in the blade center chassis, caused by overloading the common power supply or by exposure to excessive thermal loading.
The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
FIG. 1 illustrates a prior art scenario of resource allocation and utilization in a blade center;
FIG. 2 illustrates a prior art method of resource allocation in a blade center;
FIG. 3 illustrates a prior art method of resource allocation in a blade center;
FIG. 4 illustrates resource availability and utilization in a blade center in an embodiment of the present invention;
FIG. 5 illustrates power utilization in a blade center in an embodiment of the present invention;
FIG. 6 illustrates a timeline of power allocation for one blade server in an embodiment of the present invention;
FIG. 7 illustrates a schematic diagram of a blade center management subsystem;
FIG. 8 illustrates a front, top and right side exploded perspective view of a blade center chassis of the present invention;
FIG. 9 illustrates a rear, top and left side perspective view of the rear portion of the blade center chassis of the present invention;
FIG. 10 illustrates system components in one embodiment of the present invention;
FIG. 11 is a flow-chart of the power on portion of a power cycle process in one embodiment of the present invention; and
FIG. 12 is a flow-chart of the power allocation portion of a power cycle process in one embodiment of the present invention.
DETAILED DESCRIPTION
In the following description, numerous specific details are set forth such as specific word or byte lengths, etc. to provide a thorough understanding of the present invention. However, it will be obvious to those skilled in the art that the present invention may be practiced without such specific details. In other instances, well-known circuits have been shown in block diagram form in order not to obscure the present invention in unnecessary detail. For the most part, details concerning timing considerations and the like have been omitted inasmuch as such details are not necessary to obtain a complete understanding of the present invention and are within the skills of persons of ordinary skill in the relevant art.
Refer now to the drawings wherein depicted elements are not necessarily shown to scale and wherein like or similar elements are designated by the same reference numeral through the several views.
One prior art method for allocating power within a blade center chassis is illustrated in FIGS. 1 and 2 . A subset of blade servers can be allocated power sufficient to meet their maximum power consumption. This may result in underutilization of resources, as previously mentioned, where 80% of the time only X amount of resources are utilized in a system providing 2× amount of resources. Dimensioning a blade server according to the maximum power the blade server may satisfy the worst case operational scenario. However, the worst case scenario is also the infrequent case. Maximum utilization of hardware resources is commensurate with accrual of maximum benefit from ownership of the hardware. If a few of the systems in a blade center are operating at 20% utilization and the rest are turned off because of insufficient available power, clearly the customer is not deriving the maximum benefit of the hardware. In FIG. 2 , a static power allocation method, without managing resource utilization and availability, is shown for an exemplary blade center chassis with six blade servers installed. The power available in the chassis is evenly distributed according to the maximum power consumption of the blade servers present. In FIG. 2 , each blade server is rated at 300 W maximum power, and the power available in the chassis is 1400 W. Therefore blade servers 1 - 4 may be powered on under this allocation scheme consuming 1200 W of power, but blade servers 5 - 6 can not be powered on, even though 200 W of power remains available. In FIG. 1 , the inefficiency of this method is further illustrated in view of the percentage of available resources used by applications running on blade servers 1 - 4 , which operate at low utilization most of the time.
FIG. 3 illustrates an alternative prior art method for allocating power within the same blade center chassis as referred to in FIGS. 1 and 2 . This approach, where all of the systems operate unconstrained, introduces the possibility of spontaneously exceeding the power available to the systems. This may cause the power supplies to fail and all dependent systems to turn off immediately. A subset of the blade servers are allocated power for them to run at a lower percentage of their maximum power consumption, for example as illustrated in FIG. 3 , either at 200 W or 250 W per blade server, for a total of about 1350 W allocated power. Since the power allocation is unenforceable, any blade server may consume a maximum of 300 W anytime during operation. Any spike in utilization by applications may result in an increase in aggregate power consumption to over 1400 W, which exceeds what the common power supply can provide, potentially causing all servers in the chassis to catastrophically fail or to be shutdown. Thus the prior art power allocation method of FIG. 3 introduces both data reliability problems as well as the general problem of having inoperable systems with periods where the work allocated to them cannot be performed.
FIG. 4 illustrates enforced resource availability and utilization in a blade center in an embodiment of the present invention. For purposes of illustration, the same blade center chassis configuration as in the previous cases, FIGS. 1-3 , is referred to. However, in this case, the chassis 100 (see FIG. 10 ) is equipped with an enforceable power allocation system of the present invention, which conforms to the architecture embodied in FIGS. 11 and 12 . In FIG. 4 , each blade server 130 has a unique percentage of hardware resources, CPU 138 cycles and DIMMs 139 , enabled and powered on for use by the operating system 136 and applications 133 . In the steady state example illustrated in FIG. 4 , the average utilization of applications 133 running on a blade server 130 is kept balanced at 80% SST of the of resources made available to them by a enforceable power allocation process of the present invention, such as shown in one case by the process steps 1110 upon booting the operating system 136 . Through arbitration and brokering, as in the process 1250 , the percentage of available resources may be increased to maintain an 80% SST. In the case of work requests that result from a spike in application 133 resources, the hardware resources (CPU 138 , memory 139 ) presented to the operating system are constrained such that a utilization spike cannot cause the blade server 130 to exceed the power allocated to it. If utilization remains critically high, a given application may fail in a fashion that is particular to it. For example, determinate work requests may not be servicable during periods where utilization remains critically high.
FIG. 5 illustrates power utilization in a blade center in an embodiment of the present invention. For purposes of illustration, the same blade center chassis configuration (see FIG. 10 ) and enforceable power allocation scheme is referred to as in FIG. 4 . In FIG. 5 , the absolute values for power utilization are illustrated for each blade server 130 . Note that the average power utilization is kept just below the maximum power utilization at the enabled capacity on each blade server 130 . This illustrates the steady state performance of the method to regulate the enabled capacity of the present invention. In FIG. 5 , the aggregate power allocated is about 1200 W, comparable to the situation in FIGS. 1-3 . However, the present invention effectively mitigates the aforementioned risks of the prior art allocations methods in FIGS. 1-3 .
FIG. 6 illustrates a timeline of power allocation for one blade server 130 in an embodiment of the present invention. For purposes of illustration, the same blade center chassis configuration and enforceable power allocation scheme is referred to as in FIGS. 4 and 5 . However, FIG. 6 shows how transitions in power allocation over time are managed by the present invention. Before the time t 5 , the utilization remains below TUT for a power allocation of 200 W. At time t 5 , the utilization begins to rise and exceeds TUT for 200 W, such that arbitration for additional power occurs by a process 1250 , resulting in an additional 50 W of power allocated to the blade server 130 from the common pool. Thus from time t 5 to time t 12 , the power allocated to the blade server 130 is 250 W. At time t 12 , the utilization falls below TDT for a power allocation of 250 W, such that the blade server 130 frees up 50 W of power by a process 1210 which are brokered back into the common pool. After time t 12 , the power allocated is again 200 W and the utilization remains below TUT for 200 W. This example is illustrative for one blade server 130 undergoing two transitions to increase power 1250 then reduce power 1210 . In other embodiments of the present invention, the order and number of transitions may vary on each blade server 130 in each individual chassis 100 .
The system components and architecture for controlling power in a blade center chassis are illustrated in FIG. 10 . A blade center chassis 100 contains the following components relevant for controlling power: blade servers 130 which reside in the chassis slots 120 ; management modules (MM) 110 which may contain their own MM processor 117 ; a common power supply 140 and ventilators 150 ; and communication interfaces between these components 125 , 141 , 151 . In a blade center used to practice the present invention, the service processor (SP) 135 on a blade server 130 communicates, via the bidirectional interface 125 , with the MM processor 117 on the MM 110 . The MM 110 interfaces with the common power supply 140 via bus 141 and the ventilator 150 via a fan bus 151 . The bidirectional interface 125 between the MM processor 117 and the SP 135 , may be a multi-drop RS- 485 interface. Other interface protocols for 125 may be implemented. The control buses 141 , 151 may be I 2 C interfaces. On the blade server 130 , the SP 135 communicates with a BIOS 137 (basic input/output system) via System Management Interface SMI 131 for controlling the cycle frequency of the CPU 138 or power to the individual banks of DIMMs 139 . The BIOS 137 , which may be embodied by firmware stored on a flash memory device, may control the CPU 138 and DIMMs 139 via interface 132 , which may be SMI or another interface mechanism for controlling power consumption of CPU 138 and DIMMs 139 practiced within the scope of the present invention. A hardware resource monitoring agent software 134 communicates with the BIOS 137 and monitors the current state of CPU 138 cycles and DIMMs 139 . The resource monitoring agent 134 communicates with the SP 135 via interface 129 , which may be a kernel-mode driver in the operating system 136 or other communications interface. The operating system 136 and applications 133 comprise the computing load executed on the blade server 130 . The operating system 136 also executes the resource monitoring agent 134 and is responsible for providing any necessary kernel-mode driver routines or hardware interface management services.
FIG. 11 is a flow-chart of the power on portion 1110 of a power cycle process in one embodiment of the present invention. A MM 110 present in a blade center chassis 100 will be responsible for allocating and brokering power resources from a common power supply 140 among the blade servers 130 installed in the slots 120 in the chassis 100 . There are multiple blade servers 130 , each of which contain an SP 135 and a BIOS 137 , running an operating system 136 . At system initialization 1101 , the MM 110 determines the amount of power available in the chassis 100 by reading 1111 the vital product data (VPD) of the power supplies 140 in the chassis 100 , resulting in a maximum available power (MAP). For each blade server 130 , the SP 135 communicates with the BIOS 137 via SMI or other interface 131 to determine 1112 power consumption of each DIMM, capacity of each DIMM, CPU stepping levels, and CPU power consumption at each stepping level. Assuming that N blade servers 130 are present in the blade center chassis 100 , the MM 110 then allocates 1113 a fixed amount of power, in one example a value equivalent to MAP/N, to each blade server 130 . Alternate methods for determining how much power to provide 1113 each individual blade server 130 may be policy based, historical for the chassis 100 (maintained by the MM 110 ), historical for the blade server 130 (maintained by the blade server 130 ), determined by an external authority, or otherwise rule based in various other embodiments of the present invention. The difference between the MAP and the aggregate power allocated to each blade server 130 is the amount of power initially available in the common pool. The allocation of power 1113 by the MM 110 is executed by communicating a message from the MM processor 117 via interface 125 to the SP 135 . Based on the power consumption values determined in 1112 of memory DIMMs and the CPU at different stepping levels, the SP 135 informs the BIOS 137 via SMI or other interface 131 of the initial configuration that should be made available to the operating system 136 . This configuration comprises the number of DIMMs 139 to enable (and which specific modules thereof), and the throttling step level that the CPU 138 should be set to. The BIOS 137 then sets the appropriate configuration 1114 via interface 132 , and subsequently allows the operating system 136 to boot 1115 . After the blade server 130 is booted, the power allocation portion 1250 , 1210 of the power cycle begins 1201 , and repeats until the blade server 130 is shut down 1202 .
FIG. 12 is a flow-chart of the power allocation portion 1250 , 1210 of a power cycle process in one embodiment of the present invention. The power allocation events include transferring power from the common pool to a blade server 130 requiring a higher power allocation 1250 and transferring power from a blade server 130 utilizing a lower amount of power than currently allocated back to the common pool 1210 . The power cycle process ends 1202 after the blade server 130 is powered down 1216 .
When power allocation to blade server 130 is increased 1250 , an initial determination 1251 by the resource monitoring agent software 134 , which monitors CPU 138 and memory 139 utilization values SST and TUT, has been made that more resources are required. This determination 1251 may be result of a trend analysis, as illustrated in FIG. 6 , policy driven by an external entity, such as an administrator, rule-based, or derived from any combination of systematic criteria applied in individual embodiments of the present invention. In one case, the determination 1251 may result from considerations which balance the responsiveness of the system versus minimizing overall power consumption, such as the implementation of a control algorithm. In another case, a trend analysis across several power cycle processes 1110 , 1250 , 1210 may yield recorded historical threshold values for proactively triggering the determination 1251 . In yet another case, the determination 1251 may be schedule driven, where an adminstrator has recognized that spikes in application utilization will occur at a particular time and date, or where a regular pattern of utilization, such as normal business hours, require schedule-dependent resource management. When the resource monitoring software agent 134 has determined 1251 that more resources are required, the agent 134 issues a service request to the SP 135 to enable the additional hardware resources, CPU 138 cycles and/or DIMMs 139 . The SP 135 then calculates 1252 the additional power required to enable the requested hardware resources. The SP 135 then issues a request 1253 to the MM 110 which is responsible for brokering the power in the common pool for the additional amount of power. If the MM 110 , acting in its capacity as the resource broker under consideration of all applicable rules and policies, determines 1254 that more power should be made available to the requesting blade server 130 , the MM 110 will send a confirmation response 1255 back to the SP 135 indicating the actual amount of additional power that is allocated to the blade server 130 from the common pool. Note that the amount of power confirmed by the MM 110 may differ from, i.e. may be lower than, the amount requested by the SP 135 . The SP 135 will then confirm the directives of the MM 110 to the BIOS 137 via SMI 131 by requesting that the CPU 138 speed be stepped up, or additional memory DIMMs 139 be enabled as is appropriate. Note that the CPU step increase and number of additional DIMMs enabled may differ from the original request to the SP 135 by the BIOS 137 . The BIOS 137 then sets the hardware resources 1256 in compliance with the request by the SP 135 . Note that the MM 110 remains the governing authority for all increases in power allocated in the chassis 100 during brokering 1250 and must approve all requests for additional power from the blade servers 130 . The blade servers 130 must conform to the directives of the MM 110 and must be enabled to conform to the architecture requirements.
When power allocation to blade server 130 is decreased 1210 , a initial determination 1211 by the resource monitoring agent software 134 , which monitors CPU 138 and memory 139 utilization values SST and TDT, has been made that resources may be freed. This determination 1211 may be result of a trend analysis, as illustrated in FIG. 6 , policy driven by an external entity, such as an administrator, rule-based, or derived from any combination of systematic criteria applied in individual embodiments of the present invention. In one case, the determination 1211 may result from considerations which balance the responsiveness of the system versus minimizing overall power consumption, such as the implementation of a control algorithm. In another case, a trend analysis across several power cycle processes 1110 , 1250 , 1210 may yield recorded historical threshold values for proactively triggering the determination 1211 . In yet another case, the determination 1211 may be schedule driven, where an adminstrator has recognized that troughs in application utilization will occur at a particular time and date, or where a regular pattern of utilization, such as normal business hours, require schedule-dependent resource management. When the resource monitoring software agent 134 has determined 1211 that fewer resources are required, the agent 134 issues a service request to the SP 135 to disable some of the enabled hardware resources, CPU 138 cycles and/or DIMMs 139 . The SP 135 then calculates 1212 the additional power that can be made availabe to the common pool by disabling the requested hardware resources. The SP 135 then issues a request 1213 to the BIOS 137 via SMI 131 by requesting that the CPU 138 speed be stepped down, or additional memory DIMMs 139 be disabled as is appropriate. After the power consumption of the blade server 130 has been reduced 1213 by the BIOS, the SP 135 notifies 1214 the MM 110 that additional power has been made available to the common pool. The MM 110 , acting in its capacity as the resource broker under consideration of all applicable rules and policies, de-allocates the power for the blade server 130 and sends a confirmation response 1216 back to the SP 135 indicating the actual amount of additional power that has been allocated to the common pool from the blade server 130 . Note that the blade server 130 is required to relinquish power in a timely manner back to the common pool 1210 for the MM 110 to be able to broker future requests for more power 1250 from other blade servers 130 in the chassis 100 .
FIG. 7 is a schematic diagram of a blade center chassis management subsystem, showing engineering details of the individual management modules MM 1 -MM 4 , previously represented schematically by MM 110 , and showing engineering details of the individual components contained in previous schematic representations of blade center chassis 100 . Referring to this figure, each management module has a separate Ethernet link to each one of the switch modules SMI through SM 4 . Thus, management module MM 1 is linked to switch modules SMI through SM 4 via Ethernet links MM 1 -ENet 1 through MM 1 -ENet 4 , and management module MM 2 is linked to the switch modules via Ethernet links MM 2 -ENet 1 through MM 2 -ENet 4 . In addition, the management modules are also coupled to the switch modules via two well known serial I 2 C buses SM-I 2 C-BusA and SM-I2C-BusB, which provide for “out-of-band” communication between the management modules and the switch modules. Similarly, the management modules are also coupled to the power modules (previously represented schematically by 140 ) PM 1 through PM 4 via two serial I 2 C buses (corresponding to interface 141 ) PM-I 2 C-BusA and PM-I 2 C-BusB. Two more I 2 C buses Panel-I 2 C-BusA and Panel-I 2 C-BusB are coupled to media tray MT and the rear panel. Blowers BL 1 and BL 2 (previously represented schematically by 150 ) are controlled over separate serial buses Fan 1 and Fan 2 (corresponding to interface 151 ). Two well known RS 485 serial buses RS 485 -A and RS 485 -B are coupled to server blades PB 1 through PB 14 for “out-of-band” communication between the management modules and the server blades.
FIG. 8 illustrates a front, top and right side exploded perspective view of a blade server system, showing engineering details of the individual components contained in previous schematic representations of blade center chassis 100 . Referring to this figure, main chassis CH 1 houses all the components of the blade server system. Up to 14 processor blades PB 1 through PB 14 (or other blades, such as storage blades) are hot pluggable into the 14 slots in the front of chassis CH 1 . The term “server blade”, “blade server”, “processor blade”, or simply “blade” is used throughout the specification and claims, but it should be understood that these terms are not limited to blades that only perform “processor” or “server” functions, but also include blades that perform other functions, such as storage blades, which typically include hard disk drives and whose primary function is data storage.
Processor blades provide the processor, memory, hard disk storage and firmware of an industry standard server. In addition, they include keyboard, video and mouse (KVM) selection via a control panel, an onboard service processor, and access to the floppy and CD-ROM drives in the media tray. A daughter card may be connected via an onboard PCI-X interface and is used to provide additional high-speed links to various modules. Each processor blade also has a front panel with 5 LED's to indicate current status, plus four push-button switches for power on/off, selection of processor blade, reset, and NMI for core dumps for local control.
Blades may be “hot swapped”, meaning removed or installed in the power on state, without affecting the operation of other blades in the system. A blade server is typically implemented as a single slot card (394 mm×227 mm); however, in some cases a single processor blade may require two or more slots. A processor blade can use any microprocessor technology as long as it is compliant with the mechanical and electrical interfaces, and the power and cooling requirements of the blade server system.
For redundancy, processor blades have two signal and power connectors; one connected to the upper connector of the corresponding slot of midplane MP (described below), and the other connected to the corresponding lower connector of the midplane. Processor Blades interface with other components in the blade server system via the following midplane interfaces: 1. Gigabit Ethernet (2 per blade; required); 2. Fiber Channel (2 per blade; optional); 3. management module serial link; 4. VGA analog video link; 4. keyboard/mouse USB link; 5. CD-ROM and floppy disk drive (FDD) USB link; 6. 12 VDC power; and 7. miscellaneous control signals. These interfaces provide the ability to communicate with other components in the blade server system such as management modules, switch modules, the CD-ROM and the FDD. These interfaces are duplicated on the midplane to provide redundancy. A processor blade typically supports booting from the media tray CDROM or FDD, the network (Fiber channel or Ethernet), or its local hard disk drive.
A media tray MT includes a floppy disk drive and a CD-ROM drive that can be coupled to any one of the 14 blades. The media tray also houses an interface board on which is mounted interface LED's, a thermistor for measuring inlet air temperature, and a 4-port USB controller hub. System level interface controls consist of power, location, over temperature, information, and general fault LED's and a USB port.
Midplane circuit board MP is positioned approximately in the middle of chassis CH 1 and includes two rows of connectors; the top row including connectors MPC-S 1 -R 1 through MPC-S 14 -R 1 , and the bottom row including connectors MPC-S 1 -R 2 through MPC-S 14 -R 2 . Thus, each one of the 14 slots includes one pair of midplane connectors located one above the other (e.g., connectors MPC-S 1 -R 1 and MPC-S 1 -R 2 ) and each pair of midplane connectors mates to a pair of connectors at the rear edge of each processor blade (not visible in FIG. 8 ).
FIG. 9 is a rear, top and left side perspective view of the rear portion of the blade server system. Referring to FIGS. 8 and 9 , a chassis CH 2 houses various hot pluggable components for cooling, power, control and switching. Chassis CH 2 slides and latches into the rear of main chassis CH 1 .
Two hot pluggable blowers BL 1 and BL 2 (previously represented schematically by 150) include backward-curved impeller blowers and provide redundant cooling to the blade server system components. Airflow is from the front to the rear of chassis CH 1 . Each of the processor blades PB 1 through PB 14 includes a front grille to admit air, and low-profile vapor chamber based heat sinks are used to cool the processors within the blades. Total airflow through the system chassis is about 300 CFM at 0.7 inches H 2 O static pressure drop. In the event of blower failure or removal, the speed of the remaining blower automatically increases to maintain the required air flow until the replacement unit is installed. Blower speed control is also controlled via a thermistor that constantly monitors inlet air temperature. The temperature of the blade server system components are also monitored and blower speed will increase automatically in response to rising temperature levels as reported by the various temperature sensors.
Four hot pluggable power modules PM 1 through PM 4 (previously represented schematically by 140 ) provide DC operating voltages for the processor blades and other components. One pair of power modules provides power to all the management modules and switch modules, plus any blades that are plugged into slots 1 - 6 . The other pair of power modules provides power to any blades in slots 7 - 14 . Within each pair of power modules, one power module acts as a backup for the other in the event the first power module fails or is removed. Thus, a minimum of two active power modules are required to power a fully featured and configured chassis loaded with 14 processor blades, 4 switch modules, 2 blowers, and 2 management modules. However, four power modules are needed to provide full redundancy and backup capability. The power modules are designed for operation between an AC input voltage range of 200 VAC to 240 VAC at 50/60 Hz and use an IEC320 C14 male appliance coupler. The power modules provide +12 VDC output to the midplane from which all blade server system components get their power. Two +12 VDC midplane power buses are used for redundancy and active current sharing of the output load between redundant power modules is performed.
Management modules MM 1 through MM 4 (previously represented schematically by 110 ) are hot-pluggable components that provide basic management functions such as controlling, monitoring, alerting, restarting and diagnostics. Management modules also provide other functions required to manage shared resources, such as the ability to switch the common keyboard, video, and mouse signals among processor blades.
Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.
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A mechanism for controlling the hardware resources on a blade server, and thereby limiting the power consumption of the blade server is disclosed. The enforceable hardware resources that are controlled include the base frequency of the central processing unit (CPU) as well as power to individual banks of physical memory, for example dual-inline memory modules (DIMMs). The hardware resources are tuned in dependence on actual server utilization such that applications running on the blade only have the allocated hardware resources available to them. Deactivated hardware resources are powered off and are so ‘hidden’ from the operating system when they are not required. In this manner, power consumption in the entire chassis can be managed such that all server blades can be powered on and operate at higher steady-state utilization. The utilization of the powered on resources in a blade center is also improved.
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This application is a division of application Ser. No. 845,537, filed Mar. 28, 1986 now issued as U.S. Pat. No. 4,723,446.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to a device for measuring a displacement of a movable member relative to a fixed member, and more particularly to a device for measuring the displacement by using the electromagnetic induction phenomenon. More specifically, the present invention is concerned with a device for detecting a liquid level in a container by putting the electromagnetic induction phenomenon into practical use.
2. Description of the Prior Art
As one of the conventional liquid level detecting devices, there has been proposed such a device as disclosed in FIG. 1 of the attached drawings. The device "A" disclosed is of a so-called "variable resistance type" arranged in a container in which a liquid to be measured is contained.
The device "A" comprises a zig-zag resistor pattern "B" and an elongate conductive pattern "C" which are arranged in parallel and printed on a rectangular insulating base plate "D". The base plate "D" is fixed in the container to extend vertically. A float E is disposed about the base plate "D" so as to be vertically movable relative to the fixed base plate in accordance with a rise and fall of the level of the liquid in the container. Two conductive sliders "F 1 " and "F 2 " are carried by the float "E" with their leading ends slidably contacting with the two patterns "B" and "C", respectively. The two patterns "B" and "C" and the sliders "F 1 " and "F 2 " thus constitute a variable resistor the resistance of which changes in accordance with the vertical movement of the float "E", that is, in accordance with the fluctuation of the liquid level in the container. The zig-zag pattern "B" (viz., the measuring resistor) is connected to an electric power source "G" through a fixed resistor "H". The voltage fluctuation thus appearing between the measuring resistor "B" and the fixed resistor "H" due to the fluctuation of the liquid level is detected by a voltage detecting circuit "I" and the voltage fluctuation thus detected is treated by an indicating circuit "J" to indicate the amount of the liquid in the container.
However, the above-mentioned device "A" has suffered from the drawback that due to the mechanical contact between each slider "F 1 " or "F 2 " and the printed pattern "B" or "C", long use of the device induces remarkable wear of the measuring resistor "B" changing the original resistance value of the same. This causes erroneous measuring of liquid level. In the severest case, the measuring pattern "B" is broken because of the wear.
Furthermore, due to a friction inevitably produced between each slider "F 1 " or "F 2 " and the printed pattern "B" or "C", the upward or downward movement of the float "E" is not smoothly carried out thereby causing erroneous indication of liquid level. This undesirable phenomenon becomes severer when foreign matter gets in between the sliders and the printed patterns accidentally.
SUMMARY OF THE INVENTION
It is therefore an essential object of the present invention to provide a measure for solving the above-mentioned drawbacks.
It is another object of the present invention to provide a device for measuring a displacement of a movable member relative to a fixed member by practically using electromagnetic induction phenomenon.
It is still another object of the present invention to provide a device for detecting a liquid level in a container by putting the electromagnetic induction phenomenon into practical use.
According to the present invention, there is provided a device for measuring a displacement of a movable member relative to a fixed member, the device comprising an AC signal source, a first coil mounted to the fixed member and including first and second coil sections which are electrically connected and coaxially aligned along a common axis so that the first coil has a first extreme end constituting an outside end of the first coil section, a middle portion defined between respective inside ends of the first and second coil sections and a second extreme end constituting an outside end of the second coil section, a second coil coaxially disposed in the first coil and mounted to the fixed member so as to establish a magnetic coupling with first coil, one of the first and second coils being connected to the AC signal source to receive an AC signal, a short circuit ring fixed for movement with the movable member, the short circuit ring being axially disposed about the first coil so as to establish a magnetic coupling with the first coil and second coils sand constructed to consume magnetic energy, a float connected to the short circuit ring to cause the short circuit ring to remain on top of a fluid, and means connected to the other of the first and second coils for detecting a change in electromagnetic induction between the first coil and the second coil caused by the short circuit ring and for providing an information signal which is representative of the change, wherein the winding density of each of the first and second coil sections of the first coil is gradually decreased from the outside end to the inside end thereof, and the winding density of the second coil is substantially even throughout its length.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the present invention will become apparent from the following description when taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a sectional view of a prior art liquid level detecting device as described hereinabove, with some control circuits connected thereto;
FIG. 2 is a diagramatically illustrated circuit of a liquid level detecting device of a first embodiment of the present invention, with several control circuits connected thereto;
FIG. 3 is a sectional view of the liquid level detecting device of the first embodiment;
FIG. 4 is the circuit of the liquid level detecting device of the first embodiment with some portions symbolically illustrated;
FIGS. 5a-d are a chart showing various signal forms appearing at given portions of the circuit of FIG. 2;
FIG. 6 is a graph showing the characteristic of output of the liquid level detecting device of the first embodiment;
FIG. 7 is a diagramatically illustrated circuit of a liquid level detecting device of a second embodiment;
FIG. 8 is a view similar to FIG. 7, but showing a third embodiment;
FIG. 9 is a view similar to FIG. 3, but showing a fourth embodiment;
FIG. 10 is a view similar to FIG. 7, but showing a fifth embodiment;
FIG. 11 is a graph showing the characteristic of output of the device of the fifth embodiment;
FIG. 12 is a view similar to FIG. 7, but showing a sixth embodiment;
FIG. 13 is a graph showing the characteristic of output of the device of the sixth embodiment;
FIG. 14 is a view similar to FIG. 2, but showing a seventh embodiment of the present invention;
FIG. 15 is a sectional view of a liquid level detecting device of the seventh embodiment;
FIG. 16 is a graph showing the characteristic of output of the device of the seventh embodiment;
FIG. 17 is a view similar to FIG. 7, but showing an eighth embodiment of the invention;
FIG. 18 is a view similar to FIG. 7, but showing a ninth embodiment;
FIG. 19 is a view similar to FIG. 15, but showing a tenth embodiment of the invention;
FIG. 20 is a view similar to FIG. 19, but showing an eleventh embodiment of the invention;
FIG. 21 is a view similar to FIG. 2, but showing a twelfth embodiment of the invention;
FIG. 22 is a sectional view of a liquid level detecting device of the twelfth embodiment;
FIG. 23 is a graph showing the characteristic of output of the device of the twelfth embodiment;
FIGS. 24a-i are a chart showing various signal wave forms appearing at given portions of the circuit of FIG. 21;
FIG. 25 is a circuit of a liquid level detecting device of a thirteenth embodiment of the invention; and
FIG. 26 is a view similar to FIG. 22, but showing a fourteenth embodiment of the invention;
FIGS. 27 and 28 show modification of the coil arrangements of the first embodiment shown in FIG. 3; and
FIGS. 29 and 30 show modification of the coil arrangements of the tenth embodiment shown in FIG. 19.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 2 to 6, especially FIG. 2, there is shown an induction type liquid level detecting device 10A of a first embodiment of the present invention with several control circuits associated therewith.
In FIG. 2, denoted by numeral 11 is an AC signal source which supplies both a first coil (or exciting coil) 122 and a detection control signal generating circuit 13 with an AC signal "a" as depicted by FIG. 5a. It is to be noted that the frequency of the AC signal "a" (FIG. 5a) is so determined that elements (such as, operational amplifier and the like) constituting an after-mentioned amplification circuit 14 can exhibit their normal performances. More particularly, the frequency can be held at a low level so long as an undesirable resonance phenomenon due to stray capacitance is avoided. In the disclosed embodiment, the frequency is set at 1 KHz. By receiving the AC signal "a" (FIG. 5a) from the AC signal source 11, the circuit 13 issues a pulse signal "c", as shown in FIG. 5c, which is synchronous with the AC signal "a". Denoted by numeral 14 is a detecting circuit which comprises an amplifying circuit 141 and an analogue switch 142.
The amplifying circuit 141 amplifies the output signal "b" (FIG. 4b) issued from the induction type liquid level detecting device 10A proper which will be described hereinafter in detail. The analogue switch 142 treats the amplified signal with reference to the detection control signal "c" (FIG. 4c) issued from the detection control signal generating circuit 13. Denoted by numeral 15 is a filter circuit, 16 is a voltage detecting circuit and 17 is an indicating circuit. The signal "d" (FIG. 4d) treated by the detecting circuit 14 is smoothed by the filter circuit 15, then detected by the voltage detecting circuit 16 and thereafter treated by the indicating circuit 17 to indicate the amount of the liquid in the container.
The induction type liquid level detecting device 10A will be described in detail below.
As will be seen from FIG. 3, the device 10A comprises generally the first coil 122 (exciting coil) wound on an elongate core 121 (which will be referred to as a first coil bobbin, hereinafter), a second coil 124 wound on a hollow plastic case 123 (which will be referred to as a second coil bobbin, hereinafter) within which the first coil 122 and thus the first coil bobbin 121 are coaxially housed, and a short circuit ring 126 of coil mounted to a float 125. The float 125 is arranged to move smoothly upward and downward in response to the rise and fall of the liquid level in the liquid container. For achieving the smooth movement of the float 125 relative to the coil-carrying second coil bobbin 123, the float 125 has a guide bore (no numeral) through which the second coil bobbin 123 passes with an adequate clearance therebetween.
As will be understood from FIG. 2, the first coil 122 comprises an upper (or first) coil section 1221 the winding density of which is gradually decreased from the top portion of the first coil bobbin 121 to the middle portion of the same, and a lower (or second) coil section 1222 the winding density of which is gradually increased from the middle portion of the first coil bobbin 121 to the lower portion of the same. If desired, the winding of the coil sections on the bobbin may be made stepwisely or linearly so long as the winding density inclination is established. These two coil sections 221 and 1222 are so arranged as to generate, upon electric energization, respective magnetic fluxes which advance in mutually opposed directions. For achieving this, the lower end of the first coil section 1221 is connected to the lower end of the second coil section 1222, as shown. The upper end of the second coil section 1222 is earthed. The upper end of the first coil 122 is connected to the AC signal source 11.
The second coil 124 (measuring coil) is thus magnetically coupled with to the first coil 122. The winding density of the coil 124 is even throughout the axial length thereof as is seen from FIG. 2.
As will be seen from FIG. 3, the short circuit ring 126 on the float 125 is coaxially arranged with respect to the common axis of the first and second coils 122 and 124, establishing a magnetical coupling with these coils 122 and 124.
In the following, operation of the induction type liquid level detecting device 10A will be described with reference to FIG. 4.
For ease of understanding, let us suppose that the first coil 122 serving as an exciting coil comprises a series of small coils L 1 , L 2 and L 3 of different number of turns (which series corresponds to the upper coil section 1221) and another series of small coils L 1 ', L 2 ' and L 3 ' of different number of turns (which series corresponds to the lower coil section 1222), and let us suppose that the magnetic fluxes produced by these small coils L 1 , L 2 , L 3 , L 1 ', L 2 ' and L 3 ' are designated by φ 1 , φ 2 , φ 3 , -φ 1 , -φ 2 and -φ 3 , respectively.
When, as is seen in FIG. 4, the short circuit ring 126 comes to a position facing the small coil L 2 of the upper coil section 1221 due to fluctuation of the liquid level in the container, the small coils (each having an equal number of turns) constituting the second coil 124 are forced to generate respective induced electromotive forces, which are: ##EQU1## wherein: n: the number of turns of each coil.
Because the output of the second coil 124 is represented as a sum of the induced electromotive forces of these small coils, the output is represented by the next equation: ##EQU2##
As will be understood from this equation, when the short circuit ring 126 assumes the above-mentioned position, the magnetic energy of the small coil L 2 is consumed by the short circuit ring 126 thereby to prevent generation of magnetic flux of the small coil L 2 with a result that only the induced electromotive force e 2 ' produced by the small coil L 2 ' is outputted from the second coil 2. In this case, as is shown by a solid curved line in FIG. 5b, the electromotive force e 2 ' has the same phase as the AC signal "a" (FIG. 5a) and has a crest value which corresponds to the liquid level then established.
It is to be noted that the signal wave forms illustrated by the dot-dash line and the broken line in FIG. 5b are presented for showing a fact that even when the short circuit ring 126 moves only within the range of the upper coil section 1221, the crest value of the induced electromotive force outputted from the second coil 124 changes depending on what magnetic flux of the upper coil section 1221 is shortened by the short circuit ring 126. It is further to be noted that the signal wave form illustrated by the dot-dot-dash line in FIG. 5b shows the induced electromotive force which is outputted from the second coil 124 when the short circuit ring 126 assumes a position within a range of the lower coil section 1222. As is seen from this wave form chart, the phase of the output (dot-dot-dash line) is reversed to that of the output produced when the short circuit ring 126 is located within the range of the upper coil section 1221.
As is understood from the foregoing description, the crest value of the output signal from the second coil 124 changes in accordance with the position of the short circuit ring 126, that is, in accordance with the liquid level in the liquid container. Furthermore, the phasic relation of the output signal from the second coil 124 to the AC signal "a" (FIG. 5a) changes by 180 degrees depending on whether the short circuit ring 126 is within the range of the upper coil section 1221 or the lower coil section 1222.
The induced electromotive force outputted from the second coil 124 is detected by the detecting circuit 14 on the basis of the detection control signal "c" (FIG. 5c) outputted from the detection control signal generating circuit 13, and from the detecting circuit 14, there is outputted a voltage signal "d" with the characteristic as shown by FIG. 5d. The voltage signal "d" is applied to the smoothing circuit 15 to be smoothed (see the flat voltage lines designated by +V, +V' and -V in FIG. 5d). Due to the above-mentioned unique arrangement of the first coil 122, the DC voltage thus outputted from the smoothing circuit 15 shows such the characteristic as shown in FIG. 6 which shows the output voltage relative to the position of the liquid level. The value of the DC voltage is read by the voltage detecting circuit 16 and treated by the indicating circuit 17 to indicate the amount of the liquid in the container.
Although, in the first embodiment 10A, the second coil bobbin 123 is employed for winding thereon the second coil 124, the present invention is not limited to such an arrangement. That is, if desired, the second coil 124 may be wound directly on the first coil 122 without using the second coil bobbin. Furthermore, the positional relation between the first coil 122 and the second coil 124 may be reversed. That is, in this reversed arrangement, the second coil 124 is wound on the first coil bobbin 121 and the first coil 122 is wound on the second coil bobbin 123 in which the second coil 124 is installed. Examples of such modifications are shown in FIGS. 27 and 28.
Referring to FIG. 7, there is shown a circuit of a liquid level detecting device of a second embodiment 10B of the present invention. In this second embodiment, unlike the case of the first embodiment, the upper and lower coil sections 1221 and 1222 are connected in parallel with each other. That is, the inside ends of the upper and lower coil sections 1221 and 1222 are connected and earthed. The parts identical to those of the first embodiment 10A are denoted by the same numerals in the drawing, and explanation of them will be omitted.
Referring to FIG. 8, there is shown a circuit of a liquid level detecting device 10C of a third embodiment of the invention. As will be seen from this drawing, the exciting coil connected to the AC signal source 11 is a coil identical to the second coil 124 of the first embodiment 10A, while the measuring coil is a coil identical to the first coil 122 of the first embodiment.
Referring to FIG. 9, there is shown a liquid level detecting device 10D of a fourth embodiment of the invention. In this embodiment, a metal ring 126' constructed of for example aluminium or the like is used in place of the short circuit ring 126 of coil employed in the above-mentioned embodiments. The metal ring 126' consumes the magnetic energy on the principle of eddy-current loss. As the short circuit ring 126, a ring constructed of magnetic powder-impregnated plastic is also usable.
Referring to FIG. 10, there is shown a circuit of a liquid level detecting device 10E of a fifth embodiment of the invention. In this embodiment, the lower portion of the device is bent as shown. With this, the output from the smoothing circuit 15 shows the characteristic as shown in the graph of FIG. 11. That is, the left section of the output characteristic curve at which the changing rate of output is quite small can be deleted, so that the detecting ability of the device at the time when the liquid is small is improved.
Referring to FIG. 12, there is shown a circuit of a liquid level detecting device 10F of a sixth embodiment of the invention. In this embodiment, a rectangular frame-like core 121' is employed. The first coil 122 (that is, exciting coil) is wound on one bobbin portion of the core 121' and the second coil 124 (that is, measuring coil) is wound on the other bobbin portion to establish a closed magnetic circuit. With this arrangement, it is possible to solve a rapid fluctuation of the magnetic field which would occur, due to permeability, at the extreme ends of the detecting range. Thus, as is shown by the graph of FIG. 13, the curve of the output characteristic shows at both ends of the detecting range such characteristic as shown by the solid lines. That is, undesirable U-turn phenomenon depicted by the broken lines can be solved. Thus, in the sixth embodiment, wider detecting range is provided as compared with the first embodiment.
Referring to FIGS. 14 and 15, there is shown a liquid level detecting device 10G of a seventh embodiment. This device 12G is substantially the same as that of the first embodiment 10A except for several parts which will be described hereinafter. Thus, the substantially same parts as those of the first embodiment 10A will be denoted by the same numerals and detailed description of them will be omitted. In the seventh embodiment, two additional coils 1221a and 1222a of increased number of turns are further employed, one being connected to the upper end of the upper coil section 1221 and the other being connected to the lower end of the lower coil section 1222. As is understood from FIG. 14, the winding direction of each additional coil 1221a or 1222a is equal to hat of the associated coil section 1221 or 1222. As is seen from FIG. 15, these additional coils 1221a and 1222a are housed in upper and lower extensions 123a of the second coil bobbin 23, respectively. Preferably, the extensions are formed to have grooves, as shown.
Because of the provision of the additional coils 1221a and 1222a, the output from the smoothing circuit 15 has such a characteristic as shown by the solid curve in FIG. 16. For comparison, the output curve of the first embodiment 10A is also shown by dot-dot-dash line. As is understood from these curves, the detecting range of the seventh embodiment 10G is wider than that of the first embodiment 10A.
Referring to FIG. 17, there is shown an eighth embodiment 10H of the invention, which is substantially the same as the second embodiment 10B (see FIG. 7) except for the two additional coils 1221a and 1222a. That is, in the eighth embodiment 10H, the additional coils 1221a and 1222a are connected to the upper and lower coil sections 1221 and 1222 of the first coil 122 in the same manner as the seventh embodiment 10G.
Referring to FIG. 18, there is shown a ninth embodiment 10I of the invention, which is substantially the same as the third embodiment 10C (see FIG. 8) except for the two additional coils 1221a and 1222a. As is understood from the drawing, in the ninth embodiment, the two additional coils 1221a and 1222a are connected to the upper and lower coil sections 1221 and 1222 of the measuring coil.
Referring to FIG. 19, there is shown a tenth embodiment 10J of the invention, which is substantially the same as the fourth embodiment 10D of FIG. 9 except for the two additional coils 1221a and 1222a connected to the exciting coil 122. The coil arrangements may also be modified, as previously discussed, as shown in FIGS. 29 and 30.
Referring to FIG. 20, there is shown an eleventh embodiment 10K of the invention, which is a modification of the tenth embodiment 10J. That is, in the eleventh embodiment, a cylindrical case 127 is employed for receiving therein a detector proper which is substantially identical to the device of the tenth embodiment 10J. The case 127 is formed with a suitable number of holes (no numerals) for, when mounted in a liquid container, providing a fluid communication between the interior of the case 127 and the exterior of the same. The case 127 is formed with upper and lower stoppers 1271 and 1272 for suppressing extreme movement of the float 125.
Referring to FIGS. 21 and 22, there is shown an induction type liquid level detecting device 10L of a twelfth embodiment of the invention.
In FIG. 21, denoted by numeral 18 is a first AC signal source and 19 is a second AC signal source. The first AC signal source 18 supplies both a main exciting coil 202 (or first coil) of the induction type liquid detecting device 10L and a first detection control signal generating circuit 21 with an AC signal "a" as shown in FIG. 24a. The second AC signal source 19 supplies both an auxiliary exciting coil 204 (or third coil) of the device 10L and a second detection control signal generating circuit 22 with an AC signal "c" as shown in FIG. 24c. It is to be noted that the frequencies of the AC signals "a" and "c" are so determined that elements (such as operational amplifier or the like) constituting after-mentioned amplifying circuits 251 and 261 can exhibit their normal performances. More particularly, the frequencies can be determined to low levels so long as an undesirable resonance phenomenon due to stray capacitance is avoided. In the disclosed twelfth embodiment 10L, the frequency of the AC signal "a" is set at 1 KHz, while the frequency of the AC signal "c" is set at 6 KHz. By receiving the AC signal "a", the first detection control signal generating circuit 21 issues a pulse signal "b" (FIG. 24b) of detection control which is synchronous with the AC signal "a" (FIG. 24a). By receiving the AC signal "c" (FIG. 24c), the second detection control signal generating circuit 22 issues a pulse signal "d" (FIG. 24d) of detection control which is synchronous with the AC signal "c". Denoted by numeral 23 is a low-pass filter which receives an output signal "e" (shown in FIG. 24e) from the device proper 10L and deletes from the signal "e" a high frequency component corresponding to the AC signal "c". Thus, a signal "f" having such characteristic as shown in FIG. 24f is outputted from the low-pass filter 23. Denoted by numeral 24 is a high-pass filter which receives the output signal "e" of the device proper 10L and deletes from the signal "e" a low frequency component corresponding to the AC signal "a". Thus, a signal "g" having such a characteristic as shown in FIG. 24g is outputted from the high-pass filter 24. Denoted by numeral 25 is a first detection circuit which comprises an amplifying circuit 251 for suitably amplifying the output signal "f" from the low-pass filter 23 and an analogue switch 252 for detecting the amplified output signal "f" in accordance with the detection control signal "b" issued from the first detection control signal generating circuit 21. Denoted by numeral 26 is a second detection circuit which comprises an amplifying circuit 261 for suitably amplifying the output signal "g" from the high-pass filter 24 and an analogue switch 262 for detecting the amplified output signal "g" in accordance with the detection control signal "d" issued from the second detection control signal generating circuit 22. Denoted by numerals 27 and 28 are first and second smoothing circuits which respectively smooth the output signal "h" (see FIG. 24h) from the first detection circuit 25 and the output signal "i" (see FIG. 24i) from the second detection circuit 26.
Denoted by numerals 29 and 30 are first and second voltage detecting circuits. The first voltage detecting circuit 29 detects the value of the DC voltage signal "h'" (see the line h' in FIG. 24h) outputted from the first smoothing circuit 27, while the second voltage detecting circuit 30 detects the value of the DC voltage signal "i'" (see the line i' in FIG. 24i) outputted from the second smoothing circuit 28. Denoted by numeral 31 is an indication control circuit which permits transmission of output of the second voltage detecting circuit 30 to an after-mentioned secondary indicator 322 only when the voltage value of the voltage signal "h'" from the first smoothing circuit 27 is lower than a predetermined value corresponding to the upper limit (see the point L o in the graph of FIG. 23) of liquid level detecting range which is determined when the associated liquid container contains small amount of liquid therein. That is, only when the voltage value of the voltage signal "h'" is lower than the predetermined value, the voltage value of the voltage signal "i'" from the second smoothing circuit 28 is treated by the secondary indicator 322. Denoted by numeral 32 is a double function indicator which comprises a primary indicator 321 for representing in bar-graphical fashion the output data (viz., the voltage of the voltage signal "h'") issued from the first voltage detection circuit 29 and the above-mentioned secondary indicator 322 for representing in digital fashion the output data (viz., the voltage of the voltage signal "i'") issued from the second voltage detection circuit 30 through the indication control circuit 31.
In the following, the induction type liquid level detecting device 10L will be described in detail.
As will be seen from FIGS. 21 and 22, the device 10L comprises generally the primary exciting coil (or first coil) 202 wound on a first coil bobbin 201, an auxiliary exciting coil (or third coil) 204 wound on a hollow plastic inner case (or third coil bobbin) 203 (see FIG. 22) in which the primary exciting coil 202 is coaxially disposed, a measuring coil (or second coil) 206 wound on a hollow plastic outer case (second coil bobbin) 205 (see FIG. 22) in which the auxiliary exciting coil 204 is coaxially disposed, and a short circuit ring 208 of coil fixed to a float 207 which moves upward and downward in response to the rise and fall of liquid level in the liquid container.
The primary exciting coil 202 has a length sufficiently enough for covering the liquid level detecting range and comprises upper and lower coil sections (or first and second coil sections) 2021 and 2022 which are connected in series and wound on the first coil bobbin 201 extending vertically. Similar to the afore-mentioned embodiments, the winding density of the upper coil section 2021 is gradually decreased from the upper portion of the first coil bobbin 201 to the middle portion of the same, and the winding density of the lower coil section 2022 is gradually increased from the middle portion of the bobbin 201 to the lower portion of the same. The upper and lower coil sections 2021 and 2022 are so arranged as to generate, upon electric energization, respective magnetic fluxes which advance in the mutually opposed directions. The primary exciting coil 202 is connected to the first AC signal source 18.
The auxiliary exciting coil 204 has a length of about one third of that of the primary exciting coil 202 and is wound on a lower portion of the third coil bobbin 203 (see FIG. 22). The auxiliary exciting coil 204 comprises upper and lower coil sections (or third and fourth coil sections) 2041 and 2042 which are connected in series. Similar to the primary exciting coil 202, the winding density of the upper coil section 2041 is gradually decreased from the upper end of the auxiliary exciting coil 204 to the middle portion of the same, and the winding density of the lower coil section 2042 is gradually increased from the middle portion of the auxiliary exciting coil 204 to the lower end of the same. The upper and lower coil sections 2041 and 2042 are so arranged as to generate, upon electric energization, respective magnetic fluxes which advance in the mutually opposed directions. The auxiliary exciting coil 204 is connected to the second AC signal source 19.
The measuring coil 206 has a length substantially equal to the primary exciting coil 202 and is wound on the second coil bobbin 205. The winding density of the measuring coil 206 is even throughout the length thereof, as is understood from FIG. 21. Thus, the measuring coil 206 is magnetically coupled with both the primary and auxiliary exciting coils 202 and 204.
As is seen from FIG. 22, the short circuit ring 208 is coaxially disposed on the float 207 which is movable along the length of the second coil bobbin 205 in response to the fluctuation of the liquid level in the container. Thus, between the short circuit ring 208 and each of the primary exciting coil 202, the auxiliary exciting coil 204 and the measuring coil 206, there is established a magnetic coupling.
In the following, operation of the liquid level detecting device 10L having the above-mentioned arrangement will be described.
First, the description will be commenced with respect to a condition wherein the liquid level is relatively high, that is, the container contains a large amount of liquid therein. In this condition, the short circuit ring 208 assumes a position to face a part of the upper coil section 2021 of the primary exciting coil 202, as is shown in FIGS. 21 and 22. Thus, for the reason which has been explained in the first embodiment 10A, only the magnetic flux generated by a part of the lower coil section 2022 (viz., a counterpart of the part of the upper coil section 2022 to which the short circuit ring 208 faces) works to make the measuring coil 206 output the induced electromotive force. It is to be noted that, in this condition, the auxiliary exciting coil 204 does not take part in generation of the induced electromotive force due to absence of the short circuit ring 208. Accordingly, when the liquid level in the liquid container is relatively high, the measuring coil 206 outputs an induced electromotive force of the characteristic as depicted by the left-half of the wave-form shown in FIG. 24e. That is, the induced electromotive force has a phase equal to that of the AC signal "a" issued from the first AC signal source 18 and has a crest value determined in accordance with the distance from the middle portion of the primary exciting coil 202 to the liquid level in the liquid container.
Second, the description will be directed to a condition wherein the liquid level is relatively low, that is, the container contains only a small amount of liquid therein. In this condition, the short ring 208 assumes a position to face both the lower coil section 2022 of the primary exciting coil 202 and the auxiliary exciting coil 204. Thus, a magnetic flux generated by a part of the upper coil section 2021 (viz., a counterpart of the part of the lower coil section 2022 to which the short circuit ring 208 faces) of the primary exciting coil 202 and another magnetic flux generated by either one of upper and lower coil sections 2041 and 2042 work to make the measuring coil 206 output the induced electromotive force. Accordingly, when the liquid level in the liquid container is relatively low, the measuring coil 206 outputs an induced electromotive force of the characteristic as depicted by the right-half of the wave-form shown in FIG. 24e. That is, the induced electromotive force thus generated is a sum of the induced electromotive force which has a phase equal to that of the AC signal "a" issued from the AC signal source 18 and has a crest value determined in accordance with the distance from the middle portion of the primary exciting coil 202 to the liquid level in the liquid container and the other induced electromotive force which has a phase equal to that of the AC signal "c" issued from the second AC signal source 19 and has a crest value determined in accordance with the distance from the middle portion of the auxiliary exciting coil 204 (that is, the middle portion defined between the upper and lower coil sections 2041 and 2042) to the liquid level in the liquid container.
The induced electromotive force "e" (see FIG. 24e) thus outputted from the measuring coil 206 is applied to the low-pass filter 23 and the high-pass filter 24. As is seen from the graph of FIG. 24f, upon receiving the force "e", the low-pass filer 23 outputs a voltage signal "f" the phase of which is synchronous with that of the AC signal "a" from the first AC signal source 18 and the crest value of which is determined in accordance with the liquid level in the liquid container. (It is to be noted that the phasic relation of the voltage signal "f" relative to the AC signal "a" changes by 180 degrees depending on whether the short circuit ring 208 is within the range of the upper coil section 2021 or the lower coil section 2022. While, the high-pass filter 24 outputs, only when the liquid level is low, a voltage signal "g" (see FIG. 24g) the phase of which is synchronous with that of the AC signal "c" from the second AC signal source 19 and the crest value of which is determined in accordance with the liquid level in the liquid container. (It is to be noted that the phasic relation of the voltage signal "f" to the AC signal "c" changes by 180 degrees depending on whether the short circuit ring 208 is within the upper coil section 2041 of the auxiliary exciting coil 204 or the lower coil section 2042 of the same.
The voltage signal "f" from the low-pass filter 23 is treated by the first detection circuit 25 in accordance with the detection control signal "b" (see FIG. 24b) issued from the first detection control signal generating circuit 21. Thus, a voltage signal "h" having a wave form shown by FIG. 24h is outputted from the first detection circuit 25. The output signal "h" is fed to the first smoothing circuit 27 to be smoothed (see the lines "h'" in FIG. 24h). The DC voltage "h'" thus outputted from the smoothing circuit 27 has such a characteristic is shown by the curve "h'" of the graph in FIG. 23 due to the above-mentioned unique winding of the primary exciting coil 202. The value of the DC voltage "h'" is read by the first voltage detection circuit 29 and indicated in bar-graphic fashion by the primary indicator 321 of the double functioning indicator 32.
While, the voltage signal "g" from the high-pass filter 24 is treated by the second detection circuit 26 in accordance with the detection control signal "d" (see FIG. 24d) issued from the second detection control signal generating circuit 22. Thus, a voltage signal "i" having a wave form as shown by FIG. 24i is outputted from the second detection circuit 26. The output signal "i" is fed to the second smoothing circuit 28 to be smoothed (see the line "i'" in FIG. 24i). The DC voltage "i'" thus outputted from the smoothing circuit 28 has such a characteristic as shown by the curve "i'" of the graph in FIG. 23 due to the above-mentioned unique winding of the auxiliary exciting coil 204. The DC voltage "i'" is read by the second voltage detection circuit 30 and indicated in digital fashion by the secondary indicator 322 of the double functioning indicator 32.
Referring to FIG. 25, there is shown a circuit of a liquid level detecting device 10M of a thirteenth embodiment of the present invention. In this embodiment, unlike the case of the twelfth embodiment 10L, the upper and lower coil sections 2021 and 2022 of the primary exciting coil 202 are connected in parallel with each other, and the upper and lower coil sections 2041 and 2042 of the auxiliary exciting coil 204 are connected in parallel with each other, as shown in the drawing.
Referring to FIG. 26, there is shown a liquid level detecting device 10N of a fourteenth embodiment of the present invention. In this embodiment, a metal ring 208' constructed of for example aluminium or the like is used in place of the short circuit ring 208 of coil. The metal ring 208' consumes the magnetic energy on the principle of eddy-current loss. As the short ring 208, a ring constructed of magnetic powder-impregnated plastic is also usable in the invention.
If desired, the following modifications are also possible in the invention. One of them is a modification in which a suitable condenser is connected in series with the coil of the short circuit ring 208 to provide a resonance circuit in the same. With this, a current flowing in the circuit is increased thereby increasing the energy consumption of the short circuit ring 208. Accordingly, the output from the measuring coil 206 is increased.
Although in the above-mentioned embodiments 10A to 10N, the upper and lower coil sections 1221 and 1222 (or 2021 and 2022) of the primary exciting coil 122 (or 202) and those 2041 and 2042 of the auxiliary exciting coil 204 are each arranged to be symmetrical with respect to the middle portion therebetween, the primary and auxiliary exciting coils 122 (or 202) and 204 may each have an asymmetrical construction so long as the arrangement including afore-mentioned winding density inclination is employed.
Although, in the foregoing description, the coil bobbins are described to be constructed of iron or plastics, they may be constructed of other material. If desired, an air-cored arrangement may be used in the invention.
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Herein disclosed is a device for measuring a displacement of a movable member relative to a fixed member by putting the electromagnetic induction into practical use. The device comprises a first coil having first and second coil sections which are coaxially aligned along a common axis, a second coil arranged to establish a magnetic coupling with the first coil and extending along the common axis, and a short circuit ring arranged to establish a magnetic coupling with the first and second coils and movable relative to the same. The winding density of each of the first and second coil sections is gradually decreased from the outside end to the inside end thereof, and the winding density of the second coil is substantially even throughout the length of the same.
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FIELD OF THE INVENTION
The present invention relates to apparatus for covering open top vehicle containers, and, in particular, a hydraulically operated pivoting arm covering system having variable rate actuation.
BACKGROUND OF THE INVENTION
Governmental regulations require many open vehicle containers carrying particulate and waste cargos to limit spillage during transport. Various mechanical, electrical and hydraulic systems have been proposed for covering the load after filling, and uncovering the load at the discharge site. Hydraulic systems have become preferred for larger containers and vehicles carrying a variety of container sizes.
Typical hydraulic systems, as disclosed in U.S. Pat. Nos. 4,050,734 and 4,341,416 to Richard, and 4,981,317 to Acosta, employ a pair of pivoting arms that unroll a covering tarp over the container top in movement between an open and closed position. The arms are actuated by a hydraulic cylinders controlled by the operator at the side of the vehicle. For long bed containers or vehicles hauling containers of varying sizes, secondary sets of cylinder actuated extendable linkages are employed as shown representatively in U.S. Pat. Nos. 4,874,196 to Horvath; and Re. 36,135 and 6,237,985 to O'Brian.
The hydraulic tarp systems are generally controlled by hydraulic control systems located at the front side of the container behind the vehicle cab. Using two-way valve controls for single actuator sets, or joystick controls for multiple actuator sets, the operator furls or unfurls the cover while maintaining visual contact with its deployment. To minimize deployment time, faster covering rates are preferred by the drivers and the trucking organization. Such speed, however, comes at substantial maintenance costs. The rapid acceleration from the rest condition stresses the cover, the spooling mechanism, and the pivoting arms, and can cause damage to components and misalignments in the system. The impact and sudden deceleration at the end of the cylinder stroke pose similar problems. While slow cylinder rates have been used, the excessive time penalty involved has not been accepted, and accordingly time considerations have prevailed over maintenance preferences.
In view of the foregoing, it would-be desirable to provide a container covering system that would reduce maintenance costs while providing acceptable deployment cycles.
Accordingly it is an object of the present invention to provide a roll-up cover assembly for truck containers that reduces maintenance costs.
Another object of the invention is to provide a hydraulic actuator system for truck container covering apparatus that reduces component damage at the ends of the actuator stroke.
A further object of the invention is to provide a hydraulic actuator for a truck container covering system having reduced initial and terminal actuator rates for reducing equipment damage without significantly reducing overall deployment time.
Yet another object of the invention is to provide a variable rate covering system for open top containers providing controlled extension and retraction rates form open and closed positions.
SUMMARY OF THE INVENTION
The foregoing objects are accomplished by a hydraulic actuating system for a pivoting arm container covering system wherein the fluid flow rates to the hydraulic cylinders are reduced during the initial and final phases of the stroke to reduce acceleration and impact forces on the covering system components, and normal fluid flow rates are provided during the central phase, whereby the overall cycle time is not significantly affected. Therein, the hydraulic cylinders are provided with metering orifices that reduce fluid flow rates to and from the cylinder pressure chambers for predetermined portions of the stroke length, thereby cushioning the pivoting mechanism at the terminal positions.
DESCRIPTION OF THE DRAWINGS
The above and other objects and advantages of the present invention will become apparent upon reading the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a schematic drawing of a variable rate covering system in accordance with an embodiment of the invention;
FIG. 2 is a partial perspective view of a fixed arm covering system illustrating the cover in an intermediate position over an open top container;
FIG. 3 is a partial side view of the cover of FIG. 2 in the retracted position;
FIG. 4 is a view similar to FIG. 3 of the cover in the extended position;
FIG. 5 is a partial side view of an articulated arm cover system illustrating the cover in the retracted position;
FIG. 6 is a view similar to FIG. 5 illustrating the cover in an intermediate position;
FIG. 7 is a view similar to FIG. 5 illustrating the cover in the extended position;
FIG. 8 is a partially sectioned side view of a variable rate hydraulic cylinder for the cover systems;
FIG. 9 is an end view of the cylinder taken along line 9 — 9 of FIG. 8;
FIG. 10 is an end view of the cylinder taken along line 10 — 10 of FIG. 8;
FIG. 11 is a fragmentary partially sectioned cross sectional view of the hydraulic cylinder showing the piston in the retracted position;
FIG. 12 is a fragmentary partially sectioned cross sectional view of the hydraulic cylinder showing the piston in the extended position;
FIG. 13 is a fragmentary radial sectional view of the metering ring; and
FIG. 14 is a fragmentary axial sectional view taken along line 14 — 14 in FIG. 13 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings for the purpose of describing the preferred embodiment and not for limiting same, FIG. 1 schematically illustrates a variable rate covering system 10 for open top containers generally of the types shown in FIGS. 2 through 7. The system 10 includes a pair of variable rate hydraulic cylinders 12 a and 12 b attached at a base end 14 to brackets 16 carried on opposed sides of the container and attached at a head end 18 to base arms 20 , which pivot in response to cylinder extension and retraction to move a cover spool 22 between an unfurled open position 24 permitting loading and unloading of an open top container, and a furled closed position 26 enclosing the open top of the container to assist in retaining the container contents.
In the preferred embodiment, the cylinders 12 a and 12 b are connected in phased relationship from two-way valve 30 by fluid supply lines 32 , 34 , and 36 . Supply line 32 is connected from valve 30 to extension port 40 on cylinder 12 a . Supply line 34 is connected between retraction port 42 on cylinder 12 a and extension port 44 on the lower on cylinder 12 b . Supply line 36 is connected between retraction port 46 on cylinder 12 b and valve 30 . Fluid is supplied from reservoir 48 by a hydraulic pump 50 operated by motor 52 . A relief valve 54 routes fluid to the reservoir 48 under excessive pressure conditions. The cylinders 12 a and 12 b are maintained in phase relationship by rephase bypass circuits 56 . As described in greater detail below, the cylinders are provided with a piston assembly having a first metering rings on opposite ends and a central seal assembly.
In response to valve 30 actuation, the cylinders provide a variable rate stoke comprising a reduced rate for a distance d e between the left metering ring and the central seal assembly, a reduced rate for distance d r between the central seal assembly and the right metering ring, and operational rate for remaining stroke distance d c .
The system as above described may be incorporated into various covering systems, including without limitation a fixed arm system of the type shown in FIGS. 2 through 4, or the articulated arm system shown in FIGS. 5 through 7. The system may also be used in covering systems employing other supplemental linkages, such as telescoping outer arms. The cylinders as described above have primary reference to use in conjunction with the lower base arms in such systems and will be hereinafter described with reference thereto.
Referring to FIGS. 2 through 4, a fixed arm covering system 110 is used to deploy a cover 112 over an open top container 114 . The cover 112 is mounted on a roll up spool 116 attached at the outer ends of pivoting arms 118 for movement between a retracted position shown in FIG. 3 wherein the cover 112 is furled, through an intermediate position shown in FIG. 2, to an extended position wherein the cover is unfurled and encloses the top end of the container 114 . Movement of the arms 118 is effected by hydraulic cylinders 120 , in accordance with the invention, and operator controlled by lever valve assembly 122 disposed at the front driver side of the container. During movement to and from the retracted position of FIG. 3, the cylinders operate at a reduced rate. During movement to and from the extended position of FIG. 4, the cylinders also operate at a reduced rate. During the intermediate stage shown in FIG. 2, the cylinders operate at a normal rate dependent on conventional operating conditions.
For the articulated cover system 200 shown in FIGS. 5 through 7, an arm assembly 202 is pivoted by base cylinders 204 to move a cover 205 over the open upper end of a vehicle mounted container 206 . The arm assembly 202 includes a base arm 210 operated by variable rate hydraulic cylinder 204 in accordance with the invention. An upper secondary arm 214 is attached at the upper end of base arm 210 and operated by secondary hydraulic cylinder 216 . Depending on preference, a multiple rate stroke may be provided by the cylinders 216 . The cover system 200 is moved by cojoint actuation from the cylinders 204 and 216 from the retracted position shown in FIG. 5 at a reduced rate, cojointly by cylinders 204 and 216 during an intermediate distance shown in FIG. 6, and to the extended position shown in FIG. 7 enclosing the top of the container.
Referring to FIGS. 8 through 10, the cylinder 12 a , by way of example, for the system described above comprises tube assembly 400 including a cylinder tube 402 carrying a sealed tail 404 having an end ring 406 for mounting on the vehicle at appropriate brackets. A piston assembly 410 including a piston rod 412 is slidably carried in the bore of the tube 402 . The piston rod 412 outwardly terminates with an apertured ring 414 for connection to the pivoting arm of the applicable cover system. The piston rod 412 of the tube assembly 400 is conventionally sealed by packing gland lot 416 . The piston assembly 410 includes a tail metering section 420 , a head metering section 422 , and a center sealing section 424 , axially separated by annular spacer sleeves 426 , 428 , all of which are carried by the end portion of the piston rod 412 and operatively connected therewith by threaded fastener 429 . Radially extending extension fluid port 430 and retraction fluid port 432 are positioned along the tube 402 . A radially extending rephase port assembly 434 is positioned on the tube 402 intermediate the ports 430 and 432 . The piston sections 420 , 422 , and 424 have a sliding fit with the inner bore of the tube 402 . The tail metering section 420 includes a circumferential groove carrying a metering ring 440 . The head metering section 422 includes a circumferential groove carrying a metering ring 442 .
Referring to FIGS. 11 and 12, the center sealing section 424 includes a zero leakage sealing assembly including an axially spaced series of circumferential grooves carrying a pair of axially spaced, zero leakage bearing rings 444 , 446 and an intermediate low friction sealing ring 448 . The spacer sleeves 426 and 428 have a reduced diameter establishing annular fluid chambers between the adjacent piston sections. The spacer sleeves have a length for establishing the requisite distance between the adjacent fluid port and the adjacent metering rings for establishing the lengths of the reduced flow rate distances, d e and d r as shown in FIG. 1 . The extension fluid port 430 includes a radial passage partially obstructed by the bearing ring 444 in the retracted position. The retraction fluid port 432 includes a radial passage partially obstructed by the bearing ring 446 in the extended position as shown in FIG. 12 .
Referring to FIGS. 13 and 14, the metering ring 440 and metering ring 442 are provided with radial slots 460 in the axial end faces and are retained in outwardly opening circumferential grooves 462 . The metering rings have a larger diameter than the base of the groove 462 thereby establishing a flow path between opposed slots. By controlling number, width and depth of the slots, a controlled leakage is established past the metering rings in fluid path between the port and the respective pressure chamber. In a well know manner, the rephase port assembly vents on either side of the seal assembly to allow both pistons to reach a terminal aligned position at the end of each retraction cycle thereby maintaining synchronous aligned movement of the pivoting arms and even deployment of the container cover.
In operation, at the commencement of an extension cycle as conditioned by the two-way control valve 30 , the line 32 is pressurized. Initially the flow rate through the extension port is throttled by the bearing ring 444 to limit in a first instance the extension rate. After the extension port is fully open, the flow pressurizes the annular chambers between the piston sections. Flow to the extension pressure chamber is restricted by the metering ring 440 thereby in a second instance providing a second extension rate, which continues until the metering ring passes beyond the extension fluid port 430 . Thereafter, non-restricted flow is applied to the extension pressure chamber effecting a fill extension rate based on system conditions for a center part of the piston stroke. During the center extension stroke, non-restricted fluid flow exits through retraction fluid port 432 . When the head metering section is adjacent the retraction port, the metering ring 442 begins to throttle the exiting fluid flow, thus reducing the extension rate and slowing the pivoting of the arms. As the piston approaches the fully extended position, the retraction port is partially obstructed by the bearing ring 446 , further restricting the exit flow and consequently the terminal extension rate. At the end of the strokes, over pressure conditions resulting from continued valve opening are regulated by the relief valve, 54 , (FIG. 1 ).
For the retraction stroke, the reverse conditions apply. The metering ring 442 throttles extension to provide a reduced retraction rate until the metering rings pass the retraction port 432 , at which time a full retraction rate is provided, until the rear metering ring 440 passes the extension fluid port 430 , restricting the exit flow and reducing the retraction rate until the piston is seated at the end of the stroke.
Accordingly, it will be appreciated that variable rate cylinders provide reduced acceleration and deceleration conditions at the ends of the piston stroke to lessen loading and impact forces on the cover components at the terminal moments in the open and closed conditions, thereby reducing maintenance cost and extending the operating life of the system. Because of the cushioning features that allow safe seating and removal from the stop positions, a higher flow rate can be used during the center movement thereby increasing the pivoting speed of the arm assemblies and offsetting any increased times occasioned by the slower end rates. Further, the length of the space sleeves may be adjusted to provide ample slow rate motion to allow the operator to safely guide the cover to the stop positions. In many configurations, alignment at the front end of the container is more difficult, particularly in articulated arm designs where various truck and container surfaces must be avoided. Accordingly, it may be preferable to provide an increased slow rate zone during this portion of the traverse. At the rear end of the container, the stowing is more straightforward and a lesser cushioning zone may be sufficient.
Having thus described a presently preferred embodiment of the present invention, it will now be appreciated that the objects of the invention have been fully achieved, and it will be understood by those skilled in the art that many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the sprit and scope of the present invention. The disclosures and description herein are intended to be illustrative and are not in any sense limiting of the invention, which is defined solely in accordance with the following claims.
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A variable rate covering system for open top vehicle containers includes a hydraulic actuating system for pivoting arms carrying a roll up cover wherein the fluid flow rates to the hydraulic cylinders are reduced during the initial and final phases of the stroke to reduce acceleration and impact forces on the arms, cover and components, and normal fluid flow rates are provided during central phase movement without significantly affecting overall cycle time. The hydraulic cylinders are provided with metering orifices that reduce fluid flow rates to and from the cylinder pressure chambers for predetermined portions of the stroke length, thereby cushioning the pivoting mechanism at the terminal positions.
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TECHNICAL FIELD
This application claims the benefit under 35 U.S.C. §119 of U.S. patent application No. 60/570,817 filed on 14 May 2004 and entitled DIELECTRIC WELDING METHODS AND APPARATUS.
TECHNICAL FIELD
The invention relates to methods and apparatus for welding dielectric materials such as plastics. Some embodiments of the invention relate to welding using electromagnetic signals (e.g. radiofrequency signals). The invention may be applied to welding plastic membranes together in the presence of metals or other exposed electrically conductive materials (hereinafter referred to as ECM). The invention has broad application for manufacturing products which include welded plastic membranes that have ECM near to the weld locations.
BACKGROUND
Dielectric welding, also known as capacitance, radio-frequency, or high frequency welding, provides a way to fuse materials together. The resulting weld can be as strong as the original workpiece materials. Dielectric welding is commonly used for joining various plastic materials together.
In dielectric welding, an alternating electrical field (typically alternating at a high frequency) is applied across an area to be welded. This is typically done by applying a signal between electrodes. The signal creates a varying, high-frequency electromagnetic field. When a material which is a poor electrical conductor is exposed to such a field, heat is generated in the material. The heat results from electrical losses that occur in the material. The heat deposited in the material causes the temperature of the material to rise. The heated materials become fused together.
Dielectric welding relies on certain properties of the material in the parts being welded, for example, the geometry and dipole moments of molecules of the material, to cause the generation of heat in a rapidly alternating electromagnetic field. Not all materials can be dielectric welded. Polyvinyl chloride (PVC) is commonly welded by dielectric welding. Other thermoplastics that can be dielectric welded are EVA and polyurethanes.
A typical dielectric welding apparatus places materials to be joined between two electrodes, which are typically metal plates or bars. The electrodes are connected to an oscillator. The oscillator is turned on to heat the materials, which fuse together when they have been heated sufficiently. The electrodes may hold the materials together during heating and cooling.
There are situations where it is desirable to make products which have ECM, e.g. metal components, embedded in or attached to one or more membranes or other parts of a dielectric material which are to be welded together. A problem is that ECM in the vicinity of the electrodes of a dielectric welder can cause electrical discharges in the form of arcs or sparks. Such electrical discharges can damage the product being made, the welding apparatus and/or the dielectric welder itself. Electrical arcing can be dangerous to machines and humans.
It is not always possible or convenient to add ECM after welding has been completed. There is a need for methods and apparatus which may be used to perform dielectric welding in the vicinity of ECM.
SUMMARY OF THE INVENTION
The invention relates to methods and apparatus for welding plastic materials membranes together in the vicinity of electrically conductive materials.
Various aspects of the invention and features of specific embodiments of the invention are described below.
BRIEF DESCRIPTION OF THE DRAWINGS
In drawings which illustrate non-limiting embodiments of the invention,
FIG. 1 is a schematic view of a dielectric welding apparatus;
FIG. 2 is an isometric view showing first and second electrode assemblies;
FIG. 3 is a perspective view of one of the electrode assemblies of FIG. 2 ;
FIG. 4 is a plan view of one of the electrode assemblies of FIG. 2 ;
FIG. 4A is a cross sectional view (in the plane A—A of FIG. 4 ) of the electrode assembly of FIG. 4 ;
FIG. 4B is an exploded view of the electrode assembly of FIG. 4 ;
FIG. 5 is a plan view of the other one of the electrode assemblies of FIG. 2 ;
FIG. 6 is an isometric view of a buffer member; FIG. 6A is a top plan view thereof; FIG. 6B is a section in the plane A—A thereof; and FIG. 6C is a section in the plane B—B thereof;
FIG. 7 is an isometric view of a part of an electrode assembly; FIG. 7A is a top plan view thereof; FIG. 7B is a section in the plane C—C thereof; and FIG. 7C is a section in the plane D—D thereof;
FIG. 8 is an isometric view the electrode assembly of FIG. 7 holding a product to be welded with a top membrane removed for clarity; FIG. 8A is a top plan view thereof; FIG. 8B is a section in the plane E—E thereof; and FIG. 8C is a section in the plane F—F thereof;
FIG. 9 is an isometric view the electrode assembly of FIG. 8 with the top membrane of the product in place to be welded; FIG. 9A is a top plan view thereof; FIG. 9B is a section in the plane G—G thereof; and FIG. 9C is a section in the plane H—H thereof;
FIG. 10 is an isometric view the electrode assembly of FIG. 9 showing electrodes, but not a buffer portion, of a top electrode assembly; FIG. 10A is a top plan view thereof; FIG. 10B is a section in the plane I—I thereof; and FIG. 10C is a section in the plane J—J thereof;
FIG. 11 is an isometric view the electrode assembly of FIG. 10 showing the buffer portion of the top electrode assembly; FIG. 11A is a top plan view thereof; FIG. 11B is a section in the plane K—K thereof; and FIG. 11C is a section in the plane L—L thereof;
FIG. 12 is an isometric view of the top electrode assembly portion shown in FIG. 11 ; FIG. 12A is a top plan view thereof; FIG. 12B is a section in the plane M—M thereof; and FIG. 12C is a section in the plane N—N thereof; and,
FIG. 13 is an isometric view of the top electrode assembly portion shown in FIG. 11 supporting a top membrane of a product; FIG. 13A is a top plan view thereof; FIG. 13B is a section in the plane O—O thereof; and FIG. 13C is a section in the plane P—P thereof.
DESCRIPTION
Throughout the following description, specific details are set forth in order to provide a more thorough understanding of the invention. However, the invention may be practiced without these particulars. In other instances, well known elements have not been shown or described in detail to avoid unnecessarily obscuring the invention. Accordingly, the specification and drawings are to be regarded in an illustrative, rather than a restrictive, sense.
Consider the case where one wishes to create a pattern of welds joining a pair of membranes. The membranes are made of a plastic material which is suitable for dielectric welding. However, one or both of the membranes has attached to it, or embedded in it, one or more electrically conductive elements (ECM). The ECM may, for example, be metal parts. The ECM may be exposed. If the one or more ECM is near to a location in which it is desired to weld the membranes together then the presence of the one or more ECM may interfere with dielectric welding of the membranes together using conventional methods.
Welding methods and apparatus can interpose an electrically insulating barrier between ECM in a product being fabricated and the electrodes of a dielectric welder. Provision of an electrically insulating barrier supports welding non-conductive membranes in close proximity to ECMs.
Electrode structures for dielectric welding may have integrated insulating barriers located so that the insulating barriers will be interposed between electrodes of the electrode structures and the ECMs when the electrodes are in position to make a weld. In some embodiments, the electrode structures include one or more electrodes arranged in a pattern corresponding to a desired weld pattern.
The electrodes may be made of any suitable electrically conducting materials. Aluminum, brass, and copper are examples of materials from which electrodes may be fabricated. The electrodes may be fabricated using any suitable process. For example, the electrodes may be machined, assembled from component parts, cast, etc.
Buffers are located between the electrodes. The buffers are made of electrically insulating materials. The buffers are hollowed out to receive projecting portions of one or more ECMs. In some embodiments the buffers fill the spaces between the electrodes.
The buffers may be made from any of a wide variety of suitable materials. Examples of materials suitable for use as buffers include: electrically non-conductive ceramic materials, polytetrafluoroethylene, polyurethane, polypropylene, polyethylene, silicone, and combinations of these materials. The buffers may be made using any suitable manufacturing processes. For example, the buffers may be machined or otherwise formed from solid materials or cast. A castable polyurethane or silicone may be used to cast all or part of the buffers. The buffers may be partially cast and partially made from solid materials. In preferred embodiments, the buffers have dielectric strengths at least 2 times greater than a dielectric strength of air in a range of frequencies of a high frequency welding current to be used.
FIG. 1 shows schematically a dielectric welding apparatus 10 according to one embodiment of the invention. Apparatus 10 includes first and second electrode assemblies 12 A and 12 B. Electrode assemblies 12 A and 12 B are disposed on either side of a product 14 comprising plastic materials, typically membranes 16 , to be welded together and one or more ECMs 18 . First and second electrode assemblies 12 A and 12 B each have a face 13 facing toward the other electrode assembly.
Apparatus 10 comprises a frame 11 . First electrode assembly 12 A is supported by frame 11 and is movable toward and away from second electrode assembly 12 B to permit product 14 to be compressed between electrode assemblies 12 A and 12 B. In some embodiments, electrode assemblies 12 A and 12 B can be pressed together with a desired force by a mechanical linkage mechanism, a pneumatic or hydraulic mechanism, an electrically controlled actuator or some other suitable pressing means. Electrode assemblies 12 A and 12 B may be supported by any suitable mechanisms which maintain registration between electrode assemblies 12 A and 12 B.
In the illustrated embodiment, frame 11 may be the frame of a conventional dielectric welding machine, for example. First electrode assembly 12 A is mounted to a first platen 19 A. Second electrode assembly 12 B is mounted to a second platen 19 B. Either or both of the platens are movable to achieve placement of products to be welded and removal of welded products. Apparatus 10 supports the compression, welding, and cool down phases of dielectric welding. As the basic operation and constructions of dielectric welding machines are understood by those skilled in the art, features known from conventional dielectric welding apparatus are not described in detail herein.
First and second electrode assemblies are each connected to a dielectric welding power supply 20 . In the illustrated embodiment, the first and second electrode assemblies are in electrical contact with power supply 20 by way of electrical contact between their bases (or non-welding sides) and the corresponding platens 19 A, 19 B. Except as indicated herein, apparatus 10 may be constructed and operated in substantially the same manner as an existing dielectric welding machine. In operation:
product 14 is compressed between first and second electrode assemblies 12 A and 12 B; power supply 20 is operated to supply high frequency dielectric welding current to first and second electrode assemblies 12 A and 12 B; and, after sheets 16 have had an opportunity to fuse together at the weld locations, the high frequency current is discontinued and, optionally after a cooling interval, first and second electrode assemblies are separated to allow the welded product 14 to be removed.
FIG. 2 is an isometric view showing first and second electrode assemblies 12 A and 12 B according to an example embodiment of the invention. Each electrode assembly 12 A and 12 B has one or more electrodes 30 . Electrodes 30 of first electrode assembly 12 A are arranged as a mirror image of electrodes 30 of second electrode assembly 12 B. When first and second electrode assemblies 12 A and 12 B are brought together face-to-face the electrodes 30 of electrode assemblies 12 A and 12 B follow one another. Electrodes 30 of first and second electrode assemblies 12 A and 12 B are directly opposed to one another on either side of product 14 . The pattern of electrodes 30 defines the pattern of locations at which membranes 16 will be welded together.
In the illustrated embodiment, electrodes 30 include a peripheral electrode 30 A which welds a peripheral seam on product 14 , internal electrodes 30 B which define a pattern of welds in the interiors of products 14 , and electrodes 30 C which make spot welds on product 14 . In the illustrated embodiment, electrodes 30 A and 30 B are linear electrodes and electrodes 30 C are isolated spots. All of the electrodes are electrically connected to an electrically conducting base 33 . When first and second electrode assemblies 12 A or 12 B are mounted to corresponding platens 19 A and 19 B, bases 33 are in electrical contact with the platens and thereby establish electrical contact between the welding power source 20 , which is connected to the platens, and electrodes 30 .
The spaces between electrodes 30 are filled with buffer areas 32 . In the illustrated embodiment, buffer areas 32 are composed of a cast material 32 cast between electrodes 30 .
Buffer areas 32 have recesses 34 to receive the projecting parts of ECMs 18 . Recesses 34 may be shaped to substantially conform with the shapes of the projecting parts of ECMs 18 . Different ones of recesses 34 may have different shapes and configurations.
As shown best in FIG. 4A , buffers 32 fill the space between electrodes 30 . Buffers 32 are flush with the tops of electrodes 30 . Buffers 32 provide barriers 33 of electrically insulating material between recesses 34 and electrodes 30 .
When first and second electrode assemblies are brought together on either side of product 14 , the embedded and projecting ECMs 18 are seated in features 34 . This insulates ECMs 18 from electrodes 30 . Features 34 can also support, locate, and align ECMs 18 in relation to one another and the membranes 16 to be welded.
Buffer areas 32 may optionally contain features to pre-form, locate and pre-align membranes 16 to be welded. Such features may include electrical-mechanical devices and or intermittent differential air pressures or vacuums.
Buffer areas 32 may contain features to assist the ejection and removal of welded membranes with embedded ECM from the major components of the device. Such features could be implemented, for example, by providing electrical-mechanical devices and or intermittent differential air pressures or vacuums.
FIGS. 6 through 13C are more detailed views of portions of example first and second electrode assemblies which cooperate to make a weld.
FIG. 6 shows a section of buffer material 32 which extends between a pair of electrodes 30 in an electrode assembly 12 B as shown in FIG. 7 . FIG. 7 shows only a part of electrode assembly 12 B. Electrode assembly 12 B cooperates with another electrode assembly 12 A as shown in FIG. 11 . When electrode assemblies 12 A and 12 B are brought together on either side of a product 14 , electrodes 30 of electrode assembly 12 A overlie and are aligned with electrodes 30 of electrode assembly 12 B.
As shown in FIGS. 8 through 11C , an ECM 18 is received in recess 34 of electrode assembly 12 B. ECM 18 is attached to a first membrane 16 B of a weldable plastic material. Recess 34 is shaped to generally correspond to the shape of the end of ECM 18 which projects from membrane 16 B on the side toward electrode assembly 12 B.
As shown in FIGS. 9 through 11C , a second membrane 16 A of product 14 is curved away from membrane 16 B to provide a tubular passage 37 in product 14 . The buffer 32 of first electrode assembly 12 A is cut away to form a groove 38 which accommodates and shapes second membrane 16 A. Vacuum ports (not shown) may be provided in buffer 32 of second electrode assembly 12 A to pull second membrane 16 A into and against the contours of groove 38 prior to welding. After welding, the end of ECM 18 which is closest to first electrode assembly 12 A is located within passage 37 .
Applying a high frequency alternating welding current between electrodes 30 of first electrode assembly 12 A and second electrode assembly 12 B causes membranes 16 B and 16 A to become fused together at locations 17 ( FIG. 11B ).
Where a component (e.g. a member, part, assembly, device, circuit, etc.) is referred to above, unless otherwise indicated, reference to that component (including a reference to a “means”) should be interpreted as including as equivalents of that component any component which performs the function of the described component (i.e., that is functionally equivalent), including components which are not structurally equivalent to the disclosed structure which performs the function in the illustrated exemplary embodiments of the invention.
As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof. For example:
Buffers 32 are not necessarily present in areas away from ECMs. Buffers 32 are present in only one of first and second electrode assemblies in some embodiments of the invention. The widths of electrodes 30 may be varied. Electrodes 30 may be arranged to form any suitable pattern. A welding power supply may be connected directly to electrodes 30 or bases 33 instead of indirectly by way of platens 19 A and 19 B, as illustrated.
While a number of example aspects and embodiments have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions and sub-combinations as are within their true scope.
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Dielectric welding apparatus has opposed electrodes that can be engaged on either side of a product to be welded and a dielectric welding power supply that supplies welding potentials to the electrodes. The apparatus includes electrically insulating buffer material adjacent to at least one of the electrodes. A recess formed in a surface of the buffer material receives an end of an electrically-conductive member in the product. The buffer material prevents arcing between the electrodes and the electrically-conductive member.
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This application is a continuation of U.S. application Ser. No. 527,469, filed Aug. 29, 1983, filed as PCT EP82/00277, Dec. 29, 1982, published as WO83/02252, July 7, 1983, now abandoned.
FIELD OF THE INVENTION
The invention relates to a process and an apparatus for the manufacture of a single-ply or multi-ply valved sack, of paper or film, having a self-sealing valve.
BACKGROUND OF THE INVENTION
Valved paper sacks are used extensively for packaging pulverulent or granular material. The scatterable or pourable material can be introduced on automatic filling equipment, and the valve, which self-seals, after filling, through the pressure exerted by the contents, in most cases makes an additional process step for sealing the filled sack unnecessary; alternatively, additionally applied sealing sheets are subjected to substantially less stress because of the self-sealing properties of the valve.
In addition to the extensively employed stitched valved sack, the block-bottom valved sack is very important. Whilst the stitched sack on the one hand has the advantage that it is inexpensive to manufacture, it also reveals the disadvantage of not being absolutely tight. On the other hand, a block-bottom valved sack exhibits good tightness but against this is more expensive, and requires more material, in its manufacture.
European Patent Application No. 82/108,232.8 has proposed a gusseted valved sack in which the valve is introduced into the lengthwise weld of the piece of tubing, in the vicinity of one of the two folded bottoms of the sack. This gusseted valved sack is less expensive to manufacture than a block-bottom valved sack; moreover, it is even superior to the latter in tightness.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide, as far as possible using conventional sack machinery, a process and an apparatus with which such proposed gusseted valved sacks with a valve inserted into the lengthwise weld of the sack tubing can be manufactured inexpensively.
The process according to the invention, and the apparatus employing this process, are distinguished in that at the end of a transporting device for an open web of the sack material, shortly before the latter is led into a tube-forming zone, a valve-manufacturing unit is located, preferably above the material web path, in which unit valves are produced from a stock reel of paper and fed in a positioned manner to the open sack web, which has been pre-glued in defined zones. The prefabricated paper valves are brought into contact with the pre-glued open sack web and after the valve has been applied the sack web carrying the valve passes through a pressure zone in which secure gluing of the valve sleeve supplied is achieved.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention and the advantageous details are explained further below in relation to an example, with reference to the drawings. In the drawings:
FIG. 1 shows a schematic representation of a transport device for a sack web with a device, arranged above it, for the manufacture of a valve sleeve;
FIGS. 2 to 6 represent the principle of partzones of the device for the manufacture of the valve sleeve and
FIG. 7 serves to illustrate the individual process steps in the manufacture of a valve sleeve.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a portion of a sketch illustrating the principle of a sack machine to which a valve-manufacturing unit has been added. A sack web 1, which in the case of a single-ply sack can be described as an open sack web, whilst in the case of a multi-ply sack it represents the inner sack web, is first guided over a roll 4 and pre-glued in a gluing station B in the area where the valve is subsequently applied. The gluing station B consists essentially of a glue trough 5, a pick-up roll 6 and an applicator roll 7 adapted to apply the glue in the appropriate format. A guide roll 3 again changes the direction of the open sack web 1. A valve or valve sleeve 24 is applied by means of the roller 13b of a valve-manufacturing apparatus, to be described in more detail below, and on passage through a pair of pressure rollers, 18, the sack web and the valve sleeve applied to it are pressed together to ensure intimate gluing. The open sack web accordingly carries the applied valve when reaching a guide roll 2 at the exit point of the intermediate product or at the transfer to a sack-manufacturing machine.
To assist pressing the components together, a conveyor belt 17 circulates in the area of a pressure station 13, and a cylinder 13b, which at the same time applies the valve sleeve 24 to the open sack web 1, serves, on the side away from a cylinder 13a, as a guide roll for one or more conveyor belts 17.
The valve former and applicator to be described below comprises the following sub-units:
A roll 22 represents the material stock roll for a valve web 8, from which the valve sleeves 24 are produced in a manner described in more detail below. 21 indicates a traction unit which ensures that the valve web 8 is transported in the required format. In a cross-cutter 9 with cutting blade 14, mounted on an upper roll 9a, with a lower roll 9b serving as counter-pressure roll, downstream of point C, portions in the length required for the manufacture of the valves are severed from the valve web 8. A traction group 21' serves to ensure the further transport of the successively produced valve sheets 24', and the groups of rolls 10, 11, 12 successively produce a first creasing, a zonal gluing, a second creasing and a folding-over of the valve sheets 24' to form a valve 24 in the form of the numeral "9", and finally, the transfer of the finished valve sleeve 24 to the transfer cylinder 13b already mentioned.
FIGS. 2, 3, 4 and 5 show in detail the creasing and gluing processes which occur in the zone of the stations 10 to 12:
FIG. 2 first of all illustrates the process step on an individualized valve sheet 24', when the latter reaches to creasing assembly 10. The lower creasing cylinder 10b carries two creasing flaps 16a and 16b, which are controlled by cams 15a, 15b. FIG. 2 shows furthermore that the individualized valve sheet 24' has been seized by the front creasing flap 16a of the creasing cylinder 10b just behind the leading paper edge, so that a front tab 24a of the valve sheet 24' has been bent up.
FIG. 3 shows the next step: the creasing flap 16a continues to hold the valve sheet 24' with the front tab 24a firmly, and the open valve sheet 24' is glued zonally by the glue applicator roll 11c of the gluing station 11, so that, as FIG. 4 shows, the glue trace 23 is applied to the open valve sheet 24'. In FIGS. 3 and 4, the gluing unit 11 is simply represented by the glue applicator roll 11c. However, FIG. 1 shows that the gluing unit 11 additionally has a gluing trough 11a and a pick-up roll 11b.
FIG. 4 shows that as the creasing cylinder 10b continues to rotate, the creasing flap 16a has now also opened whilst the creasing flap 16b has now seized the as yet open valve sheet 24' resulting, because of the intrinsic stiffness of the paper, in a tab 24b being turned up, which tab in turn carries, angled in the opposite direction, the backward-pointing tab 24a. When the as yet open valve sheet 24' passes through the roll nip 31 between the creasing cylinder 10b and a gripper drum 12, the advancing tab 24b is now folded over completely, so that the tab 24a comes to rest on the glue trace 23. This completes the folding of the valve which, though it is still lying flat, is in principle already in the shape of a numeral 9.
The gripper drum 12 now seizes, by means of the gripper 25, the valve sheet 24' on the creasing drum 10b and finally, at the contact point of the rolls 12 and 13b, the finished valve sleeve 24 is transferred from the gripper drum 12 to the transfer cylinder 13b, as shown in FIG. 6. To effect this transfer, a gripper finger 25 (not shown in more detail) must open at this transfer point; at the same time the valve sleeve 24, lying flat, is lightly seized by a fine needle 20 attached to the transfer cylinder 13b and the actual transfer of the finished folded valve sleeve 24 to the transfer cylinder 13b is ensured by a suction pad 19 connected to an intermittently acting vacuum pump, not shown in more detail. At the lower point of the transfer cylinder 13b the vacuum of the suction pad 19 is switched off so that, assisted by the belt or belts 17, the transfer of the valve sleeve 24 from the transfer cylinder 13b onto the previously described sack web, preglued zonally by the gluing unit 5, 6, 7, may take place.
Preferably, the upper creasing cylinder 10a has two creasing blades, not shown in more detail, which, when the open valve sheet 8 passes through the roll nip 30 between the two creasing cylinders 10a and 10b, ensure that the valve sheet 8 is seized by the two creasing flaps 16a and 16b in the lower creasing cylinder 10b. For this, a cycle control system must be provided so that the creasing flaps 16a and 16b each are open before passing into the roll nip 30 between the creasing cylinders 10a and 10b, so that the creasing blades of the upper creasing cylinder 10a can lightly enter the gaps created by the open creasing flaps 16a, 16b and thereby press the paper into these open creasing flaps. In this way the open valve sheet 8, after passing through the nip 30 between the upper creasing cylinder 10a and the lower creasing cylinder 10b, is already seized by both the creasing pincers even before the open valve sheet 8 passes the gluing station 11. However, with such a creasing flap control system it may happen that after the creasing flap 16a has opened the larger tab 24b will not adequately stand up, which however would be advantageous for complete folding-over of the tab 24b at the point of passage 31 between the cylinders 10b and 12. Advantageously, therefore, the valve-manufacturing unit can also be equipped with two creasing blade cylinders so that the creasing cylinder 10a has only one creasing blade, with which secure gripping of the valve sheet 8 by the creasing flap 16a can be ensured. The severed valve sheet 24', which in this way is only gripped at one place by one creasing pincer then passes through the gluing station 11 before a second creasing cylinder, not shown in more detail, ensures the gripping of the valve sheet 24' by the creasing pincer 16b. For secure turning-up of the valve tab 24b it is then advantageous to open the front creasing flap 16a already during, or immediately after, the gripping of the valve sheet 24' by the creasing flap 16b. The nip 31 between the two cylinders 10b and 12 serves both to fold over the tab 24b and to ensure gripping of the valve, finished by this folding-over, by means of the gripper finger 25, which can also be constructed as a gripping pincer.
Finally, FIG. 7 once again explains, through perspective separate illustrations, the individual process steps in the manufacture of the 9-shaped valve. FIG. 7a shows the as yet uncreased valve sheet 24', after already having been severed from the valve web 8, ie. the sheet in the form in which it passes, for example, the zone of the traction station 21'. FIG. 7b illustrates the valve sheet 24' after the first creasing in the creasing flap 16a of the creasing cylinder 10b, resulting in formation of the front tab 24a. FIG. 7c shows the valve sheet 24', pre creased once, with a front flap 24a, after passing through the gluing station 11 which applies the glue trace 23. FIG. 7d finally shows the valve sheet 24' after the second creasing in the creasing flap 16b, so that the valve sheet 24' having a large tab 24b and a small tab 24a is clearly discernible. Finally, the valve 24, shown finished in FIG. 7e, is applied on the sack web 1, provided with the glue traces 26, shown in FIG. 7f, and FIG. 7g further shows the open sack web 1 with the valve 24 applied to it, in the manner in which the combination of sack web 1 and valve 24 appears after passing through the pair of pressure rollers 18.
In order to permit simple adaptation of the valve manufacturing process to different sack sizes, a cycle control system can be provided for the valve manufacturing unit so that, for example, the onward transport of the severed valve sheets 24' by the traction group 21' is synchronized with the variable sack size.
The process according to the invention for the manufacture of paper or film sacks with a self-sealing valve, and the apparatus according to the invention, suitable for this process, are in particular distinguished by the fact that, employing a substantially fully automatic process, inexpensive self-sealing valved sacks for pulverulent or granular material can be manfactured and different sack sizes can be taken into account.
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Process and apparatus for the manufacture of a valved sack with a self-sealing valve in which at the end of a transporting device for an open web of the sack material, shortly before the sack material is fed into a tube-forming zone, a valve-manufacturing unit is located, preferably above the material web path, in which unit valves are produced from a stock reel of paper and fed in a positioned manner to the open sack web, which has been pre-glued into fine zones. The pre-fabricated paper valves are then brought in contact with the pre-glued open sack web and the valve sleeve is securely glued into the sack in a gluing zone within the apparatus.
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FIELD OF THE INVENTION
The present invention relates generally to navigational receivers, and more particularly to systems and methods that enable standalone navigation receivers to determine their position without the immediate need of broadcast ephemeris.
BACKGROUND OF THE INVENTION
With the development of radio and space technologies, several satellite-based navigation systems have already been built and more will be in use in the near future. One example of such satellite-based navigation systems is the Global Positioning System (GPS), which is built and operated by the United States Department of Defense. The system uses twenty-four or more satellites orbiting the earth at an altitude of about 11,000 miles with a period of about twelve hours. These satellites are placed in six different orbits such that at any time a minimum of six satellites are visible at any location on the surface of the earth except in the polar region. Each satellite transmits a time and position signal referenced to an atomic clock. A typical GPS receiver locks onto this signal and extracts the data contained in it. Using signals from a sufficient number of satellites, a GPS receiver can calculate its position, velocity, altitude, and time.
A GPS receiver has to acquire and lock onto at least four satellite signals in order to derive the position and time. Usually, a GPS receiver has many parallel channels with each channel receiving signals from one visible GPS satellite. The acquisition of the satellite signals involves a two-dimensional search of carrier frequency and the pseudo-random number (PRN) code phase. Each satellite transmits signals using a unique 1023-chip long PRN code, which repeats every millisecond. The receiver locally generates a replica carrier to wipe off residue carrier frequency and a replica PRN code sequence to correlate with the digitized received satellite signal sequence. During the acquisition stage, the code phase search step is a half-chip for most navigational satellite signal receivers. Thus the full search range of code phase includes 2046 candidate code phases spaced by a half-chip interval. The carrier frequency search range depends upon the Doppler frequency due to relative motion between the satellite and the receiver. Additional frequency variation may result from local oscillator instability.
Coherent integration and noncoherent integration are two commonly used integration methods to acquire GPS signals. Coherent integration provides better signal gain at the cost of larger computational load, for equal integration times.
The signals from the navigational satellites are modulated with navigational data at 50 bits/second. This data consists of ephemeris, almanac, time information, clock and other correction coefficients. This data stream is formatted as sub-frames, frames and super-frames. A sub-frame consists of 300 bits of data and is transmitted for 6 seconds. In this sub-frame a group of 30 bits forms a word with the last six bits being the parity check bits. As a result, a sub-frame consists of 10 words. A frame of data consists of five sub-frames transmitted over 30 seconds. A super-frame consists of 25 frames sequentially transmitted over 12.5 minutes.
The first word of a sub-frame is always the same and is known as TLM word and first eight bits of this TLM word are preamble bits used for frame synchronization. A Barker sequence is used as the preamble because of its excellent correlation properties. The other bits of this first word are telemetry bits and are not used in the position computation. The second word of any frame is the HOW (Hand Over Word) word and consists of the TOW (Time Of Week), sub-frame ID, synchronization flag and parity with the last two bits of parity always being ‘0’s. These two ‘0’ s help in identifying the correct polarity of the navigation data bits. The words 3 to 10 of the first sub-frame contains clock correction coefficients and satellite quality indicators. The 3 to 10 words of the sub-frames 2 and 3 contain ephemeris. The ephemeris is used to precisely determine the position of the GPS satellites. The ephemeris is uploaded every two hours and are valid for four hours to six hours. The 3 to 10 words of the sub-frame 4 contain ionosphere and UTC time corrections and almanac of satellites 25 to 32 . These almanacs are similar to the ephemeris but give a less accurate position of the satellites and are valid for six days. The 3 to 10 words of the sub-frame 5 contain only the almanacs of different satellites in different frames.
The super frame contains twenty five consecutive frames. While the contents of the sub-frames 1 , 2 and 3 repeat in every frame of a superframe except the TOW and an occasional change of ephemeris every two hours. Thus the ephemeris of a particular signal from a satellite contains only the ephemeris of that satellite repeating in every sub-frame. However, almanacs of different satellites are broadcast in-turn in different frames of the navigation data signal of a given satellite. Thus the 25 frames transmit the almanac of all the 24 satellites in the sub-frame 5 . Any additional spare satellite almanac is included in the sub-frame 4 .
The almanacs and ephemeris are used in the computation of the position of the satellites at a given time. The almanacs are valid for a longer period of six days but provide a less accurate satellite position and Doppler compared to ephemeris. Therefore almanacs are not used when fast position fix is required. On the other hand, the accuracy of the computed receiver position depends upon the accuracy of the satellite positions which in-turn depends upon the age of the ephemeris. The use of current ephemeris results in better position estimation than one based on non-current or obsolete ephemeris. Therefore it is necessary to use current ephemeris to get a precise satellite position and hence the receiver position.
A GPS receiver may acquire the signals and estimate the position depending upon the already available information. In the ‘hot start’ mode the receiver has current ephemeris and the position and time are known. In another mode known as ‘warm start’the receiver has non-current ephemeris but the initial position and time are known as accurately as in the case of previous ‘hot start’. In the third mode, known as ‘cold start’, the receiver has no knowledge of position, time or ephemeris. As expected the ‘hot start’ mode results in low Time-To-First-Fix (TTFF) while the ‘warm start’ mode which has non-current ephemeris may use that ephemeris or the almanac resulting in longer TTFF due to the less accurate Doppler estimation or time required to download the new ephemeris. The ‘cold start’ takes still more time for the first position fix as there is no data available to aid signal acquisition and position fix.
It is not always possible to maintain a copy of current ephemeris in the receiver. This may be due to the fact that the receiver had no opportunity to download the ephemeris as it might have been powered off for a duration longer than four hours or because the received signal is very weak. There are US patents directed to providing assistance in fast position fix. Most of these patents deal with providing the ephemeris to the receiver through a wireless or wireline means. However, the ephemeris are valid over a limited period and is therefore of no use when a longer validity of the ephemeris expected. Some US patents and published US patent applications disclose methods of extending the validity of the ephemeris or orbit data. U.S. Pat. No. 6,437,734 discloses the transfer of navigation information from a sever to the GPS receiver using a polynomial method. This transfer is accomplished through the Internet. U.S. Pat. No. 6,542,820 discloses a method of extrapolating the ephemeris based on the historical tracking data or ephemeris. However, the extrapolation of the ephemeris is done at a server and the sets of predicted satellite orbit parameters valid for several days are sent to the navigation receiver from the server. Published U.S. patent application 2006/0055598 also discloses a similar method. The problem with these methods is that they require a central GPS receiver platform to collect historical navigation data and a server and communications system to predict and transfer the satellite orbit data to the intended navigation receiver.
Therefore, there is a need for a standalone navigation receiver that is capable of generating its own predicted satellite orbits without the need of connecting to a remote server and the associated communications system.
SUMMARY
Accordingly, the present invention provides methods and system for enabling a standalone navigation receiver capable of generating receiver specific predicted satellite orbits based on historical navigation data collected by and stored in the receiver. Thus, the navigation receiver is able to use predicted satellite orbits to obtain better TTFF and position accuracy without the need of connecting the receiver to a remote server and the associated communications system.
In an embodiment, a standalone navigation receiver having sufficient memory collects navigation data from navigation satellites whenever the receiver is tracking signals from the navigation satellites. The collected navigation data may include ephemeris. The receiver generates predicted satellite orbits using the collected navigation data. Under weak signal conditions when decoding of the navigation data is not possible, the receiver uses the predicted satellite orbits to predict the accurate satellite positions or the set of ephemeris and the associated pseudoranges. The predicted orbits may be accurate for several days without the reception of broadcast ephemeris.
The above and other advantages of embodiments of this invention will be apparent from the following more detailed description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating a GPS receiver according to an embodiment of the present invention.
FIG. 2 illustrates a receiver system according to an embodiment of the present invention.
FIG. 3 shows an exemplary satellite orbit with time stamps indicating the satellite's position at the respective time stamps.
FIG. 4 shows an exemplary Kalman filter for generating estimating parameters according to an embodiment of the invention.
DETAILED DESCRIPTION
FIG. 1 illustrates a receiver according to a preferred embodiment of the invention. An intermediate frequency (IF) signal input 101 enters a baseband section of the receiver from an analog-to-digital converter (ADC) output of a conventional RF front-end 100 . The IF input is multiplied in IF mixers 102 and 103 in-phase and in quadrature, respectively, with a local frequency signal generated by a direct digital frequency synthesizer (DDFS) 106 . This mixing involves multiplying the ADC output 101 by the local DDFS frequency in-phase which generates the in-phase component I 107 . In a parallel path the same signal 101 is multiplied by the DDFS frequency in quadrature (i.e., with a phase shift of 90 degrees) to produce quadrature component Q 108 . The DDFS 106 is driven by a carrier numerically controlled oscillator (NCO) 105 . In addition, carrier NCO 105 receives phase and frequency corrections from a processor 113 . Because of this correction, the DDFS frequency and phase is almost the same as that of the ADC output 101 . Thus the I and Q signals produced by the IF mixers 102 and 103 are at near zero carrier frequency after being low-pass filtered to remove the high frequency components which are at twice the IF frequency band.
The I and Q components 107 and 108 are correlated in correlators 109 and 110 , respectively, with a locally-generated PRN sequence generated by a PRN generator 111 . The PRN-sequence corresponds to the satellite whose signal is being processed by the baseband section at that time. The PRN sequence generator is driven by code NCO 112 . The local code frequency is made equal to the code rate of I and Q paths by corrective feedback from processor 113 to the code NCO 112 . In addition, processor 113 sends a signal to PRN code generator 111 to set the starting phase of the locally generated code. The NCO 112 provides the correct clock signals to correlators 109 and 110 . For example, NCO 112 provides a clock signal to generate two samples per PRN chip in the signal acquisition stage and three samples per chip during the tracking stage. SYS CLK 104 provides to NCO 105 and NCO 112 a common clock synchronization signal. The correlator outputs are then sent to processor 113 at every millisecond interval. The processor 113 is preferably a digital signal processor (DSP) core suitable for high speed arithmetic computations. Subsequent processing of the signals take place in the processor 113 , as will be described in detail below. Additional details of the receiver baseband section described above are contained in U.S. patent application Ser. No. 11/123,861 filed on May 6, 2005, the specification of which is incorporated herein by reference.
A DSP core of processor 113 receives one millisecond integrated (correlated) I and Q values from the GPS baseband section described above. In order to acquire a GPS signal in the DSP processor, all dwells (set of carrier frequency, code offset) are searched. This is a two-dimensional search. Coherent integration and non-coherent integration are two commonly used integration methods to acquire GPS signals. Coherent integration provides better signal gain at the cost of larger computational load, for equal integration times.
A GPS receiver uses the down-loaded ephemeris to accurately compute the position of the visible satellites. Based on these satellite positions, the position of the receiver is estimated. This computed position is more accurate if the ephemeris used is current. In the case of GPS the ephemeris is updated every two hours even though the ephemeris is valid for a period of four to six hours. If ephemeris is used beyond this period of four to six hours, it causes an offset in pseudorange where the pseudorange is the estimated distance of the satellite from the receiver with no corrections applied for the receiver clock drift, atmospheric delay, etc. In addition to the shift in the position, the estimated values of Doppler and Doppler rate are also not accurate with non-current ephemeris and result in a longer search time with a longer Time-To-First-Fix (TTFF). Thus, it is always necessary to download and use current ephemeris to minimize this position error and the TTFF. However, it is not always possible to have current ephemeris in the memory of the GPS receiver. One example is the case of a morning commute to the office where the GPS receiver is powered off for the remainder of the day and is not powered on again until the evening for the commute back home. The time gap in this case is more than four hours and the ephemeris becomes non-current. Use of this non-current ephemeris not only increases the TTFF but also results in position estimation with a shift and therefore a proper vehicle navigation can not be initiated. Further, there is considerable delay if one opts for new ephemeris download from each of the satellites involved. This download may require eighteen seconds or more for each satellite after the start of the signal tracking process. Further, the broadcast ephemeris need to be separately downloaded from each of the visible satellite.
To overcome the above problems associated with non-current ephemeris, the present invention provides techniques to generate sets of more precise ephemeris that are valid over a larger time interval, extending over several days. This new set of ‘generated ephemeris’ can be based on the sets of current and historical broadcast ephemeris and measurements such as pseudoranges collected by and stored at the receiver. In this disclosure, the set of present and historical broadcast ephemeris and measurements will be referred to as historical data. Further, the positioning device or GPS receiver is assumed to have enough memory to store the historical data of interest over a long period. The techniques of the present invention build satellite orbit models to fit the historical data. These models are then used to predict the Satellite Vehicle (SV) orbit and simultaneously generate the predicted ephemeris.
The historical data collection need not be carried out continuously over a long time interval. On the other hand, data collection preferably takes place whenever the receiver is in navigation mode. Thus collection preferably occurs at regular intervals of, e.g., once at a fixed time instance in every two hours. Alternatively, the collection may also be at the end of the present two hour interval and continue at the start of the next interval of new broadcast ephemeris. The broadcast ephemeris values are not stored whenever reception conditions do not allow proper downloading. In that case, the orbit model is built with available stored historical data.
In addition to the downloaded navigation data, some computed values such as pseudorange are stored in the database. These measured values reduce the computational load in the orbit determination.
FIG. 2 shows a navigation receiver system according to an embodiment comprising three modules: a local navigation database 204 , an orbit computation engine 205 and a position fix 203 modules. The first module 204 is a local navigation database of current and historical navigation information. The navigation information is obtained by signal observations and computed results. The signal observations are the data transmitted by the satellites which include the ephemeris, almanac, time and corrections to position and time for each of the satellites. The computed results include various satellite perturbation forces, satellite initial parameters such as mass, direction of motion etc., UTC and GPS time, and pseudoranges. The ideal satellite orbit will be modified by the perturbation forces. The navigation receiver receives navigation data such as ephemeris, almanac, timing information and some correction data shown as 202 from the GPS satellites 201 . Block 203 is the GPS signal receiver and position fix device which is the normally used form of the GPS receiver. Block 204 is the storage or database of the prior and current navigation data including manually input parameters such as masses of the earth, moon and planets, coefficients for relativistic effects, gravitational forces, etc. Block 205 is the orbit computation module which provides the needed computation capability for orbit determination.
The second module 205 is the satellite orbit computation module. This comprises the mathematical modules for generating the perturbation forces experienced by the navigation satellites, estimation of initial condition parameters and selected perturbation force parameters using the historical data, and calculation and extrapolation of the orbit coordinates with accuracy information. The orbit computation module may be implemented in software stored in memory on the receiver and executed by a processor of the receiver.
Because of perturbation forces the orbit deviates from the ideal orbit. The forces are due to the effects of the gravitational field of the sun, moon and other planets including the earth. In addition to these forces there also exist other forces such as non-spherical force due to earth shape, earth tide, sun radiation pressure, relativity effect and atmospheric drag. All of these factors may be taken into consideration when the satellite orbit is predicted. Available present day techniques may be used to compute these forces.
With a standalone GPS receiver, the available information is the broadcast ephemeris collected in the past and stored in the local navigation database of the receiver. In order to predict the satellite orbit at time t m from the last available broadcast ephemeris at a time t 0 , the following information may be prepared:
The transformation between the Earth Centered Earth Fixed (ECEF) coordinates u and the Earth Centered Inertial (J2000) coordinates x:
x=WRNP·u
The polar motion (W), earth roation (R), nutation (N) and precession (P) may be assumed to be known within the coming several years, in which case they do not need to be estimated in the mathematical modeling.
The forces on the satellite can be classified into two categories. One category ({umlaut over (x)} model ) can be modeled with enough accuracy and the other category ({umlaut over (x)} estimate ) needs to be estimated based on historical data. The total forces can be represented as:
x ( t m )= x ( t 0 )+∫ t 0 t m (∫ t 0 t {umlaut over (x)} ( t ) dt+{dot over (x)} ( t 0 ) dt
where x(t m ) and x(t 0 ) are the satellite coordinates at times t m and t 0 , respectively, {umlaut over (x)}(t) represents total forces as a function of time and {dot over (x)}(t 0 ) represents velocity at time t 0 .
The satellite coordinates in ECEF can be transformed from J2000:
u =( WRNP ) −1 ·x
The next step is to estimate the parameters (β) for the forces in {umlaut over (x)} estimate and satellite initial position x(t 0 ) and velocity {dot over (x)}(t 0 ).
The information from a standalone GPS receiver system provides historical broadcast ephemeris at t 0 , t −1 , . . . , t −n , and the mathematical model can be built as follows:
x ( t −n )= x ( t 0 )+∫ t 0 t −n (∫ t 0 t ( {umlaut over (x)} model ( t )+ {umlaut over (x)} estimate (β, t ) dt+{dot over (x)} ( t 0 ) dt
Therefore x(t 0 ), {dot over (x)}(t 0 ) and β can be estimated based on the above observation equation. The position x(t −n ) of the satellite at times t −n , can be obtained using historical broadcast ephemeris stored in the receiver.
With the initial satellite status (position x(t 0 ) and velocity {dot over (x)}(t 0 )) and β parameters, the satellite orbit can then be predicted with better accuracy.
The historical ephemeris of x(t −n ) has errors which is dependent on the age of the ephemeris. The other error sources are due to the residual errors from forces modeling which is proportional to the square of the integration time (t-t 0 ). Based on these errors the weight matrix of the x(t −n ) can be approximated in Kalman filtering or Least Square estimator.
There are at least two ways to compute the above integration in the receiver. One is the numerical integration using Runge-Kutta methods, Adams-Bashforth method, or any other numerical algorithms; the other way to derive the analytical formula for low order terms and simplify the numerical integration calculation load.
After the discrete satellite positions are predicted, the interpolation algorithms may be used to get satellite position at any time. Interpolation algorithms include Chebyshev polynomial interpolation, Lagrangian polynomial interpolation, or other interpolation methods. The satellite position can also be presented in the format of the satellite broadcast ephemeris which is valid at 4-6 hours. Thus the predicted satellite positions can be formatted into predicted ephemeris, which are valid for several days.
This method is illustrated in FIG. 3 where reference number 301 represents the orbit of the satellite. In FIG. 3 , t 0 is the current time and BC(0) is the corresponding broadcast ephemeris. The BC(0) may be represented as a sum of a function of satellite position, velocity, solar pressure, etc. and small error in these parameters. This error may be estimated by knowing the broadcast ephemeris during the past time stamps t −1 , t −2 , . . . t −n where n is the number of the prior ephemeris considered. A Kalman filtering technique or similar technique may be used for estimation.
FIG. 4 shows the inputs and outputs of an exemplary Kalman filter as used in an embodiment of the invention. The Kalman filter includes both the predictor and corrector. The inputs to the Kalman filter are the old or historical ephemeris and the initial values of the estimating parameters including perturbation forces. The Kalman filter uses the initial values of the estimating parameters to predict the satellite position at a past time t −1 . Based on the difference between the predicted position at t −1 and the position at t −1 obtained using broadcast ephemeris, the estimating parameters are modified or corrected to reduce the error. The satellite position is then predicted at past time t −2 using the modified estimating parameters. Based on the difference between the predicted position at t −2 and the position at t −2 obtained using broadcast ephemeris, the estimating parameters are further modified or corrected. This process is repeated for a set of historical satellite positions resulting in further refinement of the estimating parameters and better prediction accuracy. The output of the Kalman filter is the modified estimating parameters (position x(t 0 ), velocity {dot over (x)}(t 0 ) and β parameters). The calculation or extrapolation of the satellite orbit at future times, etc. t 1 , t 2 , etc. may be done using the modified estimating parameters. The estimation error computed by the Kalman filter provides accuracy information for the estimated satellite position.
The second embodiment of the calculation or extrapolation of the orbit is similar to the first embodiment except that analytical formula is used to generate the estimating parameters. A Chebyshev polynomial or Lagrangian polynomial or any other fitting/prediction function may be used to fit the estimating parameters using least square error criteria. These functions optimally fit the historic and predicted ephemeris data to a curve which represents the trajectory or orbit of the satellites.
The satellite clock offset is another parameter that needs to be precisely known for the position fix. The satellite clock offsets with the second order polynomial function is downloaded from the satellite navigation data and stored in the local navigation database. Based on all sets of satellite clock offsets, the satellite clock bias can also be fitted on a polynomial fitting function using least squares estimation algorithm. Thus, values for the satellite clock offsets in the future time can be extrapolated from the sets of satellite clock offsets stored in the local database. Any extrapolation algorithm with second order or higher order fitting functions may be used for the satellite clock offset prediction.
The above predicted satellite orbit may be computed according to a given schedule, e.g., every six hours or whenever the local navigation database is updated. The predicted satellite orbit is then stored in the local navigation database. This orbit is used whenever position is computed in the given interval. It may also be used in the generation of the next time interval orbit prediction if broadcast ephemeris are not available, e.g., during t 2 . The predicted satellite orbit can itself be in the navigation data format with orbits determined in terms of Eccentricity e s , square root of semi-major axis, correction terms, etc. to generate predicted ephemeris.
In an embodiment, the predicted satellite orbit is computed whenever new ephemeris for the corresponding satellite is downloaded and stored in the local database. This way, the predicted satellite orbit incorporates the latest ephemeris received by the receiver, thereby providing better accuracy. In another embodiment, the receiver uses the most accurate available ephemeris to compute satellite position, e.g., current ephemeris if stored in the local database or predicted ephemeris based on the predicted satellite orbit if current ephemeris is not stored in the local database.
The final module is the position fix module 203 . The above predicted ephemeris are used to accurately determine the position of the satellites and hence acquire the satellite signals. A Kalman filtering or least squares estimating algorithm is also used in the position fix module to derive the position from the noisy measurements. The Kalman filter may do this by receiving several consecutive pseudorange measurements to estimate the noise and correcting future measurements by removing this noise or error in the position computation. The Kalman filter takes into account the prior accuracy information of the orbit. Thus the biases in the ephemeris and the clock, which are the errors associated with the ephemeris prediction and with the satellite clock and hence with estimated time, determines the accuracy of the orbit and hence the receiver position. Based on the accuracy of the predicted ephemeris and the clock or time, a quality of position fix is also determined. The quality of position fix may be determined, e.g., by computing how the accuracy of the orbit and time affect the position fix computation. Thus this position fix also determines the associated quality of the position fix.
Although the present invention has been described in terms of the presently preferred embodiments, it is to be understood that the disclosure is not to be interpreted as limiting. Various alterations and modifications will no doubt become apparent to those skilled in the art after having read this disclosure. For example, although the above embodiments have been described using the GPS system as an example, the techniques and methods may be used for other global satellite navigational systems including GLONASS, Galileo, secondary systems such as WASS, EGNOS, and MSAS, as well as hybrids of the above systems. Accordingly, it is intended that the appended claims be interpreted as covering all alterations and modifications as fall within the spirit and scope of the invention.
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The present invention provides methods and system for enabling a standalone navigation receiver capable of generating receiver specific predicted satellite orbits based on historical navigation data collected by and stored in the receiver. Thus, the navigation receiver is able to use the predicted satellite orbits to obtain better Time-To-First-Fix (TTFF) and position accuracy without the need of connecting to a remote server and the associated communications system. In an embodiment, a standalone navigation receiver having sufficient memory collects navigation data from navigation satellites and generates predicted satellite orbits using the collected navigation data. Under weak signal conditions when decoding of the navigation data is not possible, the receiver uses the predicted satellite orbits to predict the accurate satellite positions or the set of ephemeris and the associated pseudoranges. The predicted orbits may be accurate for several days without the reception of broadcast ephemeris.
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This application is a continuation-in-part application of application Ser. No. 08/825,021 filed Mar. 26, 1997, now abandoned.
TECHNICAL FIELD OF THE INVENTION
The present invention relates to heat-insulating stock material and methods for producing the stock material and containers. More particularly, the present invention is directed to the formation of insulating stock material formed by selectively adhering a polymer film to a paperboard substrate and forming containers from the insulating stock material.
BACKGROUND OF THE INVENTION
Several types of heat-insulating containers have been used commercially to pack hot liquids. A polystyrene foam heat-insulating container is one example. It is prepared by casting unfoamed polystyrene into a mold, heating the resin under pressure to foam it, and removing the foamed resin from the mold. Alternatively, a foamed styrene sheet may be shaped into a container. An initial drawback of these types of containers is that their insulating characteristics are so efficient that the consumer can be lulled into a false sense of security because the outside of the cup is not hot while the temperature of the contents remain scalding. The container thus produced has outstanding heat-insulating properties but, on the other hand, it needs reconsideration from the viewpoint of saving petroleum resources or increasing the efficiency of incinerating waste containers. As a further problem, a slow, inefficient and high waste printing process is required to print on the outer surfaces of polystyrene foam heat-insulating containers since printing can only be effected after individual cups have been shaped. Further, the tapered surface of the container contributes to print blur at positions near the top and bottom of the container unless specialized and expensive printing technology is employed. As a further disadvantage, the outer surface of the foamed styrene heat-insulating container is often not sufficiently smooth to accept high resolution screen printing further affecting printability. Thus, the polystyrene foam containers suffer the disadvantage of low printability.
The conventional paper heat-insulating container can not be manufactured at low cost, and one reason is the complexity of the manufacturing process. One example is a container wherein the side wall of the body member is surrounded by a corrugated heat-insulating jacket. The process of manufacturing such containers involves additional steps of forming the corrugated jacket and bonding it to the outer surface of the side wall of the body member. One defect of this type of container is that letters, figures or other symbols are printed on the corrugated surface and the resulting deformed letters or patterns do not have aesthetic appeal to consumers. Another defect is that the jacket is bonded to the side wall of the body member in such a manner that only the valley ridges contact the side wall, and the bond between the jacket and the side wall is so weak that the two can easily separate. Often times, corrugated containers are not suitable for stacking and thus require large storage space.
U.S. Pat. No. 4,435,344 issued to Iioka teaches a heat-insulating paper container consisting of a body member and a bottom panel member, characterized in that at least one surface of the body member is coated or laminated with a foamed heat-insulating layer of a thermoplastic synthetic resin film whereas the other surface of the body member is coated or laminated with a thermoplastic synthetic resin film, a foamed heat-insulating layer of thermoplastic synthetic resin film or an aluminum foil. When manufacturing such a container, the water in the paper is vaporized upon heating, causing the thermoplastic synthetic resin film on the surface to foam. The container under consideration has the advantage that it exhibits fairly good heat-insulating properties and that it can be manufactured at low cost by a simple process. However, the thermoplastic synthetic resin film will not foam adequately if the water content in the paper is low. While high water content is advantageous for the purpose of film foaming, the mechanical strength of the container may deteriorate. Moreover, even if successful foaming is done, the thickness of the foam layer is uniform and cannot be controlled from one portion of the container to another. Further, the foam layer reaches an expansion limit regardless of the moisture content of the base layer.
In an effort to overcome the aforementioned shortcomings, U.S. Pat. No. 5,490,631 issued to Iioka discloses a heat-insulating paper container including a body wherein part of the outer surface of the body members provided with a printing of an organic solvent based ink. The body portion is subsequently coated with a thermoplastic synthetic resin film which when heated forms a thick foamed heat-insulating layer in the printed area of the outer surface whereas a less thick foamed heat-insulating layer is formed in the non-printed areas. Further, there are portions of the outer surface which remain unfoamed. In manufacturing a container in this manner, the printing is carried out on the paperboard layer and consequently viewing of the printed matter by the consumer is obstructed by the foamed insulating layer. Moreover, because the foamed layer overlying the printed areas are thicker than the remaining portions of the foamed layers, these areas will be even more obstructed. Consequently, this container suffers from similar drawbacks as those containers discussed hereinabove.
Another type of paper heat-insulating container has a “dual” structure wherein an inner cup is given a different taper than an outer cup to form a heat-insulating air layer. The two cups are made integral by curling their respective upper portions into a rim. The side wall of the outer cup is flat and has high printability, however, the two cups may easily separate. Another disadvantage is that the dual structure increases the manufacturing cost and thus the unit cost of the container. Moreover, the dual cup construction increases the stacking height of the cups and consequently increases packaging and shipping costs.
Accordingly, there is a need for insulated stock material and containers wherein the stock material can be manufactured in an economical manner such that the resultant containers formed from the insulating stock material provide the requisite insulating properties while readily receiving printed matter on the outer surface of the material.
SUMMARY OF THE INVENTION
A primary object of the present invention is to overcome the aforementioned shortcomings associated with the containers discussed hereinabove.
A further object of the present invention is to provide a heat insulating stock material which may be economically manufactured and readily formed into containers for receiving a hot liquid.
Yet another object of the present invention is to provide a decorative heat-insulating container and stock material for forming the same wherein the outer surface of the insulating material readily receives printed indicia.
Yet another object of the present invention is to provide a heat insulating container including a plurality of pockets which readily expand in response to a hot liquid being placed in the container thereby forming an insulating barrier between the hot liquid and the consumer.
Still another object of the present invention is to provide methods of forming the heat insulating stock material in a manner which adds little to the overall cost associated with the formation of such containers.
A still further object of the present invention is to provide a heat insulating container and stock material for forming the same which includes not only enhanced insulating characteristics but which provides for little increase in the stacking height of the containers.
These as well as additional advantages of the present invention are achieved by forming an insulating container comprising a container body having a side wall and a bottom wall with the one side wall including a base layer and an insulating layer on at least a portion of the base layer, preferably on an inside surface of the side wall. The insulating layer being selectively adhered to at least a portion of the base layer such that the selective adhering of the insulating layer to the base layer creates air pockets between the insulating layer and the base layer with the air pockets being expandable in response to contact with a heated liquid. Such a container is formed from an insulating stock material comprising a paperboard base layer and an insulating layer overlying at least a portion of at least of one surface of the base layer with the insulating layer being selectively adhered to the surface of the base layer forming enclosed regions between the base layer and the insulating layer. In order to ensure the formation of pronounced air pockets between the insulating layer and the base layer, the paperboard base layer may be debossed, creating debossed regions with the insulating layer being adhered over the openings of the debossed regions.
These as well as additional advantages of the present invention will become apparent from the following detailed description when read in light of the several figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial cross-sectional view of a container formed in accordance with the present invention.
FIG. 2 is a cross-sectional perspective view of stock material which may be used to form the container of FIG. 1 in accordance with one aspect of the present invention.
FIG. 3 is a schematic representation of the method used in forming the stock material of FIG. 2 .
FIG. 4 is a partial cross-sectional view of a container formed in accordance with an alternative embodiment of the present invention.
FIG. 5 is a cross-sectional perspective view of the stock material for manufacturing the container of FIG. 4 in accordance with the present invention.
FIG. 6 is a schematic representation of the method used in forming the stock material of FIG. 5 .
FIG. 7 is a partial cross-sectional view of a container formed in accordance with yet another alternative embodiment of the present invention.
FIG. 8 is a cross-sectional perspective view of the stock material for manufacturing the container of FIG. 7 in accordance with the present invention.
FIG. 9 is a schematic representation of the method used in forming the stock material of FIG. 8 .
FIG. 10 is a graphic illustration of the advantages achieved in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the several figures, the present invention will now be described in greater detail hereinbelow. When referring to the several figures, like reference numerals will be used to refer to like elements throughout the description.
Referring now to FIGS. 1, 2 and 3 , the initial embodiment of the present invention will be described in detail. As noted hereinabove, the present invention is directed to the formation of heat insulating containers and more particularly to the formation of an insulating stock material formed by selectively adhering a polymer film to a paperboard substrate and subsequently forming containers from the insulating stock material. Referring to FIG. 1, a container in the form of a conventional cup 10 is illustrated including a side wall 12 tapering slightly inwardly from an upper perimeter thereof to the bottom of the container. About the upper periphery of the container 10 is a brim curl 14 which aids in the consumption of the contents of the container. Secured to the bottom portion of the cylindrical side wall 12 is a bottom wall which may be secured to the cylindrical side wall 12 in a conventional manner.
Particularly with respect to the present invention, the container 10 is formed of a heat insulating stock material particularly illustrated in FIG. 2 . The heat insulating stock material 20 includes a base layer 22 formed of a paperboard material and a polymer film 24 which is selectively adhered to the surface of the paperboard substrate 22 . The particular sealing of the polymer film 24 to the paperboard substrate 22 will be discussed in greater detail hereinbelow with respect to the method of forming the heat insulating stock material, however, as can be seen from FIG. 2, the sealing of the polymer film 24 to the paperboard substrate 22 is carried out in a manner which presents a plurality of enclosed regions 26 which entrap air within the regions. As will be discussed in greater detail hereinbelow upon contact with a hot liquid, the enclosed regions 26 expand to form a heat insulating barrier between the hot liquid and the consumer. With respect to the several figures, the dimensions of the air pockets are exaggerated for clarity as well as the thickness of the material layers.
Provided on an opposing surface of the paperboard substrate 22 is a moisture and air impermeable coating 28 which is presently applied to paperboard containers in a conventional manner. As can be seen from FIG. 2, the polymer film 24 is pattern heat sealed to the surface of the paperboard substrate 22 thereby providing the enclosed regions 26 . It should be noted that the pattern may take on any configuration so long as a plurality of enclosed regions are formed.
With reference to FIG. 3, a schematic representation of the method of forming the heat insulating stock material 20 is illustrated. Therein, the paperboard substrate 22 is provided between a metal chill roll 30 and a rubber back-up roll 32 . The polymer sheet 24 may be provided in any conventional manner with an extruder 34 being illustrated in FIG. 3 . When being extruded, the polymer film 24 and preferably a polyethylene film may pass over additional chill rolls (not shown) if necessary prior to being directed to a nip region 36 between the metal chill roll 30 and back-up roll 32 . Preferably, the metal chill roll 30 includes a raised pattern which forms the pressure nip region 36 and seals the softened polymer film 24 to the paperboard substrate 22 at a high pressure which thereby forms the enclosed regions 26 . It should be noted that the paperboard substrate is previously coated with the impermeable coating 28 prior to being brought to the nip region 36 between the metal chill roll 30 and the back-up roll 32 . It should also be noted that while the impermeable coating 28 is illustrated as being applied to an opposing surface of the paperboard substrate 22 from the polymer film 24 , the impervious coating 28 may be applied to the same surface of the paperboard substrate 22 and underlie the polymer film 24 . This feature will be discussed in greater detail hereinbelow with respect to the embodiment illustrated in FIGS. 4-6. The impervious coating 28 aids in maintaining the air within the enclosed regions 26 .
As noted hereinabove, the metal chill roll 30 includes raised areas (not shown) which form the pattern illustrated in FIG. 2 . These raised areas provide a high pressure bond between the polymer film 24 and the paperboard substrate 22 in the nip region 36 formed between the patterned metal chill roll 30 and rubber back-up roll 32 . Accordingly, the polymer material which is not under high pressure due to the raised areas of the patterned metal chill roll 30 will not adhere to the paperboard substrate 22 and thus form the above-noted enclosed regions 26 . The degree of adhesion between the polymer film 24 and the paperboard substrate 22 in the sealed areas 38 may be controlled by a number of factors. Particularly, the temperature of the polymer film being extruded from the extruder 34 , the position of the extruded polymer film 24 with respect to the nip region 36 between the metal chill roll 30 and the rubber back-up roll 32 , the nip pressure applied in the nip region 36 , the particular temperature of the chill roll, the type of polymer material used, the surface treatment of the paperboard as well as the atmosphere surrounding the nip region 36 . All of these factors must be taken into account when adhering the polymer film 24 to the paperboard substrate 22 . Particularly, the polymer film 24 cannot be of a temperature which would permit the entire polymer film 24 to inadvertently adhere to the paperboard substrate 22 which would have the effect of eliminating the enclosed regions 26 . Moreover, the adhesion between the polymer film 24 and the paperboard substrate 22 in the sealed areas 38 must be controlled so as to properly adhere the polymer film 24 to the paperboard substrate 22 so as to ensure the formation of the enclosed regions 26 which retain a sufficient amount of air.
Alternatively, the rubber back-up roll 32 may include raised areas thus applying pressure in the nip region 36 in selected areas. Further, both the metal roll 30 and the rubber back-up roll 32 may include such raised areas. The particular pattern formed in each roll will be dependent on the intended use of the insulating stock material. With respect to the rubber back-up roll 32 , it is necessary that the roll be of sufficient hardness to receive and maintain the pattern when under pressure in the nip region 36 . In that forming the pattern in the rubber back-up roll by laser engraving or other means is easier and less expensive than forming such pattern in a metal roll, the costs associated with the entire process may be reduced by using patterned rubber back-up rolls.
When the heat insulating stock material 20 is exposed to heat such as when the stock material is utilized to form the container 10 as illustrated in FIG. 1 and the container is filled with a hot liquid, the unbonded areas of the polymer film 24 of each of the enclosed regions 26 will expand with the expansion of the air provided in the air space between the paperboard substrate 22 and the polymer film 24 in the enclosed regions 26 along the inside wall of the container 10 . This expansion provides heat insulating characteristics which maintains an outer surface of the container 10 at an acceptable temperature level even though the contents the container may reach a temperature as high as 180-200° F. It should be noted that the container 10 can be formed from the insulating stock material such that the polymer film 24 and consequently the enclosed regions 26 are on an outside surface of the container 10 .
With reference now to FIGS. 4-6, a container substantially identical to that illustrated in FIG. 1 is set forth with the exception of the formation of larger enclosed air space regions. As with the previous embodiment, the container 100 is formed of a heat insulating stock material formed by selectively adhering a polymer film to a paperboard substrate and subsequently forming such containers from the heat insulating stock material. Referring to FIG. 4, as with the previous embodiment, the container includes a side wall 112 tapering slightly inwardly from an upper perimeter thereof to the bottom of the container. About the upper periphery of the container is a brim curl 114 which aids in the consumption of the contents of the container. Secured to the bottom portion of the cylindrical side wall 112 is a bottom wall which is provided in a conventional manner.
Again, the container 100 is formed from a heat insulating stock material, particularly, stock material as illustrated in FIG. 5 . The heat insulating stock material 120 includes a base layer 122 formed of a paperboard material and polymer film 124 which may be selectively adhered to the surface of the paperboard substrate 122 . This sealing of the polymer 124 to the paperboard substrate 122 is carried out in a manner which as with the previous embodiment presents a plurality of enclosed regions 126 which entrap air within the regions. However, as can be appreciated from FIG. 5, the volume of the enclosed regions 126 is larger than that of the previous embodiment. The particular method for forming such enlarged enclosed regions 126 will be discussed in greater detail hereinbelow.
It is to be appreciated, as with the previous embodiment, that the paperboard substrate 122 includes a moisture and air impermeable coating 128 , which as can be seen from FIG. 5, is applied to the same surface of the substrate 122 as the polymer film 124 . While the impermeable coating 128 may be applied to the opposing surface as is illustrated in FIG. 2, by providing the impermeable coating 128 adjacent the polymer film 124 , a better air retention in the enclosed regions is achieved and better adhesion of the polymer film 124 in the sealing areas 138 is realized. Further, if the impervious coating 128 is applied to the outer surface, it may be necessary to also apply an impervious coating to the inner surface to assure that the container formed from the stock material has a sufficient moisture barrier. However, this depends on which surface of the substrate 122 the polymer layer 124 is adhered to.
With reference to FIG. 6, a schematic representation of the method for forming the insulating stock material 120 is illustrated. As with the previous embodiment, the paperboard substrate 122 is provided between a metal chill roll 130 and a rubber back-up roll 132 . Similarly, the polymer sheet 124 which may be provided in any conventional manner is extruded from the extruder 134 . Again, like the previous embodiment, when extruded, the polymer film 124 , which is preferably a polyethylene film, passes over a portion of the metal chill roll 130 to a nip region 136 formed between the metal chill roll 130 and the back-up roll 132 . Additionally, the metal chill roll 130 includes recessed areas 140 which may be more defined than those of the chill roll 30 illustrated in connection with the previous embodiment thereby forming extended raised areas 142 . As with the previous embodiment, the raised areas 142 provide a high-pressure bond between the polymer film 124 and the impermeable coating 128 in the nip region 136 formed between the metal chill roll 130 and the rubber back-up roll 132 . Unlike the previous embodiment, FIG. 6 includes a blower 144 which directs air under pressure through a nozzle and impinges on the heated polymer film 124 in order to force the heated polymer film into the recessed areas 140 of the metal chill roll 130 . In doing so, more pronounced and larger enclosed regions 126 are formed. Again, because the polymer material which is blown into the recess areas 140 is not subjected to high pressure as is the material adjacent the raised areas 142 of the metal chill roll 130 in the nip region 136 , the material in the recessed areas 140 will not adhere to the impermeable coating 128 , thus readily forming the above-noted enclosed regions 126 . Again, the degree of adhesion between the polymer film 124 and the impermeable coating 128 in the sealed areas 138 can be controlled by the factors alluded to in connection to the previous embodiment. Particularly, these factors are controlled such that the polymer film 124 is not of a temperature which would permit the entire polymer film to inadvertently adhere to the impermeable coating 128 . Further, the adhesion between the polymer film 124 and the moisture impermeable coating 128 must be of a degree which ensures the formation of the enclosed regions 126 in order to form the requisite heat insulating substrate.
As with the previous embodiment, the rubber back-up roll 132 may include raised areas thus applying pressure in the nip region 136 in selected areas. Further, both the metal roll 130 and the rubber back-up roll 132 may include such raised areas. The particular pattern formed in each roll will be dependent on the intended use of the insulating stock material. With respect to the rubber back-up roll 132 , it is necessary that the roll be of sufficient hardness to receive and maintain the pattern when under pressure in the nip region 136 . Again, because forming the pattern in the rubber back-up roll by laser engraving or other means is easier and less expensive than forming such pattern in a metal roll, the costs associated with the entire process may be reduced by using patterned rubber back-up rolls.
When the heat insulating stock material 120 is exposed to heat such as when the stock material is utilized to form the container 110 as illustrated in FIG. 1 and the container is filled with a hot liquid, the unbonded areas of the polymer film 124 of each of the enclosed regions 126 will expand with the expansion of the air provided in the air space between the paperboard substrate 122 and the polymer film 124 (or between the polymer film 124 and the impervious coating 128 , depending on which surface the coating and polymer layers are applied) in the enclosed regions 126 along the inside wall of the container 110 . This expansion provides heat insulating characteristics which maintains an outer surface of the container 110 at an acceptable temperature level even though the contents the container may reach a temperature as high as 180-200° F. This feature being best illustrated in FIG. 10 which is a graphical representation of sidewall temperatures of containers formed in accordance with the present invention as compared to that of conventional containers. As noted in FIG. 10, the upper surface of containers formed in accordance with the present invention having a large bubble film on the inside surface of the container exhibits a surface temperature of approximately 155° as compared to 190° for a conventional polyethylene coated cup. It is only after approximately 20 minutes of standing time that the temperature of the conventional polyethylene coated cup reaches that of the cup including a large bubble film on the inside surface of the container. Again, as noted hereinabove, the container 110 can be formed from the insulating stock material such that the polymer film 124 and consequently the enclosed regions 126 are on an outside surface of the container 110 .
Referring now to FIGS. 7, 8 and 9 , and the still further alternative embodiment of the present invention is set forth therein. As with the previous embodiments, FIG. 7 illustrates a container 210 including side wall 212 tapering slightly inwardly from an upper perimeter thereof to the bottom of the container. About the upper periphery of the container 210 is a brim curl 214 which aids in the consumption of the contents of the container. Likewise, secured to the bottom portion of the cylindrical side wall 212 is a bottom wall which may be secured to the cylindrical side wall 212 in any known manner.
Again, the container 210 is formed of a heat insulating stock material which is best illustrated in FIG. 8 . The heat insulating stock material 220 includes a base layer 222 formed of a paperboard material and a polymer film 224 which is adhered to raised portions 231 of the paperboard substrate 222 . While not particularly illustrated in FIG. 8, the paperboard substrate 222 may include a moisture and air impermeable coating on either or both surfaces of the paperboard substrate.
With reference to FIG. 9, a schematic representation of the method of forming the heat insulating stock material 220 is illustrated therein. Like the previous embodiment, the paperboard substrate 222 is provided between a metal chill roll 230 and back-up roll 232 , however, also provided is an embossing roll 233 including protuberances 235 which extend outwardly from a surface of the embossing roll 233 and which mate with female detents 237 formed in the back-up roll 232 . While the back-up roll 232 preferably includes the female detents 237 , the back-up roll may be a rubber back-up roll which cooperates with the protuberances 235 in order to form the debossed regions within the paperboard substrate. The debossed regions 227 are best illustrated in FIG. 8 and form air pockets 229 in the paperboard substrate 222 . Once formed, the polymer film 224 , which is extruded from the extruder 234 passes adjacent the metal chill roll 230 and is pressure sealed to the raised portions 231 of the paperboard substrate 222 in the nip region 236 , thus forming the air pockets 229 which promote the heat-insulating characteristics of the stock material 220 . Once again, the degree of adhesion between the polymer film 224 and the raised portions 231 of the paperboard substrate 222 may be controlled by a number of factors. As with the previous embodiments, these factors include the temperature of the polymer film being extruded from the extruder 234 , the position of the extruded polymer film 224 with respect to the nip region 236 between the metal chill roll 230 and back-up roll 232 , the nip pressure applied in the nip region 236 , the particular temperature of the metal chill roll 230 , the type of polymer material used, the surface treatment of the paperboard substrate 232 as well as the atmosphere surrounding the nip region 236 . All of these factors must be taken into account when adhering to the polymer film 224 to the paperboard substrate 222 . Again, it is clear that it is necessary that sufficient adhesion of the polymer film 224 to the raised regions 231 take place in order to properly form the air pockets 229 . As noted hereinabove, the paperboard substrate 222 may include an impermeable coating which, would preferably, be applied to the surface of the paperboard substrate adjacent the polymer film 224 in order to promote the adhesion of the polymer film 224 to the substrate thereby forming the air pockets 229 between two impermeable layers.
Again, when the heat insulating stock material 220 is exposed to heat such as when the stock material is utilized to form the container 210 and the container is filled with a hot liquid, the portions of the polymer film 224 overlying the air pockets 229 will expand in response to the expansion of the air within the air pockets 229 thus providing the requisite heat insulating characteristics. Additionally, any configuration may be utilized in forming the debossed regions. Accordingly, a decorative debossed pattern may be provided on an outer surface of the container 210 in order to enhance the acceptability of the container by the consumer. Further, the rough textured surface will aid in the grasping of the container by the consumer.
Accordingly, as can be seen from the foregoing description, insulated stock materials and containers are set forth wherein the stock material can be manufactured in an economical manner such that the resultant containers formed from the insulating stock material provide the requisite insulating properties while adding insignificantly to the overall costs associated with the manufacture of such stock materials or containers.
While the present invention has been described in reference to preferred embodiments, it will be appreciated by those skilled in the art that the invention may be practiced otherwise than as specifically described herein without departing from the spirit and scope of the invention. It is, therefore, to be understood that the spirit and scope of the invention be only limited by the appended claims.
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An insulating paperboard container is disclosed including a container body having a side wall and a bottom wall with the one side wall including a base layer and an insulating layer on at least a portion of the base layer, preferably on an inside surface of the side wall. The insulating layer being selectively adhered to at least a portion of the base layer such that the selective adhering of the insulating layer to the base layer creates air pockets between the insulating layer and the base layer with the air pockets being expandable in response to contact with a heated liquid. Such a container is formed from an insulating stock material comprising a paperboard base layer and an insulating layer overlying at least a portion of at least of one surface of the base layer with the insulating layer being selectively adhered to the surface of the base layer forming enclosed regions between the base layer and the insulating layer. In order to ensure the formation of pronounced air pockets between the insulating layer and the base layer, the paperboard base layer may be debossed, creating debossed regions with the insulating layer being adhered over the openings of the debossed regions.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an image pickup apparatus, and, more particularly to an image pickup apparatus for a TV camera which enables the most favorable exposure when humans are the subject of the image.
2. Description of the Related Art
There is a type of image pickup apparatus for a TV camera which automatically controls exposure at the most suitable level, it being classified into two types as follows: that is, a full-plane average light measuring type, and a center-weighted light measuring (spot measuring) type.
FIG. 1 is a schematic view illustrating an essential portion of a conventional image pickup apparatus. Referring to FIG. 1, an operation will be briefly described.
Referring to FIG. 1, reference numeral 101 represents a lens, and reference numeral 102 represents a diaphragm (iris) for controlling the quantity of light. Reference numeral 103 represents an image pickup element, reference numeral 104 represents an amplifier, and reference numeral 340 represents a gate circuit. Reference numeral 330 represents an integrator, reference numeral 181 represents a comparator, reference numeral 112 represents an iris driving circuit, and reference numeral 350 represents a gate signal generator.
Incidental light from a subject, via the lens 101, reaches the iris 102 at which the quantity of light is adjusted properly, and is introduced into the image pickup element 103. Next, a signal voltage (current) in accordance with the light from the subject is obtained. This signal is amplified by the liner amplifier 104 so as to be introduced into a monitor 104" via the ensuing processing circuit 104'. The gate circuit 340 controlled by the gate signal generator 350 determines a light measuring frame of the picture plane for the output signal from the amplifier 104. Only the signal within this light measuring frame is introduced into the integrator 330 where the same is integrated. The thus-integrated signal is compared with a reference level 182 by the comparator 181, and the output therefrom controls the iris 102 via the iris driving circuit 112. At this time, if the gain of the comparator 181 is sufficiently great, the iris 102 is controlled by a controlling loop thereof in such a manner that the integrated value of the image signal within the light measuring frame becomes the same as the reference value 182. If the light measuring frame determined by the gate circuit 340 comprises the entire picture plane, the system can be called a full-plane average light measuring type, while the system can be called a center-weighted light measuring or the spot measuring type. In a case of the center-weighted light measuring method, weighting is sometimes performed so as to make the central portion of the picture plane maximum. Since such weighting of the type described above cannot be performed by a mere gate circuit shown in FIG. 1, the product of the image signal and the weight signal needs to be obtained by using, for example, a multiplier.
However, a conventional light measuring method of the type described above involves the following problems: that is, in the full-plane average light measuring, since the subject image disposed against the light exhibits great luminance in the portion against the light, the diaphragm moves to be closed if the diaphragm is controlled by an averaged signal, causing for the subject image to be darkened and hidden.
On the other hand, in a case where a brilliant subject image is disposed in front of a dark background, the diaphragm is moved in the direction to be opened since the average level of the image signal is reduced. Therefore, the subject image becomes excessively highlighted.
In a case where the center-weighted light measuring method, the most suitable exposure can be obtained when the subject image is disposed at the central portion of the picture plane. However, if the subject image deviates off the central portion, the similar phenomenon to the full-plane average light measuring occurs. That is, in a case where the subject is disposed against light, the subject becomes dark and hidden, while in a case where the same is disposed in the dark background, the subject image becomes excessively highlighted.
In particular, since a video camera of the type described above performs the signal detection in response to a luminance signal lacking a red or blue component, the diaphragm cannot be adjusted suitably if the color of the subject image disposed in the above-described specific portion is thick (in particular in a blue of red case), causing the diaphragm to be excessively opened.
As described above, in the conventional image pickup apparatus, since signal detection is performed in response to the luminance signal lacking a blue or red component, a problem arises in that the degree of diaphragm setting cannot be suitably adjusted depending upon the color of the subject image when the incidental light is diaphragm-controlled by using a specific portion of the image signal.
SUMMARY OF THE INVENTION
To this end, an object of the present invention is to provide an image pickup apparatus capable of overcoming the above-described problems experienced with the conventional apparatus, this image pickup apparatus being capable of enabling the most suitable exposure regardless of the position and the background of the subject image.
Another object of the present invention is to provide an image pickup apparatus capable of overcoming the above-described problems, this image pickup apparatus being capable of enabling the most suitable exposure when humans are subject of the image.
In order to achieve the above-described objects, an image pickup apparatus according to an embodiment of the present invention comprises: determining means for picking up a plurality of color information signals from the image pickup element and comparing the color information signal with a predetermined reference value for the purpose of determining that the same reaches a predetermined level, and control means for controlling the exposure of the image pickup element in accordance with the result of the determination by changing the quantity of integration of the image pickup signal.
As a result of the thus-obtained exposing mechanism controlling method, the most suitable exposure can be always obtained when the human's skin or the like is the subject of the image.
Furthermore, in order to achieve the above-described objects, an image pickup apparatus according to another embodiment of the present invention comprises: diaphragm control means for controlling the diaphragm by picking up a signal obtained from an image pickup element, compensation signal generating means for generating a compensation signal in accordance with color signal information of the picked up signal, whereby the control value of the diaphragm control means is compensated in response to the compensation signal from the compensation signal generating means.
Other objects and characteristics of the present invention will be apparent from the following description of the specification and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates schematically an essential portion of a conventional image pickup apparatus.
FIG. 2 illustrates an image pickup apparatus according to an embodiment of the present invention.
FIG. 3 illustrates the position of the skin color and the quadrant including the skin color on the color difference signal coordinate.
FIG. 4 is a block diagram illustrating an essential portion of an image pickup apparatus according to a second embodiment of the present invention.
FIG. 5 is a block diagram illustrating in detail an essential portion of the compensation signal generator shown in FIG. 4.
FIG. 6 illustrates the value of the compensation signal Vc when the value of the color difference signals R-Y and B-Y shown in FIG. 5 are changed.
FIG. 7 is a block diagram illustrating in detail an essential portion of a compensation signal generator shown in FIG. 4 according to another embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 2 illustrates an image pickup apparatus according to an embodiment of the present invention. Referring to this figure, reference numeral 105 represents a processing circuit for processing an amplified video signal and for obtaining a luminance signal Y and color difference signals R-Y and B-Y. Reference numeral 106 represents an encoder for obtaining output signals of NTSC or PAL system in response to the luminance signal and the color difference signals obtained by the processing circuit 105. Reference numeral 107 represents an output terminal of the encoder 106. Reference numerals 121 and 122 represent comparators to which the above-described color difference signals R-Y and B-Y are respectively input, and for outputting them after making comparison with reference levels 131 and 132. Reference numeral 141 represents a logical product (AND) circuit to which the outputs from the above-described two comparators 131 and 132 are input. Reference numeral 152 represents a switch controlled to be closed when the output from the above-described AND circuit 141 is at a low level. Reference numeral 162 represents a first integrator for integrating the video signal 190 which has not yet been processed by the processing circuit 105. Reference numeral 151 represents a switch which is closed when the output from the AND circuit 141 is at a high level. Reference numeral 163 represents a second integrator for integrating the video signal 190 input via the above-described switch 151. Reference numeral 170 represents a mixer for mixing the outputs from the first integrator 162 and the second integrator 163, wherein the output from the first integrator 162 is arranged to display larger mixture ratio than that of the second integrator 163. Reference numeral 181 represents a comparator for performing comparison the output from the above-described mixer 170 with a reference voltage 181. Reference numeral 112 represents a driving circuit for driving an iris 102 by receiving the output from the comparator 181. The same reference numerals as those in FIG. 1 represent the same or equivalent portions.
In the circuit shown in FIG. 2, light from the subject of the image is made incident via a lens 101, and its quantity is adjusted to become most suitable. The light reaches an image pickup element 103. An electric signal corresponding to the quantity of the incident light from the corresponding image points of the subject of the image is picked up from each of picture elements, which are disposed on a plane, of the image pickup element 103. The thus-picked up electric signals are amplified by the amplifier 104, and are supplied to the processing circuit 105 wherein they are subjected to a gamma correction or the like. Next, a luminance signal Y and color difference signals R-Y and B-Y are processed in a matrix circuit in the processing circuit 105. The comparator 121 compares the value of the color difference signal R-Y with the reference value 131. If the value of the color difference signal R-Y is positive, the output of the comparator 121 becomes high level, while the same becomes low level if it is negative. The comparator 122 compares the value of the color difference signal B-Y with the reference value 132. If the value of the color difference signal B-Y is negative, the output becomes high level, while the same becomes low level when it is positive. If both the outputs from the comparators 121 and 122 are at a high level (i), the output from the AND circuit 141 also becomes high level so that the luminance signal 190 is supplied to the integrator 163, and simultaneously the switch 152 is opened to stop supply of the pre-processed luminance signal 190 to the integrator 162. If both of them are not at a high level (ii), the output from the AND circuit 141 becomes low level, causing the switch 151 to be opened to stop supply of the luminance signal 190 to the integrator 163, and simultaneously the switch 152 is closed to supply the luminance signal 190 to the integrator 162 wherein it is integrated.
The above-described process of detecting the level of the color difference signal and supplying the luminance signal 190 to each of the integrators 162 and 163 are intended to select information on the luminance of the subject of the image including the color near skin color.
FIG. 3 illustrates the position of the skin color and the quadrant including the former in the color difference signal coordinate. Reference numeral 201 represents a quadrant including skin color on the quadrant. Reference numeral 202 represents the coordinate for skin color, wherein the axis of ordinate represents R-Y, while the axis of abscissa represents B-Y. Referring to FIG. 3, skin color is present in the quadrant where the color difference signal R-Y is positive, while the color difference signal B-Y is negative.
Accordingly, by subjecting to the above-described processes by the circuit shown in FIG. 2, the luminance signals representing the subject of the image ranging from yellow to red are integrated by the integrator 163, while the luminance signals representing other color and no-color are integrated by the integrated by the integrator 162. Therefore, as described above, by mixing the output from the integrator 163 and the output from the integrator 162 in such a manner that the former is relatively larger than the latter by the mixer 170, the iris 102 can be controlled to take preference of the color in the quadrant including skin color.
As described above, according to this embodiment of the present invention, the most suitable exposure can be always obtained when the subject of the image is of the color near skin color from yellow to red.
FIG. 4 is a block diagram illustrating an essential portion of an image pickup apparatus according to a second embodiment. Reference numeral 101 represents a lens. Symbol EX represents an exposing member including a diaphragm for changing the quantity of incident light and/or a light shielding member such as a shutter. Reference numeral 103 represents an image pickup element comprising a CCD or MOS and a driver for the same. Reference numeral 104 represents an amplifier. Reference numeral 205 represents a Y-C separation circuit for separating the luminance signal Y and the color difference signals R-Y and B-Y from an input signal S by using a sample and hold circuit and a low-pass filter. Reference numeral 105' represents a processing encoder for synthesizing a standard TV signal from the luminance signal Y and the color difference signals R-Y and B-Y. Reference numeral 107 represents an output terminal. Reference numeral 207 represents a compensation signal generator for generating a compensation signal Vc from the color difference signals R-Y and B-Y. Reference numeral 209 represents a gate circuit for cutting the input signal S and having an integrating circuit. Reference numeral 210 represents a sensitivity control circuit for controlling the sensitivity of the image pickup apparatus by comparing the signal Vs from the gate circuit 209 with the compensation signal Vc. Reference numeral 211 represents a gate signal generator for generating a gate signal g which represents the level of the portion to be light-measured.
With the image pickup apparatus shown in FIG. 4, the image of the subject of the image (omitted from the illustration) passes through the lens 101 wherein the quantity of the light and the time period of incidence of the same are controlled by the exposing member EX so that the same is imaged and photoelectrically-converted to become an image pickup signal, and it is provided an an output. The thus-output image pickup signal is amplified by the amplifier 104. The output s of the amplifier 104 is separated into the luminance signal Y and the color difference signals R-Y and B-Y by the Y-C separation circuit 205, and is synthesized to become the standard TV signal by the processing encoder 105'. The thus-synthesized standard TV signal is output by the output terminal 107 to a peripheral equipment. The output s of the amplifier 104 is also input to the gate circuit 209 where only the portion of the same corresponding to the gate signal g can pass through the gate circuit 209. The thus-passed signal is, in the form of the signal Vs, input to the sensitivity control circuit 210. The color difference signals R-Y and B-Y are also input to the compensation signal generator 208 so that the compensation signal Vc is generated and is input to the sensitivity control circuit 210. The sensitivity control circuit 210 compares the average value of the signal Vs with the compensation signal Vc for controlling the exposing member EX, the sensitivity of the image pickup element 103 itself, the photoelectric conversion storing time of the image pickup element 103, the gain of the amplifier 104, or the combination of them. The exposing member EX, the image pickup element 103, the amplifier 104, the gate circuit 209 and the sensitivity control circuit 210 form a feed-back loop which acts to making the level of average value of the signal Vs and that of the compensation signal Vc coincide with each other.
FIG. 5 is a block diagram illustrating the details of the compensation signal generator 208 shown in FIG. 4. Reference numerals 220 and 222 represent positive clip circuits, reference numerals 221 and 223 represent negative clip circuits, and reference numeral 224 and 225 represent inverting amplifiers. Reference numerals 226, 227, 228, and 229 each represent a multiplier for multiplying constants K 1 , K 2 , K 3 and K 4 . Reference numeral 230 represents an adder, reference numeral 231 represents a reference voltage, and reference numeral 232 represents a gate circuit. Only the negative portion of the color difference signal R-Y input by the Y-C separation circuit 205 shown in FIG. 4 is picked up by the positive clip circuit 220. The thus-picked up portion is multiplied by K 1 by the multiplier 226. The thus-multiplied portion is input to the adder 230. On the other hand, only the positive portion of the same is picked up by the negative clip circuit 221, and is inverted by the inverting amplifier 224. Then it is multiplied by K 2 by the multiplier 227, and is input to the adder 230. Similarly, the negative portion of the color difference signal B-Y picked up by the positive clip circuit 222 is multiplied by constant K 3 by the multiplier 228, while the positive portion of the same picked up by the negative clip circuit 223 is inverted by the inverting amplifier 225. Then it is multiplied by constant K 4 by the multiplier 229, and is input to the adder 230. The adder 230 adds the input from each of the above-described multipliers 226, 227, 228 and 229 and the reference voltage 231 so as to output the results a the addition. As a result of this, only the portion represented by the gate signal g is output from the gate circuit 232 in the form of the compensation signal Vc. The constants K 1 to K 4 are defined as follows. Assuming that the level of the output S of the amplifier 104 at the time of white subject is imaged is 1, and the level of the output S of each subject R (red), G (green), and B (blue) are S R , S G and S B , respectively:
S R =0.3
S G =0.6
S B =0.1.
Each of S R , S G and S B is smaller than 1 although this value depends upon the type of the color filter of the image pickup element 103. Therefore, if the value of the compensation signal Vc at this time becomes the same as each of S R , S G and S B , the proper level can be obtained. In order to realize this state, the following value of the constants K 1 , K 2 , K 3 and K 4 are obtained.
K 1 =0.33
K 2 =1
K 3 =0.33
K 4 =1
FIG. 6 shows the value of the compensation signal Vc when the value of the color difference signals R-Y and B-Y shown in FIG. 5 are changed. When the color difference signal R-Y=0 and B-Y=0, the compensation signal Vc=1. The value of the compensation signal Vc becomes smaller in accordance with increase in thickness of color.
FIG. 7 is a block diagram illustrating the details of an essential portion of a compensation signal generator 208 according to another embodiment. Reference numerals 241 and 242 represent analog-digital converters (A/D converters). Reference numeral 243 represents a read only memory (ROM) for changing a table. Reference numeral 244 represents a latch circuit, and reference numeral 245 represents a digital-analog converter (D/A converter). The input color difference signals R-Y and B-Y are each converted to a digital signal by the A/D converters 241 and 242, and are, in the form of the address signal, input to the table-changing ROM 243. Since the value shown in FIG. 6 is written as the table data in the ROM 243, the data output corresponding to the value of the color difference signals R-Y and B-Y can be obtained. This data output is converted, through the latch circuit 244, by the D/A converter 245 to the compensation signal Vc in the analog form. The color signal is controlled by the gate signal g in the latch circuit 244 so that the data output of only the portion corresponding to the gate signal g is picked up. The thus-picked up compensation signal Vc is input to the sensitivity control circuit 210 shown in FIG. 4 so that it is processed.
Although in the embodiment shown in FIG. 4, the input of the compensation signal generator 208 comprises the color difference signals R-Y and B-Y, it may be an I signal, Q signal, primary color signal or the complementary color signal. Furthermore, the gate signal 209 may act to change the output value which has been weighted in accordance with the level of the gate signal as an alternative to a circuit only performing cutting.
Although the described sensitivity control circuit 210 comprises the feed-back type exposure controlling circuit, it can be applied to the method in which a photosensor is individually provided from the image pickup element for the purpose of controlling the sensitivity in accordance with the specific color component of the photosensor output.
Furthermore, the exposing member EX is not limited to the mechanical diaphragm or shutter, it can be applied to the same performing electrical shutter action or the same which electrically and physically changes the transmissivity.
As described above, according to the first and second embodiments of the present invention, the image pickup apparatus in which error in the luminance level due to the color of the subject can be prevented can be obtained.
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An image pickup apparatus for outputting an image pickup signal by forming an image of a subject on an image pickup element through an optical system includes a determining circuit for picking up a plurality of color information signals from the image pickup element, comparing the color information signals with a predetermined reference value to determine that the color information signals reach a predetermined level and detecting quantity of a skin color signal component; and a control circuit for controlling the exposure of the image pickup element in accordance with the result of the determination.
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BACKGROUND OF THE INVENTION
This invention relates to soil probes and particularly to a water jet sediment probe to determine, for example, the thickness of sand and other sediments on a beach overlying bedrock or the depth and type of sediment beneath a seafloor, etc.
Frequently, it is necessary to determine the depth of sand or various types of sediment on a beach or the seafloor in the vicinity of a beach for purposes of installing piles or other devices in the construction of piers and causeways and other structures. Also, it may be desirable to know the types and depths of sediment on a seafloor prior to installation of propellant embedded anchors and the like. An experienced operator while spudding a probe pipe into sediment can estimate the types of sediment being penetrated by feeling the vibrations transmitted from the lower tip of the probe pipe as it passes through the sediment layers.
A sediment probe using a water jet, also known as a wash pipe, generally consists of a rigid length of metal pipe, a flexible hose, and a source of water under pressure (from a water pump), Water being expelled under pressure from the end of the metal pipe or a jet nozzle at the end of the metal pipe operates to displace sediment or soil as it is being spudded (i.e., pushed) into the sediment by an operator. Soil is liquified at the point of entry and remains liquified ("quick") as long as water is continued to be pumped into the hole from the probe. The length of the metal pipe is limited by the operator's strength and height. A ten foot length of pipe is about the maximum practical limit for one person to work with and handle without assistance. A twenty-foot length of pipe can be used if guy lines are used to hold the pipe vertical, but such lengths require at least three guy line tenders in addition to the operator (spudder). Also, it is impossible to bore a deep hole using several sections of short pipe connected one at a time, because when water circulation is interrupted to make a pipe connection the sand, gravel, pebbles and rocks in the loose sediment will resettle and block water circulation when the pump is restarted, thus preventing further penetration. In addition, the resettled sediments may prevent or make it difficult to remove the pipe from the hole. No simple and satisfactory prior system has been found whereby one person working alone can bore a deep hole, such as 30 feet or deeper, due to the difficulty for the spudder to handle a probe pipe over 10 feet in length.
SUMMARY OF THE INVENTION
It is an object of the invention, therefore, to provide a water jet sediment probe system whereby one person can bore deep holes exceeding ten feet in depth.
The sediment probe of this invention provides means for making a flexible hose rigid, one portion at a time, so that it can be spudded into the sediment without the need to start with one rigid piece of pipe that is as long as the desired hole depth. A flexible hose is attached to an initial length of pipe which includes the probe tip and a pumping means is provided to pump water under pressure through the flexible hose and out through the probe tip. A series of short rigid rod or pipe sections are attached adjacent to or about the flexible hose at regular intervals as it is spudded into the sediment to provide the required rigidity along the entire length of the probe until the desired hole depth is reached. This system permits one person handling only short sections of rod, pipe, or split pipe to probe or jet-in a hole of indefinite depth without having to raise and use a rigid pipe as long as the desired depth of the hole. The system is operable for use on land or by divers underwater.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an embodiment of the invention using a series of interconnected short sections of rod to stiffen the flexible hose of a water jet sediment probe to a desired depth.
FIG. 2 is another embodiment of the invention using interconnected pipe sections on the flexible hose to provide the desired rigidity.
FIG. 3 shows an embodiment similar to that of FIG. 2, but using split sections of pipe.
FIG. 4 is an illustration showing use of the present invention on shore and underwater.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The embodiment shown in FIG. 1 shows an initial length of rigid metal pipe 10, for example, which can include a jet nozzle at its lower tip 12, if desired. One end of a flexible hose 14, of any desirable length, is connected to the upper end 15 of rigid pipe 10, the other end of hose 14 is connected to a source of water under pressure, such as a pump 17 or 18, as shown in the illustration of FIG. 4. Soil or sediment 19 is liquified at the point of entry, as water is jetted from tip 12 of the probe and it remains liquified (i.e., quick) as long as water is continued to be pumped into the hole from the probe 10.
As probe 10 is spudded into the sediment it is necessary that hose 14 be made rigid in order that the probe can continue to be pushed into the sediment or soil to bore a hole of desired depth. Rigidity is supplied to the desired depth by a series of short rigid metal rods 20 which are connected together in any convenient manner, such as by threaded couplings for example, and to an attachment means 21 at the upper end 15 of probe 10. Clamps or straps 22 fasten the flexible hose 14 to the interconnected rods 20 at regular intervals. This is one manner of making the flexible hose rigid so that it can be spudded into the sediment.
Another means for providing rigidity to flexible hose 14 is illustrated in FIG. 2 where a series of short sections of threaded pipe 30 are slipped onto and stored on the flexible hose. The pipe sections 30 are slid along the hose as needed and screwed into the top of the previous section as the probe end 31 and each added section 30 is spudded into the sediment, until the desired depth is reached.
FIG. 3 shows the addition of sections of split pipe to provide rigidity of flexible hose 14. In this embodiment, each section of pipe consists of two halves, 35 and 36, which are assembled by any suitable means and applied about hose 14. Each assembled section 35, 36 is then connected to the next preceeding section in a similar manner to that shown in FIG. 2 to provide rigidity as the probe is spudded into the sediment to the desired depth.
In each case, retrieval of the probes is accomplished by reversing the process and removing the sections of rod or pipe as the probe is raised from the hole, while continuing to pump water through the system.
With the system described above a hole of indefinite depth can be jetted by one person handling only short (e.g., 5 foot) sections of rod, pipe or split pipe. The system can be used on land or underwater as illustrated by way of example in FIG. 4. As shown in FIG. 4, a single operator 41 on shore is spudding a pipe probe into the sand on the beach. Flex hose 14 is connected from pump 17 to probe pipe 10. The various means for providing rigidity to the flex hose, as already described, will permit the probing of the soil or sediment to a desired depth without the need to use a single rigid pipe, guy lines or guy line tenders. This same system is operable on the seafloor by a diver 45 on the seafloor operating a water jet sediment probe connected by flexible hose to a water pump 18 on a barge, for example.
Any material can be used to provide rigidity to the flexible hose, but where the operator wants to sense what kind of sediment the lower tip of the probe is penetrating by feeling the vibrations transmitted from the pipe lower tip, a stiffener material that is a good conductor of vibrations caused by spudding through the sediment is needed.
This can permit an experienced operator to sense various types of sediment layers, such as sand, clay, gravel or pebbles, rocks, and the like.
Although the jet probe can be used on the seafloor, as discussed and shown in FIG. 4, the logistic problems presented by the pump (and driving engine) and hose become more bothersome. In areas of strong currents (e.g., greater than 1 knot) the forces acting on the hose which must extend from the seafloor to the surface become preventative. Even in relatively quiet current areas (e.g., less than 1/2 knot) 100 feet is the practical limit of the hose for conducting jet probe investigations.
In such underwater operations a battery driven water pump can be used on the seafloor at the end of the flexible hose, and the embodiment shown in FIG. 1 used to probe the seafloor sediment.
Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.
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Various means for providing rigidity to the flexible hose of a water jet iment probe that is used to determine thickness and types of underlying sediment beneath land or seafloor is disclosed. A series of interconnecting rods or pipe sections are used to stiffen a length of flexible hose to a desired probe depth to enable a single operator to bore a hole of indefinite depth without assistance.
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BACKGROUND OF THE INVENTION
The present invention relates to an automatic recorder with a pencil pen having a lead of pencil for recording on a medium by the lead of pencil, and more particularly to a recorder for drafting a drawing by a pen in accordance with a command signal from an external control unit.
Such a recorder is frequently used in connection with a CAD device and it has been widely used because of its capability of rapid drafting of a precise drawing.
The recorder of this type usually uses a drafting ink pen. Since the ink pen is not erasable and it is difficult to correct the drawing drafted by the ink pen, an erasable ink pen has been strongly desired. As a result, the recorder with an erasable pen or pencil pen has been increasingly used.
A prior art pencil pen is explained below. It comprises a lead chuck mechanism for holding and releasing the lead of pencil and a knock mechanism for releasing the lead chuck of the lead chuck mechanism. Because of structural restriction of the recorder, it holds only one lead of pencil. In the recorder with the pencil pen, the lead chuck mechanism is held and released at a fixed position in order to maintain a high drafting quality. If a drive stroke in the hold/release operation is as large as that of a conventional pencil pen, there will be a backlash unless clearances of elements are precisely set, and the drafting quality is lowered. It is difficult to precisely set the clearances of the elements.
In the prior art of pencil pen, since only on pencil lead can be held, it is not possible to automatically and continuously record a long distance of drafting which cannot be drawn without using a plurality of pencil leads.
The following two methods have been proposed to resolve the above problem.
A first method is disclosed in JP-A-61-235199. In this method, a plurality of pencil pens each holding one pencil lead. When the pencil lead of the pencil pen which is currently recording data is exhausted so that the record can no longer be drawn, it is exchanged with one of the pencil pens stored at a predetermined position in the recorder. In this manner, data having long drafting distance can be automatically and continuously recorded.
In this method, however, it is necessary to prepare a plurality of pencil pens of the same type in order to avoid a change of recorded line in the course of recording. As a result, redundant pencil pens are needed.
A second method is disclosed in JP-A-61-235200. In this method, a movable pen block to record data on a medium, a cylindrical multi-lead cartridge held by the pen block for holding a plurality of pencil leads at a constant pitch along a periphery of the pen block, a lead pushing rod held by the pen block for pushing a specific pencil lead selection mechanism for selecting the specific pencil lead from the plurality of pencil leads, and lead pushing rod drive means are used. By systematically operating those elements, data is recorded automatically and continuously.
In the apparatus, however, not only the apparatus is of large scale but various elements are mounted on the pen block and a load to the pen block is high. As a result, the apparatus performance such as recording speed may be affected.
A special apparatusis disclosed in Japanese Utility Model Application Laid-Open No. 56-115,294. The apparatus has a line drafting head including an ejection mechanism for ejecting a redundant pencil lead. Data is recorded by the pencil pen of the line drafting head. When the pencil lead has been exhausted. It is ejected. Because of the provision of the ejection mechanism for the pencil lead, the long period automatic recording can be attained.
In this prior art apparatus, however, since the pencil lead eject mechanism, specifically a solenoid is mounted on the line drafting head which is moved on the medium, the weight of the line drafting head increases. As a result, a drive mechanism for driving the line drafting head becomes of large scale. When the drafting performance, particularly the drafting speed is to be improved, the overall apparatus must be constructed rigidly.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a recorder with a pencil pen which holds a plurality of pencil leads and automatically drives and ejects the pencil leads.
It is another object of the present invention to provide a recorder having a pencil lead holder for ejecting a residual pencil lead and a residual pencil lead processing unit.
It is other object of the present invention to provide a recorder with a pencil pen which can record for a long time by providing a pencil lead feed and eject mechanism.
It is a further object of the present invention to provide a recorder with a pencil pen which attains continuous recording by only one pencil pen.
In order to achieve the above objects, in accordance with the present invention, means for holding a plurality of pencil leads and feeding and ejecting the pencil leads one by one is provided. More specifically, means for holding and releasing a chuck of the pencil pen and means for vertically moving a pencil lead displacing mechanism are provided and those means are alternately operated.
In an initial state, a plurality of pencil leads are held in a lead tank of a pencil pen. One lead (first lead) is taken from the lead tank into a lead path of the pencil pen. The lead chuck mechanism is now released to hold the pencil lead, and the pencil lead displacing mechanism is actuated to drive the pencil lead for recording. When the first lead has been exhausted and released from the pencil lead chuck mechanism, recording is no longer carried out by the first lead. At this moment, the second pencil lead has entered into the lead path and held by the lead chuck mechanism. By vertically driving the pencil lead displacing mechanism reciprocally, the first lead whose trailing end abuts against a leading end of the second lead is driven by a distance of one vertical drive. Thus, there is a gap of one vertical drive between the trailing and of the first lead and the leading end of the second lead. The lead chuck mechanism is then released once to drive the second lead so that the leading end thereof abuts against the trailing end of the first lead. By alternately actuating the chuck mechanism and the pencil lead displacing mechanism, the first lead which can no longer record is removed.
In accordance with the present invention, the problems encountered in the prior art apparatus are resolved and the following advantages are offered. Namely, since the lead feed and eject mechanism for feeding and ejecting the pencil lead in provided, long time recording can be attained. Since the lead eject holder to remove the residual lead and the residual lead processing unit for processing the residual lead are provided, recording by the pencil pen can be efficiently done.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a side sectional view of a known pencil pen used in the recorder and recording method of the present invention;
FIGS. 2A to 2F show a time-sequential relationship between a pencil lead and a record panel in a recording process by a known recorder with the pencil pen shown in FIG. 1;
FIGS. 3 and 4 show a first embodiment of the recorder and recording method with the pencil pen of the present invention, in which FIG. 3 shows a top view of an overall construction of the apparatus as viewed from the record panel, and FIG. 4 shows a side view of a pen block which serves as lead feed and eject means and a cooperating unit;
FIG. 5 shows a side view of a pen block which serves as the lead feed and eject means and a cooperating unit in second embodiment;
FIGS. 6 and 7 show a third embodiment in which FIG. 6 shows a top view of an overall construction of the apparatus as viewed from the record panel, and FIG. 7 shows a side view of a pen block and lead feed and eject means and a cooperating unit;
FIGS. 8A, 8B, 9 and 10 show a fourth embodiment, in which FIG. 8A is a conceptual view showing an arrangement of mechanical units of the embodiment, FIG. 8B shows an electrical block diagram, FIG. 9 shows a perspective view of a lead feed and eject unit and a cooperating unit, and FIG. 10 shows a flow chart for explaining an operation of the embodiment; and
FIGS. 11A, 11B and 12 show a fifth embodiment, in which FIG. 11A shows a conceptual view of arrangement of mechanical units in the embodiment, FIG. 11B shows a block diagram of an electrical circuit, and FIG. 12 shows a side view of a lead feed and eject unit, a pen holder and a cooperating unit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Prior to the explanation of the embodiments of the recorder with the pencil pen which embodies the concept of the present invention, construction and function of a pencil pen used in a prior art recorder are explained with reference to FIGS. 1 and 2A to 2F.
In FIG. 1, numeral 11 denotes a knock mechanism, numeral 12 denotes a lead chuck mechanism, numeral 13 denotes a pencil lead displacement mechanism, and numeral 14 denotes a case.
The knock mechanism 11 has a lead tank 111 for holding a plurality of pencil leads 15 and a knock spring 112 which couples to a lead chuck mechanism 12 to be explained later.
The lead chuck mechanism 12 has a split chuck member 122, a ball 123 attached to the chuck member 122, a chuck case 121 and two chuck springs 124 and 125. Numeral 126 denotes a shock absorbing spring.
The pencil lead displacement mechanism 13 is formed at an end of the pencil pen 1, and a rubber ring 131 for holding the pencil lead with an appropriate friction is provided at a predetermined position in the pencil lead displacement mechanism.
An inner case 141 positions the lead chuck mechanism 12 at a predetermined position in the pencil pen 1 and holds the pencil lead displacement mechanism 13, which is vertically slidably supported and coupled by a coupling spring 132.
The function is now explained.
The plurality of pencil leads 15 held in the lead tank 111 are taken into a lead path, one at a time, by a funnel-shaped member 127 formed above the lead chuck mechanism 12. The pencil lead 15 taken into the lead path is referred to as a first pencil lead 15a. By vertically moving the knock mechanism 11 one or more times, that is, releasing and holding the chuck member 122, the first pencil lead 15a is held by the chuck member 122 of the lead chuck mechanism 12. The leading end of the first pencil lead 15a normally abuts against the rubber ring 131 of the pencil lead displacement mechanism 13. By vertically moving the pencil lead displacement mechanism 13, the first pencil lead 15a is gradually driven out. More specifically, when the chuck mechanism of the pencil pen holds the pencil lead, it has a relatively weak holding force in a drive-out direction of the pencil lead and a very strong holding force in a drive-back direction of the pencil lead. Accordingly, when the pencil lead displacement mechanism 13 is vertically moved, the first pencil lead 15a is not displaced because it is held by the chuck member 122, and the pencil lead displacement mechanism 13 changes the position relative to the first pencil lead 15a. When the pencil lead displacement mechanism 13 returns to the initial position, the first pencil lead 15a is driven out by a friction of the rubber ring 131 by a distance of vertical stroke.
When the first pencil lead 15a goes out of the leading end of the pencil pen 1, it can record data. As the pencil lead, 15a is consumed as the recording is done and the tail end of the pencil leads 15a leaves the lead chuck mechanism 12, the recording is no longer carried out. In this case, the first pencil lead 15a must be removed.
In the lead chuck mechanism 12 of the pencil pen 1 of the prior art apparatus, since the hold/release operation is carried out at a fixed position in order to maintain a high record quality, the lead chuck mechanism 12 itself has no function to drive out the pencil lead 15. Accordingly, when the first pencil lead 15a has been consumed and left the lead chuck mechanism and the second pencil lead 15b follows and the knock mechanism 11 is operated while the second pencil leads 15b is held by the lead chuck mechanism 12, the first pencil lead 15a cannot be removed. The first pencil lead 15a is held by the rubber ring 131 of the pencil lead displacement mechanism 13 by a predetermined frictional force.
It is now assumed that the first pencil lead 15a and the second pencil lead 15b are in a condition as shown in FIG. 1, that is, the first pencil lead 15a has left the lead chuck mechanism 12 and the second pencil lead 15b contacts to the trailing edge of the first pencil lead 15a. The pencil lead displacement mechanism 13 is pushed up by a predetermined amount against the coupling spring 132. As the pencil lead displacement mechanism 13 is raised, the first pencil lead 15a held by the frictional force of the rubber ring 131 tends to be raised by a predetermined amount. However, since the second pencil lead 15b which contacts to the trailing edge of the first pencil lead 15a is held by the lead chuck mechanism 12, the first pencil lead 15a is not raised but stays at the current position. As a result, the first pencil lead 15a is advanced relative to the pencil lead displacement mechanism 13. When the pencil lead displacement mechanism 13 is then returned to the initial position, a gap of a predetermined amount (corresponding to the rise of the pencil lead displacement mechanism 13) is created between the trailing edge of the first pencil lead 15a and the second pencil lead 15b. The knock mechanism 11 is then depressed. The lead chuck mechanism 12 is released and the second pencil lead 15b drops by a gravity to contact to the trailing edge of the first pencil lead 15a. By alternately repeating the above two operations, that is, pushing up of the pencil lead displacement mechanism 13 and the depression of the knock mechanism 11, the first pencil lead 15a can be removed.
FIGS. 2A to 2F show recording conditions when the pencil pen 1 is mounted on the recorder for recording. In FIGS. 2A to 2F, the pencil pen 1 shown in FIG. 1 is shown in a simplified form. Numeral 719 denotes a stopper provided in an automatic drafting machine, and numeral 73 denotes a record surface.
In FIGS. 2A to 2F, in an initial condition, the pencil pen 1 is in an up position, that is, the pencil lead displacement mechanism 13 is not pushed up (FIG. 2A), and the pencil lead 15 is not contacted to the record surface 73.
In a normal state, the pencil pen 1 is in an up state as shown in FIG. 2A. When the pencil pen 1 is moved down by a pen move-down command, the pencil lead displacement mechanism 13 abuts against the stopper 719 (FIG. 2B). As the pencil pen 1 is further moved down, the pencil lead displacement mechanism 13 is in the push-up state as shown in FIG. 1 so that the pencil lead 15 is driven out. As the pencil pen 1 is further moved down, the leading and of the pencil lead 15 abuts against the record panel 73 (FIG. 2C). Then, record is made on a record sheet (not shown) mounted on the record panel 73. As the pencil lead 15 is abraded during the recording, the pencil pen 1 is moved down as shown in FIG. 2D by a draw pressure force (downward biasing force) of an actuator (not shown) of the pencil pen 1 so that the recording is continued.
At the end of the recording, when the pencil pen 1 is moved up, the pencil lead displacement mechanism 13 is gradually driven out as shown in FIG. 2E. Referring to FIG. 1, the pencil lead displacement mechanism 13 advances from the position embedded into the pencil pen 1. At the end of the moving-up of FIG. 2F, the pencil lead displacement mechanism 13 is moved downward to the initial position and and the pencil lead 15 for the next recording is driven out.
Referring to FIGS. 3 and 4, a first embodiment of the present invention is explained.
In FIG. 3, numeral 7 denotes a recorder, numeral 71 denotes a pen block or pen carriage, numeral 72 denotes a Y-bar, numeral 73 denotes a record panel, and numeral 75 denotes a container pen holder. The pen block 71 is supported by the Y-bar 72 and movable on the record panel 73. A record pen such as a pencil pen 1 is held by the pen block 71, and records a data signal supplied from a CPU (not shown) at coordinates on the record panel designated by the data signal under the control of a control signal a plurality of record pens are stored in the container pen holder 75. When a lead of a current pencil pen has been consumed, it is exchanged with a spare one. Alternatively, other type of record pen than the currently used pencil pen, that is, a pencil pen of different color or a ball-point pen may be used as the record pen. A knock plate 781 is formed on a frame 78 of the container pen holder 751 to actuate the knock mechanism 11 of the pencil pen 1.
FIG. 4 shows major portions of the first embodiment. The function of the knock plate 781 to the pencil pen 1 is first explained and then the operation of the embodiment is explained.
The pen block 71 comprises a base 711, an actuator 712, a pen arm 713, a pen holder 714, a slide bearing 715, a bearing 716 and the stopper 719 shown in FIGS. 2A to 2F. The stopper 719 also functions as a second engagement member 652 which abuts against the pencil lead displacement mechanism 13 to move it up and down. The pen holder 714 holds the pencil pen 1 and is vertically driven through the pen arm 713 in response to energization and deenergization of an electro-mechanical actuator 712 having a solenoid. The second engagement member 719 provided below the pen block 71 abuts against the pencil lead displacement mechanism 13 of the pencil pen 1 to vertically drive the pencil lead displacement mechanism 13 as the pen holder 714 is vertically driven.
Let us assume that the pencil lead 15 of the pencil pen 1 is to be removed. The pen block 71 supported by the Y-bar 72 moves the pencil pen 1 to a predetermined position on the recorder by a data signal from the CPU, and causes the knock mechanism of the pencil pen 1 to abut against the first engagement member 651 formed on the knock plate 781. In the present embodiment, when the pencil pen 1 is to be positioned to a predetermined position by the data signal, an input signal is applied to the actuator 712 corresponding to a signal intermediate of actuation signal and deactuation signal so that the pencil pen 1 is held at an up position and a down position. Accordingly, when the pencil pen 1 is to be moved, no control signal for operation is applied to the knock mechanism of the pencil pen 1 and the pencil lead displacement mechanism 13. As the pencil pen 1 is position to the predetermined position, a control signal is applied to the electro-mechanical actuator 712 to first move down the pencil pen 1 and the move it up. This corresponds to the vertical movement of the pencil lead displacement mechanism 13 shown in FIG. 1 and the vertical movement of the knock mechanism 11, that is, holding and releasing of the lead chuck mechanism 12. By alternately repeating those two vertical movements, unnecessary pencil lead 15 can be removed from the pencil pen 1 held by the pen holder 714. A step 731 of FIG. 4 serves to drop the unnecessary pencil lead 15 ejected from the pencil pen 1.
Referring to FIG. 5, a second embodiment of the present invention is explained.
A recorder of the second embodiment shown in FIG. 5 is substantially identical in construction to the first embodiment of FIG. 4, except that it is a knock plate 238 mounted on a base 711 of the pen block 23 that a first engagement member 651 abutting against the knock mechanism 11 of the pencil pen 1 is mounted on unlike the first embodiment in which it is mounted on the knock plate mounted on the frame of the recorder. In the second embodiment, the pen up-position for normal recording operation of the recorder is lower than a highest possible position of the pencil pen. The knock mechanism 11 of the pencil pen 1 is not pushed down by the knock plate 238 by the move-up operation of the pencil pen in the normal recording.
In the second embodiment, the operation to remove the unnecessary pencil lead is essentially identical to that of FIG. 4 and the explanation thereof is omitted.
A third embodiment of the recorder of the present embodiment is shown in FIGS. 6 and 7.
In FIG. 6, numeral 7 denotes a recorder, numeral 71 denotes a pen block, numeral 72 denotes a Y-bar, numeral 73 denotes a record panel, numeral 66 denotes a lead feed/eject holder which is one component of a lead feed/eject unit 6, and numeral 75 denotes a container pen holder formed on one side edge of the record panel. The pen block 71 is supported by the Y-bar 72 and movable on the record panel 73 in X and Y directions is accordance with a data signal from a CPU (not shown). The movable pen holder 711 of the pen block 71 holds the pencil pen 1 and it contacts or moves away from the record panel in accordance with the control signal from the CPU to record data, as is done in the previous embodiments. The container pen holder 75 stores a plurality of record pens of the same or different types and they are exchangeably used as required. The lead feed/eject holder 66 is formed adjacently to the storage pen holder 75. By moving the pencil pen 1 in a direction a, it may be held by one of the lead feed/eject holders 66. By moving the pencil pen 1 in a direction b, the pencil pen 1 which is held by the lead feed/eject holder 66 can be taken out. By a relative movement between the lead feed/eject holder 66 and the movable pen holder 711, the pencil pen 1 is exchanged between the lead feed/eject holder 66 and the movable pen holder 711. This operation is similar to a conventional pen exchange operation and may be carried out by using technical means disclosed in JP-B-59-400(corresponding to U.S. Pat. No. 4,401,996).
FIG. 7 illustrates or operation of the lead feed/eject holder 6 and shows a side view.
The lead feed/eject holder 6 shown in FIG. 7 has a lead eject holder base 61. A holder frame 611 is mounted on the base 61 and a right portion thereof forms a lead feed/eject holder 66. A solenoid 64 is mounted at a predetermined position on the frame 611 and a movable member 65 couples to an action shaft 641 of the solenoid 64. The movable member 65 is supported such that it is vertically movable against a spring 654 along a slide shaft 653 mounted on the frame 611. A push-down member 656 is integrally formed with a lowermost portion of the movable member 65, and it engages with a push-down rod 712 formed on the pen block 71 to push down the movable member 65. The movable member 65 has first engagement member 651 and second engagement member 652 fixed at top and bottom thereof. When the pencil pen 1 is held by the pen holder 66 of the frame 611, the first engagement member 651 functions to release the knock mechanism 12, and the second engagement member 652 abuts against the pencil lead displacement mechanism 13 to push it up.
In the present apparatus, a residual lead processing unit 69 is provided at the bottom of the lead feed/eject unit 6. The residual lead processing unit 69 includes a residual lead receptacle 691 which is removable from the apparatus, a sensor mounting plate 671 mounted to the lead eject holder base 61 and a positioning member 692 for positioning a sensor 67 and the residual lead receptacle 691. Instead of using the residual lead receptacle 691 which is removable from the apparatus, one end of the residual lead receptacle 691 may be rotatably engaged to the apparatus so that it is rotated by 180 degrees to eject the residual lead from the recorder.
As shown in FIG. 7, as the pencil pen 1 held by the movable pen holder 711 of the pen block 71 is consumed so that it can no longer create sharp record, the lead ejection operation is started by a command signal from an internal electric circuit (not shown) of the recorder. The pen block 71 is moved in a direction a shown in FIG. 6 to hold the pencil pen 1 by one pen holder 66 of the lead feed/eject unit 6. A push-down member 656 formed on a movable member 65 of the lead feed/eject unit 6 is pushed down by a push-down rod 712 formed in the pen block 71. When the pen block 71 is retracted, the second engagement member 652 abuts against the pencil lead displacement mechanism 13 of the pencil pen 1 so that it pushes up the pencil lead displacement mechanism 13 by an upward biasing force of the spring 654. The first engagement member 651 is now positioned at a position which permits abutment against the flange 113 of the knock mechanism 11 of the pencil pen 1.
Under this condition, the solenoid 64 is energized and deenergized a predetermined number of times. Thus, the movable member 65 is vertically displaced the predetermined number of times. Thus, as explained above in connection with FIG. 1, the residual lead of the pencil pen 1 is removed by the coaction of the flange 113 of the pencil pen 1 and the first engagement member 651 and the coaction of the pencil lead displacement mechanism 113 and the second engagement member 652.
As the residual lead is ejected from the pencil pen 1 in this manner, the residual lead passes through a residual lead drop hole 693 and is detected by the sensor 67. The detection signal is sent to the internal electric circuit and the lead ejection operation is terminated.
As seen from FIG. 1 which shows a known pencil pen, the next pencil lead is now drive out to the leading edge of the pencil pen 1. Accordingly, the record operation can be immediately started.
The residual lead is stored in the residual lead receptacle.
A fourth embodiment of the recorder of the present invention is now explained with reference to FIGS. 8A, 8B, 9 and 10.
FIG. 8A shows a mechanical system of the present embodiment and FIG. 8B shows an electrical system thereof. As shown in FIGS. 8A and 8B, in the present embodiment of the recorder, a record medium 45 is moved in an X-axis direction and a carriage 2 is moved in a Y-axis direction to draw a desired drawing. The record medium 45 is moved by a drive roller 36 and a pinch roller (not shown) and controlled by a CPU through a sheet driver 34 and a sheet drive motor 35. The carriage 2 is controlled by the CPU through, a pen driver 30 and a pen drive motor 31. A turret 5 for holding a plurality of record pens is provided at a predetermined position so that it cooperates with the movable pen holder of the carriage 2 to permit exchange of the record pens. The turret 5 is rotated to allow take-out of a desired one of the plurality of record pen. It is also controlled by the CPU through a, turret driver 38 and a turret drive motor 39. Such a pen exchange unit is disclosed in Japanese Utility Model Application Laid-Open No. 58-154,422.
The recorder is provided with a lead feed/eject unit 6 to permit the use of the pencil pen 1 as shown in FIG. 1. The lead feed/eject unit 6 of the present embodiment cooperates with the turret 5. The lead feed/eject unit 6 is controlled by the CPU through a lead feed/eject unit driver 40 and a lead feed/eject unit motor 41 so that it cooperates with the turret 5 to move relative to the turret 5 to take in the pencil pen 1 whose lead is to be fed or ejected. This operation may also use the same technique as that of the pen exchange operation described above.
Referring to FIG. 9, the lead feed/eject unit 6 is explained.
The lead feed/eject unit 6 shown in FIG. 9 is essentially identical to that shown in FIG. 7.
The pencil pen 1 whose lead is to be fed or ejected is taken from the turret 5 into the pen holder 66 of the lead feed/eject unit 6, and the movable member 65 having the pen holder 66 is vertically moved by the solenoid 64 of the lead feed/eject unit 6. Since the pencil pen 1 is vertically moved by the vertically moving pen holder 66, the knock mechanism 11 and the pencil lead displacement mechanism 13 abut against the first engagement member 651 and the second engagement member 652, respectively, fixed at the predetermined positions on the lead feed/eject unit 6. As a result, the hold/release operation of the lead chuck mechanism 12 through the knock mechanism 11 and the vertical movement of the pencil lead displacement mechanism 13 are alternately carried out.
The lead feed/eject unit 6 has a first slide member 631 and a second slide member 632 which slide along a rail 62 mounted on a chassis 61 of the recorder. The second slide member 632 is arranged above the rail 62, and a plurality of rollers (not shown) mounted on the second slide member 632 slide on a groove formed on a top surface of the rail 62. The first slide member 631 has an upper portion thereof coupled to the second slide member 632 and is arranged along a side wall of the rail 62. An actuator 64 is mounted at a predetermined position on the first slide member 631 and an action axis 641 thereof is coupled to a vertically movable member 65. A pen holder 66 for holding the pencil pen 1 whose lead is to be fed or ejected is provided at a right end of the vertically movable member 65. Accordingly, the pencil pen 1 whose lead is to be fed or ejected is vertically moved through the vertically movable member 65 and the pen holder 66 by energizing the actuator 64. The vertically movable member 65 and the second slide member 632 are coupled by spring 6654. Thus, when the actuator 64 is energized, the vertically movable member 65 and hence the pencil pen 1 are moved downward, and when the actuator 64 is deenergized, the vertically movable member 65 and hence the pencil pen 1 are moved upward by the spring 654. The vertically movable member 65 and the second slide member 632 are coupled by another spring 633. The spring 733 causes the left end of the vertically movable member 65 to abut against the roller of the second slide member 632 to prevent rotation of the vertically movable member 65 when it is vertically moved.
A second engagement member 652 is provided on a bottom surface of a projection (an abutment of a slide shaft of the vertically movable member 65) at the lower portion of the first slide member 631 and it abuts against the pencil lead displacement mechanism 13 of the pencil pen 1. A first engagement member 651 is provided at a top right portion of the second slide member 632. It is abuttable against a flange 113 of the knock mechanism 11 of the pencil pen 1.
A sensor mounting plate 671 is provided at a right bottom portion of the first slide member 631 to detect an ejected pencil lead or namely driven pencil lead. The lead feed/eject unit 6 is slid by a pulse motor 41 through a transmission member (not shown) provided on the opposite side of the chassis 61.
If the CPU of the recorder detects absence of lead for the pencil pen 1 under recording, the drafting cannot be continued and the CPU issues a command signal to the pen drive 30 and the turret driver 38 to store the pencil pen 1 which cannot record, into the turret 5. Another record pen held in the turret 5 may be taken in to draft the same or other drawing.
The pencil pen 1 which cannot record and is held in the turret 5 is removed into the pen holder 66 of the lead feed/eject unit 6 by the turret driver 38 and the lead feed/eject unit driver 40 in response to the command signal from the CPU. The hold operation is carried out by the lead feed/eject unit 6 which cooperate with the turret 5 to move itself by a predetermined distance rightward in FIG. 9 by the pulse motor 41. The turret 5 has a hold collar 51 comprising a plurality of recesses for a plural of pencil pens, respectively, at the upper portion thereof, and also has a plurality of pen cap holding members 52 at the lower portion. Each of the pen cap holding members 52 has a tapered plane and a flat plane supporting a pen cap adaptable to receive the tip of a pencil pen. In operation, the tapered plane 521 of the pen cap holding member 52 is pressed down by a member (not shown) which acts in accordance with the movement of the lead feed/eject unit 6.
When the lead feed/eject unit 6 which has take the unrecordable pencil pen 1 therein retracts to a position shown in FIG. 9, an electro-mechanical actuator (for example, solenoid) 64 is energized and deenergized by the actuator driver 43 in response to the command signal from the CPU so that the lead is fed or ejected. The ejected pencil lead is detected by the lead sensor 67. The sensor 67 also detects whether a new pencil lead is driven out. The sensor signal is sent to a lead detection logic circuit 4 through an amplifier 44. The circuit 4 display "no lead" or "end of lead feed" on display means (not shown).
As the new pencil lead is driven out, the lead feed/eject unit 6 retracts by a predetermined distance to engage with a lead push-up member 683 which is biased upward by a spring 684. One end of the lead push-up member 683 is rotatably supported by the chassis 61 by a screw 681. A bearing 682 is mounted at a top of the lead push-up member 683 and slides on the bottom surface of the first slide member 631 of the lead feed/eject unit 6. The bottom surface is tapered at a position close to the lead feed/eject pen holder 66. Accordingly, when the lead feed/eject unit 6 retracts by the predetermined distance, the lead push-up member 683 is pushed up by the biasing force of the spring 684 to push back the lead of the pencil pen 1 which has been driven out, into the pencil pen 1. The solenoid 64 of the lead feed/eject unit 6 is now deenergized and the lead chuck mechanism 12 of the pencil pen 1 is released. Thus, the pencil pen can be readily pushed back into the pencil pen 1 to adjust the lead length. FIG. 10 shows an operational flow diagram for explaining the series of operations described above.
In an step 1, the non-recordable pencil pen 1 whose lead has been consumed is held in the pen holder 66 of the lead feed/eject unit 6 under the control of the CPU 22.
Then, the lead feed/eject unit 6 is moved backward or leftward in FIG. 10 by the pulse motor 41 under the control of the CPU 22 as shown in FIG. 9 so that it is positioned at the lead feed/eject position (step 2).
Under this condition, the CPU 22 issues a start signal to the logic circuit which includes the lead detection logic circuit 42 shown in FIG. 8B to shift the control of operation to the logic circuit. In the present embodiment, the CPU 22 starts another operation from this time point (step 3).
The step 4 et seq are carried out by commands from the logic circuit. In the step 4, the lead feed/eject actuator (solenoid) 64 shown in FIG. 9 is energized once, that is, the lead chuck mechanism 12 (see FIG. 1) of the pencil pen 1 held by the lead feed/eject holder 66 is held and released once and the pencil lead displacement mechanism 13 is vertically moved once.
In a step 5, the lead sensor 67 shown in FIG. 9 starts to detect whether unnecessary residual lead has been ejected or not. In the step 5, if the ejection of lead is not detected, the process proceeds to a step 12. In the step 12, whether the solenoid 64 has been energized N (predetermined number) times or not. If N times is not reached, the process returns to the step 4.
If N times is reached that is, if the ejection of lead is not detected after N times of energization of the solenoid 64, the process proceeds to a step 13 to set an error signal.
In the step 5, if the ejection of unnecessary residual lead is detected, the process proceeds to a step 6 where the solenoid 64 is energized once. In a step 7, the lead sensor 67 detects whether a new pencil lead has been driven out in the step 6 or not. If the drive-out of the new lead pencil is not detected in the step 7, the process proceeds to a step 8 where whether the solenoid 64 has been energized M (predetermined number which may be equal to N) times or not is checked. If M times is not reached, the process returns to the step 6. When the new pencil lead is not driven out after M times of energization, the process proceeds to a step 13 to set an empty signal.
In the step 7, if the lead sensor 67 detects the drive-out of the new pencil lead, the process proceeds to a step 9. In the step 9, a ready signal is set to inform to the CPU 22 that the lead feed/eject operation by the logic circuit which controls the lead feed/eject operation has been completed. The subsequent operation is carried out under the control of the CPU 22.
In a step 10, the lead feed/eject unit 6 is moved backward or leftward in FIG. 9 by the predetermined distance by a signal from the CPU 22 and the driven-out pencil lead is adjusted to a predetermined length by the lead push-up member 683 as shown in FIG. 9.
In a step 11, the pencil pen 1 having the lead thereof fed is held by the pen carriage 2 through the turret 5 so that the recorder is ready for recording.
Finally, a fifth embodiment of the recorder of the present invention is explained with reference to FIGS. 11A, 11B and 12.
The fifth embodiment shown in FIGS. 11A, 11B and 12 is substantially identical to the fourth embodiment shown in FIGS. 8A, 8B, 9 and 10 a record medium 45 moves in an X-axis direction and a carriage 2 for holding a pencil pen 1 moves in a Y-axis direction. It differs from the previous embodiment in that the lead feed/eject operation is attained without the electro-mechanical actuator 64 of the lead feed/eject unit 6. Only the difference is explained below with reference to FIG. 12.
A pen holder 66 of the lead feed/eject unit 6 is mounted on a slide member 63 which is slid along a rail 62 by a pulse motor (not shown). The slide member 63 has a first engagement member 651 mode of a lever member which engages with a flange (not shown) of a knock mechanism 11 when the pencil pen 1 is held by the pen holder 66. The first engagement member 651 has a raised area 651q behind the center thereof, and a rear end 651p thereof is rotatably held by the slide member 63. In the rear end 618, the first engagement member 651 is always biased upward by a coiled spring (not shown). A bearing 653 fixed to a chassis (not shown) engages to the raised area 651q of the first engagement member 651. Accordingly, as the slide member 63 moves back and forth to engage and disengage the raised area 651q and the bearing 653, the knock mechanism 11 of the pencil pen 1 is vertically moved or the lead chuck mechanism 12 is held and released.
On the other hand, a lead push plate 68 having a second engagement member 652 which abuts against a pencil lead displacement mechanism 13 of the pencil pen 1 is rotatably mounted on the chassis by a screw 681, and it is biased upward by a spring 684. One end of the spring 684 is fixed to the lead push plate 68 and the other end is fixed to the chassis.
A bearing 682 is attached to the lead push plate 68 along a lower side of the slide member 63. A projection 631t and a recess 631s are formed in the lower side of the slide member 63. The rotation position of the lead push plate 68 is changed by the engagement of the bearing 682 with the projection 631t and the recess 631s.
A lead push-up member 683 is formed at a front end of the lead push plate 8.
When the lead feed/eject unit 6 is at the position shown in FIG. 12, the second engagement member 52 of the lead push plate 68 pushes up the pencil lead displacement mechanism 13 of the pencil pen 1 and the first engagement member 651 does not contact with the flange of the pencil pen.
When the lead feed/eject unit 6 moves forward or rightward and the projection 631t on the lower side of the slide member 631 comes above the bearing 682 of the lead push plate 68, that is, when the projection 631t on the lower side of the slide member 63 comes from a chain line position (e) to a chain line position (d), the lead push plate 8 is pushed down below the projection 631t so that the pencil lead displacement mechanism 13 of the pencil pen 1 is free and moves down to the low end position the first engagement member 651 above the pencil pen 1 has the raised area 651q thereof pushed down by the bearing fixed to the chassis. Consequently, the knock mechanism 11 of the pencil pen 1 is pushed down and the lead chuck mechanism 12 is released.
In the present embodiment, the lead feed/eject unit 6 moves between the positions (e) and (d) along the rail 62 under the control of the CPU 22 so that the lead chuck mechanism 12 of the pencil pen 1 and the pencil lead displacement mechanism 13 are alternately operated.
The unnecessary residual lead ejected through the above operations is detected by the lead sensor 67 provided at the predetermined position. The drive-out of the new pencil lead is also detected by the lead sensor 67.
In the present embodiment, the lead sensor 67 is mounted at the predetermined position on the lead push-up member, although it may be mounted on the chassis. The lead sensor 67 must be arranged directly below the pencil pen 1 when the ejected residual lead drops or the new pencil lead is driven out.
As the new pencil lead is driven out, the lead feed/eject unit 6 temporarily retracts to engage the bearing 682 of the lead push plate 68 with the recess 631s of the slide member 631. Under this condition, the lead push-up member 683 of the lead push plate 68 abuts against the newly driven-out pencil lead of the pencil pen 1 to adjust the drive-out length. Since the first engagement member 651 has the raised area 651q thereof engaged with the fixed bearing 653 and is pushed down, the lead chuck mechanism 12 is released. Accordingly, it does not impede the adjustment of the driven-out pencil lead. In the present embodiment, since a solenoid for the lead feed/eject operation is not used, an electrical circuit configuration is one shown in FIG. 11B. The lead feed/eject unit driven 40 and the lead detection logic circuit 42 cooperate under the control of the CPU 22.
Here, a chain line (P) shows a moving, pass of the pencil pen 1 taken out from a take-in position thereof in the turret 5.
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A recorder with a pencil pen which contains a plurality of pencil leads therein comprises means for causing a lead chuck mechanism of the pencil lead to hold and release the pencil lead and means for vertically moving a pencil lead displacement mechanism of the pencil pen. Those means are alternately activated by lead feed/eject means to eject a consumed unnecessary pencil lead and drive out a new pencil lead and hold it at a recording position. Since the pencil leads can be automatically ejected and driven out, a recording efficiency is improved and long period continuous recording is attained with a single pencil pen. A lead feed/eject holder is provided to eject a residual lead of the pencil pen, and a processing unit for processing the ejected residual lead is provided. Thus, the recording efficiency is further improved.
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This is a continuation of application Ser. No. 08/237,507, filed May 3, 1994, now U.S. Pat. No. 5,481,439.
BACKGROUND OF THE INVENTION
The present invention relates to an automatic lighting system in which a lighting work in photographing in a studio is effectively and promptly performed in such a manner that a present lighting technique of professional photographers is made stored in a computer, whereby a high-quality photograph in conformity to the lighting usually performed by professional photographers can be obtained; and to an automatic lighting equipment for performing that system.
What most affects photographing, and particularly the quality and work-hours of commercial photographing is lighting work. The lighting work generally has been such that a photographer has moved back/forth and right/left a plurality of lights to find a lighting condition which he has considered most suitable and took a picture at the position satisfying the condition. However, the work to find the lighting position which he has considered most suitable has been not easy and conventionally taken one to two hours.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an automatic lighting system which firstly, in a lighting work in photographing, makes it possible for even those who have not a professional technique to produce very easily a lighting condition limitlessly close to a lighting technique of professional photographers, and which secondly, makes it possible to shorten significantly photographing time and to provide a uniform lighting without developing variation by individual photograph works; and to provide an automatic lighting equipment employing that system.
The lighting equipment comprises a frame; a top lighting fixture which is provided on or separately from the frame, slidable right and left along a circular arc-shaped guide rail movable back and forth of the frame, and swivelable back and forth on the circular arc-shaped guide rail. Lower lighting fixtures are provided as a pair on both sides of the frame, slidable up and down along circular arc-shaped holding fixtures with the center of the frame taken as their center, and rotatable within a range of -10° to +35° when the range is straddled by a center line toward the center of the frame. A hemispherical sensor is provided at the center of the frame, thereby allowing the automatic check of luminous energy.
The circular arc-shaped holding fixtures comprise in combination a link mechanism and a telescopic mechanism, or in combination telescopic mechanisms crossing to each other.
Using such equipment, a mimic subject having a basic size and configuration frequently used in photographing is placed on the frame; its lighting position and luminous energy are adjusted by a photographer having an expertise to obtain an ideal condition; said condition is converted by a position reading device and a photo sensor to an electric signal; an luminous energy to which various portions of the subject are subjected is measured; then, these conditions are stored in a computer. In actual photographing, data are thus automatically selected which are closest to preprogrammed sample data, thereby allowing the lighting work according to said data to be automatically performed.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a front view of an automatic lighting equipment.
FIG. 2 is a right side view of FIG. 1.
FIG. 3 is a plan view of the embodiment of the present invention of FIG. 1 omitting lighting fixtures 2 and 3 and further showing back paper supporting pillars 12.
FIG. 4 shows a hemispherical sensor is which (a) is a plan view and (b) is a front view.
FIG. 5 is a block diagram of a system.
FIG. 6 shows another example of a holding mechanism instead of a circular arc-shaped holding mechanism.
FIG. 7 shows still another example of a holding mechanism instead of a circular arc-shaped holding mechanism.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the drawings, a lighting equipment of the present invention will be explained. On the equipment, there are provided three lighting fixtures. That is, one top lighting fixture 1 is provided on the upper side of a frame 4, and two lower lighting fixtures 2 and 3 provided on the both sides of the frame 4. These lighting fixtures are used to irradiate light to a subject (not shown) such as an object placed on the top side 5 of the frame 4 from three sides, that is, from upper side and both sides, so that the subject can be photographed at an optimum position. The frame 4 is allowed to have a width and a strength by which an object having large dimensions, for example, about 500 mm wide, 500 mm long and 500 mm high can be placed on the frame.
The present equipment, in which a subject is placed on the photographing device to photograph as described above, uses computer software as described below to allow high-accuracy photographing. That is, with a mimic subject having a basic size and configuration such as that relatively frequently used in photographing placed on the frame, its lighting (light position and luminous energy) is adjusted by a photographer having expertise to obtain an ideal condition. That condition is converted by a position reading device and a photo sensor to an electric signal, a luminous energy to which various portions of the subject are subjected is measured, and these conditions are stored in computer memory. The same work is repeated by changing the size and configuration of the mimic subject, and then these conditions obtained are also stored as data.
In actual photographing, the size and configuration of the subject are thus automatically selected from that closest to preprogrammed sample data, whereby the lighting work (to control light position and brightness) according to said data is automatically performed. It is more preferable that a control box is placed close to the photographer, which has a function capable of finely adjusting respective brightnesses of three lighting fixtures. Further, the present equipment is adapted for manual operation where uniform photographing is preferably avoided because of the nature of the subject and the like. There is provided a function in which the operation of a preset switch causes the adjustment to be returned to automatic mode.
With reference to FIG. 2 and following drawings, the present equipment will be explained in detail. As shown in FIG. 2, there are provided one top lighting fixture 1 and two lower lighting fixtures 2 and 3 which are a pair of right and left fixtures, thus three fixtures in total. The top lighting fixture 1 is supported by the arc-shaped guide rail 6 with a radius of about 1600 mm which straddles between pillars 6a and 6a erectly provided on both sides of the frame 4, and movable about 1000 mm right and left from the center on the arc-shaped guide rail 6, as shown in FIG. 1. As shown in FIG. 3, the fixture 1 is slidable about 500 mm forth and about 400 mm back of the center of the frame 4 along a rack gear 4b provided on both sides of the frame 4. Further, as shown by the two-dot chain line in FIG. 1, the fixture 1 is swivelable in the same direction as the slide direction.
The lower lighting fixtures 2 and 3, as shown in FIG. 1, slide about 650 mm upward on the inward circular arc-shaped rail provided on the holding fixtures 7 and 8 having a radius of about 950 mm, with the position (FIG. 1) about 350 mm above the frame 5 taken as a starting point, and move rotatably within a range of -10° to +35° when the range is straddled by a center line toward the center of the frame, as shown in FIG. 3. The frame 4 is basically of stationary, installed type, whose top side 5 is lined with a plywood plate. The numeral 12 indicates back paper supporting pillars erectly provided on the back of the frame 4, to which a back paper is attached to perform photographing.
FIGS. 6 and 7 show another example of the holding fixtures 7 and 8 of the lower lighting fixture 2. In the above-mentioned example, the lower lighting fixture 2, as shown in FIG. 1, slides about 650 mm upward on the inward circular arc-shaped rail provided on the circular arc-shaped holding fixture 7 or 8, with the position (FIG. 1) about 350 mm above the frame 4 taken as a starting point, and moves rotatably within a range of -10° to +35° when the range is straddled by a center line toward the center of the frame, as shown in FIG. 3. On the contrary, the holding fixtures 7' and 8' shown in FIG. 6 utilize a link mechanism and a telescopic mechanism, and are rotatable 360° about their base portion.
In FIG. 6, the numeral 13 indicates a base board provided on the frame 4. On the base board 13, there is provided a base pillar 14 rotatable 360° in the arrow "a" direction with respect to the base board 13. A first link 15 is supported by a pin 16 with respect to the base pillar 14, rotatable 180° in the arrow "b" direction, and mounted fixably at a specified angle position. A second link 17 is supported by a pin 18 with respect to the first link 15, rotatable 360° in the arrow "c" direction, and mounted fixably at a specified angle position. A third link 19 is supported by a pin 20 with respect to the second link 17. The third link 19 is rotatable 360° in the arrow "d" direction about the pin 20, and mounted fixably at a specified rotating position. A fourth link 21 is mounted in a telescopic manner with respect to the third link 19, and expandable/contractible in the arrow "e" direction.
Because of the above-mentioned composition, the lower lighting fixture 2 or 3 mounted at the top end of the fourth link 21 is changeable freely in the horizontal direction and in the upper/lower direction, and easily permitting fine adjustment of its position by expanding/contracting of the top fourth link 21. With the composition, an optimum changing of the position is possible which is equal to that obtained by the holding fixture of the lower lighting fixture having a composition shown in FIG. 1, thereby allowing an optimum lighting to be given to the subject on the frame 4.
FIG. 7 is an example of the holding fixtures 7" and 8" which expand and contract in a telescopic manner and in the longitudinal/transverse direction. In FIG. 7, a base pedestal 22 is mounted on the frame 4, and a first telescopic pipe 23 is rotatably mounted to the pedestal. A second telescopic pipe 24 is fitted expandably/contractibly into the first telescopic pipe 23. A third telescopic pipe 25 is fitted expandably/contractibly into the second telescopic pipe 24. To the third telescopic pipe 25, there is fixedly mounted a square block 26, to which a horizontally-facing telescopic pipe mechanism 27 is mounted. The lighting fixture 2 or 3 is rotatably mounted by a supporting shaft 28 to the top telescopic member.
With such composition, the holding fixtures 7" (or 8") rotates about the base pedestal and expands/contracts up and down end in the transverse direction, end the lighting fixture itself is rotatable about the supporting shaft 28. Accordingly, in a manner similar to the mechanism shown in FIG. 1, a movement having a very high degree of freedom can be performed.
In order to check the brightness after photographing, as shown in FIGS. 4 (a) and 4 (b), on the frame 4, there can be installed a hemispherical sensor 9 on whose spherical surface a plurality of photodiodes 9a are attached, and which also can automatically check luminous energy.
In performing a light control system in which by, the use of the present equipment, the position and angle of the automatic lighting equipment are set, and the set contents are processed by a personal computer, the following fixtures are prepared. FIG. 5 is a schematic block diagram, in which the top lighting fixture 1 and the lower lighting fixtures 2, 3 of the automatic lighting equipment are controlled in position and angle by a light controller 10. A luminous energy (voltage level) is inputted, which together with position and angle are data processed by a personal computer 11, and as required, the contents are outputted. In this case, the top lighting fixture 1 and the lower lighting fixtures 2, 3 are automatically set by the computer control.
In the embodiments of FIG. 1 through FIG. 3, the top lighting fixture 1 is slidably installed on the circular arc-shaped guide rail 6 provided on the frame 4. However, it is possible to separate the circular arc-shaped guide rail 6 from the frame 4, making the guide rail wider and taller. In this manner, the distance between a subject and lighting fixtures can be made large, and thus more lighting fixtures be set, whereby higher quality photographing and larger-subject photographing can be effectively handled.
The lighting equipment comprises a frame 4; a top lighting fixture 1 which is provided on or separately from the frame 4, slidable right and left along a circular arc-shaped guide rail 6 movable back and forth of the frame 4, and swivelable back and forth on the circular arc-shaped guide rail 6; and lower lighting fixtures 2 and 3 which are provided as a pair on both sides of the frame 4, slidable along circular arc-shaped holding fixtures 7 and 8 with the center of the frame 4 taken as their center, and rotatable in both directions when the range is straddled by a center line toward the center of the frame 4; wherein a mimic subject having a basic size and configuration frequently used in photographing is placed on the frame; its lighting position and luminous energy is adjusted by a photographer having an expertise to obtain an ideal condition; said condition is converted by a position reading device and a photo sensor to an electric signal; an luminous energy to which various portions of the subject are subjected is measured; then, these conditions are input to a computer for storage in memory; end in actual photographing, data are thus automatically selected which are closest to preprogrammed sample data, thereby allowing the lighting work according to said data to be automatically performed.
Instead of the circular arc-shaped holding fixture 7 or 8, holding fixture 7' or 8' comprising in combination a link mechanism and a telescopic mechanism, or holding fixture 7" or 8" comprising in combination telescopic mechanisms causes the degree of freedom to be made larger.
In lighting work affecting greatly the quality and work-hours of photographing, firstly, such composition makes it possible for even those who do not possess a professional technique to produce a lighting condition virtually the same as an advanced lighting technique of professional photographers.
Secondly, such composition makes it possible to shorten significantly photographing time and to provide a uniform lighting without developing variation by individual photograph works. For example, a lighting work conventionally requiring one to three hours can be shortened to several seconds.
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An automatic lighting system simplifies reproduction of desired lighting conditions by use of a computer which compares characteristics of an actual subject to prestored data representing light locations for preferred lighting of a similar mimic subject, and orients mounted lighting fixtures accordingly. A plurality of light fixtures are mounted for movement on frame. Ideal locations of the light fixtures are determined for mimic subjects of various characteristics by a skilled photographer. The location and illumination data are then stored in computer memory. When an actual subject is placed in the same position as the mimic subject for photographing thereof, data for a mimic subject having characteristics closest to the actual subject are selected from the prestored data, and the light fixtures are automatically oriented accordingly in response to computer control. To assure proper orientation and illumination by the light fixtures, a hemispherical sensor including on its surface a plurality of photodiodes may be placed in the position of the subject the output of which is compared against stored data.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to the use of fluorescence spectroscopic imaging, more particularly to the use of fluorescence spectroscopic imaging to diagnose tissue damage.
[0003] 2. Description of Related Art
[0004] Proper characterization of tissue damage (e.g., burns and cuts) is needed for determining an appropriate level of treatment. For example, superficial, partial thickness burns typically heal with conservative management impairment. However, for a burn wound that penetrates the full-thickness of the dermis, surgical intervention may be needed to remove damaged tissue and to cover the wound. Therefore, the characterization of tissue damage as, for example, a superficial versus a penetrating burn, is important for determining a treatment.
[0005] Prior methods of tissue damage characterization have proved to be unreliable and subject to human error. Clinical appraisals of burn damage, including wound depth, are based on observable tissue color and sensitivity. Studies have shown that even an experienced surgeon may be unable to correctly categorize burn depth in as many as one-third of wounds. Histological sections are an alternative to clinical appraisals and can be used to determining burn wound depth. However, sectioning has been criticized because of its invasive nature, the need for multiple biopsies, sampling error, delay in diagnosis due to fixation time and the need for an experienced pathologist.
[0006] Advances in surgical techniques have compounded the problem of tissue damage characterization. For example, laser tissue welding implements a laser beam to join tissues without sutures, thus, a surgeon or other medical personnel needs to characterize the treatment as well as the damage. This distinction can be difficult to make using known techniques.
[0007] Tissue welding can also be referred to as tissue fusion or vessel anastomosis. Tissue welding uses laser light energy to activate photo-thermal bonds and/or photo-chemical bonds within targeted tissues. Laser tissue welding can be used alone or in combination with sutures and/or staples to improve strength and/or sealing characteristics. Besides lasers, which operate with wavelengths in the ultra violet, visible and infrared electromagnetic spectrums, other forms of energy, such as radio and microwave frequencies, can be used to join tissues by fusing component proteins.
[0008] Laser tissue welding has many advantages over conventional suture techniques, such as a reduction in foreign body reaction (e.g., to sutures, staples, etc.), increased rate of healing, lower constriction of tissues and reduced surgical time. Although success has been achieved in experimental and clinical applications, previous work indicates that the bursting strength of laser assisted blood vessel anastomoses is less than that of a conventional suture. Further, in some cases aneurysm formation can be higher than 6 to 29 percent. One reason for these disadvantages is that the intensity of laser irradiation on a weld site is not well proportioned to the tissue damage, therefore, overheating of the tissue can occur. In order to proportion the laser to the damage, precise tissue damage characterization is needed.
[0009] Other laser therapies, such as laser angioplasty, laser recanalization, laser photocoagulation and laser interstitial hyperthemia, also depend on heating a target area. When the photons are absorbed by the tissue, the energy is transformed into heat causing the temperature to rise in the region of adsorption (excited region). One or more photon excitations can lead to protein denaturation, coagulation, and/or ablation.
[0010] All heating therapies depend on the selective control of thermal energy delivery and the degree of thermal tissue damage. Therefore, a need exists for a system and method for in situ detection and characterization of tissue damage and treatment.
SUMMARY OF THE INVENTION
[0011] A method for monitoring a biological tissue is provided, including the steps of illuminating the tissue, including a fluorophore, with a wavelength of light, the wavelength selected for exciting the fluorophore, determining a fluorescent emission intensity of the fluorophore, the emission indicating the presence of the fluorophore, and correlating an emission of the fluorophore to an extent and a degree of damage to the tissue.
[0012] Damage to the tissue includes a breakdown of the fluorophore, resulting in a reduced intensity of emission. The fluorophore can include one of collagen and elastin. The fluorophore can include tryptophan, nicotinamide adenine dinucleotide, flavin and porphyrin.
[0013] Correlating the emission of the fluorophore to the extent and degree of damage further includes correlating the emission over time, controlling the power of a laser welder based on the correlation, and preventing overheating of the tissue by the laser welder. The laser tissue welder implements a beam of light having a bandwidth in the absorption bands of water.
[0014] The method further includes the step of selecting a wavelength based on the tissue's native concentration of one or more fluorophores, wherein a fluorophore of the highest native concentration is selected for correlation to the extent and degree of damage.
[0015] The step of determining a fluorescent emission intensity further comprises the step of determining a relative concentration of the fluorophore over time. The method can further monitor the damage based on the correlation. The damage can include, among others, thermal damage including electrocution, chemical burns, blunt trauma, cuts, and scrapes.
[0016] According to an embodiment of the present invention, a method for monitoring a biological tissue is provided. The method illuminates the tissue including collagen with an illumination bandwidth of about 10 nm to about 100 nm of light and a wavelength between about 340 nm to about 380 nm. The method determines a fluorescent emission intensity of the collagen at an emission wavelength of about 380 nm, an intensity of emission indicating the presence and relative amounts of the collagen over time. Further, the method correlates an emission of the collagen to an extent and a degree of thermal damage to the tissue over time. The method controls the power of a laser welder based on the processed correlation and prevents overheating of the tissue by the laser welder. Similarly, emissions of elastin can be monitored, but at longer wavelengths. These methods correlate an emission intensity in real time and/or in situ.
[0017] The laser tissue welder can implement a beam of light having a wavelength in the absorption bands of water. The laser tissue welder can implement a beam of light having a wavelength in the absorption bands of collagen.
[0018] According to an embodiment of the present invention a monitoring device is provided for detecting thermal damage to a biological tissue and controlling a laser tissue welder. The device includes an illumination device providing a light, a filter provided adjacent to the illumination device to reduce the heat of the light, an optical fiber for directing the filtered light toward the tissue, and a narrow band filter for selecting a bandwidth of light from the filtered light, the bandwidth selected for exciting an emission from a fluorophore of the tissue. The device also includes a camera for collecting a fluorescent emission from the fluorophore, the emission in response to the selected bandwidth of light, a processor for detecting a variation in an emission intensity over time and in response to treatment by the laser tissue welder, and a control means for varying the power of the laser tissue welder in response to a control signal from the processor.
[0019] The processor further includes a correlation means for determining the extent and the degree of the thermal damage. The processor can detect a relative concentration of the fluorophore int eh tissue over time.
[0020] The laser tissue welder implements a light beam having a wavelength between about 1150 nm and about 1500 nm. The laser can be a Cunyite laser, a Forsterite laser, or similar tissue welding laser having a light beam with a wavelength selected for the absorption bands of water and/or a fluorescent protein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Preferred embodiments of the present invention will be described below in more detail, with reference to the accompanying drawings:
[0022] [0022]FIG. 1 a shows the fluorescence spectra of collagen excited by different wavelengths;
[0023] [0023]FIG. 1 b shows the fluorescence spectra of elastin excited by different wavelengths;
[0024] [0024]FIG. 2 is an illustrative diagram of a fluorescence imaging system;
[0025] [0025]FIG. 3 is an illustrative diagram of a daylight illuminated photography system;
[0026] [0026]FIG. 4 shows a repaired tissue sample for cross-section fluorescence imaging;
[0027] [0027]FIG. 5 a shows a surface images of welded tissue, wherein two pieces of tissue were completely welded;
[0028] [0028]FIG. 5 b shows the tissue of FIG. 5 a using collagen fluorescence imaging;
[0029] [0029]FIG. 6 a shows a cross-section of welded tissue using daylight illumination;
[0030] [0030]FIG. 6 b shows the tissue of FIG. 6 a using collagen fluorescence imaging;
[0031] [0031]FIG. 6 c show the tissue of FIG. 6 a using a histological cross-section stained with picrosirius red F3BA and viewed under polarize light;
[0032] [0032]FIG. 7 a shows the surface of a tissue sample after irradiated by argon laser using daylight illuminated photography;
[0033] [0033]FIG. 7 b shows the tissue of FIG. 7 a using native fluorescence imaging;
[0034] [0034]FIG. 8 a shows a cross-section of a tissue sample after irradiated by argon laser using daylight illuminated photography;
[0035] [0035]FIG. 8 b shows the tissue of FIG. 8 a using native fluorescence imaging;
[0036] [0036]FIG. 8 c show the tissue of FIG. 8 a using a histological cross-section stained with picrosirius red F3BA and viewed under polarize light; and
[0037] [0037]FIG. 9 is an illustrative diagram of an imaging system for preventing overheating of tissue during laser tissue welding.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0038] According to an embodiment of the present invention, fluorescence spectroscopy can be used to measure the of electronic transition of fluorophores and chromophores in complex tissue structures. There are several natural fluorophores that exist in tissue which, when excited by ultraviolet light, fluoresce in the ultraviolet and visible regions of the electromagnetic spectrum.
[0039] According to an embodiment of the present invention, the fluorescence of proteins in tissue, and in particular, observable variations in the fluorescence as the result of exposure to various wavelengths of light, can be used to characterize tissue damage and repair. A reduction in protein fluorescence, for example, collagen or elastin emissions, can be used to determine the spatial extent of tissue damage as well as the degree of damage (e.g., the degree to which tissue has been welded). Tissue damage can include, among other things, thermal damage (including electrocution), chemical burns (e.g., acid burns), blunt trauma, cuts and scrapes. The present invention contemplates any tissue damage which manifests as a change in the concentration of a protein exhibiting fluorescence, regardless of whether the change is an increase or decrease.
[0040] Collagen and elastin are examples of photo-active molecules found in most organic tissue. Collagen is an abundant animal protein found in mammals. Collagen contributes to the structural framework of tissues in most organs. Elastin is a protein that contributes to the structure and development of many tissues. Native fluorescence imaging may be performed with selected emission and excitation wavelengths to detect these and/or other proteins.
[0041] Referring to FIGS. 1 a and 1 b , the emission spectra of collagen and elastin are shown respectively, excited with 320 nm, 340 nm and 380 nm lights. An emission wavelength (λ c ) of 380 nm with excitation wavelength (λ ex ) of 340 nm was selected for collagen imaging 102 . For elastin imaging, λ e =450 nm and λ ex =380 nm 104 . It should be noted that any excitation wavelength producing an emission wavelength dependent on the presence or absence of a photo-thermal or photo-chemical bond may be used.
[0042] Referring to FIG. 2, an illustrative diagram of a fluorescence spectroscopic imaging system in accordance with an embodiment of the present invention. A light beam from a high-intensity xenon lamp 202 (e.g., 300W) is sent through a broad band filter 204 to reduce the heat. The light beam is then transmitted by an optic fiber (excitation fiber) 206 to a narrow band filter (excitation filter) 208 prior to illuminating the sample or tissue 210 . The central portion of the bandwidth light beam 212 (e.g., about 10 nm) is used to illuminate the sample 210 . The samples resulting fluorescence can be collected by an F=105 mm ultraviolet (UV) camera lens 214 in a back-scattering geometry. A narrow band filter (emission filter) 216 can be inserted at the front of the lens 214 for fluorescence imaging of the sample 210 . After the signal was amplified by an image intensifier 218 , the fluorescence image can be re-imaged with a second lens 220 onto a charged-coupled device (CCD) camera 222 . Those skilled in the art will recognize in view of the present disclosure that other systems and configurations can be used to image a fluorescence image in accordance with the present invention.
[0043] Three pictures per second can be obtained from this imaging system. To improve the signal-to-noise ratio, each image can be averaged over several pictures (e.g., ten). A personal computer 224 can be used to digitize and analyze the image, though any processor can be used. A control software generates and displays the resulting fluorescence maps.
[0044] The setup used for daylight illuminated photography of the joint is shown in FIG. 3. A glass plate 302 is placed in front of the second lens 214 , replacing the emission filter 216 of FIG. 2, to obtain the same focus and image size as in fluorescence imaging. The sample was illuminated with ambient light, e.g., room lights 304 .
[0045] Referring to FIG. 4, two skin pieces ( 402 and 404 ), about 2 to 2.5 mm thick were placed, free standing, border-to-border on a translation stage. The dermal layers are shown 406 as well as the subcutaneous tissue 408 . Laser tissue welding was performed on the region between the two pieces 410 by scanning the laser irradiation. The stage was moved forward at approximately 5 mm/30 sec., then back at the same speed at the same length. A 5 mm fusion line was formed. No conventional suture was performed. The total exposure time was 5 mm/min. A Cunyite Cr 4+ :Ca 2 GeO 4 tunable laser ( 412 ) at 1,430 nm, and a Forsterite Cr 4+ :M g2 SiO 4 tunable laser ( 412 ) at 1,250 nm were used for laser tissue welding (n=10 for each group). The energy fluencies were 10.5 kj/cm 2 and 19.1 kj/cm 2 , respectively. The main mechanism of Cr 4+ laser (Forsterite and Cunyite) tissue welding uses the absorption bands of water, in the spectral region of about 1,150 nm to about 1,500 nm, to heat and bond tissue, changing the molecular structure of component proteins, e.g., collagen.
[0046] After laser tissue welding was performed, the surface of skin sample was mounted in a quartz slide for native collagen fluorescence imaging as well as daylight illuminated photography. The sample was kept in −20° C. for 15 min. While the sample was frozen, a cross-section (X-Z plane, see FIG. 4) through the center of the welded line 410 and perpendicular to Z-Y plane was selected for imaging the welded region. The fluorescence imaging and daylight illuminated photography were performed on the cut cross-section of the joint region of the sample on the X-Z surface (FIG. 4).
[0047] In another example, a tendon was implemented as the sample. Tendon tissue is a rich-collagen biological test medium. The sample was cut into a 7×7 mm square, about 5 mm in height. Argon laser irradiation was performed perpendicularly to the surface of the bovine tendon sample for a duration of 3, 6, 9, 12 and 15 sec., respectively (n=6 each time group). The sample were mounted in a quartz slide for spectral analysis and daylight illuminated photography. After native fluorescence imaging and photography were performed on the surface of the sample, the sample was kept at −20° C. for 15 min. A cross-section through maximum diameter of the lesion was made. In addition, native fluorescence imaging and photography were performed on the cross-section of the sample at room temperature.
[0048] After spectral analyses and photography, the tissue samples (referring to the skin and tendon samples) were fixed in 10 percent phosphate buffered formalin. The tissues were dehydrated in graded ethanol solution and xylene, and embedded in paraffin. Each of the lesions was sectioned at 5 μm. The sections were treated with Gill's hematoxylin eosin, and picrosirius red F3BA stains. The specimens stained with picrosirius red F3BA were observed with a polarizing microscopic (e.g., a Reichert, Veins, Austria). The other specimens were observed with normal optical microscopic (e.g., Vanox-T, Olympus, Japan). Both microscopes were equipped with a color video camera with three CCD chips (e.g., DXC-97 MD, Sony, Japan) for obtaining histology images.
[0049] According to an embodiment of the present invention, fluorescence spectroscopic imaging can be implemented at selected emission and excitation wavelengths to cause spectral protein emissions. Because light and heat cause protein breakdown, the emissions can be used as an indicator of thermal damage in tissues. Further, the extent (e.g., spatial) of the damage can be precisely determined. Proteins exhibiting fluorescence (fluorophores) include, for example, collagen, elastin, tryptophan, nicotinamide adenine dinucleotide (NADH), flavin and porphyrin. After being treated with a laser, these proteins exhibit reduced fluorescence emissions.
[0050] The region of collagen or elastin loss can be directly observed in fluorescence spectroscopic imaging at selected emission and excitation wavelengths, due to collagen and/or elastin denaturation caused by heating, for example, laser heating. The change in fluorescence intensity can be confirmed by histology with picrosirius red F3BA stain observed under polarizing microscopic and orcein stain (described above).
[0051] A daylight illuminated photograph of the laser tissue welding region on a sample surface is shown in FIG. 3. The two pieces of skin were completely welded. The welded site is invisible in a daylight illuminated photograph, see for example, FIG. 5 a . However, the welded region may be seen as a black line in a fluorescence image (FIG. 5 b ) due to the protein denaturation caused by laser heating and the consequent loss of fluorescence. Thus, a welded site becomes a fluorescence void.
[0052] A depth cross-section of the welded sample is shown by daylight illuminated photography, fluorescence spectroscopic imaging and histological imaging in FIGS. 6 a , 6 b and 6 c , respectively. The welded site was not evident in FIG. 6 a , a daylight illuminated photograph. On the fluorescence spectroscopic image (FIG. 6 b ), the welded site became a fluorescence void, and appears as a crater, due to the collagen or elastin denaturation by laser heating and the consequent loss of fluorescence. The size of the crater in the elastin fluorescence spectroscopic image is less than that in the collagen image. In both the collagen and elastin images, the epidermal layer, the dermal layer, and the subcutaneous layer of the skin sample can be identified by different fluorescence intensities. The crater depth and size in collagen images (FIG. 6 b ) are substantially similar to the thermal damage depth and size as determined in the histological samples with the picrosirius red F3BA stain observed under polarized light (FIG. 6 c ).
[0053] Daylight illuminated photography and native fluorescence imaging of the surface of the damaged tendon sample are shown in FIGS. 7 a and 7 b . The corresponding cross-sectional images from the tissue and histological images are shown in FIGS. 8 a , 8 b , and 8 c . Due to the denaturation of collagen, there is a loss of fluorescence. The fluorescence images in FIGS. 7 b and 8 b show the thermal region. The region of thermal damage becomes dark in the fluorescence image. A narrow zone of gradual fluorescence loss can be seen between the normal and damaged areas. The region of thermal damage in the native fluorescence images (FIGS. 7 b , 8 b ) is much clearer than that of daylight illuminated photography (FIGS. 7 a , 8 a ).
[0054] The diameters of the thermal damage region on the surface, measured from the native fluorescence image and daylight illuminated photograph are listed in Table 1. The diameter (mm) of the thermally damaged regions irradiated is shown at different exposure times at a power density of 274 W/cm 2 .
TABLE 1 Method/ Time (Sec) 3 6 9 12 15 Fluor- 1.40 ± .04 1.84 ± .03 1.95 ± .04 2.39 ± .17 2.81 ± .04 escence imaging Photo- 1.09 ± .02* 1.79 ± .03 1.89 ± .05 2.51 ± .12 2.94 ± .02 graph
[0055] These is a statistic difference between fluorescence image and daylight illuminated photograph (F=10.30497,p=0.00933) measured from 3-sec-irradiation group.
[0056] [0056]FIG. 8 c shows a histological cross-section of the sample stained using picrosirius red F3BA was polarized light. The normal collagen fibers not in laser treated area appear yellow/orange. Some tissue structures disappeared in laser treated region and became homogenized after laser irradiation. The collagen in the damaged region shows evidence of denaturation and loss of its natural birefringence. This region became clear (de-colored) and darker. The damaged region in the slide is similar to that shown in the native fluorescence image (FIG. 8 b ). Both images show stronger thermal damage on the treated tissue region in the center of the damaged region and less below the surface. After a tissue-shrinkage correction factor of 1.15 is multiplied, the maximum depth of the damaged region was measured on the slides stained using picrosirius red F3BA illuminated with polarized light. Table. 2 lists the depth (mm) of thermal tissue damage irradiated at different exposure times at a power density of 274 W/cm 2 measured by native fluorescence imaging, histology and photography.
TABLE 2 Method/ Time (Sec) 3 6 9 12 15 Fluor- 1.07 ± .23 1.57 ± .12 1.68 ± .23 1.82 ± .39 2.13 ± .28 escence imaging Histo- 1.05 ± .15 1.52 ± .22 1.70 ± .34 1.80 ± .27 2.15 ± .31 logy Photo- 0.82 ± .23* 1.61 ± .15 1.63 ± .17 1.77 ± .34 2.08 ± .29 graph
[0057] There is a difference between fluorescence image and daylight illuminated photograph (F=3.5974,p=0.03158) in 3 sec. irradiation group.
[0058] According to an embodiment of the present invention, the optical imaging system shown in FIG. 2 uses an illumination beam from a high-intensity xenon lamp source passed through a narrow band filter (excitation filter) to ensure UV monochromatic irradiation. Fluorescence from the sample can be collected using a UV lense. The collected fluorescence can form an image on a CCD camera after passing through an emission filter.
[0059] Real-time fluorescence imaging can be used to monitor the condition of welded site in situ. No fluorescence intensity change on the welded site means that the tissue has not been heated by laser beam and/or the welding was not effective.
[0060] A perceived change in fluorescence intensity can also be used as a feed-back signal in an automatic laser tissue welding system. (See FIG. 9.) The power of welding laser 902 can be automatically controlled via a processor 904 and controller 906 when a change in fluorescence intensity from the welded tissue 908 is perceived. Thus, collateral tissue damage can be avoided, specifically, overheating of the welded tissue 908 .
[0061] From the teaching of the relationship between tissue fluorescence intensity (variation) and thermal damage of shown in FIGS. 5 b , 6 b , 7 b , and 8 b , the present invention can be used to monitor thermal damage and to measure the depth of laser tissue penetration from a laser or other heating sources. Before the laser ablation surgery or other heating sources treat on the tissue, tissue fluorescence is visible on fluorescence imaging. After the time of the tissue to be heated at the temperature over 65° C., the intensity of the fluorescence from the tissue will be reduced. This change can be determined for treated tissue in situ. The tissue thermal damage or the depth of laser penetration can be displayed and calculated by image processing by the processor 904 . The present invention can also be used to detect the size of a burned tissue area and to estimate the depth of burned wound. If the fluorescence intensity of burned tissue is reduced the tissue has damaged thermally.
[0062] Having described embodiments for non-invasive monitoring of biological tissue via fluorescence, it is noted that modifications and variations can be made by persons skilled in the art in light of the above teachings. It is therefore to be understood that changes may be made in the particular embodiments of the invention disclosed which are within the scope and spirit of the invention as defined by the appended claims. Having thus described the invention with the details and particularity required by the patent laws, what is claimed and desired protected by Letters Patent is set forth in the appended claims.
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A method for monitoring a biological tissue includes illuminating the tissue, including a fluorophore, with a wavelength of light, the wavelength selected for exciting the fluorophore, determining a fluorescent emission of the fluorophore, the emission indicating the presence of the fluorophore, and correlating an emission of the fluorophore to an extent and degree of damage to the tissue. Damage to the tissue includes a breakdown of the fluorophore, resulting in a reduced level of emission. The fluorophore can include one of collagen and elastin. The fluorophore can include tryptophan, nicotinamide adenine dinucleotide, flavin and porphyrin. Correlating the emission of the fluorophore to the extent and degree of damage further includes processing a correlation of the emission over time, controlling the power of a laser welder based on the processed correlation, and preventing overheating of the tissue by the laser welder.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to wind turbines and more particularly pertains to a new blade pitch-controlled wind turbine system for achieving maximum wind efficiency with variable speed and blade pitch control.
2. Description of the Prior Art
The use of wind turbines is known in the prior art. More specifically, wind turbines 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.
The prior art includes a control system including a subtractor for generating a difference signal; a device for generating from the difference signal a first blade control signal greater than a minimum level, from a device for generating a second blade control signal greater than a minimum level, from first blade control signal and the difference signal; a device for generating a third blade control signal for adjusting the pitch of variable-pitch angle blades, from second blade control signal and power rate signal. Another prior art includes a wind power installation having a rotor with at least one blade and an adjusting device for the rotor blade. An adjusting device with more than one drive for one rotor blade is provided. By virtue of that arrangement each drive only has to furnish a corresponding fraction of the power output, it can be of a correspondingly smaller design configuration, and it imposes a correspondingly lower loading on the subsequent components.
Further, another prior art describes a redundant and fail-safe blade system of a wind turbine including at least one blade pitch drive and at least two power control modules for controlling the blade pitch drive. The power control modules are connected to the blade pitch drive by a switching unit which allows an alternative connection between the blade pitch drive and any of the power control modules. In operation, the blade pitch drive is controlled by only one of the power control modules. If a malfunction of the currently operating power control module is detected, switching unit provides a connection to the other power control module to allow an ongoing operation of the wind turbine without an unplanned or forced shut-down. Also, another prior art includes a wind turbine blade pitch system for moving the blades to control their pitch in the event of a power failure. The system includes at least one backup that has a non-electrical component that can pitch the blades in the event that the power failure adversely affects the electrical blade pitch actuator system. Embodiments include pitch systems that have a plurality of pitch driving systems including, but not limited to electrical systems, hybrid electrical/mechanical systems and non-electrical systems. The non-electrical systems include mechanical, pneumatic or hydraulic systems. While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a new blade pitch-controlled wind turbine system.
SUMMARY OF THE INVENTION
The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new blade pitch-controlled wind turbine system which has many of the advantages of the wind turbines mentioned heretofore and many novel features that result in a new blade pitch-controlled wind turbine system which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art wind turbines, either alone or in any combination thereof. The present invention includes a support assembly including a tower; a turbine rotor assembly being supported upon the support assembly; and a blade pitch control assembly being supported upon the support assembly and being in communication with the said turbine rotor assembly. None of the prior art includes the combination of the elements of the present invention.
There has thus been outlined, rather broadly, the more important features of the blade pitch-controlled wind turbine system 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.
It is an object of the present invention to provide a new blade pitch-controlled wind turbine system which has many of the advantages of the wind turbines mentioned heretofore and many novel features that result in a new blade pitch-controlled wind turbine system which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art wind turbines, either alone or in any combination thereof.
Still another object of the present invention is to provide a new blade pitch-controlled wind turbine system for achieving maximum wind efficiency with variable speed and blade pitch control.
Still yet another object of the present invention is to provide a new blade pitch-controlled wind turbine system that pitches the blades most effectively to capture the most wind energy possible.
Even still another object of the present invention is to provide a new blade pitch-controlled wind turbine system that passively brakes the wind turbine rotor without using electrical means thus resulting in less stress being put upon the wind turbine. Also, the passive braking of the blades operates independently of one another should any one of the blades become stuck in a certain position or pitch.
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 made to the accompanying drawings and descriptive matter in which there are 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 a perspective view of a new blade pitch-controlled wind turbine system according to the present invention.
FIG. 2 is a cross-sectional elevational view of the present invention showing blades passively parked into a wind from a right.
FIG. 3 is a cross-sectional elevational view of the present invention showing the blades to be actively pitched for capturing the mot efficient wind energy.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings, and in particular to FIGS. 1 through 3 thereof, a new blade pitch-controlled wind turbine system embodying the principles and concepts of the present invention and generally designated by the reference numeral 10 will be described.
As best illustrated in FIGS. 1 through 3 , the blade pitch-controlled wind turbine system 10 generally comprises a support assembly 11 including a tower 12 being securely supported upon a ground 36 . The support assembly 11 also includes an elongate support member 13 being conventionally supported upon the tower 12 . The support assembly 11 further includes a geared bearing 14 being securely and conventionally disposed upon the tower 12 , and also includes a turbine support member 15 being rotatably and conventionally mounted upon the geared bearing 14 . The support assembly 12 further includes a yaw motor 16 having a motor shaft (not shown) being conventionally supported upon and attached to the turbine support member 15 , and also includes a gear member 17 being rotatably and conventionally connected to the yaw motor 16 and being disposed below the turbine support member 15 and being engageable to the geared bearing 14 for selectively moving the turbine support member 15 upon the actuation thereof.
A turbine rotor assembly 18 is conventionally supported upon the support assembly 11 . The turbine rotor assembly IS includes a hub member 19 having hub bearings 38 and being rotatably and conventionally disposed upon and about the elongate support member 13 . The turbine rotor assembly 18 also includes blade support members 22 a - c being rotatably and pivotally mounted to the hub member 19 and being spaced apart and extending radially therefrom. The hub member 19 includes brackets 20 a - d being conventionally secured thereto with the blade support members 22 a - c being rotatably disposed therethrough, and also includes braces 21 a - b conventionally interconnecting to pairs of the brackets 20 a - d . The turbine rotor assembly 18 further includes blades 23 a - c each being conventionally disposed upon and about a respective blade support member 22 a - c and each having a leading edge 24 a - c . Each of the blade support members 22 a - c is rotatable about its longitudinal axis.
A blade pitch control assembly 34 is supported upon the support assembly 11 and is in communication with the turbine rotor assembly 18 . The blade pitch control assembly 34 includes blade park members 35 a - c which are preferably biased members such as springs each being conventionally disposed about a respective blade support member 22 a - c for urging each blade 23 a - c into a park position to generally prevent rotation of the hub member 19 with the leading edges 24 a - c of the blades 23 a - c substantially facing into a wind when in use. The blade park members 35 a - c could also include hydraulic accumulators and hydraulic cylinders.
The blade pitch control assembly 34 also includes an actuator 25 such as a motor being securely and conventionally mounted upon the elongate support member 13 and being in communication with the blades 23 a - c and having an rotatable member 30 such as a rotational shaft for rotating the blades 23 a - c , and also a conventional brake mechanism 39 being conventionally mounted upon the actuator 25 and including a friction member (not shown) and a spring (not shown) and being in communication with the actuator 25 to prevent movement such as rotation of the actuating member 30 , and further includes a first carrier member 26 which preferably is a pulley but could also be an arm being conventionally connected and bolted to the rotatable member 30 for linear or rotational movement therewith. The blade pitch control assembly 3 also includes an interconnecting member 28 which is preferably a sleeve being in communication with the actuator 25 and being movably and slidably disposed and conventionally retained upon and about the elongate support member 13 and also having an annular recess disposed thereabout.
The blade pitch control assembly 34 further includes first and second linkage members 27 , 33 a - c which are preferably cable members but could also include rigid linkages with the first linkage member 27 being fastened to the outer surface of the interconnecting member 28 using fasteners and being conventionally carried by the first carrier member 26 for moving the interconnecting member 28 linearly along the elongate support member 13 . The blade pitch control assembly 34 further includes a rotatable member 29 such as a collar having a bearing member 37 and being rotatably and conventionally retained by the annular recess about the interconnecting member 28 for rotation with the hub member 19 . The blade pitch control assembly 34 also includes second carrier members 32 a - c which are preferably pulleys each of which is in communication with and conventionally connected and bolted to a respective blade support member 22 a - c for pivoting the blade support members 22 a - c . The second linkage members 33 a - c are conventionally carried by the second carrier members 32 a - c and are fastened to the rotatable member 29 for selectively pivoting the blades 23 a - c to a desired pitch relative to the wind direction when in use. The rotatable member 29 has holes 31 a - c being circumferentially spaced apart and being disposed therethrough for receiving and securing portions of the second linkage members 33 a - c using fastening members.
In use, the pitches of the blades 23 a - c are adjusted according to wind velocity and direction to capture the most efficient wind energy for rotating the turbine rotor assembly 18 . Preferably, an instrument such as a sensor (not shown) measures the wind direction and wind velocity and communicates this information to a processor (not shown) which is in conventional communication with the sensor and which is also in conventional communication with a power source (not shown) and is in further conventional communication with the actuator 25 and the brake mechanism 39 . In response to the sensor, the processor effectively energizes the actuator 25 which moves the interconnecting member 28 via the first carrier member 26 and the first linkage member 27 , upon the elongate support member 13 relative to the turbine rotor assembly 18 to rotate the blades 23 a - c relative to the wind direction to effectively capture the most efficient wind energy. Once the optimal pitches of the blades 23 a - c have been set, the processor energizes the brake mechanism 39 with the friction member (not shown) effectively and conventionally engaging the rotatable member 30 of the actuator 25 to prevent movement of the rotatable member 30 and to prevent movement of the interconnecting member 28 by the blade park members 35 a - c . The blades 23 a - c can be effectively parked automatically without using the actuator 25 to generally prevent the rotation of the turbine rotor assembly 18 . The blades 23 a - c are parked upon the processor de-energizing the brake mechanism 39 which allows the rotatable member 30 to freely move and the blade park members 35 a - c to independently bias the blades 23 a - c and face the leading edges 24 a - c of the blades 23 a - c into the wind thus effectively preventing the wind from impacting the blades 23 a - c and rotating the hub member 19 .
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 blade pitch-controlled wind turbine system. 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 blade pitch-controlled wind turbine system for achieving maximum wind efficiency with variable speed and blade pitch control. The blade pitch-controlled wind turbine system includes a support assembly including a tower; a turbine rotor assembly being supported upon the support assembly; and a blade pitch control assembly being supported upon the support assembly and being in communication with the said turbine rotor assembly.
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BACKGROUND OF THE INVENTION
This invention relates to improvements in a tube-bending machine which performs the bending of a tube or pipe with a mandrel inserted in the tube.
Problems which occur during tube bending with the tube-bending machine of the type specified above includes rupturing of the tube being bent as is ascribable to an insufficient lubrication of the inner surface of the tube, and the appearance of wrinkles on the inner side of the tube bend, the distortion of a tube section or the thinning of the outer side of the tube bend as is attributed to a deviation in the optimum mandrel position.
FIG. 1 is a view for explaining a case of resorting to the radial-draw bending as a typical example of the tube-bending machine (refer to Journal of Mechanical Working Technology, 3 (1979) 151`166). Referring to the figure, a mandrel 1 is inserted into a tube 2, the tube is clamped to a bend die 4 by a clamp die 3, and the bend die 4 is thereafter rotated a predetermined angle, whereby the radial-draw bending machine bends the tube. In the figure, numeral 11 indicates a wiper die and numeral 12 a pressure die, between which the tube 2 is movably supported. With the prior-art tube-bending machine, however, variations in the lubrication condition of the tube and the setting position of the mandrel cannot be detected during the working, and hence, the worked products must be inspected. This leads to the disadvantage of an inferior available percentage of the products.
SUMMARY OF THE INVENTION
This invention has been made with note taken of the above point, and has for its object to provide a tube-bending machine in which fluctuations in the lubrication condition of the inner surface of a tube, the setting position of a mandrel, etc. as stated above are detected during the bending of the tube and which permits the control of the bending condition of the tube and the automation thereof.
In order to accomplish the object, a tube-bending machine according to this invention comprises a mandrel, means to bend a tube with said mandrel inserted in said tube, and means to detect a force acting in an axial direction of said mandrel under the tube bending, so as to sense a bending condition of said tube.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view for explaining an example of a prior-art tube-bending machine,
FIG. 2 is a view for explaining an example of a tube-bending machine according to this invention,
FIG. 3 is a characteristic diagram showing an example of the master curve of an axial force of mandrel-versus-angle of bend curve,
FIG. 4 is a characteristic diagram showing a load curve in the case where the lubrication of the inner surface of a tube is made insufficient,
FIG. 5 is a characteristic diagram showing a load curve in the case where the setting position of a mandrel is changed,
FIG. 6 is a characteristic diagram showing the relationships of the deviation of a mandrel setting position with the axial compression force of a mandrel, the reduction of a wall thickness on the outer side of a tube bend, and the distortion of a tube section,
FIG. 7 is a characteristic diagram showing a load curve in the case where wrinkles have appeared on the inner side of a tube bend, and
FIG. 8 is a diagram for explaining an example of the automation of the control of tube bending conditions.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereunder, this invention will be described with reference to embodiments.
The inventors have found out that, as will be explained later, a force in the axial direction of a mandrel is very susceptible to a bending condition and exhibits a characteristic variation in dependence on the lubrication condition, the variation of the setting position of the mandrel or the appearance of wrinkles. This invention has been made on the basis of such new knowledge, and records a master curve under a predetermined or optimum bending condition in advance, thereby to realize the control of the bending condition during the bending and the automation thereof.
FIG. 2 shows an example of a tube-bending machine according to this invention. Referring to the figure, the example is a radial-draw bending machine in which a tube 2 has a mandrel 1 inserted therein and is clamped to a bend die 4 by a clamp die 3, whereupon the bend die 4 is rotated a predetermined angle thereby to bend the tube. An axial force which acts on the mandrel 1 during the tube bending is transmitted to a load cell 8 which is fixed to a mandrel pedestal 7 by means of a nut 6 fixed to a mandrel bar 5. A force signal detected by the load cell 8 is passed through a strain gauge 9, and is displayed on a recorder 10 as a load curve versus the angle of bend.
FIG. 3 shows an example of the master curve of the load curve under the optimum bending condition in the case of using the spoon mandrel as shown in FIG. 2. In FIG. 3, the axis of abscissas represents the angle of bend of the axis of a tube with respect to the axis of a mandrel on the clamp side, while the axis of ordinates represents the axial force of the mandrel. It is known from the figure that the tension force acting on the mandrel axis presents a peak near an angle of bend of 30° and thereafter decreases, and that the compression force is exhibited after an angle of bend of 80°. While master curves present respectively characteristic forms in dependence on mandrels used, the spoon mandrel will be taken as an example here and the influences of a lubricant and the mandrel setting position on the master curve will be stated hereunder. The material of the tube used is phosphorus-deoxidized copper (Cu: 99.97%, P: 0.02%), and the starting tube has an outside diameter of 9.53 mm and a wall thickness of 0.35 mm. In addition, the radius of bend is 12.5 mm.
FIG. 4 shows a load curve in the case where the lubrication of the inner surface of the tube is made insufficient. The aspect of the curve differs conspicuously, and a great tension force develops. The rupture of the tube is sensed at a point A in the figure.
FIG. 5 shows the variations of a load curve dependent upon the mandrel setting position. When the mandrel is slightly drawn backward in the axial direction, the load curve becomes a curve (b) in which the compression force shifts onto the decreasing side thereof as compared with that of the master curve (a), whereas when the mandrel is slightly pushed forward, the load curve becomes a curve (c) in which the compression force shifts onto the increasing side thereof.
FIG. 6 shows the axial compression force (d), the reduction of a wall thickness (e) on the outermost side of a tube bend and the distortion of a tube section (f) in the case of an angle of bend of 180° as are plotted versus the deviation of a setting position. The reduction of a wall thickness indicates in percentage a value obtained in such a way that a decrement in the wall thickness on the outermost side of the bend, with respect to the wall thickness of the starting tube is divided by the wall thickness of the starting tube, while the distortion of a tube section indicates in percentage a value obtained in such a way that the difference between the major diameter and the minor diameter of the tube section in the middle of the bent portion is divided by the diameter of the starting tube. As apparent from the figure, when the mandrel setting position is shifted onto the backward side, the reduction in the wall thickness decreases, whereas the distortion in the tube section increases. Conversely, when the mandrel setting position is pushed forward, the distortion in the tube section decreases, whereas the reduction in the wall thickness increases. Beyond a forward deviation of 0.25 mm, however, both the reduction in the wall thickness and the distortion in the tube section tend to become substantially constant values. In contrast, the magnitude of the axial compression force becomes greater as the setting position is moved from the backward side onto the forward side more. From the foregoing, it is understood that the reduction of the wall thickness and the distortion of the section of the tube vary depending upon the setting position and that they can be controlled by detecting the axial compression force of the mandrel.
FIG. 7 shows a curve of loads acting on the mandrel at the time when wrinkles have appeared on the inner side of the tube bend. Upon the appearance of the wrinkles, the load curve varies wavily. It has also been confirmed that the number of the final wrinkles agrees with the number of the waves of the load curve.
As described above, the force acting in the axial direction of the mandrel is very susceptible to fluctuations from the optimum conditions of the tube bending, and the automation of the control of the bending conditions is permitted by exploiting this fact.
FIG. 8 is a block diagram which shows an example of the automation of the bending condition control according to this invention. A load curve 14 obtained from tube-bending means 13 during the tube bending is converted by an analog-to-digital converter 15 into a digital value, which is compared with the value of a master curve stored in a ROM (read-only memory) 16 by the use of a digital comparator 17. In case where a greater tension has been detected in the load curve than in the master curve, an alarm of an insufficient lubrication is issued; in case where the maximum compression force has suddenly changed, an alarm of a deviation in the mandrel setting position is issued; and in case where the load curve has varied wavily, an alarm of the appearance of wrinkles is issued. The fluctuation from the optimum bending condition as obtained from the detected result is fed back to the tube-bending means, to correct the lubrication or the mandrel position to the optimum condition. In this case, such correction may be made for the tube itself in real time or may well be made for a tube to be subsequently bent.
As set forth above, the deviation during the bending from the optimum bending condition is sensed by detecting the force acting in the axial direction of the mandrel, and it is fed back, whereby the control of the tube bending condition and the automation thereof become possible. While the radial-draw bending which employs the spoon mandrel has been described here, this invention is also applicable to mandrels in other shapes, for example, flexible ball mandrels such as single-ball mandrel and multi-ball mandrel, etc. and to other tube bending methods, for example, the tube compression bending, the eccentric plug bending, etc. On the other hand, regarding the automation of the bending condition control, the aspect described here is a mere example, and needless to say, various procedures are possible on the basis of the fundamental principle of the present invention that the signal of the force loaded in the axial direction of the mandrel in the course of the bending is detected.
While, in the foregoing embodiments, one example of the master curve indicative of the optimum bending condition has been referred to, it goes without saying that the present invention is not restricted thereto but that the master curve can be appropriately set depending upon a desired bending condition. Furthermore, this invention is not restricted to the concrete numerical values, materials etc. referred to in the foregoing examples, but it can appropriately select and set them depending upon a desired bending condition. In addition, while in the foregoing embodiments this invention has been described with the subject at U-tubes for use in heat exchangers etc., it is not restricted thereto but it has wide applications through proper settings of the angle of bend, etc. and is greatly effective in practical use.
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This invention relates to a tube-bending machine, which is so constructed that force detection means to detect a force acting in the axial direction of a mandrel under a tube-bending operation is disposed on the mandrel of tube-bending means so as to sense bending conditions such as a lubrication condition of an inner surface of a tube being bent and a mandrel position, and further that fluctuations from predetermined bending conditions, of the bending conditions during the tube-bending operation are detected and corrected.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to automotive automatic transmissions, and more particularly to a drum supporting structure installed in the automatic transmission for rotatably supporting an aluminum drum on an aluminum drum support. More specifically, the present invention is concerned with a bearing arrangement installed in the drum supporting structure, by which an undesired centrifugal whirling of the drum about the drum support is suppressed during rotation of the drum.
2. Description of the Prior
In automotive automatic transmissions of a type wherein an aluminum drum is rotatably supported by an aluminum drum support, various drum supporting structures have been hitherto proposed and put into practical use. One of them is such a structure as shown in FIG. 13 .
That is, in such a conventional drum supporting structure, a first steel sleeve 104 is press-fitted in a larger diameter bore of the aluminum drum 103 , a second steel sleeve 105 is press-fitted on a smaller diameter portion of the aluminum drum support 102 and a steel ring 111 is fitted to a raised wall of the drum support 102 . Upon assembly, the first steel sleeve 104 is carried on three seal rings 102 a , 102 b and 102 c mounted on a larger diameter portion of the drum support 102 , the second steel sleeve 105 carries thereon a cylindrical inner wall of a smaller diameter bore of the drum 103 , and the steel ring 111 bears an axial base end of the drum 103 , as shown.
That is, in the illustrated conventional drum supporting structure, three steel members, which are the first and second steel sleeves 104 and 105 and the steel ring 111 , are interposed between the aluminum drum support 102 and the aluminum drum 103 . However, practical supporting of the aluminum drum 103 on the aluminum drum support 102 is carried out by only the second steel sleeve 105 . That is, due to presence of the three seal rings 102 a , 102 b and 102 c between the first steel sleeve 104 and the aluminum drum support 102 , the first steel sleeve 104 does not participate in supporting the drum 103 on the drum support 102 . That is, a so-called one point supporting is employed in the illustrated conventional drum supporting structure.
However, the one point supporting tends to bring about undesired centrifugal whirling of the drum 103 relative to the drum support 102 when the drum 103 rotates about the drum support 102 . This phenomenon becomes much severe when the axial length of the drum 103 increases.
Furthermore, usage of the three steel members 104 , 105 and 111 has brought about a time-consumed and troublesome assembling work. Particularly, fixing the steel ring 111 to the raised wall of the drum support 102 has needed a very skilled technique. These have caused a costly assemblage of the transmission. Furthermore, in such drum supporting structure, it has been difficult to feed a sufficient amount of lubrication oil to an end clearance 110 which inevitably appears between the drum support 102 and the drum 103 at a position between the first steel member 104 and the steel ring 111 . In fact, even when an oil passage “O” is provided in the larger diameter portion of the drum support 102 to lubricate such end clearance 110 by using a lubrication oil flowing in a lubrication oil passage formed in an output shaft OUT, adequate oil feeding to the clearance 110 is not expected.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a drum supporting structure for an automotive automatic transmission, which is free of the above-mentioned drawbacks.
According to the present invention, there is provided a drum supporting structure for use in an automatic transmission. The automatic transmission includes a transmission case, an aluminum drum support fixed to the transmission case, an aluminum drum rotatably held by the drum support, a piston installed in the drum, a hydraulic fluid passage formed in the drum to feed the piston with a hydraulic work, a lubrication oil passage formed in the drum support to feed the piston with a lubrication oil, and seal rings for hermetically separating the lubrication fluid passage and the lubrication oil passage. The drum supporting structure comprises larger and smaller diameter portions and a radially raised wall portion which are defined by the aluminum drum support, the radially raised wall portion being arranged at an axially base end of the larger diameter portion, the larger diameter portion having the seal rings concentrically mounted thereon; larger and smaller diameter bores defined by the aluminum drum to respectively receive therein the larger and smaller diameter portions of the drum support allowing an axially base end of the drum to face the radially raised wall portion of the drum support; a first steel sleeve coaxially fitted to a cylindrical inner wall of the larger diameter bore, the first steel sleeve including a cylindrical major portion which is slidably put on the seal rings and a cylindrical end portion which is slidably and directly supported on the larger diameter portion of the aluminum drum support, the cylindrical major portion and the cylindrical end portion being integrally connected to constitute a single unit; and a second steel sleeve coaxially fitted to a cylindrical outer wall of the smaller diameter portion of the drum support to bear a cylindrical inner wall of the smaller diameter bore of said drum.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the present invention will become apparent from the following description when taken in conjunction with the accompanying, in which:
FIG. 1 is a sectional view of an automotive automatic transmission to which the present invention is practically applied;
FIG. 2 is a power train possessed by the automatic transmission to which the present invention is practically applied;
FIG. 3 is a table showing various conditions taken by various friction elements used in the automatic transmission to which the invention is practically applied;
FIG. 4 is a view similar to FIG. 2, but showing a torque transmission path that is established when the automatic transmission assumes First gear;
FIG. 5 is a view similar to FIG. 2, but showing a torque transmission path that is established when the automatic transmission assumes Second gear;
FIG. 6 is a view similar to FIG. 2, but showing a torque transmission path that is established when the automatic transmission assumes Third gear;
FIG. 7 is a view similar to FIG. 2, but showing a torque transmission path that is established when the automatic transmission assumes Fourth gear;
FIG. 8 is a view similar to FIG. 2, but showing a torque transmission path that is established when the automatic transmission assumes Fifth gear;
FIG. 9 is a view similar to FIG. 2, but showing a torque transmission path that is established when the automatic transmission assumes Reverse gear;
FIG. 10 is an enlarged sectional view of an upper half of a part of the automatic transmission where a drum supporting structure of the present invention is installed;
FIG. 11 is an enlarged sectional view of the entirety-of the part of the automatic transmission where the drum supporting structure of the present invention is installed;
FIG. 12 is a view similar to FIG. 11, but showing a modification of the drum supporting structure of the present invention; and
FIG. 13 is an enlarged sectional view of an upper half of a conventional drum supporting structure.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1 and 2, there is shown an automotive automatic transmission to which the present invention is practically applied.
In the drawings, particularly in FIG. 2, designated by G 1 , G 2 and G 3 are first, second and third planetary gear units, designated by M 1 and M 2 are first and second connecting members, designated by C 1 , C 2 and C 3 are first, second and third clutches, designated by B 1 , B 2 , B 3 and B 4 are first, second, third and fourth brakes, designated by F 1 , F 2 and F 3 are first, second and third one-way clutches and designated by “IN” and “OUT” are input and output shafts respectively.
The first planetary gear unit G 1 is of a single pinion type that comprises a first sun gear S 1 , a first ring gear R 1 , a first pinion (not shown) engaged with both the first sun gear S 1 and the first ring gear R 1 and a first carrier PC 1 carrying the first pinion.
The second planetary gear unit G 2 is also of a single pinion type that comprises a second sun gear S 2 , a second ring gear R 2 , a second pinion (not shown) engaged with both the second sun gear S 2 and the second ring gear R 2 and a second carrier PC 2 carrying the second pinion.
The third planetary gear unit G 3 is also of a single pinion type that comprises a third sun gear 53 , a third ring gear R 3 , a third pinion engaged with both the third sun gear S 3 and the third ring gear R 3 and a third carrier PC 3 carrying the third pinion.
The first connecting member M 1 integrally connects the first carrier PC 1 and the third ring gear R 3 .
The second connecting member M 2 integrally connects the second ring gear R 2 and the third carrier PC 3 .
The first clutch C 1 selectively establishes connection or disconnection between the first ring gear R 1 and the second ring gear R 2 .
The second clutch C 2 selectively establishes connection or disconnection between the second sun gear S 2 and the third sun gear S 3 . To this second clutch C 2 , there is connected the first one-way clutch F 1 in parallel.
The.third clutch C 3 selectively establishes connection or disconnection between the third carrier PC 3 and the third sun gear S 3 .
The first brake B 1 selectively brakes rotation of the second connecting member M 2 .
The second brake B 2 selectively brakes rotation of the first sun gear S 1 . To this second brake B 2 , there is connected the second one-way clutch F 2 in parallel.
The third brake B 3 selectively brakes rotation of the second sun gear S 2 . To this third brake B 3 , there is connected in parallel a unit that includes the fourth brake B 4 and the third one-way clutch F 3 which are arranged in series as shown.
The input shaft IN is connected to the first ring gear R 1 , so that an engine torque is applied to the first ring gear R 1 through a torque converter (not shown).
The output shaft OUT is connected to the second carrier PC 2 , so that an output torque from the second carrier PC 2 is transmitted to drive wheels (not shown) through a final gear unit (not shown).
To the clutches C 1 , C 2 and C 3 and the brakes B 1 , B 2 , B 3 and B 4 , there are connected a hydraulic pressure control device by which engaging pressure and releasing pressure for such friction elements are produced. The hydraulic pressure control device may be of a mechanically controlling type, an electronically controlling type or a combination of these two types.
FIG. 3 is a table showing various conditions taken by the various friction elements when the automatic transmission assumes First, Second, Third, Fourth, Fifth and Reverse gears.
In the table of FIG. 3, mark “Δ” represents that the corresponding friction element participates in torque transmission when assuming ON condition (viz., power ON), mark “C” represents that the corresponding friction element participates in torque transmission when the corresponding vehicle is under coasting, mark “ 574 ”represents that the corresponding friction element has no effect on the output of the transmission even when applied with a hydraulic pressure, mark “(O)” represents that the corresponding friction element takes an engaged condition under overrun mode, mark “(O)*” represents that the corresponding friction element assumes an engaged condition at the time when the corresponding gear (viz. first gear) is selected and thereafter the friction element takes a disengaged condition in a mode other than the overrun mode, and mark “O” represents that the corresponding friction element takes an engaged condition.
FIGS. 4 to 9 are schematic illustrations of power train showing respective torque transmission paths that are established when the automatic transmission assumes First, Second, Third, Fourth, Fifth and Reverse gears.
Referring to FIGS. 10 and 11, there is shown a part of the automatic transmission where a drum supporting structure of the present invention is practically arranged.
In FIG. 10, denoted by numeral 1 is a transmission case. An aluminum drum support 2 is immovably installed in the transmission case 1 . Rotatably supported by the aluminum drum support 2 is an aluminum drum 3 . Operatively installed in the drum 3 is a piston 6 . The drum 3 is engageable with the above-mentioned first reverse brake B 1 and third clutch C 3 in a known manner, and the drum 3 is connected to the above-mentioned third pinion carrier PC 3 to rotate together, in a known manner.
As will be described in detail hereinafter, the aluminum drum 3 has a first steel sleeve 4 press-fitted thereto to be frictionally sustained by the drum support 2 , and the aluminum drum support 2 has a second steel sleeve 5 press-fitted thereto to frictionally sustain the drum 3 . The entire arrangement of the first and second steel sleeves 4 and 5 and the positional relation therebetween are well understood from FIG. 11 which shows in detail the exact portion where the aluminum drum 3 is rotatably supported by the aluminum drum support 2 .
As is shown in FIG. 11, the drum support 2 comprises coaxial larger and smaller diameter portions “L 2 ” and “S 2 ” which have a first radially raised wall “R 2 - 1 ” provided therebetween. The drum support 2 further comprises a second radially raised wall “R 2 - 2 ” that is integrally formed on an axially base end of the larger diameter portion “L 2 ”.
The larger and smaller diameter portions “L 2 ” and “S 2 ” of the drum support 2 respectively support larger and smaller diameter portions “L 3 ” and “S 3 ” of the drum 3 . More specifically, the larger and smaller diameter portions “L 2 ” and “S 2 ” of the drum support 2 respectively support inner walls of larger and smaller cylindrical bores of the larger and smaller diameter portions “L 3 ” and “S 3 ” of the drum 3 , as shown.
The larger diameter portion “L 2 ” of the drum support 2 is 15 formed at its cylindrical outer wall with two annular grooves 21 and 22 for flowing hydraulic work fluid. Each groove 21 or 22 is hermetically sealed by seal rings 2 a and 2 b (or, 2 b and 2 c ) operatively disposed on the cylindrical outer wall of the larger diameter portion “L 2 ”.
As shown in FIG. 11, the annular groove 22 is connected with a working fluid passage 22 A that extends axially in the drum support 2 . Although not shown in the drawing, another working fluid passage is formed in the drum support 2 , which is connected with the other annular groove 21 .
The drum support 2 is further formed with an axially extending oil passage 2 g that has first and second branch passages 2 h and 2 i . The first branch passage 2 h leads to the bottom of the first radially raised wall “R 2 - 1 ” and the second branch passage 2 i leads to the outer wall of the larger diameter portion “L 2 ”, as shown. Through these oil passages 2 g , 2 h and 2 i , lubrication oil is led to various portions between the drum support 2 and the drum 3 where lubrication is needed. Although not shown in the drawings, the transmission case 1 is formed with passages through which the lubrication oil is conveyed to the oil passage 2 g.
It is to be noted that the cylindrical outer wall of the larger diameter portion “L 2 ” has near the axially base end thereof an annular bearing ridge 2 f . The annular bearing ridge 2 f lies between two smaller lubrication oil grooves 2 d and 2 e formed at the outer wall of the larger diameter portion “L 2 ”. As shown, the groove 2 e is provided at the axially base end of the larger diameter portion “L 2 ”.
The smaller diameter portion “S 3 ” of the drum 3 is formed at the cylindrical inner wall thereof with an oil passage 31 and an annular oil groove 32 . The oil passage 31 serves to convey the lubrication oil from the first branch passage 2 h to the annular oil groove 32 .
The drum 3 is further formed with passages 33 , 34 and 35 which serve to feed the piston 6 with the hydraulic work fluid.
The first steel sleeve 4 is press-fitted on the cylindrical inner wall of the larger diameter portion “L 3 ” of the drum 3 and rotatably sustained on the larger diameter portion “L 2 ” of the drum support 2 .
As shown, the first steel sleeve 4 is of a single member which comprises a cylindrical major portion 4 a , a cylindrical end portion 4 b and an annular flange portion 4 c which are coaxially arranged. As shown, the cylindrical major portion 4 a and the cylindrical end portion 4 b are integrated and arranged to entirely cover the cylindrical inner wall of the larger diameter portion “L 3 ” of the drum 3 , and the annular flange portion 4 c is integrally connected to the cylindrical end portion 4 b and arranged to cover a radially raised wall of the axially base end of the larger diameter portion “L 3 ”, as shown.
It is to be noted that the cylindrical major portion 4 a of the first steel sleeve 4 is slidably put on the three seal rings 2 a , 2 b and 2 c and the cylindrical end portion 4 b of the sleeve 4 is directly supported on the annular bearing ridge 2 f of the drum support 2 . In other words, in the first steel sleeve 4 , the cylindrical major portion 4 a does not participate in supporting the drum 3 on the drum support 2 . That is, only the cylindrical end portion 4 b of the sleeve 4 does such supporting function. For lubrication of the cylindrical end portion 4 b and the annular bearing ridge 2 f , lubrication oil is fed to such portions through the second branch passage 2 i of the axially extending oil passage 2 g of the drum support 2 .
The annular flange portion 4 c bears the second radially raised wall “R 2 - 2 ” of the drum support 2 . The annular flange portion 4 c is formed with radially extending oil grooves 4 d . These oil grooves 4 d are communicated with the second branch passage 2 i.
The first steel sleeve 4 is further formed with openings 41 and 42 for feeding the hydraulic work fluid to hydraulic work chambers 6 a and 6 b of the piston 6 .
The second steel sleeve 5 is of a single member that covers a cylindrical outer wall of the smaller diameter portion “ 52 ” of the drum support 2 . The second steel sleeve 5 bears the cylindrical inner wall of the smaller diameter portion “S 3 ” of the drum 3 , as shown.
The piston 6 is biased rightward in FIG. 11 by a spring 6 d installed in a centrifugal force canceling chamber 6 c . The hydraulic work chambers 6 a and 6 b are provided at a position opposite to the force canceling chamber 6 c . A passage 61 is formed in the piston 6 to feed the hydraulic work chamber 6 a with the hydraulic work fluid.
In the following, advantageous features of the present invention will be described with reference to the drawings.
As is understood from FIGS. 9 and 10, in Reverse gear, the drum 3 connected to the third pinion carrier PC 3 is fixed to the transmission case 1 by means of the first brake B 1 . While, as is seen from FIGS. 4 to 8 , in First, Second, Third, Fourth or Fifth gear, the drum 3 is released from the transmission case 1 and driven by the third pinion carrier PC 3 . That is, when the transmission takes a gear position other than Reverse gear, the drum 3 is always rotated relative to the drum support 2 . To this rotation, the drum supporting structure of the invention exhibits the following advantageous functions.
First, to rotatably support the aluminum drum 3 on the aluminum drum support 2 , the first and second steel sleeves 4 and 5 are employed, which are spaced from each other in an axial direction. That is, as has been mentioned hereinabove, in addition to the second steel sleeve 5 , the cylindrical end portion 4 b of the first steel sleeve 4 is directly supported on the drum support 2 . A so-called two point supporting of the drum 3 on the drum support 2 is achieved. Thus, undesired centrifugal whirling of the drum 3 under rotation of the same is suppressed. Furthermore, due to the same reason, a force inevitably applied to the seal rings 2 a , 2 b and 2 c from the drum 3 is reduced, which protects contacting surfaces of the seal rings 2 a , 2 b and 2 c.
Second, the first steel sleeve 4 serves to bear a radial force as well as an axial force which are inevitably applied to the drum 3 when the drum 3 is rotated. More specifically, the cylindrical end portion 4 b of the first sleeve 4 serves to bear the radial force and the annular flange portion 4 c serves to bear the axial force. The second steel sleeve 5 serves to bear the radial force.
Third, the lubrication oil from the first branch passage 2 h (see FIG. 11) of the drum support 2 is fed to the centrifugal force canceling chamber 6 c as well as to the second steel sleeve 5 . For the oil feeding to this sleeve 5 , the oil passage 31 and the annular oil groove 32 are effectively used. Furthermore, the lubrication oil from the second branch passage 2 i is fed to the two smaller oil grooves 2 d and 2 e of the drum support 2 and to the oil grooves 4 d of the annular flange portion 4 c . With this, lubrication at the supporting annular ridge 2 f , the cylindrical end portion 4 b and the annular flange portion 4 c is made well.
Fourth, the first steel sleeve 4 is fixed to the drum 3 to rotate therewith. Thus, upon rotation of the drum 3 , the lubrication oil in the radially extending oil grooves 4 d of the annular flange portion 4 c is forced to flow radially outward due to the centrifugal force. This promotes the lubrication at the annular flange portion 4 c.
Referring to FIG. 12, there is shown a modification of the drum supporting structure of the present invention.
Since this modification is similar in construction to the above-mentioned drum supporting structure, only different portions will be described in the following.
In this modification, a third steel sleeve 7 is further employed in addition to the first and second steel sleeves 4 and 5 . As shown, the third steel sleeve 7 is press-fitted on the larger diameter portion “L 2 ” of the drum support 2 and has structures that correspond to the annular grooves 21 and 22 and the seal rings 2 a , 2 b and 2 c.
Due to usage of the third steel sleeve 7 , the durability at the portion where the seal rings 2 a , 2 b and 2 c are provided is much assured.
The entire contents of Japanese Patent Application 11-296458 (filed Oct. 19, 1999) are incorporated herein by reference.
Although the invention has been described above with reference to the embodiments of the invention, the invention is not limited to such embodiments as described above. Various modifications and variations of such embodiments may be carried out by those skilled in the art, in light of the above descriptions.
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The drum supporting structure comprises larger and smaller diameter portions and a radially raised wall portion which are defined by the aluminum drum support, the radially raised wall portion being arranged at an axially base end of the larger diameter portion and the larger diameter portion having seal rings concentrically mounted thereon; a first steel sleeve coaxially fitted to a cylindrical inner wall of the larger diameter bore, the first steel sleeve including a cylindrical major portion which is slidably put on the seal rings and a cylindrical end portion which is slidably and directly supported on the larger diameter portion of the drum support and a second steel sleeve coaxially fitted to a cylindrical outer wall of the smaller diameter portion of the drum support to bear a cylindrical inner wall of the smaller diameter bore of the drum.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application is the U.S. national phase of International Application No. PCT/EP2010/063179 filed on Sep. 8, 2010, which application claims priority to German Patent Application No. DE202009012158.5 filed on Sep. 8, 2009, the contents of both of which are incorporated herein by reference.
FIELD OF THE INVENTION
The invention relates to a rotary lobe pump for conveying a fluid medium containing solids, said rotary lobe pump comprising two rotary lobes each having rotary lobe vanes engaging with other and each having a rotational axis and an outer periphery, wherein the rotational axes of the two rotary lobes are spaced apart from each other and arranged parallel to each other and wherein the outer peripheries of the two rotary lobes partially intersect each other, and further comprising a housing with an inlet opening and an outlet opening and an inner wall and an outer wall, the inner wall of the housing enclosing a respective section of the outer peripheries of the rotary lobes and wherein the rotary lobe pump is adapted to convey the medium in a feeding direction from the inlet opening to the outlet opening.
BACKGROUND
Rotary lobe pumps fall into the category of displacement pumps and have two rotary lobes each with two or more rotary lobe vanes. The rotary lobes are disposed in a housing, the inner wall of which faces the rotary lobes and the outer wall of which encloses the rotary lobe pump on the outside. With its inner wall, the housing encloses respective sections of the outer peripheries of the rotary lobes. The section enclosed by the inner housing wall is also referred to as the enclosed angle. The tips of the rotary lobe vanes may be provided with a coating, preferably a sealing face made of rubber, in order to create a seal between the rotary lobe vanes and the inner housing wall and between the rotary lobe vanes as they engage with each other. The rotary lobes are each driven rotatably about a rotational axis in respective opposite directions, an outer periphery of each rotary lobe being defined by the circular paths on which the tips of the rotary lobe vanes turn. In the region in which the rotary lobe vanes engage with each other, the two outer peripheries of the rotary lobes intersect. Rotary lobe pumps are generally symmetrical in structure in order to allow the feeding direction to be reversed.
Rotary lobe pumps with the type of construction initially specified are known, for example, from DE 297 23 984 U1, DE 34 27 282 A1, U.S. Pat. No. 2,848,952, NL 101 62 83, U.S. Pat. No. 3,126,834 and U.S. Pat. No. 15,221. Rotary lobe pumps of this kind are also used to convey media which contain solids. A fluid medium, generally a liquid which may contain various kinds and amounts of solids, is fed through the inlet opening into the region where the rotary lobes intersect and is displaced onwards to the outlet opening by the rotary lobe vanes. Media of different viscosities may be conveyed. Rotary lobe pumps of the kind initially specified have feed rates ranging, for example, from approximately 3 to 1,000 cubic meters per hour, i.e., approximately 50 to 16,667 liters per minute, and pressures of up to approximately 16 bar.
Solids contained in the medium are swept with the medium into the cavities between the rotary lobe vanes and transported with the medium in the feeding direction of the rotary lobe pump from the inlet opening to the outlet opening. Solids contained in the medium may be stones, metal parts or other foreign matter, for example.
Rotary lobe pumps are frequently deployed in challenging environments. Typical fields of application for rotary lobe pumps are, for example, sewage plants, black water and wastewater engineering, disposal and recycling engineering, the paper and cellulose industry, rail and opening operations, the food industry and the construction industry. Rotary lobe pump are used, inter alia, as sludge pumps, wastewater pumps, black water or grey water pumps, thick matter pumps, animal feed pumps, mobile pumps, pumps for media contaminated with foreign matter, liquid manure pumps, feces pumps or pumps for stillage and pulp. These deployment contexts require rotary lobe pumps to have a robust, reliable and tough design.
However, pump component damage, shut-downs and severe wear and tear are recurrent phenomena in the case of existing rotary lobe pumps, as solids are not always transported in their entirety into the cavities between the rotary lobe vanes, where they are displaced onwards, but may become trapped between the rotary lobe vanes and the housing, or between two rotary lobe vanes as they engage with each other. Solids may become stuck between rotary lobe vanes and the housing, or between two rotary lobe vanes of the two rotary lobes as they engage with each other, which may result in the pump shutting down, in damage or wear of the housing and/or of the rotary lobes, in particular of the rotary lobe vanes and in particular of any (sealing) coating on the tips of the rotary lobe vanes. Shut-downs lead to unwanted operational disruptions and damage, and wear and tear of the rotary lobes and/or the housing result in reduced efficiency of the pump due to reduced feed pressure and in higher costs due to the need for repairs and for the replacement of wearing parts and replacement parts.
In order to eliminate these disadvantages, it is proposed in DE 20 2005 010 467 U1 and in DE 20 2006 020 113 U1 held by the applicant that the housing enclose the outer peripheries of the rotary lobes beyond a housing half angle α of 90° on the inlet side and on the outlet side, as shown in FIG. 1 . Although the above disadvantages can be decreased as a result of this reduction in the cross-section of the inlet opening and outlet opening on the inner wall of the housing, there is still a need for further improvement of rotary lobe pumps in order to prevent the disadvantages mentioned above.
BRIEF SUMMARY
The object of the present invention is therefore to provide a rotary lobe pump for conveying a fluid medium containing solids that reduces or eliminates one or more of the aforementioned disadvantages. Another object of the present invention is to provide a rotary lobe pump for conveying a fluid medium containing solids, which reduces the number of shut-downs and the wear on the rotary lobe pump and its components and/or which reduces any decrease in the efficiency or feed pressure of the rotary lobe pump even over a protracted period of operation and/or in challenging environments.
The object is achieved, according to the invention, by the outlet opening on the inner wall of the housing having a maximum discharge enlargement that is greater in a direction running parallel to the plane of the rotational axes and perpendicularly to the rotational axes than the distance between the rotational axes.
The outlet opening is an opening provided in the housing such that the outlet opening passes through both the inner wall and the outer wall of the housing. The enlargement on discharge is defined as the enlargement of the outlet opening that occurs on the inner wall of the housing, namely in a direction that is perpendicular to both rotational axes and which connects those rotational axes.
Rotary lobe pumps are often used in an operating position in which the rotational axes of the rotary lobes are horizontally oriented and are arranged vertically one above the other. In this case, the enlargement on discharge is in the vertical direction, i.e., parallel to the plane of the rotational axes and perpendicular to the rotational axes. However, other operating positions of rotary lobe pumps are also possible, for example with rotational axes which are vertically oriented and arranged horizontally adjacent to each other. In this case, the enlargement on discharge would run in the horizontal direction.
According to the invention, the enlargement on discharge is larger than the distance between the rotational axes and therefore larger than in the solutions shown in the prior art. Thus, the section of the outer peripheries that is enclosed by the inner wall of the housing is smaller in the region of the outlet opening than in the solutions shown in the prior art.
The invention is based on the realization that, on the outlet side of existing rotary lobe pumps, there is an outlet current or formation of vortices in the medium, which frequently causes solids at the outlet opening to come between the rotary lobe vanes and the housing, or between two rotary lobe vanes as they engage with each other, and which may lead to damage, wear and shut-downs. Due to the enlargement on discharge that is formed in accordance with the invention, the solids are released from the rotary lobe vanes earlier. This causes the tangential direction in which the solids are flushed out of the cavities between the rotary lobes to lead away from the opposite rotary lobe vanes. As a result, the paths of motion of the solids changes advantageously, compared to existing solutions, in such a way that the solids are guided away from the rotary lobes, in particular from rotary lobe vanes of the respective opposite rotary lobe. This change in the path of motion of the solids leads to a clear reduction in the amount of solids that, at the outlet opening, come between the rotary lobe vanes and the housing wall, or between two rotary lobe vanes engaging with each other. These advantages are manifested particularly clearly in the case of solids that have a specific weight greater than that of the medium.
This reduction in the sensitivity of the rotary lobe pump to foreign matter makes it possible, in particular, to reduce the number of shut-downs of the rotary lobe pump and the amount of wear on the rotary lobes, and to reduce any decrease in the feed pressure of the rotary lobe pump even when there is a high content of solids in the medium. The solution according to the invention also allows the service life of the rotary lobe pump to be extended and the costs for repair and maintenance of the rotary lobe pump to be reduced.
The cross-section of the enlargement on discharge may be of any shape, for example circular or oval. It is preferred that the die enlargement on discharge is larger along the entire width of the outlet opening than the distance between the rotational axes, as the positive effect on the path of motion of the solids also declines when the enlargement on discharge is less in some sections than the distance between the rotational axes. It is preferred, more specifically, that the outlet opening has a rectangular or square cross-section such that the enlargement on discharge is substantially constant across the entire width of the outlet opening.
According to the invention, the rotary lobe pump is preferably developed in such a way that the discharge enlargement is greater than an enlargement at the inner wall of the housing in a direction running parallel to the plane of the rotational axes and perpendicularly to the rotational axes. This development thus abandons the symmetrical structure of the rotary lobe pump with identically designed inlet and outlet opening, since both the reduction of the enclosed angle in the region of the outlet opening and also a larger enclosed angle in the region of the inlet opening reduce clogging with solids between the rotary lobe vanes and the housing wall or between two rotary lobe vanes engaging with each other. Since the flow conditions, and also the formation of vortices, for example, on the inlet side of the rotary lobe pump on which the medium is drawn in, are different from those on the outlet side of the rotary lobe pump, on which the medium is forced out under pressure, different shapes of the inlet opening and outlet opening, adapted to the respective pressure conditions, are also advantageous for preventing or reducing clogging with solids, not only at the inlet opening, but also at the outlet opening.
The invention is preferably developed by having the cross-section of the outlet opening taper from the inner wall of the housing to the outer wall of the housing. In this development of the invention, the cross-section of the outlet opening at the inner wall of the housing is larger than the cross-section of the outlet opening at the outer wall of the housing.
When forming the outlet opening in the housing, side faces of the outlet opening ensue between the inner and the outer wall of the housing along the periphery of the outlet opening. These side faces can also be referred to as discharge ramps. In this development of the invention, at least one of the discharge ramps is sloped in such a way that the outlet opening tapers in the feeding direction of the rotary lobe pump. Such tapering of the outlet opening in the feeding direction reduces turbulence and vortices in the region of the outlet opening. As a result, the solids are advantageously steered more strongly in paths of motion that prevent or reduce any clogging with solids between rotary lobe vanes and the housing, or between two rotary lobe vanes as they engage with each other. By shaping the discharge ramps in accordance with the invention, it is also possible, therefore, to reinforce the advantages achieved by reducing the enclosed angle.
One particularly preferred development of the invention is one in which the rotational axes of the rotary lobes are horizontally oriented and vertically arranged one above the other when the rotary lobe pump is in the operating position. In this case, the enlargement on discharge extends in the vertical direction. In such a development of the invention, it is also particularly preferred that the outlet opening has a rectangular or square cross-section, in which the lower and the upper side faces or discharge ramps slope in the feeding direction towards the middle axis of the outlet opening. The width of the outlet opening may be exactly as large at the inner wall of the housing as at the outer wall of the housing, with the result that there is no sloping of the side faces.
The invention is preferably developed by the outlet opening on the inner wall of the housing having a maximum enlargement that is greater in a direction running parallel to the plane of the rotational axes and perpendicularly to the rotational axes than the distance between the rotational axes. It is particularly preferred that the outlet opening on the inner wall of the housing has an enlargement that is less in a direction running parallel to the plane of the rotational axes and perpendicularly to the rotational axes than the distance between the rotational axes. These variants of the discharge ramps are particularly advantageous with regard to influencing the paths of motion of the solids, such that clogging with the solids between the rotary lobe vanes and the housing, or between two rotary lobe vanes engaging with each other can be prevented even more reliably.
Another preferred development of the invention is characterized by a pipe connector flange which surrounds the outlet opening and has a middle axis that is offset from a middle axis of the outlet opening at the outer wall of the housing. It is particularly preferred that the rotational axes of the rotary lobes are horizontally oriented and arranged vertically one above the other when the rotary lobe pump is in an operating position and that the middle axis of the pipe connector flange is offset vertically downwards in relation to the middle axis of the outlet opening at the outer wall of the housing.
In order that the rotary lobe pump can be connected as part of a piping system in which the pumped medium runs, the rotary lobe pump is preferably provided with a pipe connector flange. The pipe connector flange preferably has connection means to which it is possible to attach a pipe, tube or similar item to be connected. The pipe connector flange preferably surrounds the outlet opening so that the entire cross-section of the outlet opening is in fluid communication with the interior of a pipe to be connected. According to the invention, however, the pipe connector flange is preferably disposed non-concentrically with the outlet opening at the outer wall of the housing, but offset therefrom. An offset is thus produced between the outlet opening and the pipeline which is to be connected to the pipe connector flange. This offset can serve advantageously as a barrier for solids and can prevent these from being washed back into the outlet opening, or between the rotary lobe vanes and the housing, or between two rotary lobe vanes engaging with each other, after leaving the outlet opening. In this way, the sensitivity of the rotary lobe pump to foreign matter, and the costs for repair and maintenance of the rotary lobe pump can be further reduced, and the service life of the rotary lobe pump further increased.
It is advantageous, more specifically, when the lower discharge ramp of the outlet opening slopes more strongly than the upper discharge ramp, when the rotary lobe pump is in an operating position in which the rotational axes of the two rotary lobes are horizontally oriented and arranged vertically one above the other, such that a vertical offset is produced at the lower discharge ramp of the outlet opening in relation to a pipeline to be connected, i.e., that the lower discharge ramp of the outlet opening is disposed at the outer housing wall above a lower wall of a pipeline to be connected. In this way, the offset between the outlet opening and the pipeline to be connected forms an obstruction for solids that have left the outlet opening and which are located, due to force of gravity or due to currents or vortices in the medium, in the lower region of a pipeline to be connected, with the result that the solids cannot reach the outlet opening again, or only with difficulty.
The invention is preferably developed by the housing having a base frame comprising two receptacles and two flanges which can be replaceably mounted in the receptacles, one of the two flanges being embodied as the outlet flange surrounding the outlet port and the other of the two flanges is embodied as the inlet flange surrounding the inlet port. The invention is preferably also developed by the two flanges and/or the two receptacles being embodied in such a way that each of the two flanges can be mounted in the one receptacle and also in the other receptacle.
Due to the different configurations of the inlet opening and the outlet opening, an optimal feeding direction of the rotary lobe pump from the inlet opening to the outlet opening is defined. A reversed feeding direction is possible with this configuration of inlet and outlet opening, but it is disadvantageous because there is a higher risk of solids becoming jammed between the rotary lobe vanes and the housing, or between two rotary lobe vanes engaging with each other. In some applications, however, it is advantageous and desirable that the feeding direction of a rotary lobe pump can be changed, for example when media must be conveyed in different directions or in order to clear blockages. In the development according to the invention, it is therefore provided that the housing be modular in structure, comprising a base frame which has two recesses or receptacles into each of which a flange can be inserted. One flange preferably surrounds the inlet opening or the outlet opening and also, if necessary, the pipe connector flange surrounding the outlet opening. It is particularly preferred that the two flanges and/or the two receptacles have a geometry that allows each of the two flanges to be mounted in any of the two receptacles. When both flanges are detachably mountable in the receptacles, the optimal feeding direction can be reversed by swapping the two flanges. In order to ensure simple handling and thus fast and simple reversal of the feeding direction, it is particularly preferred when the flanges are mounted in the recesses by means of quick-release fasteners.
In this way, the advantages of an asymmetric configuration of inlet and outlet openings can be combined with the advantages of a reversible feeding direction.
The invention is preferably developed by the two receptacles being embodied in such a way that they mirror each other in a plane of symmetry running through the base frame. This development is particularly preferred because a mirrored configuration of the receptacles and preferably also a mirrored configuration of the external geometry of the flanges allows the flanges to be swapped in a particularly simple manner.
The invention is preferably developed by the outlet opening having at least one mobile adjuster member that can be adjusted between a first and a second position in such a way that the feeding direction when the adjuster member is in the first position is opposite the feeding direction when the adjuster member is in the second position. The invention is also preferably developed by the inlet opening having at least one mobile adjuster member that can be adjusted between a first and a second position in such a way that the feeding direction when the adjuster member is in the first position is opposite the feeding direction when the adjuster member is in the second position.
It is thus preferred in this development of the invention that the geometry of the outlet and inlet opening be variable in design, alternatively or in addition to a development of the invention with flanges that can be swappingly mounted. It is particularly preferred when the outlet opening can be modified by the at least one mobile adjuster element in such a way that it has the geometry of the inlet opening when the adjuster element is in the second position. It is also preferred when the inlet opening can be modified by the at least one mobile adjuster element in such a way that it has the geometry of the outlet opening when the adjuster element is in the second position. In this way, the feeding direction of the rotary lobe pump can be reversed by moving the adjuster element or adjuster elements from a first position to the second position. This allows the feeding direction to be reversed in a particularly simple manner, as it is not necessary to replace any components. The advantages of an asymmetric configuration of the inlet opening and outlet opening can be combined simultaneously with the advantages of a reversible feeding direction.
The invention is preferably developed by the adjuster member of the outlet opening having a pressure contact surface embodied in such a way that the adjuster member is disposed in the first position under a first pressure of the medium at the outlet opening and in the second position under a second pressure of the medium at the outlet opening, the second pressure preferably being an underpressure. Another preferred development provides a pressure sensor which is configured to detect the pressure of the medium at the outlet opening and which is coupled to the adjuster element of the outlet opening in such a way that the adjuster element is disposed in the first position under a first pressure of the medium at the outlet opening and in a second position under a second pressure of the medium at the outlet opening. The invention is also preferably developed by the adjuster member of the inlet opening having a pressure contact surface embodied in such a way that the adjuster member is disposed in the first position under a first pressure of the medium at the inlet opening and in the second position under a second pressure of the medium at the inlet opening, the second pressure preferably being an underpressure. Another preferred development provides a pressure sensor which is configured to detect the pressure of the medium at the inlet opening and which is coupled to the adjuster element of the inlet opening in such a way that the adjuster element is disposed in the second position under a first pressure of the medium at the inlet opening and in the first position under a second pressure of the medium at the inlet opening. It is particularly preferred in this regard when the pressure sensor for detecting the pressure of the medium at the inlet opening is identical to the pressure sensor for detecting the pressure of the medium at the outlet opening.
These developments according to the invention advantageously utilize the different pressures in the medium prevailing on the inlet side and the outlet side of a rotary lobe pump. On the inlet side, there is a prevailing underpressure or suction in the medium, referred to as the second pressure, whereas on the outlet side there is a prevailing positive pressure referred to as the first pressure. When the feeding direction is reversed, these pressure conditions also change accordingly. By activating the adjuster element or the adjuster elements according to these pressure conditions, it is possible to ensure that the geometry of the inlet opening and the outlet opening are adapted in a simple manner to the feeding direction. The adjuster element or the adjuster elements can be coupled to the pressure of the medium mechanically or via one or more sensors.
The invention is preferably developed by at least one of the adjuster members being coupled to at least one of the rotary lobes in such a way that the adjuster member or the adjuster members is/are disposed in the first position when the rotary lobe turns in a first direction of rotation and is/are disposed in the second position when the rotary lobe turns in a second direction of rotation.
Another way of activating the adjuster element or adjuster elements is by coupling it or them with the direction of rotation of one or both of the two rotary lobes, as provided in this development of the invention. When the feeding direction is reversed, the direction of rotation of the rotary lobes also changes, thus allowing the geometry of the inlet and outlet opening to be changed according to the direction of rotation and thus to the feeding direction when the adjuster element or adjuster elements are coupled, preferably mechanically or by sensors, to the direction of rotation.
The invention is preferably developed by at least one of the adjuster members being coupled in such a way to a switching mechanism for setting the feeding direction of the rotary lobe pump that the adjuster member or the adjuster members is/are disposed in the first position when the rotary lobe pump turns in a first feeding direction and in the second position when the rotary lobe pump turns in a second feeding direction.
Another way of activating the adjuster element or the adjuster elements is the coupling, provided in this development of the invention, to the switching device of the rotary lobe pump, with which the feeding direction can be reversed. By coupling the adjuster element or the adjuster elements mechanically or via sensors to the switch position of the switching device, the geometry of the inlet and outlet opening can be made directly dependent on the feeding direction.
BRIEF DESCRIPTION OF THE FIGURES
A preferred embodiment of the invention shall now be described with reference to the Figures, in which:
FIG. 1 : shows a cross-section through a rotary lobe pump according to the prior art,
FIG. 2 : shows a cross-section through a first embodiment of a rotary lobe pump according to the invention and
FIG. 3 : shows a cross-section through a second embodiment of a rotary lobe pump according to the invention.
DETAILED DESCRIPTION
FIG. 1 shows the prior art, comprising a rotary lobe pump 100 with two rotary lobes 110 , 120 and a housing 130 . The two rotary lobes 110 , 120 each have a rotational axis 111 , 121 and four rotary lobe vanes 112 , 122 . Housing 130 has an inner wall 131 enclosing sections of the outer peripheries of rotary lobes 110 , 120 , an outer wall 132 defining the outer periphery of the rotary lobe pump and feet 133 , 134 . Housing 130 has one inlet opening 150 and one outlet opening 140 . Outlet opening 140 is surrounded by a pipe connector flange 143 to which a pipeline 160 with an upper wall 161 , a lower wall 162 and a middle axis 163 is connected. The middle axis 163 of pipeline 160 is the same as the middle axis of pipe connector flange 143 . Inlet opening 150 is also surrounded by another pipe connector flange 153 , to which another pipeline 170 with an upper wall 171 , a lower wall 172 and a middle axis 173 is connected.
To convey a medium in the direction from inlet opening 150 to outlet opening 140 , rotary lobes 110 , 120 turn in the direction of rotation shown by arrows 113 , 123 . Inlet opening 150 and outlet opening 140 each taper towards inner wall 131 of the housing and are embodied with mirror symmetry in relation to mirror plane SF. Between inner wall 131 and outer wall 132 , the inlet and outlet openings form side faces 141 , 142 , 151 , 152 .
The enclosed angle of the housing, in both the region of the inlet opening and the region of the outlet opening, is α+Δα, i.e., the inner wall of the housing encloses a respective section of the outer periphery of a rotary lobe of (2×α)+(2×αΔ). Such a mirror-symmetrical configuration of the inlet opening and the outlet opening is advantageous with regard to a possible switching of the feeding direction of the rotary lobe pump. However, this solution according to the prior art needs to be improved with regard to sensitivity to foreign matter, frequency of shut-downs, pressure loss, wear and tear, service life and costs of repair and maintenance.
FIGS. 2 and 3 show two embodiments of rotary lobe pumps according to certain embodiments the invention. Components with the same or similar functions are marked with the same reference signs plus 100 ( FIG. 2 ) and plus 200 ( FIG. 3 ) compared to FIG. 1 . In the following, the main focus is on the differences between the rotary lobe pump according to the invention, as shown in FIGS. 2 and 3 , and the rotary lobe pump known from the prior art, as shown in FIG. 1 , and on the differences between the two variants of the invention as shown in FIGS. 2 and 3 . FIGS. 2A and 2B illustrate dimensions identifying a first flow length at the housing inlet and a second flow length at the housing outlet, as well as a first minimum length between rotational axes of the two rotary lobes. The figures also illustrate a second length at the outer surface of the inlet opening, a third length at the inner surface of the inlet opening, a fourth length at the inner surface of the outlet opening, and a fifth length at the outer surface of the outlet opening. FIG. 2 illustrates that the third length is less than the first minimum length between axes of the two rotary lobes and a fourth length at the inner surface of the outlet opening. FIG. 2 also illustrates that each of the inlet and the outlet have a continuous decreasing convergence that occurs along the entire first flow length and the second flow length.
FIGS. 2 and 3 differ from the prior art solution shown in FIG. 1 by the configuration of outlet openings 240 , 340 . In both the variants shown in FIGS. 2 and 3 , outlet openings 240 , 340 have the same design. FIGS. 2 and 3 differ in that inlet opening 250 in FIG. 2 is the same as inlet opening 150 according to the prior art in FIG. 1 , whereas FIG. 3 shows an inlet opening 350 that differs not only from the prior art in FIG. 1 but also from the variant of the invention shown in FIG. 2 .
The different configurations of inlet openings 250 , 350 in FIGS. 2-4 is made clear, in particular, by the different inflow characteristics of the medium, as schematically represented by the arrows in the region of inlet openings 250 , 350 . Due to the inlet opening 250 tapering in the direction of inner wall 231 of housing 230 in FIG. 2 , the medium is guided in the middle between the two rotary lobes 210 , 220 . In the non-tapering inlet opening 350 in FIG. 3 and FIG. 4 , in contrast, the medium flows across the entire cross-section of inlet opening 350 towards a wider region of the two rotary lobes 310 , 320 .
In accordance with the invention, outlet openings 240 , 340 in FIGS. 2-4 taper in the feeding direction, i.e. in the direction from the inner wall 231 , 331 to the outer wall 232 , 332 of housing 230 , 330 . The circular paths on which the tips of rotary lobe vanes 212 , 222 , 312 , 322 turn define the outer peripheries 214 , 224 , 314 , 324 of the rotary lobes, which partially intersect. The enclosed angle of inner wall 231 , 331 of the housing is β−Δβ above and below the outlet side of the rotary lobe pump. The enlargement of outlet opening 240 , 340 on discharge is therefore greater in a direction running parallel to the plane of rotational axes 211 , 221 , 311 , 321 and perpendicularly to rotational axis 211 , 221 , 311 , 321 than the distance between rotational axes 211 , 221 , 311 , 321 .
The lower side face or discharge ramp 242 , 342 slopes more strongly than the upper side face 241 , 241 . This is realized, in the variant of the invention shown in FIGS. 2 and 3 , by the upper discharge ramp 241 , 341 of outlet opening 240 , 340 ending at the outer wall 232 , 332 of housing 230 , 330 at the height of the rotational axis 211 , 311 of the upper rotary lobe 210 , 310 , and by the lower discharge ramp 242 , 342 of outlet opening 240 , 340 not ending at the outer wall 232 , 332 of housing 230 , 330 until an angle of β+Δρ is reached. A vertical offset V thus ensues between outlet opening 240 , 340 and the lower wall 262 , 362 of the connected pipeline 260 , 360 , said offset serving as a barrier for the solids a, b. The dot-dash arrows show the tangential direction in which the solids are flushed out of the cavities between the rotary lobe vanes. These tangential directions point away from the rotary lobe vanes of the respective opposite rotary lobe. As can be seen from the dotted arrows, the paths of motion of the solids a conveyed by the lower rotary lobe 220 , 320 extend in a curve from outlet opening 240 , 340 into the interior of the connected pipeline 260 , 360 . The paths of motion of the solids b conveyed by the upper rotary lobes 210 , 310 likewise extend in a curve from outlet opening 240 , 340 into the interior of connected pipeline 260 , 360 . These paths of motion of the solids, achieved by the outlet openings being configured in accordance with the invention, substantially reduce clogging with the solids in the rotary lobe pump and thus lead to improvements with regard to sensitivity to foreign matter, frequency of shut-downs, pressure loss, wear and tear, service life and costs of repair and maintenance of the rotary lobe pump according to the invention, in comparison with the prior art.
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Embodiments provide a rotary lobe pump for conveying a fluid medium containing solids. Two rotary lobes have rotational axes that are spaced apart from each other a minimum length distance. A housing enclosing the two rotary lobes has an inlet opening and an outlet opening, each with a continuously decreasing convergence and defined lengths.
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FIELD OF USE OF THE INVENTION
The present invention relates to the field of systems for monitoring the pressure and temperature of vehicle tires and, in particular, to adaptations enabling the electronic measurement housing containing the sensor to be attached to the rim.
DESCRIPTION OF THE PRIOR ART
One of the current clamping solutions consists in using a banding attaching the electronic housing by passing beneath the housing or through slots made therein for passing the strap and for closing same over the circumference of the rim. Such a solution has the disadvantage of sidewalls of the tire being applied against the housing when the tire is mounted onto or removed from the rim.
Subjecting the housing to such stresses can have such consequences as:
the banding being torn away, damage to the housing, damage to the inner wall of the tire during said tearing away, the appearance of bulges in the damaged portions, etc.
For example, it has been observed that, during mounting of a heavy goods vehicle tire, a sensor housing attached to the rim with a strap or stainless steel banding having a flat section (12 to 1.2 mm) cannot move axially parallel to the axis of the wheel by more than 40 mm. As a matter of fact, this travel corresponds to the plastic deformation limit of the strap. Therefore, once this movement is reached during the mounting and removal stages, the consequence of the strap being deformed is that:
the housing is no longer urged against the rim and rotates freely or, more commonly the strap breaks.
Such a movement is largely possible due to the fact that the center portion of the rim commonly reaches 80 mm.
Even though the aforementioned technical problems are not pointed out therein, this configuration is found in US Patent 2004/0118195, which describes an apparatus for monitoring the parameters of a tire mounted on a vehicle wheel including a sensor configured to be installed inside the tire. The sensor is attached to the wheel rim so as to prevent same from being exposed to the liquid present in said tire. According to one embodiment, the sensor is attached to the wheel by means of two straps or bandings which extend around a circumferential surface of the rim and which are associated with a pedestal base coupled to said sensor.
The fact that the sensor or the housing containing the sensor is associated with a pedestal base does indeed increase the height of the assembly and therefore the obstacle that same comprises during the mounting and removal stages.
In addition, the volumes of the assembled pedestal base and housing assume a concave peripheral shape which becomes an area for holding the bead of the tire, a hold which will end when the connection is broken, either between the pedestal base and the housing or the banding or bandings, as described above.
The use of bandings also not only has the disadvantage of not being the most heavy-duty solution, but likewise that of not being adaptable to tapered rim profiles. As a matter of fact, by definition, a band has a single diameter on both edges thereof, which therefore does not allow the adaptation of same to a variation in diameter.
SUMMARY OF PREFERRED EMBODIMENTS OF THE INVENTION
Based on these established facts, the applicant conducted research aiming to solve this problem of the electronic housing attachment means being torn away.
This research resulted in the design and production of a particularly successful attachment device for an electronic housing, which enables the disadvantages of the prior art to be eliminated while at the same time reducing the costs for such a device.
The preferred embodiments of the invention likewise relate to the electronic housing containing the sensor, which is adapted to such an attachment device.
According to the preferred embodiments of the invention, the device for clamping an electronic pressure and/or temperature measurement housing onto a rim inside of a tire, consists of at least one cable which, making at least one turn around the rim, and urging the housing against the surface of the rim, forms a resilient connection allowing axial movement of the housing on the rim and thereby preventing said housing from bearing the stress of the tire during the mounting and removal stages.
The use of a cable makes it possible to combine both the function of a positional hold on the rim and that of enabling said housing from adopting an avoidance behavior with regard to the stresses exerted by the edges of the tire during the mounting and removal stages. As a matter of fact, by inserting the housing between the loop formed by the cable and the surface of the rim, the attachment offered by tensioning the cable enables an optimized positional hold.
By proposing the housing to be urged by means of a cable, said housing will be able to move by sliding rotationally around the axis of the wheel, over the surface of the rim, so as to be in contact with the sidewall of the tire; the stress created by the latter tends to cause the housing to slide over the rim along the cable, so as to prevent any damage to the housing, the attachment cable thereof or the tire. The housing can slide along the cable and rotate with the cable.
The use of a cable guarantees improved resistance to the risk of breakage to which same is subjected when the housing held thereby is subjected to the pressure exerted by the tire walls during the mounting and removal stages. The bandings of the prior art which, by nature, have flat or at least rectangular profile attachment bands, are much more fragile than a cable.
The use of a cable which has a substantially circular profile has the advantage of making only tangential contact with the surface of the rim. This reduced contact surface, compared with that offered by a strap, facilitates the axial movement of the cable and therefore that of the housing.
Another technical effect offered by the solution of using a cable as a means for attaching the housing to the rim, relates to the inherent resiliency of the cable which, by reason of the material thereof, the number of wires comprising same and the twisting thereof, allows a percentage of elastic stretching. This possibility of stretching allows the housing to move by sliding axially over the surface of the rim until same comes to lean against a radial projection of the rim, whereby, if the edge of the tire is still in contact with the housing after the movement, it is no longer the housing and the cable which take on the stresses but the rim. An equivalent degree of resiliency cannot be obtained with a strap-type band of solid material. Thus, for example, the applicant's tests revealed that a stainless steel banding having a thickness of 1.2 mm had an elongation percentage within the elastic and linear range of 2.3%, whereas a 1.5-mm diameter cable likewise made of stainless steel had an elongation percentage of 4.4%.
Another advantage to such a solution, of course, lies in the low cost thereof as well as the implementability of same.
According to another feature, said cable goes around the rim twice and is connected to the two longitudinal edges of the housing. In addition to improved distribution of the clamping force exerted by the cable on the housing against the rim, the use of a single cable on two sides of the housing is particularly advantageous in that, when the axial action of the sidewall of the tire on the side of the housing has the effect of urging said housing against an arm of the U formed by the rim profile, the possible raising of one side of the housing will result in a more significant clamping of the other loop of the cable, thereby guaranteeing the positional hold thereof between the arms of the U (drop center) formed by the rim profile. Such a technical effect is enabled by the fact that, according to another particularly advantageous feature of the preferred embodiments of the invention, the loop or loops of the cable come to bear against the upper portion of said housing.
Whether by means of one or more loops, another advantage of the device is that of fitting to the profile (drop center) of the rims, whether cylindrical, as is often the case for steel rims, or tapered, as is often the case for aluminum rims. As a matter of fact, the resiliency and tensioning of the cable enables the loop diameter to be fitted exactly to the diameter of the rim profile. This adaptation constitutes a marked progress in comparison with the attachments of the prior art using banding or a strap or straps, which require a rim profile with a cylindrical portion corresponding to at least the width of the banding.
According to another feature, said cable is tensioned during the use thereof. In fact, the installation of said device for clamping a pressure and temperature sensor housing onto a vehicle rim is characterized in that it consists in using a steel cable which goes around the rim so as to urge said housing against the rim and in selecting the characteristics of the cable and the tensioning value thereof during use of same, so that it is capable of elastically deforming when the housing moves, which movement takes place during the mounting and removal stages, via contact of the tire walls with said housing.
According to another particularly advantageous feature of the preferred embodiments of the invention, the device comprises a connection module which ensures the attachment of the housing to the cable and the connection of the two ends of the cable.
According to another particularly advantageous feature of the preferred embodiments of the invention, the device comprises a connection module which ensures the attachment of the housing to the cable, an attachment which, starting from a certain stress threshold, is designed to tend towards breakage, thereby releasing the housing to slide on the cable.
Such an attachment guarantees that the housing moves beneath the cable in the event of high stress. This voluntary breakage does not call into question the urging exerted by the cable, but renders the position of the housing random relative to the cable. According to one embodiment, said connection module bears against a projection coming from the housing, a projection having a voluntarily weakened section or one made of a fusible material capable of being broken starting with a certain stress threshold.
The preferred embodiments of the invention likewise relate to an electronic housing which is adapted to the clamping device described above, i.e., to a cable attachment. To accomplish this, the body of the housing, which matches the shape of the rim, is provided with two grooves into which the loop or loops of the cable are threaded. Alternatively or in addition to said grooves, preformed channels in the housing can provide the same function.
The preferred embodiments of the invention likewise relate to a housing, characterized in that it includes a concave shape on the outer surface thereof for accommodating said connection module, from which a radial projection projects, against which said connection module comes to bear, and which is capable of breaking in the event that a high degree of stress is exerted on the housing.
The basic concepts of the preferred embodiments of the invention have been explained above in the most elementary form thereof, and other details and features will become more apparent upon reading the following description in connection with the appended drawings, which, for non-limiting illustrative purposes, provide an embodiment of an attachment device in accordance with the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram drawing of a partial exterior perspective view of the mounting of a housing on a rim, using an embodiment of a device in accordance with the invention,
FIG. 2 is a partial top view of said mounting,
FIG. 3 is a partial side view of said mounting,
FIG. 4 is an exterior perspective detail view of the connection module of the housing cable,
FIG. 5 is a diagram drawing of a side view of the mounting of said housing on a rim having a tapered profile.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As shown in the drawing of FIGS. 1 to 4 , the housing 100 containing the various sub-assemblies involved in measuring and transmitting the quantities, such as the temperature and pressure inside the tire (not shown), is urged against the cylindrical surface of the rim 200 by means of a cable 300 .
According to a preferred but non-limiting embodiment, said cable consists of a plurality of twisted stainless steel wires and has a diameter of 1.5 mm.
To that end, the housing 100 assumes a shape or is sufficiently flexible in order to match the cylindrical surface 210 of the rim 200 .
As shown in the drawing of FIG. 3 , the so-called “drop center” profile of the rim 200 forms a flared U at the bottom of which (cylindrical surface 210 ) said housing 100 is arranged.
By surrounding the housing on the rim, the cable 300 urges the housing 100 into the bottom of the U while forming two loops 310 and 320 around the rim 200 , which bear against the side edges of the housing 100 , as shown in the drawing of FIG. 2 .
To that end, said housing 100 includes two longitudinal side channels 110 and 120 on the upper surface thereof, into which the two loops 310 and 320 are threaded. According to the embodiment shown, these channels 110 and 120 are extended at the two ends thereof by grooves likewise provided in the housing.
The combination of these channels 110 and 120 and these grooves that have been preformed in the housing guarantee the connection of same to the cable 300 .
The size of the channels and grooves as well as the material of the housing 100 enable the cable 300 to slide for positioning purposes but also in order to enable the avoidance movement described below.
The resiliency of the cable 300 which, according to a preferred embodiment, is close to 4.4%, will enable the sidewall of the tire to axially carry away the housing 100 and to cause it to move in the direction of arrow F 1 or F 2 (see FIG. 3 ), over the cylindrical surface 210 of the rim 200 . Once the U-shaped edges of the profile have been reached, it is the rim 200 which will counter the stresses transmitted by the sidewalls of the tire.
The housing 100 has an insignificant length in comparison to the stress-transmitting area, which will cause same to:
exit the stress area and slide beneath the tire (beneath the smallest diameter of the sidewall of the tire) while resuming its initial position, and/or slide along the cable 300 on the cylindrical surface 210 , according to arrows F 3 or F 4 , as shown in the drawing of FIG. 2 .
Thus, the housing 100 and the device for attaching same to the rim 200 do not oppose the stresses of the tire but use said stresses in order to move the sensor housing, owing to the resiliency of the cable 300 and/or to the slideability either of the housing 100 along the attachment cables thereof or of the housing 100 and cable 300 around the rim 200 .
As shown in the drawing of FIG. 4 , a connection module 400 ensures that the housing 100 is held in position on the cable 300 . This connection module includes a body 410 accommodating a threaded rod 420 onto which a nut 430 is screwed. According to an embodiment not shown, said threaded rod 420 is drilled transversely so as to enable the end of the cable 300 to be threaded therethrough and to enable same to be clamped by tightening the nut 430 .
According to another embodiment not shown, the cable 300 is positioned between said body 410 and the nut 430 for clamping purposes.
As shown, the housing 100 includes a concave shape 130 on the upper surface thereof for accommodating the volume of said connection module 400 . According to an embodiment of the invention, a projection 131 projects radially from the bottom portion of said concave shape 130 , against which the body 410 of the connection module 400 comes to bear.
According to an embodiment of the invention, said projection 131 is dimensioned such that, if the housing 100 and/or the cable 300 are subjected to excessive stress, the projection 131 breaks and enables the connection module 400 to be disconnected from the housing 100 , thereby enabling same to slide along the surface of the rim 200 without interfering with the clamping function.
In order to simplify the device and according to the non-limiting embodiment shown, said connection module 400 likewise enables the two ends 330 and 340 of the cable 300 to be joined together.
According to another embodiment not shown, the body of the connection module is provided with a bore positioned over the projection of said housing.
FIG. 5 shows the advantages of the clamping device of an embodiment of the invention, as used for attachment to a tapered rim profile 200 ′, like that which may be found on aluminum rims. It is clearly apparent that the clamping offered by implementing two loops of a wire product such as the cable 300 ′ best enables the housing 100 ′ to be urged against the tapered surface 210 ′ of the rim 200 ′, despite the difference in diameter due to the taper. Such a technical result cannot be obtained by a banding attachment means using a band of material of which both ends cannot be joined together under good conditions. According to this embodiment, said cable 300 ′ clamps said housing 100 ′ by means of two loops 310 ′ and 320 ′ around the rim 200 ′, the loops bearing against the upper surface of the housing 100 , and the surface being provided with two grooves 110 ′ and 120 ′.
It is understood that the clamping device and the housing have just described and shown above with a view to disclosure rather than limitation. Of course, various arrangements, modifications and improvements may be made with regard to the above example, without thereby departing from the scope of the invention.
Thus, for example, during installation, the cable is tensioned (approximately 100 Newtons) with a cable puller type of tool, prior to the final locking of the cable 300 in unit 400 . This tensioning, combined with the elastic properties of the cable, enables the desired avoidance behavior to be obtained.
According to another embodiment not shown, the connection module 400 can be molded directly onto a cable end 300 and form an integral part thereof, in order to facilitate industrial applicability of an embodiment of the invention.
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A device for clamping an electronic pressure and/or temperature measurement housing onto a rim inside of a tire, comprises a cable including a plurality of twisted filaments. The cable makes a turn around the rim, and urges the housing against the surface of the rim, forming a resilient connection allowing axial movement of the housing on the rim, thereby preventing the housing from bearing a stress of the tire during mounting and removal stages.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 10/528,515, which has an assigned filing date of Oct. 26, 2005, which was the National Stage of International Application No. PCT/US2003/029302, filed Sep. 19, 2003, and which claims the benefit of U.S. Provisional Application No. 60/412,125, filed Sep. 19, 2002. This application is also a continuation-in-part of U.S. patent application Ser. No. 10/470,372, which has an assigned filing date of Jul. 25, 2003, which was the National Stage of International Application No. PCT/US02/03920, filed Jan. 28, 2002, and which claims the benefit of U.S. Provisional Application No. 60/264,877, filed Jan. 29, 2001.
BACKGROUND OF THE INVENTION
[0002] This invention relates to load indicating fasteners that are “thread-forming” (also referred to as “thread-rolling” or “self-tapping” fasteners), methods for making load indicating thread-forming fasteners, and methods for measuring the load in thread-forming fasteners.
[0003] Thread-forming fasteners are well known in many industries, such as in high-volume automotive assembly. Examples of such fasteners are described in U.S. Pat. No. 5,242,253 (Fulmer), issued Sep. 7, 1993, for example. Such fasteners are also marketed commercially, for example, by Reminc, Research Engineering and Manufacturing Inc., Middletown, R.I., USA, under the trademark “Taptite” and “Taptite 2000”, and a description of such fasteners can be found in their product literature, entitled “Taptite 2000 Thread Rolling Fasteners”.
[0004] The major advantage of thread-forming fasteners is that they can be installed directly into a drilled hole, eliminating the cost of tapping the hole. Additionally, the thread formed by a thread-forming fastener has very tight tolerance since it is formed by the fastener itself and therefore forms a better nut.
[0005] Although thread-forming fasteners have been used in numerous applications in the automotive and aerospace industries to reduce cost, such fasteners are generally restricted to non-critical or less-critical applications. The difficulty in controlling the tightening process prevents their use in critical applications.
[0006] The primary reason for this is that the thread-forming process requires torque, in addition to the tightening torque, and this thread-forming torque varies significantly with hole tolerance, material, friction conditions, etc. As a result, the precise tightening of a thread-forming fastener to a specified torque into a blind hole, where the thread is still being formed as the bolt is being tightened, will result in a 3 sigma load scatter of typically +/−50%, which is unacceptable in critical applications.
SUMMARY OF THE INVENTION
[0007] For some time, ultrasonics has been used to accurately measure the load in bolts. Initially, removable ultrasonic devices were the most commonly used. More recently, low-cost permanent ultrasonic transducers, which can be permanently attached to one end of the fastener, have come to be used. Permanent fasteners of this type are described, for example, in U.S. Pat. No. 4,846,001 (Kibblewhite), issued Jul. 11, 1989, U.S. Pat. No. 5,131,276 (Kibblewhite), issued Jul. 21, 1992, U.S. Provisional Patent Application No. 60/264,877 (Kibblewhite), filed Jan. 29, 2001, and International Application No. PCT/US02/03920 (Kibblewhite), filed May 17, 2002, the subject matter of which is incorporated by reference herein.
[0008] In accordance with the present invention, it has been determined that such ultrasonics can be mated with an otherwise conventional thread-forming fastener to provide a load indicating thread-forming fastener that can be used for precise and reliable assembly of critical bolted joints, such as those in automobile engines (e.g., cylinder heads, connecting rods, main bearings, etc.), drive trains, steering, brakes, suspensions, and a variety of other applications, including aerospace applications.
[0009] Steps can then be taken, using equipment and methods that are otherwise known and conventional, to accurately measure and control the load in the thread-forming fastener during tightening, and to inspect the load in the thread-forming fastener after assembly.
[0010] For further detail regarding preferred embodiments for implementing the improvements of the present invention, reference is made to the description which is provided below, together with the following illustrations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 shows an example of a typical load indicating thread-forming fastener which is produced in accordance with the present invention.
[0012] FIGS. 2 and 3 are graphs showing typical load and torque characteristics plotted against the angle of rotation of the load indicating thread-forming fastener of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0013] FIG. 1 shows a typical embodiment of a load indicating thread-forming fastener which is produced in accordance with the present invention. In this illustrative example, the load indicating thread-forming fastener has been implemented in conjunction with an otherwise conventional “Taptite” fastener, which is commercially available from Reminc, Research Engineering and Manufacturing Inc., Middletown, R.I., USA. It is to be understood, however, that this embodiment is shown only for purposes of illustration, and that the load indicating thread-forming fastener of the present invention can also be implemented using any of a variety of known and available load indicating devices, coupled or combined with any of a variety of known and available thread-forming fasteners.
[0014] In the illustrative embodiment of FIG. 1 , the load indicating thread-forming fastener 10 generally includes a fastener 12 (e.g., the above-mentioned “Taptite” fastener) and a permanent piezoelectric polymer film transducer 14 (e.g., of the type disclosed in the above-mentioned U.S. Pat. No. 4,864,001, issued to Kibblewhite) attached to one end. The fastener 12 includes a head 16 , which can be suitably engaged by a tool (not shown) for applying torque to the fastener 12 , and a thread-forming body portion 18 .
[0015] A suitable identifying element is applied to the thread-forming fastener which can be read and used to determine ultrasonic measurement parameters specific to the thread-forming fastener in order to provide more precise and more reliable load measurements by compensating for differences resulting from manufacturing variations in individual thread-forming fasteners.
[0016] For example, as disclosed in U.S. Provisional Patent Application No. 60/264,877 (Kibblewhite) and International Application No. PCT/US02/03920 (Kibblewhite), the transducer 14 can further include a permanent mark such as a two-dimensional high-density bar code (not shown) or some other encodable medium, applied to the top electrode 20 of the transducer 14 for purposes of facilitating subsequent steps taken to obtain an indication of tensile load, stress, elongation or other characteristic of the fastener 12 during a tightening operation, or at various other times during the service life of the fastener 12 , as will be discussed more fully below.
[0017] As an alternative, the permanent mark can be applied directly to the thread-forming fastener, and the ultrasonic transducer can then be applied on top of the mark in such a way that the mark can be detected through the transducer. As an example, the bar code can be marked on an end surface of the fastener and the ultrasonic transducer can then be provided on the surface with the bar code in such a manner that the bar code can be read through the transducer. In one such embodiment, the transducer layers are translucent or transparent, allowing the bar code to be read through the piezoelectric and conductive layers of the transducer. In another embodiment, the bar code is marked using an indentation technique, such as dot peening, so that the indentations are detectable, and the bar code is made readable, after application of the transducer.
[0018] As a further alternative, a non-volatile memory device can be applied to the thread-forming fastener for purposes of storing desired information. Such memory devices can be powered, written to and read from serially through a single input/output connection and an AC coupled return through the capacitance of the ultrasonic transducer. Such devices are capable of storing data such as unique identification, ultrasonic measurement parameters, tightening and inspection data for use in a manner similar to that of the above-described use of a permanent mark for the storage of information.
[0019] In one such embodiment, the previously described top electrode 20 is replaced with the non-volatile memory device, and portions of the top exposed surface of the memory device are made conductive by providing the surface with an electrical contact. This top conductive surface is then electrically connected to a conductive layer on the bottom of the memory device, adjacent to the active piezoelectric polymer film transducer 14 , to provide a suitable electrode for the ultrasonic transducer. The top conductive surface is also electrically connected to the non-volatile memory device for purposes of writing information to and reading information from the memory device.
[0020] In another embodiment, the foregoing non-volatile memory device can be a radio frequency identification (RFID) chip or tag coupled with the transducer 14 for purposes of storing desired information. This can be accomplished with known RFID devices, such as the MetalSentinel (13.56 MHz) device available from Interactive Mobile Systems, Inc., Port Townsend, Wash., USA, which are capable of storing data such as unique identification, ultrasonic measurement parameters, and tightening and inspection data.
[0021] In such an embodiment, the previously described top electrode 20 is replaced with the RFID device, and portions of the top exposed surface of the RFID device are made conductive by providing the exposed surface with an electrical contact. This top conductive surface is then electrically connected to a conductive layer on the bottom of the RFID device, adjacent to the active, piezoelectric polymer film transducer 14 , to provide a suitable electrode for the transducer 14 . The piezoelectric polymer film transducer 14 is an electrical insulator and further functions as an isolator for the antenna associated with the RFID device for purposes of RF transmission.
[0022] The size, shape and location of the conductive portions of the top exposed surface of the RFID device can vary to suit the particular RFID device which is used. For example, the conductive portions of the top exposed surface can be placed along the periphery of the RFID device, leaving the central portions of the top exposed surface open to accommodate the antenna normally associated with the RFID device. The conductive portions of the top exposed surface should preferably cover as much of the top surface of the RFID device as is possible, while leaving sufficient open space to accommodate the function of the antenna. The conductive layer on the bottom of the RFID device preferably covers the entire bottom surface, to maximize contact with the transducer 14 .
[0023] Various different couplings are used with RFID devices, including electromagnetic, capacitive and inductive couplings, with different coupling antennas. The antenna can be provided adjacent to non-conductive portions of the top exposed surface. Alternatively, the conductive portions of the top and bottom surfaces of the RFID device can be constructed in such a way as to function as the antenna for the transponder associated with the RFID device which is used. It will further be appreciated that non-contact inductive or capacitive couplings used for RFID transponder communication in the above described embodiments can also be used to couple the excitation signal to the ultrasonic transducer. Additionally, the RF communication frequency can be selected to correspond to a preferred ultrasonic transducer excitation frequency. This then eliminates the need for an electrically conductive top surface for electrical contact with the transducer for load measurement, allowing both the reading of information stored in the RFID device and the measurement of load to be performed even when the transducer is covered with paint or other protective coating.
[0024] As an example, the transducer 14 can be implemented using a thin piezoelectric polymer sensor (e.g., a 9 micron thick, polyvinylidene fluoride copolymer film, of the type manufactured by Measurement Specialties Inc., Valley Forge, Pa., USA) permanently, mechanically and acoustically attached to an end surface 22 of the fastener 12 . The top electrode 20 of the transducer 14 can be implemented as a thin metallic foil (e.g., an approximately 50 micron thick, type 316 , full-hard, dull or matte finished stainless steel) which has been treated to provide a black oxide finish, which is then preferably provided with a black oxide treatment to provide an extremely thin, durable, corrosion resistant and electrically conductive, black coating. A high-resolution bar code can be marked on the resulting surface by removing selected areas of the coating (e.g., by conventional laser ablation techniques), or by some other process, to provide a high contrast mark easily read with conventional, commercially available optical readers. As an alternative, a non-volatile memory device, such as an RFID device, can be applied to the transducer 14 to provide data storage which can similarly be read with conventional, commercially available readers.
[0025] It is again to be understood that such implementations are described only for purposes of illustration, and that any of a variety of transducer configurations can be used to implement the transducer 14 applied to the fastener 12 , as desired. For example, the ultrasonic transducer 14 can be implemented as an oriented piezoelectric thin film, vapor deposited directly on the head of the fastener 12 , as is described in U.S. Pat. No. 5,131,276 (Kibblewhite), issued Jul. 21, 1992. As a further alternative, the ultrasonic transducer 14 can be implemented as a piezoelectric polymer film, chemically grafted on the head of the fastener 12 , as is described in U.S. Provisional Patent Application No. 60/264,877 (Kibblewhite), filed Jan. 29, 2001, and International Application No. PCT/US02/03920 (Kibblewhite), filed May 17, 2002. It will be readily understood that other alternative implementations are also possible.
[0026] In the embodiment illustrated in FIG. 1 , the ultrasonic transducer 14 is permanently attached to the head 16 of the fastener 12 , as described in the above-referenced patents issued to Kibblewhite. An essentially flat, or spherically radiused surface 24 is provided on at least a portion of the threaded end of the fastener to provide an acoustically reflective surface to reflect the ultrasonic wave transmitted by the transducer back to the transducer. Load is then measured using standard, pulse-echo ultrasonic techniques, which are themselves known in the art and described, for example, in the above-referenced patents issued to Kibblewhite. Load control accuracies of +/−3% have been achieved when tightening thread-forming fasteners into blind holes during both the first and subsequent tightenings.
[0027] In an alternative embodiment, an essentially flat surface is provided on the head 16 of the thread-forming fastener 12 and a removable ultrasonic transducer is temporarily attached to the fastener for the purpose of making load measurements. The threaded end of the fastener 12 is identical to the previous embodiment with the permanent ultrasonic transducer.
[0028] In practice, heat is generated as a result of the thread-forming work that takes place during the thread-forming run-down stage of the installation of a thread-forming fastener. This results in a slight increase in temperature in both the fastener (the bolt) and the resulting joint. This increase in temperature can cause errors in the ultrasonic load measurements to be taken because of thermal expansion effects. For this reason, when using ultrasonics for inspecting the load in a fastener, it is usual to measure the temperature of the fastener or the joint in order to compensate for the effects of thermal expansion.
[0029] However, in conjunction with a thread-forming fastener, the average temperature increase due to the heat generated during thread-formation can not be measured directly during the installation process and is subject to variations in material, friction, and heat conduction properties of the joint components. Without compensation, this thermal effect can result in inaccuracies of load measurement on the order of 5% to 20%, depending on the bolt, the joint and the assembly process being used.
[0030] FIGS. 2 and 3 show typical load and torque characteristics plotted against the angle of rotation of a typical bolt. FIG. 2 shows the tightening curves for a typical through-hole application, in which the torque reduces after the thread is formed through the entire hole. FIG. 3 shows the tightening curves for a typical blind hole application, in which the thread is still being formed as the bolt is tightened.
[0031] Further in accordance with the present invention, more accurate load measurements in the thread-forming load indicating fasteners are provided by eliminating the effects of fastener heating resulting from the thread-forming process. This is achieved by measuring the load (or acoustic time-of-flight) value immediately prior to the load-inducing stage of the assembly process, and by using this measured value as the zero-load reading.
[0032] The load-inducing stage of the assembly process can be detected by any one of a variety of methods. For example, an increase in load above a predetermined threshold, a change in the increase in load with time, angle of rotation of the fastener or torque, an increase in torque above a predetermined threshold, or a change in the increase in torque with time, angle or load can be detected. Irrespective of the method used to detect the load-inducing stage of the assembly process, a new zero-load base measurement is taken as a value just prior to the load-inducing assembly stage by selecting or calculating a load measurement prior to the load-inducing stage. This can be achieved by selecting a load measurement corresponding to a fixed time or angle prior to the detection of the commencement of the load-inducing stage, for example. Alternatively, for through-hole applications, the end of the thread-forming phase can be detected by a reduction in torque. It is again to be understood that such methods are only illustrative, and that there are numerous other methods for determining the new zero-load base measurement prior to tightening, from load, time, torque and angle of rotation measurements recorded during assembly operations with hand and powered assembly tools.
[0033] The thermal effect of thread forming causes an apparent positive load value at zero load just prior to tightening. An alternative to zeroing the load (or time-of-flight measurement) is to add this load offset, measured prior to the load-inducing stage of the assembly process, to the target load (or target time-of-flight). The result is the same since the increase in measured load is the same.
[0034] Yet another alternative is to experimentally determine an average value of load error due to the thread forming and adjust the zero-load measurement or target tightening parameter to compensate for this effect using one of the above-described methods. This approach, however, does not compensate for variations with individual fasteners or joint components and is therefore presently considered less desirable.
[0035] The result is that, for the first time, ultrasonic load measurement technology can be used with thread-forming fasteners. Errors in load measurement resulting from the thermal effects of thread-forming can be compensated. This then results in accurate load measurement and tightening control of the thread-forming fasteners.
[0036] The above-described method of eliminating the effects of fastener heating resulting from the thread-forming process can also be used with other fastener assembly processes that generate heat prior to the load-inducing tightening stage. Thread-locking bolts and nuts, for example, are manufactured with a prevailing “locking” torque to prevent the fastener from loosening during service. Most often, the thread of either the bolt or nut has an irregular profile causing the threads to elastically deform slightly upon mating. Alternatively, the bolt or nut has an insert or patch of a soft material to provide the prevailing torque or resistance to loosening. The prevailing torque provided by these thread-locking features produces heating of the fastener during rundown in the same manner as the tapping torque does with a thread-forming fastener. Consequently, the above-described method for compensating for thermal-related errors in accordance with the present invention can be used with prevailing torque-locking fasteners to improve the accuracy of ultrasonic load measurement during assembly.
[0037] It will be understood that various changes in the details, materials and arrangement of parts which have been herein described and illustrated in order to explain the nature of this invention may be made by those skilled in the art within the principle and scope of the invention as expressed in the following claims.
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An ultrasonic load measurement transducer is mated with a thread-forming fastener to provide a load indicating thread-forming fastener that can be used for the precise and reliable assembly of critical bolted joints, such as those in the automobile and aerospace industries, among others. Steps can then be taken to accurately measure and control the load in the thread-forming fastener during tightening, and to inspect the load in the thread-forming fastener after assembly. A similar result can be achieved for a thread-locking fastener by mating an ultrasonic transducer with the thread-locking fastener assembly.
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BACKGROUND OF THE INVENTION
Cephalosporins having a ureido acyl side chain are disclosed in U.S. Pat. Nos. 3,673,183; 3,708,479, 3,833,568 and 3,860,591. Cephalosporins having various acyl side chains and a 7α-methoxy substituent are taught in various U.S. patents including U.S. Pat. Nos. 3,775,410; 3,780,031; 3,780,033; 3,780,034, 3,780,037; 3,843,641, etc.
Cephalosporins having an acylureido acyl side chain are disclosed in U.S. Pat. Nos. 3,687,949 and 3,925,368 and German Offenlegungsschrift Nos. 2,513,954 and 2,514,019. Our prior application Ser. No. 671,788, filed Mar. 30, 1976, discloses [[[(2,4-dioxo-1-imidazolidinyl)amino]carbonyl]amino]acetyl cephalosporin derivatives.
SUMMARY OF THE INVENTION
It has now been found that new [imidazolidinyl amino]carbonyl]amino]acetylcephalosporin derivatives having the formula ##STR4## have useful antimicrobial activity.
R represents hydrogen, lower alkyl, phenyl-lower alkyl, diphenyl-lower alkyl, tri(lower alkyl)silyl, trihaloethyl, a salt forming ion, or the group ##STR5## wherein R 5 is hydrogen or lower alkyl and R 6 is lower alkyl.
R 1 represents hydrogen or methoxy. The R 1 substituent is in the α-configuration as indicated by the broken lines ( ).
R 2 and R 3 each represents hydrogen or lower alkyl.
R 4 represents hydrogen, lower alkyl, cyclo-lower alkyl, cyclo-lower alkenyl, cyclo-lower alkadienyl, phenyl, phenyl-lower alkyl, substituted phenyl, substituted phenyl-lower alkyl, or certain heterocyclic groups.
X represents hydrogen, lower alkanoyloxy, certain heterothio groups, ##STR6##
When X is pyridinium or carbamoyl substituted pyridinium, the compounds can be structurally represented as having the formula ##STR7## wherein Z is hydrogen or carbamoyl.
DETAILED DESCRIPTION OF THE INVENTION
The various groups represented by the symbols have the meaning defined below and these definitions are retained throughout this specification.
The lower alkyl groups referred to throughout this specification include straight or branched chain hydrocarbon groups containing 1 to 8 carbon atoms, preferably 1 to 4 carbons and especially 1 or 2 carbons. Examples of the type of groups contemplated are methyl, ethyl, propyl, isopropyl, butyl, t-butyl, etc. The lower alkoxy groups (referred to below) include such lower alkyl groups attached to an oxygen, e.g., methoxy, ethoxy, propoxy, etc. The phenyl-lower alkyl and diphenyl-lower alkyl groups include such lower alkyl groups attached to a phenyl with the same preferred groups as above but especially benzyl, phenethyl and diphenylmethyl.
The cyclo-lower alkyl groups are alicyclic groups having 3 to 7 carbons in the ring, i.e., cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and cycloheptyl. The cyclolower alkenyl groups represent rings having 4 to 7 carbons with one double bond, i.e., cyclobutenyl, cyclopentenyl, cyclohexenyl, etc. The term cycloalkadienyl represents a ring having 6 or 7 carbons with two double bonds located at various positions such as 1,4-cyclohexadienyl which is especially preferred. The C 5 -C 6 alicyclics are preferred.
The substituted phenyl and substituted phenyl-lower alkyl groups include those having one or two substituents on the phenyl ring, e.g., halogen (preferably chlorine or bromine), lower alkyl (preferably C 1 -C 4 and especially methyl or ethyl), lower alkoxy (preferably C 1 -C 4 and especially methoxy or ethoxy), or hydroxy, e.g., 2-, 3- or 4-chlorophenyl, 2-, 3- or 4-bromobenzyl, 2-, 3- or 4-hydroxyphenyl, 3,5-dichlorophenyl, 2-, 3- or 4-methylphenyl, 2-, 3- or 4-ethoxyphenyl, etc. The 4-monosubstituted phenyl groups are preferred.
The salt forming ions represented by R are metal ions, e.g., aluminum, alkali metal ions such as sodium or potassium, alkaline earth metal ions such as calcium or magnesium, or amine salt ions, of which a number are known for this purpose, for example, phenyl-lower alkylamines, such as dibenzylamine, N,N-dibenzylethylenediamine, lower alkylamines such as methylamine, ethylamine, tri(lower alkyl) amine such as triethylamine, and N-lower alkylpiperidines such as N-ethylpiperidine. Sodium and potassium are the preferred salt forming ions.
The halogens are the four common halogens, of which chlorine and bromine are preferred. In the case of the trihaloethyl group represented by R, 2,2,2-trichloroethyl is preferred.
Trimethylsilyl is the preferred tri(lower alkyl)silyl group.
The heterocyclic groups represented by R 4 are 2-thienyl, 3-thienyl, 2-furyl, 3-furyl, 2-pyridyl, 3-pyridyl or 4-pyridyl. Also included within the meaning of R 4 are such heterocyclics having as a substituent R 9 which is halogen (preferably chlorine or bromine) or lower alkyl (preferably C 1 -C 4 and especially methyl or ethyl) substituent, i.e., 2-(4-chlorothienyl), 3-(4-methylthienyl), etc.
The lower alkanoyloxy groups are the acyl groups of the lower fatty acids having the formula ##STR8## preferably wherein lower alkyl is of 1 to 4 carbons, especially methyl.
The heterothio groups represented by X are ##STR9## wherein R 7 is hydrogen or lower alkyl (preferably C 1 -C 4 and especially methyl or ethyl) and R 8 is hydrogen, lower alkyl (preferably C 1 -C 4 and especially methyl or ethyl), methoxy, hydroxy or halogen (preferably chlorine). Especially preferred are the tetrazole group above wherein R 7 is methyl, the 1,3,4-thiadiazole group above wherein R 7 is methyl and the 4-carbamylpyridinium group.
The compounds of formula I wherein R 1 is hydrogen can be prepared by several methods. For example, an α-amino intermediate of the formula ##STR10## wherein X is hydrogen, lower alkanoyloxy, or heterothio can be reacted, preferably in the form of its trifluoroacetic acid salt, with an imidazolidine compound of the formula ##STR11## wherein R 2 and R 3 are as defined above and hal is chlorine or bromine to yield the compound of formula I wherein R 1 is hydrogen and X is hydrogen, lower alkanoyloxy or heterothio.
The α-amino intermediate of formula II can be prepared by various methods such as by acylating a 7-amino cephalosporin of the formula ##STR12## with a substituted α-amino acid of the formula ##STR13## wherein Y is a protecting group such as ##STR14## The α-amino protecting group is then removed by treating the resulting cephalosporin with trifluoroacetic acid and anisole. The α-amino compounds of formula II are taught in various U.S. patents as for example, U.S. Pat. Nos. 3,485,819; 3,507,861; 3,641,021; 3,796,801; 3,813,388; 3,821,207, etc.
Similarly, the 7α-methoxy compounds of formula I (R 1 is methoxy) wherein X is hydrogen, lower alkanoyloxy or heterothio can be prepared by reacting an α-amino intermediate of the formula ##STR15## preferably in the form of its trifluoroacetic acid salt with a compound of formula III or IV.
The 7α-methoxy intermediates of formula VII can be prepared in an analogous manner to the compound of formula II, i.e., by acylating a 7α-methyl-7β-aminocephalosporin of the formula ##STR16## with a substituted α-amino acid of formula VI followed by removal of the protecting group. The compounds of formula VIII are taught in U.S Pat. No. 3,897,424 and the preparation of the compound of formula VII by various other methods are taught in U.S. Pat. Nos. 3,775,410; 3,780,031; 3,780,033; 3,780,034; 3,780,037; 3,887,549, etc.
The compounds of formula I wherein R 1 is either hydrogen or methoxy and X is pyridinium or carbamoyl substituted pyridinium are prepared by reacting the compound of the formula ##STR17## with pyridine or carbamoyl substituted pyridine (e.g., isonicotinamide) in a polar solvent such as water and in the presence of a catalyst such as an alkali metal thiocyanate. U.S. Pat. No. 3,792,047 and German Offenlegungsschrift No. 2,234,280 both disclose methods for reacting a cephalosporin so as to replace an acetoxy group with a pyridinium group.
Also, the compounds of formula I wherein R 1 is either hydrogen or methoxy and X is heterothio can be prepared by reacting the compound of formula Ib with a mercaptan of the formula
hetero-S--H (IX)
or an alkali metal (preferably sodium) salt thereof of the formula
hetero-S-alkali metal (X)
methods for displacing the acetoxy group of a cephalosporin by a heterothio group are taught in various U.S. Pat. including U.S. Pat. Nos. 3,855,213; 3,890,309; 3,892,737, etc.
The compounds of formula I wherein R 3 is hydrogen or lower alkyl and X is hydrogen, acetoxy or heterothio can also be prepared by reacting a compound of the formula ##STR18## or a derivative thereof wherein the hydroxy group is replaced with a known activating group, e.g., acid chloride, mixed anhydride, activated ester, etc., with an ester, e.g., trimethylsilyl or diphenylmethyl ester, of the compound of formula V or VIII, optionally in the presence of dicyclohexylcarbodiimide. The resulting ester is then treated according to methods known in the art, e.g., with water or with trifluoroacetic acid and anisole to yield the corresponding compound of formula I wherein R is hydrogen.
The preferred starting material of formula III is prepared from a 1-amino-2-imidazolidinone of the formula ##STR19## which in turn is derived from a 2-imidazolidinone of the formula ##STR20## [utilizing the method described in J. Amer. Chem. Soc. 78, 5350 (1956)] as described in more detail in the examples.
The compounds of formula I wherein R is lower alkyl, phenyl-lower alkyl, trihaloethyl, diphenyl-lower alkyl or the acyloxymethyl group ##STR21## are obtained by reacting the 7-aminocephalosporin of formula V or VIII either before or after the acylation of the 7-aminosubstituent with one or two moles of a compound of the formula
halo-R (XIV)
or
R═N.sup.+ ═N.sup.- (XV)
wherein halo is preferably chlorine or bromine, in an inert solvent such as dimethylformamide, acetone, dioxane, benzene, or the like at about ambient temperature or below.
Similarly, the compounds of formula I wherein R is tri(lower alkyl)silyl are obtained by introducing such groups onto the cephalosporanic acid moiety either before or after the acylation reaction.
The carboxylate salts of the compound of formula I are formed by reacting the carboxyl group of the cephalosporanic acid moiety, i.e., R is hydrogen, with any of the salt forming ions described above.
Additional experimental details are found in the examples.
It will be appreciated that the compounds of formula I are optically active due to the presence of an asymmetric carbon atom represented as C* in the preceding formulas. By selection of the appropriate starting material it is possible to obtain the compounds of formula I as a mixture of optically active isomers or isolated as a single isomer. The various isomers as well as their mixtures are within the scope of this invention.
Preferred compounds of this invention are the acids and alkali metal salts of formula I (i.e., R is hydrogen, alkali metal, especially sodium or potassium, or diphenylmethyl); wherein X is hydrogen, lower alkanoyloxy, especially acetoxy, pyridinium, carbamoyl substituted pyridinium (particularly where the carbamoyl group is in the 4-position), 1-methyltetrazolylthio or 5-methyl-1,3,4-thiadiazolylthio; R 1 is hydrogen or methoxy, especially hydrogen; R 4 is cyclohexadienyl, phenyl, benzyl, phenethyl, substituted phenyl, benzyl or phenethyl wherein the substituent is on the phenyl ring and is one or two members selected from chloro, bromo, methyl, ethyl, methoxy, ethoxy and hydroxy or a substituted or unsubstituted heterocyclic selected from 2-thienyl,3-thienyl, 2-furyl,3-furyl,2-pyridyl,3-pyridyl and 4-pyridyl wherein the heterocyclic substituent is chloro,bromo,methyl or ethyl; R 2 and R 3 each is hydrogen. When R 3 is other than hydrogen, methyl is preferred.
Compounds of formula I wherein X is ##STR22## and R 2 , R 3 and R 4 are as defined above are preferred as both final products and intermediates.
The most preferred final compounds are the acids and alkali metal salts of formula I wherein R 4 is 2-thienyl, 3-thienyl, phenyl or 4-hydroxyphenyl; and X is heterothio, particularly wherein X is ##STR23##
The compounds of formula I have a broad spectrum of antibacterial activity against both gram positive and gram negative organisms such as Staphylococcus aureus, Salmonella schott muelleri, Pseudomonas aeruginosa, Proteus rettgeri, Escherichia coli, Enterobacter hafniae, Enterobacter cloacae, Klebsiella pneumoniae, Serratia mercescens, etc. They may be used as antibacterial agents in a prophylactic manner or to combat infections due to organisms such as those named above, and in general may be utilized in a manner similar to cephalothin and other cephalosporins. For example, a compound of formula I or a physiologically acceptable salt thereof may be used in various mammalian species such as mice, rats, dogs, etc., in an amount of about 1 to 100 mg./kg., daily, orally or parenterally, in single or two to four divided doses to treat infections of bacterial origin, e.g., a dosage of 5.0 mg./kg. in mice.
About 10 to 400 mg. of an acid compound of formula I or a physiologically acceptable salt thereof can be incorporated in an oral dosage form such as tablet, capsule or elixir or in an injectable form in a sterile aqueous vehicle. The substance is compounded with a physiologically acceptable vehicle, excipient, binder, preservative, stabilizer, flavor, etc., in a unit dosage form as called for by accepted pharmaceutical practice. The amount of active substance in these compositions or preparations is such that a suitable dosage in the range indicated is provided.
Illustrative of the adjuvants which may be incorporated in tablets, capsules and the like are the following: a binder such as gum tragacanth, acacia, corn starch or gelatin; an excipient such as dicalcium phosphate; a disintegrating agent such as corn starch, potato starch, alginic acid and the like; a lubricant such as magnesium stearate; a sweetening agent such as sucrose, lactose or saccharin; a flavoring agent such as peppermint, oil of wintergreen or cherry. When the dosage unit form is a capsule, it may contain in addition to materials of the above type a liquid carrier such as a fatty oil. Various other materials may be present as coatings or to otherwise modify the physical form of the dosage unit. For instance, tablets or capsules may be coated with shellac, sugar or both. A syrup or elixir may contain the active compound, sucrose as a sweetening agent, methyl and propyl parabens as preservatives, a dye and a flavoring such as cherry or orange flavor. Of course, any material used in preparing the dosage unit should be pharmaceutically pure and substantially non-toxic in the amounts employed.
Injectable compositions are prepared by dissolving or suspending the active substance in a sterile vehicle such as water for injection or a natural vegetable oil such as sesame oil, cottonseed oil, peanut oil, soybean oil or the like or a synthetic fatty vehicle such as ethyl oleate. Antioxidants, buffers, preservatives and the like may also be included. The material can also be prepared in the dry form for reconstitution with such vehicles.
The following examples are illustrative of the invention and constitute especially preferred embodiments. They also serve as models for the preparation of other members of the group which can be produced by suitable substitution of starting materials. All temperatures are in degrees celsius.
EXAMPLE 1
(a) D-2-[[[(4-Methoxyphenyl)methoxy]carbonyl]amino]-2-thiopheneacetic acid
74 g. of D-2-thienylglycine are dissolved in 940 ml. of water. 37.8 g. of magnesium oxide are added and to this resulting suspension a solution of 107.5 g. of p-methoxybenzyloxycarbonylazide in 940 ml. of dioxane is added with stirring. The mixture is stirred at room temperature for 24 hours. It is then filtered and the filtrate is extracted with 600 ml. of ether. The extract is discarded. The water in dioxane phase is layered over with 600 ml. of ethyl acetate, cooled to 5° and brought to pH 2 with 2N hydrochloric acid. The layers are separated and the aqueous layer is again extracted with 300 ml. of ethyl acetate. The combined ethyl acetate extracts are washed with water, dried with magnesium sulfate, filtered and concentrated. The oily residue crystallizes upon trituration with petroleum ether to yield 118 g. of D-2-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thiopheneacetic acid; m.p. 84°-94°; [α] 20 D : -69° (c=1, tetrahydrofuran).
(b) 7β-Amino-3-[[(1-methyl-1H-tetrazolyl-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
To a stirred suspension of 27.2 g. of 7-amino cephalosporanic acid (0.1 mole) in 150 ml. of acetone and 100 ml. of water at 0°-5° is added 50 ml. of 2N sodium hydroxide, with care being taken to keep the pH below 8.5. A solution of 12.7 g. (0.11 mole) of 1-methyl-5-mercapto-1H-tetrazole in 50 ml. of 2N sodium hudroxide is added, and the mixture is allowed to warm to room temperature. The stirred mixture is then maintained at 60° (internal temperature) under nitrogen for 3 hours at pH 7-7.5 by the periodic addition of dilute aqueous sodium hydroxide. The mixture is cooled in an ice-water bath, and while stirring, 3N HCl is added to adjust the pH to 3.9. Stirring is continued for 15 minutes, and the precipitate is collected by filtration, washed with water, and then acetone, and finally dried to give the desired product as a powder (18.4 g.).
(c) 7β-Amino-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester
A mixture of 16.4 g. (0.05 mole) of the acid product from part (b), 10.3 g. (0.054 mole) of p-toluenesulfonic acid monohydrate, 350 ml. of dioxane (dried by passage through basic alumina), and dry CH 3 OH is stirred at room temperature under nitrogen for 30 minutes. The clear solution is evaporated to a residue, and water and CH 3 OH are removed by four evaporations of 100 ml. quantities of dioxane. Fresh dioxane (300 ml.) is then added to the residue followed by a solution of crystalline diphenyldiazomethane (19.4 g., 0.01 mole) in 150 ml. of dry dimethoxyethane. The mixture is initially shaken vigorously for 10-15 minutes and then stirred at room temperature for 3 hours. Methanol (25 ml.) is added, and the red solution is stirred until it has turned yellow-orange. The solvents are removed in vacuo, and the residue is treated with 400 ml. of CH 2 Cl 2 and a solution of 20 g. of K 2 HPO 4 in 250 ml. of water. The CH 2 Cl 2 layer is washed with water and saturated NaCl, and finally dried (MgSO 4 ) to give a residue after removal of the solvent in vacuo. Treatment of the residue with Et 2 O gives a solid (27 g.). Column chromatography of this solid on silica gel by elution with CHCl 3 and then EtOAc-CHCl 3 (4:1) provides the desired product as a residue (12.9 g.). Treatment with EtOAc then provides 8.0 g. of the desired product as a pale yellow powder.
(d) 7β-[[D-[[[ (4-Methoxyphenyl)methoxy]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester
46.2 g. of 7β-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester from part (c) are dissolved in 550 ml. of anhydrous methylene chloride. 550 ml. of tetrahydrofuran and 36 g. of D-2-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thiopheneacetic acid, from part (a), are added. The reaction solution is cooled to 0° and a solution of 22.5 g. of dicyclohexylcarbodiimide in 150 ml. of anhydrous tetrahydrofuran is added dropwise over the course of 30 minutes. The mixture is then stirred for 90 minutes at 0° and finally 120 minutes at room temperature. The precipitated dicyclohexylurea (21 g.) is filtered off under suction and the filtrate is concentrated. The residue is taken up in a mixture of 1000 ml. of ethyl acetate and 400 ml. of tetrahydrofuran, filtered and the filtrate is washed first with sodium bicarbonate solution and then with water. This is then dried with magnesium sulfate, treated with activated carbon, filtered and the filtrate is then concentrated slowly under vacuum to a small volume. After standing overnight in the refrigerator, the precipitated crystals are filtered under suction to obtain 63.1 g. of 7β-[[D-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(1-methyl-1H-tetrazol-5-yl)thio[methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester, m.p. 130°-131° (dec.). [α] 20 D -117° (c = 1, tetrahydrofuran).
(e) 7β-[D-2-Amino-2-(2-thienyl)acetamido]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]-oct- 2-ene-2-carboxylic acid, trifluoroacetic acid salt (1:1)
62 g. of the diphenylmethyl ester product from part (d) are added to 300 ml. of anisole with stirring. The mixture is cooled to 0° and 750 ml. of trifluoroacetic acid are added slowly. The mixture is stirred for 10 minutes at 0° and the anisole is evaporated at 0.1 mm. of Hg and 35° bath temperature. The residue is treated with 250 ml. of petroleum ether, then 350 ml. of ether, stirred for 1 hour, and filtered with suction to yield 46.4 g. of 7β-[D-2-amino-2-(2-thienyl)acetamido]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt (1:1); m.p. 138°-139° (dec.).
EXAMPLE 2
(a) L-2-[[[(4-Methoxyphenyl)methoxy]carbonyl]amino]-2-thiopheneacetic acid
L-2-Thienylglycine and p-methoxybenzyloxycarbonylazide are reacted according to the procedure of Example 1 (a) to yield L-2-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thiopheneacetic acid; m.p. 97°-98°; [α] D 25 +68° (c = 1, tetrahydrofuran).
(b) 7β-[[L-[[[(4-Methoxyphenyl)methoxy]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester
4.6 g. of L-2-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thiopheneacetic acid from part (a) and 5.9 g. of 7β-amino-3-[[(1-methyl-1H-tetrazol-5yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester from Example 1(c) are reacted according to the procedure of Example 1(d) to yield 8.4 g. of 7β-[[L-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester which after concentration and treating with ether is obtained in amorphous form.
(c) 7β-[L-2-Amino-2-(2-thienyl)acetamido]-3-[[(-1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt (1:1)
1.6 g. of the diphenylmethyl ester product from part (b) are treated with trifluoroacetic acid and anisole according to the procedure of Example 1 (e) to yield 1.1 g. of 7β-[L-2-amino-2-(2-thienyl)acetamido]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene carboxylic acid, trifluoroacetic acid salt (1:1); m.p. 127°-131° (dec.).
EXAMPLE 3
(a) D-2-[[[(4-Methoxyphenyl)methoxy]carbonyl]amino]phenyl acetic acid
D-2-phenylglycine and p-methoxybenzyloxycarbonylazide are reacted according to the procedure of Example 1 (a) to yield D-2-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]phenylacetic acid.
(b) 7β-[[D-[[[(4-Methoxyphenyl)methoxy]carbonyl]amino]phenylacetyl]amino]-3-[[(1-methyl-1H-tetrazol -5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester
12 g. (0.025 mole) of 7β-amino-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester from Example 1 (c) and 7.7 g. (0.025 mole) of D-2-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]phenylacetic acid from part (a) are reacted in the presence of 6.2 g. (0.025 mole) of dicyclohexylcarbodiimide according to the procedure of Example 1 (d) to yield 16 g. of light beige 7β-[[D-[[[4-methoxyphenyl)methoxy]carbonyl]amino]phenylacetyl]amino]-3-[[(1-methyl-1H-tetrazol-5-yl)thiomethyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester, m.p. 147° (dec.)
(c) 7β-[D-2-Amino-2-phenylacetamido[-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt (1:1)
16 g. of the diphenylmethyl ester product from part (b) are treated with trifluoroacetic acid and anisole according to the procedure of Example 1 (e) to yield 10.1 g. of 7β-[D-2-amino-2-phenylacetamido]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.9]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt (1:1); m.p. 128°-130° (dec.).
EXAMPLE 4
(a) 7β-Methoxy-7β-[[DL-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester
2.41 g. (0.0075 mole) of DL-2-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thiopheneacetic acid (prepared according to the procedure of Example 1 (a) is dissolved in 50 ml. of dry methylene chloride, the solution is cooled in an ice bath to 0°-5°, and 0.969 g. (0.0075 mole) of diisopropylethylamine and isobutylchloroformate are added to the cold solution. After 10 minutes, 3.28 g. (0.00625 mole) of 7β-amino-7α-methoxy-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl[-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester is added to the reaction mixture and the ice bath is removed. Following 3 hours of stirring at room temperature, a second portion of mixed anhydride is prepared in a separate flask using the procedure described above. This solution is added to the reaction mixture and after 4.5 hours another batch of mixed anhydride prepared using half the quantities set forth above is added to the main reaction mixture. Stirring is continued at room temperature for 12 hours and the reaction mixture is then diluted with methylene chloride and washed with water, saturated aqueous sodium bicarbonate solution, and water. The organic layer is dried over sodium sulfate and the solvent is removed in vacuo to yield a foam. This crude product is chromatographed on silica gel (200 g., 60-200 mesh) and the desired product is eluted with 9:1 and 4:1 methylene chloride: ethyl acetate. The oily product is precipitated as a powder from a methylene chloride-ether mixture and dried over phosphorus pentoxide in vacuo to yield 3.81 g. of 7α-methoxy-7β-[[DL-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester.
Alternatively, the same compound can be obtained by the following procedure:
129 mg. (0.4 mmole) of DL-2-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thiopheneacetic acid is dissolved in 2 ml. of anhydrous methylene chloride and 47 mg. (0.2 mmole) of dicyclohexylcarbodiimide is added. The mixture is stirred for 15 minutes at room temperature during which time colorless dicyclohexylurea crystallizes. The suspension is directly filtered into a stirred solution of 77 mg. (0.147 mmole) of 7β-amino-7α-methoxy-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester in 1 ml. of methylene chloride. After stirring at room temperature for 19 hours, the mixture is diluted with methylene chloride, washed with ph 7.4 buffer, and dried over sodium sulfate. Removal of solvent under reduced pressure yields a crude oil which is chromatographed on preparative thin layer chromatography silica gel plates developed in a 4:1 chloroform:ethyl acetate mixture. The desired product (58 mg.) is isolated as an oil.
(b) 7α-Methoxy-7β-[DL-2-amino-2-(2-thienyl)acetamido]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt
The diphenylmethyl ester product from part (a) is reacted with trifluoroacetic acid in the presence of anisole according to the procedure of Example 1 (e) to yield 7α-methoxy-7β-[DL-2-amino-2-(2-thienyl)acetamido]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt.
EXAMPLE 5
1-[(Phenylmethylene)amino]-2-imidazolidinone
63 g. (0.73 mol.) of 2-imidazolidinone are dissolved in 2 liters of 2N sulfuric acid, the solution is cooled to 3°-6° and 50.5 g. (0.73 mol.) of sodium nitrite are added in small amounts over a period of 15 minutes. The solution is stirred for 11/2 hours at 3°-6°. 110 g. (1.68 mol.) of zinc dust are added in small amounts over a period of 1 hour so that the temperature does not rise above 20°. At first the zinc dust goes quickly and completely into solution. The mixture is stirred for 30 minutes at 3°-6° and 60 minutes at room temperature. The undissolved zinc is filtered off and 70 g. (0.66 mol.) of benzaldehyde in 700 ml. of ethanol are added to the filtrate. After about 5 minutes, 1-[(phenylmethylene]amino]-2-imidazolidinone begins to crystallize. The mixture is stirred overnight at 5°-10°, then filtered under suction. The product is recrystallized from ethanol, yield 79.3 g.; m.p. 201°-206°.
EXAMPLE 6
1-Amino-2-imidazolidinone
A mixtureof 120 ml. of concentrated hydrochloric acid and 120 ml. of water are heated to boiling. 15 g. of 1-[(phenylmethylene)amino]-2-imidazolidinone are added and the benzaldehyde which forms is rapidly distilled off. After 30 minutes, the distillation is discontinued and the clear solution is evaporated to dryness. The solid residue is triturated with ethanol to obtain 1-amino-2-imidazolidinone hydrochloride, yield 9.2 g.; m.p. 175°-179° (dec.).
The free base is obtained by admixing 8.8 g. of the hydrochloride with 185 ml. of methanol and 32 ml. of sodium methylate solution and refluxing the mixture for 15 minutes. It is filtered while hot and the filtrate is evaporated to dryness. The residue, 1-amino-2-imidazolidinone, crystallizes on trituration with ether. After dissolving with ethanol, filtering, concentrating and triturating with petroleum ether several times, 6.9 g. of product are obtained, m.p. 65°-69°.
EXAMPLE 7
1-(Chlorocarbonylamino)-2-oxoimidazolidine
1.01 g. (0.01 mol.) of 1-amino-2-imidazolidinone are dissolved in 20 ml. of anhydrous tetrahydrofuran and 20 ml. of a 1M solution of phosgene in toluene are added at 0°. The solution is stirred overnight at room temperature. The almost clear solution is filtered and evaporated to dryness. The 1-(chlorocarbonylamino)-2-oxoimidazolidine is obtained as an oily residue which is used without further purification.
EXAMPLE 8
3-[[(1-Methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-7β-[[D-[[[(2-oxo-1-imidazolidinyl]amino]carbonyl]amino]-2-thienylacetyl]amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
1.74 g. (0.003 mol.) of 7β-[D-[2-amino-2-thienylacetyl]amino]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo -5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt, are suspended in 24 ml. of acetonitrile and 3 ml. of bis(trimethylsilyl)acetamide are added. As soon as the solution becomes clear, there are added 6 ml. of 1,2-propylene oxide, and a solution of 0.005 mol. of 1-(chlorocarbonylamino)-2-oxoimidazolidine in anhydrous tetrahydrofuran. The mixture is stirred for 30 minutes at 0° then three hours at room temperature. 50 ml. of water are added, the mixture is stirred for 5 minutes and then extracted three times with ethyl acetate. The ethyl acetate extracts are washed with water, dried with magnesium sulfate and concentrated under vacuum. The residue is triturated with ether and filtered under suction to obtain 1.2 g. of 3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo- 7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, m.p. 180° (dec.).
The sodium salt is produced by bringing the acid obtained above its solution with an equivalent proportion of aqueous sodium bicarbonate solution and freeze drying the solution, m.p. 208°-215° (dec.).
EXAMPLE 9
(2-Oxo-1-imidazolidinyl)carbamothioic Acid, S-Phenyl Ester
3.2 ml. of (phenylthio)carbonyl chloride are dissolved in 30 ml. of dioxane and a solution of 2.63 g. of 1-amino-2-imidazolidinone in a mixture of 10 ml. of dioxane and 10 ml. of water is added. 2N sodium hydroxide solution is added dropwise at room temperature so that the pH is about 7.5-8.0. About 15 ml. of 2N sodium hydroxide are required. The dioxane is then distilled off. An oil separates which crystallizes after a short while to give 3.2 g. of (2-oxo-1-imidazolidinyl)carbamothioic acid, S-phenyl ester, m.p. 154°-159° (after recrystallization from ethyl acetate).
EXAMPLE 10
3-[[(1-Methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-7β-[[D-[[[(2-oxo-1-imidazolidinyl]amino]carbonyl]amino]-2-thienylacetyl]amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
1.16 g. (0.002 mol.) of 7β-[D-[2-amino-2-thienylacetyl]amino]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt, and 0.82 ml. (0.006 mol.) of triethylamine are dissolved in 10 ml. of anhydrous dioxane and 0.55 g. (0.0023 mol.) of (2-oxo-1-imidazolidinyl) carbamothioic acid, S-phenyl ester are added. The solution is stirred for 6 hours at room temperature. Ether is then added and the triethylamine salt precipitates. This salt is dissolved in water, filtered and acidified with 2N hydrochloric acid. The precipitate, 3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, is isolated, yield 1.0 g.
EXAMPLE 11
3-[(Acetyloxy)methyl]-7β-[[[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
By susbtituting 3-[(acetyloxy)methyl]-7β-[D-[2-amino-2-phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt for the starting material in Example 8, 3-[(acetyloxy)methyl]-7β-[[[[[(2-oxo-1-imidazolidinyl)amino]-8-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid and its sodium salt are obtained.
EXAMPLE 12
3-[[4-(Aminocarbonyl)pyridinio]methyl]-8-oxo-7β-[[[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]phenylacetyl]amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid inner salt
A mixture of 0.455 g. of 3-[(acetyloxy)methyl]-7β-[[[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, sodium salt, 0.146 g. of 4-pyridinecarboxamide, 1.92 g. of potassium thiocyanate and 1.2 ml. of water are heated at 50° for 24 hours. A chromatography column is filled with 30 g. of ion exchange resin (Amberlite XAD-2). 20 g. of a paste of the same ion exchange resin is admixed with the reaction mixture, stirred for 30 minutes and the mixture is poured into the column. The column is eluted with 750 ml. of water, then with a mixture of water and methanol (8:2). The eluate is collected in 10 ml. portions. Fractions 95-120 are concentrated and freeze dried to obtain 85 mg. of 3-[[4-(aminocarbonyl)pyridinio]methyl]-8-oxo-7β-[[[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]phenylacetyl]amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, inner salt.
EXAMPLE 13
7β-[[DL-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-7α-methoxy-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
By substituting the 7α-methoxy-7β-[DL-2-amino-2-(2-thienyl)acetamido]-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt of Example 4b in the procedure of Example 8, 7β-[[DL-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-7α-methoxy-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid and its sodium salt are obtained.
EXAMPLE 14
(a) 3-[(Acetyloxy)methyl]-7α-methoxy-7β-[[DL-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester
DL-2-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thiopheneacetic acid and 3-[(acetyloxy)methyl]-7α-methoxy-7β-amino-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester are reacted according to the first procedure in Example 4 (a) to yield 3-[(acetyloxy)methyl]-7α-methoxy-7β-[[DL-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester.
(b) 3-[(Acetyloxy)methyl]-7α-methoxy-7β-[DL-2-amino-2-(2-thienyl)acetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt (1:1)
The diphenylmethyl ester product from part (a) is reacted with trifluoroacetic acid in the presence of anisole according to the procedure of Example 1 (e) to yield 3-[(acetyloxy)methyl]-7α-methoxy-7β-[DL-2-amino-2-(2-thienyl)acetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt (1:1).
(c) 3-[(Acetyloxy)methyl]-7α-methoxy-7β-[[DL-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, sodium salt
The trifluoroacetic acid salt product from part (b) is treated with the (2-oxo-1-imidazolidinyl)carbamothioic acid, s-phenyl ester from Example 9 according to the procedure of Example 10 to yield 3-[(acetyloxy)methyl]-7α-methoxy-7β-[[DL-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid.
An equimolar solution of this compound and sodium bicarbonate is lyophilized to yield 3-[(acetyloxy)methyl-7α-methoxy-7β-[[DL-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, sodium salt.
(d) 7α-Methoxy-7β-[[DL-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridinio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
An aqueous mixture of the sodium salt product of part (c), 4-pyridinecarboxamide, and potassium thiocyanate is reacted according to the procedure of Example 12 to yield 7α-methoxy-7β-[[DL-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridinio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid.
EXAMPLE 15
3-[(Acetyloxy)methyl]-7β-[[DL-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
By substituting 3-[(acetyloxymethyl]-7β-[[DL-[2-thienylacetylamino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, trifluoroacetic acid salt for the starting material in Example 8, 3-[(acetyloxy)methyl]-7β-[[DL-[[[2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid and sodium salt are obtained.
EXAMPLE 16
7β-[[DL-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(1-oxo-2-pyridinyl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
0.003 mole of 3-[(acetyloxy)methyl]-7β-[[DL-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, sodium salt from Example 15 and 0.004 mole of 2-mercaptopyridine, 1-oxide, sodium salt are dissolved in 15 ml. of water and heated overnight at 50°. The reaction mixture is then diluted with water, filtered, and the clear solution is adjusted to pH 2 by the addition of 2N hydrochloric acid. The resulting precipitate is filtered under suction to obtain 7β-[[DL-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(1-oxo-2-pyridinyl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid.
Following the same procedure but employing 3-[(acetyloxy)methyl]-7β-[[L-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, sodium salt, there is obtained the corresponding final product in the L-form.
EXAMPLE 17
7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino-2-thienylacetyl]amino]-3-[[(1-oxopyridazin-3-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
3-[(Acetyloxy)methyl]-7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, sodium salt is dissolved in a mixture of acetone:water (1:1). 1-Oxopyridazine-3-thiol, sodium salt is added under nitrogen and the solution is heated for several hours at 60°. The solution is diluted with 150 ml. of water and acidified to pH 5 by the addition of 2N hydrochloric acid while cooling. A precipitate forms which is filtered under suction to yield 7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(1-oxopyridazin-3-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid.
EXAMPLES 18-26
Following the procedure of Example 17 but substituting for the 1-oxopyridazine-3-thiol one of the following:
2-oxopyridazine-3-thiol
6-methyl-1-oxopyridazine-3-thiol
6-methoxy-1-oxopyridazine-3-thiol
6-t-butyl-2-oxopyridazine-3-thiol
6-ethyl-2-oxopyridazine-3-thiol
6-hydroxy-1-oxopyridazine-3-thiol
6-hydroxy-2-oxopyridazine-3-thiol
6-chloro-1-oxopyridazine-3-thiol
6-chloro-2-oxopyridazine-3-thiol
there is obtained, respectively:
7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(2-oxopyridazin-3-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid;
7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(6-methyl-1-oxopyridazin-3yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid;
7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(6-methoxy-1-oxopyridazin-3-yl]thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid;
7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(6-t-butyl-2-oxopyridazin-3-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid;
7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(6-ethyl-2-oxopyridazin-3-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid;
7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(6-hydroxy-1-oxopyridazin-3-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid;
7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(6-hydroxy-2-oxopyridazin-3-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid;
7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(6-chloro-1-oxopyridazin-3-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid;
7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-3-[[(6-chloro-2-oxopyridazin-3-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, respectively.
Similarly, by substituting 3-[(acetyloxy)methyl]-7α-methoxy-7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, sodium salt for the 3-[(acetyloxy)methyl]-7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, sodium salt in the foregoing procedure and utilizing each of the named thiols, the corresponding final products having a 7α-methoxy group are obtained.
The following additional compounds are produced by the procedure of Examples 7 and 8. The 1-amino-2-oxo-1-imidazolidine of formula A below, having the substituents R 2 and R 3 in the table, is converted to the chlorocarbonylamino derivative of formula B as in Example 7 then this intermediate is made to react with the intermediate of formula C below, having the substituents R, R 4 and X in the table, as in Example 8 to obtain the product of formula D, having the substituents in the table.
__________________________________________________________________________ ##STR24## ##STR25## ##STR26## ##STR27##A B C DExampleR.sub.2 R.sub.3 R.sub.4 R.sub.3 R.sub.2 R X__________________________________________________________________________27 CH.sub.3 H ##STR28## H CH.sub.3 t-C.sub.4 H.sub.9 ##STR29##28 H H ##STR30## H H ##STR31## ##STR32##29 H H ##STR33## H H ##STR34## ##STR35##30 H H ##STR36## H H CH.sub.2 CCl.sub.3 ##STR37##31 C.sub.2 H.sub.5 CH.sub.3 ##STR38## CH.sub.3 C.sub.2 H.sub.5 ##STR39## ##STR40##32 H C.sub.2 H.sub.5 ##STR41## C.sub.2 H.sub.5 H ##STR42## ##STR43##33 H H ##STR44## H H H H34 H t-C.sub.4 H.sub.9 ##STR45## t-C.sub.4 H.sub.9 H H ##STR46##35 CH.sub.3 CH.sub.3 ##STR47## CH.sub.3 CH.sub.3 H ##STR48##36 H H ##STR49## H H C.sub.2 H.sub.5 ##STR50##37 H H ##STR51## H H H ##STR52##38 H H ##STR53## H H t-C.sub.4 H.sub.9 ##STR54##39 H H ##STR55## H H H ##STR56##40 H H ##STR57## H H H ##STR58##41 CH.sub.3 H H H CH.sub.3 ##STR59## ##STR60##42 H H ##STR61## H H H ##STR62##43 H H C.sub.2 H.sub.5 H H t-C.sub.4 H.sub.9 ##STR63##44 H CH.sub.3 ##STR64## CH.sub.3 H ##STR65## ##STR66##45 H H ##STR67## H H ##STR68## ##STR69##46 H H ##STR70## H H H H47 H H ##STR71## H H H ##STR72##48 H H ##STR73## H H ##STR74## ##STR75##49 C.sub.4 H.sub.9 H ##STR76## H C.sub.4 H.sub.9 ##STR77## ##STR78##50 H H ##STR79## H H t-C.sub.4 H.sub.9 ##STR80##51 H H ##STR81## H H ##STR82## ##STR83##52 H H ##STR84## H H ##STR85## ##STR86##53 CH.sub.3 H ##STR87## H CH.sub.3 H ##STR88##54 H H ##STR89## H H H ##STR90##55 H CH.sub.3 ##STR91## CH.sub.3 H CH.sub.2CCl.sub.3 ##STR92##56 H H ##STR93## H H ##STR94## ##STR95##57 H H ##STR96## H H t-C.sub.4 H.sub.9 ##STR97##58 H H ##STR98## H H H ##STR99##59 H H ##STR100## H H ##STR101## ##STR102##60 H H ##STR103## H H ##STR104## ##STR105##61 H H ##STR106## H H ##STR107## ##STR108##62 H H ##STR109## H H H ##STR110##63 H H ##STR111## H H H ##STR112##64 H H ##STR113## H H Na ##STR114##65 H H ##STR115## H CH.sub.3 ##STR116## ##STR117##66 H H ##STR118## H H ##STR119## ##STR120##67 H H ##STR121## H H ##STR122## ##STR123##68 H H ##STR124## H H ##STR125## ##STR126##69 H H ##STR127## H H Si(CH.sub.3).sub.3 ##STR128##__________________________________________________________________________
The following additional compounds are also produced by the procedure of Examples 7 and 8. The chlorocarbonyl derivative of formula E below (derived as in Example 7), having the substituents R 2 , R 3 and R 4 in the table, is made to react with the 7-aminocephalosporanic acid derivative of formula F below as in Example 8 to obtain the product of formula G.
__________________________________________________________________________ ##STR129## ##STR130## ##STR131##(E) (F) (G)__________________________________________________________________________Example R.sub.2 R.sub.3 R.sub.4 R X__________________________________________________________________________70 H H ##STR132## t-C.sub.4 H.sub.9 ##STR133##71 H H ##STR134## ##STR135## ##STR136##72 H CH.sub.3 ##STR137## H ##STR138##73 H H ##STR139## CH.sub.2 CCl.sub.3 ##STR140##74 H H ##STR141## ##STR142## ##STR143##75 H C.sub.2 H.sub.5 ##STR144## ##STR145## ##STR146##76 H H ##STR147## t-C.sub.4 H.sub.9 H77 C.sub.2 H.sub.5 H ##STR148## ##STR149## ##STR150##78 H H ##STR151## ##STR152## ##STR153##79 H H ##STR154## CH.sub.2 CCl.sub.3 ##STR155##80 H H ##STR156## ##STR157## ##STR158##81 H H ##STR159## C.sub.2 H.sub.5 ##STR160##82 H H ##STR161## H ##STR162##83 H H ##STR163## t-C.sub.4 H.sub.9 ##STR164##84 H H ##STR165## ##STR166## ##STR167##85 H CH.sub.3 ##STR168## K ##STR169##86 H H H ##STR170## ##STR171##87 H H C.sub.2 H.sub.5 t-C.sub.4 H.sub.9 ##STR172##88 H H ##STR173## ##STR174## ##STR175##89 H H ##STR176## ##STR177## ##STR178##90 H H ##STR179## ##STR180## ##STR181##91 H H ##STR182## ##STR183## ##STR184##92 H H ##STR185## ##STR186## H93 H H ##STR187## H H94 H H ##STR188## t-C.sub.4 H.sub.9 ##STR189##95 CH.sub.3 H ##STR190## ##STR191## ##STR192##96 H H ##STR193## ##STR194## ##STR195##97 H H ##STR196## CH.sub.2CCl.sub.3 ##STR197##98 H H ##STR198## ##STR199## ##STR200##99 H H ##STR201## t-C.sub.4 H.sub.9 ##STR202##100 H H ##STR203## ##STR204## ##STR205##101 H H ##STR206## ##STR207## ##STR208##102 H CH.sub.3 ##STR209## ##STR210## ##STR211##103 H H ##STR212## H ##STR213##104 CH.sub.3 CH.sub.3 ##STR214## ##STR215## ##STR216##105 H H ##STR217## H ##STR218##106 H H ##STR219## ##STR220## ##STR221##107 H H ##STR222## ##STR223## ##STR224##108 H H ##STR225## ##STR226## ##STR227##109 H H ##STR228## Si(CH.sub.3).sub.3 ##STR229##__________________________________________________________________________
EXAMPLE 110
(a) D-α-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]-amino]-2-thiopheneacetic acid
3.14 g. (0.02 mol.) of D-α-amino-2-thiophene acetic acid are suspended in 60 ml. of acetonitrile and 15.0 ml. of bis(trimethylsilyl)acetamide are added. The suspension is stirred until a clear solution of the trimethylsilyl ester results. 40.0 ml. of propylene oxide are added and then a solution of 3.55 g. (0.02 mol.) of 1-(chlorocarbonylamino)-2-oxoimidazolidine in 80 ml. of anhydrous acetonitrile is added dropwise, then stirred at room temperature overnight. The solvent is evaporated in vacuum, water is added to the oily residue, neutralized with sodium bicarbonate and again concentrated. The solid residue is triturated with ether and filtered under suction. After drying, 10 ml. of 2N hydrochloric acid is added to the residue. After a short time, D-α-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thiopheneacetic acid crystallizes, which is purified by recrystallization from water.
(b) 3-[(Acetyloxy)methyl]-7β-[[D-[[[(2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[ 4.2.0]oct-2-ene-2-carboxylic acid
The product of part (a) is reacted with 7-amino cephalosporanic acid to obtain 3-[(acetyloxy)methyl]-7β-[D-[[[2-oxo-1-imidazolidinyl)amino]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid.
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[[[Imidazolidinyl amino]carbonyl]amino]acetylcephalosporin derivatives having the formula ##STR1## wherein R is hydrogen, lower alkyl, phenyl-lower alkyl, diphenyl-lower alkyl, tri(lower alkyl)silyl, trihaloethyl, a salt forming ion, or the group ##STR2## R 1 is hydrogen or methoxy; R 2 , R 3 and R 5 each is hydrogen or lower alkyl; R 4 is hydrogen, lower alkyl, cyclo-lower alkyl, cyclo-lower alkenyl, cyclo-lower alkadienyl, phenyl, phenyl-lower alkyl, substituted phenyl, substituted phenyl-lower alkyl, or certain heterocyclic groups; R 6 is lower alkyl; and X is hydrogen, lower alkanoyloxy, ##STR3## or certain heterothio groups; are useful as antibacterial agents.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present patent application is related to and claims the priority benefit of U.S. Provisional Patent Application Ser. No. 62/170,718, filed Jun. 4, 2015, the contents of which is hereby incorporated by reference in its entirety into this disclosure.
TECHNICAL FIELD
[0002] The present application relates to particle trapping and sensing systems, and more specifically, to systems which sense or trap particles within a liquid solution.
BACKGROUND
[0003] Various systems are known which allow isolating or sensing of particle or analyte concentration within a liquid solution. Such systems are used in many applications, such as sensing water quality or the presence of contaminants in biological samples. One prior art approach utilizes holographic optical tweezers in which a high power laser beam is split into several separate beams, with each beam having a fraction of the total power. The beams are then used to attract or repel particles of a certain type. However the throughput for such an approach is unacceptably low and the system is very costly due to the expense of adequate high power laser sources. Therefore, improvements are needed in the field.
SUMMARY
[0004] The present disclosure provides a particle sensing system which includes a plurality of micro-lenses which focus light from an unfocused or loosely focused light source onto a corresponding plurality of focus regions on a surface containing plasmonic structures. The absorption of light by the plasmonic structures in the focus regions results in heat dissipation in the plasmonic structures and consequently increases surface temperature in the focus regions. When an electrical field is applied to a sample fluid in contact with the surface, multiple electrothermal flows are induced in the fluid which rapidly transport suspended particles to the focus regions on the surface. The particles can then be captured and/or sensed. Because there are hundreds or even thousands of trapping sites (focus regions) on a single device, throughput is vastly increased when compared to prior art systems. The required power is also reduced, as the device may be activated by a low power and inexpensive light source.
[0005] According to one aspect, a particle sensing system is provided, comprising a first substrate having a first conductive layer on a first side of the first substrate, and a plurality of microlenses mounted to the first conductive layer. A second substrate having a second conductive layer faces the first conductive layer, with the second conductive layer having a plurality of light absorbing plasmonic structures. At least one channel separates the first and second conductive layers and configured to hold a liquid sample. The microlenses are configured to create a plurality of focus regions on the second conductive layer when light is directed through the microlenses.
[0006] According to another aspect, a particle sensing system is provided, comprising a first substrate having a first conductive layer on a first side of the first substrate, and a plurality of microlenses mounted to a second side of the substrate, with the first conductive layer having a plurality of light absorbing plasmonic structures. A second substrate having a second conductive layer faces the first conductive layer. At least one channel separates the first and second conductive layers and is configured to hold a liquid sample. The microlenses are configured to create a plurality of focus regions on the first conductive layer when light is directed through the microlenses, through the substrate and onto the first conductive layer.
[0007] According to another aspect, a method of concentrating particles in a liquid sample is provided, comprising directing light through a plurality of microlenses to create a corresponding plurality of focus regions on a first conductive layer of a first substrate, with the first conductive layer comprising a plurality of plasmonic structures; and applying a voltage across the first conductive layer and a second conductive layer of a second substrate, the first and second conductive layers separated by a channel containing the liquid sample, with the voltage selected to cause a predetermined particle type to be attracted to the plasmonic structures in the focus regions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] In the following description and drawings, identical reference numerals have been used, where possible, to designate identical features that are common to the drawings.
[0009] FIG. 1 is a side-view schematic diagram of a particle sensing system utilizing microlenses according to one embodiment.
[0010] FIG. 2 is a side-view schematic diagram of a particle sensing system utilizing microlenses according to another embodiment.
[0011] FIG. 3 is a top-view schematic diagram of microchannels through which a sample solution is directed according to one embodiment.
[0012] The attached drawings are for purposes of illustration and are not necessarily to scale.
DETAILED DESCRIPTION
[0013] For the purposes of promoting an understanding of the principles of the present disclosure, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of this disclosure is thereby intended.
[0014] FIG. 1 shows a side view of a sensing system 100 according to one embodiment. The system 100 may be implemented as a lab-on-a-chip device, although other forms may be used. As shown, the system 100 includes a first substrate 4 which has an electrically conducting layer 8 (collectively indicated as member 7 ) attached on an upper side as shown. In one embodiment, microlenses 1 are attached to the conducting layer 8 . However, the microlenses 1 may alternatively be mounted on a dielectric layer which is deposited on the electrically conductive layer 8 , with the dielectric layer separating the conductive layer 8 and the microlenses 1 . A second substrate 2 also has a conducting layer 10 (collectively indicated as member 6 ) mounted to a bottom side facing the microlenses 1 . In certain embodiments, the conducting layer 10 may comprise both an electrically conducting layer and layer comprising an array of plasmonic nanostructures. The distance between the faces of the microlenses 1 and the bottom surface 3 of the conducting layer 10 is preferably chosen to be the focal length of the microlenses 1 . An alternating current (AC) source 15 is connected to the conducting layers 8 and 10 as shown.
[0015] The first and second substrates 4 and 2 may comprise a material through which light can pass, such as glass or sapphire, to allow light from the source 5 to be directed through the microlenses 1 . The conductive layers 8 and 10 may comprise an electrically conductive material, such as metal or metal alloy.
[0016] The microlenses 1 may comprise planar metasurface lens or dielectric solid immersion microlenses. Other lens forms may also be used. An unfocussed or collimated light source 5 projects light through the microlenses 1 and focuses the light as spots onto multiple regions 9 as shown. The light source 5 may comprise a common low power source, such as a laser pointer, table lamp, or the like.
[0017] The regions 9 contain plasmonic components and are formed as arrays of plasmonic nanostructures, continuous metal film, or a combination of both. Because the conducting layer 10 is positioned at a distance from the microlenses 1 which is approximately equal to the focal length of the microlenses 1 , the focused light on the plasmonic components in the regions 9 are heated to form hotspots (each region 9 becomes a hotspot). The number of microlenses 1 in the path of the light source 5 will determine the number of corresponding hotspots (regions 9 ) created, assuming the regions 9 are spaced sufficiently far apart.
[0018] In certain embodiments, the plasmonic components in the regions 9 may comprise resonant plasmonic components, which will increase the heating effect due to efficient absorption and through the enhanced focusing of light at the regions 9 .
[0019] When the regions 9 are heated due to the absorption of focused light to form hotspots, the plasmonic components therein would transfer heat energy to the adjoining fluid medium 16 creating temperature gradients in the fluid 16 . The temperature gradients also result in a gradient in the fluid 16 electrical conductivity and permittivity. This in turn creates a net charge density in the fluid. An AC field is then applied by source 15 to cause electrothermal flow in the fluid. According to one embodiment, the AC electric field frequency chosen to below a critical frequency at which suspended particles in the fluid 16 will be attracted to and become trapped on the surface of the plasmonic components in the regions 9 . In certain embodiments, the AC electric field frequency is chosen to be in the range of 1 KHz to 200 KHz, although other frequencies may be used.
[0020] Furthermore, in certain embodiments, the temperature gradient established in the adjoining fluid medium can induce gradients in the density of the fluid to produce buoyancy-driven fluid convection. Even while the AC field and light illumination are ON, both the electrothermal flow and buoyancy-driven fluid convection will be superimposed. Thus, as the AC field is turned OFF, the agglomerated particles can still remain trapped while the laser illumination is ON due to the induced buoyancy-driven convection and thermophoresis. The trapped particles may be released by also turning OFF the light illumination.
[0021] In certain embodiments, the light focused by the microlenses 1 and absorbed by the plasmonic nanostructures at the focused regions 9 results in temperature gradients. The induced temperature gradients induces buoyancy-driven convection and thermophoresis for assembly of particles at multiple sites where the light spots have been focused.
[0022] Because there are hundreds or thousands of microlenses 1 in the path of the light source 5 , a corresponding number of trapping sites (regions 9 ) are created. Therefore, integrating microlenses 1 to cover the area over which the sample fluid 16 is present enables trapping of nearly all particles suspended in the fluid, even at very low concentrations.
[0023] In addition to serving as particle gathering or trapping sites, the plasmonic components in the regions 9 also serves as a sensing substrate for detection of the analyte. The disclosed embodiment therefore provides a self-contained system for both on-chip concentrating, sorting, and sensing of particles or analytes.
[0024] FIG. 2 shows a sensing system 200 according to another embodiment. The system 200 is similar to system 100 , but has microlenses 12 mounted on an outer or bottom side of the first substrate 17 as shown. The conducting layer 18 is similar to conducting layer 10 and similarly comprises a plurality of plasmonic structures. The second substrate/conducting layer 13 is similar to substrate/conducting layer 7 , with the sample fluid situated between the layer 13 and layer 18 . In the embodiment of FIG. 2 , the light source 5 is directed through the microlenses 12 , through the substrate 17 , and onto the regions 19 in the conducting layer 18 . The plasmonic structures in the regions 19 of the conducting layer 18 become hotspots and thereby create thermal gradients and particle trapping sites as described above with respect to system 100 . The plasmonic structures may also be separated from the conducting layer 18 by a dielecric layer.
[0025] In further embodiments, the system 100 or 200 may be used to separate particles of different sizes or types from the liquid sample. FIG. 3 shows a top view of one embodiment wherein a separation structure comprising a plurality of channels 21 , 22 , 23 is provided. Each channel includes a system 100 or 200 therein to form hotspots within the channel for trapping particles from the sample. The sample is first directed through channel 21 , with the AC source 15 frequency set to trap particles of a first size (e.g., the smaller particles) at the hotspots contained within the channel 21 .
[0026] In certain embodiments, the plasmonic components array on which the particles are concentrated in channel 21 may be functionalized to bind the concentrated target particles. For example, in embodiments wherein the concentrated particles are analytes, the plasmonic nanostructures may be functionalized with antibodies that can selectively bind to the target concentrated analyte. Other bio-molecules such as aptamers can also be used to functionalize the plasmonic nanostructure array to bind concentrated particles such as DNA molecules to the plasmonic nanostructure array.
[0027] After passing through channel 21 , the sample is then directed through channel 22 as indicated by the arrows and the AC source 15 frequency is adjusted to trap a second size of particles from the sample. The sample is then directed to channel 23 and the AC signal source is again adjusted to trap a third particle size. The process may be repeated with additional channels until all desired particles of interest have been trapped.
[0028] In a further embodiment, the plasmonic components in the conductive layer 10 or 18 may be selectively coated with polymers (e.g., loaded with biomolecules for selective functionalization) to change their local dielectric environment and resonance properties. For example, a solution containing polymer particles may be added to the above systems 100 or 200 . By applying a DC voltage (e.g., 5 volts) across the conducting layers 10 or 18 , the polymer particles will permanently stick to the plasmonic structures in the hotspots (regions 9 or 19 ). This is because particles in a fluid acquire an electrical double layer (layer of charge surrounding it that screens their surface charge). DC field causes a Faradaic reaction that results in the collapse of the electrical double layer as well as exerts a force on the particle drawing them closer to the electrode surface. As they are brought closer to the surface, short range interactions such as van der Waals can then kick in to hold them on the surface. The chip (system 100 OR 200 ) is then placed in an oven or otherwise heated to a few degrees above room temperature (e.g., less than ten degrees Celsius above room temperature), causing the polymer particles to expand and coat the plasmonic structures. If the polymer particles are loaded with biomolecules, the biomolecules will be released to selectively functionalize those specific regions. Furthermore, in another embodiment, selective tuning of resonance of the plasmonic systems can be achieved by capturing polymers of different optical properties, and heating them to coat the selected nanoantennas, thereby changing their dielectric environment and hence resonance spectrum. This can be used to achieve color printing with the plasmonic nanoantennas.
[0029] After being gathered or trapped using the above system, the particles may be sensed, imaged, or otherwise evaluated. In certain embodiments, the same light source 5 may be used to both create the hotspots in the focus regions and sense or image the particles. The light source 5 may also be optionally shaped or patterned to illuminate a selected subset of the microlenses 1 . In certain embodiments, the light source 5 may be polarized to focus light with a selected subset of the lenses, with the corresponding subset of lenses being polarization sensitive. For example, a first subset of the micro lenses may be configured to focus the selected polarization onto the plasmonic components array with a different functionalization for binding the concentrated target particles than a second subset of the micro lenses.
[0030] Steps of various methods described herein can be performed in any order except when otherwise specified, or when data from an earlier step is used in a later step. Exemplary method(s) described herein are not limited to being carried out by components particularly identified in discussions of those methods.
[0031] The invention is inclusive of combinations of the aspects described herein. References to “a particular aspect” (or “embodiment” or “version”) and the like refer to features that are present in at least one aspect of the invention. Separate references to “an aspect” (or “embodiment”) or “particular aspects” or the like do not necessarily refer to the same aspect or aspects; however, such aspects are not mutually exclusive, unless otherwise explicitly noted. The use of singular or plural in referring to “method” or “methods” and the like is not limiting. The word “or” is used in this disclosure in a non-exclusive sense, unless otherwise explicitly noted.
[0032] The invention has been described in detail with particular reference to certain preferred aspects thereof, but it will be understood that variations, combinations, and modifications can be effected within the spirit and scope of the invention.
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A particle sensing system which includes a plurality of micro-lenses which focus light from an unfocused or loosely focused light source onto a corresponding plurality of focus regions on a surface containing plasmonic structures. The absorption of light by the plasmonic structures in the focus regions results in heat dissipation in the plasmonic structures and consequently increases surface temperature in the focus regions. When an electrical field is applied to a sample fluid in contact with the surface, multiple electrothermal flows are induced in the fluid which rapidly transport suspended particles to the focus regions on the surface. The particles can then be captured and/or sensed.
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[0001] This application claims priority from provisional patent application Ser. No. 62/257,005 filed Nov. 18, 2015.
FIELD OF INVENTION
[0002] This invention relates to a novel cotton ginning rib for ginning seed cotton. In particular, this invention relates to the construction and features relating to how the novel rib is mounted in the gin stand, and incorporation of a rib spacer at the point where the rib meets at least one of the rib rails. Additionally, the rib design includes a feature allowing relief at the bottom of the rib to reduce the chances of accumulation of cotton fiber, thus reducing the chances for a fire created by the friction between the rotating gin saw and stationary cotton fiber inadvertently being held in place on the back surface of the lower section of the rib.
BACKGROUND
[0003] The process of picking cotton and removing seeds, trash and other foreign materials from the seed cotton is well known and understood by those familiar with the art. After seed cotton is harvested, it is then transported from the field to a cotton ginning facility. This facility has apparatus for receiving the seed cotton, drying and cleaning the seed cotton, removing the seeds from the cotton fiber or lint, cleaning the lint, and pressing the lint into bales for transport to warehousing, and later sold for commonly processing into yarn, thread, and fabric.
[0004] Central to the processes found in the type of cotton ginning facility relating to the present embodiment is the machine which separates the seed from the cotton fiber. This machine is referred to as a saw type ginning stand, or simply, a gin stand.
[0005] A typical prior art gin stand currently in use is shown in cross section in FIG. 1 . Referring to FIG. 1 , a gin stand 10 typically comprises an inlet chute 11 wherein seed cotton enters the machine in a single locked or separated state, and at a controlled rate. The seed cotton is urged by a picker roller 12 onto a gin saw cylinder 13 , comprised of a large number of spaced apart circular saw blades 14 having teeth along their periphery and rotating about a common axis 15 . The seed cotton is carried upward on the periphery of the saw blade through a seed discharge outlet 16 into the lower portion of the roll box 17 directly below an oscillator cylinder 18 . The multitude of saw blades 14 rotate between closely spaced stationary ginning ribs 19 which serve to strip a portion of the cotton fibers from each seed as the saw teeth and attached fibers pass between the closely spaced ribs.
[0006] The partially ginned seeds are larger than the gap between the ribs 19 , and become part of a seed roll rotating around the axis of the oscillator cylinder 18 . The fibers remaining on the partially ginned seed tends to keep the seed loosely attached to the seed roll, which is a large mass made up of seeds with varying amounts of fiber remaining. Each seed will rotate around the roll box 17 a multitude of times until it no longer has enough long fiber to keep it adhered to the seed roll, at which time it will fall out through the seed discharge outlet 16 and out of the bottom of the machine.
[0007] The cotton fiber passing between the ribs 19 will remain attached on the periphery of the saws until doffed off of the saw teeth by a counter-rotating brush cylinder 20 . The surface speed of the brush cylinder 20 is greater than the tip speed of the saw cylinder 13 , which allows the cotton to be lifted off the teeth of each saw blade 14 and passed out of the machine through the lint outlet 21 .
[0008] In cotton saw gin stands employing ribs 19 that are mounted at both the upper and lower extremities, the mounting surfaces typically lie in what are essentially parallel planes. The surface inside the gin stand where the upper end of the ribs 19 mount are commonly referred to as the upper rib rail 22 . Correspondingly, the surface where the lower end of the ribs 19 mount is known as the lower rib rail 23 .
[0009] Typically, ginning ribs are manufactured from a metal casting, usually iron or steel. The shape or profile of the rib 19 as viewed from one axial end of the rotating gin saw cylinder 13 shaft towards the other, and the distance between the parallel rib mounting planes 22 , 23 can vary from one model of gin stand to the next depending on a number of factors. Saws and ribs are high wear items and are therefore common replacement parts in existing saw gin stands.
SUMMARY OF THE INVENTION
[0010] An object of the present invention is to offer a novel saw ginning rib which can be manufactured by cutting the rib profile from a sheet of metal plate in a cost effective manner. Cutting ribs from plate in the axial profile direction has been considered cost prohibitive in the past.
[0011] It is another object of this invention to change the profile of the rib near at least one of the mounting surfaces so the rib mounting surfaces are no longer in essentially parallel planes, such that the ribs can be nested closely together when cutting from a sheet of raw plate material to reduce the amount of unused raw material, thus reducing the cost to manufacture significant quantities of the saw ginning ribs.
[0012] Since these saw ginning ribs are intended for use not only in new gin stands, but also in gin stands of existing design where the rib mounting surfaces lie in what are essentially parallel planes, it is necessary to also introduce a wedge-shaped spacer between the mating mounting surfaces of the gin rib and the gin stand rib rail. This wedge-shaped spacer can be manufactured to support a single or a multiple number of ribs. It is understood this spacer could also take forms other than a smooth wedge with one contiguous surface being in contact with the mounting surface of the ginning rib, and/or with one contiguous surface being in contact with the rib rail and still achieve the intended result.
[0013] A further object of this invention is to combine the function of a wedge-shaped spacer as described immediately above in conjunction with a plurality of grooves, each groove defined by two fins, with each groove having a tapered bottom to accept the mounting surface of one distal end of the ginning rib. The wedge-shaped spacer extends from one end of a rib rail to the other; however as a practical matter the spacer can be broken up into multiple pieces instead of one continuous piece, with each piece configured to hold one or more ribs. The rib correspondingly has a complimentary tapered bottom such that it sockets into the groove with the tapers serving to center each rib along the rail precisely spaced apart from one another as determined by the geometry of the spacer.
[0014] Another object of this invention is to reduce the tendency of undoffed cotton fiber from accumulating on the back side of a ginning rib. It is well understood by those familiar with the art of cotton ginning that cotton fiber can occasionally accumulate on the back side of a gin rib and create potential for a rib fire wherein the friction between the rotating saw blade and a stationary mass of cotton fiber generates enough heat to begin the combustion process. This object is accomplished by removing material from the back of the rib in the region where the periphery of the freshly doffed, rotating saw passes between the rib immediately prior to being exposed to fresh seed cotton urged onto the periphery of this rotating saw by the picker rollers such that corresponding tapers on either side of the rib allow any undoffed cotton fiber remaining on the saw teeth to easily pass between the ribs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Referring to the drawings which are appended hereto and which form a portion of this disclosure, it may be seen that:
[0016] FIG. 1 is a side cross section view of a modern gin stand containing conventional ginning ribs made of cast iron or cast steel.
[0017] FIG. 2 is a side cross section view similar to FIG. 1 , but with most features removed for the purposes of demonstration.
[0018] FIG. 3 is a side cross section similar to FIG. 2 , but fitted with ginning ribs of the present embodiment.
[0019] FIG. 4 is a view showing a set of ribs utilizing the traditional mounting arrangement nested together on a sheet of plate raw material.
[0020] FIG. 5 is a view showing a set of ribs of the present embodiment nested together on a sheet of plate raw material.
[0021] FIG. 6 is a side cross section showing the upper end of the rib and the wedge-shaped spacer of the present embodiment mounted to the upper rib rail.
[0022] FIG. 7 is an orthographic view of the wedge-shaped spacer.
[0023] FIG. 8 is an orthographic view showing the upper end of the rib and the wedge-shaped spacer of the present embodiment mounted to the upper rib rail.
[0024] FIG. 9 is a singular rib of the present embodiment with a
[0025] FIG. 10 is a sectional detail along section 10 - 10 of FIG. 9 showing the tapered relief of the tuft region on the back of the rib near the lower end of the rib.
DETAILED DESCRIPTION
[0026] One or more of the above objects can be achieved, at least in part, by providing ginning ribs which utilize less material in creation. As shown in FIG. 2 , a traditional cast iron or cast steel rib 19 is mounted to the upper rib rail 22 and lower rib rail 23 , in close proximity to the circular gin saw 14 . It should be noted that the mounting surfaces of the rib 19 and rib rails 22 , 23 are essentially in parallel planes.
[0027] As best seen in FIG. 3 , the rib 29 of the current embodiment is mounted to the upper rib rail 22 and lower rib rail 23 , in close proximity to the circular gin saw 14 . It should be noted that the upper and lower mounting surfaces of the rib 29 are not essentially in parallel planes.
[0028] As illustrated in FIG. 4 , hypothetically a nest, or grouping of ribs having the same configuration as prior art cast ribs with mounting surfaces in essentially parallel planes could be arranged on a sheet of raw plate material in a manner to best utilize the raw material in cutting the ribs from the material rather than making them from cast iron. In this hypothetical , the ribs are oriented such that the width of the rib is defined as the raw material thickness, albeit prior to subsequent machining processes; the outline or profile of the rib as seen in this view will be cut in a plane parallel to the axis of rotation of the saw cylinder in the finished gin stand. The mounting surfaces on the rib 24 , 25 can be readily identified by the close proximity to the mounting holes 26 , 27 where a fastener is used to attach the rib to the rib rail. It is important to note that rib 28 is of a hypothetical design not currently commercially available and is considered to be cost prohibitive, and is essentially employed herein as a construct to demonstrate by contrast the features of the current embodiment. Specifically note the spacing A and B between the ends of adjacent ribs wherein waste material would be left by this hypothetical design.
[0029] As illustrated in FIG. 5 , a nest, or grouping of ribs 29 of the present embodiment with mounting surfaces 24 ′, 25 ′ oriented essentially in-line with the immediately proximate segment of rib can be arranged on a sheet of raw plate material in a manner to best utilize the raw material when cutting ribs therefrom. This requires the mounting surfaces 24 ′, 25 ′ to not be oriented essentially parallel. It will be noted this arrangement allows for more efficient usage of the raw material than the rib shown in FIGS. 2 and 4 , by eliminating the waste shown at A and B of FIG. 4 , thus allowing the possibility for more ribs to be cut from a similar sized sheet of raw material, and reducing the amount of raw material wasted. Furthermore, the ribs are oriented such that the width of the rib is defined as the raw material thickness, albeit prior to subsequent machining processes; the outline or profile of the rib as seen in this view will be cut in a plane parallel to the axis of rotation of the saw cylinder once assembled in the finished gin stand. The mounting surfaces on the rib 24 ′, 25 ′ can be readily identified by the close proximity to the mounting holes 26 ′, 27 ′ where a fastener is used to attach the rib to the rib rail.
[0030] Since the upper proximal end of rib 29 and its corresponding mounting surface is not in a parallel plane with the corresponding mounting surface of the upper rib rail 22 , there is introduced a wedge-shaped spacer or filler bar 30 to allow the mounting of the rib to the rib rail even though they do not share a common plane along the corresponding mounting surfaces.
[0031] FIG. 6 shows the rib 29 of the current embodiment at the upper proximal end where it meets the upper rib rail 22 and the filler bar 30 . This illustration is essentially the same as FIG. 3 , but is a magnified view of one area of interest, and serves to show greater detail of this connection point.
[0032] As can be seen in FIG. 7 , one embodiment of the filler bar 30 has a series of grooves corresponding to the width of the upper end of the rib 29 of the current embodiment. It is to be understood that the filler bar can include any number of grooves and may be unitary across the width of the rib rail or be composed of a number of like units affixed end to end across the width of the rib rail.
[0033] As best demonstrated in FIG. 8 , the upper end of the rib 29 has tapered or beveled surfaces 29 ′ that correspond to the beveled grooves 30 ′ in the filler bar 30 . It can also be seen that both the width and taper of the mounting surface of the upper end of the rib 29 are complimentary and can be manufactured in such a way that once installed, the spacing and angular positioning of the ribs 29 can be precisely and uniformly set.
[0034] Referring to FIGS. 9 and 10 note that a novel bevel is created when material is removed from the back of the rib 29 in a tuft region where the periphery of the freshly doffed, rotating saw 14 passes between the ribs immediately prior to being exposed to fresh seed cotton thrown onto the periphery of this rotating saw by the picker roller. When multiple ribs are aligned with corresponding tapers on either side of the ribs allows any undoffed cotton fiber remaining on the saw teeth to easily pass between the ribs. As shown in FIG. 9 , the rib 29 of the present embodiment includes a novel bevel 31 in the tuft region facing the oncoming saw and created by the bi-lateral removal of material from the parent raw material.
[0035] While in the foregoing specification this invention has been described in relation to certain embodiments thereof, and many details have been put forth for the purpose of illustration, it will be apparent to those skilled in the art that the invention is susceptible to additional embodiments and that certain of the details described herein can be varied considerably without departing from the basic principles of the invention.
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A ginning rib for use in a saw type cotton gin stand constructed from a plate or sheet of raw material, with the material thickness defining the width of the rib, and the shape or profile of the rib defined by the path of the cutting means of the plate or sheet. Furthermore, the shape of the rib being such that it can be economically produced with current cutting technology while concurrently of a unique design to reduce raw material waste, and to include features improving functional reliability and serviceability.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application Ser. No. 13/962,757, filed Aug. 8, 2013, entitled “VIRAL FUSION PROTEIN TREATMENT FOR CCR8 MEDIATED DISEASES”.
SEQUENCE LISTING
[0002] The instant application contains a Sequence Listing which has been submitted in ASCII format via EFS-Web and is hereby incorporated by reference in its entirety. Said ASCII copy, created on Jul. 31, 2013, is named 12744-700 — 200_SL_txt and is 7,483 bytes in size.
INCORPORATION BY REFERENCE
[0003] All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.
FIELD
[0004] The present invention relates to the treatment of disorders of skin and of other organs, more particularly atopic dermatitis, mediated by chemokine receptor CCR8, using compositions which include a protein derived from Molluscum contagiosum Virus (MCV).
BACKGROUND
[0005] Atopic dermatitis (AD) is a genetically determined, reaginically (IgE) associated, chronic disease of the skin in which the skin is dry, easily irritated, allergen predisposed, typically scaly, often thickened, commonly red, sometimes exudative, frequently infected and above all itchy. In the United States prevalence rates in childhood range from 8.7 to 18.1% with higher rates in metropolitan areas and among the more affluent. (J Invest Dermatol 131:67-73, 2011). AD may persist into or reappear in adulthood, but may also arise in adult life. (J Am Acad Dermatol 52:579-82, 2005). In industrialized countries, the prevalence rates in childhood range from 15 to 30% and in adults from 2 to 10% of the general population. (NEJM 358:1483-94, 2008). AD adversely affects the quality of life of the patients and their families and imposes a significant financial burden measured in billions of dollars (J Manag Care Pharm 13:349-59, 2007).
[0006] Atopic dermatitis is characterized both by a defective skin barrier, the stratum corneum, and by a defective immune response, characterized by Th2 dominance. In the former case, disease pathogenesis follows an outside-to-inside pathway and in the latter case, disease pathogenesis follows an inside-to-outside pathway. (J Invest Dermatol 128:1067-1070, 2008).
[0007] Pursuant to outside-to-inside pathogenesis, there are 2 main attributes of the defective skin barrier. One of these attributes results from a deficiency in ceramides, the main lipid in the stratum corneum. Ceramide deficiency characterizes patients with AD, noting that ceramides consist of a union between long chain fatty acids (FA) and sphingosine (S) bases. There is a significant reduction in esterified omega-OH-FA and sphingosine base (EOS), in esterified omega-OH-FA and 6-OH-sphingosine base (EOH), in esterified omega-OH-FA and phytosphingosine base (EOP), in non-OH-FA and 6-OH-sphingosine base (NH), and in non-OH-FA and phytosphingosine base (NP). (J Invest Dermatol 130:2511-14, 2010). The esterified omega-OH-ceramides exist in free and in bound forms—the latter being bound to proteins of the keratinocytic cornified envelope, mostly involucrin. In non-lesional and yet more in lesional skin of patients with AD, there is a marked reduction of these esterified ceramides bound to the cornified envelope. Similarly there is a marked reduction of free extractable very long chain FA, i.e. >24 carbon atoms, both in non-lesional and more severely in lesional skin of patients with AD. These defects contribute to the barrier impairment seen in AD. (J Invest Dermatol 119:166-73, 2002). These changes in ceramide composition are associated with a change in the lamellar lipid organization in AD patients. (J Invest Dermatol 131:2136-38, 2011).
[0008] The other main attribute results from genetically induced deficiency in filaggrin, a histadine rich protein whose diminution is found in about ⅓ of patients with AD and in whom clinical severity correlates with transepidermal water loss (TEWL) and poor stratum corneum hydration, whereas similar correlation does not pertain in patients lacking filaggrin deficiency. (J Invest Dermatol 129:682-89, 2008). Yet barrier abnormalities remain in patients with AD lacking filaggrin deficiency, further noting that filaggrin deficiency alone is not sufficient to generate AD as in patients with ichthyosis vulgaris. Nonetheless AD patients with filaggrin mutations have reduced hydroscopic amino acids as well as reduced tight junctions and reduced corneodesmosin, yielding defective intercorneocyte adhesion. These patients manifest persistent disease, a higher incidence of eczema herpeticum, irritant contact dermatitis, allergic contact dermatitis, peanut allergy and asthma. (NEJM 365:1315-27, 2011). Further, filaggrin breakdown products include polycarboxylic acids—the lack of which increases stratum corneum pH, which in turn activates serine proteases. These proteases appear to induce corneocytes to release IL-1a and IL-1β from their pro-forms, initiating inflammatory pathways. These proteases may also mediate Th2 inflammation, even in the absence of allergen priming. (J Exp Med 206:1135-47, 2009).
[0009] Pursuant to inside-to-outside pathogenesis, Th2 cytokines may impair the skin barrier. Th2 cytokines include IL-4, IL-5, IL-6, IL-10 and IL-13 (J Invest Dermatol Symp Proc 9:23-8, 2004). Among these cytokines, it has been shown that IL-4 not only inhibits ceramide synthesis in cultured keratinocytes (J Invest Dermatol 124:786-92, 2005) but also inhibits epidermal differentiation complex genes, resulting in significantly lower levels of filaggrin, loricrin and involucrin (J Invest Dermatol 130:S116, 2010). Indeed both Th2 cytokines IL-4 and IL-13 inhibit both filaggrin and human β-defensin 3 expression. (J Invest Dermatol 128: 2248-58, 2008). IL-22 is found in AD skin. It, too, down regulates filaggrin expression in keratinocytes. IL-10 down regulates anti-microbial peptide expression in AD (J Invest Dermato 125:738-45, 2005). IL-31, highly expressed in skin samples of AD patients and associated with the itching of AD, inhibits the expression of terminal differentiation markers including filaggrin (J All Clin Immunol 129:426-33, 2012). Further IL-31 treated skin models resulted in increased uptake of allergens of timothy grass and cat dander, demonstrating increased transepidermal penetration of environmental allergens (J Invest Dermatol 132: S78, 2012).
[0010] Dendrocytes are increased in number in AD skin and produce IL-25 (IL-17E). IL-25 levels are elevated in the skin of AD patients and it induces and prolongs Th2 immune responses. Specifically, IL-25 induces production of IL-4, IL-5, IL-13, IgE and eosinophilia in a murine model of asthma. In addition to this, IL-25 decreases synthesis of filaggrin in cultured keratinocytes (J Invest Dermatol 131:150-7, 2011). Kallikrein, including kallikrein 7, are serine proteases, elevated in the epidermis of AD patients. Overexpression of human kallikrein 7 in murine epidermis results in a chronic itchy dermatitis. Cultured normal human epidermal keratinocytes treated with IL-4 or IL-13 increased kallikrein levels. Kallikreins 1, 8, 11, 12 and 13 were similarly induced (J Invest Dermatol 130:S47, 2010). Kallikreins elevate tissue pH which impairs glucocerebrosidase and sphingomyelinase—both of which require acidic pH, resulting in impaired ceramide production and impairment of the skin barrier.
[0011] It has been shown that Th2 cytokines and Th22 cytokines remain dominant in acute and chronic phases of AD. A claim that acute AD is followed by chronic AD is somewhat of a mischaracterization because AD is almost always a chronic dermatitis in which the patient clinically experiences (acute) flares of AD. Irrespective of such characterization, Th2 cytokines, including IL-4 and IL-10, as well as Th22 cytokines, IL-22 and IL-31, are up regulated in “acute” AD and are increased even more in “chronic” AD such that Th2 and Th22 cytokines are dominant throughout the disease course (J Invest Dermatol 132:S13, 2012).
[0012] The frequent chronic infections that occur on and in the skin of AD patients appear to result both from the defective skin barrier of AD and from an impaired immune response, e.g. upon testing with trichophyton antigen, patients with AD show immediate rather than the normal delayed immune response. The most common of the microbes infecting AD skin is Staphylococcus aureus (Staph). In AD skin, Staph induces and exacerbates itching, increases inflammation and provokes oozing and eczematization. Of patients whose skin oozes, 100% will culture out Staph. Of those who do not ooze, the majority will still culture out Staph, although less massively. Staph binds readily to Th2 inflamed skin as compared with Th1 inflamed skin, perhaps accounting for the high colonization rate of AD skin (J Invest Dermatol 116:658-63, 2001).
[0013] Staph contributes to AD disease expression. Lipoteichoic acid is a constituent of the cell wall of Staph. It is a potent agonist of platelet-activating factor receptor (PAF-R). Lipoteichoic acid and PAF-R suppress Th1 type reactions but up-regulate production of IL-10, a Th2 cytokine (J Am Acad Dermatol AB12, March 2005), contributing to the Th2 dominant inflammation of AD. Further IL-10 is elevated in both extrinsic and intrinsic forms of AD. IL-10 inhibits the expression of antimicrobial peptides, enabling Staph colonization (J Invest Dermatol 125:738-745, 2005). Staph derived ceramidase may aggravate the skin barrier defect of AD. Staph enterotoxins inhibit the suppressive activity of regulatory T cells and correlate with AD severity. Staph exotoxins up-regulate Th22 cell production of the highly pruritogenic IL-31. About 50% of patients with AD produce IgE directed against Staph toxins and IgE is a chief mediator of Th2 inflammation.
[0014] Viruses, too, more readily grow in AD skin than in normal skin. Viruses commonly colonizing AD skin include herpes simplex, verruca vulgaris and molluscum contagiosum.
[0015] There is no known cure for AD. The many treatment approaches attest the inadequacy and limitations of each. In briefest outline, these treatments include avoidance of soap, irritants and allergens, hydration of the skin, dietary restrictions, tars, antihistamines, hyposensitization, corticosteroids, antibacterials, antifungals, antivirals, ultraviolet light, leukotriene blockers, inhibitors of mast cell content release, evening primrose oil, Chinese herbal teas, pentoxifylline, pimecrolimus, tacrolimus, azathioprine, cyclosporin A, cyclophosphamide, interferon γ, thymopentin and phosphodiesterase inhibitors. The corticosteroids are most commonly used in clinical practice, but suffer from incomplete responses, tachyphylaxis, induction of atrophy and the potential of suppression of the pituitary-adrenal axis if used widely enough, long enough and potently enough.
SUMMARY OF THE DISCLOSURE
[0016] The present disclosure relates to compositions, methods and kits for treating atopic dermatitis, other atopic diseases, including asthma, allergic rhinitis, hives, other Th2 mediated diseases and diseases mediated by the CC chemokine receptor, CCR8. Compositions, methods, and kits are provided for treating CCR8 mediated diseases with applicability to atopic dermatitis and potential applicability to asthma, prurigo nodularis, nummular dermatitis, neurodermatitis, and lichen simplex chronicus as well as some lymphomas, multiple sclerosis, acquired immunodeficiency disease, peritoneal adhesions, Kaposi's sarcoma and atherogenesis—the expression of all of which, at least in part, is mediated by cells expressing the chemokine receptor CCR8. The compositions according to the present disclosure include proteins from Molluscum Contagiosum Virus (MCV), short or long peptide sequences fused to MCV proteins, or fragments, variants, analogs, and derivatives thereof which exhibit AD and CCR8 inhibiting activity plus the capacity to penetrate intact human skin as well as exhibiting the inhibition of chemotaxis and/or function of cells expressing CCR8, including Th2 cells, monocytes, macrophages, dendrocytes, Langerhans cells, natural killer cells, endothelial cells, and smooth muscle cells (Blood 103:1296-1304, 2004). Examples of MCV proteins which exhibit AD inhibiting activity plus the capacity to penetrate intact human skin as well as exhibiting the inhibition of chemotaxis and/or function of cells expressing CCR8, include MC148p1 (Molluscum Contagiosum 148 protein—being the product of type 1 MCV gene/open reading frame 148, reading right), MC148p2, MC148p3, MC148fp (Molluscum Contagiosum 148 protein fused with one or more than one short peptide sequence and/or with one or more than one long peptide sequence, variants, analogs and derivatives thereof which exhibit AD inhibiting activity, human skin penetrating capacity and/or exhibiting the inhibition of chemotaxis and/or function of cells expressing CCR8 and other MC148p and MC148fp types of proteins which possess AD inhibiting and/or human skin penetrating capacity as well as exhibiting inhibition of cells expressing CCR8. Such a short or long peptide sequence fused with Molluscum Contagiosum 148 protein may be a TAT sequence (such as described herein). Such a TAT sequence may be fused to the N-terminus of the Molluscum Contagiosum 148 protein, may be fused to the C-terminus of the Molluscum Contagiosum 148 protein, or may be placed in the middle of the Molluscum Contagiosum 148 protein. In some embodiments, a TAT sequence may be separated from the Molluscum Contagiosum 148 protein on the N-terminus or on the C-terminus by another peptide, such as a spacer or another domain-containing peptide. Such a short or long peptide sequence fused with Molluscum Contagiosum 148 protein may be a polyHis peptide. A polyHis peptide may include, for example, from 3-20 histidine residues (SEQ ID NO: 8), from 4-12 histidine residues (SEQ ID NO: 9), from 5-8 histidine residues (SEQ ID NO: 10), or may include 6 histidine residues (“6xHis”) (SEQ ID NO: 11). In some embodiments, such a polyHis sequence may be separated from the Molluscum Contagiosum 148 protein on the N-terminus or on the C-terminus by another peptide, such as a spacer or another domain-containing peptide. In some embodiments, such a polyHis sequence may be in the middle of a Molluscum Contagiosum 148 protein. In some embodiments, an MC 148 fusion protein (MC148fp) includes a Molluscum Contagiosum 148 protein with a TAT sequence fused to its C-terminal end and a 6xHis (SEQ ID NO: 11) sequence fused to the TAT sequence (MC148p-C-TAT-6xHis (“6xHis” disclosed as SEQ ID NO: 11)). In some embodiments, an MC148 fusion protein (MC148fp) includes a Molluscum Contagiosum 148 protein with a TAT sequence at its C-terminal end and a 6xHis (SEQ ID NO: 11) sequence located C-terminal to the TAT sequence with a spacer or another peptide (e.g. a domain peptide) separating the MC148 from the TAT and/or from the 6xHis (SEQ ID NO: 11).
[0017] The fragments, variants, analogs, derivatives and fusions may be less than 100% homologous to MC148p1, MC148p2, MC148p3 as well as MC148fp1, MC148fp2, MC148fp3 so long as they are sufficiently homologous such that AD inhibiting activity and/or human skin penetrating capacity and/or exhibiting inhibition of chemotaxis or function of cells expressing CCR8 are preserved. Collectively, the above MCV proteins, fusions proteins, fragments, variants, analogs and derivatives are referred to herein as MC 148 proteins (MC 148p) and MC 148 fusion proteins (MC148fp).
[0018] In one embodiment, the composition is suitable for topical application to a portion of patient's skin which exhibits AD signs and/or symptoms. In another embodiment, the composition is adapted for delivery by other routes including by injection intravenously, intramuscularly, subcutaneously or intradermally or by electroporation or iontophoresis. The composition may be delivered systemically to treat Th2 mediated diseases or to treat CCR8 mediated diseases or it may be delivered remotely or locally at or near a portion of patient's skin which exhibits AD signs and/or symptoms or related skin or non-skin inflammatory diseases.
[0019] The disclosure also relates to a kit which includes a composition according to the present disclosure. The kit may optionally include multiple separately packaged portions of the composition, where each portion is in an amount suitable for a single administration or for multiple administrations, e.g. administration from an intravenous line, a syringe, a bottle, a tube or a jar. The kit may also optionally include instructions regarding the administration of the composition to a patient having AD, other atopic diseases, other inflammatory disorders, Th2 mediated diseases or CCR8 mediated diseases. In one of the many variations, the instructions may teach how to administer the composition systemically or locally to the patient.
[0020] One aspect of the invention provides a method for treating a patient having at least one of atopic dermatitis, an atopic dermatitis-related atopic disease, an allergic disease, a Th2 mediated disorder and a CCR8 mediated disorder, including the steps of administering to a patient having at least one of atopic dermatitis, an atopic dermatitis-related atopic disease, an allergic disease, a Th2 mediated disorder or a CCR8 mediated disorder, a therapeutically effective amount of a composition comprising a Molluscum contagiosum viral fusion protein MC148p-TAT-poly-His (MC148fp) which possesses at least one of atopic dermatitis inhibitory activity, an atopic dermatitis-related atopic disease inhibitory activity, an allergic disease inhibitory activity, a Th2 mediated disorder inhibitory activity or a CCR8 mediated disorder inhibitory activity. In some embodiments, administering to a patient includes administering an MC148fp selected from the group consisting of Molluscum contagiosum viral fusion protein 148fp1 (MC148fp1), Molluscum contagiosum viral fusion protein 148fp2 (MC148fp2), Molluscum contagiosum viral fusion protein 3 (MC148fp3) and a fragment, a variant, an analog and a derivative of these compositions, fused with C-terminal TAT and poly-His. In some such embodiments, the method includes administering an MC148fp selected from the group consisting of Molluscum contagiosum viral fusion protein 148fp1 (MC148fp1), Molluscum contagiosum viral fusion protein 148fp2 (MC148fp2), Molluscum contagiosum viral fusion protein 3 (MC148fp3) and a fragment, a variant, an analog and a derivative of these compositions, fused at its C-terminus with TAT wherein the TAT is fused with 6xHis (SEQ ID NO: 11).
[0021] In some embodiments, the method of administering the composition includes topically applying the composition. In some embodiments, the method of administering the composition includes injecting the composition into the patient. In some embodiments, the method of administering the composition includes performing iontophoresis. In some embodiments, the method of administering the composition includes electroporating the composition. In some embodiments, the method of administering the composition includes administering a liposomal carrier to the patient. In some embodiments, the method of administering the composition includes administering a skin penetration enhancement carrier. In some embodiments, the method of administering the composition includes administering nanoparticles, such as, e.g. alginate-chitosan nanoparticles. In some embodiments, the method of administering the composition includes delivering the composition locally to an area of patient skin affected with at least one of atopic dermatitis, an atopic dermatitis-related atopic diseases, an allergic disease, a Th2 mediated disorder and/or a CCR8 mediated disorder. In some embodiments, the method of administering the composition includes delivering the composition to an area of patient skin lacking atopic dermatitis, an atopic dermatitis-related atopic diseases, an allergic disease, a Th2 mediated disorder and a CCR8 mediated disorder. In some embodiments, the method of delivering the composition further includes penetration of the composition through a stratum corneum of the patient.
[0022] Another aspect of the invention provides a kit for treating at least one of atopic dermatitis, an atopic dermatitis-related atopic diseases, an allergic disease, a Th2 mediated disorder or a CCR8 mediated disorder, including: multiple separately packaged portions of a composition adapted for such treatment comprising a therapeutically effective amount of a composition comprising a Molluscum contagiosum viral fusion protein MC 148p-TAT-polyHis (MC148fp) which possesses at least one of atopic dermatitis inhibitory activity, an atopic dermatitis-related atopic disease inhibitory activity, an allergic disease inhibitory activity, a Th2 mediated disorder inhibitory activity and a CCR8 mediated disorder inhibitory activity.
[0023] In some embodiments, the MC148fp is selected from the group consisting of Molluscum contagiosum viral fusion protein 148fp1 (MC148fp1), Molluscum contagiosum viral fusion protein 148fp2 (MC148fp2), Molluscum contagiosum viral fusion protein 3 (MC148fp3) and a fragment, a variant, an analog and a derivative of these compositions, fused with C-terminal TAT and polyHis in either order and with or without spacer peptides. In some embodiments, the MC148fp is selected from the group consisting of Molluscum contagiosum viral fusion protein 148fp1 (MC148fp1), Molluscum contagiosum viral fusion protein 148fp2 (MC148fp2), Molluscum contagiosum viral fusion protein 3 (MC148fp3) and a fragment, a variant, an analog and a derivative of these compositions, fused with C-terminal TAT and 6xHis (SEQ ID NO: 11) wherein the 6XHis (SEQ ID NO: 11) is C-terminal to the TAT.
[0024] In some embodiments, the kit further includes instructions teaching administration of the composition to a patient having at least one of the above-mentioned ailments. In some such embodiments, the instructions teach local delivery of the composition to a patient skin area having, adjacent to, or distant from at least one of the above-mentioned ailments. In some embodiments, the instructions teach topical application of the composition. In some embodiments, the instructions teach injection of the composition. In some embodiments, the instructions teach administering the composition through iontophoresis. In some embodiments, the instructions teach administering the composition through electroporation. In some embodiments, the instructions teach administering a composition that includes a liposomal carrier. In some embodiments, the instructions teach administering a composition that includes a skin penetration enhancer. In some embodiments, the instructions teach administering a composition that includes nanoparticles, such as e.g., alginate-chitosan nanoparticles.
[0025] Another aspect of the invention provides a composition including a Molluscum contagiosum viral fusion protein (MC148p-TAT-polyHis) which possesses atopic dermatitis inhibiting activity.
[0026] In some embodiments, the composition includes Molluscum contagiosum viral fusion protein (MC148p-TAT-6XHis (“6XHis” disclosed as SEQ ID NO: 11)) which possesses atopic dermatitis inhibiting activity. In some embodiments, the composition further comprises PBS or other vehicles such as creams, lotions or gels, including hydrogels or occlusion techniques.
[0027] In some embodiments, the composition includes a pharmaceutically acceptable carrier. In some embodiments, the composition includes a skin penetration enhancer. In some embodiments, the composition includes dimethylsulfoxide. In some embodiments, the composition includes a liposomal carrier with or without a hydrogel. In some embodiments, the composition includes nanoparticles, such as, e.g., alginate-chitosan nanoparticles.
[0028] In some embodiments, the MC148p-TAT-polyHis is selected from the group consisting of: MC148fp1, MC148fp2, and MC148fp3.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] The novel features of the invention are set forth with particularity in the claims that follow. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:
[0030] FIG. 1A illustrates the DNA sequence (SEQ. ID. No. 1) of MCV type 1, ORF 148 R.
[0031] FIG. 1B illustrates the amino acid sequence (SEQ. ID. No. 2) of the protein produced from the DNA sequence of MCV type 1, ORF 148 R, illustrated in FIG. 1A .
[0032] FIG. 2A illustrates the DNA sequence (SEQ. ID. No. 3) of MCV type 2, ORF 148 R.
[0033] FIG. 2B illustrates the amino acid sequence (SEQ. ID. No. 4) of the protein produced from the DNA sequence of MCV type 2, ORF 148 R, illustrated in FIG. 2A .
[0034] FIG. 3 illustrates the DNA sequence (SEQ. ID. No. 5) of MCV ORF 148 R from the index case—the DNA of which is identical to that of MCV type 1, ORF 148 R, shown for nucleotides 21-312.
[0035] FIG. 4A illustrates the DNA sequence (SEQ. ID. No. 6) of MCV ORF 148 R to which is fused the 33 nucleotides used to produce the TAT sequence and the 18 nucleotides used to produce the sequence of 6 histidines (SEQ ID NO: 11) at the carboxyl terminal of MCV ORF 148 R.
[0036] FIG. 4B illustrates the amino acid sequence (SEQ. ID. No. 7) of the protein produced from the fusion DNA sequence illustrated in FIG. 4A . FIG. 4B discloses “6xHis” as SEQ ID NO: 11.
[0037] FIG. 5A illustrates the clinically demonstrable inhibitory effect of MCV upon a field of AD at a focal distance of 15 centimeters.
[0038] FIG. 5B illustrates the clinically demonstrable inhibitory effect of MCV upon a field of AD at a focal distance of 5 centimeters.
[0039] FIG. 6A illustrates the microscopically demonstrable inhibitory effect of MCV upon a field of AD.
[0040] FIG. 6B illustrates the appearance of AD in the same patient shown in FIG. 5A at the same time at a site of AD remote from MCV.
[0041] FIG. 7A illustrates by means of immunohistochemistry, using 6xHis (SEQ ID NO: 11) antibody, the penetration of MC 148 fusion protein through the stratum corneum and its concentration along the basal cell layer of the epidermis.
[0042] FIG. 7B illustrates by means of immunohistochemistry, using Collagen 1A antibody and omitting 6xHis (SEQ ID NO: 11) antibody, both positive and negative controls.
[0043] FIG. 8A illustrates 1-309 induced chemotaxis inhibited by recombinant MC 148 protein with an IC50 at about 2 nM whereas synthetic MC 148 protein fails to obtain an IC50 even at 15,000 nM.
[0044] FIG. 8B illustrates 1-309 induced chemotaxis inhibited by recombinant MC 148 fusion protein with an IC50 at about 200 nM. FIG. 8B discloses “6His” as SEQ ID NO: 11.
DETAILED DESCRIPTION
[0045] Atopic dermatitis remains a vexing problem for the multitude of individuals suffering with it. Better methods and compositions for treating it are warranted. The compositions of the present disclosure include MC 148 proteins and fusion proteins which exhibit AD inhibiting activity and/or human skin penetration capacity and/or inhibition of chemotaxis and/or function of cells expressing CCR8. As noted above, these proteins may be MCV proteins or MCV fusion proteins such as MC148p1, MC148p2, MC148p3, MC148fp1, MC148fp2, MC148fp3 as well as other fusions, fragments, variants, analogs, and derivatives of the MCV proteins, including those described in U.S. Pat. No. 6,838,429 to David A. Paslin, which exhibit AD inhibiting activity and/or human skin penetration capacity and/or inhibition of chemotaxis and/or function of cells expressing CCR8. The fusions, fragments, variants, analogs and derivatives may be less than 100% homologous to a MCV protein so long as they are sufficiently homologous such that AD inhibiting activity and/or human skin penetration activity and/or inhibition of chemotaxis and/or inhibition of function of cells expressing CCR8 are preserved.
[0046] Molluscum Contagiosum Virus (MCV) is a large 190 kDa DNA virus of the Pox family. MCV causes small, harmless lesions in the skin of infected persons. These small papules (bumps) resemble pimples that typically appear domed, shiny and often show a small central invagination (pit). MCV can be spread from person to person by direct skin contact and by fomites. It is harmless, non-invasive and has no cancerous potential. MC148p1 is natively produced by MCV type 1. MC148p2 is natively produced by MCV type 2.
[0047] The Applicant has observed in his clinical practice of medicine the inhibitory effect of MCV upon AD. The inhibitory effect endured at least 6 years, i.e. for the duration of the MCV infection, without any clinical side effect and without tachyphylaxis. By viewing macro-lens photographs at focal distances of 15 cm ( FIG. 5A ) and of 5 cm ( FIG. 5B ) one sees a field of AD manifest as mildly scaly, somewhat lichenified reddish brown skin. Clear zones of clinically normal skin surround each papule of MCV. The zone of inhibition around each MCV papule may be viewed as analogous to the zone of inhibition around a penicillin disk on an agar plate streaked with Streptococci. The therapeutic implications are also analogous.
[0048] FIG. 6A shows a photomicrograph of a biopsy taken at the edge of and immediately adjacent to a papule of MCV. The edge of the papule is seen at the lower left of the panel. The top of the panel shows the base of the epidermis. A paucity of mononuclear cells is accompanied by a paucity of small blood vessels in the dermis adjacent to the MCV papule. The lack of inflammation in the dermis adjacent to the MCV papule resembles the appearance of the dermis in normal, i.e. non-AD skin. By contrast, FIG. 6B shows a photomicrograph of a biopsy taken concurrently from a similar area of AD on the same patient, but remote from any MCV papule. The moderately dense, predominantly lymphohistiocytic/dendrocytic infiltrate admixed with eosinophils is seen not only around the blood vessels of the superficial plexus, but also around vessels of the papillae and those of the upper reticular dermis. The inflammatory cells extend into the interstitium.
[0049] The Applicant interprets the above observations to show that MCV produces a protein that inhibits the signs and symptoms of AD. This protein is believed to be MC148p1. Published work indicates that MC 148p2 and other MC 148 proteins share the same or similar anti-inflammatory properties. (Krathwohl M D et al. in Proc Nat'l Acad Sci 94:9875-98801997; Bugert J J et al. in Virology 242:51-59, 1998; Damon I et al. in Proc Nat'l Aca Sci 95-6403-6407, 1998.)
[0050] MCV type 1 is the major type of MCV found in nature and has of 190,289 base pairs. This comprises the entire genome, excepting covalently closed terminal hairpin loops. This genome was deposited in Gen Bank (accession number U60315) as described by Senkevich T G “Genome Sequence of a Human Tumorigenic Poxvirus: Prediction of Specific Host Response-Evasion Genes” in Science 273:813-816, 1996. MCV type 1 includes a DNA sequence of 312 base pairs, identified as ORF 148 R, that encode a protein of 104 amino acids in length referred to herein as MC148p1. Synthesis, characterization and effects of MC are discussed in Damon I et al. “Broad Spectrum Chemokine Antagonistic Activity of a Human Poxvirus Chemokine Homolog” Proc Nat'l Acad Sci USA 95:6403-6407, 1998 and in Krathwohl M D et al. “Functional Characterization of the C—C Chemokine-like Molecules Encoded by Molluscum Contagiosum Virus Types 1 and 2” Proc Natl Acad Sci USA 94:9875-9880, 1997.
[0051] The DNA sequence of MCV 148 type 1 (SEQ ID No. 1) is illustrated in FIG. 1A and the amino acid sequence of MC148p1 is provided in FIG. 1B . MC148p2 (also denoted MC148R 2 Protein), produced by MCV type 2, is a variant of MC148p1. MC148p2 is also 104 amino acids in length. The DNA sequence for MCV type 2 (SEQ ID No. 3) is illustrated in FIG. 2A and the amino acid sequence of MC148p2 (SEQ ID No. 4) is illustrated in FIG. 2B . The DNA sequence for MC148R2 has been deposited in Gen Bank (Accession number U96749) by Krathwohl et al., as referenced above.
[0052] MC148R2 has 89% homology to MC148R1. Amino acid sequences of MC148R2 protein (MC148p2) showed 87% homology with those of MC for complete sequences and 86% homology when the putative leader sequence was removed. From the amino terminus, the leader sequences of MC148p1 and MC148p2 consist of 24 amino acids of which 20 amino acids share identical positions. The chemokine activation domain, found between positions 24 and 25 of MC148p1 and MC148p2 is absent in both. The 5 amino acids of positions 25-29, comprising the hypothetical receptor binding site, are identical except at position 26 where MC 148p2 bears a serine substitution for the alanine residue found in most isolates of MC148p1. This substitution at position 26 does not appear to affect the inhibitory activity of either type of MC148p. The leucine at position 47 from the amino terminus, correlated with the ability of MC148p to inhibit neutrophil chemotaxis, is conserved in MC148p1 and MC148p2.
[0053] Further, the amino acid sequences of MC and MC148p2 share significant homology with CC (β) chemokines such as macrophage inflammatory protein-1α (MIP-1α) and MIP-1β (Krathwohl et. see above) and CC (β) chemokines including RANTES, macrophage chemotactic proteins-1 and -3 (MCP-1 and MCP-3) (Damon et al., see above). The amino acid sequences of MC and of MC148p2 also share significant homology with CXC (α) chemokines SDF-1 for the attraction of monocytes and lymphocytes and IL-8 for the attraction of neutrophils. MC148p1 and MC148p2 share the identical positions of the 4 canonical cysteine residues with the above mentioned CC chemokines at positions 30, 31, 59 and 75 of the respective amino acid chains. Taken together, these structural homologies may best account for the capacity of MC148p to inhibit the chemotaxis of human peripheral blood mononuclear cells (Krathwohl et al.) and of monocytes, lymphocytes and neutrophils (Damn et al.). The inhibition results from the direct binding of MC148p to chemokine receptor(s). It is emphasized, however, that Luttichau et al. in contrast with Damon et al. did not find “promiscuous” inhibition of multiple receptors by MC148p but rather selective inhibition of CCR8 activation by 1-309 induced calcium mobilization assays and inhibition of 1-309 induced chemotaxis assays (Luttichau H R et al. “A highly Selective CC Chemokine Receptor (CCR)8 Antagonist Encoded by the Poxvirus Molluscum Contagiosum J Exp Med 191:171-179, 2000).
[0054] 1. Compositions According to the Present Disclosure
[0055] The disclosure relates to compositions adapted for the treatment of Atopic Dermatitis (AD), other atopic diseases, other inflammatory disorders, Th2 mediated disorders, and CCR8 mediated disorders. These compositions comprise a protein or sequence of amino acids selected from the group consisting of: MC148p1, MC 148p2, MC 148p3, other MC 148p type proteins, MC148fp (fusion protein)1, MC148fp2, MC148fp3, other MC148fp type proteins, and fragments, variants, analogs, or derivatives of these proteins which possess AD inhibiting activity, human skin penetration capacity and/or exhibiting inhibition of chemotaxis and/or function of cells expressing CCR8.
[0056] A. Fragments of MC148p: Fragments of MC148p may be any amino acid sequence which is identical to or sufficiently homologous to MC148p such that AD inhibiting activity, human skin penetration capacity and/or CCR8 blocking activity is/are preserved. These fragments may be generated by genetic engineering, such as of translation stop sites within the coding region. These fragments may be formed using techniques known in the art, such as genetic engineering (e.g. in E. coli , baculovirus, etc.). Such materials may be made as a single peptide, a multimer which may be cleaved. Such materials may be obtained as a secreted material, through lysis of a cell, etc. and may be used directly or may be altered, such as refolded prior to use. Alternatively, treatment of the MC148p with proteolytic enzymes, known as proteases, can produce a variety of N-terminal, C-terminal and internal fragments. Examples of fragments may include contiguous portions of a MC148p of 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25-30, 31-35, 36-40, 41-45, 46-50, 51-55, 56-60, 61-65, 66-70, 71-75, 76-80, 81-85, 86-90, 91-95, 96-100, or more than 100 amino acids in length. These fragments may have primary, secondary (a-helices, n-sheets, or other), tertiary and quaternary structures, including domains and loops.
[0057] These fragments may be purified according to known methods, such as precipitation (e.g. ammonium sulfate), HPLC, ion exchange chromatography, affinity chromatography (including immune-affinity chromatography) or various size separations (sedimentation, gel electrophoresis, gel filtration).
[0058] B. Variants of MC148p: Variants of MC148p for inclusion in the compositions of the present disclosure can be substitution, insertion or deletion variants of MC 148p. Deletion variants lack one or more residues of the native protein which are not essential for function or immunogenic activity, and are exemplified by the variants lacking a leader sequence. Another common type of deletion variant is one lacking secretory signal sequences or signal sequences directing a protein to bind to a particular part of a cell. Insertion mutants typically involve the addition of material at a non-terminal point in the polypeptide. This may include the insertion of an immune-reactive epitope or simply a single residue. Terminal additions, called fusion proteins have already been employed in this disclosure and are further discussed below.
[0059] Substitution variants typically contain the exchange of one amino acid for another at one or more sites within the protein, and may be designed to modulate one or more properties of the polypeptide, such as stability against proteolytic cleavage, without loss of other functions or properties. Substitutions of this kind preferably are conservative, i.e. one amino acid is replaced with another of similar shape and charge. Conservative substitutions are well known in the art and include, for example, the changes of: alanine to serine; arginine to lysine; asparagine to glutamine or histidine; aspartate to glutamate; cysteine or threonine to serine; glutamate to aspartate; glycine or leucine to proline; histidine to asparagine, lysine or glutamine; isoleucine to leucine or valine; leucine to valine; tyrosine to phenylalanine or tryptophan; the reverse of the above changes; other substitutions.
[0060] The following is a discussion based upon changing of the amino acids of a protein to create an equivalent, or even an improved, second-generation molecule. For example, certain amino acids may be substituted for other amino acids in a protein structure without appreciable loss of interactive binding regions of antibodies or binding sites on substrate molecules. Since it is the interactive capacity and nature of a protein that defines that protein's biological functional activity, certain amino acid substitutions can be made in a protein sequence, and it's underlying DNA coding sequence, and nevertheless obtain a protein with like properties. It is thus contemplated by the inventor that various changes may be made in the DNA sequences of genes without appreciable loss of biologic utility or activity.
[0061] In making such changes, the hydropathic index of amino acids may be considered. The importance of the hydropathic amino acid index in conferring interactive biologic function on a protein is generally understood in the art (Kyte & Doolittle, 1982). It is accepted that the relative hydropathic character of the amino acid contributes to the secondary structure of the resultant protein, which in turn defines the interaction of the protein with other molecules, for example, enzymes, substrates, receptors, DNA, antibodies, antigens, and the like.
[0062] Each amino acid has been assigned a hydropathic index on the basis of their hydrophobicity and charge characteristics (Kyte & Doolittle, 1982). These are: isoleucine (+4.5); valine (+4.2); leucine (+3.8); phenylalanine (+2.8); cysteine/cystine (+2.5); methionine (+1.9); alanine (+1.8); glycine (−0.4); threonine (−0.7); serine (−0.8); tryptophan (−0.9); tyrosine (−1.3); proline (−1.6); histidine (−3.2); glutamate (−3.5); glutamine (−3.5); aspartate (−3.5); asparagine (−3.5); lysine (−3.9); arginine (−4.5).
[0063] Certain amino acids may be substituted by other amino acids having a similar hydropathic index or score and still result in a protein with similar biologic activity, i.e. still obtain a biologic functionally equivalent protein. In making such changes, the substitution of amino acids whose hydropathic indices are within +/−2 is preferred, those within +/−1 are particularly preferred and those within +/−0.5 even more particularly preferred.
[0064] The substitution of like amino acids can be made effectively on the basis of hydrophilicity. U.S. Pat. No. 4,554,101, incorporated herein by reference, states that the greatest local average hydrophilicity of a protein, as governed by the hydrophilicity of its adjacent amino acids, correlates with a biologic property of the protein. As detailed in U.S. Pat. No. 4,554,101, the following hydrophilicity values have been assigned to amino acid residues: arginine (+3.0); lysine (+3.0); aspartate (+3.0+11); glutamate (+3.0+/−1); serine (+0.3); asparagine (+0.2); glutamine (+0.2); glycine (0); threonine (−0.4); proline (−0.5+/−1); alanine (−0.5); histidine (−0.5); cysteine (−1.0); methionine (−1.3); valine (−1.5); leucine (−1.8); isoleucine (−1.8); tyrosine (−2.3); phenylalanine (−2.5); tryptophan (−3.4).
[0065] It is understood that an amino acid can be substituted for another having a similar hydrophilicity value and still obtain a biologically equivalent and immunologically equivalent protein. In such changes, the substitution of amino acids whose hydrophilicity values are within +/−2 is preferred, those that are with +/−1 are particularly preferred, and those within +/−0.5 are even more particularly preferred.
[0066] As outlined above, amino acid substitutions are generally based on the relative similarity of the amino acid side-chains, for example, their hydrophobicity, hydrophilicity, charge, size, and the like. Exemplary substitutions that take variants of the foregoing characteristics into consideration are well known to those of skill in the art and include: arginine and lysine; glutamate and aspartate; serine and threonine; glutamine and asparagine; and valine, leucine and isoleucine.
[0067] Another embodiment for the preparation of polypeptides according to the disclosure is the use of peptide mimetics. Mimetics are peptide-containing molecules that mimic elements of protein secondary structure. (See, for example, Johnson et al. “Peptide Turn Mimetics: in Biotechnology and Pharmacy. Pezzuto et al. Eds., Chapman and Hall, N.Y. 1993). The underlying rationale behind the use of peptide mimetics is that the peptide backbone of proteins exists chiefly to orient amino acid side chains in such a way as to facilitate molecular interactions, such as those of antibody and antigen. A peptide mimetic is expected to permit molecular interactions similar to the natural molecule. These principles may be used, in conjunction with the principles outlined above, to engineer second generation molecules having many of the natural properties of MCV type 1, type 2 and other type viral proteins, but with altered and even improved characteristics.
[0068] A specialized kind of variant (terminal addition) is the fusion protein. This molecule generally has all or a substantial portion of the native molecule, linked at the N- or C-terminus, to all or a portion of a second polypeptide. For example, fusions may employ leader sequences from other species to permit the recombinant expression of a protein in a heterologous host. Another useful fusion includes the addition of an immunologically active domain, such as an antibody epitope, to facilitate purification of the fusion protein. Inclusion of a cleavage site at or near the fusion junction will facilitate removal of the extraneous polypeptide after purification. Other useful fusions include linking of functional domains, such as active sites from enzymes, glycosylation domains, cellular targeting signals or trans-membrane regions. The above proteins, fusion proteins, fragments, variants, analogs and derivatives for use in the compositions of the present disclosure can be produced by means of recombinant expression.
[0069] One aspect of the invention provides a fusion protein (e.g. constructed as in FIG. 4B ) to enable penetration of MC148p1 of the index case into skin, such as neonatal foreskin ( FIG. 7A ). This fusion protein has attached to the carboxyl terminal of MC148p1 of the index case the TAT sequence (tyrosine, glycine, arginine, lysine, lysine, arginine, arginine, glutamine, arginine, arginine, arginine or YGRKKRRQRRR (SEQ ID NO: 12)) followed by polyHis (such as 6XHis (histidine, histidine, histidine, histidine, histidine, histidine or HHHHHH)) (SEQ ID NO: 11) at the C-terminus. A 6xHis (SEQ ID NO: 11) provides an antigen for a (biotinylated) antibody; thus penetration of the fusion protein into human neonatal foreskin (or any other tissue or cells) can be proven such as in this instance by biotin streptavidin DAB immunohistochemistry ( FIG. 7A ). While not wishing to be limited to a particular mechanism, the TAT sequence enables penetration. This demonstration is an advance, for example, over the published work of Johnson J L et al. “TAT-Mediated Delivery of a DNA Repair Enzyme to Skin Cells Rapidly Initiates Repair of UV-Induced DNA Damage” J Invest Dermatol 131:753-761, 2011 in that Johnson J L et al. used a human full thickness skin model, Epi-derm FT (Mattek, Ashland, Mass. Such models have been called “human skin equivalents,” but they are not equivalent. Artificial skin constructs have been shown to differ from real skin biochemically and structurally. For example, biochemically the stratum corneum of the artificial constructs studied by Thakoersing V S et al. (J Invest Dermatol 144:59-67, 2013) contains monounsaturated fatty acids, which enhance or induce the formation of hexagonal lateral packing of cornified cells (stratum corneum keratinocytes). Hence, such an artificial skin constructs mainly has a hexagonal packing. Hexagonal packing has been correlated with impaired barrier function, which in turn facilitates penetration of compounds whose penetration differs from penetration of compounds into normal stratum corneum. In addition, commercially sourced artificial constructs may not possess the classic 9 ceramide classes nor the 12 ceramide subclasses more recently identified (Thakoersing V S et al., Bouwstra J A in J Invest Dermatol 133: 59-67, 2013). By contrast normal human skin has a dense orthorhombic packing. The mainly hexagonal packing of artificial skin constructs that may correlate with impaired barrier function may have eased the penetration of the topically applied ˜18 kDa protein studied by Johnson J L et al. referenced above. In contrast with the artificial skin test system used above, normal stratum corneum was used for testing according to the current disclosure, and significant penetration of therapeutic protein was achieved. It was by no means obvious that penetration of normal stratum corneum could be achieved.
[0070] One aspect of the invention described herein is that penetration of a topically applied protein of −15.6 kDa into normal human neonatal skin has been achieved. The C-terminal polyHis (6xHis (SEQ ID NO: 11)) may be retained. The positive charge of the histidine residues may further enhance penetration; further polyHis (e.g. 6x histidine (SEQ ID NO: 11)) may additionally provide a therapeutic benefit. Adult volunteers with AD fed L-histidine orally had a 34% improved SCORAD at the end of 4 weeks of treatment. No side effects were identified (Griffiths C E and Gibbs N K J Invest Dermatol 132:S51, 2012). As described herein, and as applied to the treatment of AD, the histidine residues may be being applied exactly where they are needed. A series of residues may be placed in or at any part of the fusion protein such as at the N-terminal, at the C-terminal, or in the middle of the protein (e.g., for example, between protein domains). The residues may, for example be useful as spacer residues or may provide a more specific benefit based on their composition. In some embodiments, the residues may be acidic residues. The acidic residues may include any number and any type of acidic residues (e.g. histidine residues, lysine residues or arginine residues), alone or in combination and in any pattern (e.g. alternating, random, etc.). 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, from 10 to 20 (inclusive), from 21 to 30 (inclusive) or more than 30 such residues may be added. One or more than one (e.g. 2, 3, 4, or more than 4) such strings may be included in a Molluscum contagiosum fusion protein.
[0071] C. Administration to a Patient: Compositions according to the present invention, for the treatment of AD, other atopic diseases, other inflammatory disorders, Th2 mediated disorders and CCR8 mediated disorders may include one or more pharmaceutically acceptable carriers to provide a pharmaceutically acceptable composition for delivery to a patient. The phrase “pharmaceutically or pharmacologically acceptable” refers to molecular entities and compositions that are unlikely to produce adverse, allergic or other untoward reactions when administered to an animal or a human patient. As used herein, “pharmaceutically acceptable carrier(s)” includes any and all solvents, suspensions, dispersion media, coatings, oils, antibacterial and antifungal agents, preservatives, detergents, emollients, astringents, ointments, creams, lotions, gels, foams; occlusion techniques; iontophoresis, electroporation or other devices; isotonic and absorption delaying agents and the like, including the types of carriers referenced by Smith E W and Maibach H I: “Percutaneous Penetration Enhancers”, CRC Press, 1995, N.W. Boca Raton, Fla. as well as other carriers described in the medical and technical literature. Methods contemplated for delivery of the composition are not limited to chemical penetration enhancers, but also include non-chemical methods such as iontophoresis and electroporation. A composition (e.g. containing a Molluscum contagiosum viral fusion protein as described herein) may be absorbed to, attached to, conjugated to, encapsulated in, or otherwise incorporated into or otherwise connected with another material. Such a material may provide any benefit, such as improved delivery of the composition to the body, reduced toxicity in the body, improved composition stability, etc. Such a material may be chemically neutral, negatively charged or positively charged. A positively charged material, may, in particular, aid penetration of a composition through the skin barrier (stratum corneum). Such a particle may be, for example, a microsphere or a nanoparticle. Such a particle may be less than 1 nm in at least one dimension, less than 10 nm in at least one dimension, less than 100 nm in at least one dimension, from 10 nm up to 50 nm in at least one dimension, from 50 nm up to 100 nm in at least one dimension, from 100 nm up to 500 nm in at least dimension, from 500 nm up to 1000 nm in at least one dimension, or longer than 100 nm or larger in at least one dimension. Such a particle may include any material that improves the composition, such as an alginate, alginate-chitosan, albumin, chitosan, gelatin, another polymer, a silicon particle, etc. In some embodiments, a fusion protein as described herein may be attached to a nanoparticle that is less than 500 nm in at least one dimension. In a particular example, fusion protein (e.g. an MC148fp as described herein) may be attached to positively charged alginate-chitosan nanoparticles which may enable penetration of the composition through the stratum corneum. Preferred pharmaceutically acceptable carriers include sulfoxides such as decylmethylsulfoxide, dimethylsulfoxide, pyrrolidones and combinations of these (Azone), macromolecular microspheres, liposomes and hydrogels.
[0072] Supplementary active ingredients also can be incorporated into the compositions. The use of such carriers and penetration enhancers for pharmaceutically active ingredients is well known in the art.
[0073] The pharmaceutically acceptable compositions of the present invention may include any classical or non-classical pharmaceutical preparation, which includes a MC 148p, a MC148fp or a fragment, variant, analog or derivative of a MC 148p or MC148fp as an active ingredient. Administration of these compositions according to the present invention will be via any common route so long as the target tissue is available via that route. Because the treatment of skin disease is initially contemplated, the route is preferably adapted for the treatment of skin, e.g. a localized delivery, optionally topically or via subcutaneous injection.
[0074] When the composition is delivered topically, the composition is preferably applied directly to the area affected by the skin disease. For subcutaneous or other administration, the most desirable point of delivery need not necessarily be at or near the area affected by the skin disease.
[0075] The pharmaceutically acceptable compositions according to the present invention may include sterile aqueous solutions or dispersions or suspensions for the preparation of sterile injectable solutions or dispersions. The form may be sterile and may be fluid in embodiments where the fluid is to be delivered by injection. The form should be stable under the conditions of manufacture and storage and may be preserved against contamination of microorganisms, such as bacteria, fungi and yeasts. The carrier can be a solvent or dispersion medium containing, e.g. water, ethanol, polyol (such as glycerol, propylene glycol, liquid polyethylene glycol and the like), suitable mixtures thereof, and vegetable or other oils. Proper fluidity can be maintained, by way of example, by the use of a coating, such as lecithin, by the maintenance of the required particle size in the case of dispersion and by the use of surfactants. The prevention of the action of micro-organisms can be brought about by various antibacterial, antifungal and anti-yeast agents, e.g. parabens, chlorobutanol, phenol, sorbic acid, thimerosal, benzalkonium and the like. In many cases, it may be preferable to include isotonic agents, e.g. sodium chloride, phosphate buffered saline or sugars. Prolonged adsorption of the injectable compositions can be brought about by the use in the compositions of agents delaying absorption, e.g. aluminum monostearate and gelatin.
[0076] Sterile injectable solutions may be prepared by incorporating the active ingredients in the required amount in the appropriate solvent with a variety of the other ingredients enumerated above, as required, followed by filtered sterilization. Generally, dispersions may be prepared by incorporating the various sterilized active ingredients into a sterile vehicle which contains the basic dispersion medium and the required other ingredients from those enumerated above. In the case of sterile powders for the preparation of sterile injectable solutions, the preferred methods of preparation are vacuum-drying and freeze-drying techniques which yield a powder of the active ingredient plus any additional desired ingredient from a previously sterile filtered solution thereof.
[0077] The compositions of the present invention may be formulated in a neutral or salt form. Pharmaceutically acceptable salts include acid addition salts (formed with the free amino groups of the protein) which are generally formed with inorganic acids such as hydrochloric or phosphoric acids, or organic acids such as acetic, oxalic, tartaric, mandelic acids and the like. Base addition salts are salts formed with free carboxyl groups as derived from inorganic bases such as sodium, potassium, ammonium, calcium, or ferric hydroxides, and such organic bases as isopropylamine, trimethylamine, histidine, procaine and the like.
[0078] Upon formulation, solutions may be administered in a manner compatible with the dosage formulation and in such amount as is therapeutically effective. The formulations are easily administered in a variety of dosage forms such as injectable solutions, and the like. For parenteral administration in an aqueous solution, for example, the solution may be suitably buffered if necessary and the liquid diluent first rendered isotonic with sufficient saline or glucose. In this connection, sterile aqueous media, which can be employed, will be known to those of skill in the art in light of the present disclosure. For example, one dosage could be dissolved in 1 ml of isotonic NaCl solution and either added to 1000 ml of hypodermoclysis fluid or injected at the proposed site of infusion (see for example, “Remington's Pharmaceutical Sciences” 15 th Edition, pages 1035-1038 and 1570-1580). Some variation in dosage will necessarily occur depending on the condition of the subject being treated. The person responsible for administration will, in any event, determine the appropriate dose for the individual subject. Moreover, for human administration, preparations meet sterility, pyrogenicity, general safety and purity standards such as required by the FDA Office of Biologics Standards.
[0079] 2. Descriptions of FIGS. 5A-8B .
[0080] FIGS. 5A-5B illustrate the clinically demonstrable inhibitory effect of MCV upon a field of AD.
[0081] In FIGS. 5A and 5B the patient (PR) is a light skinned African American man, 16 years of age at the time these photographs were taken. PR had a chronic, widespread, waxing and waning atopic dermatitis (AD). He carried a persistent and heavy infection of Molluscum contagiosum virus (MCV) expressed as numerous light reddish tan, mildly lucent, sometimes umbilicated papules (hillocks) shown on the clinical photographs. The papules consisted of MCV infected epidermal keratinocytes. Many of the papules were ˜5 mm in diameter (range 3 to 7 mm).
[0082] FIG. 5A photograph was taken at a focal distance of 15 centimeters and FIG. 5B photograph at 5 centimeters. FIG. 5A shows a background of AD manifest as mildly scaly, somewhat lichenified, reddish brown skin. Clear zones of clinically normal skin surround each papule of MCV. The clear zones range from 3 to 8 mm in dimension from the edge of a MCV papule to the edge of the background dermatitis. There appears to be a rough correlation between the size of a MCV papule and the width of the clear zone around it. The lack of a direct linear correlation could be associated with colonization of the skin with Staphylococcus aureus (Staph or S. aureus ).
[0083] Staph frequently colonizes the skin of patients with AD and almost invariably exacerbates the dermatitis. PR had culture proven S. aureus skin infections. AD is characterized by the expression of the ligand I-309 (CCL 1) induced recruitment to the skin of cells expressing CCR8. Chemokine ligand 1-309 is not found expressed in normal skin but shows a marked staining within the basal cell layer of the epidermis in patients with AD and is in large measure produced by Langerhans cells and endothelial cells. (Gombert M et al. “CCL1-CCR8 Interactions: An Axis Mediating the Recruitment of T Cells and Langerhans-Type Dendritic Cells to Sites of Atopic Skin Inflammation” J Immunol 174:5082-5091, 2005). The recruited cells include activated Th2 cells, dermal dendrocytes and epidermal Langerhans cells. Serum levels of 1-309 are markedly elevated in patients with severe AD and correlate with numbers of eosinophils in peripheral blood of these patients, suggesting that eosinophils might also express CCR8 (Higashi N et al. in J Invest Dermatol 125:601, 2005), because 1-309 is a specific chemokine for CCR8. (Luttichau H R et al. in J Exp Med 191:171-179, 2000). Indeed the paucity of inflammatory cells, including eosinophils, as well as a dearth of capillaries in the clear zones adjacent to the MCV papules as shown clinically in FIGS. 5A and 5B and microscopically in FIG. 6A suggest that endothelial cells, eosinophils, activated Th2 cells and cells of the monocyte line, including dendrocytes and Langerhans cells all express CCR8 in AD inflamed skin. All of this is aggravated by S. aureus because S aureus induces production of 1-309 from mast cells, dendrocytes and endothelial cells. Further S. aureus exotoxins up-regulate T cell production of the highly pruritogenic IL-31 which is also elevated in patients with AD.
[0084] FIG. 5B shows a photograph of an area of more severe AD in patient PR—an area characterized by a dark gray brown, markedly lichenified skin with prominent scale. Four frank excoriations are demonstrable. (Persons with AD almost always itch and almost always scratch.) In the center of the photograph are 2 MCV papules around which are clear zones of normal appearing skin. Hence the anti-inflammatory effect of MCV is sufficiently powerful to suppress even severely inflamed atopic dermatitis.
[0085] The zone of inhibition around each MCV papule may be viewed as analogous to the zone of inhibition around a penicillin disk on an agar plate streaked with Streptococci. The therapeutic implications are also analogous.
[0086] FIGS. 6A-6B illustrate the microscopically demonstrable inhibitory effect of MCV upon a field of AD. The photomicrograph of the biopsy depicted in FIG. 6A was taken from an area of atopic dermatitis on the skin of PR immediately adjacent to a papule of MCV. The edge of the papule is seen on the lower left, and within the expanded lower spinous cell layer of the papule, the cytoplasm of the keratinocytes contains Molluscum bodies, visible on light microscopy as deposits of eosinophilic amorphous material. The top of the photomicrograph shows the base of the adjacent epidermis. Moderate numbers of fibroblasts are found in a modified connective tissue around the Molluscum papule. A paucity of mononuclear cells is found around sparse small capillaries in the upper part of the dermis adjacent to the Molluscum papules. There is a mild to moderate acanthosis, seen here in the lower part of the epidermis. Scant is the inflammatory infiltrate within the connective tissue in the region of the Molluscum papule, extending far laterally into the papillary and reticular parts of the dermis. The lack of inflammation in the dermis adjacent to the Molluscum papule resembles the appearance of normal skin. (H&E, 100).
[0087] The photomicrograph of the biopsy depicted in FIG. 6B was taken concurrently (the same date and time) from a similar area of AD on the skin of PR remote from the Molluscum papules grouped and scattered on his skin. The top of the photomicrograph shows a markedly acanthotic epidermis with a central adherent crust denoting a site of excoriation, due to incessant itching characteristic of AD. The itching, in turn, is secondary to inflammatory mediators of diverse origin—many of which are the products of the inflammatory cells which infiltrate the skin of patients with AD. The moderate to marked, predominantly lymphohistiocytic infiltrate is seen here not only around the blood vessels of the superficial plexus, but also around vessels of the upper reticular dermis serving that plexus and around vessels of the papillae. The infiltrate of inflammatory cells extends into the interstitium. Inflammatory cell epidermotropism is also present. (H&E, 100×). At higher magnification, eosinophils can also be seen within the inflammatory infiltrate on this photomicrograph.
[0088] FIG. 7A illustrate the penetration of MC 148 fusion protein (MC148p-TAT-6xHis (“6xHis” disclosed as SEQ ID NO: 11)) through the stratum corneum of normal neonatal skin and its accumulation along the basal cell layer. Lighter deposits of MC148p-TAT-6xHis (“6xHis” disclosed as SEQ ID NO: 11) are seen in the stratum corneum and elsewhere in the malpighian layer. Penetration was achieved using concentrations as low as 3 μg of fusion protein in 100 μL of phosphate buffered saline (PBS), applied in separate experiments in aliquots of 20 μL and later 10 μL to be sure that no solution seeped around the edges of the neonatal foreskins to the undersurfaces. Concentration of 30 μg in 100 μL of PBS enabled penetration of MC148-TAT-6xHis (“6xHis” disclosed as SEQ ID NO: 11). The use of higher and lower concentrations is not excluded. For example, from 0.1 μg up to 1 μg, from 1 μg up to 5 μg, from 2 μg up to 4 μg, from 5 μg up to 10 μg, from 10 μg up to 50 μg, from 50 μg up to 300 μg, or more than 300 μg, in 100 μL of PBS may be used.
[0089] FIG. 7B illustrates both positive and negative controls. Anti-Collagen 1A antibody tagged with biotin was applied to the foreskins in the process of standard immunohistochemical procedure giving the positive control whereas anti-His antibody tagged with biotin was not used providing the negative control.
[0090] Neonatal foreskins were chosen for penetration studies because their properties approximate the properties of atopic dermatitis (AD) lesional skin. Both neonatal skin and AD skin have low hydration and are susceptible to irritants and allergens. The concentration of natural moisturizing factor is significantly lower in neonatal and AD skin than in normal human adult skin. Two key enzymes of lipid processing to form ceramides (β-glucocerebrosidase and acid sphingomyelinase) do not have the required acidic pH for optimal activity, resulting in impaired formation of ceramides in neonatal stratum corneum and defective barrier function. Further the neutral to alkaline pH of neonatal skin amplifies the activity of serine proteases (kallikreins 5 and 7) which block lamellar body secretion of stratum corneum lipids, further impairing barrier function (Fluhr J W in Br J Dermatol 166:483-490, 2012). These impairments are also characteristic of lesional skin of AD.
[0091] MC148p inhibits 1-309 induced chemotaxis of cells expressing CCR8 at very low concentrations (IC50 2 nM). However, MC148p shows no penetration of neonatal stratum corneum after repeated attempts. The McCullough group achieved penetration of their Chlorella virus-pyrimidine-dimer-glycosylase by attaching a nuclear localization sequence (NLS) and a transcriptional transactivator peptide (TAT) derived from the human immunodeficiency virus, yielding a fusion protein whose molecular weight was ˜18 kDa (Johnson J L, see below). For penetration studies the McCullough group (Johnson J L, as below) used a synthetic commercially available full thickness human skin model, Epi-derm FT (Matttek, Ashland, Mass.), and by fluorescent probes showed penetration of Cv-pdg-NLS-TAT into the skin model, with its accumulation along the basal cell layer. (Johnson J L, Lowell B C, Ryabinina O P, Lloyd R S and McCullough A K “TAT-Mediated Delivery of a DNA Repair Enzyme to Skin Cells Rapidly Initiates Repair of UV-Induced DNA Damage” J Invest Dermatol 131:753-761, 2011).
[0092] A therapeutic protein characteristically targets (only) the extracellular space. In order to deliver a therapeutic protein further, a specific arginine-rich protein transduction sequence from antennapedia, TAT, VP22, etc. was used to deliver proteins into cells by attaching the arginine-rich transporter peptides to cysteine groups within such proteins. Success of this delivery method was shown by biologic effects such as induction of apoptosis by delivery of caspase-3 (Siprashvili Z, Reuter J and Khavari P in J Invest Dermatol 122: A51, 2004). Fluid phase endocytosis was shown to be “the” mode of cellular entry of the protein transduction domain of TAT (Gump J M, Dowdy S F in Trends Mol Med 13: 443-8, 2007). This approach is not germane to skin barrier penetration which is described herein. For example, fluid phase endocytosis is very different from the delivery of a protein through the stratum corneum, as described herein.
[0093] The stratum corneum is a dead, tough and resistant skin barrier making up the outer layer of the skin. It separates and protects underlying tissue from environmental factors, such as bacteria, other infectious agents, chemicals, debris, toxins and (other) proteins. It also provides a barrier to prevent a desired therapeutic agent from entering the body. It is not a cell membrane (e.g. it is not a cell in the interstitial fluid) but rather it is a compact barrier of lipid and keratin. Classically unaided absorption of molecules through the stratum corneum barrier of intact human skin is limited to molecules smaller than about 500 Da (Bos and Meinardi, Exp Dermatol 9:165-169, 2000) and favors lipophilic compounds. Hydrophilic drugs penetrate the stratum corneum poorly or not at all, presumably due (at least in part) to the lipophilic properties of the stratum corneum. For example, Gobel A, Schmaus G, Wohlrab J et al., J Am Acad Dermatol. 60: AB82, 2009) describes achieving penetration of a peptide consisting of 2 amino acids through the stratum corneum using 5% 1, 2 pentanediol to increase the penetration of the dipeptide carnosine. By contrast, this disclosure demonstrates penetration of a peptide consisting of 121 amino acids with a molecular weight approximating 15.6 kDa.
[0094] Challenges in treating a body (such as the skin) with a topical compound may include determining a useful therapeutic agent, generating a useful (active) therapeutic agent, maintaining the agent's stability (e.g. ensuring a useful shelf life), and delivering (e.g. applying) the agent to the body such as to the skin. Additional challenges may include transporting the agent across the stratum corneum, such as by passively diffusing it across the stratum corneum (such as allowing it to diffuse) or by actively transporting it (such as using an electric field or electric current). Further challenges may include delivering the agent through the interstitial fluid (such as to a cell), moving the agent to the outside of a cell, moving an agent across the cell membrane, and effecting a change by the agent (e.g. by maintaining a therapeutic activity or activating a therapeutic activity), such as on a molecule or a cell. Further challenges may include enabling the treatment in an individual with an abnormal skin composition (e.g. an altered barrier composition such as in an atopic dermatitis patient) or an altered immunological state. In addition to needing to overcome such obstacles, the behavior of a given peptide or protein varies widely from another peptide or protein in the same environment. The behavior of a single peptide or protein varies from one environment to another, making it difficult to predict based on the behavior of one protein type how another protein will behave. Such differences may be obvious or may be seemingly small that nonetheless control the protein's behavior in any given environment as exemplified by such variables as overall length, folded size, overall charge, hydrophobicity or hydrophilicity, local or domain charge, hydrophobicity or hydrophilicity, the particular cell type or extracellular environment. For example, Wolf P., Yarosh D., and Kripke M L (J Invest Dermatol 114: 149-56, 2000) used liposomes to encapsulate the viral nucleic acid repair enzyme, T4 endonuclease V which is approximately 16.5 kDa. Encapsulating biotinylated MC 148 protein in liposomes following the Yarosh method achieved about 90% encapsulation efficiency. However, neonatal foreskin experiments with MC 148 protein in PBS did not show penetration. Yarosh enhanced delivery of the proteinated liposomes in a specific hydrogel called Hypan S S 201 (Vladimir Stoy and Charles Kliment); however, Hypan S S 201 is no longer available. Such approaches could not be readily used to deliver MC 148 to the cells of interest.
[0095] One aspect of the invention, such as illustrated in FIG. 7A , is a hydrophilic fusion protein (MC 148p-TAT-6xHis (“6xHis” disclosed as SEQ ID NO: 11)) weighing ˜15.6 kDa that penetrates the intact skin barrier (including the stratum corneum) of normal human neonatal skin. This is both new and unexpected. There are significant differences between the work done by the McCullough group and the subject of this disclosure. In addition to using different protein/peptide sequences, different targets, etc. in the McCullough fusion protein, the TAT penetration enabling sequence was positioned at the carboxyl terminus of the protein, whereas as described in some embodiments of the disclosure herein, the TAT sequence is separated from the carboxyl terminus by histidine residues (e.g. by 6 histidine residues (SEQ ID NO: 11), to form an MC 148p-TAT-PolyHis protein. The McCullough group used an artificial skin construct. Such constructs have been called “human skin equivalents,” but they are not equivalent. Artificial skin constructs have been shown to differ from real skin biochemically and structurally. Artificial constructs contain monounsaturated fatty acids, such as oleic acid possessing one double bond, which enhance the formation of hexagonal lateral packing. As mentioned, these artificial skin constructs have been shown mainly to display hexagonal packing, which corresponds to impaired barrier function (Thakoersing V S et al. in J Invest Dermatol 133:59-67, 2013). By contrast, normal human skin contains primarily polyunsaturated fatty acids such as linoleic acid possessing 2 double bonds which correspond to a dense orthorhombic packing and normal barrier function. The histidine (e.g. 6xHis (SEQ ID NO: 11)) does not appear to substantially interfere with passage of MC 148p-TAT into the skin. It rather may enhance penetration through the stratum corneum, perhaps due to its positive charge. In addition to this, polyHis may have therapeutic advantage in the treatment of AD independent of the anti-inflammatory action of the MC148 portion of the fusion protein. Adult volunteers with atopic dermatitis fed L-histidine orally had alleviation of their atopic dermatitis as demonstrated by a 34% improved SCORAD at the end of 4 weeks and a 19% reduction in transepidermal water loss (TEWL). No side effects were identified (Griffiths C E and Gibbs N K J Invest Dermatol 132:S51, 2012).
[0096] FIG. 8A illustrates that 1-309 induced chemotaxis is inhibited by recombinant MC148 protein with an IC50 at ˜2 nM whereas synthetic MC 148 protein fails to obtain an IC50 even at 15,000 nM. FIG. 8A also shows that the peptide fragment VL-10 consisting of amino acids VSLARRKCCL (SEQ ID NO: 13) and encompassing the binding site of MC148p also fails to obtain an IC50 at 15,000 nM. Finally FIG. 8A shows that a mix of all synthetic peptides tested—all encompassing the binding site of MC148p—had a negative inhibitory effect, i.e. behaved in a manner to exacerbate inflammation. The composition of the mix of fragments was as follows: VL-10 as above, PP-20 consisting of amino acids PRPGVSLARRKCCLNPTNRP (SEQ ID NO: 14), MP-38 consisting of the first 38 amino acids starting from the N-terminus (see FIG. 1B ) and VV-54 consisting of the 54 amino acids starting with a valine at position 23 and extending to the valine at position 76 (see FIG. 1B ). These results also inform that the entire recombinant protein may be especially effective in achieving an inhibitory (anti-inflammatory) effect. The fragments tested and the synthetic 104 amino acid synthetically made protein lack the proper folding required for biologic effect.
[0097] The biological effect (e.g. functionality or activity) of adding one or more than one domain to a protein is unpredictable. It was unclear whether a protein comprising an MC 148 protein, a TAT portion and a polyHis portion would remain functional, such as on chemotaxis assays. In particular, it was predicted that the positive charges of both the TAT sequence and the 6xHis sequence (SEQ ID NO: 11) added to the MC148 protein could interfere with the positive charges of the two arginines and the one lysine at positions 27, 28 and 29 respectively of MC 148 protein (i.e. the sites at which MC 148 protein binds to CCR8 expressing cells to have a therapeutic effect). FIG. 8B illustrates that 1-309 induced chemotaxis is inhibited by recombinant MC148p-TAT-6xHis (“6xHis” disclosed as SEQ ID NO: 11) with an IC50 at ˜200 nM. This inhibitory capacity may be compared with that of MC148p suggesting that the positively charged amino acids of TAT and 6xHis (SEQ ID NO: 11) at the carboxyl terminal may have partially interfered with the binding of the native recombinant MC148p to the receptor site of CCR8 near the amino terminals of both proteins. Yet MC148p-TAT-6xHis (“6xHis” disclosed as SEQ ID NO: 11) enables topical delivery which the unmodified MC148p does not. It is noted that the fusion protein (MC148p-TAT-6xHis (“6xHis” disclosed as SEQ ID NO: 11)) remains an effective inhibitor of cells expressing CCR8, albeit at higher but attainable concentration and is therefore suitable for functional testing in vivo.
[0098] As for additional details pertinent to the present invention, materials and manufacturing techniques may be employed as within the level of those with skill in the relevant art. The same may hold true with respect to method-based aspects of the invention in terms of additional acts commonly or logically employed. Also, it is contemplated that any optional feature of the inventive variations described may be set forth and claimed independently, or in combination with any one or more of the features described herein. Likewise, reference to a singular item, includes the possibility that there are plural of the same items present. More specifically, as used herein and in the appended claims, the singular forms “a,” “and,” “said,” and “the” include plural forms unless the context clearly dictates otherwise. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as “solely,” “only” and the like in connection with the recitation of claim elements, or use of a “negative” limitation. Unless defined otherwise herein, 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. The breadth of the present invention is not to be limited by the subject specification, but rather only by the plain meaning of the claim terms employed.
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Compositions, methods, and kits are provided for treating CCR8 mediated diseases with applicability to atopic dermatitis and potential applicability to asthma, prurigo nodularis, nummular dermatitis, neurodeimatitis, and lichen simplex chronicus and some lymphomas, multiple sclerosis, acquired immunodeficiency disease, peritoneal adhesions, Kaposi's sarcoma and atherogenesis—the expression of all of which, at least in part, is mediated by cells expressing the chemokine receptor CCR8. The compositions include proteins and fusion proteins from Molluscum contagiosum Virus (MCV) or variants, analogs and derivatives thereof which exhibit inhibitory activity. Examples of such MCV proteins are MC 148 fusion protein (MC148fp) identified as MC148P-TAT-6xHis (“6xHis” disclosed as SEQ ID NO: 11), and its variants, fragments, analogs and derivatives which possess inhibitory activity. The variants, fragments, analogs and derivatives of MC148p and of MC148fp may be less than 100% homologous to MCV proteins as long as they are sufficiently homologous that inhibitory activity is preserved.
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BACKGROUND OF THE INVENTION
In mining and tunnel construction, the tunnels generally are formed by means of drilling or blasting, or with the aid of various types of cutting machines. During such tunneling it is often unavoidable for the working faces to become larger than the useful and/or desired cross sections, especially in cases where the rock being worked is not compact. Therefore, for reasons of safety and in order to maintain the predetermined useful cross section, the driven tunnels generally are provied with a support or lining. When such supports are utilized it is necessary for the hollow space between the elements of the support and the solid rock of the working faces to be filled in, in order to prevent rock movement and to transfer the rock pressure evenly to the support.
The filling in of the hollow spaces between the working faces of the tunnel and the support may be accomplished in a variety of ways. For example, after a support has been constructed from sheathing of timber, metal sheets, meshed wire, concrete slabs or the like, the hollow space remaining between the support and the working faces of the tunnel may be packed with loose rocks obtained during the tunneling operation. Another known technique comprises filling the space between the sheathing elements of the support and the rock face with concrete or some other quick setting building material. Still another technique, known as the Torkret process, requires less of a material expenditure and merely comprises the application of a several centimeter thick layer of sprayed concrete (gunite) to the rock-face of the tunnel after blasting, whereby the inherent bearing strength of the rock is increased.
According to a more recent technique, plastic hoses are inserted between the rock face and the sheathing, which in this case consists of meshed wire mats disposed on timber support elements. A liquid plastic foam material is then pumped into the hoses and permitted to solidify. In this manner the hollow spaces between the rock face and the support are filled with a cushion formed by the foam-filled hoses.
The demands to be made of this foam-filled hose cushion however, are extremely critical. First of all the hose must be made from a material which can satisfy the requirements for the protection of the miners, for example, with respect to flame resistance and electrical conductivity. The hose material also should be harmless with regard to the health of the miners; for example, it should not result in the formation of any harmful decomposition products. The hose material, furthermore, must have a capacity for extension such that the cushions, developing during filling, will completely fill all hollow spaces, thereby preventing the escape of any accumulations of mine gasses, which escape from the rocks. In addition, the hose material must exhibit an acceptable ductility and tear resistance so that the hose will be able to absorb an operating pressure of at least about 5 bar without tearing. The hoses must also exhibit a resistance to piercing which is as high as possible since the hoses are to be used in conjunction with sheathing of wire or the like which often contains projecting points or edges. At the same time, a high strength against continued tearing is desirable so that minor damage to the skin of a hose will not become the starting point for extensive tears. Finally, one should expect from the hose material, that it will hold the compressed plastic foam together so strongly, that the resulting cushions, despite the relatively low resistance to pressure of the unsupported plastic foam, will absorb relatively high pressure loads and will be capable of transferring such loads to the tunnel support. The hose materials used in the prior art have not fulfilled the above noted requirements, or at least not all of them.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide plastic hoses for filling the hollow spaces between the rock face of a mine or tunnel and the support therefor, which hoses will overcome the disadvantages of the prior art.
It is another object of the invention to provide a process for filling the space between the working faces of a mine or tunnel and the support therefor which will overcome the difficulties and deficiencies of prior art processes.
These and other objects and advantages are accomplished in accordance with the present invention by providing plastic hoses which are characterized by consisting of a high pressure polyolefin, particularly polyethylene, to which has been added suitable flame retarding and antistatic agents, and which exhibits a lengthwise and widthwise resistance to tearing of at least 15 N/mm 2 , a lengthwise and widthwise tear-extension of at least 450%, a resistance to piercing of at least 1.5 J, and a continued tearing resistance of at least 17 N/mm.
Among the flame retarding agents suitable for addition the hose material according to the invention, there may be listed all of the halogenated hydrocarbons known for their flame retardant characteristics, particularly the halogenated aromatic compounds such as the highly brominated aromatic compounds. Decabromo diphenylether is an example of one such brominated aromatic compound. Other suitable flame retardants include inorganic compounds such as antimony trioxide. Mixtures of various flame retardants, such as a mixture of decabromo diphenylether and antimony trioxide have been found to be particularly suitable.
The hoses may be rendered antistatic by the addition of known agents such as graphite powder, metal powders and the like. In one preferred embodiment, the antistatic properties of the hoses may be accomplished by imprinting the hoses, for example, in the shape of a grid using a conductive soot-containing dye.
By using the plastic hoses of the invention, the work of filling the hollow spaces between the rock face of tunnels and the support therefor in mining operations, as well as in case of tunnel construction, may be considerably simplified. However, filling the entire space between the support and the rock face with foam-filled hoses is not always completely satisfactory since the low pressure resistance of the filler material can not prevent rock movements or the absorption of such movement in every case. Moreover, it has been found to be desirable if not necessary to use light-meshed sheathing mats in order to prevent a pressing through and tearing of the foam-filled hoses.
Thus, even greater advantages are attained by using the plastic foam-filled hoses of the invention in conjunction with a process for filling of hollow spaces between the rock face and the tunnel support with a building material which exhibits substantial compressive strength, such as concrete or mortar. This process involves converting the support sheathing with flat webs or sheets of plastic film material, which preferrably correspond in length to the length of the lift or support periphery, inserting the hoses to be filled with foam in the length of the tunnel periphery and parallel to the direction of the webs of plastic film material, filling the hoses with foam material and then filling the hollow space between the foam-filled hoses and plastic film material with a setting or hardening building material.
The invention will be understood more fully in view of the following detailed description thereof, particularly when taken in conjunction with the drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic cross-sectional view illustrating a fully supported tunnel;
FIG. 2 is a schematic cross-sectional view taken along line 2--2 of FIG. 1 illustrating the manner in which the space between the support structure and the rock face is filled, the view depicting a portion of the space running parallel to the axis of the tunnel; and
FIG. 3 is a perspective, schematic view of an air-tight plastic hose having suitable valve means through which a compressed gas may be introduced into the hose to thereby inflate the same.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, there is shown in FIG. 1 a tunnel 10 which is supported by a structure designated generally by the numeral 11. The support structure 11 is comprised of timber or other suitable support elements 12 on which are placed a plurality of sheathing elements 13, such as wire mesh webs. As shown in FIG. 2, the sheathing elements 13 may be arranged over the support elements 12 in a staggered fashion and may have their ends 14 turned down slightly to help keep them in place. A plurality of relatively narrow, elongated sheathing mats or plastic sheets 16 are positioned over the sheathing elements 13 preferably such that the longitudinal edges 17 of adjacent sheets 16 overlap. The sheets 16 preferably are of a length sufficient to traverse the entire periphery of the support structure 11, and optionally, may be bent back at their opposite ends 18, 19 to define grooved or channel-like area adjacent the rock face 21 at the tunnel floor 22.
The hollow space between sheathing and rock face, as well as the channel-like area adjacent the tunnel floor is filled with the building material 23. In FIG. 2, a sectional view through the support structure 11 along the intersecting line 2--2 of FIG. 1 is shown, which view runs parallel to the axis of the tunnel. In this figure, not only is there shown the deposition of the sheathing elements 13 relative to the support elements 12 and the overlapping plastic sheets 16, but there is shown the foam-filled plastic hoses 24 and the building material filler 23 as well. As discussed above, the longitudinal direction or axis of the hoses 24 is parallel to the longitudinal direction of the plastic sheets 16 and each hose 24 generally is of a length sufficient to extend the entire periphery of the support structure 11. While the number and size of the hoses 24 traversing the length of the tunnel may vary, depending, at least in part, upon the length of the periphery of the support structure 11, it is preferable that at least one length of hose 24 be used for each length of plastic sheet 16. As illustrated in FIG. 2, it is also preferred that a length of hose 24 be disposed at least over each overlapping edge 17 of adjacent plastic sheets and that the hose be of a size such that when filled with foam material the hoses contact both the plastic sheets 16 and the rock face 21 and define a seal which is capable of preventing the escape of any accumulated gases.
In order to carry out the process of the invention, a first web or sheet 16 of flat plastic film material is placed directly on the sheathing elements 13 such that the sheet extends from the tunnel floor on one side of the tunnel, up, over and down the entire circumference or periphery of the support structure 11, and to the floor on the other side of the tunnel. As indicated above, the sheet 16 may be bent over at each end 18, 19 to define a channel-like area for receiving the filling material 23. Next, a second sheet 16 is placed over the sheathing elements in the same manner as the first sheet, preferably, so that the edge of the second sheet overlaps the edge of the first sheet. This procedure is continued until a sufficient number of sheets 16 have to be placed on the sheathing elements to cover a predetermined depth of the tunnel support. Next, after removing any loose rock and adjusting the sheets 16, the hollow plastic hoses of this invention are put in place over the sheets 16, the hoses being generally of the same length as the sheets 16 or as the tunnel periphery. Subsequently, the hoses are foamed in a manner known per se, for example, with plastic foam until a tight closure is produced between the plastic sheets 16 and the rock face 21. The remaining hollow space between the sheets 16 and the rock face 21 is then filled with the building material filler 23, for example, by means of a filler hose (not shown) guided through, above, or below the foam-filled hose seals. In this manner, the hollow space between the sheets 16 and the rock face 21 is filled completely with a suitable substance, for example, a concrete mixture. When the filling of the hollow space is finished, the filler hose is removed and any apertures formed in the foam-filled hoses by the filler hose are closed.
Although the above method of operation considerably simplifies and accelerates the filling of the hollow spaces between the support structure and the rock face, an even greater simplification may be achieved by inserting air-tight plastic hoses 26 (FIG. 3) provided with a fill-up valve means 27 into the spaces to be filled and by subsequently inflating them up, for example, with compressed air. Such hoses, for the purpose of adaptation to the various hollow spaces to be encountered, may be produced in a variety of shapes and sizes, and may be characterized, for example, by various color codings to facilitate their selection for a particular end use.
The blowing up or inflation of the hoses 26 may be accomplished most simply by means of compressed air, which may be taken from the compressed air supply normally associated with mining and tunnel construction by means of a conventional pressure reducing valve. After reaching a filling pressure of about 0.05 to 0.1 bar, the hoses 26 generally will fit tightly against the rock face 21 and at the same time against the support structure 11, so that the support structure is guyed solidly with the rock face. Should the rock pressure increase after some time at individual places, a slow escape of the excess pressure developed in the hoses 26 could be made possible by an excess pressure relief valve 28 suitably attached to each hose. In such case the air within each hose 26 would be vented until the rock fits against the support structure and the rock pressure is absorbed directly thereby. Thus, it will be appreciated that the use of hoses filled with compressed air makes possible a quick filling up of the hollow spaces between the rock face and support structure. Such use also insures the working space against ripping of rocks and prevents, moreover, the accumulation of explosive gasses. However, as against the rock pressure, hoses filled with compressed air often are too flexible. This disadvantage may be avoided, however, by using the compressed air only as a temporary means for expanding the hoses 26. Thus, after advancing the support structure 11 a predetermined depth into a mine or tunnel, say 10 to 50 meters, the air in the hoses 26 may be removed by means of valve 27 and replaced by foam material or building materials of a higher compressive strength.
According to this latter method of operation, the hoses 26 are first inserted behind the support structure 11, for example, by rounds of shots in a known manner, in such numbers and sizes as required. The hoses are then filled with compressed air, the space behind the support thus being filled with the hose cushions or seals. This work may be carried out quickly and with minimal apparatus. As soon as the rock face has moved forward into the tunnel by about 10 to 50 meters by the progress of the tunneling operation, the compressed air filling in the hoses 26 near the entrance of the tunnel, is replaced according to the invention, by a filling of foam material or with building materials of a higher compressive strength. By continually proceeding into the tunnel in this manner, the working space for the change of fillings lies far enough behind the work front so that the two jobs will not impede each other either temporarily or with regard to a need for space for the required working apparatus and materials. In this manner, a depth of about 10 to 50 meters having a support filled by air cushions is succeeded by a support having hoses filled by solidified foam or building materials.
Substances, which after a certain time set into a compact mass, are suitable as building materials for use in the present invention, among such materials may be included foamed plastics, such as for example, urea-formaldehyde resins, as well as concrete, mortar or other conventional inorganic settable materials. Foamed plastics, such as urea-formaldehyde resins, may be employed as the foam material for use in the present invention.
There are a number of ways in which the air-filled hose 26 can be filled with the building material. For example, the filling may take place by way of the valve means 27 provided for the filling with air. In such cases, an aperture is formed in the hose 26 to allow the air to escape while a suitable filling hose induces the building material through the valve means 27. It is also possible, to equip the hoses with a second valve means 29, so that the air within the hose will escape only at the rate that it is displaced by the building material. In this manner, the hollow space always remains completely filled by the hose cushion. Another technique comprises piercing the hoses 26 with an appropriate lance and then introducing the building material through the resulting aperture.
It is to be understood that the above-described embodiments are simply illustrative of the principles of the invention. Thus, although the invention has been described in connection with various hose means, per se, and several specific techniques for using such hose means for filling and sealing the space between the rock face of a mine or tunnel and the structure for supporting the same, it is to be understood that the uses of such hose means are not so limited and they may be employed for other applications as well. Moreover, various other modifications and changes may be devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope of the following claims.
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Plastic hose means, preferably of high pressure polyethylene admixed with a flame retarding agent and treated to render the same antistatic and characterized by a resistance to tearing of at least 15 N/mm 2 , an extension of at least 450 percent, a resistance to piercing of at least 1.5 J and a resistance to continued tearing of at least 17 N/mm, are disclosed, as is a process for using the hose means for filling the space between the rock face of a mine or tunnel and the supporting structure therefor.
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BACKGROUND OF THE INVENTION
This invention generally relates to the field of mobile equipment for digging trenches.
In construction and landscaping work it is frequently necessary to dig trenches with walls at angles which vary from the vertical, and many times it is desirable to form a trench wherein each of the side walls thereof are at different angles from the vertical. While there are many prior art devices form trenches with angled side walls, many are inconvenient to use and, none provide any capability of varying the angle to suit the particular needs of a situation. Typical prior art devices for forming trenches with inclined side walls are shown in the following references:
U.S. Pat. No. 2,480,656 (Jenne),
U.S. Pat. No. 2,972,425 (Anderson, et al.),
U.S. Pat. No. 3,003,264 (Shore),
U.S. Pat. No. 3,792,539 (Clark).
In the Jenne, Shore and Clark references the side walls of the trench are formed by a blade or wing which are attached to the front or leading edge of a backhoe or drag line bucket. In the Anderson, et al. reference the bucket is provided with fixed, angled sides which form the sloping walls of a trench. None of the described devices are provided with means to adjust the angle of the side plate of the bucket.
Other references relating to backhoes or drag line buckets for forming trenches which may be of interest are U.S. Pat. No. 3,089,261 (Flath) and U.S. Pat. No. 3,286,377 (Long) which describe wing-like devices attached to the vertical side walls of the bucket to change the cross-sectional shape of the trench. However, no attempt is made to change the angle of the side wall.
For other prior art devices showing a scraping type action for the removal of dirt and the like, reference is made to the following references:
U.S. Pat. No. 2,261,874 (Cundiff),
U.S. Pat. No. 2,556,592 (Markkula),
U.S. Pat. No. 2,662,311 (Chattin),
U.S. Pat. No. 2,673,409 (Briscoe),
U.S. Pat. No. 2,856,709 (Brockly).
U.S. Pat. No. 3,526,047 (Roessler, et al.)
These references primarily are directed to devices having blades which scrape or plow the ground. They do not involve a trench forming type of bucket.
From the above, it is clear that the need remains for a bucket for a trenching device which can form trenches with walls of varying slope and, particularly, a device which can readily vary the slope to meet the particular job requirements without significant modifications to the bucket or the need to replace buckets for particular angled walls. The present invention satisfies this need.
SUMMARY OF THE INVENTION
This invention relates to an improvement in trench-forming equipment such as backhoe tractors, drag lines and the like and, particularly, to buckets for such trenching equipment in which the side plates can be adjusted to form trenches with walls having varying slopes.
In accordance with the present invention an open top bucket is provided with adjustable side plates which are hinged so that the angle of the side plates with respect to the vertical can be readily changed by pivoting the side plates about the axis of the hinged connection. Where the trench is to have a V-shaped cross-section the side plates are hingedly connected together along their lower edge. In those situations where the cross-sectional shape of the trench is to be trapezoidal, the bucket is provided with a floor plate and the side plates of the bucket are hingedly connected along the edges of the floor plate. The bucket is provided with a back wall which is preferably sectioned with the outer sections fixed to the trailing edge of the side plates and fan-shaped in order to form a continuous back wall notwithstanding the inclination of the side plates.
The bucket is provided with means to adjust the inclination of the side plates thereof and, preferably, individual jacks are provided for each side plate so that the angle of each can be separately adjusted as desired.
The backhoe or drag line having a bucket in accordance with the invention is operated in a conventional manner. The only difference is varying the angle of the side plates to form a trench having the desired shape. If desired, hydraulic control means can be provided to adjust the angle of the side plates and the hand controls for such control means may be conveniently provided along with the other operational controls in the operator's console for the backhoe or drag line so that the angle of the side wall can be adjusted as necessary by the operator during the formation of the trench without dismounting from the vehicle.
These and other advantages of the invention will become apparent from the following detailed description when taken in conjunction with the accompanying exemplary drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an embodiment of the invention which is designed for forming V-shaped trenches.
FIG. 2 is a rear view of the bucket shown in FIG. 1.
FIG. 3 is a side view in section taken along the lines of 3--3 shown in FIG. 2.
FIG. 4 is a sectional view of the back wall of the bucket taken along the lines 4--4 shown in FIG. 2.
FIG. 5 is a sectional view of the center portion of the bucket taken along the lines of 5--5 shown in FIG. 3.
FIG. 6 is a plan view, partially in section, of the bucket taken along the lines of 6--6 shown in FIG. 2.
FIGS. 7 and 8 illustrate the cross-sectional shape of trenches formed with the bucket shown in FIGS. 1-6.
FIGS. 9 and 10 are respectively front and rear views of a modified bucket provided with a floor plate.
FIGS. 11 and 12 illustrate the cross-sectional shape of trenches formed with the bucket shown in FIGS. 9 and 10.
DETAILED DESCRIPTION OF THE INVENTION
Reference is made to FIGS. 1-6 which illustrate a bucket 10 embodying features of the invention. As is shown in these drawings, the bucket 10 is pivotally connected to the end of a boom or, more specifically, the dipper stick 11 (shown in phantom in FIG. 1) of a tractor-mounted backhoe (not shown) or other similar trenching equipment. The pivotal connection with bucket 10 is made by means of a yoke 12 and a pin 13 which passes between the upstanding ears 14 and 15 of the yoke 12 and the end of the dipper stick 11. The bucket 10 is rotated about the axis of the pin 13 by means of an operating rod 16 which is pivotally connected by pin 17 to the upstanding ear 18 mounted on the upper member or hanger base plate 20 of the support frame 21. The rod 17 is the operative element of a fluid actuated cylinder (not shown) which forms part of the operative mechanism of the backhoe.
The bucket 10 generally comprises a pair of matching side plates 22, which are pivotally connected along the mating edges thereof by means of a hinge 23, a sectioned back wall 24 and a support frame 21 which includes the hanger base plate 20, struts 25 and 26, a hinge bar 27, and a pair of jack elements 28 which are utilized to adjust the orientation of the side plates 22 about the axis of the hinge 33. The jack elements 28 generally comprise a female member 30 which is pivotally connected by means of bracket 31 and pin 32 to the inside surface of the side plate 22, and a male member 33, internally mounted to female member and threaded on the exterior thereof, which is pivotally connected to the end of the yoke 12 by means of a bracket 34 and a pin 35. A threaded collar 36 with a handle is provided for adjusting the movement of the male member 33 with respect to the female member 30 to thereby adjust the orientation of the side plate 22 about the axis of the hinge 23.
The back wall 24 of the bucket 10 is sectioned and, preferably each of the sections overlap and are fan-shaped so that the wall remains continuous, notwithstanding the occluded angle between the side plates 22. As shown in FIG. 2, each of the outside sections 40 are fixed to or are integrally formed with the adjacent side plates 32 and are adapted to move therewith. A center fan-shaped section 41 is stationary and fixed to the rear strut 26 of support frame 21 by suitable means, such as by welding. As shown in FIGS. 2, 3 and 4, finger guide elements 42 are provided on the back surface of stationary section 41 to support and guide the movable back wall sections 40 in the various positions thereof occasioned by the orientations of the side plates 22 which are caused by adjustments of the jack elements 28.
A plow or nose element 43, which is centrally positioned at the front or leading edge of the bucket 10, is mounted by bolts 44 to the hinge bar 27 to aid in keeping the bucket 10 on track during use.
FIGS. 3, 5 and 6 illustrate in detail the structure of the hinge 23 which generally comprises two interfitting leaf sections 45 and 46 having mounting flanges 47 and 48, respectively. The side plates may be affixed to the flanges 47 and 48 in any desired fashion, such as by welding or bolting as shown in FIG. 6. The leaf sections 45 and 46 are formed with interfitting barrel segments 49 and 50, respectively, which facilitate the insertion of the hinge pin 51 which holds the leaf sections together and allows the rotation of the leaf sections about the hinge axis. One or more of barrel segments 49 and 50 may be welded to the hinge bar 27 as shown in FIGS. 3 and 5.
The leading edge 55 of the bucket, as viewed in top plan view in FIGS. 1 and 6, is generally tapered outwardly and rearwardly into a spade-like configuration to facilitate digging into the ground during the use of the bucket. If desired, separate cutting blades with teeth may be fixed to this leading edge to protect the edge 55 from wear and to facilitate digging into the ground.
FIGS. 9 and 10 illustrate the front and rear views, respectively, of a modified bucket 60 which has a floor plate 61. The side plates 22 are hingedly connected along the outer edges of floor plate 61 by means of hinges 62 which are mounted to hinge bars 63. The support frame 64 of this particular embodiment has two depending components 65 which are similar to the single support frame 21 of the first described embodiment. Each of the depending components 65 is provided with a forward strut 66, a rear strut 67 and a hinge bar 63 to which the hinges 62 are connected. However, only one hanger base plate 68 is utilized and both forward struts 66 and rear struts 67 are welded or otherwise connected thereto. The yoke 12 and the upstanding ear 18 are fixed to the upper surface of the hanger base plate 68. The modified bucket 68 is pivotally connected to the rear of a dipper stick 11 and the operating rod 16 by means of the yoke 12 and ear 16 as described for the first embodiment. The back wall is sectioned, as shown, with the two fan-shaped outer sections 69 fixed to or formed integral with the ends of the adjacent side plates 22 and overlap the stationary, fan-shaped section 20 secured to the support frame 64. The outside sections 69 move with the side plates 22 when the orientation thereof is adjusted by jacks 28.
The bucket in accordance with the invention can be easily adjusted to form a trench having a wide variety of angled sides as shown in FIGS. 7 and 8 and 11 and 12. As indicated in FIG. 11, the trenches formed by the bucket of the invention need not be symmetrical around a vertical center line. The side plates 22 may be individually adjusted to provide the desired orientation for each wall of the trench formed. Other modifications to the invention can be made without departing from the scope thereof.
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This invention relates to an improved trenching bucket for use with trenching equipment such as backhoes, wherein the side plates of the bucket are adjustable so that trenches can be formed with walls at various slopes.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to the cell structure and fabrication process of power semiconductor devices. More particularly, this invention relates to a novel and improved cell structure and improved process for fabricating a trenched semiconductor power device with improved source metal contacts.
[0003] 2. Description of the Prior Art
[0004] Conventional technologies of forming aluminum metal contact to the N+ source and P-body in a semiconductor device is encountering a technical difficulty of poor metal coverage and unreliable electrical contact when the cell pitch is shrunken. The technical difficulty is especially pronounced when a metal oxide semiconductor field effect transistor (MOSFET) cell density is increased above 200 million cells per square inch (200M/in 2 ) with the cell pitch reduced to 1.8 um or to even a smaller dimension. The metal contact space to both N+ source and P-body for cell density higher than 200M/in 2 is less than 1.0 um, resulting in poor metal step coverage and high contact resistance to both N+ and P-body region. The device performance is adversely affected by these poor contacts and the product reliability is also degraded.
[0005] Referring to FIG. 1 for a standard conventional MOSFET cell 10 formed in a semiconductor substrate 15 with a drain region of a first conductivity type, e.g., an N+ substrate, formed at a bottom surface. The trenched MOSFET cell is formed on top of an epitaxial layer 20 of a first conductivity type, e.g., N− epi-layer that having a lower dopant concentration than the substrate. A body region 25 of a second conductivity type, e.g., a P-body region 120 , is formed in the epi-layer 20 and the body region 25 encompasses a source region 30 of the first conductivity type, e.g., N+ source region 30 . Each MOSFET cell further includes a N+ doped polysilicon gate 35 disposed in a trench insulated from the surrounding epi-layer 20 with a gate oxide layer 40 . The MOSFET cell is insulated from the top by an NSG and BPSG layer 45 - 1 and 45 - 2 with a source contact opening to allow a source contact metal layer 50 comprises titanium or Ti/TiN layer 50 to contact the source regions 30 . A single metal contact layer 60 overlaying on top to contact the N+ and P-well horizontally. The prior art MOSFET cell as shown in FIG. 1 encounters two fundamental issues due to the cell pitch shrinkage. One is the reduced contact area to both N+ source and P-body, resulting in high contact resistance. Another is poor metal step coverage due to high aspect ratio of contact height and open dimension.
[0006] In U.S. Pat. No. 6,638,826, Zeng et al. disclose a MOS power device as shown in FIG. 2 that includes V-groove trench contact to dispose single layer of metal to electrically contact the source vertically. The contact CD (Critical Dimension) can be shrunk significantly without increasing contact resistance, however, the formation of the V-groove contact is not easily controlled as result of wet chemical etch. Moreover, the contact CD is limited by an aluminum metal step coverage due to small contact.
[0007] Therefore, there is still a need in the art of the semiconductor device fabrication, particularly for trenched power MOSFET design and fabrication, to provide a novel transistor structure and fabrication process that would resolve these difficulties and design limitations.
SUMMARY OF THE PRESENT INVENTION
[0008] It is therefore an object of the present invention to provide new and improved processes to form a reliable source contact metal layer such that the above-discussed technical difficulties may be resolved.
[0009] Specifically, it is an object of the present invention to provide a new and improved cell configuration and fabrication process to form a source metal contact by opening a source-body contact trench by applying an oxide etch followed by a silicon etch. The source-body contact trench then filled with a metal plug to assure reliable source contact is established.
[0010] Another aspect of the present invention is to reduce the source and body resistance by forming a thin low-resistance layer with greater contact area to a top thick metal. The thin low-resistance layer forms a good contact to the source-body metal contact plug from the top opening of the source-body contact trench.
[0011] Another aspect of the present invention is to connect the front thick metal layer with either bonding wire or cooper plate to the electrodes of a lead-frame. The cooper plate connections provide reduced resistance and improved thermal dissipation performance.
[0012] Another aspect of the present invention is to further reduce the source and body resistance by applying a differential etch process to form the source-body contact trench with a wider top opening. A thin low-resistance layer is then formed on top of the MOSFET cell with wider opening area to contact the metal contact plug deposited into the source-body contact trench. The thin low resistance layer has a greater contact area to a top thick metal. The thin low-resistance layer further forms an improved contact to the source-body metal contact plug with wider contact area from the top opening of the source-body contact trench.
[0013] Briefly, in a preferred embodiment, the present invention discloses a trenched metal oxide semiconductor field effect transistor (MOSFET) cell that includes a trenched gate surrounded by a source region encompassed in a body region above a drain region disposed on a bottom surface of a substrate. The MOSFET cell further includes a source-body contact trench opened with sidewalls substantially perpendicular to a top surface into the source and body regions and filled with contact metal plug. In a preferred embodiment, the contact metal plug further comprising a Ti/TiN barrier layer surrounding a tungsten core as a source-body contact metal. In another preferred embodiment, the MOSFET cell further includes an insulation layer covering a top surface over the MOSFET cell wherein the source body contact trench is opened through the insulation layer. And, the MOSFET cell further includes a thin resistance-reduction conductive layer disposed on a top surface covering the insulation layer and contacting the contact metal plug whereby the resistance-reduction conductive layer having a greater area than a top surface of the contact metal plug for reducing a source-body resistance. In another preferred embodiment, the contact metal plug filled in the source body contact trench comprising a substantially cylindrical shaped plug. In another preferred embodiment, the MOSFET cell further includes a thick front metal layer disposed on top of the resistance-reduction layer for providing a contact layer for a wire or wireless bonding package. In an alternate preferred embodiment, the source-body contact trench having stepwise sidewalls and said contact metal plug filled in said source-body contact trench comprising a substantially cup shaped plug having a wider top contact area.
[0014] This invention further discloses a method for manufacturing a trenched metal oxide semiconductor field effect transistor (MOSFET) cell. The method includes a step of forming said MOSFET cell with a trenched gate surrounded by a source region encompassed in a body region above a drain region disposed on a bottom surface of a substrate. The method further includes a step of covering the MOSFET cell with an insulation layer and applying a contact mask for opening a source-body contact trench with sidewalls substantially perpendicular to a top surface of the insulation layer into the source and body regions. The method further includes a step of filling the source-body contact trench with contact metal plug. In a preferred embodiment, the step of covering the MSOFET cell with an insulation layer further comprising a step of depositing two different oxide layers on top of the MOSFET cell and applying a differential oxide etch to form a source-body contact trench having a step-wise sidewall with a wider top opening.
[0015] These and other objects and advantages of the present invention will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiment, which is illustrated in the various drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a side cross-sectional view of a conventional MOSFET device.
[0017] FIG. 2 is a cross sectional view of a trenched MOSFET device with V-Groove trench contact disclosed by a patented disclosure.
[0018] FIG. 3 is a cross sectional view of a MOSFET device of this invention with an improved source-plug contact.
[0019] FIG. 4 is a cross sectional view of another MOSFET device of this invention with an improved source-plug contact filled in a contact trench opening with stepwise sidewalls.
[0020] FIGS. 5A to 5 J are a serial of side cross sectional views for showing the processing steps for fabricating a semiconductor trench as shown in FIG. 3 .
[0021] FIG. 5F ′ is a side cross sectional view for illustrating a differential etch process to form a source-body contact trench with a step-wise sidewall for depositing a champagne-cup shaped source-body contact therein.
[0022] FIGS. 6A and 6B are top views of two kinds of bonding connections according two alternate embodiments of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] Please refer to FIG. 3 for a first preferred embodiment of this invention where a metal oxide semiconductor field effect transistor (MOSFET) device 100 is supported on a substrate 105 formed with an epitaxial layer 110 . The MOSFET device 100 includes a trenched gate 120 disposed in a trench with a gate insulation layer 115 formed over the walls of the trench. A body region 125 that is doped with a dopant of second conductivity type, e.g., P-type dopant, extends between the trenched gates 120 . The P-body regions 125 encompassing a source region 130 doped with the dopant of first conductivity, e.g., N+ dopant. The source regions 130 are formed near the top surface of the epitaxial layer surrounding the trenched gates 125 . The top surface of the semiconductor substrate extending over the top of the trenched gate, the P body regions 125 and the source regions 130 are covered with a NSG and a BPSG protective layers 135 and 140 respectively.
[0024] For the purpose of improving the source contact to the source regions 130 , a plurality of trenched source contact filled with a tungsten plug 145 surrounded by a barrier layer Ti/TiN 150 . The contact trenches are opened through the NSG and BPSG protective layers 135 and 140 to contact the source regions 130 and the P-body 125 . Then a conductive layer 155 is formed over the top surface to contact the trenched source contact 145 and 150 . A top contact layer 160 is then formed on top of the source contact layer 155 . The top contact layer 160 is formed with aluminum, aluminum-cooper, AlCuSi, or Ni/Ag, Al/NiAu, AlCu/NiAu or AlCuSi/NiAu as a wire-bonding layer. The conductive layer 155 sandwiched between the top wire-bonding layer 160 and the top of the trenched source-plug contact is formed to reduce the resistance by providing greater area of electrical contact.
[0025] FIG. 4 show another MOSFET device 100 ′ with similar device configuration as that shown in FIG. 3 . The MOSFET device 100 ′ also has a source contact plug 145 ′ composed of tungsten surrounded by conductive barrier layer Ti/TiN 150 ′. The only difference is the shape of the trench for disposing the source contact plug 145 ′ is formed with a stepwise sidewall thus the 145′ plug has a shape like that of champagne cup. The source-body contact trench with stepwise sidewall provides additional advantage. With a wider top opening, a broader contact area is provided and the contact resistance between the source-body contact plug and the top thick metal is further reduced.
[0026] Referring to FIGS. 5A to 5 J for a serial of side cross sectional views to illustrate the fabrication steps of a MOSFET device as that shown in FIG. 3 . In FIG. 5A , a photoresist 206 is applied to open a plurality of trenches 208 in an epitaxial layer 210 supported on a substrate 205 . In FIG. 5B , an oxidation process is performed to form an oxide layer 215 covering the trench walls. The trench is oxidized with a sacrificial oxide to remove the plasma damaged silicon layer during the process of opening the trench. Then a polysilicon layer 220 is deposited to fill the trench and covering the top surface and then doped with an N+ dopant. In FIG. 5C , the polysilicon layer 220 is etched back followed by a P-body implant with a P-type dopant. Then an elevated temperature is applied to diffuse the P-body 225 into the epitaxial layer 210 . In FIG. 5D , a source mask 228 is applied followed by an source implant with a N-type dopant. Then an elevated temperature is applied to diffusion the source regions 230 . In FIG. 5E , a non-doped oxide (NSG) layer 235 and a BPSG layer 240 are deposited on the top surface. In FIG. 5F , a contact mask 242 is applied to carry out a contact etch to open the contact opening 244 by applying an oxide etch through the BPSG and NSG layers followed by a silicon etch to open the contact openings 242 further deeper into the source regions 230 and the body regions 225 . The MOSFET device thus includes a source-body contact trench 244 that has an oxide trench formed by first applying an oxide-etch through the oxide layers, e.g., the BPSG and NSG layers. The source-body contact trench 244 further includes a silicon trench formed by applying a silicon-etch following the oxide-etch. The oxide etch and silicon etch may be a dry oxide and silicon etch whereby a critical dimension (CD) of the source-body contact trench is better controlled. In FIG. 5G , a Ti/TiN layer 245 is deposited onto the top layer followed by forming a tungsten layer 250 on the top surface that fill in the contact opening to function as a source and body contact plug. In FIG. 5H , a tungsten etch is carried out to etch back the tungsten layer 250 . In FIG. 5I , a Ti/TiN etch is carried out to etch back the Ti/TiN layer 245 . In FIG. 5J , a low resistance metal layer 255 is deposited over the top surface. The low resistance metal layer may be composed of Ti or Ti/TiN to assure good electric contact is established.
[0027] Referring further to FIG. 5F ′ for an additional differential etching process after the completion of the step shown in FIG. 5F . In FIG. 5F ′, a differential etch of NSG and BPSG is performed by using a dilute HF (10:1). A stepwise sidewall trench 244 ′ is formed because of the different etch rates between NSG layer 235 and BPSG layer 240 . The etch rate of NSG is 50 A/min if the dilute HF is 100:1 HF, and 300 A for BPSG. For the purpose of fabricating a MOSFET device as that shown in FIG. 4 with stepwise source-body contact trench with a champagne-cup shaped trench plug, the above-described processing steps as that shown in FIGS. 5G to 5 J are followed to complete the fabrication processes.
[0028] By further depositing a top contact layer 260 , as that shown in FIGS. 6A and 6B , over the low resistance metal layer 255 , e.g., a top contact layer 160 shown in FIG. 3 completes the manufacture of the device. The top metal 260 can be Al, AlCu or AlCuSi for wire-bonding such as Au wire or Al wire 270 as shown in FIG. 6A while Ni/Ag, Al/NiAu, or AlCu/NiAu or AlCuSi/NiAu top metal contact layer 260 ′ for wireless solder bonding using Cu Plate 275 as shown in FIG. 6B connected to a source electrode S for on-resistance reduction and improved thermal characteristics.
[0029] Although the present invention has been described in terms of the presently preferred embodiment, it is to be understood that such disclosure is not to be interpreted as limiting. Various alternations and modifications will no doubt become apparent to those skilled in the art after reading the above disclosure. Accordingly, it is intended that the appended claims be interpreted as covering all alternations and modifications as fall within the true spirit and scope of the invention.
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A trenched metal oxide semiconductor field effect transistor (MOSFET) cell that includes a trenched gate surrounded by a source region encompassed in a body region above a drain region disposed on a bottom surface of a substrate. The MOSFET cell further includes a source-body contact trench opened with sidewalls substantially perpendicular to a top surface into the source and body regions and filled with contact metal plug.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This patent application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/640,156, entitled “Coex Fascia Board Affixed to an Expansion Room to Provide a Decorative Frame, Gap Cover and Seal, at the Intersection of an Expansion Room and Body of a Recreational Vehicle,” filed Apr. 30, 2012, which application is incorporated in its entirety here by this reference.
TECHNICAL FIELD
[0002] This invention relates to boards for covering gaps between expansion rooms of a recreational vehicle and the wall of a recreational vehicle.
BACKGROUND
[0003] Current fascia boards for RV's are made of extruded powder coated aluminum which have an optional secondary seal within the extruded powder coated aluminum frame. The extruded powder coated aluminum frame is expensive to make and must be made in one piece, thereby increasing the cost of manufacture, assembly and affixation onto the wall of an expansion room of a recreational vehicle. An optional seal made out of cellular sponge material is also affixed to the extruded powder coated aluminum frame.
[0004] Because of the strength and durability of the aluminum fascia boards, no one has considered looking for alternatives. However, given the cost of making fascia boards out of aluminum, there is a need for alternatives.
SUMMARY OF THE INVENTION
[0005] A first preferred embodiment of the fascia board comprises a frame section made out of plastic, such as thermoplastic olefin (“TPO”), affixed to the expansion room at the location where the expansion room adjoins the recreational vehicle when the expansion room is in the retracted position into the recreational vehicle (“RV”). Each frame section may optionally include a bulb seal made out of a plastic material, such as, by way of example only, a flexible thermoplastic elastomer (“TPE”) or thermoplastic vulcanizate (“TPV”), coextruded with the frame section. In any of the embodiments, various components or subcomponents of the fascia board can be made of different or the same material, depending on the characteristics desired for each component, using a coextrusion, tri-extrusion, or in general, a multi-extrusion process. The frame sections of the fascia board may be mitered at their ends to provide an attractive form fit frame, gap cover and seal around the outer wall of the expansion room when the expansion room is retracted back into the RV and the outer wall of the expansion room is adjacent to the wall of the RV. In general, the fascia board provides a gap cover as well as a “seal” when the expansion room is in the closed position. Utilizing the plastic is a great cost saving alternative to aluminum
[0006] The fascia board comprises a frame section having an exterior wall and an interior wall. The first or upper end of the frame section may terminate in an optional arcuate section which functions as a cover. Spaced apart from the arcuate cover but adjacent to it may be a flexible bulb seal attached to or formed with the interior wall of the fascia board (e.g. by using a coextrusion, tri-extrusion, or, in general, a multi-extrusion process) and running the length of the frame section. Preferably, approximately two-thirds (⅔) of the width of the frame section closer to the lower end or second end, opposite the first end, is a transverse wall extending at approximately ninety (90) degrees to the frame section, the transverse wall having an upper surface and a lower surface, the transverse wall having a set of spaced apart openings. At a location immediately below the transverse wall but on the exterior wall of the frame section may be a first downwardly extending retention member extending for the length of the frame section. Parallel to it on the exterior wall and adjacent to the bottom end of the longitudinal section may be a second upwardly extending lower retention member extending for the length of the frame section. A set of spaced apart openings extend through the location of the frame section between the two retention members.
[0007] Preferably, the fascia boards are form fitted with three or four sections affixed to the expansion room to create an attractive gap cover and frame including the flexible bulb seal to also seal the gap area.
[0008] At the location of the expansion room, the RV has an opening into and out from which the expansion room slides to provide additional room space. The RV has an exterior wall. The expansion room has an exterior wall with an outer surface, a left sidewall, an upper wall and a right sidewall. By way of example only, the first fascia board is aligned so that the lower surface of the transverse wall rests on the upper wall of the expansion room. A set of fastening members are screwed through openings in the transverse wall and into the upper wall of the expansion room. The interior wall of the fascia board is aligned with the outer wall of the RV so that the bulb seal rests against the outer wall of the RV.
[0009] The lower portion of the interior wall of the fascia board rests against the outer surface of the expansion room and a set of fastening members may be screwed through openings of the fascia board and to the upper portion of the exterior surface of the expansion room. A secondary cover or panel may be retained between the retention members to conceal the fastening members.
[0010] In the same fashion, a second fascia board is aligned so that the lower surface of the transverse wall rests on a left sidewall of the expansion room. A set of fastening members may be screwed through openings in the transverse wall and into the left sidewall of the expansion room. The interior wall of the fascia board is aligned with the outer wall of the RV so that the bulb seal rests against the outer wall of the RV. The lower portion of the interior wall rests against the outer surface of the expansion room and a set of fastening members may be screwed through openings of the fascia board and to the left side portion of the exterior surface of expansion room. A secondary cover may be retained between the retention members to conceal the fastening members. The adjoining upper portions of two adjacent fascia boards are cut with a miter cut for a flush fit.
[0011] In the same fashion, a third fascia board is aligned so that the lower surface of the transverse wall rests on a right sidewall of the expansion room. A set of fastening members is screwed through openings in the transverse wall and into the right sidewall of the expansion room. The interior wall is aligned with the outer wall of the RV so that bulb seal rests against the outer wall of the RV.
[0012] The lower portion of the interior wall rests against the outer surface of the expansion room and a set of fastening members may be screwed through the openings of the fascia board and to the right side portion of the exterior surface of the expansion room. A secondary cover or panel is retained between the retention members to conceal the fastening members. The adjoining upper portions of two fascia boards are cut with a miter cut for a flush fit.
[0013] In some embodiments, a fourth fascia board may be aligned so that the lower surface of the transverse wall on the side of the second end rests on a bottom wall or floor of the expansion room. A set of fastening members is screwed through openings in the transverse wall and into the bottom wall of the expansion room. Portions of the interior wall of the fascia board may be aligned with the outer wall of the RV so that the bulb seal rests against the outer wall of the RV.
[0014] Another portion of the interior wall of the fascia board rests against the outer surface of the expansion room and a set of fastening members may be screwed through the openings of the fascia board and to the bottom portion of the exterior surface of the expansion room. A secondary cover or panel is retained between the retention members to conceal the fastening members. The adjoining portions of two fascia boards are cut with a miter cut for a flush fit.
[0015] Therefore, triplicate or quadruplicate fascia boards are affixed to the exterior surface of the expansion room. When the expansion room is retracted the fascia boards form a covering frame which is an attractive frame that also acts as a gap cover and sealing member to conceal the gap between the RV and the outer wall of the expansion room. By having three or four separate fascia boards made out of inexpensive TPO, the frame can be sized to perfectly fit the size of the outer wall of the expansion room.
[0016] In some embodiments of the fascia board, a set of fastening members are screwed through openings only in the transverse wall and into a sidewall of an expansion room. The interior wall of the fascia board is aligned with outer wall of RV so that bulb seal rests against outer wall of RV. The lower portion of interior wall rests against a portion of outer surface of expansion room. The fastening members on the exterior frame of the fascia board are eliminated and therefore a secondary cover or panel to conceal them is also eliminated. Three or four fascia boards are used for the frame in the same manner as the first embodiment.
[0017] A flat seal, which can be attached to or formed with the fascia board (e.g. by using a coextrusion, tri-extrusion, or, in general, a multi-extrusion process), or be a separate piece of waterproof acrylic foam tape on the underside of the transverse surface, provides more sealing power on the surface to which the transverse wall is affixed. An optional second bulb seal which is attached to or formed with the upper surface of the transverse wall (e.g. by using a coextrusion, tri-extrusion, or, in general, a multi-extrusion process) provides further sealing capability. The flat seal or waterproof tape and second bulb seals are optional and either both can be used or one or the other can be used.
[0018] Therefore, three or four fascia boards may be affixed to the exterior surface of the expansion room. When the expansion room is against the outer wall of the RV, they form a covering frame which is an attractive frame and also acts a gap cover and gap seal. By having three or four separate fascia boards made out of inexpensive TPO material, the frame can be sized to perfectly fit the size of the outer wall of the expansion room and this replaces an expensive extruded aluminum frame. By way of example, the seals are preferably made out of TPE or TPV.
[0019] In an alternative variation of the present invention, the structure is identical except that the two retention members are replaced with a snap hook and a post supporting a living hinge which supports a secondary cover or panel having a matching snap member which is retained onto the snap hook to act as a covering over the fasteners which affix the fascia board to the secondary cover or panel of the expansion room.
[0020] In an additional alternative embodiment, the fascia board has the fastening members, by which the fascia board is attached to the exterior wall, removed and the only fastening members are the fastening members through the transverse wall.
[0021] Further novel features and other objects of the present invention will become apparent from the following detailed description, discussion and the appended claims, taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1A shows four fascia boards of the present invention installed on a simplified representation of a RV.
[0023] FIG. 1B shows the RV with its expansion room pulled out, and the fascia boards removed.
[0024] FIG. 1C is a close-up of the cross-section of the RV shown in FIG. 1A taken along line 1 C- 1 C.
[0025] FIG. 1D is a close up of the area identified as 1 D in FIG. 1C .
[0026] FIG. 2A is a perspective view of the exterior side of an embodiment of the present invention.
[0027] FIG. 2B is a perspective view of the interior side of the embodiment shown in FIG. 2A .
[0028] FIG. 2C is a side view of the embodiment shown in FIG. 2A .
[0029] FIG. 3A is a perspective view of the exterior side of another embodiment of the present invention.
[0030] FIG. 3B is a perspective view of the interior side of the embodiment shown in FIG. 3A .
[0031] FIG. 3C is a side view of the embodiment shown in FIG. 3A .
[0032] FIG. 4A is a cross-sectional view of another embodiment of the present invention.
[0033] FIG. 4B is a side view of the embodiment shown in FIG. 4A .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] Although specific embodiments of the present invention will now be described with reference to the drawings, it should be understood that such embodiments are by way of example only and merely illustrative of but a small number of the many possible specific embodiments which can represent applications of the principles of the present invention. Various changes and modifications obvious to one skilled in the art to which the present invention pertains are deemed to be within the spirit, scope and contemplation of the present invention as further defined in the appended claims.
[0035] Note, the features in the drawings are not necessarily drawn to scale. Note also, the drawings are illustrative of the various features that can be combined in any variation or combination as described in the specification and not intended to limit any one embodiment to any specific combination of features.
[0036] Referring to FIGS. 1A-1D , the fascia board or cover 10 is designed to be installed or affixed to an expansion room 400 of an RV 300 at the location where the expansion room 300 adjoins the RV 300 when the expansion room 400 is in the retracted position into the RV 300 . This covers the gap 302 and creates a seal between the expansion room 400 and a wall of the RV 300 . As shown in FIG. 1A , sections of the fascia board 10 are mitered 118 , 218 to provide an attractive form fit.
[0037] Referring to FIGS. 2A through 2C , the first preferred embodiment of the present invention is a fascia board 10 made of plastic or filled plastic. By way of example only, the fascia board may be made of TPO or talc-filled TPO. The fascia board 10 comprises a frame section 12 having an exterior wall 14 and an interior wall 16 . The exterior wall 14 and interior wall 16 are bound by a first end 18 , a second end 30 opposite the first end 18 , a first side 19 adjacent to the first end 18 and the second end 30 , and a second side 31 opposite the first side 19 and adjacent to the first end 18 and the second end 30 .
[0038] In some embodiments, the first end 18 terminates in an arcuate section 17 which enhances the seal against the RV wall. The arcuate section 17 curves inwardly on the side of the interior wall 16 towards the RV wall. This inward curvature causes the arcuate section 17 to cover the contents in between the fascia board 10 and the RV, thereby creating an aesthetic appearance.
[0039] In some embodiments, on the interior wall 16 , preferably adjacent to the arcuate section 17 is an optional first seal 40 . Preferably, the first seal 40 is a flexible bulb seal 40 made of TPE (thermoplastic elastomer) or TPV (thermoplastic vulcanizate). The flexible bulb seal 40 may be attached to or formed with the interior wall 16 and may extend along the entire length L 1 of the frame section 12 , for example, by a coextrusion, tri-extrusion, or, in general, a multi-extrusion process.
[0040] In between the first end 18 and the second end 30 may be a transverse wall 20 . In the preferred embodiment, the transverse wall 20 is approximately two-thirds (⅔) of the distance from the first end 18 to the second end 30 , closer to the second end 30 . However, the transverse wall 20 can be anywhere along the interior wall 16 so long as when the transverse wall is inserted into the gap 302 between the expansion room 400 and the RV wall 310 , the portion of the frame section 12 in between the transverse wall 20 and the first end 18 sufficiently covers the gap 302 . The transverse wall 20 extends approximately perpendicularly from the interior wall 16 of the frame section 12 . The transverse wall 20 has a first surface 21 (or lower surface) and a second surface 23 (or upper surface) opposite the first surface 21 . In some embodiments, the transverse wall 20 may have a set of spaced apart openings 22 and 24 that go through the first and second surfaces 21 , 23 of the transverse wall 20 . Fasteners 22 A, 24 A can be used to secure the transverse wall 20 to the expansion room 400 . Other types of fastening mechanisms can be used to secure the fascia board 10 to the expansion room 400 that may not require pre-formed holes 22 , 24 . Preferably, the transverse wall 20 extends the full length L 1 of the frame section 12 .
[0041] In some embodiments, at a location immediately below the transverse wall 20 but on the exterior wall 14 of the frame section 12 is a first retention member 26 protruding outwardly and towards the second end 30 in a hook-like fashion. The first retention member 26 need not be immediately below the transverse wall 20 . In fact, the first retention member 26 can be positioned anywhere in between the first end 18 and a second retention member 28 described below. The first retention member 26 may extend the full length L 1 of the frame section from the first side 19 to the second side 31 .
[0042] Parallel to the first retention member 26 on the exterior wall 14 in between the second end 30 and the first retention member 26 is a second retention member 28 extending from the first side 19 to the second side 31 . Preferably, the second retention member 28 is adjacent to or extends out from the second end 30 . The second retention member 28 protrudes outwardly and towards the first retention member 26 in a hook-like fashion. Therefore, in the preferred embodiment, the first retention member 26 and the second retention member 28 , in conjunction with the portion of the exterior wall 14 therebetween, define a C-shaped channel 33 . In some embodiments, a set of spaced apart openings 32 and 34 extend through the exterior wall 14 and the interior wall 16 of the frame section 12 in between first retention member 26 and second retention member 28 . The retention members 26 , 28 are optional and some embodiments may not have retention members 26 , 28 . Fasteners 32 A, 34 A can be used to secure the frame section 12 to the expansion room 400 via the openings 32 , 34 . Other types of fasteners can be used as well that may not require pre-formed openings 32 , 34 .
[0043] In some embodiments, a second seal 42 , such as a bulb seal, may be attached to the second surface 23 of the transverse wall 20 . The second seal 42 is also optional. The second seal 42 may span across the entire length L 1 of the transverse wall 20 . In some embodiments, a third seal 43 may be attached to the first surface 21 of the transverse wall 20 . The third seal 43 may be a flat seal rather than a bulb seal. Like the second seal 42 , the third seal 43 may also span across the entire width of the transverse wall 20 . The second and third seals 42 , 43 may be flexible plastic material attached to or formed with the fascia board 10 , such as TPE or TPV. In some embodiments, the third seal 43 may be a waterproof acrylic foam tape on the first side 21 of transverse wall 20 that lends more sealing power on the surface to which the transverse wall 20 is affixed.
[0044] In use, by way of example only, four fascia boards 10 a, 10 b, 10 c, 10 d are form fitted with four sections affixed to the expansion room 400 to create an attractive fanciful frame. Since the components of the four fascia boards are essentially the same, the same reference numbers will be used in reference to the components. Referring to FIGS. 1A through 1D , at the gap 302 between the expansion room 400 and the RV wall 310 , there is an opening into which the expansion room 400 slides in and out to provide additional room space. The RV 300 has an exterior wall 310 . The expansion room 400 has an exterior wall 410 with an outer surface 420 having a left wall portion 430 , an upper wall portion 440 a right wall portion 450 , and a bottom wall portion 455 . The expansion room 400 also has an interior top wall 460 , a left sidewall 462 adjacent to the top wall 460 and the exterior wall 420 , and a right sidewall 466 opposite the left sidewall 462 and adjacent to the top wall 460 and the exterior wall 420 , and a bottom wall or floor 457 . The first fascia board 10 a is aligned so that the first surface 21 of transverse wall 20 rests on top wall 460 of the expansion room 400 . A set of fastening members 22 A and 24 A are screwed through openings 22 and 24 in transverse wall 20 and into top wall 460 of expansion room 400 . The portion of the interior wall 16 of the fascia board 10 above the transverse wall 20 is aligned with outer wall 310 of RV 300 so that the first bulb seal 40 rests against the outer wall 310 of RV 300 . The lower portion of interior wall 16 rests against the upper wall portion 440 of outer surface 420 of expansion room 400 and a set of fastening members 32 A and 34 A may be screwed through openings 32 and 34 of the fascia board 10 and to the upper portion 440 of the exterior surface 420 of expansion room 400 . A secondary cover or panel 29 may be retained between retention members 26 and 28 , if present, to conceal the fastening members 32 A and 34 A.
[0045] In the same fashion, a second fascia board 10 b is aligned so that first surface 121 of transverse wall 120 rests on the left sidewall 462 of the expansion room 400 . Fastening members 22 A, 24 A are screwed through openings 22 , 24 in the transverse wall 20 and into left sidewall 462 of expansion room 400 . The portion of the interior wall 16 above the transverse wall 20 (adjacent the first end 18 ) is aligned with outer wall 310 of RV 300 so that bulb seal 40 rests against the outer wall 310 of RV 300 . The lower portion of interior wall 16 (adjacent the second end 30 ) rests against the left portion 430 of outer surface 420 of expansion room 400 and a set of fastening members 32 A, 34 A are screwed through openings 32 and 34 of the fascia board 10 b and to the left side portion 430 of the exterior surface 420 of the exterior wall 410 of expansion room 400 . A secondary cover or panel 29 may be retained between retention members 26 and 28 to conceal the fastening members 32 A and 34 A. The adjoining upper portion of fascia boards 10 a and 10 b are cut with a miter cut 118 .
[0046] In the same fashion, a third fascia board 10 c is aligned so that first surface 21 of the transverse wall 20 rests on a right sidewall 466 of the expansion room 400 . A set of fastening members 22 A, 24 A are screwed through openings in transverse wall 20 and into right sidewall 466 of expansion room 400 . The portion of the interior wall 16 above the transverse wall 20 (adjacent to the first end 18 ) of the fascia board 10 c is aligned with outer wall 310 of RV 300 so that bulb seal 40 rests against outer wall 310 of RV 300 . The lower portion of interior wall 16 (adjacent the second end 30 ) rests against the right portion 450 of the outer surface 420 of expansion room 400 and a set of fastening members 32 A, 34 A are screwed through openings 32 , 34 of fascia board 10 c and to the right side portion 450 of the exterior surface 420 of expansion room 400 . A secondary cover or panel 29 is retained between retention members 26 and 28 to conceal the fastening members. The adjoining upper portions of the two fascia boards 10 a and 10 c are cut with a miter cut 210 .
[0047] In the same fashion, a fourth fascia board 10 d is aligned so that the first surface 21 of the transverse wall 20 rests on a bottom wall 457 of the expansion room 400 . A set of fastening members 22 A, 24 A may be screwed through openings in transverse wall 20 and into bottom wall 457 of expansion room 400 . In some embodiments, a portion of the interior wall 16 adjacent the first end 18 of the fascia board 10 d may be aligned with outer wall 310 of RV 300 so that bulb seal 40 rests against outer wall 310 of RV 300 . Another portion of interior wall 16 opposite the arcuate section 17 adjacent the second end 30 rests against the bottom wall portion 455 of the outer surface 420 of expansion room 400 and a set of fastening members 32 A, 34 A are screwed through openings 32 , 34 of fascia board 10 d and to the bottom wall portion 450 of the exterior surface 420 of expansion room 400 . A secondary cover or panel 29 may be retained between retention members 26 and 28 to conceal the fastening members. The adjoining lower portions of the two fascia boards 10 b and 10 d are cut with a miter cut 119 and adjoining lower portions of the two fascia boards 10 c and 10 d are cut with a miter cut 211 for a flush fit.
[0048] Therefore, in this example, four fascia boards 10 a, 10 b, 10 c, 10 d having substantially the same components, are affixed to the exterior 20 surface of the expansion room 400 . When the expansion room 400 is against the outer wall 310 of the recreational vehicle, they form a covering frame which is an attractive frame and also acts as a seal. By having four separate fascia boards made out of inexpensive TPO, the frame can be sized to perfectly fit the size of the outer wall of the expansion room. When properly affixed to the expansion room 400 , all fascia boards 10 a, 10 b, 10 c, 10 d (whether three or four are used) are bound within or coextensive with the borders or edges of the RV wall 310 . Therefore, in some embodiments, there may be a space between the border or edge of the RV wall 310 and a fascia board 10 a, 10 b, 10 c, or 10 d; or the fascia board 10 a, 10 b, 10 c, or 10 d may be flush or nearly flush with the border or edge of the RV wall 310 . By way of example only, when four fascia boards 10 a, 10 b, 10 c, 10 d are used, all four fascia boards 10 a, 10 b, 10 c, 10 d may be bound within the borders or edges of the RV wall 310 ; thereby creating a space in between the fascia boards 10 a, 10 b, 10 c, 10 d and the border or edge of the RV wall 310 . By way of another example, when three fascia boards 10 a, 10 b, 10 c are used, the side fascia boards 10 b, 10 c may extend flush or nearly flush with the bottom end of the RV wall 310 , while being well within the bounds of the sides and top of the RV wall 310 . Other arrangements and variations can be used depending on the type and style of the expansion room 400 so long as the fascia boards 10 a, 10 b, 10 c, 10 d provide an aesthetic frame to cover for the gap between an expansion room 400 and the RV wall 310 .
[0049] Referring to FIGS. 3A-3C , the details of an alternative embodiment of the fascia board 1010 are illustrated. In the preferred embodiment, the sections of the fascia board 1010 are made of plastic, such as rigid TPO material.
[0050] Essentially, the fascia board 1010 has the same components, characteristics, and features as the first fascia board embodiment 10 , with the exceptions noted below. Therefore, the fascia board 1010 comprises a frame section 1012 having an exterior wall 1014 and an interior wall 1016 . The exterior wall 1014 and interior wall 1016 are bound by a first end 1018 , a second end 1030 opposite the first end 1018 , a first side 1019 adjacent to the first end 1018 and the second end 1030 , and a second side 1031 opposite the first side 1019 and adjacent to the first end 1018 and the second end 1030 . In some embodiments, the first end 1018 terminates in an optional arcuate section 1017 , which functions as a seal against the RV wall 310 . Spaced apart from the arcuate section 1017 but adjacent to it is a flexible bulb seal 1040 made of a plastic material, such as TPE or TPV, attached to or formed with the interior wall 1016 and preferably extending the length “L 2 ” of the frame section 1012 . Preferably, at approximately two-thirds (⅔) of the width “W 2 ” of the frame section 1012 is a transverse wall 1020 having a first surface 1021 and a second surface 1023 , opposite the first surface extending at approximately ninety (90) degrees to the section 1012 . However, the transverse wall 1020 can be anywhere along the interior wall 1016 so long as when the transverse wall 1020 is inserted into the gap 302 between the expansion room 400 and the RV wall 310 , the portion of the frame section 1012 in between the transverse wall 1020 and the first end 1018 sufficiently covers the gap 302 . The transverse wall 1020 may have a set of spaced apart openings 1022 and 1024 .
[0051] At a location immediately below the transverse wall 1020 but on the exterior wall 1014 of the longitudinal section 1012 is a snap hook retention member 1026 that may extend for the length “L 2 ” of the frame section 1012 . The snap hook retention member 1026 comprises a first post 1050 that projects perpendicularly away from the exterior wall 1014 , then abruptly turns towards the first end 1018 of the frame section 1012 to create a lip 1052 . Parallel to the first post 1050 of the first snap hook retention member 1026 , on the exterior wall 1014 and adjacent the second end 1030 of the frame section 1012 is a second post 1025 extending perpendicularly away from the exterior wall 1014 and affixed to a living hinge 1027 . The living hinge 1027 is affixed to a secondary cover or panel 1029 , which, at the end opposite the living hinge 1027 , terminates in a retention member closing hook 1028 , all of which may extend for the length “L 2 ” of the frame section 1012 . A set of spaced apart openings 1032 and 1034 extend through the location of the frame section 1012 between snap hook retention member 1026 and the post 1025 . A secondary cover or panel 1029 , attached at one end to the living hinge 1027 , comprises a retention member closing hook 1028 which engages the snap hook retention member 1026 to cover the opening 1022 and 1024 . The secondary cover or panel 1029 can be bent at the living hinge 1027 (at approximately 90 degrees) so as to make the secondary cover or panel 1029 parallel to the exterior wall 1014 . This brings the retention member closing hook 1028 adjacent to the snap hook retention member 1026 so that the secondary cover or panel 1029 can be snapped on to the retention member closing hook 1028 . The fascia boards are form fitted with three or four sections affixed to the expansion room to create an attractive fanciful frame.
[0052] A flat seal 1043 made of plastic, such as TPE or TPV, may be attached to or formed with the fascia board 1010 on the first surface 1021 of the transverse wall 1020 , or a waterproof acrylic foam tape may be applied on the first surface 1021 of transverse wall 1020 to lend more sealing power on the surface to which the transverse wall 1020 is affixed. A second bulb seal 1042 made of plastic, such as TPE or TPV, may be attached to or formed with or affixed to the second surface 1023 of the transverse wall 1020 to provide further sealing capability.
[0053] In any of the aforementioned embodiments (but described here in reference to the first embodiment for ease of description only), the frame section 12 may further comprise a support 500 , as shown in FIGS. 4A and 4B . The support 500 may be integrated in between the interior wall 16 and the exterior wall 14 . In some embodiments, the support may extend the full length L 1 of the section 12 from the first end 18 to the second end 30 . In some embodiments, the support 500 may extend a partial length L 1 of the section 12 . Similarly, the support may extend the full width W 1 of the section 12 from the first side 19 to the second side 31 , or the support 500 may extend a partial width W 1 of the section 12 . The support 500 can be made of any type of rigid material, for example, plastic, wood, metal, carbon fiber, any composite, and any combination thereof. In the preferred embodiment, the support 500 is made of aluminum
[0054] In the preferred embodiment, the materials used may be various different types of plastic, filled plastic, or rubber, such as thermoplastic olefin, talc-filled thermoplastic olefin, thermoplastic elastomer, thermoplastic rubber, vulcanized rubber, and the like, or any combination thereof. The components and subcomponents may be created by a coextrusion, a tri-extrusion, or in general, a multi-extrusion process. By utilizing these multi-extrusion processes to make components and subcomponents of the same or different material, the manufacturer can fine tune the fascia board by utilizing the best type of material for the purpose intended for each component or subcomponent depending on the desired characteristics needed for those components or subcomponents, such as rigidity, flexibility, hardness, softness, and the like.
[0055] The foregoing description of the preferred embodiment of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention not be limited by this detailed description, but by the claims and the equivalents to the claims appended hereto.
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A cover affixed to an expansion room of a recreational vehicle (RV) to cover and seal a gap in between the expansion room and a wall of the RV. The cover has a transverse wall to attach to the expansion room. The cover may have one or two bulb seals, and/or a flat seal affixed to the cover and/or the transverse wall to improve the seal against the wall of the RV. An end abutting the wall of the RV may be curved towards the RV to further cover the gap. A secondary cover may be used to cover any exposed fasteners. A plurality of covers may be provided so that when the expansion room is against the wall of the RV, the plurality of covers form an attractive covering frame between the RV and the walls of the expansion room.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
[0002] Not Applicable
REFERENCE TO COMPUTER PROGRAM
[0003] Not Applicable
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] This invention relates to the design of reed valves.
[0006] 2. Background of the Invention
[0007] A reed valve consists of a reed 1 a ( FIG. 1 ), generally designed to be a long slender cantilever made from metal or plastic, flat and rectangular in shape. The fixed end 1 b of the flat face is attached to a stationary surface 1 c , whereas the opposite free end 1 d is free to deflect, primarily about the thinner cross-sectional axis 1 h of the reed. The free end of the reed covers a port 1 e also located also on a stationary surface, hereby referred to as a ported surface 1 f . The deflection is caused by fluid flowing perpendicular to the flat face of the reed's free end. Where fluid flows through the port upward and away from the ported surface, the flow encountering the reed deflects the reed away from the ported surface, providing an opening 1 g for continued free flow of fluid, and is referred to the permitted flow condition. Whereas, for fluid flowing reversely downwards towards the ported surface, and through the port, the reed is deflected towards the ported surface, causing contact with the ported surface, thereby covering the port, and blocking further flow of fluid. The reverse flow direction is referred to as the unpermitted flow direction. Therefore, fluid flow is permitted in one direction, and prevented in the opposite direction.
[0008] Reed valves function similarly to check valves, but are much lighter, and much more flexible. The lighter, more flexible reed requires less fluid force to deflect, and therefore provide distinct advantages over check valves. Because of these lower forces, reed valves actuate with lower differential pressures, flow rates, and for fluids with lower mass densities. Reed valves also provide advantages over check valves related to maintaining alignment of the reed free end relative to the port. While the reed is relatively free to bend about its minor axis 1 h , flexure is prevented laterally due to bending rigidity about its major axis 1 i . Additional alignment features such as sliding guides 2 a ( FIG. 2 ) required for check valves are not required, thereby eliminating additional friction or binding forces that can inhibit the motion of the check valve plunger 2 b . Less inhibited motion of the reed valve allows the reed valve to operate more consistently at lower pressures, flow rates, and fluid densities than check valves.
[0009] The major disadvantages of reed valves are, because of the lightness and flexibility, the reed must be long and slender. As such, the overall envelope of the reed valve is generally much larger than that of a check valve. For applications inline with piping systems, reeds require relatively large and complicated housings, and may be more susceptible to leakage, and may impractical in application due to the relatively large size. Additionally, reed valves do not contain higher pressures, due to the thin, slender section required for flexibility.
[0010] The proposed art is a compact reed 3 a ( FIG. 3 ) that is thin and flexible as the existing art, but is more compact in overall envelope, and therefore able to fit within the cross sectional envelope of adjoining piping. The compactness of the proposed art allows for larger porting and sealing surfaces within smaller housings, and therefore offers more opportunities for practical application. The proposed art achieves these advantages by utilizing maximum length arms 3 b which maximize the flexural length 3 c within the limitation of the port and respective piping diameter envelope. In addition to maximizing flexibility by maximizing length, the arm length extension creates an offset 3 m between the end of the arms and the center of the reed sealing surface 3 g . The offset 3 m permits further flexure of the arms and the reed sealing surface, thereby increasing the overall reed flexibility. The thickness 3 d of the thinner minor flexural axis further maximizes flexibility. The thickness may be the same as the remainder of the reed to simplify manufacturing of the reed by machining, cutting, or etching processes, or may be different to achieve other design goals.
[0011] The high flexibility of the arms also reduces stresses resulting from deflection of the reed arms. Such stresses, particularly at junctions 3 e from the arm to the fixed base 3 i and from the arm to the reed sealing surface 3 g , otherwise could be high. In applications where a high number of deflection cycles are anticipated, higher stresses could result in fatigue fracture of the reed arm. The stresses may be further reduced at the said junctions by utilizing compound radius transitions, also considered part of junctions 3 e . A large radius 5 a ( FIG. 5 ) widens the arm 3 b , distributing stresses over a wider surface. A smaller radius 5 b further transitions the arm geometry in the larger area of adjoining structure, controlling any stress concentrations. Both the flexible arms and the compound radii transitions minimize stresses, allowing for longer life in high cycle environments.
[0012] The arm thickness 3 d , width 3 f , and location near the reed sealing surface edge 3 h offers less restriction to flow than would other designs where the arms were thicker, wider, or placed farther away from the sealing surface edge 3 h . Smaller overall dimensions of the reed arms provide less drag area and more remaining area in the compact space for fluid to flow. Furthermore, the arms are placed close to the sealing edge to take advantage of direction of the flow streamlines exiting the plane of the sealing surface. Close to the reed sealing surface edge 3 h , the streamlines 4 a ( FIG. 4 ) run parallel to the reed sealing surface 3 g . As such, alignment of the width 3 f of arm 3 b with the flow streamlines 4 a is least restrictive to flow. Aligned with the flow streamline 4 a , the projected area of the arm on the flow is minimized, maintaining a larger remaining passageway for flow. Furthermore, the orientation of the arm width provides structural rigidity and strength of the valve to resist any inadvertent drag forces. Conversely, flow streamlines near port 4 d or close to the housing wall 4 e are oriented perpendicularly to the arm 3 b width. As such, less area would be available for free flow, drag forces on the arms would be higher due to the higher frontal area, and drag related bending about the arm 3 b weaker minor axis would produce higher stresses, and lower fatigue life.
[0013] To allow for a thin reed to resist high pressures under reverse flow conditions, a grated seat 3 j ( FIG. 3 ) is used in lieu of a single hole port. The grated seat supports the reed sealing surface span against pressure forces in the unpermitted flow direction. The grating contains a plurality of holes 3 k ( FIG. 3 ), which maximizes flow area in the permitted flow direction, while providing structural support via material remaining between holes 3 k , referred to as grating 3 l , to resist pressure forces in the unpermitted flow direction. Furthermore, the holes 3 k need not be equal in diameter or spacing. The size and spacing may be different in order to adjust the velocity and direction of the streamlines 4 a encountering the arms. For instance, the flow streamlines incident on the arms may be adjusted to be more parallel to the sealing surface 3 g by reducing the hole 3 k diameters on the outer perimeter of the hole pattern, and enlarging the hole 3 k at the center of the pattern. Enlarging the center hole would promote higher fluid velocity in the center of the port 4 d opening, whereas reducing the hole size at the outer perimeter would inhibit flow velocities at the port 4 d periphery. The velocity gradient would therefore bend the streamline 4 a more into alignment with the arm width 3 f.
[0014] A reed 3 a assembled with a grated reed seat 3 j defines a reed valve assembly.
[0015] The novelty of the proposed art is advantageous for liquid fluids as well as gas fluids. Operation in liquid applications provides for more sensitive actuation of the valve. The grated design allows exposure to higher pressure forces that typically are associated with liquid applications. The proposed art has fewer parts, as the spring, alignment mechanism, and sealing surface may be integrated into one part. As such, the more complicated multiple part check valve construction typically associated with fluidic service is replaced with a simpler, more reliable, and more cost effective integrated part.
OBJECTS AND ADVANTAGES
[0016] The objects and advantages of the proposed invention are:
a) A reed valve that is thin and flexible as the prior art, but is able to fit within the envelope of adjoining piping, allowing for smaller housings, b) Through the design of the flexural element junctions, able to minimize stresses related to deflection, thereby improving fatigue life, c) A simple design manufacturable by machining, cutting, or etching processes, d) The ability to consolidate multiple parts found in similarly compact check valves, such as springs, alignment features, and sealing surfaces, into one part, e) Small flexural element cross-sectional dimensions that offer low restriction to flow, and also by orientation of the flexural element cross-sectional minor and major dimensions within the flow streamline, maximizes remaining area available for fluid flow f) Orientation of the said minor and major dimensions to provide strength needed to structurally support the element from any inadvertent fluidic drag forces, g) Support of the sealing surface by a grated seat against the pressure forces in the unpermitted flow direction, and h) The size and location of specific passages in the grated seat to promote or inhibit fluid flow in specific locations in the port area, which affect the direction and velocity of resulting streamlines, particularly in the area of the flexible arms.
[0025] Further objects and advantages of the design will become apparent from a consideration of the drawings and ensuing description.
BRIEF SUMMARY OF THE INVENTION
[0026] The proposed invention combines the flexibility and lightness of current art reed valves with the compact size of current art check valves by utilizing maximum length arms, which act as the spring and alignment features for the sealing surface. The proposed art integrates these features, including the sealing surface, into one part, as do reed valves, but are difficult to achieve in compact check valve envelopes. The key features of the design, maximum length arms, provide both spring return and alignment of the sealing surface within a compact envelope. The cross-sectional dimensions of the arms are minimized to lower resistance to flow, but equally important, the arms are located near the sealing surface to orient the thin axis of the arm to be parallel to the flow streamline. Aligning the thin axis of the arms with the flow streamlines lowers the frontal drag area encountering the flow, thereby lowering flow resistance and related drag forces on the reed arm, and also maximizes the arm strong axis bending resistance to the inadvertent drag forces. A grated seat is also provided which supports the thin sealing surface of the reed from high pressures in the unpermitted flow direction, and by sizing and spacing the individual passages, further influences the orientation of the streamlines relative to the flexible arms.
DRAWINGS
Figures
[0027] FIG. 1 General Depiction of a Reed Valve (Prior Art)
[0028] FIG. 2 General Depiction of a Check Valve (Prior Art)
[0029] FIG. 3 Compact Reed and Grated Seat (Proposed Art), Exploded Assembly View
[0030] FIG. 4 Description of Flow Streamlines about the Compact Reed (Proposed Art), Sectional View
[0031] FIG. 5 Compound Radius Transition (Proposed Art), Detail Plan View
DRAWINGS
Reference Item Numerals
[0032]
[0000]
1a
Reed (Prior Art)
1b
Reed Fixed End (Prior Art)
1c
Stationary Surface (Prior Art)
1d
Reed Free End (Prior Art)
1e
Port (Prior Art)
1f
Ported Surface (Prior Art)
1g
Opening for Fluid Flow
1h
Reed Minor Axis
1i
Reed Major Axis
2a
Check Valve Sliding Guide
(Prior Art)
2b
Check Valve Plunger
3a
Compact Reed (Proposed Art)
(Prior Art)
3b
Maximum Length Arm
3c
Arm Flexural Length
(Proposed Art)
3d
Arm Minor Thickness
3e
Compound Radius Junction
(Proposed Art)
3f
Arm Width
3g
Reed Sealing Surface
3h
Reed Sealing Surface Edge
3i
Arm Fixed Base
3j
Grated Seat (Proposed Art)
3k
Grated Seat Hole (Proposed Art)
3l
Reed Seat Grating
3m
Offset of Arm Connection to
(Proposed Art)
Reed Sealing Surface
(Proposed Art)
4a
Flow Streamline
4d
Reed Port
4e
Reed Housing Internal Wall
4f
Close Proximity of
Maximum Length Arm to
Sealing Surface Edge
(Proposed Art)
5a
Large Radius of Compound
5b
Small Radius of Compound
Radius Junction (Proposed
Radius Junction (Proposed
Art)
Art)
DETAILED DESCRIPTION OF THE INVENTION
FIG. 3 —Preferred Embodiment
[0033] The preferred embodiment of the invention is the maximum length arms 3 b ( FIG. 3 ) of the compact reed 3 a . The arm is one or a symmetric pair, fixed at the base 3 i , spans approximately the entire width of the sealing surface 3 g along a trajectory approximately the same as the sealing surface edge 3 h , and terminates at the reed sealing surface 3 g so as to produce an offset 3 m from the said termination to the center of the sealing surface 3 g . The offset 3 m produces additional flexibility above that attained by the maximum length arms alone, by permitting additional flexure of the said surface 3 g and arm 3 b when urged by a fluid.
[0034] The importance of the maximum length arms to the flexibility can be explained by equation 1.
[0000]
1
k
∝
(
L
t
)
3
(
Equation
1
)
[0000] where,
1/k=Reed Flexibility L=Length of Arm t=Reed Thickness
[0038] The arm flexibility is increased cubically by lengthening the arm, as well as minimizing the thickness of the arm. In many applications, especially where the arm is integral with the reed sealing surface, reed pressure stresses prevent indiscriminate reduction in the thickness. Therefore, lengthening the arm becomes the predominant means to increasing flexibility. The maximum length arms allow for the increase in flexural length within the confines of a relatively small diameter of the adjoining piping.
[0039] Although the embodiment states that the reed arms follow a trajectory similar to the sealing surface edge 3 h , the arms may follow a different trajectory, but whose length is contained within the enclosing housing. The novelty of the invention is the ability of the reed arms to be long relative to the piping inside diameter, port diameter, and respective housing cavity to achieve an overall envelope approximately within the confines of the adjoining piping cross-section.
[0040] The arms are illustrated as pairs, being symmetric about a common axis. However, the arms may or may not be symmetric. Furthermore, the arm may be singular, not a pair, and may extend around any portion of the sealing surface to maximize length and flexibility. However, extending within one revolution around the cavity is a limitation of the embodiment, so as not to duplicate the prior art of coil springs. The embodiment emphasizes the primary mode of deflection to be by flexure, and not torsion.
[0041] The arms may be made from a variety of materials, depending on the application. Metallic materials such as steel, stainless steel, copper based alloys, or nickel based alloys may be used for applications demanding higher pressure and/or temperature. Non-metallic materials such as composites, polyethylene, polypropylene, or rubber may also be used in applications where pressure and/or temperature will not debilitate the material. The arms may be integral with the reed seat, and manufactured by cutting, machining, or chemical etching. The arms may also be separate from the reed seat, and joined mechanically, or by welding or bonding.
Additional Embodiments
FIGS. 3 , 4 , and 5
[0042] The compound radius transition 3 e ( FIG. 3 ) located at transitions from the arm 3 b to the fixed base 3 i and from the arm 3 b to the reed sealing surface 3 g is an additional embodiment. The compound radius transition 3 e contains a larger radius arc 5 a ( FIG. 5 ), and a smaller radius arc 5 b . The larger radius is approximately 2 times larger than the smaller radius, whose arcs are tangent to one another, and tangent to said adjacent transitions. The larger radius is located nearest the arm 3 b whereas the smaller radius is located nearest to the adjoining base 3 i or sealing surface 3 g.
[0043] Although compound radii generally consist of two radial arcs, tangent to each other, proportional by about 2:1, the compound radius transition may consist of more than two arcs of different radii, may or may not be tangent to one another or adjoining transitions, and may be proportional by other ratios than 2:1. Such features of the compound radii may be adjusted to produce the lowest possible stresses in areas of geometric transition, and stress concentration.
[0044] The close proximity 4 f ( FIG. 4 ) of the arm 3 b to the sealing surface edge 3 h is an additional embodiment. The close proximity 4 f aligns the width 3 f of the arm 3 b parallel to the flow streamlines 4 a . Near the sealing surface 3 g , the said streamlines are parallel to the sealing surface 3 g , and therefore are also parallel to the said aligned arm width, resulting in less obstruction to flow. While reorientation of the arm minor axis relative to the flow streamlines is possible in order to facilitate flow when locating the arms in other regions, the embodiment emphasizes that orientations of streamlines are less predictable farther away from boundary conditions. Furthermore, orientation of the arms out of plane with the remainder of the valve face is more costly to manufacture.
[0045] The grated seat 3 j ( FIG. 3 ) is an additional embodiment. The grated seat 3 j contains a plurality of holes 3 k contained within the sealing surface 3 g region which allow for minimal resistance to air flow in the permitted flow direction. Surrounding the holes is the remaining seat structure, either plastic or metallic, referred to as grating 3 l , which supports the reed sealing surface 3 g span from high pressures in the unpermitted flow direction. The reed sealing surface 3 g would otherwise encounter much higher stresses if the mid-span support was not present, as described in equation 2.
[0000]
σ
∝
p
×
(
a
t
)
2
(
Equation
2
)
[0000] where,
σ=Reed Sealing Surface Bending Stress due to Pressure p=Pressure a=Radius (½ Unsupported Span of Reed Sealing Surface) t=Reed Sealing Surface Thickness
[0050] For instance, grating whose hole span is one half the distance of the overall sealing surface would reduce the stress to one quarter of the stress without grating support.
[0051] The grating 3 l is further embodied to minimize the thickness of the maximum length arms 3 b in cases where the said arms are integral with the reed sealing surface. Minimizing the thickness maximizes arm flexibility, a preferred embodiment, and reduces arm flexural stresses.
[0052] The hole 3 k size and location are an additional embodiment. Each hole 3 k size and location in the sealing surface 3 g region influence the overall flow gradient across the port region, and therefore influence the direction of the flow streamlines 4 a ( FIG. 4 ). The hole 3 k diameter may or may not be circular, similar to each other in size, or whose location is equally spaced. The size, number, and spacing may be adjusted to accomplish any combination of structural support to the reed sealing surface 3 g , change in flow gradient, and subsequently, orientation of flow streamline 4 a for either flow performance or structural considerations.
Operation
Introduction to Prior Art
[0053] To understand the operation of the embodied invention, a discussion of the operation of the prior art may assist in the understanding of the more complex operation of the invention claimed. Fluid flowing through a port 1 e ( FIG. 1 ) in an upward direction impinges on the reed free end 1 d sealing surface. The reed 1 a is thin about the minor axis 1 h , long relative to the thickness, and therefore considered slender and flexible. Based on the slenderness, corresponding flexibility, and the fluid's impingement forces due to its pressure, density, and velocity, the sealing surface 1 d may deflect upward by some magnitude 1 g . The port is opened to flow, and fluid flow is permitted in the upward direction. Conversely, fluid flowing in the reverse direction will impinge downward upon the opposite face of the reed sealing surface, urging the reed upon the ported surface 1 f , thereby sealing the port and preventing fluid flow.
[0054] The reed and port may be in oriented differently, so as to directionally control flow in the desired direction.
[0055] Laterally, alignment of the reed free end 1 d relative to the port 1 e is maintained without supplemental alignment features such as guides. The major axis 1 i of the reed offers rigidity. Furthermore, the fluid impingement forces on the reed are not as significant due to the low projected frontal area in the lateral direction. As such, no additional alignment features are required, and related friction and binding are eliminated as problematic failure modes.
Operation
Preferred Embodiment (FIGS. 3 and 4 )
[0056] The proposed art compact reed functions similarly to the prior art, with a major advantage of smaller overall reed size for a similar corresponding port 4 d ( FIG. 4 ) size, thereby accommodating smaller housing cavities. Said slenderness and flexibility are attained by maximum length arms 3 b ( FIG. 3 ). The arms utilize to the maximum extent the available space and perimeter around the sealing surface 3 g , and the port covered by the said sealing surface, to achieve greatest possible length and flexibility, as illustrated in equation 1. An offset 3 m between the arm connection to the said sealing surface and the center of the said sealing surface further increases overall reed flexibility by permitting inclination of the said sealing surface, and also permitting flexure of the said sealing surface itself, when urged. Laterally, the arms provide rigidity as does the prior art for maintaining alignment of the sealing surface 3 g with the said port. The reed sealing surface 3 g functions identically in permitting and restricting flow as does the prior art.
Operation
Additional Embodiments (FIGS. 3 , 4 , and 5 )
[0057] The compound radius transition 3 e ( FIG. 3 ) mitigates high stresses that otherwise could be generated in prior art junctions. Where the flexural element, the arm 3 b , transitions in size to a fixed base 3 i or reed sealing surface 3 g , high stresses generally are encountered at the transition. To mitigate these stresses, single radii, thicker sections, or reinforcement may be added to reduce the stress levels. However, compound radii are simple and more effective in lowering concentrated stresses by gradually transitioning the flexural width 3 f . A larger radius 5 a ( FIG. 5 ) is used to gradually widen the section, and disperse the stresses, whereas, a smaller radius 5 b near the root of the transition may absorb the less intensive stresses. The ratio of the two said radii is generally 2:1, but may be different, and may include more than two radii.
[0058] Close proximity 4 f ( FIG. 4 ) of the arm 3 b to the sealing surface edge 3 h aligns the width 3 f of the arm 3 b in the streamline 4 a . Prior art generally limits reed deflection in the area of the sealing surface by way of a stationary surface, and does not generally encounter high flow rates in other unsupported flexural areas of the reed due to the large size, and remoteness from the port. The compact reed will incur higher flow rates around the arm 3 b where the arm is susceptible to unsupported flexure. Such flow in the arm regions may produce undesired drag, flow resistance, and arm stresses. To minimize drag related effects, the arm is located near the sealing surface edge 3 h to take advantage of streamlines 4 a aligned with the sealing surface 3 g flat boundary. Near the said edge, the flow streamline 4 a will be aligned with the surface 3 g , and therefore aligned with the adjacent arm 3 b width 3 f . Such alignment will reduce arm frontal area incident to the flow, and subsequent drag forces, and furthermore reduces bending stresses by orientation along the stronger axis of the arm section.
[0059] The grated reed seat 3 j ( FIG. 3 ) provides approximately the same flow area as a single hole port of the same overall envelope by employing a plurality of smaller holes 3 k contained within the region of the sealing surface 3 g . The holes are placed such that seat material remains between the holes, referred to as a grating 3 l . The grating supports the relatively thin reed, reducing the unsupported span, thereby reducing stresses due to pressure in the unpermitted flow condition, as demonstrated in equation 2. The holes 3 k need not be equal in size or spacing in order to adjust the nature of the flow impinging on the reed, and the direction and velocity of streamlines 4 a ( FIG. 4 ) encountering the arms. For instance, the flow streamlines 4 a incident on the arms 3 b may be adjusted to be more parallel to the sealing surface 3 g by reducing the hole 3 k ( FIG. 3 ) sizes on the outer perimeter of the hole pattern, and enlarging the hole 3 k at the center of the pattern. Enlarging the center hole would promote higher fluid velocity in the center, whereas reducing the hole size at the outer perimeter would inhibit flow velocities at the sealing surface 3 g periphery. The velocity gradient would therefore bend the streamline 4 a more before impinging upon the sealing surface 3 g , thereby adjusting the alignment of the streamline 4 a relative to the arm width 3 f.
CONCLUSION, RAMIFICATIONS, AND SCOPE
[0060] The proposed invention permits the use of reed valves in a wider range of applications. Such a design creates distinct and unique advantages:
a) A smaller, more compact, lighter reed valve assembly that may fit in smaller spaces, or in-line with smaller piping systems. b) A more robust reed which sustains higher fluid pressures, velocities, and densities. c) Although smaller and more robust, reed flexibility and lightness, and performance benefiting from said flexibility and lightness, which are maintained to that of prior art reed valves through the use of flexible arms which maximize their length within the confines of the smaller attainable housing. d) Furthermore, ability to maintain critical part alignment without additional alignment features in comparably small prior art check valves. e) Consolidation of multiple parts, such as sealing surfaces and return springs, into one part readily manufacturable by chemical etching, machining, or cutting. f) As such, broadening the range of applications for reed valves from prior art reed and check valves.
[0067] Although the description above contains much specificity, these should not be construed as limiting in scope of the invention, but merely providing illustrations of some of the presently preferred and additional embodiments of this invention. For example, the benefits of the proposed invention are not limited to housed assemblies attached to in-line piping systems, but may be more integral with fluidic circuits. The compact reed and grated reed seat may be installed in manifolds, internal to existing piping, or within the connection of two piping joints, threaded, welded, or brazed, without the use of a specially designed housing. The valve may be applied as a check valve, intake or exhaust valve for reciprocating pumps and gas compressors, or any other application requiring directional flow control. The fluids passing through the valve may be liquid or gas. The valve may be applied to medical applications as well as mechanical applications. The materials employed in the reed and reed seat may be metallic, plastic, wood, or composite. The sealing surface may not be in contact with the port when fluid is not impinging on or pressurizing the sealing surface. Fluid impingement or pressure may urge the sealing surface in contact with a ported surface, thereby preventing further flow in the fluid direction.
[0068] The flexible arms are illustrated as pairs, being symmetric about a common axis. However, the arms may or may not be symmetric. Furthermore, the arm may be singular, not plural, and may extend around any portion of the internal cavity to maximize length and flexibility. However, extending within one revolution around the cavity is a limitation of the embodiment, so as not to duplicate the prior art of coil springs. The offset between the end of the arms and the center of the sealing surface may or may not further incline the reed sealing surface so as to produce additional flexibility.
[0069] The reed valve assembly is defined as the compact reed assembled with a grated seat. However, the novelty applies also to a compact reed assembled with a prior art single hole port. The compact reed is advantageous without the added benefit of a grated reed seat.
[0070] To further distinguish the invention from prior art, the scope of the invention does not pertain to swing check valves, or directional control valves which utilize rotating hinges as a primary mechanism for movement of the sealing surface. The said hinges may or may not include springs which assist in returning the sealing surface to a predisposed position. Although the said sealing surface may displace in a similar trajectory to that of the proposed art, the proposed art is distinguished from the said hinge in that the proposed art displacement is by flexure of a single part, the flexible arm, and not by torsion of a single part such as a coil spring, and not via rotation of two separate parts connected by a pin, axle, or other rotary joint.
[0071] Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.
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Compact reeds maximize flexural length by efficiently utilizing available space surrounding the port. Maximum length arms are disposed at the perimeter of the housing inlet port. Stresses at the ends of the arms are mitigated by utilizing compound radius transitions. The transitions are constructed by two or more arcs of different radii, which produce lower stresses at such junctures than if single radius transitions were used. The arms are disposed close to the reed sealing surface edge to orient the flow streamlines to be aligned with the arm width, thereby minimizing frontal drag area. The reduced frontal area reduces drag forces and related stresses on the arms, and reduces the overall flow related pressure drop across the reed.
Replacing a single hole port, a port comprised of multiple passages of varying size control the velocity exiting the passages. The velocity gradient across the port provides further capability to orient the said streamlines to reduce said drag. In the reverse direction, where the reed obstructs flow, the ends of the passage walls provide structural support to the reed sealing surface, enabling the said surface to be thinner than otherwise possible.
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TECHNICAL HELD
The present invention relates to a method for installing a crack inducing expansion joint filler when placing concrete so as to reduce cracks generated during concrete construction, and an apparatus therefor and, more particularly, to a method for installing a concrete crack inducing expansion joint filler and an apparatus therefor which can vertically install and fix a plurality of fixed rod shafts on a bottom surface, place concrete, and then fit connecting means to the fixed rod shafts while connecting and installing a joint filler member, having a cover means (expansion joint filler marker) which can be attached and detached between the connecting means, before the concrete is cured. Thus, since it is possible to install the joint filler member at the same time as placing the concrete on the bottom surface, the method and apparatus can significantly reduce the concrete construction period and also cause that cracks generated by the joint filler during concrete curing can be reduced to a minimum, thereby increasing concrete durability and enhancing construction efficiency.
DISCUSSION OF RELATED ART
Generally, concrete is primarily used to pave the rooftop slave of apartment complexes or other various buildings, roads, ground, or underground parking lots, train station platforms, or subway roadbeds.
In the case of construction using concrete, which is a mix of cement, sand, gravel, and water, water evaporates from in the concrete while the concrete is cured, leaving gaps in the concrete. Such gaps repeatedly expand or contract due to heat in the air, causing cracks in the concrete.
Water may flow in the cracks, negatively affecting the building.
Thus, there is considered a method for constantly inducing cracks in the concrete in light that cracks are created in proportion to the area of installation of concrete in order to prevent or suppress such cracks.
For structural safety purposes by inducing cracks in the concrete, upon concrete construction, expansion joint fillers may be put at constant intervals or the concrete surface may be cut horizontally and vertically using a wet cutting machine or dry cutting machine.
Conventional expansion joint fillers absorb the expansion and contraction of concrete as the external air varies in temperature so that cracks by the expansion and contraction of concrete may be constantly induced along the expansion joint fillers, thus preventing durability of concrete from weakening due to water leakage by unpredicted cracks.
Such conventional expansion joint fillers are configured and installed in various forms.
Representative expansion joint fillers are disclosed in Korean Patent No. 10-0542380 titled “expansion joint filler structure for concrete slab and method for constructing the same” and Korean Patent No. 10-0385130 titled “expansion joint filler for concrete slab.”
The “expansion joint filler structure for concrete slab and method for constructing the same” disclosed in Korean Patent No. 10-0542380 is described below.
A concrete slab expansion joint filler structure for protecting a rooftop waterproof layer of a building includes thermal insulator expansion joint fillers 200 arranged in a grid on the waterproof layer 120 ; pressing concrete 130 poured and cured along with a wire mesh 132 on the thermal insulator expansion joint fillers 200 and the waterproof layer 120 ; a backup material 150 inserted into a cutting portion 220 obtained by cutting the pressing concrete 130 on the thermal insulator expansion joint fillers 200 after the pressing concrete 130 is cured; and a sealant 160 provided on the backup material 150 .
Further, the invention provides a method for constructing concrete slab expansion joint fillers for protecting a rooftop waterproof layer of a building, comprising the steps of (a) arranging thermal insulator expansion joint fillers 200 in a grid on the waterproof layer 120 ; (b) placing a wire mesh 132 on the thermal insulator expansion joint fillers 200 and the waterproof layer 120 ; (c) pouring and curing pressing concrete. 130 on the thermal insulator expansion joint fillers 200 and the waterproof layer 120 ; (d) cutting the pressing concrete 130 on the thermal insulator expansion joint fillers 200 after the pressing concrete 130 is cured to form a cutting portion 220 ; (e) inserting a backup material 150 into the cutting portion 220 ; and (f) putting a sealant 160 on the backup material 150 to finish off.
This is related to an expansion joint filler structure for concrete slab and construction method which installs thermal insulator expansion joint fillers on a waterproof layer, pours and cures pressing concrete, and then cuts a portion of the pressing concrete on the thermal insulator expansion joint fillers, and inserts a backup material and sealant into the cutting portion.
PRIOR TECHNICAL DOCUMENTS
Patent Documents
(Patent Document 1) KR 10-0385130 published on May 12, 2003.
(Patent Document 2) KR 10-0542380 published on Jan. 3, 2006.
(Patent Document 3) KR 20-0129425 published on Aug. 19, 1998.
SUMMARY
However, the conventional “expansion joint filler for concrete slab” has such structure that a connecting member is installed in a supporting member provided in a support, and a shock-absorbing part consisting of a supporting mechanism and a spring is provided in the connecting member to respond to the expansion and contraction of concrete, thereby preventing cracks in the concrete. Such structure is complicated and high in manufacturing costs, rendering itself uneconomical.
Further, since the conventional expansion joint filler is installed by the method of pouring concrete after the joint fillers are placed and fastened to the bottom surface, the joint fillers may be relocated or buried by pouring concrete.
Further, the conventional expansion joint filler should be installed on the bottom surface before pouring concrete, which requires more labor and costs, resulting in an increased construction time.
The present invention has been conceived to address the above issues.
An object is to provide a method for installing concrete crack inducing expansion joint fillers and expansion joint filler apparatus allowing an expansion joint filler apparatus including a plurality of fixed rod shafts installed and fixed at constant intervals on a bottom surface where concrete is placed, connecting means fitted and fastened to the fixed rod shafts, and an expansion joint filler member detachably installed between the connecting means to be configured to be installed before the concrete is cured, so that the expansion joint filler member may be installed simultaneously with placing the concrete on the bottom surface, thus significantly reducing the concrete construction period and allowing the expansion joint filler member to minimize cracks occurring when the concrete is cured, thereby leading to enhanced concrete durability and construction efficiency.
To achieve the above object, according to the present invention, an expansion joint filler apparatus installed on a bottom surface where concrete is placed to induce a crack comprises a plurality of fixed rod shafts each including a plate fixed to the bottom surface and a rod shaft vertically provided and fixed to an upper surface of the plate joint members each including a fitting installation pipe fitted and fastened to a corresponding one of the fixed rod shafts and multiple wing plates along a circumferential surface of the fitting installation pipe, and an expansion joint filler member fitted into the wing plates to connect and fasten the joint members.
According to the present invention, a method for installing an expansion joint filler apparatus installed on a bottom surface where concrete is placed to induce a crack comprises fixing a plate on the bottom surface by way of an adhering means while installing and fixedly arranging fixed rod shafts, placing the concrete on the bottom surface where the fixed rod shafts are arranged, fitting and fastening joint members to the fixed rod shafts when the concrete is in a mortar form before cured, and installing an expansion joint filler member between the joint members while pushing the expansion joint filler member so that a lower support of the expansion joint filler member is inserted into a space portion formed between a front plate and a rear plate of the joint members while the concrete is in the mortar form before cured.
According to the present invention, in the method for installing concrete crack inducing expansion joint fillers and apparatus therefor, the rod shafts are fastened at constant intervals to the bottom surface where the concrete is placed, and the concrete is then placed, and before the concrete is cured, the expansion joint filler member may be installed. Thus, the concrete construction period may be remarkably reduced, leading to low-cost construction and economy.
Further, according to the present invention, the connecting means are fitted over the rod shafts fixedly installed to the bottom surface, and the expansion joint filler member may be fittingly installed to the connecting means, allowing for simplified installation of the expansion joint filler member.
Further, according to the present invention, the expansion joint filler member is hollow to absorb the expansion and contraction of concrete, preventing the concrete from cracking while allowing for simple, low-price manufacture.
Further, according to the present invention, the connecting means for connecting and installing the expansion joint filler member may be formed in various shapes, such as a rectangular, triangular, or T shape, allowing for quick response to the environment of the bottom surface where the expansion joint filler member is constructed. Further, a color may be applied to the upper surface of the expansion joint filler member, allowing the bottom surface various decorations.
Further, according to the present invention, the upper portion of the expansion joint filler member is configured as a detachable expansion joint filler cover (marker). Thus, the expansion joint filler cover may be removed as necessary, and a sealing means, such as silicone, may be applied, providing for significantly enhanced sealing efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 and 2 are perspective views illustrating a concrete crack inducing expansion joint filler apparatus according to the present invention;
FIG. 3 is an exploded perspective view schematically illustrating a concrete crack inducing expansion joint filler apparatus according to the present invention;
FIG. 4 is a cross-sectional view illustrating an example in which concrete is poured with a concrete crack inducing expansion joint filler apparatus installed, according to the present invention;
FIG. 5 is a view schematically illustrating a main part of a concrete crack inducing expansion joint filler apparatus according to the present invention; and
FIG. 6 is a view schematically illustrating various examples of a connecting means of a concrete crack inducing expansion joint filler apparatus according to the present invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Hereinafter, preferred embodiments of the present invention are described with reference to the accompanying drawings to be easily practiced by one of ordinary skill in the art.
According to the present invention, as shown in FIGS. 1 to 5 , a concrete crack inducing expansion joint filler apparatus 100 includes a plurality of fixed rod shafts 110 fixed and installed at predetermined intervals on a bottom surface where concrete is poured and placed, joint members 120 including fitting installation pipes 121 fitted and fastened to the fixed rod shafts 110 and multiple wing plates 122 provided along circumferential surfaces of the fitting installation pipes 121 , and expansion joint filler members 130 fitted into the wing plates 122 of the joint members 120 and connecting and fastening the joint members 120 .
In such construction that concrete is poured on a broad bottom surface, such as an underground or above-ground parking lot or rooftop to securely maintain the bottom surface, water evaporates as the concrete is cured, causing cracks to irregularly occur in the cured concrete bottom surface. To prevent this, concrete is poured, with expansion joint fillers installed to induce cracks during concrete construction.
Accordingly, the concrete crack inducing expansion joint filler apparatus 100 according to the present invention is installed on the bottom surface to prevent cracks from occurring upon concrete construction.
Here, the fixed rod shafts 110 each include a plate 111 fixed to the bottom surface and a rod shaft 112 vertically installed and fixed to the top of the plate 111 .
Thus, the plate 111 is fixedly installed on the bottom surface of the constructed building using an adhering means, such as mortar or a glue or adhesive.
Then, the rod shaft 112 provided on the top of the plate 111 may be installed and fastened perpendicular to the bottom surface.
The rod shaft 112 may be formed in a multi-part, telescopic antenna structure that may expand or contract so that its length is adjustable.
Accordingly, the rod shaft 112 may be rendered to expand or contract in length depending on the thickness of concrete placed on the bottom surface of the building.
The wing plates 122 of the joint member 120 include a pair of front plate 122 a and rear plate 122 b and a space portion 122 c spacing the front plate 122 a and the rear plate 122 b apart from each other. A side surface portion of the wing plates 122 is connected to the fitting installation pipe 121 to be closed, and the other side surface portion thereof is open.
A plurality of wing plates 122 are provided along the circumferential surface of the fitting installation pipe 121 , and the angle between the wing plates 122 may be 90 degrees so that the joint member 120 is shaped as a rectangle, or the angle between the wing plates 122 may be 120 degrees so that the joint member 120 is shaped as a triangle.
As such, the joint member 120 may have various shapes, such as a rectangular shape, triangular shape, T shape, Y shape, or L shape, by adjusting the number and angle of the wing plates 122 .
The expansion joint filler member 130 may be formed of an elastic material, such as PVC. The expansion joint filler member 130 includes a hollow lower support 131 having both ends each of which may be inserted into the space portion 122 c between the front plate 122 a and the rear plate 122 b , an inverted trapezoidal, hollow upper head 132 formed to continuously communicate with an upper end of the lower support 131 to prevent the lower support 131 from sliding down along the space portion 122 c , and an inverted trapezoidal expansion joint filler marker 133 detachably fitted into the upper head 132 .
Protrusions 132 a projecting upwards and having ends bent inwards are formed at two opposite side edges of an upper portion of the upper head 132 , and an upper surface of the upper head 132 forms grooves 132 b by the protrusions 132 a.
Fitting grooves 133 a are formed in side edges of a lower portion of the expansion joint filler marker 133 to allow the protrusions 132 a to be fitted and supported.
Thus, as the protrusions 132 a are fitted along the fitting grooves 133 a , the expansion joint filler marker 133 may be positioned and fastened to the upper head 132 .
Further, in the expansion joint filler member 130 according to the present invention, as the expansion joint filler marker 133 is pulled upwards from a side surface, with the expansion joint filler marker 133 is fitted to the upper head 132 , the protrusions 132 a may be elastically deformed to be escaped from the fitting grooves 133 a . Thus, the expansion joint filler marker 133 may be easily attached or detached from the upper head 132 .
In case a gap occurs between the side surface of the embodiment marker 133 and the concrete due to the contraction of the concrete when the concrete is cured, the expansion joint filler marker 133 may be replaced with another expansion joint filler marker as large as the size of the gap to fill the gap, or a sealing means may be applied to the grooves 132 b formed on the upper surface of the upper head 132 , with the expansion joint filler marker 133 removed, thereby preventing the influx of, e.g., moisture.
Further, wing protrusions 131 a are formed on both side portions of the lower support 131 constituting the expansion joint filler member 130 to prevent the concrete from pushing up the expansion joint filler member 130 as the concrete contracts when it is placed in the concrete.
Further, the lower end of the lower support 131 of the expansion joint filler member 130 is formed as an inserting portion 131 b with a cone-shaped sharp tip allowing it to be easily placed in the concrete before the concrete is cured.
A method for installing the concrete crack inducing expansion joint filler apparatus 100 configured as above, according to the present invention, is described below.
First, multiple fixed rod shafts 110 are arranged and fastened to the bottom surface where concrete is to be poured at constant intervals using an adhering means, such as mortar or adhesive (the step of adhering and fastening the fixed rod shafts 110 to the bottom surface).
At this time, since the plates 111 have a large area, it may be easily attached to the bottom surface by way of the adhering means. Further, the rod shaft 112 is installed to expand or contract fitting the thickness of the thickness of the concrete placed.
In this case, the position where the fixed rod shafts 110 are to be fixed is previously designed and marked.
Subsequently, concrete is poured and placed on the bottom surface (the step of placing concrete).
At this time, as the fixed rod shafts 110 are soaked in the concrete, only the rod shafts 112 are shown. Here, the fixed rod shafts 110 may be adjusted to expand fitting the thickness of the placed concrete.
The joint members 120 are fitted and installed to the rod shafts 112 when the concrete remains mortar before cured (the step of fitting and fixing the joint members 120 to the fixed rod shafts 110 in the concrete of the mortar form).
At this time, since the concrete is placed on the bottom surface, only the rod shafts 112 are shown, but the plates 111 are not. Thus, the joint members 120 may be simply installed to the fixed rod shafts 110 by fitting the fitting installation pipes 121 over the rod shafts 112 .
Then, when the concrete remains in the form of mortar before cured, the expansion joint is filler member 130 is pressed down between the joint members 120 so that the lower support 131 is fitted into the space portion 122 c between the front plate 122 a and the rear plate 122 b (the step of coupling the expansion joint filler member 130 between the joint member 120 and its neighboring joint member 120 in the concrete of mortar form).
Here, the lower support 131 may be easily installed because the inserting portion 131 b formed at the lower tip of the lower support 131 is pressed down into the mortar-form concrete.
In such case, even when the concrete contracts while cured, the expansion joint filler member 130 is prevented from being pushed up by the wing protrusions 131 a formed on both side surfaces of the lower support 131 .
Further, at this time, the expansion joint filler member 130 is pushed down while tapped, so that the upper surface of the expansion joint filler marker 133 is on the same level as the concrete surface.
As the concrete is cured, the bottom surface construction is complete (the step of curing concrete).
The concrete contracts as cured on the bottom surface. At this time, even when the expansion joint filler member 130 is pressurized by the contracting concrete, cracks may be prevented from occurring or induced because the expansion joint filler member 130 is formed of an elastic material and includes a space absorbing the contracting force of the concrete.
Further, as the concrete contracts, gaps may occur in the outer surface of the expansion joint filler marker 133 of the expansion joint filler member 130 . In this case, the expansion joint filler marker 133 may be pulled up, removed, and replaced with a larger expansion joint liner marker to remove (fill) the gaps.
By doing so, the gaps created by the expansion joint filler member 130 may be filled, preventing influx of moisture into the inside of the concrete.
Further, as necessary, the expansion joint filler marker 133 may be pulled up and removed, and a sealing member, such as silicone, may be applied for sealing to the grooves 132 b formed on the upper surface of the upper head 132 .
Further, according to the present invention, various colors or shapes may be applied to the expansion joint filler marker 133 to show a diversity of colors or shapes, decorating the bottom surface.
As described above, according to the method for installing concrete crack inducing expansion joint fillers and expansion joint filler apparatus allowing an expansion joint filler apparatus including a plurality of fixed rod shafts installed and fixed at constant intervals on a bottom surface where concrete is placed, connecting means fitted and fastened to the fixed rod shafts, and an expansion joint filler member detachably installed between the connecting means to be configured to be installed before the concrete is cured, so that the expansion joint filler member may be installed simultaneously with placing the concrete on the bottom surface, thus significantly reducing the concrete construction period and allowing the expansion joint filler member to minimize cracks occurring when the concrete is cured, thereby leading to enhanced concrete durability and construction efficiency.
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The present invention relates to a method for installing a crack inducing expansion joint filler when placing concrete so as to reduce cracks generated during concrete construction, and an apparatus therefor and, more particularly, to a method for installing a concrete crack inducing expansion joint filler and an apparatus therefor which can vertically install and fix a plurality of fixed rod shafts on a bottom surface, place concrete, and then fit connection means to the fixed rod shafts while connecting and installing a joint filler member, having a cover means which can be attached and detached between the connection means, before the concrete is cured. Thus, since it is possible to install the joint filler member at the same time as placing the concrete on the bottom surface the method and apparatus can significantly reduce the concrete construction period and also cause that cracks generated by the joint filler during concrete curing can be reduced to a minimum, thereby increasing concrete durability and enhancing construction efficiency.
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CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of application Ser. No. 08/663,155 filed Jul. 26, 1995, now U.S. Pat. No. 5,839,517 which was a continuation-in-part application of Ser. No. 08/009,695 filed on Jan. 27, 1993, now abandoned.
FIELD OF THE INVENTION
This invention relates to the area of vibration isolators. Specifically, the invention relates to the area of elastomer-containing vibration isolators for isolation of a user from mechanical vibrations of hand-held vibrating devices.
BACKGROUND OF THE INVENTION
One of the problems facing users of hand-held vibrating equipment is exposure to elevated mechanical vibration levels. Long term exposure has produced symptoms of vascular, nervous system and bone/muscle deterioration such as hand-arm vibration syndrome and white hand. Many have attempted to solve the problem of excessive vibration transmitted to the users of hand-held tools by incorporating elastomer elements between the user and the vibrating device. Approaches have attempted to isolate and/or damp the mechanical vibration of the device.
One such isolating approach is taught in U.S. Pat. No. 3,968,843 to Shotwell, which is hereby incorporated by reference, and provides a pneumatic air hammer with a shock and vibration-absorbing insert or cushion member 30 between the body of the tool 10 and the handle 19. The isolator used is a plain compression-type sandwich isolator. Its theory of operation is to place a soft spring between the user and the vibrating device, thus isolating the user from mechanical vibration. However, compression-type isolators have one serious drawback. They experience an inherent stiffening effect when the operator exerts an increased force on the tool. This is due to the inherent strain sensitivity of elastomer in compression. Because of this, as the force increases, the level of vibration felt by the user is worsened. In other words, the harder the operator pushes the more ineffective the isolator becomes.
In addition, in order to maintain control of the tool, the cocking and torsional motions of the tool must be restrained. U.S. Pat. No. 2,500,036 to Horvath uses dual resilient members 80 and 81 to allow limited axial movement and restrain cocking. It also uses a plurality of locking segments 85 to restrain torsional rotation of the handle member 13 relative to the barrel 10.
In U.S. Pat. No. 5,054,562 to Honsa et al., an isolator which was to provide axial vibration isolation as well as cocking/torsional control by surrounding the working cup 20 with laminar layers of elastomer is described. Although this makes for a convenient package, this has the same inherent problem of compression strain stiffening as the Shotwell '843 approach.
As taught in U.S. Pat. No. 4,401,167 to Sekizawa et al., others have attempted to place the elastomer elements 6a and 6b between the tool body 1 and the handle 2. Although placing the elastomer in shear substantially eliminates the strain stiffening effects, it cannot provide low enough stiffness for optimum control and still maintain control of the tool.
Further attempts to improve the vibration isolation characteristics of hand-held tools have included the addition of fluid damping to the isolator. By adding damping, over and above what is available from an elastomeric device alone, the vibrations emanating from the tool can be further reduced. U.S. Pat. No. 4,667,749 to Keller, which is hereby incorporated by reference, describes such an isolator which adds fluid damping to an isolator and which is suitable for mounting a handle to a vibrating tool body.
Further, U.S. Pat. No. 4,236,607 to Hawles et al. describes a vibration suppression system wherein the fluid passes through the inner member of the mounting to provide amplified counter inertial forces. The commonly assigned U.S. Pat. No. 4,969,632 issued to Hodgson et al. and U.S. Pat. No. 4,733,758 issued to Duclos et al., which are both hereby incorporated by reference, describe other tunable mountings.
SUMMARY OF THE INVENTION
The present invention has been designed to provide an improved vibration isolator for reducing the mechanical vibration level transmitted to the user in order to overcome the features and shortcomings of the available mountings for vibrating hand-held devices and tools.
According to the invention, a isolator for use in a vibrating hand-held device is provided with a spring rate characteristic which preferably softens as the operator increases the force applied to the device thereby improving the vibration isolation and solving the stiffening effect inherent in the isolators used in prior art hand-held vibrating devices.
Further, the invention provides an isolator for use in a hand-held vibrating device which exhibits a spring rate characteristic for the mounting which softens by about a factor of 2 or more, and more preferably, about softens by about a factor in the range of 2 to 2, with increased application of force by the operator thus improving the vibration isolation.
The present invention also provides an elastomeric isolator for a hand-held vibrating device which uses a buckling section incorporated into the isolator within the hand-held vibrating device.
Also, the present invention also provides a buckling section isolator for incorporation into the vibrating device which comprises a means for allowing axial vibration isolation of the tool body relative to the tool handle and means incorporated therein for restraining torsional rotational and cocking of the tool body relative to the tool handle essential for control of the vibrating device.
According to another aspect, the present invention also provides a buckling elastomer isolator for incorporation into the vibrating device which includes a means for snubbing to prevent unwanted excess motions.
In another aspect, the invention includes an elastomeric grip isolator for use on a vibrating device which is a means for providing radial vibration isolation to the user by incorporating multiple radial buckling elements into the grip isolator.
The present invention further includes an elastomeric and fluid isolator for use on a vibrating hand-held device which comprises a means for providing vibration isolation of the user at a discreet operating frequency by incorporating inertial fluid forces within the elastomeric and fluid isolator, for example.
In another aspect, the invention includes an elastomeric and tuned mass isolator for use on a vibrating hand-held device which is a means for providing vibration isolation of the user at a discreet operating frequency by incorporating inertial forces within the vibrating device.
Moreover, the invention further includes a buckling isolator for use on a vibrating hand-held device wherein said buckling isolator includes metal buckling elements for providing vibration isolation of the user.
In a more detailed aspect of present invention is provided an elastomeric and fluid isolator for use on a vibrating hand-held device which includes a means for providing vibration isolation of the user at a discreet operating frequency by incorporating inertial fluid forces within the elastomeric and fluid isolator and which utilizes a buckling section within the isolator.
In summary, it is a feature of the instant invention to provide the above mentioned objects by providing a vibration isolator for use on a hand-held vibrating device for reducing the mechanical vibration imparted to the user, comprising a handle for being grasped by said user; a tool body; and a vibration isolator attached between the handle and the tool body, said vibration isolator including a buckling section which buckles under application of load, thus reducing the spring rate within an operating range and reducing said mechanical vibration imparted to said user within said operating range.
According to another feature, the invention is a hand-held vibrating device for reducing the mechanical vibration imparted to the user, comprising: a tool handle graspable by a user, a tool body moveable relative to said tool handle, said tool body adapted to receive a tool, a vibration isolator attached between said tool handle and said tool body, said isolator including: first end member attached to said handle, said first member including a first radially extending flange including a first axial face, a second end member attached to said tool body, said second end member including an axially directed section extending towards said first axial face of said first end member and including an external peripheral surface; and an elastomeric element bonded between said first axial face of said radially extending flange and said external peripheral surface.
It is an additional feature to provide an elastomeric vibration isolator for use on a hand-held vibrating device which reduces the radial mechanical vibration imparted to the user, comprising a body of elastomer for being grasped by said users hand, said body of elastomer disposed about a central axis; multiple buckling sections extending radially inward toward said central axis, said buckling sections buckling under application of load and reducing the spring rate which improves radial vibration isolation.
It is another feature of the instant invention to provide a hand-held vibrating device which reduces the mechanical vibration imparted to the user, comprising: a handle for being grasped by said user; a tool body; a tool bit attached to said tool body; a buckling isolator attached between said handle and said tool body, said buckling isolator including a buckling section which buckles under application of load along an axial axis, thus reducing the spring rate and improving the axial vibration isolation; a grip isolator further including a body of elastomer for being grasped by the users hand, said body of elastomer disposed about a central axis and surrounding one selected from the group consisting of said tool bit and said tool body, multiple buckling sections extending radially inward toward said central axis, said multiple buckling sections buckling under application of load and reducing the spring rate and improving the radial vibration isolation.
It is also a feature of the instant invention to provide a hand-held vibration device including a fluid and elastomer vibration isolator for use between a handle and a tool body, comprising: a first variable volume chamber; a second variable volume chamber; a first flexible element defining at least a portion of said first variable volume chamber; a second flexible element defining at least a portion of said second variable volume chamber; a fluid passageway between said first and second variable volume chambers; a fluid contained within, and substantially filling, said first variable volume chamber, said second variable volume chamber, and said fluid passageway; whereby vibrations of said tool body cause said fluid to flow within said fluid passageway between said first variable volume fluid chamber and said second variable volume fluid chamber and create forces which reduce the vibration transmitted to said handle.
It is an advantage of the present invention that the lower stiffness, as compared to conventional isolators at the optimum operating load, reduces the vibrating forces transmitted to the user.
It is an advantage of the present invention that the buckling element incorporated into the isolators can reduce the vibration experienced by the user.
It is a further advantage of the present invention that the axial isolation can be dramatically increased without reducing the control of the vibrating device by restraining both cocking motion and torsional motion of the tool handle relative to the tool body.
It is a further advantage of the present invention that the axial isolation can be dramatically increased by tuning an amplified fluid inertial force to coincide with the operating frequency.
The above mentioned and further features, advantages and characteristics of the present invention will become apparent from the accompanying descriptions of the preferred embodiment and attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings which form a part of the specification, illustrate several embodiments of the present invention. The drawings and description together, serve to fully explain the invention. In the drawings,
FIG. 1A is a partially sectioned side view showing the installation of an embodiment of the buckling isolator and an embodiment of the grip isolator on a hand-held vibrating device;
FIG. 1B is a partially sectioned side view showing a second embodiment of the grip isolator;
FIG. 2A is a sectioned side view illustrating an embodiment of a grip isolator for a hand-held vibrating device as seen along line 2A--2A in FIG. 2B;
FIG. 2B is an end view illustrating an embodiment of the grip isolator and illustrating the multiple buckling sections;
FIG. 2C is an enlarged partial isometric view illustrating one of the buckling sections of the grip isolator;
FIG. 2D is an end view illustrating another embodiment of the grip isolator and shows the multiple buckling sections;
FIG. 2E is a sectioned side view illustrating an embodiment of a grip isolator for a vibrating device as seen along lines 2E--2E in FIG. 2D;
FIG. 2F is an enlarged end view with a portion broken away illustrating the means for restraining torsional motion for the vibrating device;
FIG. 2G is a partial end view illustrating one buckling section of the grip isolator in the buckled state;
FIG. 2H is an enlarged partial end view illustrating the dimensions of the buckling section of the grip isolator;
FIG. 3A is a top view of a first embodiment of the buckling isolator;
FIG. 3B is a sectioned side view of the buckling isolator as seen along line 3B--3B in FIG. 3A;
FIG. 3C is a side view of the first embodiment of the buckling isolator shown in the buckled state;
FIG. 3D is a partially sectioned side view of another embodiment of the buckling isolator for use in a hand-held vibrating device;
FIG. 3E is an enlarged partially sectioned side view of the second embodiment of the buckling isolator;
FIG. 4A is a sectioned side view of an embodiment of a fluid and elastomer isolator installed within a hand-held vibrating device;
FIG. 4B is a sectioned side view of a second embodiment of a fluid and elastomer isolator;
FIG. 5A is a graph illustrating the spring rate characteristics exhibited by the buckling isolator within the hand-held vibrating device;
FIG. 5B is a graph illustrating the spring rate characteristics exhibited by the fluid and elastomeric isolator within the hand-held vibrating device;
FIG. 6A is a sectioned side view of a third embodiment of an isolator for use in hand tools employing a tuned vibration absorber;
FIG. 6B is a sectioned side view of a fourth embodiment of an isolator for use in hand tools which uses a hybrid absorber/buckling column isolator;
FIG. 6C is a graph illustrating the intended performance characteristics of the third embodiment of isolator within the hand-held vibrating device;
FIG. 6D is a graph illustrating the actual performance characteristics exhibited by the third embodiment of isolator within the hand-held vibrating device;
FIG. 7A is a perspective view of a fifth embodiment of the isolator of the present invention depicting the use of metallic bucking springs;
FIG. 7A' is an enlarged cross-sectional side view of an individual spring element of the isolator of FIG. 7A with the buckled position shown in dotted line;
FIG. 7B is a perspective view of a sixth embodiment of the isolator of the present invention depicting a second form of metallic buckling spring;
FIG. 7B' is an enlarged cross-sectional side view of an individual spring element of the isolator of FIG. 7B with the buckled position shown in dotted line;
FIG. 7C is a perspective view of a seventh embodiment of the isolator of the present invention depicting a third form of metallic buckling spring; and
FIG. 7C'is an enlarged cross-sectional side view of an individual spring element of the isolator of FIG. 7C with the buckled position ghosted in.
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1A, an embodiment of a buckling isolator 20A and a separate embodiment of a grip isolator 30A are shown installed in the environment of the hand-held vibrating device 10. The vibrating device 10 that is used to illustrate the present invention is a pneumatic air hammer, but the buckling isolator 20A and grip isolator 30A are equally effective, when properly situated, for any type of hand-held vibrating equipment or device. The pneumatic air hammer or vibrating device 10 in the present invention includes a tool bit 32 (FIG. 1B) which is preferably steel and which contacts the work piece (not shown). The vibrating device 10 also includes a handle 34 which is grasped by a first rear hand of the user. Further, the handle attaches to a sleeve 36 that is preferably cylindrically shaped. However, a sleeve integrated into a handle may be envisioned, as well.
One end of the buckling isolator 20A attaches to the handle 34 by way of bolts or other fastening means 37. The other end of buckling isolator 20A is attached to the tool body 38 by bolts or other fastening means 37. The buckling isolator 20A attaches between the tool body 38 and the handle 34 and allows the tool body 38 to deflect axially and thus acts as an isolator spring between the tool body 38 and handle 34. The axial motion is limited by a snubber 48. The snubber consists of a collar 47 which is part of or alternatively contact the ends of the collar 47 at the excursion limits. By way of example and not by limitation, the snubber 48 constrains the movement in the axial direction to 0.4 inch (in.) maximum compression deflection and 0.1 inch (in.) tensile deflection.
In order to maintain control of the vibrating device 10, it is important to keep the torsional and cocking stiffness of the vibrating device 10 as high as possible. Contrarily, in order to isolate the user from vibration, it is desirable to keep the axial stiffness as low as possible. These are competing criteria and usually both are not obtainable because, as the axial stiffness is reduced, by reductions in elastomer thickness and/or modulus, the cocking and torsional stiffnesses are also reduced. Low cocking and torsional stiffnesses make for poor tool control.
In the present invention, the tool body 38 is restrained from cocking relative to the sleeve 36 and, thus also, the handle 34 by way of sliding surfaces 40A and 40B which are axially spaced and which lightly contact the outer periphery 42 of the tool body 38. The sliding surfaces 40A and 40B and/or outer peripheries 42 are coated with Teflon® or other suitable means for reducing friction. This allows the tool body 38 to slide telescopically within the sleeve 36 and compress axially the elastomeric buckling section 44A of the buckling isolator 20A, thus reducing the spring rate in the axial direction within a working thrust load range to be described later.
As shown in FIG. 2F, in order to restrain torsional motion, splines or keys 50 which are added on the tool body 38 are received within grooves 52 formed in the sleeve 36. Together, the splines or keys 50 and grooves 52 comprise the means for restraining torsional movement 56, while allowing unrestricted axial motion. Other means of restraining torsional movement such as flats and non-round shapes are also acceptable. Again, referring to FIG. 1A, the sliding surfaces 40A and 40B together with the outer periphery 42 of the tool body 38 act as the means for restraining cocking motion while allowing relatively unrestricted axial motion.
The cocking and torsional modes are restrained, but axial displacement of the tool body 38 relative to the handle 34 can occur by compressing the buckling isolator 20A. The buckling isolator 20A achieves a much lower axial spring rate than prior art devices. When the user provides an axial force to the handle 34 along the axial axis, that force will compress the buckling isolator 20A and cause the elastomeric section 44A to undergo buckling. The elastomeric section 44A will experience a high static stiffness initially, yet as more force is applied and the elastomeric section 44A starts to buckle, the force needed to maintain the section in buckling falls off dramatically. After reaching this fall off point, or what is known as the "knee" in the spring rate curve, an operating zone (or working thrust load range) is reached where the spring rate is very low. Normally, within this zone the spring rate is in the range of 2 to 30 times lower than the initial static spring rate. It can even drop off more with proper sizing of the elastomeric section 44A. Within this operating range, maximum vibration isolation is achieved. A full description of buckling elastomer sections can be found in U.S. Pat. No. 3,798,916 to Schwemmer, U.S. Pat. No. 3,948,501 to Schwemmer, U.S. Pat. No. 3,280,970 to Henshaw, and Re 27,318 to Gensheimer which are all hereby incorporated by reference herein.
By way of example and not by limitation, the initial static spring rate of the buckling isolator is 375 lbf/in at 5 lbf load and at the operating load of 40 lbf the spring rate is 15 lbf/in. The buckling isolator 20A provides axial vibration isolation superior to the prior art compression-type isolators and fluid damped mounts for vibrating hand-held devices. However, in some instances, radial vibration can impart severe vibration to the user, in spite of the isolator 20A as a result of the key 50 hammering in keyway 52.
In FIGS. 2A and 2B, a first embodiment of a grip isolator 30A is shown. The grip isolator 30A functions both as a grip for the user to grasp the vibrating device 10 and also as a radial and axial isolator to isolate the user from radial and axial mechanical vibration emanating therefrom. The grip isolator 30A can be installed on the vibrating device 10 at an point which is convenient, such as tool body 38 (FIG. 1A). Alternatively, the grip isolator 30B could encircle the tool 32 (FIG. 1B). In some instances, this latter embodiment will be preferred as many operators desire to grip the hammer 10 as far forward as possible for improved balance.
The grip isolator 30A includes a body of elastomer 46B, a multiple number of buckling sections 44B extending radially inward from the body of elastomer 46B toward a central axis A. As shown in FIG. 2C these buckling sections 44B have a length L (in.), a width W (in.), a thickness t (in.), and are molded of elastomer with a shear modulus G (psi). The parameters L, W, t, and G can be chosen to provide the optimum buckling for the vibrating device 10 (FIG. 1A). The buckling sections are formed by substantially parallel slots 45 extending into said body of elastomer 46B. As fully set forth in the two Schwemmer patents and the patents to Henshaw and Gensheimer, in order to exhibit buckling, the sections must have a length to thickness ratio L/t 3 2.
Prior art grips have included foam rubber construction which has excellent vibration isolation characteristics; however, these grips quickly deteriorate due to abrasion, are of poor overall strength, and are subject to being contaminated with oil. Prior art natural rubber grips were more rugged than foam grips, but failed to properly isolate the user's hand. The present invention grip isolator 30A or 30B is slid over the member to be isolated 32 or 38, such that in its static form, the buckling sections 44B are buckled and the user is optimally isolated from the vibration (See FIG. 2G). The present invention provides a rugged grip that is capable of isolating the user from vibration.
A second embodiment of grip isolator 30B is illustrated in FIG. 2D and 2E. This embodiment is comprised of a body of elastomer 46C, but the buckling sections 44C are formed by a series of substantially parallel cores or bores 58 extending into the body of elastomer 46C. The large bore 60, as installed, has an interference fit with the member to be isolated, such as a tool bit 32 (FIG. 1B) or tool body 38 (FIG. 1A). An intermediate wall 59 (FIG. 2E) of elastomer provides radial stability to bores 58 while permitting axial softness of the isolator 30B. By pressing the grip isolator 30B over the member to be isolated, the buckling sections 44C (FIG. 2D) are buckled and as a result the radial spring rate is lowered substantially.
In this embodiment, the buckling sections 44C have low combined axial stiffness to provide isolation from axial vibrations. This configuration is preferred for usage in the FIG. 1B environment where the axial vibration will be pronounced. The soft elastomer which is used preferably has a hardness in the range of 30 to 100 durometer. Ideally, soft natural rubber with a shear modulus of approximately 75 psi should be used for the grip isolator 30A and 30B.
FIG. 2H illustrates the buckling sections 44C having a length L, a width W, a thickness t, and which are molded of elastomer with a shear modulus G. The parameters L, W, t, are chosen to make the buckling section 44C buckle properly for the application. Other shapes of bored out or cored out sections can be envisioned which will allow buckling, such as rectangular, triangular, and sections which direct the buckling direction.
A view of a first embodiment of buckling isolator 20A is illustrated in FIG. 3A and 3B. The isolator 20A is comprised of a first end member 62, a second end member 64, and a body of elastomer 46A integrally bonded to the members 62 and 64. The body of elastomer 46A includes a buckling section 44A which buckles outwardly under the application of load as shown in FIG. 3C.
FIGS. 3D and 3E illustrate another type of buckling isolator 20B for use in a hand-held vibrating device 10. This buckling isolator 20B has a slight taper from either end member 62 and 64 on the outside surface of the body of elastomer 46D such that the center most portion is thinnest. This is to promote inward directional buckling of the W-shaped buckling section 44D. When the extended throw available with the FIG. 1A embodiment is unnecessary, this second embodiment offers a more compact envelope.
In FIG. 4A a fluid-and-elastomer version of the buckling isolator 20C is shown. The buckling isolator 20C includes a first variable volume fluid chamber 68, a second variable volume fluid chamber 70 and a fluid passageway 72 which allows for fluid communication between the chambers 68 and 70. Fluid 74 substantially fills, and is contained within, the chambers 68 and 70 and the fluid passageway 72. The theory of operation of the fluid and elastomer isolator is simple. As the air pulses enter the device 10 through an air passage or air supply tube 80A and excite the tool body 38, the tool body 38 oscillates correspondingly. The dynamic oscillation of the tool body 38 relative to the handle 34 will cause the buckling section 44E to flex dynamically. This will pump fluid 74 from one chamber 68 to the other 70. Because of the differential in area between the fluid passageway 72 and the fluid chambers 68 and 70, and the transmissibility at resonance of the fluid 74, the fluid 74 can be accelerated to very large velocities as it flows through the passageway 72 and can generate significant phased counter inertial forces. As a result, with proper tuning, these inertial forces can be tuned to provide a dynamic stiffness notch at a predominant operating frequency. This will substantially reduce the vibration transmitted to the user.
In this embodiment, a first flexible element 76 which defines a portion of the first variable volume fluid chamber 68 is a fabric reinforced diaphragm. The diaphragm accommodates temperature expansion and allows static displacement of fluid from one chamber to another. A second flexible element 78 which defines a portion of the second variable volume fluid chamber 70 includes the buckling section 44E. The air passage 80A is a flexible bellows such as a steel spring bellows and passes through the second variable volume fluid chamber 70.
In FIG. 4B a second embodiment of a fluid and elastomer version of the buckling isolator 20C is shown. The only difference between the embodiment shown in FIG. 4A and this one is in the construction of the air passage 80B. In this embodiment, the air passage 80B slides telescopically within a tube 82 attached to the tool body. A pair of seals 84 prevents fluid 74 from escaping from the chamber 68 and air from entering the chamber 68.
In FIG. 5A a performance curve of the buckling isolators 20A, 20B, and 20C are shown. The performance curve plots axial load in pounds force (lbf.) on the vertical axis versus deflection in inches (in.) on the horizontal axis and is split into five different sections labeled 1 to 5. Section 1 of the curve illustrates the initial-low-strain spring rate, prior to the occurrence of any buckling. Section 2 illustrates the onset of buckling where the spring rate begins to fall off. Section 3 illustrates the optimum operating point where the tangent spring rate is the lowest. Section 4 is where the buckling section is so buckled that it begins to behave as a compression element and substantially stiffens. Section 5 is where the buckling section is bottomed out and begins to snub.
In FIG. 5B a performance curve of a fluid and elastomer version of the buckling isolator 20C is shown. The curve section labeled 1 is the low frequency dynamic stiffness which is essentially the contribution due to the elastomer stiffness. Section 2 is the notch section. The notch is tuned to coincide with the fundamental frequency of input vibration by varying the functional characteristics of the fluid portion, e.g., the length of the inertia track, density of the fluid, etc. Section 3 is the peak dynamic stiffness and coincides closely with the fluid natural frequency. Section 4 is the high frequency stiffness after the fluid dynamically locks up and no longer flows through the fluid passageway.
In FIG. 6A is described another embodiment of isolator 20F. This isolator 20F is useful for reducing the vibration transmitted to a user from a hand-held device and the like. In this embodiment, like numerals denote like elements as compared to the previous embodiments. The device is comprised of a handle 34F, a sleeve 36F attached to said handle 34F, and a tool body 38F similar to the previous embodiments. The main difference is that the reduction in spring rate within an operating range of frequency is accomplished by incorporating a first and second elastomer 84 and 85 and a suspended, tuned mass 86.
The first elastomer element 84 is a pure shear element, i.e., under axial loading along axis Y--Y, the first elastomer section 84 is placed in pure shear. The second elastomer section 85 is preferably also a pure shear section, but either could be a compression loaded section as well. The first elastomer section 84 is integrally and chemically bonded to the first end member 62F and the second end member 64F. The first end member includes a sleeve portion 87 and an attached plate portion 89 which is secured to the handle 34F. The second end member 64F is comprised of a sleeve portion 87' and an attached plate portion 89' which, in turn, attaches to the tool body 38F. The first elastomer section 84 provides a flexible connection between, and acts to isolate, the handle 34F from the tool body 38F by allowing relative axial motion therebetween. Snubber 48 limits the axial motion in a similar manner as the previous embodiments. The mass 86 is also integrally attached to and chemically bonded to the first end member 62F.
Mass 86 and second elastomer element 85 are tuned such that the mass 86 resonates at a frequency just above the frequency of interest, i.e., the motor frequency or air hammer frequency. The tuned frequency or natural frequency fn in Hz of the mass 86 can be approximated by the relationship fn=1/2 1 (K/M) 1/2 , where K is the shear stiffness (lb/in) in pounds per inch of the second elastomer element 85, and M is the mass of the mass 86. By way of example and not by limitation, the shear stiffness K=100 pounds per inch (lb/in), mass M=1 lb mass in pound seconds per inch squared (lb sec/in 2 ), and the resonant frequency is about 31 Hz. By tuning the natural frequency at 31 Hz and including this mass 86 on a typical chipper hammer, the operating range, for example, will be between about 28 and 31 Hz. Normally, the input vibration for a air hammer is about 30 Hz. This provides a reduction in the transmission of mechanical vibration to the user within the frequency range. Fasteners 37F and 37F' secure the first end member 62F and second end members 64F to the handle 34F and tool body 38F respectively.
FIG. 6B is another embodiment of isolator 20G. This embodiment is similar to the embodiment in FIG. 6A except the first elastomer element 84G is a buckling section. Buckling sections are described in the art in U.S. Pat. Nos. 3,948,501, 3,798,916, 3,280,970, and Re 27,318. The element 84G buckles radially inward (as shown in dotted lines) upon application of axial load. The mass 86 and second elastomer element 85 function as a tuned absorber as in the previous embodiment. In this case, the buckling section is preferably integrally and chemically bonded between the cup-shaped first end member 62F' and plate-like second end member 64F'. Upon buckling, the spring rate of the buckling section will drop off dramatically (by as much as 30 times or more) and provide a low spring rate for isolation of the user within a deflection range. The tuned absorber is comprised of mass 86 and elastomer element 85, which can further reduce the vibration imparted to the user.
FIG. 6C is an illustration of the intended or analytical performance of the tuned absorber embodiment of isolator 20F of FIG. 6A. The solid line 88 indicates the analytical performance of the system without a tuned absorber and including a shear type first elastomer element 84 (FIG. 6A). The resonance at about 9 Hz is the system resonance. The curve indicated at 90 is for a system including a very small mass for the tuned mass 86 (FIG. 6A). The curve 92 illustrates a mass 86 (FIG. 6A) used it the experiment of about 1 (lb) pound in weight. Theoretically, for this example, a range of improved isolation can be seen between about 28-31 Hz where the peak accelerations are reduced.
FIG. 6D is an illustration of the actual experimental performance of the tuned absorber embodiment of isolator 20F of FIG. 6A. The solid line 94 indicates the performance in peak acceleration in inches per second squared (in/s 2 ) as a function of frequency (Hz). As expected, the peak accelerations are substantially reduced within the operating range of about 28-31 Hz.
FIG. 7A is an illustration of another embodiment of buckling isolator 20H. The isolator 20H buckles radially outward under application of load such that the spring rate is reduced within a deflection range in a similar manner as the aforementioned elastomer embodiments. The isolator 20H is comprised of a series of buckling elements 95H extending between end portions 96H and 97H. End portions 96H and 97H attach to tool handle 34H and tool body 38H, respectively. Preferably the buckling elements 95H have a curvature formed thereon for biasing the buckling in one direction. The buckling elements 95H are preferably metal and are formed from a stamped and bent sheet and are preferably made of spring-type steel or are made into spring-type steel through an appropriate heat treatment operation. As shown in FIG. 7A', upon application of axial load, the buckling element 95H will buckle radially outward as shown in dotted lines. Upon buckling, the spring rate of the isolator drops off dramatically.
FIG. 7B is an illustration of another embodiment of buckling isolator 20J. This embodiment is functionally similar to the FIG. 7A embodiment except that the buckling elements 95J are not part of a stamped plate. The elements 95J are individual and preferably metal members of wire shape with a curvature formed thereon. The preferable cross section is rounded. The wire-type buckling elements 95J are fitted in recesses in end portions 96J and 97J. Again, preferably the buckling members 95J are made from spring steel or the like. Upon buckling, the axial spring rate is substantially reduced.
FIG. 7C is an yet another illustration of an embodiment of buckling isolator 20K. In this embodiment, the buckling elements 95K are strip members with coiled or wrapped ends for accepting pins 99K. The members 95K preferably have a curvature along their length to initiate or bias buckling in the proper direction. The members 95 are connected to clevises 98K or the like such that a pin joint is formed by pins 99K interacting with coiled ends at the interface with end portions 96K and 97K. FIG. 7C' illustrates the buckling element 95K in its buckled form. Upon buckling, the axial spring rate is substantially reduced.
In summary, the present invention relates to a vibration isolator for use on a hand-held vibrating device for reducing the mechanical vibration imparted to the user. One embodiment of isolator attaches between the tool body and the handle reduce the mechanical vibration within a range of frequency or deflection range. Embodiments are drawn to buckling elastomer type and buckling metal type isolators, tuned fluid isolators, and tuned mass isolators for reducing the spring rate within a range. In the buckling isolator embodiments, the buckling means attaches between a handle for being grasped by said user and a tool body and the initial spring rate is reduced within an operating range upon application of load. In the fluid isolator, a tuned fluid is used to generate counter inertial fluid forces for reducing the transmitted forces within a frequency range, while in the tuned absorber embodiment, the tuned mass and second spring are tuned to provide the vibration reduction within a frequency range. The grip isolator embodiment comprises multiple buckling means extending radially inward toward a central axis of said hand-held vibrating device for exhibiting an installed radial spring rate in a buckled condition which is lower than a spring rate in a non-installed condition. All of these isolators are intended to reduce the mechanical vibration imparted to the user and reduce or eliminate the incidence of "white hand" or other physiological deterioration.
While several embodiments of the present invention have been described in detail, various modifications, alterations, changes and adaptations to the aforementioned may be made without departing from the spirit and scope of the present invention defined in the appended claims. It is intended that all such modifications, alterations and changes be considered part of the present invention.
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An isolator for use in a hand-held vibrating device for providing optimum vibration isolation by utilizing elastomeric sections. Six embodiments are shown which utilize elastomer sections to enhance vibration isolation along an axial direction of vibration. A first embodiment includes a frustoconical section, while the second employs a W-shaped buckling element. A third embodiment includes use of a tuned fluid inertia which is tuned to substantially coincide with a predominant operating frequency of the vibrating device and produces forces to substantially reduce the vibration transmission, while three other embodiments employ metallic buckling springs. Another embodiment employs a tuned vibration absorber and still another combines a tuned mass with a buckling column.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority of German application No. 102005020315.9 filed May 2, 2005, which is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
The present invention relates to a hearing device remote control unit or relay station with a data interface for the transmission of data from/to a data network. The present invention also relates to a corresponding use of a hearing device remote control unit.
BACKGROUND OF THE INVENTION
Until now, known technical implementations of home networks or alarm systems for the hearing-impaired have been unable to communicate directly with conventional hearing device systems. Existing systems use either an additional device with an optical light signal or vibration signal in order to notify the hearing-impaired person of an event in the home or house network (doorbell, telephone, alarm clock, baby monitor or the like). Alternative systems also offer the option of establishing the acoustic connection to a hearing device via a plug-in module (MXL) or induction loop. However, MLX systems are designed as an additional module for a broadband audio transmission and are thus clearly oversized for the present signaling application, particularly with regard to power consumption and size.
Patent DE 103 45 173 B3 discloses a modular remote control unit for hearing aid devices. This remote control unit may have resources for transferring data between the remote control unit and another device other than the hearing aid device. For example, such a remote control unit may be used to establish a connection between the hearing aid device and a data network, e.g. Bluetooth or wireless LAN.
SUMMARY OF THE INVENTION
The object of the present invention is to support the transmission of information between components of a network and a hearing device.
This object is achieved according to the invention by a hearing device remote control unit or a relay station, which may be linked inductively, in particular to a hearing device, using a data interface for the transmission of data from/to a data network, said data network being a low-rated network in particular for domestic appliances. The remote control unit thus functions as an intermediary between the network and the respective hearing devices, enabling the hearing devices to participate fully in the network. A network may be a house or home network, but may also be any other local or mobile radio network. Such a network may be used for a motor vehicle, public facilities and buildings, airports, train carriages, rail stations etc.
Accordingly, the use of a hearing device remote control unit is therefore proposed for controlling one or more domestic appliances of a low-rated home network and/or for receiving data from said domestic appliance or appliances via the low-rated home network.
In contrast to existing solutions, the solution according to the invention does not require any costly additional modules for the hearing devices. The modules for connection to the home network are accommodated in the remote control unit or relay station and may therefore be operated from a battery or power pack, which is clearly more powerful than conventional hearing device batteries. The additional functions with regard to the home network connection may therefore be implemented using existing remote controllable hearing device systems with minimal requirements in terms of space and power consumption.
A further advantage of the hearing device remote control unit according to the invention or use of said hearing device remote control unit according to the invention consists in that the wearer can move freely, e.g. within the functional area of the home network (Smart Home System), and merely needs to carry the remote control unit on their person. Furthermore, the events to be reported in the home network may be flexibly defined by the user.
The data interface preferably guarantees a bidirectional connection to a low-rated network or home network. This means that the remote control unit may be used not only to call up the network, but also to control it.
According to one particular embodiment, the data interface conforms to the ZigBee standard. This defines not only the transmission format but also the data transfer rate. Furthermore, the term “low-rated” used in this document means that the data transfer rate is essentially defined according to the ZigBee standard.
According to a further embodiment, the hearing device remote control unit according to the invention has a display device for visually controlling the status of the domestic appliance or appliances. In particular, a multitude of status information reports may be reproduced via a display.
Furthermore, the hearing device remote control unit may have special operating elements for controlling the domestic appliance or appliances. This means that standard applications for controlling domestic appliances may be designed more conveniently for the hearing device wearer.
The hearing device remote control unit may also have a data processing device with which a predefinable number of statuses of domestic appliances in the home network may be checked when the user leaves the house. This means that the hearing device wearer does not need to use an additional device for checking the domestic appliances.
In a corresponding hearing device system having a hearing device and a hearing device remote control unit as described above, it may be possible for an acoustic signal to be triggered in the hearing device in response to incoming predefined data in the hearing device remote control unit. This means that the hearing device can easily be used for signaling statuses in the home network.
The type and/or sound of the acoustic signal may advantageously be varied depending on the source of the incoming data. Thus, for example, it may be possible to differentiate acoustically between signals in the home network that relate to a washing machine or an open window, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention will now be explained in greater detail on the basis of the attached drawing, which shows a basic sketch of a hearing device remote control unit integrated in a home network.
DETAILED DESCRIPTION OF THE INVENTION
The exemplary embodiments illustrated in greater detail below represent preferred embodiments of the present invention.
A home network HN is represented in the diagram by a washing machine W, a lamp L and a radiator H with thermostat. These devices may intercommunicate in any way via the home network HN. The home network may, for example, be a network according to the ZigBee standard, a proprietary home network or a special solution for the hearing-impaired, in which a low-rated data transmission on the scale off the ZigBee standard or below is always used.
According to the invention, a hearing device remote control unit FB with a monodirectional or bidirectional data connection to hearing devices HG 1 and HG 2 , is integrated in the home network HN. The hearing devices HG 1 and HG 2 are not actually components of the home network and communicate with one another or with the remote control unit FB by means of conventional transmission technology. Since the remote control unit FB participates fully in the home network, with transmission and reception functions, the corresponding standard components of the respective home network system are integrated in it.
The remote control unit FB, as a component of the home network HN, may respond to corresponding events and may trigger a corresponding acoustic signal to alert the user, for example via a wireless digital connection to the hearing device HG 1 , HG 2 . The type and sound of this signal may be adapted to the character of the respective source L, W, H. For example, a doorbell or a telephone, which are part of a home network, may communicate with the hearing device remote control unit FB in this way. An incoming telephone call or activation of the doorbell may thus be detected by the remote control unit FB and triggers a command in the hearing device, which is announced acoustically by the respective specific signal tone in the hearing device.
In a further exemplary embodiment of the hearing device system according to the invention, a user-definable quantity of statuses is checked using the existing home network HN when the user leaves the house. Thus, for example, the system checks whether the heating, the water taps, the cooker rings and the lights are switched off. In the event of an unwanted status, this can be displayed on the remote control unit FB provided it has a corresponding display element. In addition, the hearing device wearer may also be acoustically notified of the status or statuses automatically by means of a signal tone. If the remote control unit FB also has operating elements, then the individual appliances in the home network HN may be controlled accordingly. It is also possible to provide a voice control system instead of operating elements for touch control. The microphone and transmission technology of the hearing system are used as the user interface for this purpose. Irrespective of the control type, the remote control unit is thus afforded an additional functionality—namely, in addition to the control of the hearing system, the control of the home automation system.
Instead of the remote control unit, a relay station may also be connected to the hearing devices on one side and to the home automation system on the other. Thus, for example, the relay station may be used by the home network for the inductive transmission of audio signals to the hearing device, and also in order to trigger specific signal tones in the hearing device. Status information about the home network may also be displayed on this relay station in addition.
With the remote control unit being used as the intermediary between the network and the hearing device, therefore, it is possible for the operation and monitoring of household appliances and systems to be designed more conveniently for hearing device wearers, and for the transmission of information from components in the radio network to the hearing devices to be supported.
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The operation of appliances in a home network is to be made more user-friendly, for which purpose provision is made for the hearing device remote control unit to be integrated as a component in a network. This would, for example, enable warning signals triggered by the network to be provided in the hearing devices.
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BACKGROUND OF THE INVENTION
The present invention relates to a size for a papermaking, more specifically to an internal size which works very well in papermaking under neutral to weakly acidic conditions.
DESCRIPTION OF RELATED ART
Traditionally, rosin-based sizes have been widely used in papermaking. It has long been known that the sizing effect of rosin-based sizes is attributed to the retention-improving and water-repelling action produced by utilizing alminium sulfate added as a sizing aid. Moreover alminium sulfate becomes acidic upon dissociation, rosin-based sizes have been used under acidic conditions.
In recent years, however, there has been an increasing trend toward pH neutral papermaking due to the poor permanence of acidic papers, and the increased use of calcium carbonate content in papers as a coat color pigment, for example in printing papers.
Conventional rosin emulsion sizes consist mainly of so-called fortified rosins, i.e., rosins modified with α, β-unsaturated dibasic acids, and an anionic surfactant. The sizing effect of these rosins is lowered significantly when the pH exceeds 6.5 in the papermaking systems described above. For this reason, it is necessary to use an increased amount of size to obtain the desired degree of sizing, but this practice not only leads to higher cost due to the use of the excess size, but also poses operational problems such as foaming and pitch formation in such papermaking systems and adversely affects the quality of the finished papers.
Taking note of this situation, sizes based on an alkyl ketene dimer (hereinafter called AKD) and those based on an alkenyl succinic anhydride (hereinafter called ASA) are commonly used for neutral papermaking, but AKD and ASA are both cellulose-reactive sizes and thus pose problems related to stability. These reactive sizes are often used in a dispersion in the presence of a protective colloid such as a cationic starch, but their dispersions are poor in stability. When incorporated into a papermaking system, their tackiness increases with the collapse of the dispersion, resulting in major problems such as the staining of a papermaking equipment and thus their use demands an improvement.
In parallel to investigations aimed at improving the AKD and ASA sizes described above, the use of rosin-based neutral sizes has been proposed. For example, see Japanese Patent Publication Open to Public Inspection (hereinafter referred to as Japanese Patent O.P.I. Publication) Nos. 250297/1987 (equivalent to U.S. Pat. No. 4,842,691) and 120198/1988 (equivalent to U.S. Pat. No. 4,943,608) and Japanese Patent Examined Publication No. 36629/1990 (equivalent to U.S. Pat. No. 4,540,635).
Rosin-based sizes incorporating various rosin esters have long been known. For example, U.S. Pat. No. 3,044,890 discloses fortified rosin dispersions prepared by esterifying the base rosin with a polyhydric alcohol such as glycerol, propylene glycol or pentaerythritol, and British Patent No. 859789 discloses mixtures of fortified rosin and aminoalcoholesterified rosin. However, none of these patents show a noticeable effect; similarly with the type of rosin ester, the esterification ratio, the method of dispersion and other to pertinent features not even considered thoroughly therein.
The art described in Japanese Patent O.P.I. Publication No. 250297/1987 comprises an aqueous dispersion containing an α, β-unsaturated dibasic acid modified rosin ester of a polyhydric alcohol comprising carbon, hydrogen and oxygen. However, the dispersion does not serve well as a size for neutral paper because its sizing effect is lowered significantly at pH levels above 7 in papermaking.
In contrast to the above-mentioned art of British Patent No. 859789, which uses a mixture of fortified rosin and an alkanolamine ester of a rosin, the art described in Japanese Patent Examined Publication No. 36629/1990 aims at improving the sizing around the neutral pH range by modifying the partial amino alcohol ester of a rosin with α, β-unsaturated dibasic acid. Although the size specified in Japanese Patent Examined Publication No. 36629/1990 offers better sizing around the neutral pH range than does the above-mentioned polyhydric alcohol ester of modified rosin described in Japanese Patent O.P.I. Publication No. 250297/1987, it does not yield a good emulsion nor does offer sufficient sizing around the neutral pH range.
The art described in Japanese Patent O.P.I. Publication No. 120198/1987 comprises a rosin-based emulsion size comprising fortified rosin and a copolymer of alkyl (meth)acrylate ester and/or a styrene compound and alkylaminoalkyl (meth)acrylate ester or alkylaminoalkylamide, but it does not serve well as a size for neutral paper because its sizing quality around the neutral pH range is low.
SUMMARY OF THE INVENTION
The present invention has been developed with an aim of solving the aforementioned problems in the prior art, and provides a good size which is excellent in stability and which quickly exhibits a sizing effect especially in the neutral pH range.
The size composition of the present invention is a rosin-containing size for papermaking characterized in that a surfactant represented by the formula (1) shown below in a ratio of 1 to 10 wt % of the solids in the size and casein in a ratio not exceeding 10 wt % of the solids in the size are added to, and dispersed in, a mixture of an esterification product of rosin and an alkanol tertiary amine, which is produced by adding the alkanol tertiary amine in a ratio of 1.5 to 10 wt % of the total rosin content in the size, and a fortified rosin produced by adding an α, β-unsaturated carbonyl compound in a ratio of 3 to 11 wt % of the total rosin content in the size to reach a solid content of 20 to 60 wt % in the size composition. ##STR1##
In the above formula (1) R represents a C 10-24 alkylphenyl group or a linear or branched alkyl group; n represents an integer of 6 to 20; X and Y independently represent H or SO 3 M; M represents sodium, potassium or an ammonium group.
Examples of the rosin used in the present invention include gum rosin, tall oil rosin and wood rosin. Examples of the alkanol tertiary amine include triethanolamine, tripropanolamine, triisopropanolamine, N-isobutyldiethanolamine and N-normal-butyldiethanolamine. Esterification of rosin and alkanol tertiary amine can be carried out by thermally melting the rosin and thereafter drop by drop addition of the alkanol tertiary amine to the molten rosin. An appropriate esterification temperature is between 190° and 230° C.
The modification of rosin with an α, β-unsaturated carbonyl compound can be achieved by a known method. Examples of α, β-unsaturated carbonyl compounds include maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, acrylic acid and methacrylic acid.
These rosins may be disproportionated, and may be pre-treated with formaldehyde etc. Additional rosin may be added after reaction within the range allowed by the present invention. It is also possible to add ordinary extenders, such as waxes and various rosin esters other than the rosin ester with alkanol tertiary amine, in ratios up to 10 wt % of the desired composition.
The surfactant represented by the formula (1), a key component of the size composition of the present invention, is obtained by condensing alkylphenol or alcohol and ethylene oxide by a known method and converting the resulting condensate into a halfester of sulfosuccinic acid by a conventional method. Commercially available products of the compound represented by the formula (1) are AEROSOL® A-103 [with alkylphenol for R in the formula (1)], a product of American Cyanamid Company, and SOFTANOL® MES-12 [with higher secondary alcohol for R in the formula (1)], a product of Nippon Shokubai Kagaku Kogyo Co., Ltd., both of which can be used as additives for the composition of the present invention.
In emulsion sizes, the sizing effect and size stability are critical factors. Even when a mixture of a rosin esterification product and a rosin fortified with an α,β-unsaturated carbonyl compound is dispersed in casein as such by the ordinary emulsion inversion method to yield a size composition, the resulting size composition is not satisfactory in sizing and stability. The desired effect of the present invention is obtained by adding a surfactant represented by the formula (1) involved in the present invention.
The size composition of the present invention includes the aforementioned rosin reaction product described in British Patent No. 859787, but the dispersion according to the present invention differs from complete saponified sizes in size morphology and sizing effect. In addition, it was found that the dispersion of each of components of the size of the present invention, namely the alkanol tertiary amine ester of rosin and the fortified rosin, is extremely poor in sizing performance near the neutral pH range, while the size obtained by mixing these components in a ratio according to the present invention and dispersing the mixture shows an excellent sizing effect, based on which finding the present invention was developed.
The size composition of the present invention is compositionally different from the α,β-unsaturated dibasic acid modified product of the alkanolamine ester of rosin according to the art described in Japanese Patent Examined Publication No. 36629/1990. Also, problems posed by the casein dispersion disclosed in Examples of Japanese Patent Examined Publication No. 36629/1990, such as insufficient stability and sizing due to extremely great particle size and coloring of the reaction product during modification reaction of the alkanolamine ester of rosin with α,β-unsaturated dibasic acid, can be solved by the size composition of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention is hereinafter described in more detail by means of the following examples of the preferred embodiments. In the description below, "part(s)" indicates "part(s) by weight" unless otherwise stated.
SYNTHESIS OF ROSIN DERIVATIVES
Synthesis Example 1
100 parts of tall oil rosin (acid value 167) was molten by heating at 210° C., and 10 parts of triethanolamine was added drop by drop over a period of 20 minutes (COOH:OH=1:0.68). While continuing dehydration at constant temperature, a reaction was carried out for 5 hours. The resulting resin had an acid value of 63.
Synthesis Example 2
100 parts of tall oil rosin (acid value 167) was molten by heating at 210° C., and 17.6 parts of maleic anhydride was charged in separate additions over a period of 1 hour, and this temperature was kept for 2 hours. The resulting resin had an acid value of 226.
Comparative Synthesis Example 1
100 parts of tall oil rosin (acid value 167) was molten by heating at 210° C., and 9.4 parts of maleic anhydride was charged in separate additions over a period of 20 minutes, followed by a reaction at this temperature for 1 hour. Then, 6 parts of triethanolamine was added drop by drop over a period of 20 minutes. The mixture was heated to 230° C. and kept at this temperature for 3 hours. The resulting resin had an acid value of 148.
Comparative Synthesis Example 2
100 parts of tall oil rosin (acid value 167) was molten by heating at 250° C., and 8 parts of glycerol was added drop by drop over a period of 20 minutes. While continuing dehydration at a constant temperature, a reaction was carried out for 10 hours. Then, the temperature was decreased to 210° C., and 9 parts of maleic anhydride was carefully added gradually. After the completion of the addition of maleic anhydride, the mixture was kept at a constant temperature for 90 minutes. The resulting resin had an acid value of 78.4.
Comparative Synthesis Example 3
100 parts of tall oil rosin (acid value 167) was molten by heating at 210° C., and 6.4 parts of maleic anhydride was charged in separate additions over a period of 1 hour. The mixture was kept at this temperature for 2 hours. The resulting resin had an acid value of 191.
Comparative Synthesis Example 4
100 parts of tall oil rosin (acid value 167) was molten by heating at 200° C., and 5.3 parts of fumaric acid was charged in separate additions over a period of 1 hour. The mixture was kept at this temperature for 2 hours. The resulting resin had an acid value of 205.
PREPARATION OF AQUEOUS DISPERSIONS
Example 1
40 parts of the resin of Synthesis Example 1 and 60 parts of the resin of Synthesis Example 2 were molten at 180° C. and cooled to 130° C. 12 parts (active ingredient 3 parts) of SOFTANOL® MES-12, as the surfactant, was gradually added to this molten resin with stirring, and then 50 parts of a 10% casein solution (5 parts of casein, 2.6 parts of 25% aqueous ammonia, diluted with water to reach a total quantity of 50 parts) was gradually added drop by drop. 60 parts of hot water at 95° C. was gradually added drop by drop to invert the mixture to an oil-in-water emulsion. Then, after 130 parts of hot water was added, the solution was rapidly cooled to 30° C. The resulting emulsion had a solid content of 31%.
Example 2
50 parts of the resin of Synthesis Example 1 and 50 parts of the resin of Synthesis Example 2 were molten at 180° C. and cooled to 130° C. 12 parts (active ingredient 3 parts) of SOFTANOL® MES-12 was gradually added to this molten resin with stirring, and then 50 parts of a 10% casein solution (5 parts of casein, 1.9 parts of 10% NaOH, diluted with water to reach a total quantity of 50 parts) was gradually added drop by drop. 60 parts of hot water at 95° C. was gradually added drop by drop to invert the mixture to an oil-in-water emulsion. Then, after 130 parts of hot water was added, the solution was rapidly cooled to 30° C. The resulting emulsion had a solid content of 31%.
Example 3
60 parts of the resin of Synthesis Example 1 and 40 parts of the resin of Synthesis Example 2 were molten at 180° C. and cooled to 130° C. 8.8 parts (active ingredient 3 parts) of AEROSOL® A-103 was gradually added to this molten resin with stirring, and then 70 parts of a 10% casein solution (4 parts of casein, 2.0 parts of 25% aqueous ammonia, diluted with water to reach a total quantity of 70 parts) was gradually added drop by drop. 40 parts of hot water at 95° C. was gradually added drop by drop to invert the mixture to an oil-in-water emulsion. Then, after 130 parts of hot water was added, the solution was rapidly cooled to 30° C. The resulting emulsion had a solid content of 31%.
Example 4
60 parts of the resin of Synthesis Example 1, 60 parts of the resin of Synthesis Example 2 and 80 parts of formaldehyde-treated tall oil rosin were dissolved in 200 parts of toluene. 12 parts (active ingredient 3 parts) of SOFTANOL® MES-12, 40 parts of a 10% aqueous solution of casein (4 parts of casein, 1.5 parts of 10% NaOH, diluted with water to reach a total quantity of 40 parts) and 340 parts of ion exchange water were added to this solution, and they were mixed by using a homomixer at 40° C. Subsequently, the dispersion was passed through a piston type high pressure mechanical emulsifier (200 kg/cm 2 ) once to yield a fine dispersion. Then, the toluene and a small amount of water were distilled off under the reduced pressure to yield an aqueous dispersion. The resulting emulsion had a solid content of 35%.
Example 5
140 parts of the resin of Synthesis Example 1 and 60 parts of the resin of Synthesis Example 2 were dissolved in 200 parts of toluene. 24 parts (active ingredient 6 parts) of SOFTANOL® MES-12 and 365 parts of ion exchange water were added to this solution, and they were mixed by using a homomixer at 40° C. Subsequently, the dispersion was passed through a piston type high pressure mechanical emulsifier (200 kg/cm 2 ) once to yield a fine dispersion. Then, the toluene and a small amount of water were distilled off under the reduced pressure to yield an aqueous dispersion. The resulting emulsion had a solid content of 35%.
Comparative Example 1
55 parts of the resin of Synthesis Example 1 and 45 parts of the resin of Synthesis Example 2 were molten at 180° C. and cooled to 130° C. 16 parts (active ingredient 4 parts) of a 25% aqueous solution of sulfate ester ammonium salt of polyoxyethylene nonylphenyl ether was gradually added to this molten resin with stirring, and then 40 parts of a 10% casein solution (4 parts of casein, 1.5 parts of 10% NaOH, diluted with water to reach a total quantity of 40 parts) was gradually added drop by drop. 60 parts of hot water at 95° C. was gradually added drop by drop to invert the mixture to an oil-in-water emulsion. Then, after 130 parts of hot water was added, the solution was rapidly cooled to 30° C. The resulting emulsion had a solid content of 31%.
Comparative Example 2
55 parts of the resin of Synthesis Example 1 and 45 parts of the resin of Synthesis Example 2 were molten at 180° C. 12 parts (active ingredient 3 parts) of a 25% aqueous solution of sodium dodecylbenzenesulfonate was gradually added to this molten resin with stirring, and then 70 parts of a 10% casein solution (7 parts of casein, 1.9 parts of 10% NaOH, diluted with water to reach a total quantity of 70 parts) was gradually added drop by drop. 40 parts of hot water at 95° C. was gradually added drop by drop to invert the mixture to an oil-in-water emulsion. Then, after 130 parts of hot water was added, the solution was rapidly cooled to 30° C. The resulting emulsion had a solid content of 31%.
Comparative Example 3
50 parts of the resin Synthesis Example 1 and 50 parts of the resin of Synthesis Example 2 were molten at 180° C. and cooled to 130° C. 50 parts of a 10% casein solution (5 parts of casein, 2.6 parts of 25% aqueous ammonia, diluted with water to reach a total quantity of 50 parts) was gradually added to this molten resin drop by drop with stirring. 60 parts of hot water at 95° C. was gradually added drop by drop to invert the mixture to an oil-in-water emulsion. Then, 130 parts of hot water was added, and the solution was rapidly cooled to 30° C. The resulting emulsion had a solid content of 31%.
Comparative Example 4
100 parts of the resin of Comparative Synthesis Example 1 was molten at 180° C. and cooled to 130° C. 50 parts of a 10% casein solution (5 parts of casein, 1.9 parts of 10% NaOH, diluted with water to reach a total quantity of 50 parts) was gradually added to this molten resin drop by drop with stirring. 60 parts of hot water at 95° C. was gradually added drop by drop to invert the mixture to an oil-in-water emulsion. Then, after 130 parts of hot water was added, the solution was rapidly cooled to 30° C. The resulting emulsion had a solid content of 31%.
Comparative Example 5
200 parts of the resin of Comparative Synthesis Example 3 was dissolved in 200 parts of toluene. 100 parts (active ingredient 10 parts) of a 10% aqueous solution of sulfate ester ammonium salt of polyoxyethylene distyrylphenyl ether and 300 parts of ion exchange water were added to this solution, and they were mixed by using a homomixer at 40° C. Subsequently, the dispersion was passed through a piston type high pressure mechanical emulsifier (200 kg/cm 2 ) once to yield a fine dispersion. Then, the toluene and a small amount of water were distilled off under the reduced pressure to yield an aqueous dispersion. The resulting emulsion had a solid content of 35%.
Comparative Example 6
200 parts of the resin of Synthesis Example 1 was dissolved in 200 parts of toluene. 40 parts of a 10% casein solution (4 parts of casein, 1.5 parts of 10% NaOH, diluted with water to reach a total quantity of 40 parts) and 340 parts of ion exchange water were added to this solution, and they were mixed by using a homomixer at 40° C. Subsequently, the dispersion was passed through a piston type high pressure mechanical emulsifier (200 kg/cm 2 ) once to yield a fine dispersion. Then, the toluene and a small amount of water were distilled off under reduced pressure to yield an aqueous dispersion. The resulting emulsion had a solid content of 35%.
Comparative Example 7
100 parts of the resin of Synthesis Example 2 was molten at 180° C. and cooled to 130° C. 50 parts of a 10% casein solution (5 parts of casein, 2.6 parts of 20% aqueous ammonia, diluted with water to reach a total quantity of 50 parts) was gradually added to this molten resin drop by drop with stirring. 60 parts of hot water at 95° C. was gradually added drop by drop to invert the mixture to an oil-in-water emulsion. Then, after 130 parts of hot water was added, the solution was rapidly cooled to 30° C. The resulting emulsion had a solid content of 31%.
Comparative Example 8
100 parts of the resin of Comparative Synthesis Example 3 was molten at 180° C. and cooled to 130° C. 50 parts of a 10% casein solution (5 parts of casein, 1.9 parts of 10% NaOH, diluted with water to reach a total quantity of 50 parts) was gradually added to this molten resin drop by drop with stirring. 60 parts of hot water at 95° C. was gradually added drop by drop to invert the mixture to an oil-in-water emulsion. Then, after 130 parts of hot water was added, the solution was rapidly cooled to 30° C. The resulting emulsion had a solid content of 31%.
Comparative Example 9
100 parts of the resin of Comparative Synthesis Example 4 was molten at 180° C. and cooled to 130° C. 20 parts (active ingredient 5 parts) of a 25% aqueous solution of sulfate ester ammonium salt of polyoxyethylene nonylphenyl ether was gradually added to this molten resin with stirring. 80 parts of hot water at 95° C. was gradually added drop by drop to invert the mixture to an oil-in-water emulsion. Then, after 130 parts of hot water was added, the solution was rapidly cooled to 30° C. The resulting emulsion had a solid content of 32%.
The compositions, methods of emulsification, particle sizes and stability against resin sedimentation (a factor which affects the storage stability) of the aqueous dispersions obtained in Examples and Comparative Examples above are shown in Tables 1and 2. From the results given in Tables 1 and 2, it is evident that the size composition of the present invention is excellent in a storage stability.
TABLE 1__________________________________________________________________________Rosin Compositions Resin Composition Unsaturated Resin Charge Ratio Carbonyl Synthetic Synthetic Rosin TEA Rosin Gly Compound Resin Resin Ester Ester wt %Size Parts Parts TEA wt % Gly wt % Manh Fua__________________________________________________________________________Example 1 Synthesis 40 Synthesis 60 4.5 10.1 Example 1 Example 2Example 2 Synthesis 50 Synthesis 50 5.6 8.4 Example 1 Example 2Example 3 Synthesis 60 Synthesis 40 6.6 6.6 Example 1 Example 2Example 4 Synthesis 30 Synthesis 30 3.2 4.8 Example 1 Example 2Example 5 Synthesis 70 Synthesis 30 7.7 4.9 Example 1 Example 2Comparative Synthesis 55 Synthesis 45 6.1 7.6Example 1 Example 1 Example 2Comparative Synthesis 55 Synthesis 45 6.1 7.6Example 2 Example 1 Example 2Comparative Synthesis 50 Synthesis 50 5.0 8.4Example 3 Example 1 Example 2Comparative Comparative 6.0 9.4Example 4 Synthesis Example 1Comparative Comparative 0 9Example 5 Synthesis Example 2Comparative Synthesis 10.0Example 6 Example 1Comparative Synthesis 17.6Example 7 Example 1Comparative Comparative 6.4Example 8 Synthesis Example 3Comparative Comparative 5.3Example 9 Synthesis Example 4__________________________________________________________________________
TABLE 2__________________________________________________________________________Methods of Emulsification and Emulsion Properties Emulsion Composition Average Casein Method of Particle StorageSize % Parts Emulsification Size μm Stability__________________________________________________________________________Example 1 MES-12 3.0 5 Inversion method 0.3 Not exceed- ing 0.1%Example 2 MES-12 3.0 5 Inversion method 0.3 Not exceed- ing 0.1%Example 3 A-103 3.0 4 Inversion method 0.4 Not exceed- ing 0.1%Example 4 MES-12 1.5 4 High pressure 0.3 Not exceed- method ing 0.1%Example 5 MES-12 3.0 High pressure 0.3 Not exceed- method ing 0.1%Comparative A 4.0 4 Inversion method 0.5 0.3%Example 1Comparative B 3.0 7 Inversion method 0.5 0.3%Example 2Comparative 5 Inversion method 0.9 1.2%Example 3Comparative 5 Inversion method 0.9 1.2%Example 4Comparative C 5 High pressure 0.4 0.2%Example 5 methodComparative 4 High pressure 0.5 0.3%Example 6 methodComparative 5 Inversion method 0.4 0.5%Example 7Comparative 5 Inversion method 0.5 0.4%Example 8Comparative A 5 Inversion method 0.4 0.4%Example 9__________________________________________________________________________
With respect to Tables 1 and 2, the resin composition is expressed in values relative to the starting material rosin (wt % for TEA=triethanolamine, equivalent ratio for esters, wt % for unsaturated carboxylic acids). Manh denotes maleic anhydride, and Fua denotes fumaric acid. Emulsion A is sulfate ester ammonium salt of polyoxyethylene nonylphenyl ether (10 mol of ethylene oxide was added). Emulsion B is sodium dodecylbenzenesulfonate. Emulsion C is sulfate ester ammonium salt of polyoxyethylene distyrylphenyl ether (12 mol of ethylene oxide was added). An average particle size was measured by using CAPA-500 (centrifugal sedimentation transmission type), produced by Horiba, Ltd. The storage stability was determined after 2 months of storage at 25° C. and indicated by as the amount of sedimentary resin in % ratio.
The size compositions obtained in Examples and Comparative Examples were evaluated as to sizing performance on the basis of Stoeckigt sizing degree (second). The results are given in Table 3. It is evident from Table 3 that the size composition of the present invention offers an excellent sizing in the neutral pH range centered at pH 7.
TABLE 3______________________________________Sizing Performance Papermaking pH levelSize 6.0 6.5 7.0 7.5______________________________________Example 1 22.6 18.6 17.6 16.7Example 2 22.5 18.7 17.3 16.9Example 3 22.0 18.0 16.6 15.6Example 4 22.0 18.5 16.9 16.0Example 5 22.5 18.4 17.2 16.6Comparative Example 1 19.8 16.0 14.7 13.8Comparative Example 2 20.3 16.6 14.5 13.9Comparative Example 3 18.5 15.9 13.8 10.5Comparative Example 4 19.0 16.2 13.9 10.5Comparative Example 5 17.8 14.2 11.6 7.6Comparative Example 6 7.5 3.3 1.0 Not ex- ceeding 1Comparative Example 7 4.7 1.0 Not ex- Not ex- ceeding 1 ceeding 1Comparative Example 8 14.8 10.5 6.8 1.6Comparative Example 9 16.9 6.3 1.2 Not ex- ceeding 1______________________________________
Sizing performance was tested by using 420 ml of the L/NBKP (L/N=8/2) CSF pulp. A given amount of calcium carbonate was added to 2.5% slurry of this pulp. With stirring, cationic starch was added. Two minutes later, the size was added. Thirty seconds later, alminium sulfate was added. Thirty seconds later, a polyacrylamide-based retention aid was added. Thirty seconds later, hand-made paper (66 to 70 g/m 2 ) was prepared by the ordinary method of using a hand papermaking tester. The resulting hand-made paper was kept standing in a chamber at a constant temperature and constant humidity maintained at 20° C. and 65% humidity for 1 day and then subjected to a sizing test.
The addition ratio of cationic starch was 0.5 wt % of the absolute dry pulp weight. The addition ratio of size was 0.4 wt % of the absolute dry pulp weight for papermaking pH levels of 6.0, 6.5 and 7.0 and 0.6 wt % for a papermaking pH level of 7.5. The addition ratio of retention aid was 0.02 wt % of the absolute dry pulp weight.
The papermaking pH was adjusted so that calcium carbonate and aluminum salfate were contained in the following ratios.
pH 6.0: 1 wt % calcium carbonate and 1 wt % aluminium sulfate to pulp
pH 6.5: 2 wt % calcium carbonate and 1 wt % aluminium sulfate to pulp
pH 7.0: 10 wt % calcium carbonate and 1 wt % aluminium sulfate to pulp
pH 7.5: 10 wt % calcium carbonate and 0.5 wt % aluminium sulfate to pulp
The size composition for papermaking of the present invention shows an excellent sizing effect in the papermaking pH range above 6.5, and makes a great contribution to the production of neutral paper of good durability and good storage stability.
The various examples given above are to illustrate the size composition for papermaking of the present invention and are not to be interpreted as limitative on the invention.
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The present invention relates to a size composition which shows an excellent sizing effect in neutral to weakly acidic papermaking.
Alkanol tertiary amine and fortified rosin, incorporated in the size composition of the present invention, even when prepared as dispersions using a dispersant, are extremely poor in sizing performance in the neutral pH range, whereas the size composition obtained by mixing these components in a ratio according to the present invention and dispersing them using a surfactant specified by the present invention offers an excellent sizing in the neutral to weakly acidic pH range.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and is a divisional of U.S. patent application Ser. No. 12/972,370, filed Dec. 17, 2010, that issued on ______, 2015, as U.S. Pat. No. ______, which is incorporated herein in its entirety. This application is also related to U.S. patent application Ser. No. ______, filed on Mar. ______, 2015.
TECHNICAL FIELD
[0002] This disclosure relates to forming structures, more particularly to forming structures from interdigitated stripes of materials.
BACKGROUND
[0003] Numerous devices such as batteries, fuel cells, electrical interconnects and others can benefit from tightly spaced interdigitated stripes of dissimilar materials. The term ‘stripe’ as used here means a line or other shape of material that contains only that material. It does not mix with adjacent stripes of other materials.
[0004] Issues arise when trying to produce tightly spaced interdigitated stripes. In one approach, flow focusing using compression produces fine features of functional material in paste form. Examples of this approach can be found in U.S. Pat. No. 7,765,949, issued Aug. 3, 2010; and U.S. Pat. No. 7,799,371, issued Sep. 21, 2010. The approach taken in these patents relates to combining materials into ‘co-laminar’ flows, where three laminar flows of two different materials are brought together to form one flow, but where the two materials do not mix together. This approach suffices in application where the features are on the order of tens of microns arrayed on a millimeter scale pitch. For example, a solar cell may have a width of 156 mm and about 80 gridlines, each about 50 microns wide separated by almost 2 mm from a neighboring gridline.
[0005] In contrast, the interdigitated structures called for in the design of electrodes for energy storage devices may require micron scale features interleaved on the micron scale. For example, a typical cathode structure may involve interleaved structures that are 5 microns wide and 100 microns tall. An electrode structure may be 300 mm wide and 60,000 interleaved fingers of dissimilar materials. To dispense these materials from separate nozzles or in from multi-material slot containers would be impractical.
SUMMARY
[0006] Embodiments include a method for depositing a structure comprising interdigitated materials includes merging flows of at least two materials in a first direction into a first combined flow, dividing the first combined flow in a second direction to produce at least two separate flows, wherein the second direction is perpendicular to the first direction, and merging the two separate flows into a second combined flow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 shows a block diagram of a fluid flow of two materials into an interdigitated single flow.
[0008] FIG. 2 shows an isometric view of an embodiment of a fluid path.
[0009] FIG. 3 shows exploded view of an embodiment of a fluid co-extrusion device.
[0010] FIG. 4 shows an embodiment of a co-extrusion device and a substrate.
[0011] FIG. 5 shows an embodiment of a metal air battery having interdigitated structures.
[0012] FIGS. 6-11 show embodiments of interdigitated co-extrusions.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0013] In order to attain an interdigitated structure having micron features on a micron scale, it is possible to combine and focus two or more flows, split the combined flow into separate combined flows and then recombine and further focus the flows in repeated stages. This discussion will refer to the fluidic process that produces interdigitated flows of dissimilar fluids as ‘fluid folding.’ This discussion may also refer to the fluidic structure that performs the operations of combining, focusing, splitting, and recombining, etc., as a ‘folding cascade.’
[0014] The term ‘focusing’ as used here means the combining of two or more flows of dissimilar fluids into a combined flow that has a lateral extent across the width of the combined flow at least less than the combined lateral extent of the flows prior to combination. Typically the width of the combined flow after focusing has a lateral extent that approximately equals the lateral extent across one of the flows prior to combination. For example, if a combined flow consists of one ‘stripe’ or finger each of material A and material B, the combined flow will have a lateral extent of measure X. When the flow is split and then recombined, now having two stripes each of materials A and B interleaved, the lateral extent of this flow will have the same lateral extent X of the previous flow.
[0015] FIG. 1 shows a cross sectional diagram of a flow of two materials. All flows in FIG. 1 are in the direction of the axis that runs perpendicular to the page. All flows are shown in cross section coming out of the page. Material A, 10 , and material B, 12 , flow separately from each other at stage 14 . They then combined at stage 16 to form a first combined flow. This flow is focused at stage 18 . It should be noted that the combining and focusing may occur simultaneously or stepwise within the cascade.
[0016] At stage 20 , the combined flow splits into two separate combined flows. Note that the cascade is three dimensional, so the splitting occurs in a direction orthogonal to both the flow direction and the initial combining and focusing, that is, up and down in the figure.
[0017] The two combined flows move separately from each other and are directed to be in lateral proximity at stage 22 . At stage 24 , the two separate combined flows are combined into a second combined flow, which is then focused at stage 26 . This combined flow is then split again at stage 28 in a similar or identical fashion as at stage 20 , separated at stage 30 and then recombined at stage 32 . At 34 , the combined flow is then focused. While this process may repeat as many times as desired, only limited by the ability of the materials to remain separated from each other with no complete mixing when combined, at some point the combined flow will exit the cascade as a single flow through an exit orifice or nozzle. An advantage of this technique lies in its ability to produce material features much smaller and more numerous than the fluidic channels that convey them.
[0018] FIG. 2 shows an embodiment of a cascade. A first material enters the cascade through channel 40 , and a second material enters the cascade through a channel 42 . Note that these channels, referred to as separating channels as they separate or maintain the separation between flows, may curve to one side or the other and change levels. The two flows are combined using a combining channel 44 . As discussed above, the combining channel has a focusing region 46 in which the combined flow is compressed or focused into a channel having a lateral extent approximately equal to the lateral extent of either of the individual separating channels 40 and 42 .
[0019] The combined flow is then split into two separate combined flows at the junction of the combining channel 46 and the splitter channels 50 and 48 . As shown in FIG. 2 , the splitter channels split the flows in a direction orthogonal to the direction of the combined flow in the combining channel 46 . In this example, the combined flow is split ‘up’ and ‘down’ relative to the combining channel 46 . The direction may not be fully orthogonal, but may be partially orthogonal, such as going upwards at an angle between straight up and straight ahead. Each combined flow in the splitting channels 50 and 48 consists of a stripe or finger of the first material and a stripe or finger of the second material. As mentioned above, the device is three dimensional and may be formed from layers.
[0020] The two separated combined flows are recombined into a second combined flow by combining channel 52 , which also focuses the second combined flow. The second combined flow in this example consists of four interleaved fingers, two each of the first and second materials. A second set of splitter channels, 56 and 54 then split the second combined flow into two separate combined flows. The structure 58 includes another combining channel, forming a third combined flow of 8 interleaved fingers, 4 each of the first and second materials. Optionally the structure 58 may also include an exit orifice with chamfered walls to allow the combined flow to exit the cascade as a single flow.
[0021] In operation, looking at FIG. 2 , a first material enters the cascade at layer +1 at 40 . The combining layer acts as the reference layer 0. A second material then enters the cascade at layer −1 42 . These two materials combine into combined flow at layer 0, in this case at Y structure 46 . Note that the combined flow consists of two stripes of material, one each of the first and second materials. Splitter channels 48 and 50 then separate the combined flow into two separate combined flows, each flowing into layers +1 and −1. The layers then recombine into a second combined flow at 52 . Note that the combined flow now has 4 stripes of material, 2 each of the first and second materials.
[0022] One should note that the structure of FIG. 2 may have abrupt transitions between the layers. This may result in dead volumes in the corners of the various transitions where the materials congregate in the corners initially and the remaining flow passes by the congregated material. However, over time, and with the device starting and stopping, the congregated material may harden or otherwise clog the exit orifices. In addition these abrupt transitions may induce flow irregularities which can lead to substantial or complete mixing of the materials in the stripes. It may then be desirable to have the flow ‘swept,’ meaning that the corners are angled or other wise machined, cut or formed, to eliminate the abrupt steps. This is discussed in co-pending application “Oblique Angle Micromachining of Fluidic Structures,” (Attorney Docket No. 20100587-US-NP-9841-0215).
[0023] The splitting and combining processes may continue as long as desired within the constraints of the fluids, which may be pastes, to maintain their individual compositions without complete mixing. At each stage of combining and focusing, the line count doubles and the width is decreased for each line by a factor of 2. The cumulative line width reduction is 2 n , which is the same for the number of lines. From a manufacturing standpoint, it is useful for the device to be assembled from layers fabricated separately and then stacked with an alignment tolerance. The layers are then clamped or bonded together. FIG. 3 shows an embodiment of such a device.
[0024] In this embodiment, the device consists of 9 layers. In this particular example, bolts, such as that would use bolt hole 63 , clamp the device together through corresponding holes on all of the layers. The two materials enter from opposite sides of the device. However, this is just an example and no limitation to any particular configuration is intended, nor should any be implied. Further, this particular example uses two materials and has 3 cascades repeated 25 times. These all consist of examples to aid in the understanding of the invention and no limitation to any particular configuration is intended nor should it be implied.
[0025] A first material enters the device through the sealing plate 63 and enters distribution manifold 61 and the second material enters through the opposite facing sealing plate 59 and enters distribution manifold 65 . Each manifold produces a substantially equalized source of fluid pressure to an array of cascades that will perform the fluid folding.
[0026] Optional layers 71 and 75 contain series of ports 60 and 70 , respectively. These layers provide one entry point for each of the cascades in the device, and may contribute to the equalization of the pressures of the materials entering the cascades. These layers may also be referred to as layers −2 and +2, in order to correspond to the layer reference used above.
[0027] On a first fluid folding layer 71 , the array of ports 70 conveys a first fluid from its distribution manifold to an array of separation channels 62 on a second fluid folding layer 81 . The first fluid is diverted laterally in a first direction on the second fluid folding layer. On a third fluid folding layer 75 , an array of ports 70 conveys a second fluid from its distribution manifold to an array of separation channels 72 on a fourth fluid folding layer 85 . On the fourth fluid folding layer 85 , the second fluid is diverted laterally in a second direction opposite the first direction.
[0028] The directions of the separation channels may be flexible. For convenience, in this embodiment all of the separation channels on a given layer all curve in the same direction. Looking at layer 81 , for example, the separation channels in arrays 62 , 64 and 66 all divert the flows laterally towards the right side of the drawing. These channels could go in different directions, or could all go to the left as well. The same holds true for the separating channels on layer 85 in arrays 72 , 74 and 76 .
[0029] On a fifth fluid folding layer 95 , flows from the second and fourth layers are combined and focused into a co-laminar flow by the combining channels in array 80 . The flows then split ‘vertically’ into two flows on the second and fourth folding layers through arrays 64 and 74 , respectively. A first combined flow is diverted laterally in the first direction on the second fluid folding layer using array 64 . The second combined flow is diverted laterally into an array of separation channels on the fourth fluid folding layer using array 74 .
[0030] The flows then return to the fifth fluid folding layer 95 , where they combine and focus into a second combined, co-laminar flow using array 82 . This process repeats n times, each time doubling the number of interdigitated stripes of materials. Downstream of the final stage of the splitting and separating, the flows from all of the cascades are optionally combined together to a common extrusion slot orifice. In the example provided, there are 3 repetitions of the process resulting in 8 interdigitated stripes from each cascade. There are 25 cascades, so the resulting flow will have 200 interdigitated stripes, 100 of each material.
[0031] One should note that while the device shown here has the materials arranged on opposite sides of the extruding orifice, the materials could be introduced on the same side of the orifice
[0032] This co-extrusion device of FIG. 3 can be configured and moved relative to a substrate to deliver the lines of material, as shown in FIG. 4 as device 104 . The substrate 102 would be positioned in close proximity to the applicator at a distance that is on the order of 10-1000 microns, referred to as the working distance. The substrate moves relative to the device at a speed comparable to the speed with which fluid exits from the printhead/applicator 106 . The co-extrusion device contains the fluid reservoirs as well as the printhead/applicator 106 , as well as control and power circuitry. Optionally the fluid reservoirs may be located remotely and fluids delivered to the device as needed through hoses or other plumbing.
[0033] In one embodiment, the printhead assembly is configured with components that are chamfered or cut away in such a manner, typically at 45 degrees, that the layered assembly may be held a close proximity to the substrate at a tilted angle. The tilt of the printhead assembly enables a feature that the paste exiting the fluid exit orifice forms an obtuse angle (between 90 and 180 degrees) with the deposited paste on the substrate. This reduces the bending strain on the extruded paste which can aid in the preservation of interdigitated feature fidelity, reduce mixing, and increase print speed.
[0034] A co-extrusion device such as that shown in FIGS. 2-4 may be used to form devices that benefit from tightly spaced interdigitated stripes of dissimilar materials including batteries, fuel cells, electrical interconnects and others. In the case of interconnects, vertically stacked integrated circuits may be interconnected along their edges with a series of metal lines separated by insulating spacers. In the case of electrochemical devices such as fuel cells and batteries, the interdigitated structures can enhance performance in a variety of ways. Air cathodes of metal air batteries could be structured to have interdigitated regions of hydrophilic and hydrophobic regions. This will typically exhibit improved oxygen reduction activity, improving the power output of the device.
[0035] FIG. 5 shows an example of such a device 110 . A hydrophobic membrane 114 has an electrode 112 residing on it. A separator 116 resides on the electrode 112 . The electrode in this example consists of interleaved fingers of porous, hydrophobic regions 118 and porous hydrophilic electro-catalyst regions 120 . As mentioned above, this can exhibit improved oxygen reduction activity and improve power output. Further, increasing the surface area of the three-phase boundary where the solid catalyst particle, liquid electrolyte and gas-phase reactant interact. For expensive catalysts such as platinum, such structures offer the potential of significant cost reduction.
[0036] FIGS. 6-10 show embodiments of interdigitated co-extrusion structures particularly useful to battery electrode formation. In FIG. 6 , the electrode 130 consists of two materials. A first material 132 is an electrode material, such as a cathode or anode active electrode. The material 134 is ionically conductive material, either through solid electrolyte conduction or through porosity. Alternatively, the regions of material 134 may be fugitive or sacrificial material removed during a later drying or firing stage in the manufacturing process. In FIG. 6 , the thinner, ionically conductive regions traverse the entire thickness of the electrode layer.
[0037] In one embodiment of the formation process for such a feature, the initial flows prior to folding may consist of two flows of material, one of 134 and one of 132 . Alternatively, there could be three flows prior to folding, one of material 134 surrounded by flows of 132 . This can be important if the two materials interact differently with the walls of the fluidic channels which otherwise could cause lack of symmetry in the combining, mixing and separation of the flows.
[0038] One should note that the deposition of the electrically conductive cathode or anode material and the second material onto the membrane result in a structure having interdigitated features of different materials in fluid form. Fluid, as that term is used here, means a gel, a paste, a slurry or a suspension. While these structures may progress through drying or firing stages, they will initially exist in a fluid form.
[0039] Further, at least one of these structures will generally have a high aspect ratio. As used here, the aspect ratio means the ratio of the maximum height to the maximum width of a structure or feature. Looking at FIG. 6 , one can see that the feature 134 in the interdigitated structure has a high aspect ratio, its height, running in the direction from the top of the page to the bottom, is much larger than its width, running from the left to right across the page. Generally, at least one of the features formed from one of the interdigitated materials will have an aspect ratio greater than 1 .
[0040] In an alternative embodiment, shown in FIG. 7 , the ionically conducting region does not traverse the full thickness of the electrode. This can be formed in two processes, first forming a blanket coat of cathode or anode material followed by an interdigitated coat of the ionically conducting region and the electrode material. A single-step approach would make use of poly-extrusion where the blanket electrode material would be introduced under the ionically conducting material by tailoring the timing of the introduction of the materials into the printhead.
[0041] One must note that the proportions of the materials differ greatly, with the cathode or anode material 132 having a much greater width than the ionically conductive material 134 . This may occur in many different ways. For example, the input channels, such as 42 and 40 from FIG. 2 , may have different sizes. Alternatively, the flow rate of material put into the channels could differ, with much more of the material 132 entering one of the channels than the material 134 .
[0042] In FIG. 8 , a third material is introduced through the printhead, in this case a principally electrically conducting material 140 , where the term ‘principally’ refers to the material having a higher expression of the relevant characteristic than the other materials. The manipulation of materials in the printhead and the subsequent folding processes can be controlled to allow these types of structures to be formed. For example, the three materials can be combined in a three way folding operation to form the central layer of the structure and two layer folding can be performed prior to and subsequent to the application of the central layer. This can be performed with three sequential applicators or unified in a single applicator which executes all three folding operations. In this embodiment it will be important to align the fluidic layers so that the features in FIG. 9 are continuous through the extruded structure.
[0043] FIG. 9 shows a structure similar to that of FIG. 7 , where the material 134 was a fugitive material, removed after printing leaving a gap such as 142 . FIG. 10 shows an embodiment similar to FIG. 8 , with the fugitive material removed leaving gaps 142 , and having the principally electrically conducting material 140 . These gaps could be subsequently filled with electrolyte material such as a liquid electrolyte to make substantially ionically conducting regions within the electrode structure.
[0044] These gaps could also subsequently be filled with the opposite of the cathode or anode material and a spacer material which prevents electrical contact of the anode and cathode materials but allows ionic transport between the electrodes, forming the opposing electrodes of an electrochemical cell such as a battery with alternating cathode and anode regions. Alternatively these gaps could be filled with a second electrode material and spacer material forming the opposing electrodes of an electrolytic capacitor or supercapacitor.
[0045] One alternative mentioned previously in the discussion involved flowing three materials. Referring back to FIG. 2 , one can see a possibility of altering the initial flow. Instead of having only two input channels 40 and 42 in to the combining channel 46 , one could have three or more input channels. An example of this is shown by combination channel 146 in FIG. 11 . In FIG. 11 , the combination channel has 3 input channels, allowing combination of 3 materials. From this point forward in the process, the remaining structure would be the same. Instead of folding two-material flows, however, the remaining structures would fold three-material flows. More than 3 input channels could also be used; this merely provides an example of more than 2 materials.
[0046] In this manner, interdigitated structures having micron features on a micron scale can be formed using a co-extrusion device. The co-extrusion device may take the form of a printhead, allowing faster formation of the structures using printing techniques.
[0047] It will be appreciated that several 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.
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A method for depositing a structure comprising interdigitated materials includes merging flows of at least two materials in a first direction into a first combined flow, dividing the first combined flow in a second direction to produce at least two separate flows, wherein the second direction is perpendicular to the first direction, and merging the two separate flows into a second combined flow.
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BACKGROUND OF THE INVENTION
This invention relates to a unique entry door system comprised of a plurality of uniquely constructed panels.
In the housing construction industry, entry doors are generally constructed of wooden frames with either a wooden door or a flush metal door. It is generally recognized that the wood door has a more beautiful aesthetic appearance. Attempts have been made to plant-on or add-on panels to the metal door to give it a better aesthetic appearance but to date, within our knowledge, there has been no completely satisfactory door developed in which a metal door is utilized to give the exceptional insulating qualities of such a door and at the same time produce the aesthetic appearance of a wood door.
Further, to our knowledge, no one has conceived of a panel construction using the insulating qualities of a metal panel with an insulating core that can be utilized for both a door panel and side panel and which gives the entire unit an aesthetic wood appearance.
Although a need has existed for versatile entrance systems from which a variety of styles, configurations, and miscellaneous options can be offered for a complete package, no such system has been devised.
SUMMARY OF THE INVENTION
In accordance with the present invention, we provide the unique construction for a decorative panel. This construction can be used for either the door or doors of a system or side panels mounted adjacent the door. This system permits providing a customer with a complete entry system including the door or doors and a side panel or side panels all encompassed within a frame so as to be shipped and sold as a complete entrance system.
The unique construction of the panels permits the use of the insulation advantages obtained by the use of a core-filled metal door while at the same time providing an authentic wooden look to the entire system be it just a single door, a door with one or two side panels or a combination of two doors with side panels. All of these panels are constructed of substantially the same components but of different size. The present invention permits the customer to order a system complete and ready to install. There is enough flexibility in the entire system to allow the customer to customize his system if he so chooses. For example, he can order a unit which includes a door with one side light, a door with side lights on each of the sides of the door or two doors with side lights on each of the doors. At the same time, the customer is assured of a beauty like that of an authentic wood door and wood side panels.
In accordance with this invention, the panels for both the door and the side panel are formed of metallic skin members secured at their side peripheral edges to stiles and at the top and bottom peripheral edges to rails. A polyurethane foam is injected into the space and formed in place so as to be bonded to the interior surfaces of the skin members and to the stiles and rails. This gives the panel exceptional insulating qualities.
The panel is given a wood-like appearance by securing to selected portions of the exterior surfaces of the skin members wood base panel elements. To these base panel elements is secured a raised panel element and wooden molding beads secured to the raised panel elements and the base panel elements along the peripheral edges of the raised panel elements.
Within a preferred embodiment of this invention, wooden stile facing pieces are secured to portions of the exterior surfaces of the skin member along adjacent and over the stile members and also over the rail members. This combination gives the door and side panels an authentic wood appearance so as to project the beauty of a wood door or doors and a side panel or panels.
Within the more specific preferred embodiment of this invention, a central portion of at least one of the exterior surfaces of the skin members is covered by a hardwood center rail which permits a design to be carved into the wood.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of an entrance system of this invention in which only the door is included.
FIG. 2 is a front elevational view of the door entrance system of this invention in which a door and one side light is included.
FIG. 3 is another embodiment of the entrance system of this invention in which a door and two side lights are included.
FIG. 4 is still another embodiment of this invention in which two doors and two side lights are included.
FIG. 5 is an elevational, cross-sectional view taken along the plane V--V of all of the FIGS. 1, 2 and 3.
FIG. 6 is a partial, enlarged cross-sectional view of a portion of FIG. 5 at the top of the door.
FIG. 7 is an elevational, cross-sectional view taken along the plane VII--VII of the side panel of FIGS. 2 and 3.
FIG. 8 is a cross-sectional view taken along the plane VIII--VIII of FIG. 1.
FIG. 9 is a cross-sectional view taken along the plane IX--IX of FIG. 3.
FIG. 10 is a cross-sectional view taken along the plane X--X of FIG. 3.
FIG. 11 is a partial, enlarged cross-sectional view of a right hand portion of FIG. 8.
FIG. 12 is an enlarged cross-sectional view of a portion of FIG. 8 illustrating the relationship of some of the wood base panel elements, the raised panel elements and the wooden molding beads.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, reference numerals 100, 200, 300 and 400 as disclosed in FIGS. 1, 2, 3 and 4, respectively, designate different entry systems constructed in accordance with the present invention. The entry system 100 of FIG. 1 includes only the door unit 1 with a frame 2. FIG. 2 discloses an entry system 200 which includes a door unit 1a of identical construction to the door unit 1 of FIG. 1 and a side panel or side light 101. The door 1a and side light 101 is framed by the frame 4. The entry unit 300 of FIG. 3 includes the door unit 1b, also identical to the door unit 1 of FIG. 1, and two side light units 101a and 101b identical to the side light unit 101 of FIG. 2. The side lights 101a, 101b and door unit 1b are framed by the frame 5. The entry system 400 of FIG. 4 includes the two door units 1c and 1d and the two side lights 101c and 101d. Door units 1c and 1d are identical to the door unit 1 of FIG. 1 and the side lights 101c and 101d are identical to the side light 101 of FIG. 2. The door units 1c and 1d and side lights 101c and 101d are framed by frame 6. In all of the entry systems the sill 7 is a treated wooden sill member 7a covered by an anodized sill cover 7b. Also the bottom edge of the door rail 21 is provided with a step which is contacted by the three-finned bottom sweep 8 to provide an excellent weather barrier.
As disclosed in FIG. 8 the frame 2 of entry system 100 includes the side door jambs 2a and 2b and top door jamb 2c. The entry system 200 includes the door jamb 4a and side light jamb 4b and top jamb 4c. The frame 5 for entry system 300 of FIG. 3 includes the side light jambs 5a and 5b and upper door jamb 50. In both systems 200 and 300 the door units are hinged to a side light by a hinge 3. (FIGS. 9 and 10). An astragal like that shown at 13 in FIG. 9 is located between the side light and door unit. In system 400 one or both of the door units can be hinged to a side light by hinges like that of hinge 3. The frame 6 of system 400 includes the side light jambs 6a and 6b and upper door jamb 6c. Specially designed recesses are provided at appropriate places in the jambs and astragals in which compression-type vinyl covered foam weather stripping elements identified as 35a (FIGS. 5 and 6), 35b (FIG. 7), 35c and 35d (FIGS. 8 and 11) and 35e and 35f (FIGS. 9 and 10) are located.
As will be described hereinafter, the side lights 101, 101a, 101b, 101c and 101d are of the same composition as the door units and are screwed (not shown) to the door frame through the sill, head and side jambs. An inactive sill stop 108 replaces the sweep 8.
Since the construction of all of the door units of FIGS. 1-4 are identical, the description of the doors for all of the entry systems 100, 200, 300 and 400 will be described in relation to the door unit 1 of FIG. 1. Similarly, since all of the side lights 101a, 101b, 101c and 101d of FIGS. 2-4 are identical to side light 101, a description of the side lights will be restricted to the description of the side light 101 of FIG. 2.
Referring now to FIGS. 5, 6, 8, 11 and 12, it will be observed that the door panel 1 is constructed of an inner metal skin member 11 and an outer metal skin member 12 spaced from each other. These metal skin members 11 and 12 are formed of a 24 gauge electro-galvanized steel. The vertical edges of the steel skin members are crimped at 14 and 15 along one edge and at 16 and 17 along the other edge (FIGS. 8 and 11). The crimped edges are inserted in grooves formed in the wood door stiles 18 and 19 and are also glued to the stiles with a contact cement sold under the trademark H. B. Fuller Maxbond 30. The top edges of the metal skin members 11 and 12 are also bonded to the top rail 20 and bottom rail 21 (FIGS. 5 and 6).
The space between the steel skin members 11 and 12, the stiles 18 and 19 and the rails 20 and 21 are injected with an isocyanate polyurethane foam 9 which is formed in place and permanently bonded to the steel skin members 11 and 12, the stiles 18 and 19 and the rails 20 and 21. This foam product is a Freeman Chemical, 30-2023, 150 cylinder, 30-1961 resin. The bonding of the polyurethane foam and the gluing of the wood door stiles and rails to the edges of the skin members 11 and 12 along with the connection of the crimped edges of the skin members to the stiles 18 and 19 prevents delamination and makes the core an integral part of the door system.
A raised wood panel effect is produced on the exterior faces of the skin members 11 and 12 by a unique arrangement of wood pieces glued onto each of the exterior surfaces of the inner and outer steel skin members 11 and 12.
The wood pieces on the outer skin member 12 include the stile wood facing pieces 22a (FIGS. 1 and 8) extending vertically along the edges of the door and covering the stiles 18 and 19 as well as a portion of the skin 12. The rail wood facing pieces 23a at both the top and bottom of the door cover the rails 20 and 21 and a portion of the skin 12. Between the wood facing pieces 22a and 23a is located the glass unit or window assembly 24 and raised panel assemblies 25. The glass unit 24 is of a conventional type and is fit into an opening cut in the core panel. If a glass unit is not preferred, other raised panel assemblies could be substituted for the glass unit, it being understood the opening would not then be provided.
The raised panel assemblies are a unique assembly which produces a design giving the door a raised panel effect. Each assembly (FIGS. 5, 8, 11 and 12) includes two base panels 26a with separate raised panels 27a glued thereto with a polyvinyl acetate Type I. The raised panels 27a are stapled from the back side to the base panel 26a before the base panel is glued on the skin 12. The combined thickness of base panel 26a and raised panel 27a is the same as the thickness of each of the pieces 22a and 23a. It will be noted in FIGS. 5 and 8 that the facing pieces 22a and 23a include recesses 28a and 29a respectively which receive base panels 26a so that the side facing pieces 22a and bottom facing pieces 23a slightly overlap the edges of the base panels 26a.
A vertically extending center piece 30a is located between the two raised panel assemblies 25a. Piece 30a is of the same thickness as pieces 22a and 23a and also includes the recess 31a for receiving the edges of the base panels 26a so as to overlap the same. Further, a center rail 32a (FIG. 5) extends laterally across the door between the two stile facing pieces 22a. It covers the space between the window assembly 24 and the raised panel assemblies 25a. It also is of the same thickness as pieces 22a and 22b and has a recess 33a receiving the top edges of and overlapping the base panels 26a. The center rail is a thick solid hardwood piece on which a decorative design 34 can be carved as disclosed in FIG. 3. A number of decorative wood beads or moldings 36a are secured to the various wood pieces as disclosed in the drawings to create a double picture frame look and also add greater strength at the joints between the separate parts.
The material from which the various wood pieces as above described are constructed is as follows. Base panels 26a are constructed from 3-ply wood, a hardwood veneer of vertical grain on each side of a wood core with a horizontal grain. The rough thickness is 0.129 inches but when sanded is finished to a thickness of 0.100 inches. The raised panels 27a are formed of a 5-ply wood product consisting of three plys of wood core covered on each side by a hardwood veneer of vertical grain. The original rough thickness of this 5-ply panel is 0.255 inches which is finished to a thickness of 0.250 inches. The 5-ply stile and rail facing pieces are constructed of three plys of wood covered on each side by a hardwood veneer which in the rough has a thickness of 0.366 inches and is finished to 0.350 inches thickness. The center piece 30a has the same construction as the stile and rail facing pieces.
All of the above wood facing pieces are permanently bonded to the outer skin member 12. This is accomplished by first assembling the raised panels to the base panels as above described. Each of the wood pieces are permanently bonded to the steel skin member 12 with an exterior glue. Obviously where the parts are to be stapled from the back, the stapling is accomplished before the part is glued to steel skin member 12.
So far the entire description has been related to the exterior surface of the door. The interior surface of the door has an identical construction. That is, it includes the inner wood stile facing pieces 22b, the inner wood rail facing pieces 23b, the raised panel assemblies 25b, the base panels 26b, the raised panels 27b, recesses 28b and 29b in the facing pieces 22b and 23b, center piece 30b, recesses 31b, center rail 32b with recesses 33b and the wood beads or molding 36b. It is not considered necessary to repeat a detailed description of such elements because of their identity to the elements on the exterior of the door.
FIGS. 7, 9 and 10 disclose in greater detail the side panel or side lights 101, 101a, 101b, 101c and 101d previously referred to. Since the construction of all of these side lights are the same, only one description of side light 101 will be made.
Referring to FIGS. 7 and 9, it will be noted that the side light 101 has substantially the same composition as the door unit 1, the primary difference being in the size. Thus, the side light 101 includes the core panel 110 having the inner steel skin member 111 and the outer steel skin member 112 both of which have crimped edges 114, 115, 116 and 117 which are connected to the stiles 118 and 119. (FIGS. 9 and 10) Skin members 111 and 112 are also connected to the rails 120 and 121. (FIG. 7) The space between the skin members 111 and 112, stiles 118 and 119 and rails 120 and 121 are filled with a foam 109 as described above in relation to the description of the door 1.
The side light includes a conventional type of window assembly 124 located between the wood stile facing pieces 122a and 122b as disclosed in FIGS. 10 and 2. Raised panel assembly 125a is located below the window assembly 124 on the exterior of the side light and raised panel assembly 125b is located below the window assembly 124 on the inside of the side light.
The raised panel assembly 125a includes the base panel 126a to which is secured the raised panel 127a. The vertical edges of the base panel 126a fit into the recesses 128a of the outer wood stile facing pieces 122a. The upper and lower edges of the base panels fit into the recess 129a of the rail facing piece 123a. A center rail 132a is provided to fill in the space between the raised panel assembly 125a and the window assembly 124a. It also has a recess 133a receiving the top edge of the base panel 126a. Wooden molding beads 136a are provided around the peripheries of base panel 126a and raised panel 127a as described above in the description of door unit 1.
It should be understood as previously described that the inside surface of the core panel 110 includes the same facing as that on the exterior surface just described. Accordingly, it includes the inner wood stile facing pieces 122b, the inner wood rail facing pieces 123b, the raised panel assembly 125b which includes the base panel 126b and raised panels 127b, the center rail 132b and the wood beads or moldings 136b all as previously described in relationship to the outer exterior of side light 101.
Method of Construction
Each of the two panels forming the door unit 1 and the side panel or side lights 101 are constructed by first providing two steel flat sheets of 24 gauge electro-galvanized steel skin of sufficient size to form the two skin members 11 and 12. Steel sheets are then sheared to the proper size. The two sheets are then rolled and crimped on the two sides to form the crimped edges 14, 15, 16 and 17. A wood frame is then constructed of the stiles 18 and 19 and rails 20 and 21. The stiles include slots for receiving the crimped edges 14, 15, 16 and 17. Two skin members 11 and 12 are then attached to the stiles by sliding the crimped edges into the slots provided in the stiles.
The above subassembly is then put into a press and the isocyanate polyurethane foam such as a Freeman Chemical, 30-2023, 150 cylinder, 30-1961 resin, is injected through an opening in the bottom rail 21 into the space between the skin members 11 and 12 and the stiles 18, 19 and rails 20 and 21.
When the resin is injected in the space, it expands and becomes permanently bonded to the interior surface of the steel skin members 11 and 12 and also the stiles 18 and 19 and rails 20 and 21. This prevents delamination and makes the core an integral part of the door unit. Each raised panel assembly is then constructed by providing a base panel 26a to which is secured the raised panel 27a by means of a polyvinyl acetate Type I exterior glue and stapling the raised panel 27a from the back side to the base panel 26a. The wood stile facing pieces 22a and 22b, the wood rail facing pieces 23a and 23b, the center pieces 30a and 30b and center rails 32a and 32b are all provided in the appropriate size and shape, each of such members including the recesses as described above to provide the overlapping type joints with the raised panel assembly. These joints are all glued with a polyvinyl acetate Type I exterior glue and stapled from the back side with two staples per joint. This wood facing construction is then permanently bonded to the steel insulated core panel 10 with an exterior glue. This is accomplished on both of the exterior surfaces of inner steel skin member 11 and outer steel skin member 12. The entire unit is then inserted in a press while the glue is setting. The edges of the unit are then trimmed to provide the specific width and length of the door unit. If the glass unit is to be provided, the opening for the glass unit is then cut out.
After the glue has set, the unit is removed from the press and sanded on both sides. The window assembly is then inserted and secured in place after which the moldings or beads 36a and 36b are caulked and stapled at the seams between the various parts to create a double picture frame look and add greater strength at the joints between the separate parts.
Having described the method of constructing and assembling the door unit 1, it should be understood that a substantially similar method is utilized for constructing and assembling the side panels or side light 101. Therefore it is not necessary to repeat the various steps as described above.
Having described the preferred embodiment of my invention, it should become evident that the purpose of it is to provide the customer with a complete entrance system. My invention provides for a variety of styles, configurations, trims and miscellaneous options. The customer is able to order a system complete and ready to install, be it a single door, a single door and a single side panel, a single door with a double side panel or a double door with a double side panel. In other words, this invention provides sufficient flexibility for the customer so as to allow him to customize his system if he so chooses. My invention provides for an entry system with an exceptional insulating quality while projecting the beauty of a wood door.
Although I have disclosed preferred embodiments of my invention, it should be understood that other embodiments and modifications thereof can be obtained utilizing my concepts without deviating from the real spirit of this invention. Therefore, my invention should be limited only as set forth in the following claims.
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An entry door system constructed of panels having a metal skin filled with insulating rigid foam core and having a unique wood facing and whereby the system has exceptional insulating qualities while projecting the beauty of a wood door. The system includes door and side panel components of substantially the same construction, except for the size, and provides for a versatile arrangement of panel components which in different selected combinations can be secured together into a single unit ready to be installed. The wood facing of the core filled panels includes wood stile and rail facing pieces and one or more raised panel subassemblies comprising a base panel to which is secured a raised panel with decorative wooden beads located at their perimeters which creates a wood picture frame look on the outer surfaces of the panels.
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[0001] This application is a continuation application of U.S. Ser. No. 11/809,579 filed on May 31, 2007, which is a divisional application of U.S. continuation-in-part patent application Ser. No. 10/245,441 filed Sep. 17, 2002, which claims priority to PCT No. PCT/EP01/03341, filed Mar. 21, 2001, and also claims the benefit of U.S. Patent Application No. 60/195,678, filed Apr. 7, 2000, and UK Application No. GB00/06753.8, filed Mar. 21, 2000. The entireties of all of these applications are hereby incorporated by reference herein.
[0002] The present invention relates to transgenic organisms, and methods for producing such organisms. In particular, the invention relates to transgenic organisms which comprise one or more insertions of a transposable element, or transposon. The transposon is preferably the Minos transposon.
[0003] Transposons are genetic elements which are capable of “jumping” or transposing from one position to another within the genome of a species. Transposons are widely distributed amongst animals, including insects.
[0004] The availability of genetic methodologies for functional genomic analysis is crucial for the study of gene function and genome organization of complex eukaryotes. Of the three “classical” model animals, the fly, the worm and the mouse, efficient transposon based insertion methodologies have been developed for D. melanogaster and for C. elegans . The introduction of P element mediated transgenesis and insertional mutagenesis in Drosophila (Spradling & Rubin, (1982) Science 218:341-347) transformed Drosophila genetics and formed the paradigm for developing equivalent methodologies in other eukaryotes. However, the P element has a very restricted host range, and therefore other elements have been employed in the past decade as vectors for gene transfer and/or mutagenesis in a variety of complex eukaryotes, including nematodes, plants, fish and a bird.
[0005] Minos is a transposable element derived from Drosophila (Franz and Savakis, (1991) 25 NAR 19:6646). It is described in U.S. Pat. No. 5,840,865, which is incorporated herein by reference in its entirety. The use of Minos to transform insects is described in the foregoing US patent.
[0006] Mariner is a transposon originally isolated from Drosophila , but since discovered in 30 several invertebrate and vertebrate species. The use of mariner to transform organisms is described in International patent application W099/09817.
[0007] Hermes is derived from the common housefly. Its use in creating transgenic insects is described in U.S. Pat. No. 5,614,398, incorporated herein by reference in its entirety.
[0008] PiggyBac is a transposon derived from the baculovirus host Trichplusia ni . Its use for germ-line transformation of Medfly has been described by Handler et al., (1998) PNAS (USA) 95:7520-5.
[0009] European Patent Application 0955364 (Savakis et al., the disclosure of which is incorporated herein by reference) describes the use of Minos to transform cells, plants and animals. The generation of transgenic mice comprising one or more Minos insertions is described.
[0010] International Patent Application W099/07871 describes the use of the Tc1 transposon from C. elegans for the transformation of C. elegans and a human cell line.
[0011] The use of Drosophila P elements in D. melanogaster for enhancer trapping and gene tagging has been described; see Wilson et al., (1989) Genes dev. 3:1301; Spradling et al., (1999) Genetics 153:135.
[0012] In the techniques described in the prior art, the use of the cognate transposase for inducing transposon jumping is acknowledged to be necessary. Transgenic animals, where described, have the transposase provided in cis or trans, for example by cotransformation with transposase genes.
SUMMARY OF THE INVENTION
[0013] We have now developed an improved protocol for the generation of transgenic animals using transposable elements as a genetic manipulation tool. In the improved protocol, the transposase function is provided by crossing of transgenic organisms in order to produce organisms containing both transposon and transposase in the required cells or tissues. The invention allows tissue-specific, regulatable transposition events to be used for genetic manipulation of organisms.
[0014] According to a first aspect of the invention, there is provided a method for generating a transgenic organism, comprising the steps of:
(a) providing a first transgenic organism, which organism comprises, within at least a portion of its tissues or cells, one or more copies of a transposon; (b) providing a second organism, which organism comprises, in the genome of at least a portion of its tissues or cells, a transposase or one or more copies of a gene encoding a transposase; and (c) crossing the organism so as to obtain transgenic progeny which comprise, in at least a portion of their tissues or cells, both the transposon and the transposase.
[0018] The invention comprises the crossing of two transgenic organisms, wherein one organism comprises, preferably as a result of transgenesis, one or more copies of a transposon; and the other organism comprises, preferably as a result of transgenesis, one or more copies of the cognate transposase. Any organism comprising heterologous or artificially rearranged genetic material is transgenic; it is preferred that a transgenic organism according to the invention is a eukaryotic organism.
[0019] As used herein, the term “transposon” refers to a genetic element that can “jump” or tranpose from one position to another within the genome of an organism. In order to be mobilized, a transposon requires intact inverted terminal repeat sequences and the presence of an active transposase. The inverted terminal repeat structures function in the recognition, excision and re-insertion of transposon sequences by a transposase. Transposases are generally encoded by the transposon sequences, but can also be supplied in trans. It is preferred herein that the transposase enzyme required for transposition is not encoded by the transposon sequence itself and is supplied in trans.
[0020] It is highly preferred that the transposon is Minos; and/or that the organism is a mammal.
[0021] As used herein, the term “transposase” refers to an enzyme that performs the excision and/or insertion activities necessary for the transposition of a transposon. A “cognate” transposase, as referred to herein, is any transposase which is effective to activate transposition of a given transposon, including excision of the transposon from a first integration site and/or integration of the transposon at a second integration site. Preferably, the cognate transposase is the transposase which is naturally associated with the transposon in its in vivo situation in nature. However, the invention also encompasses modified transposases, which may have advantageously improved activities within the scope of the invention.
[0022] The transposon may be a natural transposon. Preferably, it is a type-2 transposon, such as Minos. Most, advantageously, it is Minos. Alternative transposons include, but are not limited to mariner, Hermes and piggyBac, the sequences of which are known in the art (see, e.g., U.S. Pat. No. 5,840,865 (Minos), WO 99/09817 (mariner), U.S. Pat. No. 5,614,398 (Hermes) and Handler et al., 1998, Proc. Natl. Acad. Sci. U.S.A. 95: 7520-7525, each of which is incorporated herein by reference). As used herein, a transposon is a specific type of transposon, e.g., “a Minos transposon” if the transposon retains at least the sequences necessary for the excision and/or re-insertion by the cognate transposase enzyme as that term is defined herein.
[0023] The invention moreover relates to the use of modified transposons, the modification being the removal or disruption of transposase sequences or the incorporation of one or more heterologous coding sequences and/or expression control sequences. Such coding sequences can include selectable and/or unselectable marker genes, which permit the identification of transposons in the genome and cloning of the loci into which the transposons have been integrated. Suitable markers include fluorescent and/or luminescent polypeptides, such as GFP and derivatives thereof, luciferase, β-galactosidase, or chloramphenicol acetyl transferase (CAT).
[0024] As used herein, the term “heterologous” refers to genetic sequences that are from a species other than the organism or transposon of interest. As used herein, the term “homologous” refers to a genetic sequence that is normally carried by the organism or transposon of interest.
[0025] As used herein, the term “portion,” when used in reference to the tissues or cells of an organism, means at least one cell of the organism, up to and including all cells of the organism.
[0026] As used herein, the term “control sequences” refers to those nucleic acid sequences that mediate the transcription and/or translation of a given nucleic acid sequence. Control sequences include, for example, promoters (both basal and regulated, including, for example, tissue-specific or temporally-regulated promoters, or inducible promoters), enhancers, silencers and locus control regions.
[0027] As used herein in regard to the regulation of expression, a “signal” refers to a tissue-specific signal, a developmental signal, or an exogenous signal.
[0028] As used herein, the term “inducible expression system” refers to control sequences that permit the variable regulation of expression of an operably linked nucleic acid sequence by the manipulation of one or more parameters, including, for example, the presence, absence or relative amount of a drug.
[0029] As used herein, the term “tissue specific signals” refers to those biological signals that mediate the expression of a gene in a manner such that the gene is differentially expressed in at least one tissue of an organism, relative to other tissues of that organism. By “differentially expressed” is meant at least a statistically significant difference (p<0.05) in expression rate or steady state accumulation of the gene product in one tissue, relative to another. Biological signals include, for example the presence, absence, or regulating activity of agents or factors (intracellular or extracellular) involved in, for example, signal transduction, transcription, translation and RNA or protein processing, transport and stability.
[0030] The following is a non-exclusive list of tissue specific promoters and literature references containing the necessary sequences to achieve expression characteristic of those promoters in their respective tissues; the entire content of each of these literature references is incorporated herein by reference: Bowman et al., 1995 Proc. Natl. Acad. Sci. USA 92,12115-12119 describe a brain-specific transferrin promoter; the synapsin I promoter is neuron specific (Schoch et al., 1996 J. Biol. Chem. 271, 3317-3323); the necdin promoter is post-mitotic neuron specific (Uetsuki et al., 1996 J. Biol. Chem. 271, 918-924); the neurofilament light promoter is neuron specific (Charron et al., 1995′J. Biol. Chem. 270, 30604-30610); the acetylcholine receptor promoter is neuron specific (Wood et al., 1995 J. Biol. Chem. 270, 30933-30940); the potassium channel promoter is high-frequency firing neuron specific (Gan et al., 1996 J. Biol. Chem. 271, 5859-5865); the chromogranin A promoter is neuroendocrine cell specific (Wu et al., 1995 A. J. Clin. Invest. 96, 568-578); the Von Willebrand factor promoter is brain endothelium specific (Aird et al., 1995 Proc. Natl. Acad. Sci. USA 92, 4567-4571); the flt-1 promoter is endothelium specific (Morishita et al., 1995 J. Biol. Chem. 270, 27948-27953); the preproendothelin-1 promoter is endothelium, epithelium and muscle specific (Harats et al., 1995 J. Clin. Invest. 95, 1335-1344); the GLUT4 promoter is skeletal muscle specific (Olson and Pessin, 1995 J. Biol. Chem. 270, 23491-23495); the Slow/fast troponins promoter is slow/fast twitch myofibre specific (Corin et al., 1995 Proc. Natl. Acad. Sci. USA 92, 6185-6189); the α-Actin promoter is smooth muscle specific (Shimizu et al., 1995 J. Biol. Chem. 270, 7631-7643); the Myosin heavy chain promoter is smooth muscle specific (Kallmeier et al., 1995 J. Biol. Chem. 270, 30949-30957); the E-cadherin promoter is epithelium specific (Hennig et al., 1996 J. Biol. Chem. 271, 595-602); the cytokeratins promoter is keratinocyte specific (Alexander et al., 1995 B. Hum. Mol. Genet. 4, 993-999); the transglutaminase 3 promoter is keratinocyte specific (J. Lee et al., 1996 J. Biol. Chem. 271, 4561-4568); the bullous pemphigoid antigen promoter is basal keratinocyte specific (Tamai et al., 1995 J. Biol. Chem. 270, 7609-7614); the keratin 6 promoter is proliferating epidermis specific (Ramirez et al., 1995 Proc. Natl. Acad. Sci. USA 92, 4783-4787); the collagen α1 promoter is hepatic stellate cell and skin/tendon fibroblast specific (Houglum et al., 1995 J. Clin. Invest. 96, 2269-2276); the type X collagen promoter is hypertrophic chondrocyte specific (Long & Linsenmayer, 1995 Hum. Gene Ther. 6, 419-428); the Factor VII promoter is liver specific (Greenberg et al., 1995 Proc. Natl. Acad. Sci. USA 92, 12347-1235); the fatty acid synthase promoter is liver and adipose tissue specific (Soncini et al., 1995 J. Biol. Chem. 270, 30339-3034); the carbamoyl phosphate synthetase I promoter is portal vein hepatocyte and small intestine specific (Christoffels et al., 1995 J. Biol. Chem. 270, 24932-24940); the Na—K—Cl transporter promoter is kidney (loop of Henle) specific (Igarashi et al., 1996 J. Biol. Chem. 271, 9666-9674); the scavenger receptor A promoter is macrophages and foam cell specific (Horvai et al., 1995 Proc. Natl. Acad. Sci. USA 92, 5391-5395); the glycoprotein IIb promoter is megakaryocyte and platelet specific (Block & Poncz, 1995 Stem Cells 13, 135-145); the yc chain promoter is hematopoietic cell specific (Markiewicz et al., 1996 J. Biol. Chem. 271, 14849-14855); and the CD11b promoter is mature myeloid cell specific (Dziennis et al., 1995 Blood 85, 319-329).
[0031] As used herein, the term “developmental signals” refers to those biological signals that mediate the expression of a gene in a manner such that its expression pattern varies relative to the developmental state of the organism or tissue within an organism. An expression pattern “varies” if the expression of the gene or its RNA or polypeptide product undergoes a statistically significant difference (p<0.05) in expression over the course of development of the organism or tissue. Multiple developmentally-regulated promoters are known for a variety of species, notably in model organisms used for developmental studies, e.g., C. elegans, Drosophila, Xenopus , sea urchin, zebrafish, etc., but also in mammals. Non-limiting examples of developmentally-regulated promoters include those for β-globin, T cell receptors, surfactant protein A (SP-A), alphafetoprotein and albumin, among many others.
[0032] As used herein, the term “exogenous signals” refers to signals generated by the administration of an agent to the organism. “Exogenous signals” useful according to the invention generally modulate the expression of a drug-regulatable promoter. A number of suitable drug-regulatable promoters and corresponding regulatory drugs are known (see for example, Miller & Whelan, Hum. Gene Ther. 8, 803-815), and include, for example, promoters regulated by tetracycline (or tetracycline analogs that function to regulate tet-responsive promoters), glucocorticoid steroids, sex hormone steroids, metals (e.g., zinc), lipopolysaccharide (LPS), ecdysone and isopropylthiogalactoside (IPTG).
[0033] A tetracycline-responsive expression system was originally described by Gossen & Bujard (1992 Proc. Natl. Acad. Sci. USA 89, 5547-5551). In that system, the presence of tet represses expression of genes linked to the tet-responsive promoter (the so-called “tet-off” system). Subsequently, variants of the tet responsive system were developed in which a mutant form of the tet repressor protein binds to DNA in the presence, but not in the absence, of tetracycline or its analogues, resulting in positive regulation by tetracycline and its analogs (the so-called “tet-on” system; see, e.g., WO 96/01313, which is incorporated herein by reference). Tetracycline analogs can be any one of a number of compounds that are closely related to tetracycline and which bind to the tet repressor with a K a of at least about 10 6 /M.
[0034] As used herein, the term “locus control region” or “LCR” refers to a DNA sequence which confers high level expression on a group (two or more) of genes by conferring an open chromatin conformation on the chromosomal region comprising such genes. Locus control regions are often located between the genes regulated by the LCR and generally comprise one or more DNAse hypersensitive regions. Numerous LCRs are known in the art. Representative examples are described as follows. The human β-globin LCR is described in, for example, Grosveld et al., 1987, Cell 51: 975-985, Talbot et al., 1989, Nature 338: 352-355, Levings & Bungert, 2002, Eur. J. Biochem. 269: 1589-1599 (review), and GenBank Accession No. AF064190. As another example, an evolutionarily conserved LCR resides between 3.1 and 3.7 kb upstream of the human red visual pigment gene (Nathans et al., 1989, Science 245: 831-838; Wang et al., 1992, Neuron 9: 429-440). The 3′ IgH LCR is provided in GenBank Accession No. Y14406. The murine tyrosinase LCR is provided in GenBank Accession No. AF364302. The human CD2 gene LCR is described by Kaptein et al., 1998, Gene Ther. 5: 320-330. The murine T cell receptor a/Dad1 LCR is described by Ortiz et al., 2001, J. Immunol. 167: 3836-3845.
[0035] In an advantageous embodiment, the transposase may be expressed in the transgenic organisms in a regulatable manner. This means that the activation of the transposon can be determined according to any desired criteria. For example, the transposase may be placed under the control of tissue-specific sequences, such that it is only expressed at desired locations in the transgenic organism. Such sequences may, for example, comprise tissue-specific promoters, enhancers and/or locus control sequences.
[0036] Moreover, the transposase may be placed under the control of one or more sequences which confer developmentally-regulated expression. This will result in the transposons being activated at a given stage in the development of the transgenic animal or its progeny.
[0037] Using the techniques of the invention, gene modification events can be observed at a very high frequency, due to the efficiency of mobilisation and insertion of transposons. Moreover, the locus of the modification may be identified precisely by locating the transposon insertion. Sequencing of flanking regions allows identification of the locus in databases, potentially without the need to sequence the locus. Moreover, the use of transposons provides a reversible mutagenesis strategy, such that modifications can be reversed in a controlled manner.
[0038] As used herein, the term “genetically manipulate” refers to a process that artificially alters the genetic makeup of an organism. The transposon-mediated excision or insertion of a transgene sequence as described herein is one example of genetic manipulation.
[0039] The transposon may be inserted into a gene. Preferably, the transposon is inserted into a highly transcribed gene, resulting in the localisation of said transposon in open chromatin. This increases the accessibility of the transposon which may result in increased transposition frequencies.
[0040] As used herein, the term “open chromatin” refers to a region of chromatin that is at least 10-fold more sensitive to the action of an endonucleoase, e.g., DNAse I, than surrounding regions. Because opening of the chromatin is a prerequisite to transcription activity, DNAse I sensitivity provides a measure of the transcriptional potentiation of a chromatin region; greater DNAse sensitivity generally corresponds to greater transcription activity. DNAse hypersensitivity assays are described by Weintraub & Groudine, 1976, Science 193: 848-856, incorporated herein by reference. “Highly transcribed” or “highly expressed” regions or genes are regions of open chromatin structure (i.e., at least 10-fold more DNAse I sensitive) that are transcribed and are preferably more than 10-fold more sensitive to DNAse I cleavage, e.g., preferably at least 20-fold or more, preferably 50-fold or 100 fold or more sensitive, than surrounding regions.
[0041] Moreover, the transposon may itself comprise, between the transposon ends, a highly-transcribed gene. This will cause activation of the chromatin structure into which the transposon integrates, facilitating access of the transposase thereto.
[0042] The transposon may be inserted into the gene by recombination. Furthermore, the transposon may be inserted into the gene by recombination in cells such as ES cells.
[0043] According to a second aspect of the invention, there is provided a method for detecting and characterising a genetic mutation in a transgenic organism, comprising the steps of:
(a) generating a transgenic organism by a procedure according to the first aspect of the invention; (b) characterising the phenotype of the transgenic organism; (c) detecting the position of one or more transposon insertion events in the genome of the organism; and (d) correlating the position of the insertion events with the observed phenotype, the position of the insertion events being indicative of the location of one or more gene loci connected with the observed phenotype.
[0048] As used herein, the term “reversion of gene disruptions” refers to the restoration of the expression of a polypeptide that was disrupted by the prior insertion of a transposon, which restoration follows the excision of the inserted transposon by a transposase. By “restoration” is meant that, following reversion, the expressed polypeptide is more abundant (i.e., at least 5% more abundant) or has greater activity (i.e., at least 5% greater activity) than prior to the reversion event.
[0049] As used herein, the term “characterize the phenotype” refers to the measurement of one or more parameters that determines the phenotype of an organism made transgenic by the transposon-mediated methods disclosed herein, relative to that parameter in a reference organism that is not made transgenic according to the transposon-mediated methods described herein. Non-limiting examples of phenotypic parameters include the measurement of the presence, absence, amount or activity of a polypeptide or one or more products of a reaction requiring or catalyzed by that polypeptide.
[0050] As used herein, the term “correlating the position of the insertion events with the observed phenotype” means determining the location of transposon insertion events in transgenic organisms according to the invention that exhibit a particular observed phenotype. Determining the location or detecting the position of an insertion can be performed on the chromosomal level, e.g., by fluorescence in situ hybridization, or, preferably, at the level of determining the sequence of those genomic regions flanking the insertion site. The observed phenotype can be, for example, activation or reversion of expression of a polypeptide or, alternatively, inactivation of the expression of a polypeptide.
[0051] The generation of genetic mutations in transgenic organisms as a result of transposon insertion after crossing of transgenic organisms according to the invention gives rise to novel phenotypic variations in the organisms, which can be traced back to insertion events in the genome of the organism. Transposon excisions characteristically result in the insertion of a small number of nucleotides into the host genome, left behind by the transposon and the recombination events associated with its insertion and subsequent excision. Small insertions may have small phenotypic effects, for example resulting from the insertion of a few amino acids into the sequence of a polypeptide. Alternatively, the effects may be more pronounced, possibly including the complete inactivation of a gene.
[0052] Transposon insertions are more likely to have significant phenotypic consequences, on the grounds that the insertion is much larger.
[0053] If a transposon is inserted into an intron of a gene, resulting in inactivation of the gene, its excision leads, in the majority of cases, to restoration of gene activity. Thus, the invention provides a reversible mutagenesis procedure, in which a gene can be inactivated and subsequently restored.
[0054] Insertion events may be detected by screening for the presence of the transposon, by probing for the nucleic acid sequence of the transposon. Excisions may also be identified by the “signature” sequence left behind upon excision.
[0055] In a preferred embodiment, transposons may be used to upregulate the expression of genes. For example, a transposon may be modified to include an enhancer or other transcriptional activation element. Mobilisation and insertion of such a transposon in the vicinity of a gene upregulates expression of the gene or gene locus. This embodiment has particular advantage in the isolation of oncogenes, which may be identified in clonal tumours by localisation of the transposon.
[0056] According to a third aspect, there is provided a method for isolating a gene which is correlated with a phenotypic characteristic in a transgenic animal, comprising the steps of:
(a) generating a transgenic organism by a procedure according to the first aspect of the invention; (b) characterising the phenotype of the transgenic organism; (c) detecting the position of one or more transposon insertion events in the genome of the organism; and (d) cloning the genetic loci comprising the insertions.
[0061] The invention provides clear advantages in functional genomics, since gene disruption or activation by transposon jumping is easily traced due to tagging by the transposon.
[0062] According to a fourth aspect, there is provided a method for isolating an enhancer in a transgenic animal, comprising the steps of:
(a) generating a transgenic organism by a procedure according to the first aspect of the invention, wherein the transposon comprises a reporter gene under the control of a minimal promoter such that it is expressed at a basal level; (b) assessing the level of expression of the reporter gene in one or more tissues of the transgenic organism; (c) identifying and cloning genetic loci in which the modulation of the reporter gene is increased or decreased compared to the basal expression level; and (d) characterising the cloned genetic loci.
[0067] According to a fifth aspect, there is provided a method for isolating an exon of an endogenous gene in a transgenic animal, comprising the steps of:
(a) generating a transgenic organism by a procedure according to the first aspect of the invention, wherein the transposon comprises a reporter gene which lacks translation initiation sequences but includes splice acceptor sequences; (b) identifying tissues of the organism in which the reporter gene is expressed; and (c) cloning the genetic loci comprising the expressed reporter gene.
[0071] As used herein, the term “lacks translation initiation sequences” means that the reporter gene does not have an in frame ATG codon within a Kozak consensus sequence (described in Kozak, 1986, Cell 44: 283, and refined in Kozak, 1987, J. Mol. Biol. 196: 947, Kozak, 1987, Nucl. Acids Res. 15: 8125 and Kozak, 1989, J. Cell Biol. 108: 229). A gene that lacks translation initiation sequences will not be expressed unless it is provided with such sequences, e.g., by insertion mutagenesis.
[0072] As used herein, the term “includes splice acceptor sequences” means that the reporter gene coding sequence in the transposon is preceded by a branch site consensus sequence (UCPuAPy), 20 to 50 nucleotides 5′ of a 3′ splice acceptor sequence AG/G (where the 3′ G is the splice acceptor).
[0073] The invention may be used to provided in vivo enhancer trap and exon trap functions, by inserting transposons which comprise marker genes which are modulated in their expression levels by the proximity with enhancers or exons. Suitable constructs for such applications are described in EP 0955364 and known in the art. Since transposon activation may be effected in a tissue-specific or developmentally regulated manner, the invention permits the trapping of enhancers and/or exons which are subject to similar regulation in the transgenic organism.
[0074] As used herein the term “enhancer” refers to a eukaryotic promoter sequence element that increases transcriptional efficiency in a manner that is relatively independent of position and orientation with respect to a nearby gene (see, e.g., Khoury and Gruss, 1983, Cell 33:313-314). The term “relatively independent” as used in the preceding sentence means independent of position and orientation effects relative to basal promoter elements, which generally have strict position and/or orientation requirements for proper promoter function. The ability of enhancer sequences to function upstream from, within or downstream from eukaryotic genes distinguishes them from basal promoter elements.
[0075] As used herein, the term “minimal promoter” refers to the minimal expression control element that is capable of initiating transcription of a selected DNA sequence to which it is operably linked. A minimal promoter frequently consists of a TATA box or TATA-like box but can include an initiator element (see, e.g., Smale & Baltimore, 1989, Cell 57: 103) containing a transcriptional initiation site located about 20-50 bases downstream of the TATA box. Generally, no additional upstream elements are present in a minimal promoter. Numerous minimal promoter sequences are known in the art.
[0076] As used herein, the term “basal level,” when used in reference to gene expression, means that level of expression that occurs from a minimal promoter.
[0077] As used herein, the terms “increased”, “decreased”, or “modulated” mean at least a 5% change in the entity being measured, relative to a reference. For example, reporter gene expression is increased if it is at least 5% higher under a given set of circumstances relative to a different set of circumstances, e.g., the presence, versus the absence of a stimulus.
[0078] As used herein, the term “characterizing the cloned genetic loci” refers to determining one or more parameters with regard to the cloned loci, including, for example, nucleic acid sequence, amino acid sequence of open reading frames, or similarity of either of these parameters to that of a known genetic locus.
[0079] According to a sixth aspect, there is provided a method for modulating the expression of a gene in an organism, comprising the steps of:
(a) generating a library of transgenic organisms according to the first aspect of the invention; and (b) selecting from said library one or more transgenic organisms in which the expression of a gene of interest is modulated as a result of one or more transposon insertion events.
[0082] As used herein, the term “library” refers to a plurality of transgenic organisms made using a transposon-mediated transgenesis method as disclosed herein. Generally, a library comprises members that while similar in most aspects, differ in one or more other aspects from other members of the library. Thus, a library of transgenic organisms would generally be all of the same species and all contain the same or related transposon or transposase, yet differ in sequences within the transposon sequence from member to member.
[0083] The invention moreover comprises transgenic animals suitable for crossing in a method according to the invention, and thus encompasses a transgenic organism comprising one or more copies of a heterologous transposon, said transgenic organism being free of nucleic acid sequences encoding the cognate transposase enzyme, and a transgenic organism encoding a transposase enzyme, said transgenic organism being free of the cognate transposon.
[0084] As used herein, the term “free of nucleic acid sequences encoding the cognate transposase enzyme” means that the transgenic organism does not encode a functional cognate transposase enzyme in its genome. A “functional” transposase enzyme is capable of performing excision and/or insertion of its cognate transposon sequence.
[0085] As used herein, “free of the cognate transposon” means that the transgenic organism does not encode in its genome a transoposon sequence that can be either excised and/or re-inserted by the cognate transposase.
DESCRIPTION OF THE FIGURES
[0086] FIG. 1 . Minos derived vectors. Minos inverted terminal repeats are shown as thick black arrows. White blocks outside these arrows indicate the sequences flanking the original Minos element in the D. hydei genome. Arrowheads indicate the positions of primers used to detect Minos excisions. Small arrows indicate the direction of transcription of the GFP and transposase genes. Black bars represent fragments used as probes.
[0087] FIG. 2 . Tissue specific expression of Minos transposase in transgenic mice. Northern blot analysis of thymus, spleen and kidney RNA isolated from TM2/+ mice (40-hr exposure). Control RNA is from thymus of a non-transgenic mouse. The lower panel shows the signal obtained upon re-hybridisation of the same filter with a mouse actin probe (3-br exposure).
[0088] FIG. 3 . Transposase dependent, tissue-specific excision of a Minos transposon in mice. Oligonucleotide primers flanking the transposon were used for PCR and the products were analysed by agarose gel electrophoresis. Left panel: Transposase-dependent excision in the thymus. Template DNA used: Lane 1, non transgenic; lane 2, TM2/+; lanes 3-7, MCG/+; lanes 8-12, MCG/+TM2/+. Right panel: Excision in various tissues of transposase-expressing mice. Template DNA used: Lanes 1, 3, 5, 7, 9, 11, from MCG/+ mice. Lanes 2, 4, 6, 8, 10, 12, from MCG/+TM2/+ mice. Lanes 1-2, thymus. Lanes 3-4, spleen. Lanes 5-6, liver. Lanes 7-8, kidney. Lanes 9-10, brain. Lanes 11-12, muscle. Lane 13, no DNA added.
[0089] FIG. 4 . Footprints left behind at chromosomal sites after Minos excision. DNA is extracted from thymus and spleen of a double transgenic mouse (top), or from an embryonic fibroblast cell line from a MCG/+ mouse after transfection with a transposase-expressing plasmid (bottom) and used as template for PCR with the flanking primers. PCR-amplified bands were cloned and 32 clones (19 from thymus and spleen and 13 from fibroblast cells) were sequenced. TA is the target site duplication. Nucleotides in red correspond to the ends of the transposon terminal repeats; nucleotides in blue are of unknown origin. The flanking nucleotides and TA repeats are aligned.
[0090] FIG. 5 . FISH analysis of Minos transpositions in thymus and spleen. Chromosomes were stained with DAPI Panels A and B are from the same MCG/+ metaphase nucleus, probed with a GFP and a telomere 14 specific probe, respectively. Panels C to F are nuclei probed with GFP. Panels C and D are from thymus and spleen respectively from the same MCG/+, TM2/+ mouse. Panels E and F are from spleen of two different MCG/+, TM2/+ mice. Yellow arrowheads indicate the original integration site of the transposon transgene, near the telomere of chromosome 14. Green arrowheads indicate the telomeres of chromosome 14. Red arrowheads indicate transposition events.
DETAILED DESCRIPTION OF THE INVENTION
[0091] Although in general the techniques mentioned herein are well known in the art, reference may be made in particular to Sambrook et al., Molecular Cloning, A Laboratory Manual (1989) and Ausubel et al., Short Protocols in Molecular Biology (1999) 4 th Ed, John Wiley & Sons, Inc.
[0092] A transgenic organism of the invention is preferably a multicellular eukaryotic organism, such as an animal, a plant or a fungus.
[0093] The organism is preferably an animal, more preferably a mammal. Advantageously, the organism is not an insect. Preferably, the organism is not D. melanogaster.
[0094] In a preferred embodiment, the organism is a plant.
[0095] Animals include animals of the phyla cnidaria, ctenophora, platyhelminthes, nematoda, annelida, mollusca, chelicerata, uniramia, crustacea and chordata. Uniramians include the subphylum hexapoda that includes insects such as the winged insects. Chordates include vertebrate groups such as mammals, birds, reptiles and amphibians. Particular examples of mammals include non-human primates, cats, dogs, ungulates such as cows, goats, pigs, sheep and horses and rodents such as mice, rats, gerbils and hamsters.
[0096] Plants include the seed-bearing plants angiosperms and conifers. Angiosperms include dicotyledons and monocotyledons. Examples of dicotyledonous plants include tobacco, ( Nicotiana plumbaginifolia and Nicotiana tabacum ), arabidopsis ( Arabidopsis thaliana ), Brassica napus, Brassica nigra, Datura innoxia, Vicia narbonensis, Vicia faba , pea ( Pisum sativum ), cauliflower, carnation and lentil ( Lens culinaris ). Examples of monocotyledonous plants include cereals such as wheat, barley, oats and maize.
Production of Transgenic Animals
[0097] Techniques for producing transgenic animals are well known in the art. A useful general textbook on this subject is Houdebine, Transgenic animals—Generation and Use (Harwood Academic, 1997)—an extensive review of the techniques used to generate transgenic animals from fish to mice and cows.
[0098] Advances in technologies for embryo micromanipulation now permit introduction of heterologous DNA into, for example, fertilised mammalian ova. For instance, totipotent or pluripotent stem cells can be transformed by microinjection, calcium phosphate mediated precipitation, liposome fusion, retroviral infection or other means, the transformed cells are then introduced into the embryo, and the embryo then develops into a transgenic animal. In a highly preferred method, developing embryos are infected with a retrovirus containing the desired DNA, and transgenic animals produced from the infected embryo. In a most preferred method, however, the appropriate DNAs are coinjected into the pronucleus or cytoplasm of embryos, preferably at the single cell stage, and the embryos allowed to develop into mature transgenic animals. Those techniques are well known. See reviews of standard laboratory procedures for microinjection of heterologous DNAs into mammalian fertilised ova, including Hogan et al., Manipulating the Mouse Embryo, (Cold Spring Harbor Press 1986); Krimpenfort et al., (1991) Bio/Technology 9:844; Palmiter et al., (1985) Cell 41:343; Kraemer et al., Genetic manipulation of the Mammalian Embryo, (Cold Spring Harbor Laboratory Press 1985); Hammer et al., (1985) Nature 315:680; Wagner et al., U.S. Pat. No. 5,175,385; Krimpenfort et al., U.S. Pat. No. 5,175,384, the respective contents of which are incorporated herein by reference.
[0099] Another method used to produce a transgenic animal involves microinjecting a nucleic acid into pro-nuclear stage eggs by standard methods. Injected eggs are then cultured before transfer into the oviducts of pseudopregnant recipients.
[0100] Transgenic animals may also be produced by nuclear transfer technology as described in Schnieke, A. E. et al., (1997) Science 278:2130 and Cibelli, J. B. et al., (1998) Science 280:1256. Using this method, fibroblasts from donor animals are stably transfected with a plasmid incorporating the coding sequences for a polypeptide of interest under the control of regulatory sequences. Stable transfectants are then fused to enucleated oocytes, cultured and transferred into female recipients.
[0101] Analysis of animals which may contain transgenic sequences would typically be performed by either PCR or Southern blot analysis following standard methods.
[0102] By way of a specific example for the construction of transgenic mammals, such as cows, nucleotide constructs comprising a sequence encoding a DNA binding molecule are microinjected using, for example, the technique described in U.S. Pat. No. 4,873,191, into oocytes which are obtained from ovaries freshly removed from the mammal. The oocytes are aspirated from the follicles and allowed to settle before fertilisation with thawed frozen sperm capacitated with heparin and prefractionated by Percoll gradient to isolate the motile fraction.
[0103] The fertilised oocytes are centrifuged, for example, for eight minutes at 15,000 g to visualise the pronuclei for injection and then cultured from the zygote to morula or blastocyst stage in oviduct tissue-conditioned medium. This medium is prepared by using luminal tissues scraped from oviducts and diluted in culture medium. The zygotes must be placed in the culture medium within two hours following microinjection.
[0104] Oestrous is then synchronized in the intended recipient mammals, such as cattle, by 30 administering coprostanol. Oestrous is produced within two days and the embryos are transferred to the recipients 5-7 days after oestrous. Successful transfer can be evaluated in the offspring by Southern blot.
[0105] Alternatively, the desired constructs can be introduced into embryonic stem cells (ES cells) and the cells cultured to ensure modification by the transgene. The modified cells are then injected into the blastula embryonic stage and the blastulas replaced into pseudopregnant hosts. The resulting offspring are chimeric with respect to the ES and host cells, and nonchimeric strains which exclusively comprise the ES progeny can be obtained using conventional cross-breeding. This technique is described, for example, in WO91/10741.
Production of Transgenic Plants
[0106] Techniques for producing transgenic plants are well known in the art. Typically, either whole plants, cells or protoplasts may be transformed with a suitable nucleic acid construct encoding a DNA binding molecule or target DNA (see above for examples of nucleic acid constructs). There are many methods for introducing transforming DNA constructs into cells, but not all are suitable for delivering DNA to plant cells. Suitable methods include Agrobacterium infection (see, among others, Turpen et al., (1993) J. Virol. Methods 42:227-239) or direct delivery of DNA such as, for example, by PEG-mediated transformation, by electroporation or by acceleration of DNA coated particles. Acceleration methods are generally preferred and include, for example, microprojectile bombardment. A typical protocol for producing transgenic plants (in particular monocotyledons), taken from U.S. Pat. No. 5,874,265, is described below.
[0107] An example of a method for delivering transforming DNA segments to plant cells is microprojectile bombardment. In this method, non-biological particles may be coated with nucleic acids and delivered into cells by a propelling force. Exemplary particles include those comprised of tungsten, gold, platinum, and the like.
[0108] A particular advantage of microprojectile bombardment, in addition to it being an effective means of reproducibly stably transforming both dicotyledons and monocotyledons, is that neither the isolation of protoplasts nor the susceptibility to Agrobacterium infection is required. An illustrative embodiment of a method for delivering DNA into plant cells by acceleration is a Biolistics Particle Delivery System, which can be used to propel particles coated with DNA through a screen, such as a stainless steel or Nytex screen, onto a filter surface covered with plant cells cultured in suspension. The screen disperses the tungsten-DNA particles so that they are not delivered to the recipient cells in large aggregates. It is believed that without a screen intervening between the projectile apparatus and the cells to be bombarded, the projectiles aggregate and may be too large for attaining a high frequency of transformation. This may be due to damage inflicted on the recipient cells by projectiles that are too large.
[0109] For the bombardment, cells in suspension are preferably concentrated on filters. Filters containing the cells to be bombarded are positioned at an appropriate distance below the microprojectile stopping plate. If desired, one or more screens are also positioned between the gun and the cells to be bombarded. Through the use of techniques set forth herein one may obtain up to 1000 or more clusters of cells transiently expressing a marker gene (“foci”) on the bombarded filter. The number of cells in a focus which express the exogenous gene product 48 hours post-bombardment often range from 1 to 10 and average 2 to 3.
[0110] After effecting delivery of exogenous DNA to recipient cells by any of the methods discussed above, a preferred step is to identify the transformed cells for further culturing and plant regeneration. This step may include assaying cultures directly for a screenable trait or by exposing the bombarded cultures to a selective agent or agents.
[0111] An example of a screenable marker trait is the red pigment produced, under the control of the R-locus in maize. This pigment may be detected by culturing cells on a solid support containing nutrient media capable of supporting growth at this stage, incubating the cells at, e.g., 18° C. and greater than 180 μE m −2 s −1 , and selecting cells from colonies (visible aggregates of cells) that are pigmented. These cells may be cultured further, either in suspension or on solid media.
[0112] An exemplary embodiment of methods for identifying transformed cells involves 30 exposing the bombarded cultures to a selective agent, such as a metabolic inhibitor, an antibiotic, herbicide or the like. Cells which have been transformed and have stably integrated a marker gene conferring resistance to the selective agent used, will grow and divide in culture. Sensitive cells will not be amenable to further culturing.
[0113] To use the bar-bialaphos selective system, bombarded cells on filters are resuspended in nonselective liquid medium, cultured (e.g. for one to two weeks) and transferred to filters overlaying solid medium containing from 1-3 mg/l bialaphos. While ranges of 1-3 mg/l will typically be preferred, it is proposed that ranges of 0.1-50 mg/l will find utility in the practice of the invention. The type of filter for use in bombardment is not believed to be particularly crucial, and can comprise any solid, porous, inert support.
[0114] Cells that survive the exposure to the selective agent may be cultured in media that supports regeneration of plants. Tissue is maintained on a basic media with hormones for about 2-4 weeks, then transferred to media with no hormones. After 2-4 weeks, shoot development will signal the time to transfer to another media.
[0115] Regeneration typically requires a progression of media whose composition has been 15 modified to provide the appropriate nutrients and hormonal signals during sequential developmental stages from the transformed callus to the more mature plant. Developing plantlets are transferred to soil, and hardened, e.g., in an environmentally controlled chamber at about 85% relative humidity, 600 ppm CO 2 , and 250 μE m −2 s −1 of light. Plants are preferably matured either in a growth chamber or greenhouse. Regeneration will typically take about 3-12 weeks. During regeneration, cells are grown on solid media in tissue culture vessels. An illustrative embodiment of such a vessel is a petri dish. Regenerating plants are preferably grown at about 19° C. to 28° C. After the regenerating plants have reached the stage of shoot and root development, they may be transferred to a greenhouse for further growth and testing.
[0116] Genomic DNA may be isolated from callus cell lines and plants to determine the presence of the exogenous gene through the use of techniques well known to those skilled in the art such as PCR and/or Southern blotting.
[0117] Several techniques exist for inserting the genetic information, the two main principles being direct introduction of the genetic information and introduction of the genetic information by use of a vector system. A review of the general techniques may be found in articles by Potrykus, (Annu. Rev. Plant Physiol. Plant Mol. Biol. [1991] 42:205-225) and Christou, (Agro-Food-Industry Hi-Tech March/April 1994 17-27).
[0118] The vector system used may comprise one vector, but it can comprise at least two vectors. In the case of two vectors, the vector system is normally referred to as a binary vector system. Binary vector systems are described in further detail in Gynheung An et al., (1980) Binary Vectors, Plant Molecular Biology Manual A 3, 1-19.
[0119] One extensively employed system for transformation of plant cells with a given promoter or nucleotide sequence or construct is based on the use of a Ti plasmid from Agrobacterium tumefaciens or a Ri plasmid from Agrobacterium rhizogenes (An et al., (1986) Plant Physiol. 81:301-305 and Butcher D. N. et al., (1980) Tissue Culture Methods for Plant Pathologists , eds.: D. S. Ingrains and J. P. Helgeson, 203-208).
[0120] Several different Ti and Ri plasmids have been constructed which are suitable for the construction of the plant or plant cell constructs described above.
Transposons
[0121] Minos transposons, and their cognate transposase, are described in detail in U.S. Pat. No. 5,840,865 and European patent application EP 0955364, the disclosures of which are incorporated herein by reference. Minos transposons may be modified, for instance to insert one or more selectable marker genes for example as referred to herein, according to general techniques. Specific techniques for modifying Minos are set forth in EP 0955364.
Marker Genes
[0122] Preferred marker genes include genes which encode fluorescent polypeptides. For 30 example, green fluorescent proteins (“GFPs”) of cnidarians, which act as their energy-transfer acceptors in bioluminescence, can be used in the invention. A green fluorescent protein, as used herein, is a protein that fluoresces green light, and a blue fluorescent protein is a protein that fluoresces blue light. GFPs have been isolated from the Pacific Northwest jellyfish, Aequorea victoria , from the sea pansy, Renilla reniformis , and from Phialidium gregarium . (Ward et al., (1982) Photochem. Photobiol., 35:803-808; Levine et al., (1982) Comp. Biochem. Physiol., 72B:77-85). See also Matz, et al., 1999, ibid for fluorescent proteins isolated recently from Anthoza species (accession nos. AF168419, AF168420, AF168421, AF168422, AF168423 and AF168424).
[0123] A variety of Aequorea -related GFPs having useful excitation and emission spectra have been engineered by modifying the amino acid sequence of a naturally occurring GFP from Aequorea victoria (Prasher et al., (1992) Gene 111:229-233; Heim et al., (1994) Proc. Natl. Acad. Sci. U.S.A., 91:12501-12504; PCT/US95/14692). As used herein, a fluorescent protein is an Aequorea -related fluorescent protein if any contiguous sequence of 150 amino acids of the fluorescent protein has at least 85% sequence identity with an amino acid sequence, either contiguous or non-contiguous, from the wild-type Aequorea green fluorescent protein (SwissProt Accession No. P42212). More preferably, a fluorescent protein is an Aequorea -related fluorescent protein if any contiguous sequence of 200 amino acids of the fluorescent protein has at least 95% sequence identity with an amino acid sequence, either contiguous or non-contiguous, from the wild type Aequorea green fluorescent protein of SwissProt Accession No. P42212. Similarly, the fluorescent protein may be related to Renilla or Phialidium wild-type fluorescent proteins using the same standards.
[0124] Aequorea -related fluorescent proteins include, for example, wild-type (native) Aequorea victoria GFP, whose nucleotide and deduced amino acid sequences are presented in Genbank Accession Nos. L29345, M62654, M62653 and others Aequorea -related engineered versions of Green Fluorescent Protein, of which some are listed above. Several of these, i.e. P4, P4-3, W7 and W2, fluoresce at a distinctly shorter wavelength than wild type.
Identification of Insertion and Excision Events
[0125] Minos transposons, and sites from which transposons have been excised, may be identified by sequence analysis. Minos typically integrates at a TA base pair, and on excision leaves behind a duplication of the target TA sequence, flanking the four terminal nucleotides of the transposon. The presence of this sequence, or related sequences, may be detected by techniques such as sequencing, PCR and/or hybridisation.
[0126] Inserted transposons may be identified by similar techniques, for example using PCR primers complementary to the terminal repeat sequences.
Regulation of Transposase Expression
[0127] Coding sequences encoding the transposase may be operatively linked to regulatory sequences which modulate transposase expression as desired. Control sequences operably linked to sequences encoding the transposase include promoters/enhancers and other expression regulation signals. These control sequences may be selected to be compatible with the host organism in which the expression of the transposase is required. The term promoter is well-known in the art and encompasses nucleic acid regions ranging in size and complexity from minimal promoters to promoters including upstream elements and enhancers.
[0128] The promoter is typically selected from promoters which are functional in cell types homologous to the organism in question, or the genus, family, order, kingdom or other classification to which that organism belongs, although heterologous promoters may function—e.g. some prokaryotic promoters are functional in eukaryotic cells. The promoter may be derived from promoter sequences of viral or eukaryotic genes. For example, it may be a promoter derived from the genome of a cell in which expression is to occur. With respect to eukaryotic promoters, they may be promoters that function in a ubiquitous manner (such as promoters of α-actin, β-actin, tubulin) or, alternatively, a tissue-specific manner (such as promoters of the genes for pyruvate kinase). They may also be promoters that respond to specific stimuli, for example promoters that bind steroid hormone receptors. Viral promoters may also be used, for example the Moloney murine leukaemia virus long terminal repeat (MMLV LTR) promoter, the rous sarcoma virus (RSV) LTR promoter or the human cytomegalovirus (CMV) IE promoter.
[0129] It is moreover advantageous for the promoters to be inducible so that the levels of expression of the transposase can be regulated. Inducible means that the levels of expression obtained using the promoter can be regulated. A widely used system of this kind in mammalian cells is the tetO promoter-operator, combined with the tetracycline/doxycycline-repressible transcriptional activator tTA, also called Tet-Off gene expression system (Gossen, M. & Bujard, H., (1992) Tight control of gene expression in mammalian cells by tetracycline responsive promoters, Proc. Natl. Acad. Sci. U.S.A. 89:5547-5551), or the doxycycline-inducible rtTA transcriptional activator, also called Tet-On system (Gossen, M., Freundlieb, S., Bender, G., Muller, G., Hillen, W. & Bujard, H., (1995) Transcriptional activation by tetracycline in mammalian cells, Science 268:1766-1769).
[0130] In the Tet-Off system, gene expression is turned on when tetracycline (Tc) or doxycycline (Dox; a Tc derivative) is removed from the culture medium. In contrast, expression is turned on in the Tet-On system by the addition of Dox. Procedures for establishing cell lines carrying the transcriptional activator gene and the Tet-regulatable gene stably integrated in its chromosomes have been described. For example see http://www.clontech.com/techinfo/manuals/PDF/PT3001-1.pdf. For example, the Tet-On system may be employed for tetracycline-inducible expression of Minos transposase in a transgenic animal. A doubly transgenic animal is generated by standard homologous recombination ES cell technology. Two constructs are used: first, a construct containing the rtTA gene under a constitutive promoter. An example of such construct is the pTet-On plasmid (Clontech) which contains the gene encoding the rtTA activator under control of the Cytomegalovirus immediate early (CMV) promoter. The rtTA transcriptional activator encoded by this construct is active only in the presence of Doxycycline. The second construct contains the Minos transposase gene under control of the tetracycline-response element, or TRE. The TRE consists of seven direct repeats of a 42-bp sequence containing the tet operator (tetO), and is located just upstream of the minimal CMV promoter, which lacks the enhancer elements normally associated with the CMV immediate early promoter. Because these enhancer elements are missing, there is no “leaky” expression of transposase from the TRE in the absence of binding by rtTA. An example of such construct is the pTRE2 plasmid (Clontech) in the MCS of which is inserted the gene encoding Minos transposase. In cells stably transformed with the two constructs, rtTA is expressed but does not activate transcription of Minos transposase unless Doxycycline is administered to the animal.
[0131] Alternative inducible systems include or tamoxifen inducible transposase (a modified oestrogen receptor domain (Indra et al., (1999) Nucl. Acid Res. 27:4324-27) coupled to the transposase which retains it in the cytoplasm until tamoxifen is given to the culture), or a RU418 inducible transposase (operating under the same principle with the glucocorticoid receptor; see Tsujita et al., (1999) J. Neuroscience 19:10318-23).
[0132] In addition, any of these promoters may be modified by the addition of further regulatory sequences, for example enhancer sequences. Chimeric promoters may also be used comprising sequence elements from two or more different promoters described above.
[0133] The use of locus control regions (LCRs) is particularly preferred. LCRs are capable of conferring tightly-regulated tissue specific control on transgenes, and to greatly increase the fidelity of transgene expression. A number of LCRs are known in the art. These include the β-globin LCR (Grosveld et al., (1987) Cell 51:975-985); α-globin (Hatton et al., (1990) Blood 76:221-227; and CD2 (Festenstein et al., (1996) Science 271:1123-1125), plus immunoglobulins, muscle tissue, and the like.
[0134] Regulation of transposase and/or transposon expression may also be achieved through the use of ES cells. Using transformed ES cells to construct chimeric embryos, it is possible to produce transgenic organisms which contain the transposase genes or transposon element in only certain of their tissues. This can provide a further level of regulation.
[0135] The regulation of expression of transposase may induce excision of a transposon. This may be used to genetically manipulate an organism. As used herein, the term “genetically manipulate” refers to the manipulation of genes in an organism's genome and may include the insertion or excision of a gene or part of a gene.
[0136] The sequence of the transposase may be modified to optimise codon usage and thus, increase transposition frequencies. “Codon usage” refers to the frequency pattern in which a given organism uses the 64 possible 3 letter codons of the genetic code in its coding sequences. Because of codon usage preferences, transgenes exhibiting a codon usage pattern more similar to that of the transgenic host organism will generally be more efficiently expressed than those exhibiting a widely differing codon usage pattern. Optimisation of codon usage by converting less frequently used codons to more frequently used codons is a method well known in the art to increase the expression levels of a given gene. Information on codon usage is widely known for a broad range of species (see, e.g., “Codon Usage Tabulated From The International DNA Sequence Databases Status For The Year 2000,” Nakamura et al., Nucl. Acids Res. 28, 292). Codon usage is considered “optimized” when at least one codon in the transposase coding region is replaced with a codon that is used more frequently (i.e., at least 1% more frequently, but preferably at least 5%, 10%, 15%, 20% or more) in the transgenic host species than that encoded by the species from which the transposase is originally taken.
[0137] The invention is further described, for the purpose of illustration, in the following examples.
EXAMPLES
Plasmid Constructions
[0138] The helper plasmid CD2/ILMi is constructed by subcloning the transposase cDNA (Klinakis et al., (2000) EMBO reports 1:16-421) as an XbaI-blunt fragment into the vector SVA(−). The SVA(−) vector is a derivative of the VA vector (Zhumabekov et al., (1995) J. Immunol. Methods 185:133-140) with extended multiple cloning sites.
[0139] Transposon MiCMVGFP is constructed as follows: The plasmid pMILRTetR (Klinakis et al., (2000) Ins. Mol. Biol. 9:269-275 (2000b) is cut with BamHI and re-ligated to remove the tetracycline resistance gene between the Minos ends, resulting in plasmid pMILRΔBamH1. An Asp718/SacI fragment from pMILRΔBamH1, containing the Minos inverted repeats and original flanking sequences from D. hydei , is cloned into plasmid pPolyIII-I-lox (created by insertion of the loxP oligo:
[0000] ATAACTTCGTATAGCATACATTATACGAAGTTAT
into the Asp718 site of the vector pPolyIII-I (accession No. M18131), resulting in plasmid ppolyMILRΔBamH. The final construct (pMiCMVGFP, FIG. 1 ) used for the generation of transgenic mice, is created by inserting into the Spe I site of ppolyMILRΔBamH1 the 2.2 kb SpeI fragment from plasmid pBluescriptGFP, containing a humanised GFP gene (from Clontech plasmid pHGFP-S65T) driven by the CMV promoter and followed by the SV40 intervening sequence and polyadenylation signal.
[0140] Plasmid pJGD/ILMi ( FIG. 1 ) is constructed as follows: A 1 kb EcoRV/NotI fragment containing the Minos transposase cDNA is cloned into EcoRV/NotI of plasmid pJG-3 (the puro variant of pJG-1; Drabek et al., (1997) Gene Ther. 4:93-100. The resulting plasmid (pJGD/transposase) that carries a CMV promoter upstream of the transposase cDNA, an intron with splice site and polyA from the human β globin gene and the puromycin resistance gene driven by PGK promoter and followed by the poly(A) signal from the bovine growth hormone gene is used as the transposase source in transfections of embryonic fibroblasts.
Generation of Transgenic Mice
[0141] The transposase-expressing TM2 mouse line is generated by injecting the 12.5 kb SfiI fragment from the CD2/ILMi plasmid ( FIG. 1 ) into CBA×C57 B1/10 fertilized oocytes. Transgenic founder animals are identified by Southern blotting of DNA from tail biopsies, using the 1 kb transposase cDNA fragment as a probe and crossed with F1 CBA×C57 B1/10 mice to generate lines.
[0142] The transposon-carrying MCG line is constructed by injecting the 3.2 kb XhoI fragment from the pMiCMVGFP plasmid into FVB×FVB fertilized oocytes. Transgenic founder animals are identified by Southern blotting of DNA from tail biopsies, using GFP DNA as a probe.
[0143] Cell Culture, Transfection
[0144] 13.5 day pregnant females (from crosses between MCG heterozygous transgenic male and wt females) are sacrificed, embryos are isolated and part of the material is used for genotyping. The remaining embryonic tissue is minced using a pair of scissors and immersed in a thin layer of F10/DMEM culture medium supplemented with 10% FCS and antibiotics. Two spontaneously immortalized mouse embryonic fibroblasts lines (MEFs) with MCG/+genotype are obtained by subculturing of primary MEFs. They are stably transfected with 20 μg of plasmid pJGD/ILMi linearised with ScaI, using Lipofectin (GibcoBRL). Transfectants are selected on puromycin at a concentration of 1 μg/ml.
Northern Blot Hybridisation
[0145] 15 μg of total RNA isolated (Chomozynski & Sacchi, (1987) Analytical Biochem. 162:156-159) from kidney, thymus and spleen is subjected to electrophoresis in a 1.2% agarose gel containing 15% formaldehyde. Northern blot analysis is performed as described previously (Sambrook et al., (1989) Molecular Cloning, A Laboratory Manual, Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y.).
PCR Analysis
[0146] Genomic DNA from different tissues is isolated with the DNeasy Tissue-Kit (QIAGEN) according to the manufacturer's instructions. PCR reactions are performed using primers 11DML:
[0000]
(5′AAGTGTAAGTGCTTGAAATGC-3′)
and GOUM67:
[0147]
[0000]
(5′-GCATCAAATTGAGTTTTGCTC-3′).
[0148] PCR conditions are as follows: 10 mM Tris-HCl (pH 8.8), 50 mM KCl, 1.5 mM MgCl 2 , 0.001% gelatin; 1.2 units Taq 2000™ DNA Polymerase (STRATAGENE), 200 g template DNA and 10 pmol of each primer per 25 μl A reaction. 43 or 60 cycles of 30″ at 94° C., 30″ at 59° C. and 30″ at 72° C. were performed. PCR products are cloned into the PCRII TA cloning vector (Invitrogen) and are sequenced using the T7 primer.
DNA Fluorescent In Situ Hybridisation (FISH) Analysis
[0149] Cells from minced thymus or spleen are cultured for 48 h in RPMI medium (GIBCO BRL) supplemented with 9% FCS (GIBCO BRL), 13.6% Hybridoma medium (GIBCO BRL), 3.4 μg/ml Lithium chloride (MERCK), 7.2 μg/ml Concanavaline-A (SIGMA), 22.7 i.u./ml Heparine (LEO), 50 μM Mercaptoethanol, 25.4 μg/ml L.P.S. (SIGMA), 10 ng/ml interleukin 6 (PEPROTECH EC LTD). Chromosome preparations and FISH are carried out as described previously (Mulder et al., (1995) Hum. Genet. 96:133-141). The 737 bp SacI/NotI GFP fragment from the pMiCMVGFP construct is used as a probe. The probe is labelled with Biotin (Boehringer Manheim) and immunochemically detected with FITC. A telomeric probe for chromosome 14 (Shi et al., (1997) Genomics 45:42-47) is labelled with dioxygenin (Boehringer Manheim) and immunochemically detected with Texas Red.
Example 1
Activation of Minos In Vivo in a Tissue-Specific Manner
[0150] Two transgenic mouse lines are generated to determine whether Minos can transpose in mouse tissues: One containing a Minos transposon and another containing the Minos transposase gene expressed in a tissue-specific manner. The transposon-carrying line (line MCG) contains a tandem array of a fragment containing a Minos transposon (MiCMVGFP, FIG. 1 ) containing the GFP gene under the control of the cytomegalovirus promoter. The transposon is engineered such that almost all sequence internal to the inverted repeats is replaced by the CMV/GFP cassette. Not containing the transposase-encoding gene, this transposon is non-autonomous, and can only be mobilized when a source of transposase is present. The transposase-expressing line (line TM2) contains a tandem array of a construct comprising the Minos transposase cDNA under the control of the human CD2 locus, consisting of the CD2 promoter and LCR elements (pCD2/ILMi, FIG. 1 ). In transgenic mice, the human CD2 locus is transcribed at high levels in virtually all thymocytes as well as peripheral T cells (Zhumabekov et al., (1995) J. Immunol. Methods 185:133-140).
[0151] Heterozygous TM2/+ mice are tested for tissue-specific production of Minos transposase RNA by Northern blot analysis. Minos transposase mRNA is detected in thymus and spleen, the two organs with large numbers of T cells, but is not detected in other organs such as kidney ( FIG. 2 ).
[0152] A PCR assay for transposon excision is used to detect active transposition by Minos transposase in mouse tissues, using primers that hybridise to the non-mobile Drosophila hydei sequences which flank the Minos transposon in the constructs shown in FIG. 1 (Klinakisv et al., (2000) Ins. Mol. Biol. 9:269-275). In Drosophila cells, transposase-mediated excision of Minos is followed by repair of the chromatid which usually leaves a characteristic 6-base pair footprint (Arca et al., (1997) Genetics 145:267-279). With the specific pair of primers used in the PCR assay this creates a diagnostic 167 bp PCR fragment (Catteruccia et al., (2000) Proc. Natl. Acad. Sci. U.S.A. 97:2157-2162). As shown in FIG. 3 , the diagnostic band is present in tissues of double transgenic (MCG/+TM2/+) mice expressing the transposase, but not of MCG/+ mice, not expressing transposase. The identity of the fragment is confirmed by Southern blot analysis using a labelled DNA probe specific for the amplified sequence (data not shown). Excision is detectable mainly in thymus and spleen of the double transgenics; lower levels of excision are detectable in liver ( FIG. 3 ). Very low levels of excision can also be detected in kidney, brain, and skeletal muscle, after 15 additional cycles of amplification (data not shown). Low levels of expression of the human CD2 locus in liver and lung of transgenic mice has been documented previously (Lang et al., (1988) EMBO J. 6:1675-1682). We therefore attribute the excision detected in tissues other than thymus and spleen to the presence of small numbers of T cells or to the expression of transposase in non-T cells of these tissues due to position effects.
Example 2
Detection of Transposition in Cultured Embryonic Fibroblasts
[0153] The PCR excision assay is used to detect Minos excision in cultured embryonic fibroblasts carrying the MCG transgene. Cells are transfected with a plasmid carrying the Minos transposase cDNA under CMV control (pJGD/ILMi, FIG. 1 ) and analysed by the PCR excision assay. Excision products are detectable in transfected but not in non-transfected cells (data not shown). This result suggests that the transposon transgene is accessible to the Minos transposase in tissues other than T cells.
Example 3
Detection of Excision Events
[0154] To determine the nature of the excision events, PCR products from thymus and spleen of MCG/+TM2/+ mice and from pJGD/ILMi transfected embryonic fibroblasts are cloned and sequenced. The sequence left behind after Minos excision in Drosophila consists of the TA dinucleotide duplication that is created upon Minos insertion, flanking the terminal 4 nucleotides of the transposon (i.e. either a AcgagT or a ActcgT insertion in the TA target site). In the mouse excisions analysed, the size and sequence of the footprints varies considerably ( FIG. 4 ). Only 2 of the 32 footprints have the typical 6 bp sequence; the others contain extra nucleotides, in addition to complete or partial versions of the typical footprint. Four events have 1-2 nucleotides of the flanking D. hydei chromosomal sequence deleted. The differences in footprint structures observed between Drosophila and mouse may reflect the involvement of host factors in Minos excision and/or chromatid repair following excision.
Example 4
Detection of Transposition in Transgenic Mice Using FISH
[0155] Detection of transposase-dependent excision in thymus and spleen suggests that transposition may also take place in these tissues. The detection of transposition events is not straightforward, because every transposition event is unique, and as a result the tissue in which transposition has occurred will be a mosaic of cells with unique transpositions. Indeed, Southern analysis did not show transposition events in the thymus of double transgenics, indicating that, if such mosaics exists, they consist of small numbers of clonally related cells.
[0156] Therefore, FISH in metaphase nuclei from the thymus and spleen to detect individual transposition events. A GFP fragment is used as a probe to detect relocalisation of transposons into new chromosomal positions. The initial position of the array of transposons is at the tip of chromosome 14, at a position indistinguishable from the telomere, as shown by co-localization, in metaphase and interphase chromosomes, with a probe specific for telomeric sequences of chromosome 14 ( FIG. 5 , A-B). A total of 3,114 metaphases from 5 MCG/+TM2/+ mice are analysed; 1,688 are from spleen and 1,426 from thymus. Nineteen of these metaphases (11 from spleen and 8 from thymus) show transposition. In addition to the signal at the tip of chromosome 14, pairs of dots are present in these metaphases on chromosomes other than 14, or on a new position on chromosome 14. Representative metaphases are shown in FIG. 5 (C-F). Morphological analysis of the chromosomes carrying new insertions show that all events except one are independent from each other, i.e. they represent different transpositions. Analysis of the positive metaphases with a probe specific for the telomere of chromosome 14 indicates that transpositions do not involve translocation of telomeric material (data not shown). As controls, 2,440 metaphases from thymus and spleens of five MCG/+ mice are screened; no transpositions are detectable in those samples.
[0157] This is the first demonstration that a transposase expressed from a transgene can mobilize a transposon to jump into new chromosomal sites in mammalian tissues.
[0158] All publications mentioned in the above specification are herein incorporated by reference. Various modifications and variations of the described methods and system of the invention will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in molecular biology or related fields are intended to be within the scope of the following claims.
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The invention relates to a method for generating a transgenic organism. The invention also relates to a method for detecting and characterizing a genetic mutation in a transgenic organism. The invention further relates to a method for isolating a gene which is correlated with a phenotypic characteristic in a transgenic animal. The invention further relates to a method for isolating an exon in a transgenic animal. The invention also relates to a method for modulating the expression of a gene in an organism.
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BACKGROUND OF THE INVENTION
Mechanized car washes can snag a license plate attached to a vehicle or the Original Equipment Manufacturer (OEM) license plate bracket, bending the license plate or causing damage to the license plate bracket and/or the vehicle, or both. It is known that an OEM license plate bracket may be removed from a vehicle prior to washing the vehicle using the mechanized car wash. Removal and reattachment of known OEM license plate bracket may require a specific tool or may be time intensive, or both.
Aftermarket equipment to replace the OEM license plate bracket is known. Aftermarket equipment may be marketed as more resistant to damage associated with mechanized car washes. However, aftermarket equipment may be installed differently on the vehicle than the OEM license plate bracket, which can create compatibility issues with other vehicle equipment, such as parking sensors. For example, if the aftermarket equipment extends too far from the vehicle, the parking sensor could be erroneously triggered; however, this is only one example of possible compatibility issues (other compatibility issues may involve interference with cruise control or other sensors, radiator operation, etc.). In addition, as the configuration/condition of the mechanized car washes can vary from one location or another, it is still possible to have damage when using a mechanized car wash with the aftermarket equipment installed, and removal/reattachment of some known aftermarket license plate equipment may require the same specific tool or may still be time intensive, or both.
SUMMARY OF THE INVENTION
The following is a summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not intended to identify key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concepts of the invention in a simplified form as a prelude to the more detailed description that is presented later.
In an example, a quick release license plate holder with a low and/or compact profile is provided. In an example, the holder includes a bolt assembly having a first end to attach to a vehicle and a second end to quick release a support plate for holding the vehicle license plate. In an example, the quick release and re-attachment may be tool-less and/or may not require a re-leveling (e.g. may not require re-leveling after removal and reattachment for, say, utilizing a mechanized car wash). In another example, the quick release may not require the same specific tool as a typical OEM license plate bracket and/or may require less application of the same specific tool.
In an example, the support plate slidingly engages with the second end of the bolt assembly. The support plate includes a front surface to engage with the vehicle license plate and a back surface having a shoe. In an example, the shoe forms an enclosure with a portion of the back surface of the support plate to provide a low and/or compact profile. In an example, the second end of the bolt assembly comprises a cleat having at least one edge structured to be removeably inserted into the enclosure.
Additional aspects and advantages of this invention will be apparent from the following detailed description of preferred embodiments, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates license plate holder with a quick release feature.
FIG. 2 illustrates a process for installing the license plate holder of FIG. 1 .
FIG. 3 illustrates a front view of an example bolt assembly and a rear view of an example support plate for a low and/or compact license plate holder.
FIG. 4 illustrates a cross-sectional side view of a portion of the bolt assembly of FIG. 3 .
FIG. 5 illustrates another example of a license plate holder.
FIG. 6 illustrates a cross-sectional side view of the license plate holder of FIG. 5 .
FIG. 7 illustrates an exploded view of the bolt assembly of the license plate holder of FIG. 5 .
FIG. 8 illustrates a quick release the support plate of the license plate holder of FIG. 5 from the bolt assembly.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 illustrates license plate holder with a quick release feature.
The bolt assembly 100 includes a first end 8 and a second end 11 . The first end 8 may be threaded for installation in a threaded hole of a motor vehicle. In an example, the second end 11 may be rotatable relative to a remainder of the bolt assembly 100 , e.g. the first end 8 . In another example, the second end 11 may be rotatable and pivotable relative to a remainder of the bolt assembly 100 .
The support plate 101 includes a first surface to which a license plate may be attached and a second surface. The second surface may correspond to a connector 12 to mate with the second end 11 of the bolt assembly 100 . The connector 12 may be structured to releasably couple, e.g. slidingly engage, to the second end 11 .
In an example, the support plate 101 may be manufactured using sheet metal. In one such example, the first end 8 may include at least one prong, and the second end 11 may include an opening to mate with the prong. In an example, a support plate manufactured using sheet metal includes at least one tongue to form an opening to receive a prong of the first end 8 . The support plate manufactured using sheet metal may include an indented portion with an opening on the top or bottom, e.g. a slit cut on the top or bottom of the indented portion.
FIG. 2 illustrates a process for installing the license plate holder of FIG. 1 onto a vehicle.
In block 201 , support plate 101 is attached to the end 11 of the bolt assembly 100 , e.g. slidingly engaged with the end 11 of the bolt assembly 100 . In block 202 , the support plate 101 may be used as a wrench to drive the threaded end 8 of the bolt assembly 100 into a motor vehicle.
In block 203 , after driving the threaded end 8 of the bolt assembly 100 into the motor vehicle, the support plate 100 may be detached, e.g. released, from the end 11 of the bolt assembly 100 . In block 204 , a user may partially rotate the end 11 of the bolt assembly 100 relative to the threaded end 8 of the bolt assembly 100 for leveling. In an example, a component of the bolt assembly 100 may be loosened, released, removed, etc., in order to partially rotate the end 11 . For example, a tool such as a hex key may be used to loosen at least one fastener to allow the partial rotation, and the fastener(s) may be tightened once the leveling is complete.
In block 205 , the support plate 101 may be re-attached to the bolt assembly 101 . In an example, the re-attachment may include slidingly engaging the support plate 101 with the bolt assembly 100 .
FIG. 3 illustrates a front view of an example bolt assembly and a rear view of an example support plate for a low and/or compact profile license plate holder.
The bolt assembly 310 includes a cleat 31 . The support plate 311 includes a back surface having a plurality 36 of holes arranged in a matrix. The matrix is a 2×5 matrix in the illustrated example, although in other examples the matrix may be greater or smaller than the illustrated matrix, for example a 2×8 matrix, a 3×11 matrix, etc. In an example, the cleat has at least one member 32 .
A shoe 38 is mounted on a selected subset of the holes of the plurality 36 . In an example, the exposed surface of the shoe 38 has a u-shape. The subset of the plurality 36 may be selected for compatibility in regard to positioning the license plate on the vehicle and/or user preference. In the illustrated example, the shoe 38 is mounted as an upside down “U”. In other examples where the matrix includes at least three rows of holes, the shoe 38 may be mounted as a forwards or backwards “C” to maximize compatibility in regard to positioning the license plate on the vehicle and/or user preference, which may address compatibility concerns with regard to sensors, radiator operation, etc.
The opposite surface of the shoe 38 , i.e. a surface that makes contact with the back surface of the support plate 311 , has a smaller footprint (illustrated by the dashed line 39 ). The shoe 38 forms an enclosure with a portion of the back surface of the support plate 311 . A portion of an edge of the cleat 31 may be removably inserted into the enclosure that is formed by portion of the back surface of the support plate 311 and the shoe 38 to mount the support plate 311 on the bolt assembly 310 . When the cleat 31 is removably inserted into the enclosure that formed by portion of the back surface of the support plate 311 and the shoe 38 , the front surface of the cleat 31 is adjacent to the back surface of the support plate 311 .
The opposite surface of the shoe 38 may also be u-shaped with at least one cutout. Each cutout may correspond to a member of the at least one member 32 . In an example, the cutout only partially defines an opening for at least one member 32 of the cleat 31 (the opening is defined by the opposite surface of the shoe 38 and the back surface of the support plate 311 ). In an example, the member 32 extends through the opening defined by the opposite surface of the shoe 38 and the back surface of the support plate 311 . The protruding portion of the member 32 may have a pinhole (not illustrated) through which a pin, e.g. a cotter pin, may be inserted in order to secure the support plate 311 to the bolt assembly 310 . In the example including the pinhole, the pin when inserted may be oriented parallel to the back surface of the support plate 311 .
It is noted that the demarking of the dashed line 39 applies to this particular example. In other examples, the footprint of the back surface of the shoe 38 is larger than the footprint of the opposite surfaces in order to form the enclosure with a portion of the back surface of the support plate 311 , but neither footprint necessarily need to have the same shape or dimensions shown. In another example, the overhang may correspond to only a portion of the interior edge of the shoe 38 , e.g. the oppositely facing interior edges.
FIG. 4 illustrates a cross-sectional side view of a portion of the bolt assembly of FIG. 3 .
A portion of a stud 401 of the bolt assembly 310 is shown (the end for securing to the vehicle, e.g. a threaded end, is not shown). An end of the stud 401 includes a cup having an inner sidewall to mate with a partial sphere 406 . In an example, the partial sphere 406 may be constructed from a different material than the stud 401 , e.g. plastic.
A collar 408 having a curved interior surface slips over the stud 401 to mate with an outer sidewall of the cup. The collar 408 may have one or more openings (not illustrated) by which a plurality 409 of fasteners such as hex end screws may be used to connect the cleat 31 and the collar 408 .
When the fasteners of the plurality 409 are inserted but not tightened, e.g. loosened, the cleat 31 may be pivoted relative to the stud 401 for leveling and/or other adjustment. The surfaces of the fasteners of the plurality 409 may be flush or recessed with respect to the front surface of the cleat 31 when tightened. When tightened, the collar 408 and the cleat 31 operate as a clamp to fix a position of the collar 408 , the partial sphere 406 , and the cleat 31 relative to the stud 401 .
Referring now to FIGS. 3 and 4 , it can be seen that the quick release license plate holder has a low and/or compact profile, which may reduce compatibility concerns with certain vehicles such as vehicles with parking sensors. A portion of the front surface of the cleat 31 may make contact with a portion of the back surface of the support plate 35 .
The thickness of the cleat 31 may be determined based on numerous application specific variables, including but not limited to application requirements, the size of the front surface of the cleat 31 , the material used for the cleat 31 , operating environment, etc. However, when the cleat 31 is removably inserted into the enclosure formed by the back surface of the support plate 311 and the shoe 38 , a distance between the back surface of the support plate 311 and a front surface of a component of the bolt assembly 310 corresponds to the thickness of the cleat 31 . In the illustrated example, the distance between the back surface of the support plate 311 and the front surface of the collar 408 corresponds to the thickness of the cleat 31 .
FIG. 5 illustrates another example of a license plate holder.
The license plate holder 500 includes a 3×11 matrix of holes for mounting a shoe. The license plate holder 500 also includes larger openings 510 , e.g. larger holes, for weight reduction. The remaining holes 512 are for attaching a license plate to a front of the support plate 516 of the license plate holder 500 .
FIG. 6 illustrates a cross-sectional side view of the license plate holder of FIG. 5 .
In FIG. 6 , the license plate 515 is shown attached to the front of the support plate 516 . The front of the support plate 516 has a shape to mate with a shape of a back of the license plate 515 .
FIG. 7 illustrates an exploded view of the bolt assembly of the license plate holder of FIG. 5 .
The cleat 531 includes two members 532 . FIG. 8 illustrates that each of the members 532 is removed from an enclosures that is formed by portion of the back surface of the support plate 516 and the shoe 538 (after the cotter pins 599 are removed), which releases the support plate 516 from a vehicle.
It will be obvious to those having skill in the art that many changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. The scope of the present invention should, therefore, be determined only by the following claims.
Having described and illustrated the principles of the invention in a preferred embodiment thereof, it should be apparent that the invention may be modified in arrangement and detail without departing from such principles. We claim all modifications and variations coming within the spirit and scope of the following claims.
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In an example, a quick release license plate holder with a low and/or compact profile is provided. In an example, the holder includes a bolt assembly having a first end to attach to a vehicle and a second end to quick release a support plate for holding the vehicle license plate. In an example, the quick release and re-attachment may be tool-less and/or may not require a re-leveling. In another example, the quick release may not require the same specific tool as a typical OEM license plate bracket and/or may require less application of the same specific tool.
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PRIORITY CLAIM
[0001] This application is based on and claims priority benefits from UK Patent Application No. 1401604.2 filed on Jan. 30, 2014, the entire content of which is expressly incorporated hereinto by reference.
FIELD
[0002] The present invention relates to cleaning of particulate material from refinery processes or power generation systems, including, but not limited to selective catalyst reduction (“SCR”) catalysts, or components of an SCR system, or convection sections of refinery processes or a power generation system.
BACKGROUND
[0003] SCR systems are employed to remove Nitrogen Oxides (NOx) from spent flue gas. Nitrogen Oxides pose pollutions problems, whereas the NOx can react in the atmosphere with water vapor to produce to acid rain, or react with sunlight to produce ozone. NOx forms during combustion of fuel to heat furnaces, including but not limited to, hydrogen reformers, vacuum heaters, platformers, and other process heaters. NOx can form in three ways during combustion: Thermal, Fuel, and Prompt NOx.
[0004] The purpose of a SCR system is to convert the Nitrogen Oxides into diatomic Nitrogen (N2). The system uses liquid ammonia and a porous catalyst to convert the NOx. The ammonia is injected with air into the flue gas at a controlled ratio, and the Nitrogen oxides react with the ammonia and oxygen to form diatomic Nitrogen and water. The catalyst increases the conversion rate to over 90%. The Nitrogen and water can then be safely released into the atmosphere.
[0005] The interior of a furnace is lined with refractory ceramic fiber (RCF), insulating refractory brick, or a combination of the two. The RCF is composed of amorphous silica, that when subjected to elevated temperatures, such as in a platformer, will devitrify into crystalline silica and other components. Due to the gas velocity in the furnace, the crystalline silica is picked up in the gas flow and carried downstream. Likewise, the gas velocity and water vapor can act as an abrasive to the insulating refractory, and by a process known as silica migration, particulates from the insulating refractory can also be gathered and carried. Also, during combustion of fuel, in particular, oil, particulates can be generated and also carried downstream in a process known as oil dusting, for example. These particles can be deposited on the surface of the catalyst and contaminate the generally porous surface of a catalyst, or on heat transfer vanes of a convection section of a furnace. These cannot only reduce the effectiveness of the catalyst, but can also damage or poison the catalyst, leading to reduced performance. In the case of heat transfer vanes, the particulates act as insulators; this contamination thus reduces the heat transfer efficiency of the unit.
[0006] In order to overcome such issues, various ways of cleaning the contaminated units have been employed. One known method involves use of a sonic horn, to generate sound waves to dislodge particulates from the contaminated unit, which are then expelled with the flue gas. However, these particles may also become lodged in the channels of the catalyst, or fall to the bottom of the unit and collect. Another method involves blasting, typically with dry ice, which as it sublimes in the region of the particulates causes them to be dislodged from the contaminated unit.
SUMMARY
[0007] The embodiments disclosed herein seek to overcome or ameliorate at least one of the problems of the prior art or provide a useful alternative. Generally, methods and apparatus are provided whereby a component can be cleaned while the furnace is operational, or “on-line”. Additionally, particulates that have accumulated on the component can be collected and retained, whereas previously, these would have been exhausted into the atmosphere, causing pollution.
[0008] According to some embodiments, an apparatus for removing accumulated particulates from a component will comprise a portable frame, a tubular lance supported by the frame and having a nozzle at a distal end thereof, and a suction generator operatively connected to a proximal end of the lance to generate a suction at the nozzle, wherein manipulation of the lance to move the nozzle across a component allows accumulated particulates to be removed therefrom through the lance. The nozzle may be comprised of graphite. According to some embodiments, the distal end of the lance may be at substantially a right angle relative to a longitudinal axis thereof.
[0009] The suction generator may be a static venturi device having inlet and outlet ends for passage therethrough of a flow of pressurized fluid, and a suction port, and wherein the apparatus comprises a flexible hose connecting the proximal end of the lance to the suction port of the venturi device. Other suction generators, e.g., vacuum pumps, may however be satisfactorily employed. According to those embodiments wherein the suction generator is a venturi device, the device will include inlet and outlet ends for passage therethrough of a flow of pressurized fluid, and a suction port. A flexible hose may thus be provided to connect the proximal end of the lance to the suction port of the venturi device. A filter assembly having an inlet end may be fluid-connected to the outlet end of the venturi device. According to such embodiments, therefore, the filter assembly will thereby receive a flow of pressurized fluid with entrained particulates from the outlet end of the venturi device and discharge a substantially particulate-free pressurized fluid flow through the discharge end of the filter assembly.
[0010] The frame may comprise a guide collar assembly having a tubular supporting collar surrounding the lance. The guide collar assembly according to some embodiments may include a support cradle, wherein the supporting collar is movably connected to the support cradle by a connection pin. Certain embodiments of the frame will be comprised of a separated pair of upright supports, and a gantry beam attached to and spanning the upright supports. The pair of upright supports may be height adjustable. A trolley may be movably coupled to the gantry beam such that a counterbalance device will interconnect the trolley and the lance. The counterbalance device may comprise a retractable tethering cable connected to the proximal end of the lance.
[0011] Some embodiments will have a frame which includes at least one stabilization assembly for attachment to adjacent support beams in a vicinity of the component to be suction cleaned. The stabilization assembly may comprise a coupling member connectable to the frame, a connecting plate connectable to an adjacent support beam in the vicinity of the component, and a turnbuckle assembly interconnecting the coupling member and the connecting plate.
[0012] In use, an apparatus according to the embodiments described herein may be positioned adjacent a component from which particulates are to be removed (e.g., SCR catalyst used in a SCR system), and operating the suction generator to generate a suction at the nozzle of the lance. The lance may be manipulated to move the nozzle across the component to cause particulates to be removed therefrom by the generated suction, following which the removed particulates may be transported from the component through the lance.
[0013] As noted previously, the suction may be generated at the nozzle by means of a venturi device which generates a suction in response to a flow of pressurized fluid (air) therethrough. The particulates transported from the component through the lance will therefore be entrained in such fluid flow which can thereafter be directed to a filter assembly. The entrained particulates may thus be removed by suitable filter media in the filter assembly, following which substantially particulate-free fluid (air) may be discharged to the ambient environment.
[0014] These and other aspects and advantages of the present invention will become more clear after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
[0015] The disclosed embodiments of the present invention will be better and more completely understood by referring to the following detailed description of exemplary non-limiting illustrative embodiments in conjunction with the drawings of which:
[0016] FIG. 1 is a perspective view showing an apparatus according to an embodiment of the invention;
[0017] FIG. 2 is an enlarged perspective view of the mounting assembly employed in the apparatus depicted in FIG. 1 ;
[0018] FIG. 3 is an even further enlarged perspective view of the guide collar assembly employed in the mounting assembly depicted in FIG. 2 ;
[0019] FIG. 4 is a further perspective view partly in section of the guide collar assembly taken along line 4 - 4 in FIG. 3 and showing longitudinal movement of the vacuum lance permitted thereby;
[0020] FIG. 5 is a perspective view partly in section of the guide collar assembly similar to FIG. 4 but showing the pivotal movement of the vacuum lance permitted thereby;
[0021] FIG. 6 is a perspective view partly in section of the guide collar assembly similar to FIG. 4 but showing the latitudinal movement of the vacuum lance permitted thereby;
[0022] FIG. 7 is view of a venturi effect device that may be used with the apparatus depicted in FIG. 1 ;
[0023] FIG. 8 is a cross-sectional elevational view of a filter assembly that may be used with the apparatus depicted in FIG. 1 ;
[0024] FIG. 9 is a perspective view showing an apparatus according to another embodiment of the invention; and
[0025] FIG. 10 is a perspective view of a clamping assembly for use with the apparatus depicted in FIG. 9 .
DETAILED DESCRIPTION
[0026] An apparatus 10 according to an embodiment of the invention for removing accumulated particulates from an SCR or convection system (schematically represented by reference numeral 12 ) while the system 12 is operational is depicted the accompanying FIGS. 1-6 . As shown, the apparatus 10 generally includes a frame assembly 14 comprised of a pair of spaced-apart vertical supports 16 a, 16 b having lower ends received within a vertical branch 18 a, 20 a of the tubular couplings 18 , 20 , respectively. The frame 14 likewise has pairs of downwardly divergent leg supports 22 - 1 , 22 - 2 and 24 - 1 , 24 - 2 having upper ends received within a respective one of the leg branches 18 - 1 , 18 - 2 and 20 - 1 , 20 - 2 , respectively, of the couplings 18 , 20 . Base supports 30 , 32 span the distance between the lower ends of leg supports 22 - 1 , 24 - 1 and 22 - 2 , 24 - 2 , respectively. Casters 34 may be mounted to the lower end of each leg support 22 - 1 , 22 - 2 , 24 - 1 and 24 - 2 to allow the frame 14 to be maneuvered relative to an opening 12 a in the system 12 . The upper ends of the vertical supports 16 a, 16 b carry a mounting pad 36 a, 36 b to which a gantry beam 38 is attached. The vertical supports 16 a, 16 b are removably attached to the couplings 18 , 20 by means a pin and aperture arrangement 18 b, 20 b thereby allowing vertical height adjustment of the gantry beam 30 relative to the system opening 12 a in the direction of arrow A 1 .
[0027] A trolley 40 is moveably supported by the gantry beam 38 so as to be capable of reciprocal movements along the gantry beam 38 in the direction of arrow A 2 . The trolley 40 in turn dependently supports a counterbalance device 42 having a tethering cable 42 a attached to a proximal end 50 a of a rigid tubular vacuum lance 50 . The lance 50 includes a distal end 50 b which in the embodiment shown is at substantially a right angle relative to the elongate axis of the lance 50 .
[0028] The weight of the vacuum lance 50 is therefore counterbalanced by the counterbalance device 42 to allow an operator to insert the lance 50 into and remove it from the system 12 through opening 12 a. The counterbalance device 42 thus assists the operator against gravity as the lance 50 and the nozzle 52 attached at its distal end 50 b are guided into the system 12 through opening 12 a during cleaning by allowing the tethering cable to be retracted and payed-out as the lance is raised and lowered, respectively, relative to the system 12 . The nozzle 52 is most preferably a graphite head which is sufficiently soft so as to avoid damage to the relatively delicate material of the SCR catalyst (not shown) in the system 12 .
[0029] The distal end 50 b of the lance 50 is received by a guide collar assembly 60 which is perhaps better viewed by the enlarged depictions thereof in FIGS. 2-6 . In this regard, the collar assembly 60 includes a pair of spaced-apart cross-supports 62 , 64 extending between and attached to the base supports 30 , 32 . A rectangular parallelepiped shaped cradle box 66 is dependently supported by and attached between cross-supports 62 , 64 by the connecting members 68 , 70 .
[0030] The lance 50 is received within a tubular supporting collar 72 which is pivotally attached to the cradle box 66 by opposed pins 74 a, 74 b . As is shown in FIGS. 4-6 , the collar 72 has several degrees of freedom to allow movement of the lance 50 and the nozzle 52 attached to the distal end 50 b thereof relative to the material being cleaned. Specifically, the collar 72 loosely surrounds the lance 50 to allow it to be moved reciprocally upwardly and downwardly in the direction of arrow A 3 in FIG. 4 . In addition, the lance 50 may be pivoted about the longitudinal axis A L of the pins 74 a, 74 b in the direction of arrow A 4 as shown by FIG. 5 . In addition, the pins 74 a, 74 b are sufficiently long to allow for back-and-forth movements within the cradle box 66 as shown by arrow AS of FIG. 6 . In addition to the movements shown in FIGS. 4-6 by arrows A 3 -A 5 , the lance may also be rotated about its longitudinal axis to allow the nozzle 52 to be pivoted back and forth in a generally horizontal plane. Thus, the guide collar assembly 60 allows the lance 50 and the nozzle 52 attached at the distal end thereof to be manipulated and positioned as may be desired by the operator during the vacuum cleaning operation.
[0031] The proximal end 50 b of the lance 50 is attached via flexible hose 76 (see FIG. 1 ) to the suction coupling 78 a of a suction generator which in the embodiment shown is provided by a static venturi device 78 (see FIG. 7 ). The venturi device 78 produces a reduced pressure (vacuum) in the hose 76 and thus at the nozzle 52 attached at the distal end of the lance 50 by a flow of compressed air entering the venturi device 78 at its inlet end 78 - 1 and being discharged at its outlet end 78 - 2 . As is well know, this flow of compressed air within the venturi device 78 creates reduced (vacuum) pressure at the suction coupling 78 a. In this manner, therefore, a suction force is evident at the nozzle 52 attached at the distal end of the lance 50 b by virtue of the hose 76 . Alternatively, other means of generating a suction may be employed, such as dynamic vacuum pumps and the like.
[0032] As the nozzle 52 is moved across the SCR catalyst (or other material) within the system 12 as guided manually by an operator (as may be aided by a video camera (not shown) attached at the distal end 50 b of the lance 50 ), loose particulates will be suctioned out of the system 12 and travel through the lance 50 and the hose 76 to the venturi device. The loose particulates thereby suctioned from the SCR catalyst material within the system 12 will therefore be entrained by the compressed air flowing through the venturi device 78 and discharged from its outlet end 78 - 2 . The outlet end 78 - 2 may therefore be connected by suitable hose (not shown) to the inlet end 80 - 1 of a filter assembly 80 as shown in FIG. 8 so that the entrained particulates may be removed from the air flow through filter media 80 a. Substantially particulate-free air may therefore be discharged to the ambient environment from the filter assembly 80 through outlet 80 - 2 .
[0033] In use, the apparatus 10 is mounted above the furnace system 12 relative to the access opening 12 a (which may approximately be 8″×24″). The operator will manipulate the lance 50 so that the nozzle 52 is moved across the catalyst to be cleaned associated with the system component. As this happens, the soft graphite head of the nozzle 52 minimizes damage to the component while allowing close contact. The reduced pressure generated at the nozzle 52 sucks accumulated particulates from the component. These liberated particulates then travel along the lance 50 and hose 76 to the venturi device 78 and then into the main airflow through the venturi 78 to the filter media 80 a enclosed within the filter assembly 80 . The filter media 80 a collects and retains the dislodged particulates while the airflow through the filter 30 continues and is discharged into the ambient atmosphere through outlet 80 - 2 thereby avoiding atmospheric pollution from the particulates removed from the component.
[0034] Instead of cleaning a catalyst of an SCR system, the apparatus may be used to clean the convection section of a furnace. In this case, the graphite head of the nozzle may be replaced with a metal wire brush, as the heat transfer fins and pipes of the convection section are less prone to damage than the catalyst. While the same gantry and counterbalance can be used, in an alternative embodiment, the lance may be mounted on a balancing fulcrum, with the counterbalance mounted on an elongate rod on an opposing side of the balancing fulcrum. The lance, nozzle, reduced pressure generator, hose, and enclosed filter may be the same as described above. An access hole may be made in the convection section of the furnace to allow the lance and nozzle inside, to allow cleaning
[0035] An alternative embodiment of an apparatus 100 according to the invention is shown in FIGS. 9 and 10 . Specifically, the apparatus 100 will, like apparatus 10 described above include a gantry beam 102 connected to and spanning a pair of upright supports 104 , 106 . Similarly, the gantry beam 102 will likewise support the trolley 40 which in turn dependently supports the counterbalance device 42 having a tethering cable 42 a attached to a proximal end 50 a of the tubular vacuum lance 50 . The weight of the vacuum lance 50 is therefore counterbalanced by the counterbalance device 42 to allow an operator to insert the lance 50 into and remove it from the system being vacuum cleaned.
[0036] In the embodiment of the apparatus 100 depicted in FIG. 9 , the upright supports 104 , 106 include foot pads 104 a, 106 a which are positioned on a rigid supporting surface of the system being vacuum cleaned. In order to stabilize the gantry beam 102 spanning the upright supports 104 , 106 , a pair of stabilization assemblies 110 are provided. Each stabilization assembly includes at one end a U-shaped coupling member 112 which is sized and configured to be attached to a respective one of the upright supports 104 , 106 by means of retaining bolts 114 (see FIG. 10 ). A connection plate 116 is provided at an opposite end of the stabilization assembly 110 , the plate 116 having a raised lip bar 116 a so as to engage a flange of an existing structural support beam SB associated with the system being cleaned.
[0037] The U-shaped coupling member 112 and the connection plate 116 are respectively provided with threaded shafts 112 - 1 and 116 - 1 which are coaxially coupled to one another by a turnbuckle 120 . Thus, in thus the U-shaped coupling member 112 will be connected to one of the upright supports 104 , 106 and the lip bar 116 a of the connection plate 116 will be engaged with an edge of an adjacent one of the structural support beams SB. Thereafter, the turnbuckle 120 may be turned so as to drawn the U-shaped coupling member 112 and connection plate 116 toward one another. In such a manner, each stabilization assembly 110 will positively connect the upright supports 104 , 106 to an adjacent respective structural support beam SB thereby stabilizing the gantry beam 102 .
[0038] It will be understood that the description provided herein is presently considered to be the most practical and preferred embodiments of the invention. Thus, the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope thereof.
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Apparatus and methods are provided whereby a component can be cleaned while the furnace is operational. Additionally, particulates that have accumulated on the component can be collected and retained. The apparatus may include a portable frame, a tubular lance supported by the frame and having a nozzle at a distal end thereof, and a suction generator operatively connected to a proximal end of the lance to generate a suction at the nozzle. Manipulation of the lance to move the nozzle across a component allows accumulated particulates to be removed therefrom through the lance.
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[0001] This application is a continuation-in-part of Ser. No. 10/021/365.
TECHNICAL FIELD
[0002] This invention relates to inhibition of enzymes, especially to inhibition of microbial enzymes, and enzymes catalyzing development of neoplasms and metabolic dysfunctions, via interrelations of enzymes, ions, and ion exchanging compositions and/or ion adsorbents.
BACKGROUND OF THE INVENTION
[0003] As stated by Bohinski [1], in Modern Concepts in Biochemistry , “the totality of cellular activity is intimately dependent on the type and concentration of ionic materials within the cell, both of which are subject to change by alterations in the extracellular environment.” As stated by Dressler and Potter [2] in Discovering Enzymes , “Not to put too fine a point on it, enzymes control all of the chemical transformations in the living world.”
[0004] Enzyme-controlled reactions are essential to all phenomena of life. Nearly every cellular activity is catalyzed by enzymes, many of the enzymes dependent upon associated cofactors. Though differences between those cofactors may not be sharp-edged, Holum's proposition [3] lists three generally accepted categories of cofactors (also see a schematic thereof in FIG. 1 ), thus:
[0005] a) a coenzyme: a non-protein organic substance (e.g., a vitamin) dialyzable, thermostable, and loosely attached to an apoenzyme; a true substrate for enzyme-catalyzed reaction, recycled in a later step of a metabolic pathway by another enzyme;
[0006] b) a prosthetic group: a dialyzable and thermostable organic substance, firmly attached to the protein of the apoenzyme portion; and
[0007] c) a metal cation activator, metal cations being critical to enzyme function, structure, and stability.
[0008] In general, the more complex an organism, the more complex and numerous its enzymes, and the more likely it can survive some enzymatic irregularity, such as inadequate concentration, or absence of a given enzyme. Whereas metabolism in vertebrates depends upon a vast number of enzymes, whose activity may require presence of other enzymes, coenzymes, or similar cofactors, more primitive life forms (e.g., viruses, bacteria, protozoa, fungi) survive with fewer enzymes, often controlled only by an ion activator, and may have their metabolism or replication terminated by dysfunction of a single enzyme. The present invention views ions, which activate or otherwise control activity or stability enzymes as targets, with objectives to deactivate, inhibit, or destabilize enzymes, and thereby to neutralize pathogens, control development of neoplasms, and undesirable metabolic processes—with minimal collateral damage to their respective hosts.
[0009] Current methods of inhibiting microbial enzymes rely mostly upon activity of chemical agents; limited in degree upon such other means as heat treatment, radiation, immunization, hormone application, or genetic engineering. However, all of these approaches often have severe limitations and/or serious side effects. Researchers focus upon chemical enzyme inhibitors, usually antibiotics or other chemicals, administered to the host organism, and often causing eventual deleterious side effects. Some of them interfere with cell division, and often are toxic to both host and invader, while many of them may contribute to development of resistant mutation of targeted and/or non-targeted pathogens.
[0010] The present invention directs attention to adsorption of ions necessary for biocatalysis, via ion exchangers. Since the vast majority of enzymes, for practical purposes of present invention, are enzymes activated or otherwise controlled by cations, the main attention is directed to the enzyme inhibition by cation exchangers such as hydrous aluminosilicate compositions or synthetic cation exchangers, here exemplified specifically by zeolites. However, all processes and methods for inhibition of metalloenzymes, and for the preparation and modification of cation exchangers—as disclosed in this invention—are analogically applicable for inhibition of anion-dependent enzymes, and for the preparation and modification of anion exchangers, as well as organic ionexchanger such The more detailed disclosure of zeolitic inhibition of enzymes is presented by way of example rather than limitation.
[0011] Both natural and synthetic zeolites are well known as adsorbents, carriers and ion exchangers of ionic substances often intended to catalyze or to inhibit certain chemical activity. Sometimes zeolites are used, either solitary or distributed within an organic polymer, to convey a toxin, a chelate, or a heavy metal cation as a bactericide or fungicide, as in cosmetics and medicines. See, for example, Yoshimoto et al. U.S. Pat. No. 4,870,107 (1989); Hagiwara et al. U.S. Pat. No. 4,775,585 (1988), U.S. Pat. No. 4,911,898 (1990), U.S. Pat. No. 4,959,268 (1990), Satoshi et al. Japanese Patent Application 03218916 A (1991); Satoshi et al. Japanese Patent Application 03255010A (1991); Wagner U.S. Pat. No. 4,824,661 (1989); and Barry U.S. Pat. No. 6,365,130 B1 (2002). In Chu et al. U.S. Pat. No. 5,140,949 (1992), for example, a mixture of zeolite and clay is proposed as a feed supplement, and as a topical treatment, based on its ability to adsorb ammonium cations. Similarly, in Polak et al. U.S. Pat. No. 5,409,903 (1995), zeolite alone, or zeolite in a mixture of other chemicals, is proposed for the treatment of Helicobacter pylori and dermatitis. U.S. Food Additive Regulation 582-2727 approves zeolite use in feeds as an anti-caking agent, and USDA approves them in food processing applications; being in EPA compliance (40 CFR, Part 180.1001 and elsewhere). Engler U.S. Pat. No. 5,900,258 features silicates, de-aluminated but neither deionized nor homoionized, to inhibit microorganism growth on and within textile and other interstitial or porous materials, also on relatively impervious extensive structural or working surfaces, and in nutrient material fed to chickens in order to evaluate its possibility for reducing incidence of microorganisms in or arising from such feed. All of the foregoing efforts are of minor interest. Other specific uses of zeolites as carriers of substances harmful to biological, sometimes enzyme-dependent, activity also could be cited, but also are distinct from the present invention.
SUMMARY OF THE INVENTION
[0012] A primary object of the present invention is inhibition of enzymes, via adsorptive removal of their ions serving either as catalytic cofactors or as structural stabilizers or both, by ion exchangers.
[0013] Another object of the present invention is an adsorptive removal of ions from the immediate environment of targeted enzymes, thus preventing microbes and neoplasms from utilizing them for replenishment or for production of new enzymes.
[0014] A further object is to extend the present invention as a different approach to inhibition of enzymes in areas of medicine, cosmetics, dentistry, agriculture, and food processing.
[0015] One more object is to provide an alternative to antibiotics.
[0016] Yet another object of this invention is to inhibit any biotype, serotype or other induced or spontaneous mutation of microbes, including drug-resistant strains.
[0017] An additional object of the invention is to deactivate proteinaceous biotoxins (e.g., snake and insect toxins)—an objective that cannot be achieved by antibiotics.
[0018] Another object of this invention is to provide effective means of prophylaxis, to limit likelihood of infection from contaminated air, liquids, foodstuffs, bodily surface contact, etc.
[0019] A still further object is to accomplish the foregoing objects in an economically sound way and in a manner safe to the human organism.
[0020] In general, the objects of this invention are achieved by inhibiting activity of microbial and neoplastic enzymes, enzymes causing metabolic dysfunctions, and proteinaceous biotoxins, by supplying to the site of that activity an ion exchanger—for example a properly constituted aluminosilicate—effective to adsorb ions and related substances provocative of such undesirable biochemical activity.
[0021] By a synergic action, aluminosilicates appropriately selected, such as to density and size of pores, are adapted to serve as molecular sieves to bind entire specific molecules, e.g., toxins. This ability of suitable aluminosilicates is a practical expedient often resorted to in the substance-separation industries.
[0022] Alteration in relative affinities of natural zeolites for given monovalent and divalent cations, by dry heating pretreatment, and the benefits of doing so are disclosed in Taborsky U.S. Pat. Nos. 5,082,813; 5,162,276; and 5,304,365. Zeolites or equivalent compositions may be ion-pretreated, e.g., by deionization, or by homoionization, or may be synthesized in specific (e.g., hydrogen) cation form, and be applied as a broad-range adsorbent, or may be selectively reionized for specific applications. Equivalent compositions may be combined for complementary and/or synergic purposes and/or for their affinities for ions or classes thereof.
[0023] Other objects of the present invention, together with means and methods for attaining the various objects, will become readily apparent from the following description, presented by way of example rather than limitation.
SUMMARY OF THE DRAWINGS
[0024] FIG. 1 comprises three schematized representations of a complete enzyme, comprising an apoenzyme (A) in separate conjunction with each of several different cofactors: (a, b, c).
[0025] FIG. 2 is a schematized representation of a zeolite (Z), in conjunction with each of a zinc activated protease (DP) and a tripartite toxin (LF+OF+PA) as in a digestive enzyme.
DESCRIPTION OF THE INVENTION
[0026] The invention is characterized in practical terms, so as to enable its successful practice, regardless of any academic or theoretical conceptualization expressed in this exposition thereof, as concurrence in the latter is not a prerequisite for successful practice of the actual invention.
[0027] Whereas “ionization” generally means a process of producing ions, in this description “ionization” and its inflected forms (e.g., reionization, homoionization) have the meaning of charging or loading an ion exchanger with ions—as a logical opposite of the unambiguous term “deionization” (being a conventional term for removing ions). The term “adsorbent” means an ionexchanger with most of its ion exchangeable sites unoccupied.
[0028] For all practical purposes, principles and methods of enzyme inhibition of bacteria, viruses, neoplasms, and metabolic dysfunctions via adsorption of their activating, stabilizing, or otherwise controlling ions by ion exchangers are identical. However, for demonstration of such inhibition bacteria are most suitable, as in the instant example of bacteria of the Bacillus anthracis group.
[0000] Preliminary Testing of inhibition of enzyme activity by zeolitic adsorption was conducted using the accepted ninhydrin (1,2,3-triketohydrindene hydrate) test for presence of amino acids from enzymatic breakdown of casein.
[0029] 1. At room temperature, 100 mg of bacterial protease was stirred into 100 ml of distilled water containing 10 g of deionized (method 2Bd) clinoptilolite particles (<74 μm). After about 10 minutes of mild agitation, 10 ml of this solution was stirred thoroughly into 50 ml of 5% DIFCO isoelectric casein solution, which tested negatively as to free amino acids an hour thereafter. This test indicated that the bacterial protease was deactivated, or the activating and/or stabilizing cations were depleted from the casein solution, or both.
[0030] 2. To avoid possible confusion by an eventual interaction between casein and zeolite, the test was modified as follows: at room temperature, 100 mg of bacterial protease was stirred into 100 ml distilled water containing 10 g of deionized (method 2Bd) clinoptilolite particles (300>600 μm). After about 10 minutes of mild agitation, the suspension was filtered through a 200 μm nylon sieve, then 10 ml of the filtrate was stirred thoroughly into 50 ml of 5% DIFCO isoelectric casein solution, which then tested negatively for free amino acids an hour thereafter. This result indicated that the bacterial protease was deactivated.
[0031] 3. Test 2 was then conducted in a more refined process by circulation of the therein specified solution in 10× larger volume through a bed of clinoptilolite particles (300>600 μm). It should be noted that some enzyme species are able to replenish their needed ions from their environment within some limited time after deactivation, and therefore, the time lapse before inoculation should be adjusted accordingly.
[0032] The zeolite adsorbed cations from the enzyme and inhibited it from breaking the casein down and providing amino acids for detection. Similar tests were conducted with different species of zeolite (phillipsite, chabazite), with deionized and H + homoionized samples from different sources, and with synthetic zeolites (Y, Beta, and ZMS-5 powders), and all test results indicated inhibition of the protease.
[0033] Further analogous tests indicated that all previously used deionized and H + homoionized natural and synthetic zeolites inhibited all tested bacteria, but tests with virgin natural zeolites were not entirely conclusive, suggesting a need for pretesting of each batch thereof, or for limiting actual operations to use of aluminosilicates pretreated as specified here, operative both in vitro and in vivo, such as for agriculture, dentistry, medicine, and biological instances generally.
[0034] Analogous tests to inhibit the (Cl − ) anion-activated α-amylase by an anion exchanger (resin A-SIP OH) indicated positive results. However, a cation exchanger can achieve the inhibition of the same enzyme also via adsorption of Ca ++ , which is necessary for stability of α-amylase.
[0000] Selection, Modification, and Applicability of Aluminosilicates.
[0035] The aluminosilicates, especially zeolites are customarily used as ion exchange media, in effecting separation and recovery of dissolved materials, liquids and gases, as carriers of ions. and specifically as molecular sieves (e.g. for cracking petroleum fractions). Aluminosilicate minerals occur in many geographical locations and include prominently zeolites: clinoptilolite, chabazite, phillipsite, analcite, brewsterite, faujasite, ferrierite, flakite, gmelinite, leucite, stilbite, and yugawaralite; also the layer (or pseudo-layer) silicates, vermiculites and smectites—often called layered clays; bentonites, and kaolinites.
[0036] The foregoing natural minerals are hydrated mixed aluminosilicates, with compositions determined largely by the constituents available when they were formed, resulting in diverse crystalline structures. Synthetic zeolites have been produced with more controlled compositions, and often are designated by a letter (e.g., “F”, “X”) appended to “zeolite.”Whether produced under laboratory conditions or in mineral deposits, these ion exchangers range widely in composition and physical properties. Their identification, as well as their properties, can vary, depending upon specific interesting characteristics—here, their physical properties, modification and manipulation of accessible surfaces and sites for adsorption of cations.
[0037] Ion exchangeable aluminosilicates have a distinctive molecular arrangement causing a negative charge of their molecules. It results in strong adsorptive power, unmatched by any other adsorbent and strong enough to penetrate the protective coats of vegetative forms of microbes, and moist-swollen exosporia, and protective coats of endospores. A similar transfer of cations through gels has been well demonstrated (see section 7B below: Application of aluminosilicate enzyme inhibitor). Aluminosilicates form extremely porous crystalline structure having tiny uniform pores, measuring in some species only a few Å, and endowing them with tremendous interior surface area having numerous ion exchangeable sites. Their negative charge enables these sites attract, adsorb, and eventually exchange, cations.
[0038] Consequently, aluminosilicates possess a unique ability to adsorb metallic activators of enzymes controlling biochemical processes in viruses, bacteria and some other low-organized organisms. Natural aluminosilicates, synthetic zeolites and other ion exchangers were tested in practicing and evaluating this invention.
[0039] Natural aluminosilicates or synthesized zeolites, when properly selected and modified, are, for all practical purposes, chemically inert and do not cause any chemical side effect to the host organism. They are not recognized by the pathogen or by the host as xenobiotics. Therefore, they are unlikely to trigger any immunologic reaction in the host or to activate any defense mechanism of the pathogen. Hence, the pathogens are unlikely to develop any resistance to the loss of enzyme activator, as in the practice of the present invention.
[0040] As therapeutics and prophylactics, aluminosilicates work in three principal ways, without any appreciable toxic or biochemical impact on the host organism:
[0041] a) inhibiting activity of microbial and neoplastic metalloenzymes;
[0042] (b) deactivating toxins; and
[0043] (c) adsorbing cations from immediate microenvironments, thus preventing microbes and neoplasms from utilizing them for replenishment or for production of new metalloenzymes.
[0044] (d) in synergic effect as microbial enzyme inhibitors and desiccants, they are extremely useful in dermatology for topical therapy of wet wounds, blisters, non-healing wounds, ulcers, eczemas, skin cancers, herpes blistering, etc.
[0045] Virgin aluminosilicates exhibit substantial differences in chemical composition, crystalline structure, density, and levels of impurities. Aluminosilicates of high density, aluminosilicates with a considerable crystalline silica contamination, fibrous aluminosilicates, and aluminosilicates contaminated with specific cations, and the like, are unsuitable for medical or pharmaceutical purposes. Accordingly, deionized, homoionized, selectively ion-recharged, or otherwise modified natural aluminosilicates and synthetic zeolites are preferable to virgin aluminosilicates in the practice of this invention.
[0000] 1. Typical Ion Exchangers Used in Experiments:
[0046] A. Natural zeolite: clinoptilolite, hydrated sodium potassium calcium aluminum silicate (Na, K, Ca)2O.Al 2 O 3 .10SiO 2 .8H 2 O), Winston, N.M. deposit, 4×6 size granules (approx. 5 mm).
[0047] Analysis (weight % for major oxides): Bowie and Barker, NM Bureau of Mines, 1986): Silicate 64.7%, CaO 3.3%, MnO 0.1%, Al 2 O 3 12.6%, MgO 1.0%, TiO 2 0.2%, K 2 0 3.3%, Fe 2 O 3 1.8%, and Na 2 0 0.9%.
[0048] Chemical Composition for given elements, by x-ray fluorescence (ppm, or wt. % noted; by Desborough, USGS OF Rpt 96-065 & 265, 1996.):
K 2.0% Cu 30 Zr 190 Nd 15 Ca 2.7% Fe 0.9% Rb 70 Nb 20 Ba 1030 Sr 1720 Ce 90 Pb 40
[0049] Cation Exchange Capacity:
[0000] 1.00-2.20 meq/g (may vary, as CEC values are relative to procedure and specific cations).
[0050] Major Exchangeable Cations: Rb, Li, K, Cs, NH4, Na, Ag, Ca, Cd, Pb, Zn, Ba, Sr, Cu, Hg, Mg, Fe, Co, Al, Cr, Mn, H.
[0000] (Selectivity of such cations is a function of hydrated molecular size and relative concentrations).
[0051] Purity:
[0052] Analysis by x-ray diffraction at the N. M. Institute of Mining and Technology and other tests suggest an 80% clinoptilolite content with the remaining material primarily inert volcanic ash and sediments. Clay and other mineral varieties are detectable only in minute quantities.
[0053] Physical Properties:
pH (natural) 8.0 (approx.) Acid Stability 0-7 pH Alkali Stability 7-13 pH Bulk Density (dried, −40 Mesh) 783-1054 kg/m 3 Cation Exchange Capacity (CEC) 1.0-2.2 meq/g Color White (85 optical reflectance) Crushing Strength 2500 lbs/in 3 (176 kg/m 3 ) Hardness 3.5-4.0 Mohs LA Wear (Abrasion index) 24 Mole Ratio 5.1 (SiO 2 /Al 2 O 3 ) Other non-soluble, non-slaking, free flowing Pore Size (diameter) 4.0 Å Pore Volume 52% (max.) Resistivity 9,000 (approx.) ohms/cm Specific Gravity 2.2-2.4 Surface Area 1357 yd 2 /oz (40 m 2 /g) Swelling index 0 Thermal Stability 1202° F. (650° C.)
[0054] B. Synthetic zeolite: Zeolyst® Y Type zeolite powder (FAU) CBV 400 in cation form.
Molecular Ratio 5.1 (SiO 2 /Al 2 O 3 ) Unit Cell Size 24.50 Å Surface area 730 m 2 /g
[0055] C. Bead Cellulose: Perloza® MT 50, a macroporous gel bead cellulose, stabilized by 25% ethanol.
Particle size 100-250 μm Temp. resistance (wet/pH 7.0/1 hr) 120° C. Stability within pH range 1-14 Stability in salt solutions with ionic strength up to 10 mol/l Chemical resistance aqueous solutions, buffer, organics, detergents, and chaotropic agents Swelling in aqueous solutions max 1 vol %
[0056] For purposes of this invention, the suitability of bead cellulose and its derivates is limited. They must withstand a wet stage, because the process of desiccation severely damages their porosity.
[0057] D. Anion exchanger: Anion Resin in Hydroxyl Form (A-S1P OH)
[0000] 2. Modification of Aluminosilicate Cation Exchangers:
[0058] A. H + Homoionization:
[0059] a. H + Homoionization Via Ammonia Decomposition:
[0060] The aluminosilicate is first impregnated by ammonium cations to displace the achievable maximum of other cations via ion exchange, then washed, dried, and finally heated to 500° C. At this temperature, ammonium decomposes to gaseous ammonia, which escapes, and hydrogen cations, which occupy available adsorption sites of the aluminosilicate. The thermal stability of treated aluminosilicate species and types must be considered unless a distortion of crystalline structure is negligible for the given application, or if a certain distortion of the crystalline structure is desirable as an additional functional modification.
[0061] b. H + Homoionization Via Electrolysis of Water:
[0062] A stream of hydrogen cations generated by electrolysis of water is directed through a bed, preferably a fluid bed, of sand or granule-sized aluminosilicate. Via ion exchange, an achievable maximum of other cations on ion exchangeable sites is replaced by hydrogen cations. The excess of hydrogen cations is reduced on the cathode to hydrogen gas. The cathode should be placed in a trapping device that collects reduction products and positively charged impurities. While this is an elegant and very pure method, an eventually insufficient concentration of electrolyte may render the H + homoionization imperfect. However, this is the only practical method of H + homoionization of hydrocolloid aluminosilicates.
[0063] The performance of the process may be improved by a modification of the electrolytic apparatus, provided by rotating chambers, by rotating phases of polarity, and/or by enhancing the electrolyte with ionized effluent water from one (or more) auxiliary electrolyzer(s). Such modified electrolytic apparatus also may be applied advantageously for ionization, homoionization, or reionization processes described later.
[0000] c. H + Homoionization Via Acid Treatment:
[0064] Most acids are suitable, but inorganic acids are preferable, especially nitric acid because of easy and environmentally sound disposal of NO 3 − anion effluent. However, for purposes of some special cation exchanger's selectivity, the use of organic acids must be considered. Adsorbent of sand or granule size is treated with diluted (e.g., 3%) acid in order to displace the achievable maximum of other cations by hydrogen cations via ion exchange, then rinsed with redistilled or medical grade deionized water to remove formed salts and anions to an achievable minimum.
[0065] Unless a synergic low pH effect is sought, the pH of H + homoionized adsorbents should be adjusted by washing with redistilled or medical grade deionized water, or by OH − treatment to establish the desirable pH value.
[0066] B. Deionization:
[0067] a. Partial:
[0068] The adsorbent is washed with redistilled or medical grade deionized water until most ion exchangeable sites are, by equilibration, free of cations. For achieving high degree of deionization, this method is too time consuming and economically unfeasible.
[0069] b. By Water Electrolysis:
[0070] A bed, preferably a fluid bed, of adsorbent is first electrolytically H + homoionized (method 2Ab), rinsed, and then the polarity of electrodes is reversed, whereby the aluminosilicate bed is exposed to a stream of hydroxyl anions (OH − ) until the desired pH is stabilized.
[0071] c. By a Combination Method:
[0072] A bed, preferably a fluid bed, of adsorbent, already H + homoionized (method 2Aa, 2Ac) is exposed to a stream of hydroxyl anions (OH − ) until the desired pH is stabilized.
[0073] d. By (OH − ) Effluent from an Anion Exchanger:
[0074] A bed, preferably a fluid bed, of H + homoionized adsorbent is exposed to an OH − water effluent generated by an anion exchanger until the achievable maximum of hydrogen cations has been removed from the aluminosilicate (or until a desired pH is established), via formation of water during the process of equilibration.
[0075] C. Selective Ionization:
[0076] For specific purposes (e.g., to prevent or to mitigate adsorption of selected cations, such as calcium or iron cations, or to deliver to the site cations for specific purposes (e.g., copper or cobalt ions), adsorbents may be ionized with any selected metal cation or cations via appropriate salts or hydroxides. A selective ionization may be implemented during or immediately after homoionization, or instead of homoionization. The following methods are preferred in the practice of this invention.
[0077] a. Selective Reionization by Cations Toxic to Microbes or Neoplastic Growth:
[0078] Using untreated (virgin) zeolite as a carrier of toxic cations to function at a destination site is known. However, for medical purposes the prior art is generally unsuitable because the concentration of such toxic cations in virgin aluminosilicate is difficult to establish and maintain because of uncontrollable factors, such as impurities, present unavoidable cations, pH fluctuation and consequent fluctuation of toxicity level, and equilibria in the microenvironment and within the aluminosilicate. In many applications accuracy in the cation concentration is critical. For example, excessive concentrations of copper cations will mitigate or completely inhibit production of mucous surfactant, which protects the host's gas-exchanging cells [4][5], and thereby may cause irreversible damage to a host's respiratory system and eventually result in death of the host. The methods of pretreatment of aluminosilicates as disclosed in this application, especially in applications of deionized aluminosilicates, allow appropriate accuracy of the dosage of toxic cations, thereby protecting the host's tissues, and equalizing any eventual site competition.
[0079] b. Selective Ionization of Adsorbent by Auxiliary Cations
[0080] This is of special interest. For example, one of the severe symptoms of inhalational anthrax is shortness of breath. It is caused (besides the bacterial damage to the alveolar epithelium) by the consumption of zinc ions by anthrax bacilli. Zinc cation is the primary activator of carbon anhydrase—the enzyme catalyzing the reversible hydration of CO 2 to H 2 CO 3 , a necessary reaction for facilitation of transport of CO 2 , and transfer and accumulation of H + and HCO 3 − . Hence, the deficiency of zinc cations contributes substantially to the inhibition of the respiratory gas exchange process. However, some carbon anhydrases are able to function with an alternative metal activator, as with the cobalt cation in this instance [19], and possibly with other metal cations, e.g., cadmium. Ion-exchanger adsorbing zinc activators from bacteria, from their immediate microenvironment, and from their toxins, can serve simultaneously as carriers of cobalt cations to boost the carbon anhydrase catalytic activity, and thereby greatly mitigate the “short breath” symptoms. The cobalt cations may be administered via an ion-exchangeable carrier, or as a part of a compound (e.g., salt or chelate) in any suitable therapeutic form (e.g., aerosol, hydrosol, intravenous infusion, or extracorporeal filtration of bodily fluids through a bed of cobalt-impregnated ionexchanger).
[0000] 3. Life Forms Used for Testing of Enzyme Inhibition; Experiments, Observations, and Evaluations:
[0081] A. Bacteria of the Bacillus anthracis Group:
[0082] Within the genus taxon, the current taxonomic and nomenclatural rules do not recognize any “group” taxon—which is only ancillary, indicating a close systematic and phylogenetic relation of certain species, here those of B. anthracis , namely: B. cereus, B. mycoides and B. thuringiensis . This group is frequently informally designated as the Bacillus cereus group. See, Genus Bacillus Cohn 1872. Hierarchy: Monera Bacteria-Inside series of Bacteria-Bacillales. Nomenclatorial/taxonomic status: Approved Lists Type species: B. subtilis Reference(s): Int. J. Syst. Bacteriol. 30:256 (AL), (Bergey's manual of determinative Bacteriology, 8th ed., 1974; Editors: Buchanan, R. E., Gibbons, N. E; Publisher: The Williams & Wilkins Co., Baltimore).
[0083] The B. anthracis group is a group of closely related species within the genus Bacillus . Though classified as valid different species, these organisms seem to differ only in the plasmids. All four species are large straight rod-shaped Gram-positive, non-flagellated, endospore-producing bacteria, whose spores do not swell the sporangium. They are often aerobic cells of 1-10 μm in length, and 1-1.5 μm in breadth, with a “jointed bamboo-rod” cellular appearance. All species of the B. anthracis group are pathogenic to humans, causing known or potential cutaneous/subcutaneous, intestinal, inhalational and other infectious conditions. The endospores are approximately 1 μm, species-indistinguishable within the group. Endospores are extremely resistant and may survive, for entire geological periods, at temperatures ranging from absolute zero to −40° C., and for decades between −30° C. and at least 50° C. They can withstand several minutes of usual autoclave sterilization and at least one minute of usual microwave sterilization. They germinate readily, and their vegetative cells grow on all ordinary laboratory media, at like temperatures and times, except that B. anthracis prefers a range closely about 37° C. Bacteria of the B. anthracis group share a multitude of other characteristics, including both biochemical and biophysical properties. Differentiation of the respective organisms is done in the vegetative form by determination of motility ( B. cereus rods are usually motile), and by the presence of toxin crystals ( B. thuringiensis ), and also by hemolytic activity ( B. cereus and B. thuringiensis are beta-hemolytic, B. anthracis is usually non-hemolytic), by growth requirement for thiamin, by lysis via gamma phage, by growth on chloral-hydrate agar, and further by the morphology of micro-colonies (e.g., a rhizoid growth is characteristic for B. mycoides , and a perloid growth pattern for B. anthracis ).
[0084] A. Bacillus anthracis (Cohn 1900), various synonyms: Bacillus cereus var. anthracis (Cohn 1872); Smith et al. 1946 ; Bacteridium anthracis (Cohn 1872); Hauduroy et al. 1953. Nomenclatorial/taxonomic status: Approved Lists Reference(s): Int. J. Syst. Bacteriol. 30:256 21 (AL), Ref.: Bergey's manual of determinative Bacteriology, 8th ed., 1974; Editors: Buchanan, R. 22 E., Gibbons, N. E; Publisher: The Williams & Wilkins Co., Baltimore); Risk group: 3 (German 23 classification) Type strain: ATCC 14578. Bacterial proteolytic enzyme: Zn + activated protease; 24 LF of the tripartite toxin: specific Zn ++ activated protease; OF: adenylate cyclase.
[0085] Bacillus anthracis is usually an aerobic, nonmotile species. The vegetative cells are large rods (1-8 μm long, 1-1.5 μm wide). B. anthracis is the causative agent of the anthrax disease. The symptoms of all three forms (cutaneous, intestinal, and inhalational) are well known [15]. Anthrax has been intended to be the most dangerous biological warfare agents for more than eighty years. Within that time, countless deadly strains have been developed, many of them as antibiotic-resistant and drug-resistant strains. Neither trials nor any cultivation of B. anthracis were conducted for purposes of this invention, but experimentation on other of the members of the group has been undertaken successfully and tentatively is believed to be applicable to every B. anthracis group member, based upon their close phylogenetic relationship.
[0086] B. Bacillus cereus (Frankland & Frankland 1887) ambiguous synonym(s): Bacillus cereus var. anthracis, Bacillus thuringiensis, Bacillus endorhythmos, Bacillus medusa . Nomenclatorial/taxonomic status: Approved Lists Reference(s): Int. J. Syst. Bacteriol. 30:256 (AL), (Ref: Bergey's manual of determinative Bacteriology, 8th ed., 1974; Editors: Buchanan, R. E., Gibbons, N. E; Publisher: The Williams & Wilkins Co., Baltimore); Risk group: 2 (German classification) Type strain: ATCC 14579, CCM 2010, NCm 9373, NCTC 2599. Bacterial proteolytic enzyme: Zn ++ activated protease; LF of the tripartite toxin: specific Zn activated protease; OF: adenylate cyclase. Intestinal infection, causing food poisoning, has been believed for a long time to be the only medical concern. The symptoms of the diarrhea type of food poisoning mimic those of Clostridium perfringens , beginning with watery diarrhea, sometimes accompanied by nausea and vomiting. Abdominal pain and cramps occur 6-15 hours after infection. Usually such symptoms persist for 24 hours. Symptoms of the emetic type are similar to those of Staphylococcus aureus : nausea and vomiting within 30 minutes to 6 hours after consumption of contaminated food. Abdominal cramps and diarrhea may occur too. Symptoms generally last less than 24 hours.
[0087] Recently, however, cutaneous B. cereus infections causing acute necrosis very similar to the cutaneous form of anthrax have been reported. Even more dangerously, several cases of B. cereus infections of other tissues occurred: including rapidly fatal meningoencephalitis [14], septicemia, mastitis, and several cases of potentially blinding endophthalmitis [6][7].
[0088] Since B. cereus is a typical airborne-spore proliferater, and sporulates and germinates easily, it is a potential agent for inhalation infections. No verified case of an inhalational form of infection has been reported yet. It may be hypothesized that B. cereus OF enzyme did not mutate yet—as B. anthracis did—to be effective enough to impair the host's defense system. Inocula: Bacillus cereus strain CBSC 15-4870/2001, freeze-dried CBSC 15-4870A/2001.
[0089] C. Bacillus mycoides (Fluegge 1886), ambiguous synonym: Bacillus mycoides corallinus. Hefferan 1904. Nomenclatural/taxonomic status: Approved Lists Reference(s): Int. J. Syst. Bacteriol. 30:257 (AL), (Ref.: Bergey's manual of determinative Bacteriology, eighth ed., 1974. Editors: Buchanan, R. E., Gibbons, N. E; Publisher: The Williams & Wilkins Co., Baltimore; Die Mikroorganismen, 3rd ed. vol. 2, 1896; Editor: Fliigge, C.; Publisher Vogel, Leipzig); Risk group: 1 (German classification); Type strain: ATCC 6A62. Bacillus mycoides is in almost all of its characteristics like B. cereus —but for its morphological rhizoid pattern of micro colonies. Bacterial proteolytic enzyme: Zn ++ activated protease; LF of tripartite toxin: specific Zn ++ activated protease; OF: adenylate cyclase. Inoculum: B. mycoides strain CBSC 15-4870/2001.
[0090] D. Bacillus thuringiensis (Berliner 191+5) ambiguous synonym: Bacillus cereus var. thuringiensis (Berliner 1915) ambiguous synonym: Bacillus cereus var, thuringiensis (Smith et al. 1952). Nomenclatural/taxonomic status: Approved Lists Reference(s): Int. J. Syst. Bacteriol. 30:258 (AL) (Ref.: Bergey's manual of determinative Bacteriology, 8th ed., 1974; Editors: Buchanan, R. E., Gibbons; N. E; Publisher: The Williams & Wilkins Co., Baltimore); Risk group: 1 (German classification); Type strain: ATCC 10792, Sp2000 Taxon Code: BIO-6867. Bacterial proteolytic enzyme: Zn ++ activated protease; LF of the toxin: specific Zn ++ activated protease; OF: adenylate cyclase.
[0091] B. thuringiensis is a bacterium, marketed worldwide as a specifically targeting bioinsecticide for control of plant pests (mainly caterpillars of the Lepidoptera), for control of mosquito larvae, simuliid blackflies, etc. Genetic material from B. thuringiensis toxin is used in the development of genetically engineered corn, cotton, and other crop plants. Most BT insecticides are derived from genetically improved mutations of B. thuringiensis biovar israelensis or B. thuringiensis kurstald. The active ingredients of marketed BT products are the bacterial dormant spores (>1012 per liter) and proteinaceous aggregates, including crystal-like parasporal inclusion bodies (PIB). The research done for manufacturers of BT products presents the bacterium as safe to human health. Yet, much as may be indicated, for example in DiPel®DF MSDS [16], the trials appear purpose-designed. In general, the health implications of exposures to B. thuringiensis , especially inhalational effects, have not been yet satisfactorily investigated.
[0092] Because of the close phylogenetic relation between B. anthracis group species, it should be taken into consideration that a dose of Bt spores, sufficiently potent to cause an inhalational Bt infection, may cause an infection with symptoms mimicking the symptoms of an anthrax infection (in at least one test, the mortality in guinea pigs was 10% [10]).
[0093] The BT products generate nonspecific cytotoxicities involving loss in bioreduction, cell rounding, blebbing and detachment, degradation of immuno-detectable proteins, and cytolysis. Some research data indicate that spore-containing BT products have an inherent capacity to lyse human cells in free and interactive forms and may also act as immune sanitizers [17]. Inocula used: Bacillus thuringiensis strain CBSC 15-4870/2001 (vegetative cells), CBSC 154870A/2001 (lyophilized vegetative cells), Javelin® (endospores, strain not identified), Thuricide® (endospores, strain not identified), and Skeetal® Abate (endospores, strain not identified).
[0094] Classified in the Bacillus anthracis group may be a newly described species Bacillus pseudomycoides but there has not yet been sufficient research done to validate it.
[0095] Bacillus pseudomycoides Nakamura 1998 Reference(s): BIO-6840, Nakamura (L.K.): Bacillus pseudomycoides sp. nov., Int. J. Syst. Bacteriol., 1998, 48, 1031-1035. No trial nor any cultivation of B. pseudomycoides has been conducted for the purposes of this invention. Many characteristics of B. anthracis, B. cereus, B. mycoides and B. thuringiensis are alike. For this invention the most important trait is that the bacterial metabolic protease and the lethal factor (LF) of the toxin are zinc-dependent; that is, the enzymes are activated by the zinc cation [8]][9][19][11][12][13]. Thus, it can be assumed with reasonable certainty that the mechanism of inhibition of their metabolic proteases and the deactivation of their toxin enzymes by adsorptive removal is similar in all four species, especially in B. cereus and B. anthracis , being so clearly alike in so many regards.
[0000] 4. Culture Media
[0096] A multitude of suitable media for culturing Gram + bacteria has been tried, including standard beef bouillon, nutrient gelatins and broths, count agar, modified nutrient agar (without peptone), protein-enriched nutrient agar, TSA w/5% and 10% sheep blood, etc. All of the media tested supported growth of vegetative cells and germination of endospores (where applied) along with the expected unimportant differences in morphological patterns of micro-colonies. After preliminary testing for suitable uniform media, a T-011 modified nutrient agar was chosen, consisting of standard beef extract, 5 g; agar, 15 g; with rehydration, 23 g/1000 ml. At its pH of 6.8, this agar is well within the optimal range for the Bacillus anthracis group.
[0000] 5. Inoculation of Bacteria
[0097] Many inoculation methods were tried in preliminary assays, including direct swab smear, diluted smears, loop inoculations in varied cell concentrations, smears and loops of inocula diluted in redistilled water, as well as smear and loop inocula diluted in physiol. solution. Dry inoculates of spores were tried also (where applicable). In all trials, the temperature was maintained at approx. 25° C. All of these experimental methods proved satisfactory. After these preliminary trials, two specific methods were selected for formal experimentation, as follows:
[0098] A: a swab smear inoculum from an established culture, diluted in redistilled water in a 1:10 approx. wt. ratio (cell:water). Cell count was not done. A long, single smear was applied.
[0099] B: 0.5 ml of diluted inoculum just described above (5A) was spot-dropped in the center. Note: Dry spore inoculation was abandoned in the final trials because the resulting rapidity of germination would have required needlessly difficult measurement of very small time intervals.
[0000] 6. Actual Experimental Results
[0100] The results in all trials proved positive, as expected in view of the preliminary trials. There were expected differences in vigor of the growths, in morphological patterns of micro-colonies, plus some aberrations from standard phenotype, but none pertinent to this invention. The following findings have been clearly established: A. the ionized zeolite inhibits Zn ++ activated bacterial proteases; and B. the inhibition is substantially instantaneous.
[0000] 7. Application of Aluminosilicate Enzyme Inhibitor
[0101] In some preliminary trials, the inhibitor was applied after a growth of micro-colonies was apparent under 10× magnification. This method was abandoned after it was well established that the inhibitor has an instant effect. Such instant effect is illustrated in FIG. 2 . Also in some trials with fluid media, a similar delay in inhibitor application was adopted.
[0102] A. For the inoculation method 5A, pH 6.4 stabilized deionized clinoptilolite particles of mesh 200 (<74 μm) were applied onto one half of the plate (the other half serves as a control) immediately after inoculation: a. as a dust, and b. as a hydrosol.
[0103] B. For inoculation method SA, pH 6.4 stabilized and deionized clinoptilolite particles of mesh 200 (<74 μm) were applied saturated in pieces of an inert porous absorptive material (filter paper) on the margin of the plate.
[0104] Note: In some preliminary runs, a bicomposite medium was also tried, by pouring one half of the plate in the original formulation, and the other half incorporating aluminosilicate inhibitor. Smearing inoculum over both halves of the plate, made the inhibitor effect immediately apparent.
[0105] The latter alternative also proved the tremendous adsorptive power of aluminosilicates to transfer ions through gel substances, as for example mucus, covering GEC's (gas-exchanging cells) in alveoli and elsewhere, or even more importantly, the protective coats of microbes.
[0000] 8. Detailed Description of Drawing Figures
[0106] FIG. 1 : Enzyme cofactors according to Holum
[0107] A complete enzyme (holoenzyme) consists of an apoenzyme (A) and one or more cofactors of the following three types: a, b, and c.
[0108] a. Coenzyme, a non-protein organic substance (e.g., a vitamin) which is dialyzable, thermostable, and loosely attached (single vertical connecting line) to the apoenzyme. It is a true substrate for enzyme-catalyzed reaction, and is recycled in a later step of a metabolic pathway by another enzyme.
[0109] b. Prosthetic group, a dialyzable and thermostable organic substance. It is more firmly attached (multiple linking vertical connecting lines) to the protein of the apoenzyme portion. Metal activator, a loosely attached metal cation, e.g., Zn ++ , K + , Fe ++ , Ca ++ , Mg ++ , Co ++ , Cu ++ , or Mn ++ . The metal cations are critical to the enzyme function, structure, and/or stability, and they ultimately are .of great biological and medical importance.
[0110] FIG. 2 : Adsorption of enzyme activator via zeolite (H + concentration ˜10 −7 )
[0111] Hydrogen cations (H + ) occupying some ion exchangeable sites (S) on the exosurfaces and endosurfaces of zeolite Z are in equilibrium with H + cations of the surrounding environment. When a bacterial digestive enzyme, a zinc-activated protease (DP), or a tripartite toxin (comprising zinc-dependent lethal factor LF, plus oedema factor OF (an adenyl cyclase), plus four-domain protein PA, enters the adsorptive range of such a zeolite particle, zinc cations Zn ++ will be adsorbed, immediately inhibiting the bacterium and deactivating the toxin. Also deactivated will be toxins already excreted by the pathogens into the host's macroenvironment (e.g., epithelium of alveoli, or bodily fluids.)
[0112] The drawing area designated Z represents only a minuscule part of the adsorptive surface of a zeolite particle, with interconnecting porous crystalline structure. The small size of most aluminosilicate pores (e.g., 4 Å, in the clinoptilolite example herein) precludes entry of pathogens or their proteins (e.g., bacterial digestive proteins, or toxins), whereupon rapid adsorption occurs on the outer surface, and (upon reaching equilibria there) thereafter proceeds within the particle of the ion exchanger.
[0000] 9. Mode of Inhibition
[0113] The negatively charged ion exchanger attracts and adsorbs the cation activators of enzymes [ FIG. 2 ] which renders the enzymes (the bacterial digesting protease and toxin's LF protease) deactivated.
[0000] 10. Practical Applications of Adsorbents:
[0114] In all applications, the ion adsorption is enhanced greatly in a wet environment. In a dry environment, e.g., on skin, inhibitor should be applied wet and be maintained wet (however, see 10.A.a.) For therapy of cutaneous and intestinal infections, the use of suitable aluminosilicates is entirely safe. For inhalational infection therapy, and in applications involving the circulatory system, a number of side effects of mechanical and biophysical nature should be considered.
[0115] A. Cutaneous infection and neoplasia: the adsorbent may be applied topically, as follows:
[0116] a. Dry: applicable in powder form directly to provide a synergic desiccating effect for wet or watery wounds, blisters, burns, herpes lesions, ulcers, bleeding wounds, etc.
[0117] b. Wet: for cutaneous infections and neoplasms not acutely wet, the adsorbent should be used preferably wet—mixed with clean water, preferably distilled water, and applied as a spray or a thin paste; incorporated in an inert gel; as a gel-like mixture with powdered hydrated layered clays, or in dressings or bandages impregnated with ion exchanging inhibitor.
[0000] B. Intestinal infection May be Treated, as Follows:
[0118] a. By ion adsorbent administered orally, preferably before a meal, mixed in a drink (water, milk, tea) devoid of any salt preservative. USDA approved addition of zeolite in feed is very conservative at 2%. A substantially higher dose (more than 5 times the approved rate) may cause a temporary depletion of intestinal flora. Particle size of the ion adsorbing inhibitor is not critical; 200 mesh (approx. 75 μm) being good. Of course, the smaller the particles are, the faster the adsorption process will be. Ion adsorbing inhibitor passing through the digestive system deactivates bacteria, viruses, protozoan, certain worms, toxins, and digestive metalloenzymes; then it is excreted.
[0119] b. Following ingestion, the adsorbent is at least partially H + homoionized by the stomach acid, and then gradually stabilized to the equilibrium in the small intestine.
[0120] C. Inhalational Infection
[0121] Preparation of dry aluminosilicates in the very small particle size (<3 μm) necessary to reach the inner epithelium of alveoli is technically difficult. The most practical mode of administration is inhalation of a mist containing submicron particles, easily calibratable by sedimentation in a water column. Insofar as there is a concern about clogging of alveoli, as caused by an eventual extremely large overdose, even a complete coverage of the alveolar epithelium by adsorbent's particles delivered via aerosol (or hydrosol) of suitable composition (e.g., containing surfactant) would not inhibit in appreciable extent the functioning of the epithelium. The adsorbent's capacity for CO 2 adsorption is negligible, in view of the huge volume of CO 2 exchanged in the lungs. However, unlike an a hydrosol, aluminosilicate dust in high concentrations, as in emergency use when water for appropriate preparation is not available, may temporarily desiccate the alveolar surface and hence may cause an extended need—expressed as coughing and temporary feeling of shortness of breath—for production of alveolar surfactant, as by type II cells. Even though only partial and temporary, such an administration process should be carefully monitored.
[0122] b. Except in utmost emergency, intravenous application should be avoided. Some specific concerns are obvious, such as deposition of adsorbent's particles in tissues. For an intravenous application, the particle size of the adsorbent in the injected solution should be <1 μm, preferably close to the particle size in the colloidal suspension. In order to prevent an eventual calcium deficiency shock, or iron deficiency in hemoglobin, and similar cation-dependent problems, the deionized adsorbents should be recharged with selected cations (e.g. calcium, iron, or magnesium cations).
[0123] c. In a hospital or similar setting, blood can be filtered (outside the body) through a bed of adsorbent. This method is important in a situation when the toxins in blood reach an otherwise uncontrollable concentration. The particle size should be between 200-500 μm to allow free flow of blood and an instant effect, and be pretreated as described above in b. to prevent any eventual cation adsorption problems.
[0124] Also, adsorbents may be selectively reionized by cation(s), which interfere with biochemical and biophysical processes in a pathogen (e.g., Ag + ) or, more specifically, interfere with production or maintenance of protective coats of pathogens (e.g., Cu ++ ).
[0000] 11. Prophylaxis
[0125] A. Dry and wet filters for gas masks, emergency homemade masks, mass transportation and building air filtration systems, etc.
[0126] B. Decontamination of skin and hair, clothing, homes and other enclosed or open areas
[0127] C. Decontamination of drinking water and food, especially fruit and vegetables.
[0000] 12. Other Bacteria Used:
[0128] Pseudomonas fluorescens, P. putida, Xanthomonas citri, B. brevi, Escherichia coli, Salmonella enteritidis, Citrobacter freundii, Enterobacter aerogenes, Enterococcus faecalis, Micrococcus luteus, Rhodospirillum rubrum , and Vibrio fisheri.
[0129] B. Viruses: All testing, experiments, observations, and evaluations of inhibition of viral enzymes were conducted in vivo, based on symptoms, under the generally accepted principle that viral metalloenzymes are practically the same in the molecular structure, and modus operandi of the metalloenzymes of higher life forms, especially bacteria.
[0130] Experiments upon Tobacco Mosaic Virus indicate that zeolites can be used as a universal viricide in agriculture (TMV affects almost 200 known genera of plants and causes serious damage in cultivated crops).
[0131] Primary leaves of twenty tomato seedlings were inoculated with TMV. Developed necrotic lesions were sprayed in parallel tests with a 10 g/liter water suspension (particles <75 μm) of virgin natural zeolites (chabazite and clinoptilolite), homoionized natural zeolites (chabazite and clinoptilolite), and synthetic Y, Beta, and ZMS-S zeolite powders. Spraying was repeated after 24 hours. With identical results in all tests, all lesions were dry within 2-3 days, and no new lesions developed in any of the treated plants. The tests also indicate a systemic effect of zeolites.
[0132] A suitable example is the apoenzyme of HIV protease, which is activated by zinc cations. It seems virtually impossible that a fundamental mutation would occur so as to enable the apoenzyme to be activated by some other source. If the ion changed, the same or other zeolites would be likely to adsorb it also.
[0133] In contrast, HIV protease inhibitors, such as saquinavir, ABT387, or ribavirin are known to be deactivated rapidly in the host by cytochrome P450 enzymes, so only a small fraction of the inhibitor encounters the virus. The host system has to “metabolize” most of the inhibitor drug, incurring severe side effects. To counter them, the protease inhibitor may be administered in combination with another drug, such as ritonavir, which suppresses cytochrome P450 enzymes, or steroids to prevent general immunologic overload It is highly desirable to identify inhibitors that operate directly upon viruses without likelihood of deactivation.
[0134] Notwithstanding that it is not known how the cytochrome enzymes identify the foreign chemicals, we can hypothesize with fair confidence that a zeolite, which does not react chemically and behaves—except for the adsorption—as an inert substance, will not be recognized by the cytochrome as xenobidtic and thus will not trigger any overload on the host's immune system. Too, the zeolite may be modified or synthesized in such a way that it cannot adsorb the specific metal cation of the cytochrome enzyme (an iron cation in P450), so no interference would likely occur.
[0135] Manifestations of herpes, such as so-called cold sores and fever blisters ( H. febrilis ), also yield to topical treatment. Phillipsite in the form of wetted powder ( — 75_m) eliminated such skin infection in a day or less. Furthermore, as an effective desiccant, zeolites quickly dry the sore area, speeding up the healing. Warts of viral origin (e.g., plantar warts) were eliminated likewise in a longer time—about 10-14 days—using wetted clinoptilolite powder incorporated in dressings, or adhesive bandages.
[0136] Severe symptoms of shingles (Herpes zoster) were eliminated within a week, healing within the next 14 days virtually without scarring. It is reasonable to assume ion adsorbents to have similar effects on other manifestations of viral infections, e.g., genital herpes, HPV, etc.
[0137] This rationale has been implemented successfully in upper respiratory infection symptomatically diagnosed as “common cold” generally considered being of viral origin. Liquid suspensions of zeolite particles in a range from 10 to 75 μm may be used as an inhalant to eliminate difficulty in breathing, and as a gargle to alleviate soreness of the throat. Concentrations of a few weight percent (e.g., 4%) are recommended for the aerosol, and somewhat higher (e.g., 10%) for the gargle.
[0138] C. In experiments with fungi (incl. yeasts), only the growth of Saccharomyces cerevisiae and Penicillium notatum was successfully inhibited by all tested species and forms of zeolites (inconclusive results were considered as negative). Virgin chabazite inhibited growth of Achlya spec., Saccharomyces cerevisiae, Penicillium notatum , and Candida kefyr (inconclusive results were considered as negative). Virgin phillipsite inhibited growth of Achlya spec., Saccharomyces cerevisiae , and Penicillium notatum . (inconclusive results were considered as negative).
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Methods of preparing and using natural or synthetic zeolitic compositions therapeutically, so as to alleviate, cure, or even preclude human host disease attributable to exposure to bacteria within the Bacillus anthracis group: comprising, B. anthracis, B. cereus, B. Mycoide , and B. thurigiensis . Human exposure to the first member of the group causes the usually fatal disease, anthrax, in the absence of such effective pretreatment.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of International Application No. PCT/EP2008/056135, filed on May 19, 2008, entitled “Hinge for Automotive Vehicle Doors,” which claims priority under 35 U.S.C. §119 to Application No. ES P200701559 filed on May 31, 2007, entitled “Hinge for Automotive Vehicle Doors,” the entire contents of which are hereby incorporated by reference.
FIELD OF THE INVENTION
The invention relates to a hinge for automotive vehicle doors of the type comprising two parts hingedly connected to one another, which is provided with a retention device for retaining infinite angular positions between the first and second parts.
BACKGROUND
Door hinges for vehicles incorporating retention devices are currently known, which retention devices allow the vehicle door to be stably released in one or several preset open positions, preventing the door form being prematurely and automatically closed in an unwanted manner.
By way of example, patent document EP1056916 describes a hinge incorporating a check mechanism for the purpose of providing controlled angular positions in which the hinge leaves forming the actual hinge are maintained such that the door can be released in the desired angular positions. To that end, a check body is provided having a plurality of check members which are pushed radially outwards to make contact with a surrounding check reaction member. The check body is preferably integral with a hinge leaf whereas the check reaction member is integral with the other hinge leaf, such that the rotation of the hinge leaves in relation to one another makes the check body rotate in relation to the check reaction member. The check members are ball-shaped, and the check reaction member has an inner annular face provided with a series of recesses in correspondence with the number of balls of the check body.
Patent document DE 19953077 describes a mechanical alternative for providing a hinge with multiple locking positions according to respective angular positions adopted by the hinge leaves in relation to one another. To that end, the check body is forced by elastic means to remain supported against the rotating surface of the pin of the hinge, which is integral with the mobile hinge leaf, the circumferential contour of which is suitably profiled or even beveled in order to achieve a continuous check effect between the hinge leaves when the pin of the hinge rotates about the hinge axis, and a locking in the angular positions in which the check body can be stably supported against the contour of the pin of the hinge.
Although the described embodiments allow the locking of the door in different angular positions, said locking positions are preset, therefore the door is not locked in any angular position chosen by a user. These designs lack a hinge incorporating a check device suitable for achieving a locking effect, or a retention effect, without the jerking of the door, such that from any one position of the door, the user, after overcoming an initial predetermined force for commencing the rotational movement of the door in either direction, can move the door to another position of interest and release it, the door being automatically retained again, maintaining the position in which it has been released.
Patent document DE 4406824 describes a door hinge for a motor vehicle with an integrated check and locking function which, in order to achieve a continuous check and a locking without the jerking of the vehicle door, proposes fixing the pin of the hinge in an anti-rotational manner in the support eye of a first hinge half and providing it with at least one radially upward wedge-shaped surface in its entire length in which it must be supported for its movement, and arranging opposite to this wedge surface at least one radially upward wedge surface in the inner perimeter of the borehole of the respective support eye of the second hinge half.
One of the drawbacks of this embodiment is that the opening movement of the door is continuously checked, this check furthermore increasing as the opening angle of the door increases.
SUMMARY
The hinge object of the invention is particularly, but not exclusively, suitable for automotive vehicle doors. The hinge in question is formed by two complementary parts joined to one another through an essentially vertical pin integral with the first of said parts, the latter being intended to be solidly fixed to a vehicle door, while the second part is intended to be solidly fixed to the frame of the vehicle.
The hinge is essentially characterized in that it is provided with a retaining device for retaining infinite angular positions between the first and second parts, comprising an essentially cylindrical and vertical first cavity, integral with the second part, in which all or part of the pin and an enveloping sleeve are housed, engagement means being arranged between the pin and the sleeve, which means keep them connected to one another in any angular rest position of the hinge and are suitable for automatically disconnecting them while a relative rotation between both parts of the hinge and therefore an opening or closing movement of the vehicle door occurs, and for also automatically connecting them when said relative rotation between both parts of the hinge is interrupted, direct actuation means of the engagement means being arranged at one of the ends of the enveloping sleeve.
According to another feature of the invention, the mentioned engagement means comprise at least one peripheral member contiguous to the pin which is longitudinally movable in relation to the latter between an engaged position and another disengaged position, through at least one corresponding groove made on the inner face of the enveloping sleeve, and subjected to the action of first elastic means tending to keep it in the engaged position, in which it is coupled with the pin by friction or through a mechanical coupling, and from which it is moved to the disengaged position by the action of the direct actuation means of the engagement means.
According to an embodiment variant, the mentioned direct actuation means of the engagement means are formed, for each peripheral member, by a respective cam portion arranged in a washer solidly joined to the second part, intended to be fixed to the frame of the vehicle.
According to another feature of the invention, the retaining device is provided with check means for the door and for the indirect actuation of the engagement means, which are introduced in a second cavity arranged transversely to the first cavity, which houses the pin and the enveloping sleeve, and connected to it, acting on the mentioned enveloping sleeve.
According to another feature of the invention, the check means for the door and for the indirect actuation of the engagement means are formed by a considerably horizontally arranged pushing rod introduced in the second cavity of the retaining device, which is subjected to the action of second elastic means pushing it against the enveloping sleeve and is provided with a planar pushing surface, while the outer face of the enveloping sleeve is provided with a planar bevel edge suitable for receiving the support of the pushing surface of the pushing rod during any relative rest position between both parts of the hinge, i.e. during any rest position of the door.
According to a particularly interesting variant of the invention, the rotation of the enveloping sleeve about its axis from the rest position to the position in which it is disconnected from the pin is equal to or less than half the angle separating the two radii passing through the ends of the bevel edge in a cross-section of the enveloping sleeve, whereby if the enveloping sleeve is rotated and no external force is exerted on it, it will return to its original position, the rest position of the hinge, aided by the pushing rod of the check means.
Advantageously, the retaining device is applicable to any hinged connection of two components pivotably connected through an axis of rotation, such as the two hinge leaves of a hinge assembly.
The device could thus be independent, directly integral with the second part of the hinge by welding or indirectly integral upon being fixed to a strut of the frame of the vehicle, or could be integrated in the parts forming a hinge assembly such that the essentially cylindrical first cavity housing the enveloping sleeve, the engagement means and the pin, and, where appropriate, the second cavity, inside which the check means are introduced, can be arranged in the second part of the hinge, forming an integrated part thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
The attached drawings show, by way of a non-limiting example, a hinge for vehicle doors according to the invention. Specifically:
FIG. 1 is an elevational and sectioned view of the hinge according to the invention;
FIG. 2 is a section according to II of the second part and of the enveloping sleeve of the hinge of FIG. 1 ;
FIGS. 3 a , 3 b and 3 c are respective schematic plan views of the hinge according to three different positions, the first of them being the rest position and the next two being the position of commencing a relative rotational movement between the first and second part forming the hinge, and the engaged position, respectively, in which the direct actuation means of the engagement means, the enveloping sleeve and the mentioned engagement means can be simultaneously observed;
FIGS. 4 a , 4 b and 4 c are respective schematic elevational views of a part of the hinge shown in FIGS. 3 a , 3 b and 3 c , respectively, sectioned according to a vertical plane; and
FIG. 5 is a perspective, partially sectioned view of the hinge of FIG. 1 .
DETAILED DESCRIPTION
FIGS. 1 and 4 show a retaining device for retaining infinite angular positions between two components pivotably connected through an axis of rotation.
In particular, in the example of FIGS. 1 and 4 , the two aforementioned components are formed by a first part 1 a and a second part 1 b of a hinge 1 of an automotive vehicle, the components of the retaining device being integrated in the body of the second part 1 b and the first part 1 a being integral with the axis of rotation about which both parts rotate, in this case the pin 7 of the hinge 1 .
The two complementary parts 1 a and 1 b are joined to one another in a known manner by means of the pin 7 of the hinge, essentially vertical in the operative position of the hinge 1 , which is integral with first part 1 a of the hinge 1 as has been stated above. In the mentioned operative position, the first part 1 a of the hinge is firmly fixed to a vehicle door whereas the second part 1 b of the hinge is firmly fixed to the chassis of the vehicle. The second part 1 b is provided with an essentially cylindrical and vertical first cavity 17 in which the pin 7 and an enveloping sleeve 5 are housed, engagement means 4 being arranged between the pin 7 and the enveloping sleeve 5 .
These engagement means 4 are formed by four peripheral members 4 a , 4 b , 4 c and 4 d arranged contiguous to the pin 7 and assembled in a movable manner through the inside of grooves 5 a , 5 b , 5 c and 5 d , respectively, made on the inner face of the enveloping sleeve 5 (see FIG. 2 ).
The peripheral members 4 a , 4 b , 4 c and 4 d and the grooves 5 a , 5 b , 5 c and 5 d are regularly distributed, spaced from one another, in the inner contour of the enveloping sleeve 5 , and the former are permanently subjected to the action of first elastic means 8 , shown in the form of a coil spring, pushing them against a washer 6 arranged at the upper end of the enveloping sleeve 5 , coaxial with the latter, integrally joined to the second part 1 b of the hinge 1 .
In the position shown in FIG. 3 a , corresponding to a rest or locking position, the upper ends 15 of the peripheral members 4 a , 4 b , 4 c and 4 d (see FIG. 1 ), configured as a wedge, are supported under pressure against a surface 16 , with a slope complementary to that of the peripheral members 4 a , 4 b , 4 c and 4 d , with which the pin 7 is provided, therefore the rotation of the pin 7 would cause the pulling, by friction, of the enveloping sleeve 5 , which would rotate simultaneously with the mentioned pin 7 . In other words, the pin 7 and the enveloping sleeve 5 are connected and the peripheral members 4 a , 4 b , 4 c and 4 d occupy an engaged position.
Alternatively, to cause the coupling between the pin 7 and the peripheral members 4 a , 4 b , 4 c and 4 d in the situation shown in FIG. 1 or in FIGS. 3 a and 4 a , the peripheral members 4 a , 4 b , 4 c and 4 d can be provided with at least one projection 14 intended to be fitted in a recess 13 provided for that purpose in the surface 16 of the pin 7 . As regards the washer 6 , it is provided with a series of cam portions 6 a , 6 b , 6 c and 6 d acting on the peripheral members 4 a , 4 b , 4 c and 4 d when a rotation of the pin 7 occurs.
Indeed, if a rotational movement of the vehicle door is commenced, it will be transmitted through the first part 1 a of the hinge 1 to pin 7 and due to the effect of the engagement means 4 to the enveloping sleeve 5 . When the enveloping sleeve 5 rotates, the peripheral members 4 a , 4 b , 4 c and 4 d will be moved downwards by the cam portions 6 a , 6 b , 6 c and 6 d of the washer 6 , which acts as actuation means of the engagement means 4 .
This situation has been shown in FIG. 3 b , in which it is observed that the enveloping sleeve 5 has rotated an angle A 1 in relation to the situation it occupied in FIG. 3 a . FIG. 4 b shows how the profile of the cam portion 6 a makes contact with the upper end 4 a ′ of the peripheral member 4 a , which would cause its movement towards a disengaged position, shown in FIGS. 3 c and 4 c , if the rotation of the pin 7 continues.
In FIGS. 3 c and 4 c , the enveloping sleeve 5 has rotated a greater angle A 2 in relation to the situation it occupied in FIG. 3 a as a result of continuing the rotation of the vehicle door, and it is observed that the peripheral member 4 a has been moved in the direction indicated by the arrow of FIG. 4 c , the first elastic means 8 , not shown in this FIG. 4 c , being compressed.
When this occurs, the automatic disengagement and the disconnection between the pin 7 and the enveloping sleeve 5 occurs when the connection between the projection 14 of the peripheral members 4 a , 4 b , 4 c and 4 d and the recess 13 of the mentioned pin 7 is disabled or the contact surfaces 15 and 16 of said peripheral members 4 a , 4 b , 4 c and 4 d and the pin 7 are separated, respectively. As a result, the pin 7 can rotate freely without pulling the enveloping sleeve 5 and therefore the vehicle door can rotate without a significant check.
For the purpose of increasing the retention of the vehicle door in the desired rest position, the hinge further comprises check means 18 introduced in a second cavity 19 arranged transversely to the first cavity 17 and connected to it, acting on the enveloping sleeve 5 , all of this as shown in FIGS. 1 , 3 a , 3 b , 3 c and 4 .
These check means 18 are formed by a considerably horizontally arranged pushing rod 2 introduced in the second cavity 19 of the second part 1 b , and which is subjected to the action of second elastic means 3 pushing it against the enveloping sleeve 5 such that to commence a rotational movement of the door it is necessary to overcome the force exerted by the pushing rod 2 on the enveloping sleeve 5 .
Advantageously, the pushing rod is provided with a planar pushing surface 20 and the outer face of the enveloping sleeve 5 is provided with an also planar bevel edge 10 suitable for receiving the support of the pushing surface of the pushing rod 2 during any relative rest position between both parts of the hinge, i.e. during any rest position of the door.
As observed in FIG. 3 c , the bevel edge 10 is configured such that the rotation angle A 2 of the enveloping sleeve 5 about its axis 12 from the rest position to the position in which it is disconnected from the pin 7 is equal to or less than half the angle A 3 separating the two radii r 1 and r 2 passing through the ends of the bevel edge 10 (see FIG. 2 ), such that if no force is exerted on the enveloping sleeve 5 from the outside, for example when the door is released and its rotational movement is stopped, the pushing force imparted by the second elastic means 3 to the pushing rod 2 causes the latter to again place the enveloping sleeve 5 in its initial position, rotating it until reaching the stable or rest position shown in FIG. 3 a , in which the planar pushing surface 20 of the pushing rod is supported against the planar bevel edge 10 of the enveloping sleeve 5 .
The rotation of the enveloping sleeve 5 in turn causes the engagement means 4 to be automatically arranged in the engaged position shown in FIGS. 1 and 3 a due to the effect of the first elastic means 8 . For this reason, it can be considered that the check means 18 are also indirect actuation means of the engagement means 4 .
Although the retaining device has been shown integrated in one of the parts of the hinge, it is also provided that the retaining device is assembled separately, such that the enveloping sleeve 5 is tightly housed inside a cavity of the outer casing of the device, which in turn would be useful as a support of the check means 18 . In this case, for its application to any one hinge, it is only necessary to fix said casing to a first hinge component, for example to the second part 1 b of a hinge similar to that of FIG. 1 , or to a fixed part of the vehicle, and to firmly join the second hinge component, for example the first part 1 a of a hinge similar to that shown in FIG. 1 , to one of the free ends of the pin 7 partially housed inside the enveloping sleeve 5 .
It is furthermore stated that the hinge 1 provided with the retaining device according to the invention, integrated or not in one of the parts of the hinge, is detachable, the two parts of the hinge being able to be separated without having to disassemble or uncouple the components of the retaining device.
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A hinge for vehicle doors includes: a first part fixable to a vehicle door and including an essentially vertical pin; a second part fixable to a frame of the vehicle and including an essentially cylindrical and vertical first cavity that houses the vertical pin; and a retaining device that retains infinite angular positions between the first and second parts. The retaining device includes: a sleeve surrounding the pin in the first cavity and an engagement member arranged between the pin and the sleeve. The engagement member couples the sleeve to the pin in any angular rest position of the hinge and automatically decouples the sleeve from the pin during relative rotation between the first and second parts. An interruption of the relative rotation between the first and second parts causes the engagement member to automatically couple the sleeve to the pin.
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BACKGROUND OF THE INVENTION
Various intensity earthquakes often take place at various areas in the world; unfortunately, the earthquake cannot with present technology be anticipated as we often can do in the case of a typhoon. As a result, human beings can do nothing about earthquakes. There is one thing we can do, i.e., a person in a house can take cover under an item of furniture in case of an earthquake; such a way of taking cover has been announced often through television or other media. Unfortunately, it is difficult to be able to take cover under conventional furniture; according to our experience, only small (non adult) children can take cover under a piece of furniture,; further, almost none of the furnitures is designed particularly for earthquake considerations; therefore, conventional furniture might not be good enough for a small child to take cover therein. It is a problem that the furniture dealer has difficulty to manufacture antiquake furniture. Strong funiture must be made of metal; most of the conventional furnitures are assembled together by means of welding or casting to provide the desired strength; however, such a strong furniture usually is incapable of being moved into a room as a result of its large dimensions. High strength furniture may be disassembled while being being moved into a room; in which case, the furniture may be assembled in the room by welding methods, but it is questionable that such a procedure would be accepted by the owner or buyer. Of course, funiture may be assembled together with screws, or rivets or other conventional methods, but the strength thereof will be reduced considerably.
SUMMARY OF THE INVENTION
This invention relates to an anti-quake-furniture, and particularly to a furniture, such as a bed or cabinet, to be assembled together by means of a series of insertion and sleeve members being arranged longitudinally or laterally. The present invention comprises a top lid, a plurality of Mid pole structures, a base frame and a plurality of fastening members. The four edges of the top lid are provided with a plurality of vertical poles with pointed connecting ends and connecting sleeves and depending from the top lid; the four edges of the base frame also have a plurality of connecting ends with connecting sleeves and slot holes respectively; the connecting sleeves are to be mated with the lower connecting ends and sleeves respectively; the furniture is substantially a cubic structure. All the mid-pole structures are assembled together by means of one or two fastening members so as to have the top lid, the mid-pole structures, and the base frame assembled together firmly as one piece.
The prime feature of the present invention is to provide an anti-quake furniture to be set in house as a normal furniture (such as a bed or cabinet), and the furniture can also be used as a haven in case of earthquake.
Another feature of the present invention is to provide an anti-quake furniture, which is assembled together by means of a series of longitudinal and lateral insertion and sleeve members; all the main elements of the furniture can be moved freely through a door of 50 C.M. width. Furniture of the present invention is to be assembled easily without welding or using other conventional methods.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an embodiment according to the present invention.
FIG. 2 is a disassembled view of the present invention.
FIG. 3 is another perspective view of the present invention.
FIG. 4 is a sectional view of a connecting end being assembled together with a corresponding connecting sleeve according to the present invention.
FIG. 5 is a perspective view of a connecting end being assembled together with a corresponding connecting sleeve according to the present invention.
DETAILED DESCRIPTION
Referring to FIGS. 1 and 2, the present invention comprises a top lid 1, three types of fence structures 2,3, and 4, a base frame 5, and three fastening members 6,7 and 8. The top lid 1 is a rectangular member with a plurality of vertical poles 12 on four edges thereof, each vertical pole having a pointed connecting end 121. The inner side of each connecting end 121 has a tubular connector 13 with a slot hole 131. All the vertical poles 12 are arranged regularly so as to depend from the four sides of the top lid 1, except that a part of edge 11 does not have vertical poles (as shown in FIG. 3). The outer sides of selected vertical poles 12 on another edge 14 of lid 1 have tubular connectors 15. The fence structure 2 is comprised of vertical poles 21 arranged in a L-shaped fence configuration. Both ends of the vertical poles 21 are formed into pointed connecting ends 211 and 212 respectively. The outer side of the upper connecting end 211 of each pole 21 has a connecting sleeve 22 with a slot hole 221; the outer side of the lower connecting end has a connecting sleeve 23 with a slot hole 231. The zone of a terminal vertical pole 24 is connected with two connecting sleeves 27 and 28 which are on the connecting points of two lateral rods 25 and 26 respectively. The two connecting sleeves 27 and 28 have two slot holes 271 and 281 repectively. The poles in fence structure 3 are arranged regularly in a J-shaped fence configuration, in which each of the vertical poles 31 has two pointed connecting ends 311 and 312; the outer side of the upper connecting end 311 has a connecting sleeve 32 with a slot hole 321, while the outer side of the lower connecting end 312 has a connecting sleeve 33 with a slot hole 331. The outer side of a terminal vertical pole 34 is connected with two connecting sleeves 37 and 38 on the connecting points with the lateral rods 35 and 36 respectively. Both connecting sleeves 37 and 38 have slot holes 371 and 381 respectively. The poles in fence structure 4 are arranged in a straight-line-shaped fence configuration, of which each vertical pole 41 has two pointed connecting ends 411 and 412; the outer side of the upper connecting end 411 has a connecting sleeve 42 with slot hole 421, whole the outer side of the lower ennecting end 412 has a connecting sleeve 43 with a slat hole 431. The connecting points with the lateral rods 44 and 45 are mounted with connecting sleeves 46 and 47 respectively. The base frame 5 is a rectangular member, of which the four sides and the bottom are all flat members; the upper part of the base frame is a grid-shaped supporting rack 51. The four sides of the base frame 5 are furnished with a plurality of tubular connectors 52 with slot holes 521; each of the tubular connectors 52 has a pointed connecting end or prong 53 on the outer side thereof. One side 54 of the base frame that is corresponding to the edge 11 of the top lid 11 has a portion without tubular connectors 52 and connecting ends 53. The fastening members 6, 7 and 8 look like rakes. The lateral rod 61 has a plurality of connecting ends 62 arranged perpendicularly to the rod 61.
As shown in FIGS. 2 and 3, the furniture item of the present invention can be assembled together by having the lower connecting ends 212 and the tubular sleeves 23 connected with the connecting connectors 52 and the connecting ends 53 on the short side 55 and the long side 56 of the base frame 5 so as to have the fence structure 2 fixed on the base frame 5; the connecting method is shown in FIGS. 4 and 5. Each connecting sleeve 32 and the connecting end 311 are joined into one piece by having the connecting end 311 inserted into the associated tubular connector 13, while the tubular connector 13 and the connecting end 121 are joined into one piece by having the connecting end 121 inserted into the connecting sleeve 32. In the case of fence structure 3, the lower connecting ends 312 with connectin sleeves 33 are joined together with the corresponding tubular connectors 52 and connecting ends 53 on the long sides 54 and 56, the short side 57 of the base frame so as to fix the fence structure 3 on the base frame 5. In the case of fence structure 4, the lower connecting ends 412 with connecting sleeves 43 of the vertical poles 41 are joined together with the corresponding tubular connectors 52 and the connecting ends 53 on the long side 56 of the base frame 5 so as to fix the fence structure on the base frame 5; likewise, the connecting ends 121 with tubular connectors 13 of the vertical poles 12 of the top lid 1 are joined together with the upper connecting sleeves 22,32, and 42, and the connecting ends 211. 311 and 411 of the fence structures 2, 3 and 4 respectively so as to fix the top lid 1, the fence structures 2, 3 and 4, and the base frame together into a cubic structure. The connecting ends 62 of the fastening members 6 are to be joined together with the connecting sleeves 27, 46 and 37 on the vertical poles 24, 41 and 34 of the fence structures 2, 3 and 4 respectively. The fastening member 7 is to be joined with the connecting sleeves 28, 47 and 38, and the fastening member 8 is also mounted in the tubular connectors 15 of the top lid 1, so as to join the three fence structures with the top lid 1. Fence structures 2,3 and 4 are connected to the base frame 5 by means of the fastening member 7; the fence structures 2, 3 and 4 are thus formed into a fence system around the four sides of the base frame 5 except the edge 11 having an opening (as shown in FIG. 3) to be used as an entrance for person. The present invention is substantially a strong furniture structure; the beautiful decoration of the furniture may be varied in accordance with individual's favor. Since the present invention is assembled by means of connecting ends and sleeves without using any welding process and other conventional methods, its strong structure is still much stronger than the welding process. In fact, the welding process is merely a point or a plane connection, but the sleeve-connecting method as used in the present invention is a large and cubic space connection; therefore, a furniture according to the present invention is deemed the best haven in case of earthquake.
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An anti-quake furniture comprising a top lid, a plurality of mid-pole structures a base frame and a plurality of fastening members; the top lid, the mid-poles and the base frame are assembled together by means of a plurality of connecting ends and connecting sleeves self-contained on the aforesaid major members to form a cubic structure. The various mid-pole structures are assembled together with the fastening members so as to have the top lid, the mid-pole structures, and the base frame assembled into a strong furniture to be used as a haven in case of earthquake.
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CROSS-REFERENCES TO RELATED APPLICATIONS
This application is a continuation-in-part of application of U.S. Ser. No. 11/765,516, filed on Jun. 20, 2007 now U.S. Pat. No. 7,396,808 which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to cleaning compositions and methods for use on hard surfaces. The invention also relates to cleaning compositions for use with cleaning substrates, cleaning heads, cleaning pads, cleaning sponges and related systems for cleaning hard surfaces. The composition also relates to natural cleaning compositions having a limited number of ingredients and having good cleaning properties and low residue.
2. Description of the Related Art
Cleaning formulations have progressed and created a large chemical industry devoted to developing new synthetic surfactants and solvents to achieve ever improving cleaning compositions for the consumer. Because of a desire to use renewable resources, natural based cleaners are gaining increasing interest. Most of these cleaners contain only some natural ingredients. One difficulty in formulating natural based cleaners is achieving acceptable consumer performance with a limited number of natural components compared to highly developed formulations using synthetic surfactants and solvents.
Typical cleaning formulations require multiple surfactants, solvents, and builder combinations to achieve adequate consumer performance. For example, U.S. Pat. No. 5,025,069 to Deguchi et al. discloses alkyl glycoside detergent systems with anionic, amphoteric and nonionic surfactant ingredients. U.S. Pat. No. 7,182,950 to Garti et al. discloses nano-sized concentrates with examples using Tween® surfactants. U.S. Pat. No. 6,831,050 to Murch et al. discloses toxicologically acceptable cleaners containing oleic acid and citric acid. U.S. Pat. No. 6,302,969 to Moster et al. discloses natural cleaners containing anionic surfactants. U.S. Pat. No. 6,420,326 to Maile et al. discloses glass cleaners with ethanol, glycol ethers, and anionic surfactants.
Prior art compositions do not combine effective cleaning with a minimum number of ingredients, especially with natural ingredients. It is therefore an object of the present invention to provide a cleaning composition that overcomes the disadvantages and shortcomings associated with prior art cleaning compositions.
SUMMARY OF THE INVENTION
In accordance with the above objects and those that will be mentioned and will become apparent below, one aspect of the present invention comprises a hard surface cleaning composition consisting essentially of 0.5 to 5% alkyl polyglucoside; 0.5 to 5% ethanol; 0.05 to 0.4% lemon oil or d-limonene; less than 0.2% builder; water; and optionally dyes, colorants, and preservatives.
In accordance with the above objects and those that will be mentioned and will become apparent below, another aspect of the present invention comprises a hard surface cleaning composition consisting essentially of 0.5 to 5% alkyl polyglucoside; 0.5 to 5% ethanol; 0.05 to 1% glycerol; 0.01 to 0.4% essential oil; less than 0.2% builder; water; and optionally dyes, colorants, and preservatives.
In accordance with the above objects and those that will be mentioned and will become apparent below, another aspect of the present invention comprises a method for cleaning a hard surface with a natural composition wherein said composition comprises at least 95% natural ingredients, said method comprising: contacting said surface with said composition, wherein said composition consists essentially of: 0.5 to 5% alkyl polyglucoside; 0.5 to 5% ethanol; less than 0.2% builder; water; and optionally dyes, colorants, and preservatives.
Further features and advantages of the present invention will become apparent to those of ordinary skill in the art in view of the detailed description of preferred embodiments below, when considered together with the attached claims.
DETAILED DESCRIPTION OF THE INVENTION
Before describing the present invention in detail, it is to be understood that this invention is not limited to particularly exemplified systems or process parameters that may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments of the invention only, and is not intended to limit the scope of the invention in any manner.
All publications, patents and patent applications cited herein, whether supra or infra, are hereby incorporated by reference in their entirety to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated by reference.
It must be noted that, as used in this specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless the content clearly dictates otherwise. Thus, for example, reference to a “surfactant” includes two or more such surfactants.
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 invention pertains. Although a number of methods and materials similar or equivalent to those described herein can be used in the practice of the present invention, the preferred materials and methods are described herein.
In the application, effective amounts are generally those amounts listed as the ranges or levels of ingredients in the descriptions, which follow hereto. Unless otherwise stated, amounts listed in percentage (“%'s”) are in weight percent (based on 100% active) of the cleaning composition alone, not accounting for the substrate weight. Each of the noted cleaner composition components and substrates is discussed in detail below.
The term “cleaning composition”, as used herein, is meant to mean and include a cleaning formulation having at least one surfactant.
The term “surfactant”, as used herein, is meant to mean and include a substance or compound that reduces surface tension when dissolved in water or water solutions, or that reduces interfacial tension between two liquids, or between a liquid and a solid. The term “surfactant” thus includes anionic, nonionic and/or amphoteric agents.
Alkyl Polyglucoside
The cleaning compositions contain alkyl polyglucoside surfactant. The cleaning compositions preferably have an absence of other nonionic surfactants, expecially synthetic nonionic surfactants, such as ethoxylates. The cleaning compositions preferably have an absence of other surfactants, such as anionic, cationic, and amphoteric surfactants. Suitable alkyl polyglucoside surfactants are the alkylpolysaccharides that are disclosed in U.S. Pat. No. 5,776,872 to Giret et al.; U.S. Pat. No. 5,883,059 to Furman et al; U.S. Pat. No. 5,883,062 to Addison et al.; and U.S. Pat. No. 5,906,973 to Ouzounis et al., which are all incorporated by reference. Suitable alkyl polyglucosides for use herein are also disclosed in U.S. Pat. No. 4,565,647 to Llenado describing alkylpolyglucosides having a hydrophobic group containing from about 6 to about 30 carbon atoms, or from about 10 to about 16 carbon atoms and polysaccharide, e.g., a polyglycoside, hydrophilic group containing from about 1.3 to about 10, or from about 1.3 to about 3, or from about 1.3 to about 2.7 saccharide units. Optionally, there can be a polyalkyleneoxide chain joining the hydrophobic moiety and the polysaccharide moiety. A suitable alkyleneoxide is ethylene oxide. Typical hydrophobic groups include alkyl groups, either saturated or unsaturated, branched or unbranched containing from about 8 to about 18, or from about 10 to about 16, carbon atoms. Suitably, the alkyl group can contain up to about 3 hydroxy groups and/or the polyalkyleneoxide chain can contain up to about 10, or less than about 5, alkyleneoxide moieties. Suitable alkyl polysaccharides are octyl, nonyldecyl, undecyldodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl, di-, tri-, tetra-, penta-, and hexaglucosides, galactosides, lactosides, glucoses, fructosides, fructoses and/or galactoses. Suitable mixtures include coconut alkyl, di-, tri-, tetra-, and pentaglucosides and tallow alkyl tetra-, penta-, and hexaglucosides.
Suitable alkylpolyglycosides (or alkylpolyglucosides) have the formula: R 2 O(C n H 2n O) t (glucosyl) x wherein R 2 is selected from the group consisting of alkyl, alkylphenyl, hydroxyalkyl, hydroxyalkylphenyl, and mixtures thereof in which the alkyl groups contain from about 10 to about 18, preferably from about 12 to about 14, carbon atoms; n is about 2 or about 3, preferably about 2; t is from 0 to about 10, preferably 0; and x is from about 1.3 to about 10, preferably from about 1.3 to about 3, most preferably from about 1.3 to about 2.7. The glycosyl is preferably derived from glucose. To prepare these compounds, the alcohol or alkylpolyethoxy alcohol is formed first and then reacted with glucose, or a source of glucose, to form the glucoside (attachment at the 1-position). The additional glycosyl units can then be attached between their 1-position and the preceding glycosyl units 2-, 3-, 4-and/or 6-position, preferably predominantely the 2-position.
A group of alkyl glycoside surfactants suitable for use in the practice of this invention may be represented by Formula I below:
RO—(R 2 O) y -(G) x Z b Formula I
wherein R is a monovalent organic radical containing from about 6 to about 30 (preferably from about 8 to about 18) carbon atoms; R 2 is a divalent hydrocarbon radical containing from about 2 to about 4 carbon atoms; 0 is an oxygen atom; y is a number which has an average value from about 0 to about 1 and is preferably 0; G is a moiety derived from a reducing saccharide containing 5 or 6 carbon atoms; and x is a number having an average value from about 1 to 5 (preferably from 1.1 to 2); Z is O 2 M 1 , O 2 CR 3 , O(CH 2 ), CO 2 M 1 , OSO 3 M 1 , or O(CH 2 )SO 3 M 1 ;R 3 is CH 2 )CO 2 M 1 or CH═CHCO 2 M 1 ; (with the proviso that Z can be O 2 M 1 only if Z is in place of a primary hydroxyl group in which the primary hydroxyl-bearing carbon atom, —CH 2 OH, is oxidized to form a —CO 2 M 1 group); b is a number from 0 to 3x+1 preferably an average of from 0.5 to 2 per glycosal group; p is 1 to 10, M 1 is H + or an organic or inorganic cation, such as, for example, an alkali metal, ammonium, monoethanolamine, or calcium. As defined in Formula I, R is generally the residue of a fatty alcohol having from about 8 to 30 or 8 to 18 carbon atoms. Suitable alkylglycosides include, for example, APG 325® (g (a C 9 -C 11 alkyl polyglycoside available from Cognis Corporation), APG 625® (a C 10 -C 16 alkyl polyglycoside available from Cognis Corporation), Dow Triton® CG110 (a C 8 -C 10 alkyl polyglycoside available from Dow Chemical Company), AG6202® (a C 8 alkyl polyglycoside available from Akzo Nobel) and Alkadet 15® (a C 8 -C 10 alkyl polyglycoside available from Huntsman Corporation). A C6 to C10 alkylpolyglucoside includes alkylpolyglucosides wherein the alkyl group is substantially C6 alkyl, substantially C8 alkyl, substantially C10 alkyl, or a mixture of substantially C6, C8 and C 10 alkyl. A C8 to C 10 alkylpolyglucoside includes alkylpolyglucosides wherein the alkyl group is substantially C8 alkyl, substantially C10 alkyl, or a mixture of substantially C8 and C10 alkyl. Suitably, the alkyl polyglycoside is present in the cleaning composition in an amount ranging from about 0.01 to about 5 weight percent, or 0.1 to 5.0 weight percent, or 0.5 to 5 weight percent, or 0.5 to 4 weight percent, or 0.5 to 3 weight percent, or 0.5 to 2 weight percent, or 0.1 to 0.5 weight percent, or 0.1 to 1.0 weight percent, or 0.1 to 2.0 weight percent, or 0.1 to 3.0 weight percent, or 0.1 to 4.0 weight percent.
Ethanol
The cleaning compositions contain the organic solvent ethanol, either absolute, various dilutions with water or denatured alcohol, for example denatured with isopropanol. Natural forms of ethanol can be derived from the fermentation of biomass or the hydrolysis of cellulose. Synthetic ethanol can be derived from the catalytic hydration of ethylene. The compositions suitably do not contain additional solvents, especially synthetic solvents such as glycol ethers. Suitably, the ethanol is present in the cleaning composition in an amount ranging from about 0.01 to about 5 weight percent, or 0.1 to 5.0 weight percent, or 0.1 to 4.0 weight percent, or 0.1 to 3.0 weight percent, or 0.1 to 2.0 weight percent, or 0.1 to 1.0 weight percent, or 0.5 to 5.0 weight percent, or 0.5 to 4.0 weight percent, or 0.5 to 3.0 weight percent, or 0.5 to 2.0 weight percent, or 0.5 to 1.0 weight percent.
Glycerol
The cleaning compositions can optionally contain glycerol, or glycerin. The glycerol may be natural, for example from the saponification of fats in soap manufacture, or synthetic, for example by the oxidation and hydrolysis of allyl alcohol. The glycerol may be crude or highly purified. The glycerol can serve to compatibilize the alkyl polyglucoside, the ethanol and the lemon oil or d-limonene. Proper compatibilization of these components in suitable ratios, such as demonstrated in the examples below, allow these limited components to perform as well as complex formulated conventional synthetic cleaning compositions. Suitably, the glycerol is present in the cleaning composition in an amount ranging from about 0.01 to about 2 weight percent, or 0.05 to 2.0 weight percent, or 0.05 to 1.0 weight percent, or 0.05 to 0.5 weight percent, or 0.05 to 1.0 weight percent, or 0.10to 2.0 weight percent, or 0.10 to 1.0 weight percent, or 0.10 to 0.5 weight percent.
Lemon Oil d-limonene and Other Essential Oils
The cleaning compositions can optionally contain natural essential oils or fragrances containing d-limonene or lemon oil or d-limonene. Lemon oil or d-limonene helps the performance characteristics of the cleaning composition to allow suitable consumer performance with natural ingredients and a minimum of ingredients. Lemon oil and d-limonene compositions which are useful in the invention include mixtures of terpene hydrocarbons obtained from the essence of oranges, e.g., cold-pressed orange terpenes and orange terpene oil phase ex fruit juice, and the mixture of terpene hydrocarbons expressed from lemons and grapefruit. The essential oils may contain minor, non-essential amounts of hydrocarbon carriers. Suitably, lemon oil, d-limonene, or essential oils containing d-limonene are present in the cleaning composition in an amount ranging from about 0.01 to about 0.50 weight percent, or 0.01 to 0.40 weight percent, or 0.01 to 0.30 weight percent, or 0.01 to 0.25 weight percent, or 0.01 to 0.20 weight percent, or 0.01 to 0.10 weight percent, or 0.05 to 0.40 weight percent, or 0.05 to 0.30 weight percent, or 0.05 to 0.25 weight percent, or 0.05 to 0.20 weight percent, or 0.05 to 0.10 weight percent.
Essential oils include, but are not limited to, those obtained from thyme, lemongrass, citrus, lemons, oranges, anise, clove, aniseed, pine, cinnamon, geranium, roses, mint, lavender, citronella, eucalyptus, peppermint, camphor, sandalwood, rosmarin, vervain, fleagrass, lemongrass, ratanhiae, cedar and mixtures thereof. Preferred essential oils to be used herein are thyme oil, clove oil, cinnamon oil, geranium oil, eucalyptus oil, peppermint oil, mint oil or mixtures thereof.
Actives of essential oils to be used herein include, but are not limited to, thymol (present for example in thyme), eugenol (present for example in cinnamon and clove), menthol (present for example in mint), geraniol (present for example in geranium and rose), verbenone (present for example in vervain), eucalyptol and pinocarvone (present in eucalyptus), cedrol (present for example in cedar), anethol (present for example in anise), carvacrol, hinokitiol, berberine, ferulic acid, cinnamic acid, methyl salycilic acid, methyl salycilate, terpineol and mixtures thereof. Preferred actives of essential oils to be used herein are thymol, eugenol, verbenone, eucalyptol, terpineol, cinnamic acid, methyl salycilic acid, and/or geraniol.
Other essential oils include Anethole 20/21 natural, Aniseed oil china star, Aniseed oil globe brand, Balsam (Peru), Basil oil (India), Black pepper oil, Black pepper oleoresin 40/20, Bois de Rose (Brazil) FOB, Borneol Flakes (China), Camphor oil, Camphor powder synthetic technical, Canaga oil (Java), Cardamom oil, Cassia oil (China), Cedarwood oil (China) BP, Cinnamon bark oil, Cinnamon leaf oil, Citronella oil, Clove bud oil, Clove leaf, Coriander (Russia), Coumarin (China), Cyclamen Aldehyde, Diphenyl oxide, Ethyl vanilin, Eucalyptol, Eucalyptus oil, Eucalyptus citriodora, Fennel oil, Geranium oil, Ginger oil, Ginger oleoresin (India), White grapefruit oil, Guaiacwood oil, Gurjun balsam, Heliotropin, Isobomyl acetate, Isolongifolene, Juniper berry oil, L-methyl acetate, Lavender oil, Lemon oil, Lemongrass oil, Lime oil distilled, Litsea Cubeba oil, Longifolene, Menthol crystals, Methyl cedryl ketone, Methyl chavicol, Methyl salicylate, Musk ambrette, Musk ketone, Musk xylol, Nutmeg oil, Orange oil, Patchouli oil, Peppermint oil, Phenyl ethyl alcohol, Pimento berry oil, Pimento leaf oil, Rosalin, Sandalwood oil, Sandenol, Sage oil, Clary sage, Sassafras oil, Spearmint oil, Spike lavender, Tagetes, Tea tree oil, Vanilin, Vetyver oil (Java), and Wintergreen. Each of these botanical oils is commercially available.
Builders
The cleaning compositions contain less than 0.2% builder, or no builder. Suitably, the builder is present in the cleaning composition in an amount ranging from about 0.01 to about 0.2 weight percent, or 0.01 to less than 0.2 weight percent, or 0.01 to 0.15 weight percent, or 0.01 to 0.10 weight percent, or 0.01 to 0.05 weight percent. The builder can be selected from inorganic builders, such as alkali metal carbonate, alkali metal bicarbonate, alkali metal hydroxide, alkali metal silicate and combinations thereof. These builders are often obtained from natural sources.
The cleaning composition can include a builder, which increases the effectiveness of the surfactant. The builder can also function as a softener, a sequestering agent, a buffering agent, or a pH adjusting agent in the cleaning composition. A variety of builders or buffers can be used and they include, but are not limited to, phosphate-silicate compounds, zeolites, alkali metal, ammonium and substituted ammonium polyacetates, trialkali salts of nitrilotriacetic acid, carboxylates, polycarboxylates, carbonates, bicarbonates, polyphosphates, aminopolycarboxylates, polyhydroxy-sulfonates, and starch derivatives. Builders, when used, include, but are not limited to, organic acids, mineral acids, alkali metal and alkaline earth salts of silicate, metasilicate, polysilicate, borate, hydroxide, carbonate, carbamate, phosphate, polyphosphate, pyrophosphates, triphosphates, tetraphosphates, ammonia, hydroxide, monoethanolamine, monopropanolamine, diethanolamine, dipropanolamine, triethanolamine, and 2-amino-2methylpropanol. Preferred buffering agents for compositions of this invention are nitrogen-containing materials. Some examples are amino acids such as lysine or lower alcohol amines like mono-, di-, and tri-ethanolamine. Other preferred nitrogen-containing buffering agents are tri(hydroxymethyl) amino methane (TRIS), 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-propanol, 2-amino-2-methyl-1,3-propanol, disodium glutamate, N-methyl diethanolarnide, 2-dimethylamino-2-methylpropanol (DMAMP), 1,3-bis(methylamine)-cyclohexane, 1,3-diamino-propanol N,N′-tetra-methyl-1,3-diamino-2-propanol, N,N-bis(2-hydroxyethyl)glycine (bicine) and N-tris(hydroxymethyl)methyl glycine (tricine). Other suitable buffers include ammonium carbamate, citric acid, and acetic acid. Mixtures of any of the above are also acceptable. Useful inorganic buffers/alkalinity sources include ammonia, the alkali metal carbonates and alkali metal phosphates, e.g., sodium carbonate, sodium polyphosphate. For additional buffers see WO 95/07971, which is incorporated herein by reference. Other preferred pH adjusting agents include sodium or potassium hydroxide. The term silicate is meant to encompass silicate, metasilicate, polysilicate, aluminosilicate and similar compounds.
pH
The pH of the cleaning composition is measured directly without dilution. The cleaning compositions can have a pH or 7 or above, or 7.5 or above, or 8 or above, or 9 or above, or 10 or above, or from 7.5 to 11, or from 8 to 11, or from 9 to 11.
Dyes, Colorants and Preservatives
The cleaning compositions optionally contain dyes, colorants and preservatives, or contain one or more, or none of these components. These dyes, colorants and preservatives can be natural (occurring in nature or slightly processed from natural materials) or synthetic. Natural preservatives include benzyl alcohol, potassium sorbate and bisabalol; sodium benzoate and 2-phenoxyethanol. Preservatives, when used, include, but are not limited to, mildewstat or bacteriostat, methyl, ethyl and propyl parabens, short chain organic acids (e.g. acetic, lactic and/or glycolic acids), bisguanidine compounds (e.g. Dantagard and/or Glydant) and/or short chain alcohols (e.g. ethanol and/or IPA). The mildewstat or bacteriostat includes, but is not limited to, mildewstats (including non-isothiazolone compounds) including Kathon GC, a 5-chloro-2-methyl-4-isothiazolin-3-one, KATHON ICP, a 2-methyl-4-isothiazolin-3-one, and a blend thereof, and KATHON 886, a 5-chloro-2-methyl-4-isothiazolin-3-one, all available from Rohm and Haas Company; BRONOPOL, a 2-bromo-2-nitropropane 1, 3 diol, from Boots Company Ltd., PROXEL CRL, a propyl-p-hydroxybenzoate, from ICI PLC; NIPASOL M, an o-phenyl-phenol, Na + salt, from Nipa Laboratories Ltd., DOWICIDE A, a 1,2-Benzoisothiazolin-3-one, from Dow Chemical Co., and IRGASAN DP 200, a 2,4,4′-trichloro-2-hydroxydiphenylether, from Ciba-Geigy A. G. Dyes and colorants include synthetic dyes such as Liquitint® Yellow or Blue or natural plant dyes or pigments, such as a natural yellow, orange, red, and/or brown pigment, such as carotenoids, including, for example, beta-carotene and lycopene.
Substances Generally Recognized As Safe
Compositions according to the invention may comprise substances generally recognized as safe (GRAS), including essential oils, oleoresins (solvent-free) and natural extractives (including distillates), and synthetic flavoring materials and adjuvants. Compositions may also comprise GRAS materials commonly found in cotton, cotton textiles, paper and paperboard stock dry food packaging materials (referred herein as substrates) that have been found to migrate to dry food and, by inference may migrate into the inventive compositions when these packaging materials are used as substrates for the inventive compositions.
Suitable GRAS materials are listed in the Code of Federal Regulations (CFR) Title 21 of the United States Food and Drug Administration, Department of Health and Human Services, Parts 180.20, 180.40 and 180.50, which are hereby incorporated by reference. These suitable GRAS materials include essential oils, oleoresins (solvent-free), and natural extractives (including distillates). The GRAS materials may be present in the compositions in amounts of up to about 10% by weight, preferably in amounts of 0.01 and 5% by weight.
Prefered GRAS materials include oils and oleoresins (solvent-free) and natural extractives (including distillates) derived from alfalfa, allspice, almond bitter (free from prussic acid), ambergris, ambrette seed, angelica, angostura (cusparia bark), anise, apricot kernel (persic oil), asafetida, balm (lemon balm), balsam (of Peru), basil, bay leave, bay (myrcia oil), bergamot (bergamot orange), bois de rose (Aniba rosaeodora Ducke), cacao, camomile (chamomile) flowers, cananga, capsicum, caraway, cardamom seed (cardamon), carob bean, carrot, cascarilla bark, cassia bark, Castoreum, celery seed, cheery (wild bark), chervil, cinnamon bark, Civet (zibeth, zibet, zibetum), ceylon (Cinnamomum zeylanicum Nees), cinnamon (bark and leaf), citronella, citrus peels, clary (clary sage), clover, coca (decocainized), coffee, cognac oil (white and green), cola nut (kola nut), coriander, cumin (cummin), curacao orange peel, cusparia bark, dandelion, dog grass (quackgrass, triticum), elder flowers, estragole (esdragol, esdragon, estragon, tarragon), fennel (sweet), fenugreek, galanga (galangal), geranium, ginger, grapefruit, guava, hickory bark, horehound (hoarhound), hops, horsemint, hyssop, immortelle (Helichrysum augustifolium DC), jasmine, juniper (berries), laurel berry and leaf, lavender, lemon, lemon grass, lemon peel, lime, linden flowers, locust bean, lupulin, mace, mandarin (Citrus reticulata Blanco), marjoram, mate, menthol (including menthyl acetate), molasses (extract), musk (Tonquin musk), mustard, naringin, neroli (bigarade), nutmeg, onion, orange (bitter, flowers, leaf, flowers, peel), origanum, palmarosa, paprika, parsley, peach kernel (persic oil, pepper (black, white), peanut (stearine), peppermint, Peruvian balsam, petitgrain lemon, petitgrain mandarin (or tangerine), pimenta, pimenta leaf, pipsissewa leaves, pomegranate, prickly ash bark, quince seed, rose (absolute, attar, buds, flowers, fruit, hip, leaf), rose geranium, rosemary, safron, sage, St. John's bread, savory, schinus molle (Schinus molle L), sloe berriers, spearmint, spike lavender, tamarind, tangerine, tarragon, tea (Thea sinensis L.), thyme, tuberose, turmeric, vanilla, violet (flowers, leaves), wild cherry bark, ylang-ylang and zedoary bark.
Suitable synthetic flavoring substances and adjuvants are listed in the Code of Federal Regulations (CFR) Title 21 of the United States Food and Drug Administration, Department of Health and Human Services, Part 180.60, which is hereby incorporated by reference. These GRAS materials may be present in the compositions in amounts of up to about 1% by weight, preferably in amounts of 0.01 and 0.5% by weight.
Suitable synthetic flavoring substances and adjuvants that are generally recognized as safe for their intended use, include acetaldehyde (ethanal), acetoin (acetyl methylcarbinol), anethole (parapropenyl anisole), benzaldehyde (benzoic aldehyde), n-Butyric acid (butanoic acid), d- or l-carvone (carvol), cinnamaldehyde (cinnamic aldehyde), citral (2,6-dimethyloctadien-2,6-al-8, gera-nial, neral), decanal (N-decylaldehyde, capraldehyde, capric aldehyde, caprinaldehyde, aldehyde C-10), ethyl acetate, ethyl butyrate, 3-Methyl-3-phenyl glycidic acid ethyl ester (ethyl-methyl-phenyl-glycidate, so-called strawberry aldehyde, C-16 aldehyde), ethyl vanillin, geraniol (3,7-dimethyl-2,6 and 3,6-octadien-1-ol), geranyl acetate (geraniol acetate), limonene (d-, l-, and dl-), linalool (linalol, 3,7-dimethyl-1,6-octadien-3-ol), linalyl acetate (bergamol), methyl anthranilate (methyl-2-aminobenzoate), piperonal (3,4-methylenedioxy-benzaldehyde, heliotropin) and vanillin.
Suitable GRAS substances that may be present in the inventive compositions that have been identified as possibly migrating to food from cotton, cotton textiles, paper and paperboard materials used in dry food packaging materials are listed in the Code of Federal Regulations (CFR) Title 21 of the United States Food and Drug Administration, Department of Health and Human Services, Parts 180.70 and 180.90, which are hereby incorporated by reference. The GRAS materials may be present in the compositions either by addition or incidentally owing to migration from the substrates to the compositions employed in the invention, or present owing to both mechanisms. If present, the GRAS materials may be present in the compositions in amounts of up to about 1% by weight.
Suitable GRAS materials that are suitable for use in the invention, identified as originating from either cotton or cotton textile materials used as substrates in the invention, include beef tallow, carboxymethylcellulose, coconut oil (refined), cornstarch, gelatin, lard, lard oil, oleic acid, peanut oil, potato starch, sodium acetate, sodium chloride, sodium silicate, sodium tripolyphosphate, soybean oil (hydrogenated), talc, tallow (hydrogenated), tallow flakes, tapioca starch, tetrasodium pyrophosphate, wheat starch and zinc chloride.
Suitable GRAS materials that are suitable for use in the invention, identified as originating from either paper or paperboard stock materials used as substrates in the invention, include alum (double sulfate of aluminum and ammonium potassium, or sodium), aluminum hydroxide, aluminum oleate, aluminum palmitate, casein, cellulose acetate, cornstarch, diatomaceous earth filler, ethyl cellulose, ethyl vanillin, glycerin, oleic acid, potassium sorbate, silicon dioxides, sodium aluminate, sodium chloride, sodium hexametaphosphate, sodium hydrosulfite, sodium phospho-aluminate, sodium silicate, sodium sorbate, sodium tripolyphosphate, sorbitol, soy protein (isolated), starch (acid modified, pregelatinized and unmodified), talc, vanillin, zinc hydrosulfite and zinc sulfate.
Water
When the composition is an aqueous composition, water can be, along with the solvent, a predominant ingredient. The water should be present at a level of less than 99.9%, more preferably less than about 99%, and most preferably, less than about 98%. Deionized water is preferred. Where the cleaning composition is concentrated, the water may be present in the composition at a concentration of less than about 85 wt. %.
Cleaning Substrate
The cleaning composition may be part of a cleaning substrate. A wide variety of materials can be used as the cleaning substrate. The substrate should have sufficient wet strength, abrasivity, loft and porosity. Examples of suitable substrates include, nonwoven substrates, wovens substrates, hydroentangled substrates, foams and sponges and similar materials which can be used alone or attached to a cleaning implement, such as a floor mop, handle, or a hand held cleaning tool, such as a toilet cleaning device. The terms “nonwoven” or “nonwoven web” means a web having a structure of individual fibers or threads which are interlaid, but not in an identifiable manner as in a knitted web. Nonwoven webs have been formed from many processes, such as, for example, meltblowing processes, spunbonding processes, and bonded carded web processes.
Methods of Use
The present invention is directed to method for cleaning a hard surface with a natural composition. A “natural composition” is generally defined where at least 95% (more preferred, at least 97%, even more preferred 98% and most preferred at least 99%) of the components of the composition come from natural sources. In one embodiment, the present invention involves contacting the hard surface with a natural composition wherein the composition consists essentially of: 0.5-5% alkyl polyglucosde, 0.5-5.0% ethanol, 0.05-0.4% D-limonine or lemon oil, no less 0.2% builder, water, and optionally dyes, presevatives or colorants. The method of use may work with any of the compositions disclosed in the present invention.
EXAMPLES
The compositions are simple, natural, high performance cleaning formulations with a minimum of essential natural ingredients. Competitive cleaners are either natural and inferior in performance or contain additional ingredients that make them non-natural, such as synthetic components. Because preservatives, dyes and colorants are used in such small amounts, these may be synthetic and the entire composition may still be characterized as natural. Preferably, the compositions contain only natural preservatives, dyes, and colorants, if any.
Table I illustrates all purpose cleaners of the invention. Table II illustrates glass cleaners of the invention. Table III illustrates additional cleaning compositions of the invention. Table IV shows that the compositions of the invention give equivalent performance to commercial non-natural, or synthetic cleaning compositions, and superior performance to commercial natural cleaning compositions. Table V illustrates additional cleaning compositions of the invention.
TABLE I
All Purpose
Cleaner
A
B
C
D
E
F
Glucopon ®
2.24
3.00
1.00
5.00
1.50
3.00
425N 1
Ethanol
1.16
3.00
0.50
5.00
1.50
1.50
Glycerol
0.22
0.30
0.10
1.00
0.50
0.30
Lemon oil
0.22
0.30
0.10
0.40
0.20
Essential oil w
0.25
D-Limonene
Essential Oil
Preservative
0.005
None
0.002
0.001
0.01
0.005
and Dye
Sodium
0.15
0.10
Carbonate
Water
balance
balance
balance
balance
balance
balance
1 Coco glucoside from Cognis.
TABLE II
Glass Cleaner
G
H
I
J
K
L
Glucopon ®
0.60
1.50
0.30
0.50
0.50
1.00
425N
Ethanol
2.00
3.00
1.50
0.50
1.00
2.00
Glycerol
0.11
0.20
0.05
0.05
0.10
0.20
Lemon oil
0.20
0.05
0.05
Essential oil w
0.05
0.10
0.15
D-Limonene
Preservative
0.005
0.005
0.005
0.005
0.005
0.005
and Dye
Sodium
0.07
0.20
0.05
0.15
0.15
Carbonate
Water
balance
balance
balance
balance
balance
balance
TABLE III
All Purpose
Cleaner
M
N
O
P
Glucopon ® 215 1
2.00
2.00
Glucopon ® 225 2
1.50
Glucopon ® 325 3
0.50
Glucopon ® 600 4
Ethanol
1.00
1.00
1.00
2.00
Glycerol
0.20
0.20
0.10
0.15
Lemon oil
0.10
0.20
D-Limonene
0.15
Essential oil with
0.20
d-limonene
Preservative and
0.005
0.005
0.005
0.005
Dye/Colorant
Sodium
0.50
Bicarbonate
Sodium
0.05
0.05
Hydroxide
Sodium Silicate
0.05
0.05
Water
balance
balance
balance
balance
1 Capryl glucoside from Cognis.
2 Decyl glucoside from Cognis.
3 C9-C11 glucoside from Cognis.
4 Lauryl glucoside from Cognis.
TABLE IV
ASTM
Filming
Streaking
Cleaner
Bathroom
Mirrors
Mirrors
Formula A
Basis
Lysol ® Antibacterial Spray
equal
Seventh Generation ® Natural
less
Citrus Cleaner and Degreaser
Method ® All Purpose Surface
less
Cleaner
Formula G
Basis
Basis
Windex Vinegar Multisurface
Equal
equal
Seventh Generation ® Free and
less
equal
Clear Glass and Surface Cleaner
Method ® Window Wash Glass
equal
less
and Surface Cleaner
TABLE V
Cleaner
Q
R
S
T
U
V
Glucopon ®
3.00
3.00
3.00
3.00
2.75
3.25
425N 1
Ethanol
3.00
3.00
2.00
2.00
3.00
2.50
Glycerol
0.20
0.20
0.11
Lemon oil
0.30
Essential oil w
0.20
D-Limonene
Essential Oil
0.25
Preservative
0.01
0.02
0.01
0.01
0.02
and Dye
Sodium
0.1
Carbonate
Water
balance
balance
balance
balance
balance
balance
Without departing from the spirit and scope of this invention, one of ordinary skill can make various changes and modifications to the invention to adapt it to various usages and conditions. As such, these changes and modifications are properly, equitably, and intended to be, within the full range of equivalence of the following claims.
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A cleaning composition with a limited number of natural ingredients contains alkyl polyglucoside and ethanol. The cleaning composition optionally contains glycerol. The cleaning composition optionally contains essential oil. The cleaning composition optionally has a small amount of buffer, such as a natural inorganic buffer. The cleaning composition can be used to clean hard surfaces and cleans as well or better than commercial compositions containing synthetically derived cleaning agents.
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REFERENCE TO CO-PENDING APPLICATION
This is a continuation-in-part of U.S. patent application Ser. No. 08/156,428 filed Nov. 23, 1993, and abandoned in favor of this application.
FIELD OF INVENTION
Pulse dampers for electric fuel pumps using a rotary pump and electric drive housed together for mounting on a vehicle or in a vehicle fuel tank.
BACKGROUND OF THE INVENTION
Rotary fuel pumps driven by an electric motor have been utilized for some years in some vehicles either as original equipment or as appliances to supplement the original fuel supply system. The pump and power unit are frequently in a common housing as shown, for example, in U.S. Pat. No. 4,401,416, issued Aug. 30, 1982 to Charles H. Tuckey.
Since the pumps are frequently mounted in the fuel tanks of a vehicle, the noise factor is extremely important. A pump under load will normally produce more noise and this may be audible as a humming noise, to an annoying degree, to passengers in the vehicle.
It will be appreciated that in the pumping cycle, as one pumping cell is exhausting, another cell is taking in fluid at the same time. In other words, intake and exhaust pressure waves are timed with one another, and normally the quantity of fluid being exhausted from each cell is the same as that being taken in by another cell. It has been noted that pressure waves or pulses are present at the inlet, as well as the outlet, at all operating pressures.
It is an inherent characteristic of a positive displacement pump to produce slight pressure pulses each time one of the multiple vanes passes through its pumping cycle. For example, a roller vane rotary pump produces an audible humming noise when operating at system pressure. This noise has a tendency to increase as the output pressure requirement is increased.
One must acknowledge and deal with the extreme pressure differential between the inlet and exhaust sides of the pump. For instance, the inlet zone is usually at an average pressure close to atmospheric; and the outlet zone average pressure is much higher, i.e., 60 psig or more depending upon the operating pressure requirement of the pump.
It has been a desire of manufacturers and users of positive displacement rotary pumps to reduce or eliminate pressure pulses in order to achieve a smooth, pulse-free flow of fluid out of a pump at desired operating pressure.
Hollow pulse absorbing chambers in fuel pumps have been proposed previously as exemplified in U.S. Pats. to Yoshifumi, No. 4,181,473, issued Jan. 1, 1980 and to Tuckey, No. 4,521,164, issued Jun. 4, 1985. U.S. Pat. No. 5,035,588 issued Jul. 30, 1991 to Charles H. Tuckey discloses a hollow pulse modulator of a flexible plastic material formed by a blow molding process which has air trapped therein.
SUMMARY OF INVENTION
The present invention is directed to hollow toroidal pressurized pulse modulator mounted in a fuel pump. The modulator is disposed between the pump outlet exhaust zone and the outlet fitting of the pump. Thus, each time a pressure peak occurs in the exhaust fluid, the pressure compresses the resilient member, thereby reducing the pressure pulses at the outlet of the pump.
Preferably, a hollow, toroidal pressurized element is positioned in a pump housing in a pump outlet area. A centering plate is provided to partially surround the element with spaced radial fingers formed around the periphery of the toroid to confine it against undue expansion. The center of the plate locates the toroid centrally in the pump housing.
In the use of pressurized toroidal pulse modulators, it has been found that the flexible toroids may have a tendency to expand or balloon during inactivity of the pump which decreases their useful life and may cause interference with the pumping mechanism located on each side of the modulator. Thus, the modulator is received in a retainer which reduces flexing of its wall without inhibiting its performance.
An object of the present invention is to cause the exhaust pressure peaks to be modulated and create a smooth flow out of the assembly and at the same time reduce the pump noise. Another object of the invention is to provide a modulator mounting locator, centering and expansion limiting retainer which will limit the expansion without inhibiting the pulse reducing function intended for it. The retainer reduces flexing of the walls of the modulator and extends the fatigue life significantly.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the invention will be apparent from the following detailed description of the preferred embodiment and best mode, appended claims, and accompanying drawings in which the various views may be briefly described as:
FIG. 1 is a sectional view of an electric fuel pump incorporating the pulse damper and retainer of the present invention.
FIG. 2 is an elevational view of the toroidal pulse damper.
FIG. 3 is a view of a retainer sheet blank prior to assembly.
FIG. 4 is a view of the formed and assembled retainer and toroidal pulse damper prior to installation in a pump.
FIG. 5 is a sectional view of an electric pump incorporating the pulse damper and a modified retainer of the present invention.
FIG. 6 is a view of the assembled modified retainer and toroidal pulse damper prior to installation in the pump.
DETAILED DESCRIPTION
With reference to the drawings, FIG. 1 illustrates an electric fuel pump with an inlet housing 10 and an outlet housing 20 separated by a cylindrical field casing 22. An encompassing case cover 24 with O-ring seals at each end has ends 26,28 spun over the housings 10 & 20 to unify the assembly. Armature magnets 30 and 32 are disposed in a conventional way around a rotating armature 40 which has a commutator 42. Brushes 44 and 46 in outlet housing 20 are resiliently pressed against the face of the commutator 42 with suitable electrical connectors 48 and 50.
The armature 40 has a mounting shaft 60 journalled in a boss 62 formed in a wall 64 of the inlet housing 10. An inlet port 65 in the wall admits fuel to the inlet side of the pump which comprises an inner gear rotor 66 pressed on and permanently affixed to the shaft 60 and positioned within an outer gear rotor 68. A pump outlet port 69 is provided but pump outlet fuel may also pass around the flexible seal 70 which is free to rotate with the outer gear 68 and is pressed against the rotors by an eyelet 72 mounted between the armature and the seal. The gear teeth on the rotors 66 and 68 are preferably meshed helical gears, as described more fully in U.S. Pat. No. 4,596,519, dated Jun. 24, 1986, to reduce and smooth out pulsations in the pump output.
At the other end of armature 40, a mounting shaft 80 is journalled in a pressed-on bushing 82 in a central insert 84 in the outlet housing 20. The bushing 82 is affixed to the shaft 80 and is axially movable in the insert in a recess 85. A small vent 86 is provided at the end of the recess 85. The bushing 82 rotates with the shaft 80. An outlet nipple connection 87 is provided in a conventional way. A filter screen 88 extends over the basic opening 90 in the inlet housing 10. The inlet 10 has an inwardly extending flange 94 facing the armature magnets 30,32.
In accordance with this invention, an annular pulse damper 100 is received in a retainer 102 disposed in the housing between the inlet flange 94 and the armature magnets 30 & 32. The damper is in the shape of a toroid or doughnut with an open center and a hollow interior which is filled with a gas such as air at a superatmospheric pressure which is typically in the range of about 40 to 45 psig. Both circumferentially and in cross-section, the damper has a continuous wall and is formed as a sealed chamber preferably in a blow molding process in which the pressure of the interior enclosed gas is made superatmospheric. The interior pressure is predetermined and selected to relate to the operating pressure of the fuel discharged from the pump in which the damper is installed. Preferably, the damper is formed of a flexible plastic material resistant to hydrocarbons and alcohols such as ACETAL™.
Due to its relatively higher internal pressure, when the damper is unrestrained and disposed in the atmosphere, it has a cross-section which is elliptical to substantially circular. However, when in the pump and while the pump is operating, the exterior of the damper is in contact with liquid fuel at a sufficiently higher pressure so that in cross-section, the damper has a generally oval configuration as shown in FIG. 1 with two generally flat elongate portions interconnected by generally opposed return bend portions in what might be called a generally racetrack configuration. As the pump is turned off and on, the pressure of the fuel on the exterior of the damper varies about 0 psig to a maximum operating pressure of the pump which is usually in the range of about 45 to 60 psig. This pressure variation would cause substantial flexing and displacement of the damper wall from a substantially circular cross-section to the racetrack cross-section if the damper were not restrained in the racetrack configuration by the retainer. This substantial flexing would significantly increase the stressing of the material of the damper, thereby greatly reducing its in-service useful life due to fatigue failure of the material. Moreover, in the close confinement of the housing between the pump and the motor, the damper could contact and interfere with the adjacent parts of the pump and the motor if it were not restrained by the retainer.
The retainer 102 is preferably stamped from a flat blank of sheet metal having at least some inherent resilience (such as spring steel) but still being sufficiently malleable that it may be formed into a relatively complex shape and will retain its shape as formed. The stamped blank has a central body 120 with a locating center hole 122 and around its periphery a plurality of equally circumferentially spaced radial fingers 124 with free ends which are preferably rounded. Preferably, at the base of each finger is a widened tab 126 extending from the central body 120 and a notch portion 130 between each tab which extends to the basic circumference of the body 120. Preferably, the edges of the fingers, tabs and notches of the blank are brushed or otherwise processed so that they do not have any sharp areas or burrs which might cut into, wear away or damage the wall of the damper during the flexing of the damper resulting from pulsations and pressure changes in the output of the fuel from the pump. Preferably, as shown in FIG. 1, the fingers and tabs are bent at an acute included angle to the plane of the base or central body 120 which is preferably about 15° to 35°.
After the toroidal damper 100 is centered over the blank with its outer diameter lying in the vicinity of the dot-dash line A in FIG. 3, then the fingers 124 are bent around the outer periphery of the damper (as shown in FIG. 4) so that in cross-section, it has the oval or racetrack configuration shown in FIG. 1. The bight 132 of each finger is formed around the outer diameter of the toroidal damper with a return bend so that the free end of the finger overlies and preferably extends generally parallel to base portion of the finger and its associated tab 126. Preferably, as shown in FIG. 1, the tip of the free end of each finger is bent so that it is somewhat upturned away from the underlying wall of the damper. Preferably, the upturned finger tip may be formed simultaneously with bending the tab 126 and finger to their inclined position relative to the plane of the base or the central portion of the body 120 of the retainer.
In use, the inherent resilience of the confining fingers combines with the resilience of the toroidal damper to complement and enhance the absorption and dissipation of fuel pulses by the combined damper and retainer.
After the retainer blank has been positioned and formed around the pulse damper 100, as shown in FIG. 4, it is ready to be assembled with the other elements of the pump. The hole 122 in the retainer body fits over the eyelet 72 mounted between the pump armature and the seal 70. The outer periphery of the pulse element is positioned between the magnets 30 & 32, on one side, and the inner edge of the flange 94 on the other side.
FIG. 5 illustrates the electric fuel pump with a modified retainer 102' receiving and mounting the pulse damper 100 in the pump. The retainer and pulse damper are mounted in the casing 22 by being trapped between the inlet flange 94 and the armature magnets 30 and 32. As shown in FIG. 6, the modified retainer 102' has a central through hole 122' with a diameter which is larger than the outside diameter of the eye or bushing 72. This provides an annular space between them through which fuel can flow and isolates the bushing 72 from the retainer to insure that the retainer will not laterally displace the bushing so that it is not concentric with the axis of rotation of the armature shaft 60. Except for this enlarged central hole 122', the retainer 102' has the same construction and arrangement as the retainer 102.
In operation of the pump, the spaced fingers 124 and the tabs 126 of the retainer confine the flexible toroid damper to prevent undue expansion while allowing the required contraction and expansion during pump operation needed to dampen and absorb pulsations in the fuel discharged from the pump. When the pump is shut off, the retainer also prevents excessive flexing and movement of the damper into a circular cross-section with resulting contact and interference with adjacent parts of the pump and motor of the fuel pump assembly. The locating and retention plate significantly extends the life of the pulsing damper without interfering with its basic function and indeed enhancing its performance.
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A damper in a self-contained electrically operated fuel pump for vehicle engines incorporating a positive displacement pumping element. The damper has a hollow toroidal flexible element in contact with the liquid fuel discharged from the pump for absorbing pulsations. A retainer with a locating plate on one side of the damper centers it in the pump housing and has resilient circumferentially spaced, radial fingers extending over and around the periphery of the toroid to confine it against destructive expansion while permitting limited expansion and contraction needed to absorb fuel pressure pulsations in pump operation.
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DESCRIPTION OF THE PRIOR ART
The present invention is directed to hangers for holding brassieres and a display unit which supports a large number of the hangers and thereby the brassieres.
Retail stores which carry women's undergarments are generally known to provide stand alone display units which display a large number of brassieres on hangers. The typical hanger has two arms which extend horizontally away from each other and a hook extending vertically upward from between the arms. Each free end of the arm also has a hook which extends downward, on which is wrapped a shoulder strap of the brassiere.
A display unit in a retail store typically has extension rods which extend outward from a vertically extending base at different elevations. Each extension rod holds a finite number of hangers. The separation distance between the different levels must be at least the same size as the hanging distance of the hanger with brassiere. By maintaining such a separation distance, placing and removing the hangers on the extension rods is done without interference from an extension rod that is immediately beneath.
Hanging the brassiere on the typical hanger requires wrapping the shoulder strap around the ends of the horizontally extending hanger arms and securing the strap by fastening hooks at these ends. This is done to minimize the slack which would otherwise be evident from hanging and to ensure that the brassiere stays on the hanger.
The fastening hooks extend outside of the hanger arms, such as in the direction of elongation of the hanger arm on either side of the extension rod and also downward in a direction perpendicular to this direction of elongation. Each of these fastening hooks has a resilient extension which projects back in the opposite direction from which the rest of the fastening hook extends. Shoulder straps of the brassiere are held resiliently by the resilient extension of at least one of these fastening hooks at each end of the hanger. Such a prior art hanger is exemplified in U.S. Pat. No. 4,623,079. Due to the narrowness of such hanger arms, the shoulder straps must be wrapped around the hanger arms a large number of times to take up slack.
It would therefore be desireable to hang a brassiere on a hanger to both maintain a neat appearance and yet limit the number of times the shoulder straps must be wrapped around the hanger arms for obtaining an acceptable minimal amount of slack and to increase the number of units of hangers with brassieres which may be hung by a display unit.
SUMMARY OF THE INVENTION
The present invention is directed to a hanging arrangement which includes a hanger. The hanger has a central portion and two elongated hanger arms which extend away from the central portion. The central portion has an inner facing side which defines a space. The arms each have means for holding shoulder straps of a brassiere in position against the arms so as to avoid relative movement of the shoulder straps where held with respect to the arms. The inner facing side has a portion at an elevation which is higher than where the shoulder straps of the brassiere are to be held by said holding means against the arms. The arms each have a face with a predetermined width so that if said faces are each projected through the space to intersect each other as would occur by further elongating the hanger arms toward each other, the portion of the inner facing side lies within said widths of the faces as projected. The space is adapted to accommodate a support member inserted therein, such as an extension rod, so that the portion of the side may rest against the support member.
The present invention is further directed to hanging a brassiere from the hanger. Preferably, each of the arms have a slot and clip in alignment with each other which extend in the direction of elongation of the arms. Shoulder straps of the brassiere are resiliently held by the clips against the arms, respectively. The shoulder straps are wrapped around the arms, respectively, twice. If the hanger is rotated once relative to the brassiere, then the cups of the brassiere reach a face of the hanger.
The hangers may be supported by respective extension rods which project from a vertically extending base. Each extension rod is against an underside of an area of the portion of the inner facing side of a respective hanger arm. The hanger then balances on the extension rod at this area. The extension rods are at different elevations; the spacing between the extension rods at adjacent levels is equal to the full hanging length of the hanger with brassiere hanging from the hanger arms.
The ratio of the width and thickness of each hanger arm is greater than 2:1, preferably 15:1. Preferably, an elevation of the area of the portion of the inner facing side of the central portion is at most one inch higher than an uppermost elevation where said the shoulder straps are to be held in position against the arms by the holding means.
In order to vary the number of hangers which may be held by any one extension rod, the extension rod may be telescoping in which a rod is slidable back and forth in an elongated hollow housing.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, reference is made to the following description and accompanying drawings while the scope of the invention will be pointed out in the appended claims.
FIG. 1 shows an elevational view of a display unit with hangers holding brassieres in accordance with the prior art.
FIG. 2 shows an elevational view of a display unit having the same vertically extending base as the display unit of FIG. 1, but with hangers in accordance with the present invention which hold brassieres on a greater number of extension rods in accordance with the present invention.
FIG. 3 shows a front side elevational view of the hanger in accordance with the present application.
FIG. 4 shows a partial front perspective view of the hanger of FIG. 3 from which is hung a brassiere.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning to the drawings, FIG. 1 shows a conventional display unit 10 which has a vertically elongated base 12 from which project extension rods 14 at different elevations from all four sides of the base 12. The extension rods 14 are spaced apart from each other and support conventional hangers 20, each of which support a brassiere 30. Shoulder straps 32 are wrapped around an end 22 of the hangers and held by resilient fastening hooks 34 to reduce the amount of slack present during hanging. Each end has three resilient fastening hooks; two extend on either side of the respective hanger arm in the direction of elongation of the hanger arm and the third fastening hook extends downward perpendicular to the other two.
The spacing between each level of extension rods 14 is sized to accommodate a hanger with brassiere hanging therefrom without creating any interference with extension rods beneath each level. The extension rods 14 are releasably securable into any one of a number of locking positions in the track 16 of the base 12. The base 12 rests on a base 18 and is capped by a dome 24. The free ends of the extension rods have balls attached thereto to provide a smooth end for safety reasons.
The display unit 10 may be made from any type of material, preferably metal, wood or a sturdy plastic. The top of the display unit is capped by a dome 24 which may be made from a colored translucent material and houses a light for illuminating the display. Illumination may also be provided vertically behind colored translucent strips which extend the height of the base 12 along each of the corners and face toward where the hangers are to be hung.
The extension rods 14 may be secured in position along track 16 in any number of known ways, such as by fastening screws which fit into holes in the track and through a support 15 which holds the extension rod 14.
FIG. 2 shows the same display unit 10 as in FIG. 1, except that the hanger 60 of FIGS. 3-4 is employed in accordance with the present invention. By using the hanger 60 of the present invention, more space becomes available between the levels of hangars, thereby enabling more hangers to be arranged vertically one over the other in the same space than is possible in the conventional display unit 10 of FIG. 1.
The hanging height of a hanger with brassiere has been found to be, respectively, 12 inches for the CAMEO 2380 size 34B bra and 121/2 inches for the CAMEO 2380 size 34D bra with a conventional hanger 20 as in FIG. 1 is employed. Surprisingly, the hanging height for these two units was reduced to 8 inches and 93/4 inches, respectively, when the hanger 60 of FIGS. 3-4 was employed instead of the conventional hanger 20.
The number of units (hangers with brassieres) which may be accommodated as between the display units and hangers of FIGS. 1 and 2 is 40 to 60 percent more with hangers of the present invention as opposed to that for conventional hangers. The following table is illustrative:
______________________________________ Total number PercentageHanger Display Size of units increaseof Height Bra held with FIG. 2______________________________________FIG. 1 59" 36D 96FIG. 2 59" 36D 144 50FIG. 1 59" 34B 120FIG. 2 59" 34B 168 40FIG. 1 64" 34B 120FIG. 2 64" 34B 192 60______________________________________
If desired, space for additional hangers may be provided by employing telescoping extension rods.
FIGS. 3-4 show a hanger 60 of uniform thickness for holding brassieres in accordance with the present invention, except that each elongated tong or clip 48 can be considered to be a cut out from a respective hanger arm 40 to form an elongated slot 46. Hanger 60 actually has two hanger arms 40 which extend from an interconnecting portion 42. Each hanger arm has a face which defines a width of the hanger arms and extends in a common plane with each other.
There is a hook 44 which is higher than the hanger arms and extend from at most one of the arms. The interconnecting portion 42 and hook 44 may together be considered a central portion which defines a space or opening 50. Preferably, the hanger arms incline downward and away from the interconnecting portion 42, so as to avoid the tendency for the hanger 60 to otherwise topple if the hook 44 were lower relative to the hanger arms 40.
Each hanger arm 40 has a respective elongated slot 46 and a respective elongated clip 48 extending along the length of the slot 46 but behind the slot 46. The clip 48 is secured to the respective hanger arm 40 by a lower end of the slot and has the shape of the slot 46. Since the clip 48 has a distant free end, it is somewhat resilient for accommodating a wrapping of shoulder straps of a brassiere 30 as shown in FIG. 4. The clip 48 presses against these straps to secure them in position. Preferably, clip 48 and slot 46 conform in shape to each other; the clip 48 may be a cut out of the slot 46. Both the clip 48 and slot 46 are preferably in alignment with each other. The clip extends preferably adjacent to an end of the elongated slot 46.
At the far end of each hanger arm are grooves 52 between which may be stretched panties which are thereby held. The interconnecting portion 42 defines a space 50 in which may be fit a respective extension rod 14 from the base 12 via a gap 54 between the hook 44 and one of the hanger arms 40.
By arranging the hook 44 to lie within projected widths of faces of the hanger arms (as may be envisioned if the hanger arms are projected to intersect each other so as to further extend the hanger arms far enough toward each other to intersect), a savings of about 11/4 in height is realized over the conventional hanger. Preferably, the distance between the uppermost location where the shoulder straps are held to the arms and the area on the hook 44 which will lie against the extension rod 14 is less than one inch so as to minimize the upward projection of the hook 44 and still ensure stability of the hanger.
Further savings in the overall hanging height is realized by the manner in which the brassiere is hung on the hanger 60 in accordance with the present invention as compared to that for the prior art. This involves contributions from the wider and inclined hanger arms and the resilient clips which allow the brassiere to hang closer to the hanger than on the prior art hangers. The large area which comprises the interconnecting portion 42 helps to stabilize the hanger on the extension rod and serves as a guide around which the brassiere is to hang.
By extending the hook 44 to lie within the projected widths of the faces of the hanger arms, the distance to which the hook 44 extends relative to where the brassieres are to be hung may be kept a minimum. Gap 54 enables store personnel or customers to quickly remove a selected hanger and brassiere unit off an extension rod.
If all the brassieres being hung from any one extension rod are identical, there is no need for gap 54, because customers may pull off the hangers in succession over the free end of the extension rod 14. Therefore, the hook 44 may be extended to fill in this gap 54 so that the hook 44 in effect interconnects the hanger arms with each other. With such a configuration, even the interconnecting portion 42 may be dispensed with, although retaining the interconnecting portion 42 provides advantages such as greater stability against toppling and as a barrier between the brassiere and the extension rod.
As can be seen in FIG. 4, clips 48 resiliently press the shoulder straps 32 against the hanger arms 40. Wrapping is effected by inserting the shoulder strap between the clip 48 and extension rod 40, wrapping the shoulder strap entirely around the hanger arm to return to between the clip 48 and extension rod 40. Thus, the shoulder strap is looped once around the hanger arm so that the beginning and end of the loop is held by the clip. The shoulder strap is wrapped again to hang freely.
Preferably, one of the clips 36 on the shoulder strap 32 and a ring 38 on the shoulder strap 32 are on either side of the clip 48 to help clamp the shoulder strap 32 in place between the clip 48 and hanger arm 40. While not absolutely necessary, one full rotation of the hanger relative to the hanging brassiere will bring the cups of the brassiere against a face of the hanger so as to reduce the overall hanging distance even further and yet maintain a neat appearance.
The preferred width or height of each of the hanger arms is about 11/4 inches or more to minimize the number of times the shoulder straps need be wrapped around the hanger arms to minimize slack. Conventional hangers as in FIG. 1 have a width of less than 3/8 inches--at least four times smaller than the preferred height of the hangers in accordance with the present invention. Thus, the shoulder straps are wrapped four times more around the hanger arm with the conventional hanger to take up the same amount of slack as can be obtained by a single rotation of the hanger in accordance with the preferred embodiment of the present invention. If the total perimeter of the hanger arms are considered across the faces and sides (where the shoulder straps are to be wrapped), the perimeter of the hanger arms of FIG. 3 is 4 to 5 times greater than that of the hanger arms of FIG. 1. While this perimetrical distance is advantageous in allowing the brassiere to hang as shown in FIG. 4, any distance greater than that of the conventional hanger of FIG. 1 would also fall within the scope of the present invention.
The present invention therefore requires a fewer number of full wrappings of the shoulder straps around the hanger than is required for conventional hangers. The prior art hanger of FIG. 1 has a width to thickness ratio for its arms of less than 2:1 (if the width of outward projections at the bottom and top of the hanger arms are taken into account).
Preferably, the height of the hanger arms are each more than two times greater than the thickness of the hanger arms, i.e., at least 15 times to minimize the number of times the shoulder strap is wrapped around the hanger arms to two loops. If further reduction in overall hanging height is desired, the hanger need only be rotated once from this position relative to the brassiere to cause the cups of the brassiere to lie against the hanger.
Prior to shipment, such a hanger may be quickly wrapped by the shoulder straps by looping the straps twice around each of the arms and underneath the clips, respectively. The resilient force of the clips 48 will prevent the brassiere 30 from falling off during shipment.
For the sake of brevity, the reverse side of FIG. 3 is not shown in a separate drawing, but its surface is flat and appears essentially identical to that of FIG. 3, except that slots 46 appear as wide as the clips 48 and the clips 48 are visible through the slots 46.
Preferably, the upper surfaces of the hanger arms which define the thickness of the hanger arms and extend in the direction of elongation of the hanger arms may be projected to intersect each other such that an uppermost side of the central portion lies within a prism which is constituted by the surfaces being projected to intersect each other and a plane which extends between ends of the surfaces from the free ends of the hanger arms.
Further, the hanger arms may extend at oblique angles relative to each other so as to substantially conform in shape to a lower edge of a brassiere hanging from an identical hanger.
While the foregoing description and drawings represent the preferred embodiments of the present invention, it will be understood that various changes and modifications may be made without departing from the spirit and scope of the present invention.
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A hanging arrangement which includes a hanger. The hanger has a central portion and two elongated hanger arms which extend away from the central portion. The central portion has an inner facing side which defines a space. The arms each hold shoulder straps of a brassiere in position against the arms so as to avoid relative movement of the shoulder straps where held with respect to the arms. The inner facing side has a portion at an elevation which is higher than where the shoulder straps of the brassiere are to be held against the arms. The arms each have a face which extends in a common plane. The faces each have a predetermined width so that if said faces are each projected through the space to intersect each other as would occur by further elongating the hanger arms toward each other, said portion of the inner facing side lies within said widths of the faces as projected. The space is adapted to accommodate a support member inserted therein so that the portion of the side rests against the support member.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to composite abrasive products or elements comprising an active part formed by a "compact" having a polycrystalline structure and containing grains of ultra-hard material bonded directly together and a hard and refractory carbide support having a metallurgical bond with the compact.
The term "compact" designates a cemented product formed by grains bonded together by bridges created by diffusion of material in plastic condition.
2. Prior Art
Composite cutting products of the above-defined type are already known in which the compact covers the whole of one face of the support or forms an embedded cutting edge (French Patent No. 2,089,415).
Products are also known formed of an annular compact of ultra-hard material (polycrystalline diamond or cubic boron nitride) carried by a face of a carbide support which is also annular (British Patent No. 1,473,664).
Finally, products are known in which the compact, in the form of a ring, is fixed by brazing or clamping in an annular recess of the support, this recess being defined by a surface perpendicular to the axis of the ring and by an internal surface parallel to the axis (European Patent No. 0,019,467).
According to European Patent No. 0,019,467, this arrangement is supposed to have the advantage of reducing the cost of the composite product by a rational use of the abrasive part, limited to a narrow useful peripheral zone extending along the cutting edge. It is true that this arrangement makes it possible to cut out, from the same starting compact, several concentric strips having the same shape and different diameters and locate them on different products by brazing or mechanical fixing. As in the case of the product defined in British Patent No. 1,473,664, advantage is taken of the fact that a composite product consisting of a layer of ultra-hard material is in fact only used along a peripheral strip along the cutting edge. The ultra-hard compact is however not fixed to its support by a metallurgical bond, which means that all the advantages provided by such a bond are lost.
It is impossible to form a true composite product (i.e. in which the compact is manufactured on the support itself and has a metallurgical bond therewith) when the annular compact occupies a recess of the support whose cross-section has a sharp angle. The reason is that the shrinkage of the compact during high temperature and high pressure sintering of a composite would create stresses causing cracking during cooling after sintering and during use of the product, under the effect of the thermal or mechanical stresses which then appear.
SUMMARY OF THE INVENTION
An object of the invention is to provide a composite abrasive product whose compact is annular, answering better than those known heretofore to the requirements of practice, particularly in that it makes it possible both to overcome the risk of breakage caused by the thermal stresses at the interface and to reduce the mass of ultra-hard material to a minimum.
For that purpose, the invention provides a composite abrasive product whose compact is in the form of a ring having a small axial thickness as compared to that of the support, with a cross-section approximately in the form of a triangle, generally elongated radially, one of the faces of the compact having a metallurgical bond with a chamfered circumferential portion of the support and the other faces ending in the cutting edge.
The dimensions of the chamfer and those of the compound are advantageously proportioned so that the composite has a flat surface perpendicular to the axis of the annular compact.
The term "annular" used above should not be interpreted as meaning that the compact has necessarily the shape of a complete ring. While, in most cases, particularly when the product has a shape of revolution, the compact effectively represents a complete ring, it may be otherwise, especially when the product has a prismatic shape. Then, the compact may be split up into several portions representing fractions of the ring, occupying the projecting portions of a prism.
Whatever the embodiment used, the presence of a single oblique surface, rather than two mutually orthogonal surfaces which create stress concentration zones, makes it possible to absorb the latter at a point such as to make it possible to secure the composite product by brazing and to use it without difficulty as a tool under heat producing conditions.
The angle between the surface of the product having the cutting edge and the face of the compact having a metallurgical bond (i.e. the interface between the polycrystalline compact and support) depends on the use. It is generally of from 3° to 45°. It is optimized as a function of the thickness of the ultra-hard compact desired and of the width of the useful peripheral band. This useful band varies depending on the application: on a product intended for machining, it is relatively narrow while, on a product forming a drilling insert, it is much wider.
Since the compact is annular, it is possible to make a composite product formed with a central connection hole without difficulty. In fact, it is sufficient to give the ring radial dimensions such that the hole to be formed does not extend onto the ultra-hard material compact.
Such a central hole is often extremely useful for passing a mechanical connection element therethrough on a tool holder (for example on a machining or cutting machine) or to accomodate a flow of cooling fluid, in the case of use for drilling. Machining the hole in the metal carbide support (tungstene carbide in general) presents no difficulty: it may be achieved by electroerosion. On the other hand, it is difficult to machine a hole through the whole of a compact and of the support of a composite abrasive product, since the abrasive product made from a ultra-hard product is a poor electric conductor and lends badly to electro-erosion cutting and the support is damaged in the case of laser cutting, suitable for the compact.
The invention also provides a method of manufacturing a composite abrasive product of the above-defined kind, in which: an annular layer of powder of the product intended to form the abrasive compact is placed on the periphery of the bottom of a cup and the layer is given a cross-section approximately in the form of an elongated triangle; a cemented carbide support having, on one face at least, a circumferential chamfer of a shape corresponding to that of the layer is placed on the layer; the annular layer is densified by mechanical pre-compacting; the cell containing the assembly is brought to a temperature exceeding 1200° C. under a pressure exceeding 45 kbar in a press and the cell is maintained at these temperature and pressure for a sufficient time to cause formation of a compact and of a metallurgical bond between the compact and the support.
To improve the bond between the polycrystalline compact and the support, a layer may be inserted therebetween forming a diffusion barrier and/or a thin film of a metal used as catalyst binder (for example cobalt or nickel/chromium). In addition, in order to avoid diffusion of the binder contained in the carbide. when a compact is used having a thermostable binder, it is advantageous to provide at the interface a layer of a refractory metal such as tungstene for example. In this case, the method described in European patent application No. 0,246,118 may in particular be used.
The invention will be better understood from the following description of particular embodiments, given by way of non-limitative examples.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 and 2 show schematically, in elevation with part cut away, the construction of two products in accordance with the invention, intended respectively to form a drilling insert and a cutting tool element;
FIG. 3 shows schematically the positioning of the components for forming a product of the kind shown in FIG. 1 for manufacture;
FIG. 4, similar to FIG. 2, shows an abrasive product which can be used as a cutting tool element, forming a modified embodiment of the invention;
FIG. 5, similar to FIG. 4, shows yet another modification; and
FIG. 6, similar to FIG. 3, corresponds to the manufacture of a product of the kind shown in FIG. 5.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The composite products shown in FIGS. 1 and 2 both comprise a support 10 of sintered refractory carbide, which will be assumed to contain cobalt as a sintering binder, and a compacts 12 of ultra-hard product having a metallurgical connection with the support. The ultra-hard product may particularly contain 80 to 95% by volume of diamond grains, bonded together directly by bridges. The empty spaces between the diamond grains are occupied by a binder phase which may be an element of the iron group known for its catalyst properties or, particularly when it is desired to obtain a thermostable product, compounds such as those described in document EP-A-0,246,188 already mentioned. The ultra-hard product may be cubic boron nitride (CBN) in substitution for diamond. The binder used in this case has an aluminium base, such as for example the binder described in document EP-A-0,181,258.
According to the invention, compact 12 is in the form of a ring with a triangular cross-section whose degree of elongation in the radial direction is selected particularly as a function of the use for which the product is intended. When it is intended to form a drilling insert (FIG. 1), the width of the ring will be a significant fraction of the radius of the product. In this case, the product will generally be used until there is considerable conical wear. Often, when a central hole 16 is required for passing a fixing bolt therethrough on a tool-holder such as a coalcutter or for allowing a cooling fluid to flow therethrough, the hole may occupy the whole of the radial space inside the annular compact. When the product is intended to be secured onto a machining tool-holder, the width of the ring and the degree of radial extension of the cross-section will in general be smaller (FIG. 2). The central hole 16, if it is provided, may leave a visible annular zone of the support on the face terminating in the cutting edge 18.
The following non-limitative examples correspond to products which have been manufactured and tested with good results.
EXAMPLE 1
A drilling insert of the kind shown in FIG. 1, having the following characteristics, was made:
Diameter: 19.05 mm
Height: 5 mm
Compact: of triangular section having a height of 1 mm and a width of 7 mm,
Support: tungsten carbide with an 8° chamfer.
To manufacture this insert, a layer 22 of a mixture formed of 92% by volume of diamond particles having a grain size between 12 and 22 μm and 8% of cobalt powder is placed at the periphery of the bottom of a molybdenum cup 20 (FIG. 3). On this layer is placed the support, formed by a stud 24 in the form of a chamfered cylinder, obtained by sintering of a mixture of 89% by weight of tungsten carbide having a grain size of about 5 μm and 11% cobalt. Stud 24 is pressed on the active part 22 so as to densify the powder layer between the chamfer and the wall of the cup. Cup 20, sealingly closed by a lid 26, is brought to 55 Kbars and 1500° C. for 4 mn to sinter the diamond, the pressure being maintained curing the temperature rise and fall. The cup is removed. The faces are ground and the composite product is trued. For a particular application, a central hole 16, of a diameter substantially equal to the internal diameter of the compact, was formed by electric discharge machining.
EXAMPLE 2
The same method as in Example 1 is used, except that a cobalt film 40 μm thickis disposed on the face of the stud in contact with the diamond powder. The degree of stress, evaluated by measuring the flatness of the annular "table" of the compact before and after cutting of the support in mid-height, is considerably reduced as compared with that of Example 1.
EXAMPLE 3
The same method as in Example 1 is used, except that:
layer 22 is formed of diamond particles of 10 to 60 μm, with a mean size of 40 μm;
a film for forming a diffusion barrier, 150 μm thick, formed by a mixture of 50% by volume of electromelted WC powder of a diameter of 80 μm and 50% by volume of diamond powder of 40 to 60 μm is interposed between layer 22 and pin 24.
No stripping of layers, no cracking was observed after the composite product had been subjected to a rapid heat gradient from 0° to 740° C., then air cooling.
EXAMPLE 4
A composite product intended to form a cutting plate was manufactured using the same process as in Example 1 with the following modifications:
Support forming stud:
Tungsten carbide cylinder, formed from 3 μm particles, with 8% cobalt wt., having, after shaping, a diameter of 13.05 mm and a chamfer at 14° giving a cutting height of 0.7 mm and a width of 2.8 mm for the compact.
Compact forming layer: 89% by volume of diamond powder of 5 to 8 μm and 11% cobalt.
Sintering at 57 kbar and 1550° C. for 3.5 mn.
The composite blank obtained by the method was cut by electro-erosion, then sharpened so as to give a plate of the kind shown in FIG. 4. It can be seen that only the four cutting edges are covered with sintered diamond, which results in a gain in shaping time (sharping) and rapid boring by electro-erosion through the carbide alone.
EXAMPLE 5
A composite product formed of a CBN compact on a carbide support intended to form a double face cutting tool (FIG. 5) was formed by a method similar to that of Example 1.
As shown in FIG. 5, two layers 22 and 30 of powder containing ultra-hard product are placed in the molybdenum cup 20, on each side of the sintered tungsten carbide disk 24 containing cobalt as a binder, chamfered on both sides. Between disk 24 and the layers are placed two tungsten foils 32, covered with a thin carbon coating on the faces in contact with the disk. Layers 22 and 30 are formed of a mixture of CBN powder having a grain size of 1 to 30 μm, containing 10% by volume of a binder consisting of aluminium, silicon and carbon. Sintering is carried out at 55 kbar and 1450° C. for 5 mn.
The advantage of this type of tool, which can also be made with diamond, is that it has two cutting faces, allows boring by electro-erosion (EDM) and gains time in sharpening and grinding because of the reduction of the amount of CBN.
Numerous embodiments are further possible, using solutions making it possible to obtain thermostable products. It should in particular be noted that the catalyst binder of the ultra-hard product may be either mixed with the particles of the product, or deposited previously in the support. In the case of crystalline diamond on a WC support, the binder may be infiltrated from the support. It is also possible to adopt a cross-section of the compact which is not exactly in the form of a triangle but is approximately so.
In general, the angle of the chamfer (and so of the cross-section of the compact) will be between 3° and 15° in the case of an insert, and from 8° to 25° in the case of a machining tool.
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A composite abrasive product comprises a refractory carbide support and a ring-shaped compact having a rotational symmetry about an axis of the support. The compact has an axial thickness which is small as compared with the axial thickness of the support and a substantially triangular axial cross-section, said compact having a face metallurgically bonded to a chamfered circumferential part of the support and the two remaining faces joining at a cutting edge. A method for manufacturing such a product is also disclosed.
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CROSS REFERENCE TO RELATED APPLICATION
This application claims priority to U.S. provisional application entitled, “Seafood Preservation Process,” having Ser. No. 60/241,920, filed Oct. 20, 2000 now abandoned, which is entirely incorporated herein by reference.
TECHNICAL FIELD
The present invention is generally related to the preservation of seafood and other food products for consumer consumption, and more particularly is related to a process for preserving fish by treating fish with smoke and ozone to retard degradation of the fish and maintain the fresh-like appearance of the fish. Optionally, the fish can then be frozen to further prolong its shelf life
BACKGROUND OF THE INVENTION
The preservation of fish has been a major concern for fishermen and fish processors for centuries. Originally man salted and dried fish to preserve it. Since the advent of mechanical refrigeration, the fish have been preserved by freezing and refrigeration, thus permitting fishermen to make longer fishing trips, as well as transport the fish long distances over land or water.
The length of time over which fish maintains its freshness is commonly referred to as its shelf life. The shelf life of fish is determined by a number of factors, including the total number of each type of bacteria initially present, the specific types of bacteria present, the temperature of the flesh of the fish and of the surrounding atmosphere, and the pH of the fish. It is known that to extend the shelf life of fish, one may, for example, reduce the number of bacteria present using chemical means, freezing or other methods, create an acidic pH and/or maintain the product below 5° C. in its fresh state. The most common process employed to extend the shelf life of fish is freezing.
An inherent problem with freezing fish is its loss of the “fresh” attributes such as a “pink” or “red” meat color to both the fish flesh and the “blood line” in the fish. The loss of these attributes causes the value of the frozen fish to be much less than the value of fish that has not been previously frozen. This loss of value is an interpretation of the quality of the fish by the consumer. The color of the flesh and blood line of the fish is a major factor in the selling of seafood at the consumer level. Most consumers purchase fish with their “eyes” rather than with any other factor, such as smell, taste or texture. Therefore, it is desirable to maintain the “fresh” pink/red color of the seafood products as long as possible in order to sell the product at a premium to consumers.
Although many factors may effect changes to the color of fish products, the main reduction of color results from damage to the hemoglobin pigments in the fish. Several of the primary causes for the reduction of hemoglobin pigments, resulting in a corresponding reduction in the “fresh” color of the fish, include oxidation of the “red” hemoglobin pigments in the flesh to a “brown” color; bacterial decomposition of the cells containing the hemoglobin pigments; and destruction and oxidation of the hemoglobin pigment during freezing.
Most unfrozen fish is considered “fresh” for as many as 30 days from catching. However, unfrozen fish this old usually contains high levels of dangerous bacterial decomposition. Bacterial decomposition of fish is the cellular breakdown of the flesh of the fish due to the digestive enzymes of bacteria present on or within the flesh of the fish. Conversely, frozen fish is usually frozen upon catching which reduces the likelihood that the fish will contain significant or harmful levels of bacterial decomposition.
In order to preserve the freshness of the fish and maintain the color of the flesh and blood line to a satisfactory consumer level, processes using smoking and freezing techniques have been applied.
Smoking of fish has been one of the major forms of fish preservation for centuries. Smoking involves the burning of organic substances, such as wood, to produce a complex mix of over 400 separate chemical compounds. These compounds, when continually exposed to fish flesh, are absorbed into the meat over time and impart a smoke flavor to the flesh. The smoke compounds act as a natural “bacteriostat” and greatly increase the refrigerated shelf life of the flesh (up to three times the un-smoked shelf life). Smoking of fish increases the shelf life by killing a majority of the bacteria initially present, and then creating an acidic environment that slows the growth of bacteria over time in refrigerated conditions. The compounds in the smoke that are primarily responsible for the extension of the shelf life of fish are the aldehydes and phenols, as well as CO, CO 2 , NO, NO 2 , which are the main gaseous components of smoke. These compounds maintain the “fresh” color of the fish, as well as prevent the growth of bacteria both on the surface of the fish and within the flesh.
However, one of the problems inherent in smoking fish products to impart preservation properties is that the smoke odor and/or smoke taste remains present in the fish flesh. Additionally, smoke that is produced from organic fuel materials typically contains particulates, such as creosote, tar, soot, etc., which are undesirable elements to have in contact with the fish product. Thus, it is beneficial to provide a smoke that has had some of the particulate removed and further remove the smoke odor/taste while still maintaining the extended shelf life.
U.S. Pat. No. 5,972,401 to Kowalski discloses a process for manufacturing a tasteless, super-purified smoke for the treatment of seafood and meat. The super-purified smoke is then applied to seafood or meat to preserve the freshness, color, texture, and natural flavor, particularly after the seafood or meat is frozen and thawed. Kowalski teaches that the smoke must be super-purified by filtering out a substantial amount of odor and taste imparting particulate matter and gaseous vapors, thereby recovering the smoke in a tasteless form. Thus, Kowalski is limited in that it requires that the smoke be super-purified into a tasteless form in order to prevent the impartation of the smoke odor or taste to the seafood or meat products.
U.S. Pat. No. 5,484,619 to Yamaoka discloses a process for smoking fish and meat at low temperatures, thereby conferring a smoked flavor and taste, and further preventing decomposition and discoloration of the fish or meat. As in Kowalski, the smoke is filtered to remove the larger particulates and provide a smoke that will preserve, sterilize and aid in maintaining the color of the flesh of the fish or meat. However, Yamaoka teaches that the smoke odor or taste will remain in the fish or meat and that the temperature of application of the smoke is important. Specifically, the Yamaoka smoke preservation process must be carried out at extremely low temperatures (between 0 and 5° C.) in order to maintain the freshness and quality of the fish or meat products Therefore, Yamaoka is limited to a smoke process for preserving fish or meat products wherein the product will retain a smoke odor or taste, and the process is further limited to a narrow range of temperature conditions.
U.S. Pat. No. 2,120,237 to Brenner et al. discloses a method for partially drying and then smoking fish fillets to preserve them. The fish fillets were first dried to remove a substantial portion of the moisture present and then treated within a smoke atmosphere. This method imparted a smoke flavor to the dried fillets and aided in the prevention of the fish deterioration.
It is also known to preserve the freshness or color of fish or other meat products by several other methods of treatment. U.S. Pat. No. 3,859,450 to Alsina teaches that melanosis (blackening) in shellfish is prevented by application of an innocuous acid solution followed by carbon dioxide gas. The resultant chemical reaction between the acid solution and the carbon dioxide produces carbonic anhydride that penetrates the shellfish and prevents melanosis during preservation by freezing. The process also discloses that the use of a food preservative, such as metabisulphite, will prolong the preservation of the original taste and texture of the shellfish after thawing.
U.S. Pat. No. 4,522,835 to Woodruff et al. discloses a process for maintaining good color in meat, poultry and fish products. Specifically, Woodruff teaches that subjecting the product to an atmosphere containing a low oxygen concentration and followed by an atmosphere containing a small amount of carbon monoxide will convert oxymyoglobin to carboxymyoglobin. The process produces a red color in the product and permits lengthy refrigeration of the product (two to three weeks). Further preservation is accomplished by Woodruff by maintaining the product in a modified carbon dioxide atmosphere or by freezing.
U.S. Pat. No. 5,540,942 to Tokoro teaches that the freshness of meat or fish may be improved by treatment with ubidecarenone to prevent discoloration of the product. The ubidecarenone additive prevents the oxidation of the haem pigments, thereby maintaining the red color of “fresh” product by preventing discoloration to a brown or gray appearance.
Ozone, a GRAS (generally regarded as safe) substance, has been used for more than ten years to sanitize, deodorize and prevent bacterial growth in food items. Its main strength is in the killing of surface and subsurface bacteria that lead to decomposition of fish flesh during refrigerated storage. Ozone may be applied using a gaseous or liquid medium or a combination thereof.
U.S. Pat. No. 5,783,242 to Teague discloses a process of treating poultry with ozone and ozone dissolved in water to reduce the population of contaminating organisms. The product is first subjected to a solution containing ozone and then exposed to a gaseous atmosphere containing ozone. The product is also subjected intermittently to UV exposure which further acts as a bactericide and decomposes any ozone remaining on the product into oxygen.
Although, it is known that the foregoing techniques may be used to preserve the fish flesh itself, these techniques often result in an appearance of fish that has lost its “fresh” attributes. Accordingly, without the ‘pink’ or ‘red’ color of the fish flesh, consumers often consider such preserved fish as “not fresh,” resulting in a lower sales price for the fish. The foregoing techniques claim to maintain the color of the fish do so with the addition of chemical additives and preservatives which can alter the taste and texture of the fish or be toxic in certain dosages to humans. Additionally, maintaining the “fresh” attributes of the fish is not taught when the fish is preserved or further preserved by freezing.
Therefore, a heretofore unaddressed need exists in the industry to satisfy the aforementioned deficiencies and inadequacies and provide a preserved fish that retains all of the qualities and characteristics of a “day caught” fish.
SUMMARY OF THE INVENTION
Through research and product development, the inventors have devised a process for fish preservation that results in the production of an extremely high quality, fresh seafood product line with extended shelf life characteristics. The fish products are preserved using smoke and ozone so as to maintain the qualities and characteristics of freshly caught fish.
The process allows the transportation of fresh and frozen seafood items from remote areas of the world in a safe, sanitary and economical way. However, Applicants' preservation process has overcome the drawbacks of typical freezing techniques and allows the consumer to receive a high quality, extremely safe fish with the taste, texture and attributes of freshly caught fish. The fish appears “fresh” to consumers as it retains its red, or bright, color and is, thus, more appealing.
In general, the process includes the steps of smoking of fresh fish, treating it with ozone and optionally freezing the fish. When a smoke and ozone process is utilized, the shelf life is extended and the fish retains more of its “fresh” color. The smoke/ozone process retains the “fresh” color and extends shelf life of the fish flesh by binding the carbon monoxide molecule to the heam pigment in the hemoglobin molecule in such a way that it takes much greater than normal oxidative force to oxidize the hemoglobin molecule. Furthermore, the smoke/ozone process aids in the prevention of bacterial decomposition and maintains the hemoglobin molecule (red color) during freezing and frozen storage by binding it with a CO molecule.
Optionally, the smoke/ozone process can include the steps of wiping the flesh of the fish with alcohol one to three times during the preservation process, before or after smoking the fish. The application of alcohol to the exterior of the fish kills surface and shallow bacteria on contact with the alcohol. The fish would be placed in a modified “smoke” atmosphere for 1 to 72 hours, with the length of time depending on the thickness of the fish product, with thicker products requiring more time than thinner products. If the smoke is applied to the fish while in a vacuum chamber, the time required for the smoke application can be reduced to less than a minute. During the smoking step, a vast majority of “aerobic” bacteria die as there is no oxygen available for them to breathe. The smoking step additionally creates an acidic pH in the fish by the dissolution of free carbon dioxide, present in the smoke, into the fish. The acidic pH prevents the growth of bacteria during the “fresh” stages of the process. An optional final step can involve freezing the product to kill an additional percentage of the bacteria present on the product The fish product can be initially prepared into appropriately sized sections or fillets in order to accelerate the smoke/ozone application steps.
With the use of this fish preservation process, the shelf life of the product is increased, usually from about 2-3 days after the product is landed to about 10-12 days. This increase in shelf life after the product has been treated allows the product to be shipped to remote areas requiring longer shipping times. Also, the final processing of the product into consumer-ready forms, including cutting, portioning and packing the product, can be performed at the central processing facility. This avoids the necessity of having to perform the final processing of the product at the store level.
Other processes, systems, methods, features and advantages of the present invention will be or will become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional processes, systems, methods, features and advantages be included within this description, be within the scope of the present invention, and be protected by the accompanying claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
FIG. 1 is a cross sectional view of an open top liquid container with a basket of fish products immersed in a brine.
FIGS. 2-4 are schematic elevational views of a vacuum bag and the fish products contained therein, showing the bag in its relaxed, vacuum and inflated configurations, respectively.
FIG. 5 is a schematic view of the smoke machine.
FIG. 6 is a side elevational view of the centrifuge used in the smoke machine.
FIG. 7 is a cross section of the centrifuge, taken along lines 7 — 7 of FIG. 6 .
FIG. 8 is a side view of the bag filling device
FIG. 9 is a perspective view of the ozone dipping tank and basket.
FIG. 10 is a plan view of the ozone chamber used for fish steaks.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The inventors have devised a process for preserving seafood products and other meat products of various types. Typically, the first step of the process involves the initial preparation of the fish product into appropriately sized sections 101 . The skin and bones may either be removed or may be left on. As shown in FIG. 6, if the fish is of the pelagic species, such as salmon or tuna, the fish can be cut into loin portions or steaks 102 . If any loin portion has a thickness that is too big for expedient smoke and/or ozone treatment, the loins can be cut into steaks.
As shown in FIG. 1, the sized fish product 101 is placed in a single layer in a basket 105 or porous tray, preferably plastic, and the basket with the fish is immersed into an aqueous solution 104 of salt and baking soda in a container 103 . The container 103 for the aqueous solution should have sufficient dimensions such that the fish products 101 are maintained in a single layer and are completely immersed in the aqueous solution 104 . The aqueous solution 104 preferably is a thoroughly mixed solution in a ratio of approximately ten liters of cold water at approximately 2 to 5° C., 200 grams of salt and 100 grams of baking soda.
The fish product 101 in the basket 105 is completely immersed in the aqueous solution 104 for approximately twenty seconds, after which time it is removed with the basket from the container 103 and the excess aqueous solution 104 is allowed to drain away from the fish. The fish product 101 usually is then patted dry using a porous plastic sponge, or the like, (not shown in the drawings) that has been previously sanitized in alcohol.
As shown in FIG. 2, the dry fish products 101 are then inserted into a vacuum bag 106 or another type of container in a single layer of the products. It is acceptable for the products to come in contact with each other. As shown in FIG. 3, the vacuum bag 106 or other type of vacuum container is vacuum sealed about the products using a conventional vacuum packaging machine (not shown). The vacuum seal formed about the products should be tight enough to remove substantially all of the air from the container 106 , but not so tight as to damage or flatten the fish product.
Once the air has been removed from the sealed container 106 , the container is filled with filtered smoke 107 as shown in FIG. 4 . The container 103 should be filled with smoke until there is a slight pressure on the container. The container should remain sealed, such as with heat sealing of the layers of a plastic bag together, to prevent any of the smoke from exiting the bag 106 .
The smoke can be generated by a smoke machine 110 , as shown in FIG. 5 . The smoke machine 110 includes a smoke generator 111 , a smoke cooler 112 , a centrifugal precipitator or centrifuge 114 , motor 115 , a centrifuge fan 116 and connecting belt and sheaves 118 . Motor 115 rotates centrifuge fan through the belt and sheaves in a conventional arrangement. Dirty smoke draw chamber 120 and its suction fan 121 draw the dense or dirty smoke from the centrifuge through mid height exhaust conduit 122 , and push the smoke through a filter 124 to the atmosphere. Some of the heavier precipitates of the smoke will move down the converging interior wall 125 of the centrifuge housing 126 through the open bottom to a water trap 128 .
The clean smoke is gathered at the vertical axis of the converging conical interior wall of the centrifuge by the inlet opening 129 of the clean smoke exhaust conduit 130 . The clean smoke exhaust conduit leads to clean smoke exhaust compressor 131 , through filters 132 to smoke storage tank 134 .
It would be apparent to one skilled in the art to modify the aforementioned embodiment of the smoke machine 110 by the addition or deletion of certain devices without substantially altering the purpose of supplying a filtered smoke. The smoke generator 111 is of conventional construction and is adapted for the burning of wood or other organic material for the generation of smoke. The smoke is passed from the smoke generator 111 through the smoke cooling conduits 113 of the smoke cooler 112 . Cold water is circulated about the smoke cooling conduits to chill the smoke from about 900 degrees F. as it exits the smoke machine to about 400 degrees F. before moving into the centrifuge.
After the smoke has been generated by the smoke generator 111 and passed through the smoke cooler 112 , it is passed through the centrifuge 114 . The centrifuge 114 removes the majority of the particulate phase, i.e. any particle larger than approximately one micron, of the smoke. The particulate phase, which contains mainly ash and tar, is removed by running the product through the centrifuge 114 (see FIGS. 5 and 6 showing typical centrifuge design and implementation). The centrifuge 114 creates a cyclone effect inside the main chamber 117 by spinning a “squirrel cage” fan blade 116 at a speed of approximately between 3600 and 4000 rpm. The spinning action causes the heavy particulates of the smoke, mainly tar, to be flung by centrifugal force against the inside surface of the perimeter wall 125 of the chamber 126 at high velocity. The heavy particulates then move down the inside wall and funnel down to a collecting receptacle or water trap 128 at the bottom of the conical chamber 126 . The collecting receptacle 128 is partially filled with water at the lower open end of the centrifuge 114 so as to trap the heavy smoke particulates being exhausted by the precipitator. With the heavy particulate phase removed, the lighter, cleaner smoke at the center of the vertical axis 119 of the centrifuge 114 enters the outflow pipe and is directed into the smoke storage tank 134 .
Excess uncleaned smoke is directed through mid height exhaust conduit 122 and through exhaust suction fan 121 . Fan 121 is a variable speed fan that regulates the amount of smoke drawn through the system.
The clean smoke is dispensed on demand from the centrifuge 114 by the compressor 131 . The resulting clean smoke exits the centrifuge 114 with a very clear appearance. It is directed by the compressor 131 and its connection hoses through a final filtering device 132 and is collected and maintained in a smoke storage tank 134 . When a smoke storage tank is filled with smoke it is refrigerated and stored for later use.
As illustrated in FIG. 8, the cooled cleaned smoke is later inserted into the vacuum bag 106 with the fish product 101 by placing the hollow needle 140 of an air chuck 141 , which is connected to the smoke storage tank 134 via clean smoke dispensing conduit 142 , into the bag 106 and pulling the trigger mechanism 144 . This opens a valve and allows the clean smoke to move into the vacuum bag 106 . For high volume production, the bag 106 can be filled by using a modified atmosphere packaging system like the CVP AT600. If another type of vacuum chamber is used, not a bag, the smoke can be dispensed into the chamber by using a valve controlled conduit.
The filtered smoke will have an initial level of CO/CO 2 in the vacuum chamber and the CO/CO 2 level should be periodically measured. When the CO/CO 2 level begins to decline appreciably, the vacuum chamber is voided of and refilled with smoke until the color characteristics of the fish have stabilized. This procedure should preferably occur at a temperature range of 0 degrees C. to 5 degrees C. and can take anywhere from 1 minute to 72 hours depending on the type of fish product and the characteristics of the smoke and the method of applying the smoke. After this, the smoked fish product is placed in an ozonated environment at a temperature range of about 0 degrees C. to 5 degrees C. and is maintained in the ozonated environment until the odor of smoke is no longer detectable. Depending on the type of fish product and the amount of smoke odor that the product has absorbed during the smoking step, it may take anywhere from 1 minute to 72 hours depending on the type of fish product, the characteristics of the smoke, and the method of applying smoke, for the smoke odor to be sufficiently diminished that it is no longer detectable. The fish product is then removed, vacuum sealed and can be optionally frozen using conventional freezing techniques. When it is desired to use or display the fish product, the fish product is defrosted. The present process for preserving the fish product results in a refreshed fish product that closely parallels a day caught fish in quality, characteristics and appearance.
When the decline of the CO/CO 2 level slows appreciably during the smoke application process, the remaining smoke should be removed from the vacuum chamber 106 and replaced with another charge of smoke, as might be necessary. The smoking step should be repeated until the color characteristics of the fish product 101 have stabilized. Depending on the type of fish product 101 , the temperature and the smoke characteristics, it may take between approximately twelve to seventy-two hours at atmospheric pressure to satisfactorily complete the smoking step. However, if the smoke is applied in a vacuum chamber at a reduced pressure to the product, the smoke application step can be performed in minutes.
Once the smoking step is complete, the fish product 101 is removed from the vacuum chamber 106 and may be patted dry using a porous plastic sponge, or the like, sanitized with alcohol. The product is checked for smoke odor. As shown in FIG. 9, the fish product 101 is then placed in a basket 150 or other porous tray device. The fish product 101 may be situated within the basket 150 in either a single or double layer configuration. The basket 150 is then immersed into an ozone dipping tank 151 , that contains chilled (at about 5° C.) ozonated water 152 (approximately 2 ppm ozone) for between approximately one minute and one hour. The product can be left in the ozonated water for more than one hour, if desired.
The odor of the fish product 101 is periodically monitored by removing the basket 150 from the ozonated water 152 and sniffing to detect a smoke odor. At the point that the smoke odor is no longer noted, the fish product 101 should be removed from the ozonated water 152 and any excess ozonated water 152 should be allowed to drain away from the basket 150 .
The fish product 101 is then placed in a vacuum bag and vacuum sealed. The fish product 101 can be left unfrozen or can be frozen for even longer shelf life, using conventional freezing techniques. If frozen, the fish product 101 should be stored and maintained at temperatures below −18° C.
When the use of the frozen fish product 101 is desired, the product is defrosted while in the bag by either placing the bag in a cooler between 2 and 5° C. or by placing the bag in a basin of cold water. The refreshed fish product 101 will substantially retain the quality and characteristics of a freshly caught fish and may then be displayed or maintained at refrigerated temperatures for up to six more days.
If the fish product 101 is tuna, or other pelagic species, the ozone step is applied using a different technique. As shown in FIG. 10, instead of using the ozone dipping tank 151 , pelagic fish steaks 102 can be ozonated in an ozone chamber 160 for better results. FIG. 6 illustrates an ozone chamber 160 design comprising an ozone generator 161 , intake 162 , deflector 164 , chamber 165 , exhaust 166 and product holding rack 168 . After the fish steaks 102 have been smoked and optionally wiped with an alcohol soaked sponge, the fish steaks 102 are placed on racks 168 in the ozone chamber 165 . The fish steaks 102 should remain in the ozone chamber 165 for approximately one minute to four hours or until they reach the desired level of smoke odor. Once the fish steaks 102 have been ozonated, they can be placed in a vacuum bag and vacuum sealed. For freezing they are placed in a vacuum bag and are vacuum sealed. For fresh fish, the fish are placed in distribution-ready packages.
As with the fish product 101 , when the frozen fish steaks 102 are to be used, the bag is defrosted by either placing the bag in a cooler between 2 and 5° C. or by placing the bag in a basin of cold water. The refreshed fish steaks 102 will retain qualities and characteristics of a fresh caught fish and may then be displayed or maintained at refrigerated temperatures for up to six more days.
Although the aforementioned embodiments are directed to fish products, it is anticipated by the inventors that the claimed preservation process may be applied with equally satisfactory results for fish, beef, pork, poultry and crustaceans. Additionally, the methods for applying the smoke and ozone, and for freezing may be varied from those specifically disclosed herein.
Particularly, it is anticipated by the inventors that the smoke may be applied under atmospheric, vacuum or pressured conditions and in any suitable containment vehicle, including heated or refrigerated conditions. The smoke itself may be comprised of any smoke suitable for treatment of food products for human consumption; may be generated by any number of means including, but not limited to, combustion, transformation between solid or liquid state to gaseous state, friction, pyrolysis, aerobically, anarobically, electrical heating or direct flame; and may be used in its whole or filtered state. If the smoke is filtered to remove any component of the smoke, such filtering may be performed by any physical means, carbon filtering, ice column filtering, centrifugal force, electrostatic force, or other known means of separating out a component of smoke. The smoke may be applied to the products in an open, batch, closed or flow-through system.
Likewise, the ozone treatments disclosed above in the preferred embodiments are not exclusive. The inventors anticipate that the ozone may be applied using any type of carrier medium including, but not limited to, air, gases, water, fluids or solids and under atmospheric, vacuum or pressured environments and in any suitable containment vehicle, including heated or refrigerated conditions. The ozone that is applied is not limited to “pure” ozone, but may be in reaction form, mixtures, solutions or other form. The ozone may be applied to the products in an open, batch, closed or flow-through system.
The freezing step of the preservation process may be accomplished using any number of conventional freezing applications. Particularly, it is anticipated by the Applicants that suitable freezing can occur under atmospheric, vacuum and pressured conditions in gaseous, liquid or solid freezing mediums or combinations thereof.
While the process described herein involves the treatment of fresh fish, a similar process can be applied to frozen fish. One such process is to thaw the frozen fish and later apply the smoke and ozone to the fish. A preferred process of treating frozen fish is to simultaneously thaw and smoke the fish in a chamber. This can be done in a vacuum chamber. This eliminates the exposure of the fish to standard atmosphere as it thaws.
It should be emphasized that the above-described embodiments of the present invention, particularly, any “preferred” embodiments, are merely possible examples of implementations, merely set forth for a clear understanding of the principles of the invention. Variations and modifications may be made to the above-described embodiments of the invention without departing from the spirit and principles of the invention. All such modifications and variations are intended to be included herein within the scope of this disclosure and the present invention and protected by the following claims.
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The preservation of meat products is accomplished utilizing a combination of smoke, ozone and freezing preservation techniques. Particularly, fish products are sized into portions that are first treated with smoke, followed by treatment with ozone and then optionally frozen. The preservation system extends the shelf life of the fish products and permits the fish to maintain its freshness and freedom from bacterial decomposition for a longer period of time following catch. The preservation process further maintains the characteristics of day caught fish, such as taste, texture and color, making the refreshed fish products produced by the present system more appealing to consumers.
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[0001] This application is a divisional of patent application Ser. No. 10/119,221, filed Apr. 9, 2002 which is a continuation in part of Provisional Application Ser. No. 60/282,577
TECHNICAL FIELD
[0002] The present invention relates generally to vehicle roller shade assemblies, and more particularly to such an assembly having a locking end cap.
BACKGROUND OF THE INVENTION
[0003] Rollers for security shades for covering rear compartments of SUV's or hatchback vehicles, or for shades for covering automobile windows, or rollers for barrier nets, have long been used in the art. While these rollers are valuable accessories to most consumers, it is often desirable to remove the roller from the vehicle, thus making ease of installation and removal from the vehicle a key feature of the device.
[0004] Another key criteria with respect to such rollers is their ability to accommodate variations in the build of multiple numbers of a single model vehicle. For example, security shades are typically mounted into brackets between the interior trim panels inside the vehicle. If the distance between the two trim panels varies between cars of the same production by tenths of inches, the roller must still be able to fit between the panels and not rattle back and forth.
[0005] A preferred approach to holding the roller in place is to utilize end caps at the ends of the rollers, one or both of which are spring loaded. To install the rollers, the end caps are compressed to fit the roller into the brackets, and, when released, the spring or springs in the end caps exert an axially outward force against the brackets on the trim panels, keeping the roller in place. See for example, U.S. Pat. No. 5,464,052, issued to the assignee of this application. This spring loaded design also provides a self-centering action, while allowing for easy installation or removal, even with one hand.
[0006] There have been various attempts to even further secure the roller within the brackets, which have met with relative amounts of success. These devices typically add weight and/or cost to the shade, or limit the advantages of the floating endcaps, or make the shade significantly more difficult to install or remove. For example, one device requires pushing a button to release a lock, which mandates the use of two hands for removal. Another device utilizes a “click-pen” type of locking mechanism, which is also somewhat cumbersome and which detracts from the stabilizing effects of the spring loaded endcaps.
SUMMARY OF THE INVENTION
[0007] In one aspect, the present invention provides an endcap for a vehicle shade roller assembly. The end cap includes a cap body having an exterior surface and an end face substantially perpendicular to the exterior surface. A knob extends from the end face and has a shaft portion and at least one flange extending in a substantially perpendicular direction from the shaft portion. The cap body is engageable with a bracket in a vehicle interior, the bracket having a slot substantially complementary with the at least one flange, and matable therewith by twisting the cap body relative to the bracket, thereby locking the cap body and its associated shade assembly.
[0008] In another aspect, the present invention provides a locking assembly for a vehicle roller shade. The locking assembly includes a cap body having a continuous exterior lateral surface and an end surface. a locking member protrudes from the end surface, and has a shaft and at least one flange disposed proximate an end of the shaft. The flange extends from the shaft in a direction substantially parallel to the end surface. A bracket is provided, and is attached to a vehicle trim panel, the bracket being adapted to receive the locking member and including a slot that engages the at least one flange in a complementary fashion. The flange is engageable with the slot by axially rotating the cap member relative to the bracket.
[0009] In yet another aspect, a vehicle roller shade assembly is provided. The roller shade assembly includes a windable shade roller member having an attached flexible shade panel. At least one end cap is provided, and is attached to the roller member. The end cap includes a cap body with a locking knob member extending in an axial direction from an end face, and having at least one flange. The end cap is reciprocable in an axial direction relative to the roller member. A bracket is also provided having a region substantially complementary to the at least one flange. The flange is engageable with the region by inserting the locking knob member into an aperture in the bracket and axially rotating the cap body relative to the bracket.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is an assembly drawing of endcaps for a shade roller assembly (not shown) in combination with brackets for mounting the roller assembly into a motor vehicle.
[0011] FIG. 2 is a detail drawing of an endcap according to a preferred embodiment of the present invention.
[0012] FIG. 3 is a perspective view of an endcap according to a preferred embodiment of the present invention.
[0013] FIG. 4 is a perspective view of an endcap mounted into a bracket according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0014] Referring to FIG. 3 , there is shown a perspective view of an end cap 10 according to a preferred embodiment of the present invention. End cap 10 has a slotted face 12 , an end face 11 , and a locking knob 14 protruding from end face 11 . End cap 1 is preferably a hollow plastic body formed by injection molding or some other suitable process, although it should be appreciated that it might instead be formed or stamped metal. In a preferred embodiment, end cap 10 is mounted at one or both ends of a conventional roller shade apparatus (not shown) for use in a vehicle storage compartment. End cap 10 preferably positions and secures the roller shade apparatus for deployment of a flexible shade panel over the vehicle cargo area. The slot 13 in slotted face 12 receives an edge of the flexible shade panel so that the winding and unwinding shade panel can pass therethrough, and allows end cap 10 to be axially compressed without disturbing the shade panel. In a preferred embodiment, end cap 10 is fixed to the roller shade apparatus, yet reciprocable between a retracted and an extended position, being biased by a biasing member (not shown) toward its extended position. It should be appreciated, however, that the biasing member is not critical, and embodiments are contemplated in which end cap 10 is not biased.
[0015] At the axial outer face of the end cap 10 is the protruding locking knob 14 . Locking knob 14 preferably includes a pair of locking flanges 16 that extend outwardly from a shaft 17 of the knob. In a preferred embodiment, the flanges 16 are substantially flat and extend parallel to end face 11 , and are positioned on opposite sides of shaft 17 . Thus, knob 14 is preferably symmetrical in an end view. Alternative embodiments are contemplated, however, in which knob 14 has flanges positioned at a right angle, and even a version having only a single flange. Referring now in addition to FIG. 4 , installation of end cap 10 (and its associated shade roller assembly) begins by securing a first end of the shade roller to a vehicle interior trim panel 18 , then compressing the opposite end cap 10 toward the first end. Axial compression of end cap 10 preferably retracts knob 14 to provide the clearance necessary to position the locking knob 14 in a bracket on an opposite trim panel. In a preferred embodiment, an end cap 10 is mounted to each end of the roller shade assembly; however, a single end cap may be used if desired. Where only a single end cap 10 according to the present invention is used, the end of the roller shade assembly without the end cap may be secured to the trim panel by other means, for example with a hook. When the compressed end cap 10 is released, the biasing members (preferably at both ends) urge the end caps outward, extending knob 14 into a substantially complementary aperture in the trim panel. In addition, the outward bias on the end caps centers the roller assembly in the cargo compartment and prevents its shifting or rattling during vehicle operation. Because the end caps are preferably spring loaded, they can move axially automatically to accommodate variations in internal widths among different individual vehicles. In an embodiment without biased end caps, the end caps may be moved manually to fit a particular vehicle interior width.
[0016] Once the roller is positioned accordingly, i.e. with knob 14 positioned in the aperture in the mounting bracket, the assembly can be rotated to bring the flanges of the locking knob(s) into engagement with substantially mating vertical slots disposed internally in the trim panels (not shown). The engagement of the flanges with the mating slots locks the assembly in place, and prevents dislodging during shade deployment or vehicle operation. In a preferred embodiment, the slots for receipt of the flanges should be dimensioned to receive the flanges with a relatively snug fit, though not so tight as to make engagement and disengagement difficult. The slots might also be configured to have a tapered internal diameter, allowing the flanges to be brought into gradually tightening engagement therein. Although a preferred embodiment contemplates two flanges symmetrically positioned on opposite sides of the knob 14 , alternative constructions are contemplated. For instance, rather than employing opposing flanges, a single flange might be used. In this embodiment, a trim panel aperture for receiving knob 14 can be shaped such that it can insertably receive the knob only when the knob and flange are oriented in a particular way. Similarly, flanges positioned on the shaft 17 at right angles to one another could only be inserted into the trim panel aperture if appropriately oriented with respect to the aperture. Stated another way, the trim panel aperture may be fashioned substantially complementary to the flanges. The end cap must be axially rotated to the proper position before initial insertion into the aperture. It should be appreciated that separate bracket members may be mounted to the vehicle trim panels; alternatively, the brackets for receipt of the locking knobs may be formed integrally with the trim panel to enhance the appearance of the vehicle when the roller is not installed. Yet another embodiment is contemplated in which the brackets themselves may be rotated to engage the flanges with their respective slots.
[0017] Thus, in the preferred embodiment shown in FIG. 3 , the roller shade assembly having end cap 10 is initially positioned in a vehicle with its slot 13 facing an upward direction, and its flanges 16 extending in a horizontal direction relative to the vehicle trim panel. Once the end caps are axially compressed, and inserted into the trim panel, the entire assembly is preferably rotated approximately ¼ turn, securing the assembly in place, and rotating slot 13 to face a substantially rearward direction in the vehicle. Thenceforth, the shade can be pulled and retracted from the assembly in a conventional manner. Alternatively, installation might proceed by initially positioning the assembly with slot 13 facing a downward direction, then rotating the assembly to bring the slot upward to face a rearward direction in the vehicle. In either of these techniques, an approximately 180° rotation would bring the slots back into alignment with the insertion aperture, and allow disengagement of the knob. Stated another way, there are two possible axial positions of the knob, separated by 180°, at which it may be inserted or removed from the mounting bracket. So long as the flanges are not aligned with the insertion slot, the assembly is secured. Because this configuration allows removal at two separate positions, it is preferred in applications where the roller shade will be frequently installed and removed. In the aforementioned embodiments in which only one insertion orientation of the knob is possible, less flexibility exists in the possible orientation of the knob for installation and removal. Once installed, however, the assembly (and thus the end cap and knob) may be axially rotated with less risk of bringing the knob back into a position at which it can dislodge from the aperture. Similarly, in this embodiment, during normal vehicle operation there is a lesser chance that the shade assembly will inadvertently rotation to an orientation where it will dislodge.
[0018] The present invention represents a relatively simple design for rapid installation and removal of a conventional roller shade assembly from a vehicle. Additionally, the use of axially movable end caps facilitates application of the assembly to vehicle models having non-uniform interior dimensions. The present description is intended for illustrative purposes only, and should not be construed to limit the breadth of the present invention in any way. Thus, those skilled in the art will appreciate that various modifications might be made to the presently disclosed embodiments without departing from the spirit and scope of the present invention. Other aspects, features, and advantages will be apparent upon an examination of the attached drawing figures and appended claims.
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An endcap for a vehicle shade roller assembly is provided. The end cap includes a cap body having an end face, the cap body being axially reciprocable among a plurality of positions relative to a shade spindle. A knob is fixed to the endcap and protrudes from the end face, and has at least one flange extending substantially parallel to the cap body end face. The knob is extendible into a vehicle trim panel, thereby positioning the at least one flange adjacent a substantially complementary structure in the trim panel such that an axial rotation of the end cap engages the flange with the substantially complementary structure to secure the endcap and its associated roller shade assembly.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of Ser. No. 12/487,179, filed on Jun. 18, 2009, which claimed the benefit under 35 U.S.C. 1.19(e) of U.S. provisional No. 61/132,651 filed Jun. 20, 2008, the contents of which are hereby incorporated by reference herein in their entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to compositions for the control of adrenocortical disease in ferrets.
2. Description of the Prior Art
Adrenocortical disease (ACD) in ferrets ( Mustela putorius furo) is a common problem in neutered, middle-aged to old ferrets. The adrenal tissues of these ferrets develop nodular hyperplasia, adenomas, or adenocarcinomas which occasionally results in death. The adrenal tissues of these ferrets also exhibit an increase in the production of a variety of steroid hormones, including estradiol, 17-hydroxyprogesterone, and androstenedione, to pathological levels. The major clinical signs attributable to these hormones are alopecia in both sexes and a swollen vulva in females. Pruritus, muscle atrophy, hind limb weakness, and sexual activity or aggression are observed less frequently. Males can develop prostatic cysts, prostatitis, and urethral obstruction. As the disease progresses, there is often a decrease in the apparent quality of life. Occasionally, adrenal gland tumors continue to grow, invade tissues locally, and become necrotic; rarely, they rupture causing death. Additional potentially fatal sequelae include metastases and bone marrow suppression associated with chronic exposure to high serum estrogen concentrations [Rosenthal & Peterson. Evaluation of plasma androgens and estradiol concentrations in ferrets with hyperadrenocorticism. J Am Vet Med Assoc. 1996. 209:1097-1102; Wagner & Dorn. Evaluation of serum estradiol concentrations in alopecic ferrets with adrenal gland tumors. J Am Vet Med Assoc. 1994. 205:703-707; Rosenthal et al. Hyperadrenocorticism associated with adrenocortical tumor or nodular hyperplasia of the adrenal gland in ferrets: 50 cases (1987-1991). J Am Vet Med Assoc. 1993. 203:271-275; and Weiss & Scott. Clinical aspects and surgical treatment of hyperadrenocorticism in the domestic ferret: 94 cases (1994-1996). J Am Anim Hosp Assoc. 1997. 33:487-493].
ACD is thought to be due to an increase LH concentration, often present in neutered ferrets, with acts on the luteinizing hormone (LH) receptors on the adrenocortex resulting in adrenal gland hyperplasia, tumor induction and growth, and increased steroid hormone secretion. There is speculation that the high prevalence of ACD in pet ferrets is associated with neutering at an early age, and may be a result of chronic stimulation of the adrenal gland cortex by pituitary gland gonadotropins (i.e., follicle stimulating hormone [FSH] and LH) (Rosenthal & Peterson. ibid; Shoemaker et al. Correlation between age at neutering and age at onset of hyperadrenocorticism in ferrets. J Am Vet Med Assoc. 2000. 216:195-197; and Shoemaker et al. The role of luteinizing hormone in the pathogenesis of hyperadrenocorticism in neutered ferrets. Mol and Cell Endocrinol. 2002. 197:117-125). Exposure to abnormally long photoperiods associated with indoor housing of pet ferrets is also thought to contribute to the pathogenesis of ACD. Long light cycles of >8 hours have been shown to stimulate production of gonadotropin-releasing hormone (GnRH) and LH and decrease serum melatonin concentrations, a known antigonadotropic hormone in ferrets [Jallageas et al. Differential photoperiodic control of seasonal variations in pulsatile luteinizing hormone release in long-day (ferret) and short-day (mink) mammals. J Bio Rhythms. 1994. 9(3-4):217-231].
Down regulation of GnRH receptors and subsequent suppression of the production and release of these gonadotropins have been shown to reduce specific hormone production and eliminate hormone effects in ferrets [Wagner et al. Leuprolide acetate treatment of adrenal cortocal disease in ferrets. J Am Vet Med Assoc 2001; 218 (8): 1272-1274; and Wagner et al. Clinical observations and endocrine response to treatment of adrenal cortical disease in ferrets with GnRH (deslorelin acetate) implants. Am J Vet Res 2005; 66 (5): 910-914]. In humans, GnRH analogs administered at pharmacologic doses downregulate GnRH receptors at the pituitary gland.
Gonadotropin-releasing hormone agonists are a relatively new class of drugs, which, when chronically administered, result in marked reductions in blood levels of testosterone and estrogen. These drugs include leuprolide acetate, nafarelin acetate, deslorelin and goserelin acetate. Approved indications for these drugs, depending on the specific agent, include advanced prostate cancer, endometriosis, and precocious puberty. At high doses, GnRH agonists causes downregulation of GnRH receptors at the pituitary gland, thereby inhibiting production and release of gonadotropins (LH and FSH). However, GnRH agonists have a relative short effectiveness and must be delivered in a slow release implant. This implant must be replaced every 12-13 months depending on the mg of drug in the implant.
SUMMARY OF THE INVENTION
We have now discovered that ACD in ferrets, and particularly domestic ferrets, Mustela putorius furo, may be prevented and/or treated by administration of gonadotropin releasing hormones (GnRH) or GnRH immunogenic analogs, each conjugated to a carrier protein. Administration of the GnRH or GnRH immunogenic analog significantly reduces the concentration of luteinizing hormone in the serum of a treated ferret, and significantly reduces the occurrence or clinical symptoms of ACD therein. Moreover, treatment of ferrets with the GnRH or GnRH immunogenic analog provides long term relief from ACD for a period of a year or more.
In accordance with this discovery, it is an object of this invention to provide an improved method for reducing the incidence and/or the severity of ACD in ferrets.
It is another object of the invention to provide a method for preventing or controlling ACD in ferrets by reducing the secretion of luteinizing hormone in neutered ferrets.
Yet another object of this invention to provide a method for reducing the incidence and/or the severity of ACD in ferrets for an extended period of time with only a single dose.
Other objects and advantages of this invention will become readily apparent from the ensuing description.
DETAILED DESCRIPTION OF THE INVENTION
It is believed that ACD in ferrets is caused by an increase in the secretion of LH, which acts on the luteinizing hormone (LH) receptors on the adrenocortex and results in adrenal hyperplasia, tumor growth, and increase in steroid hormones such as estradiol, 17-hydroxyprogesterone, androstenedione, and dehydroepiandrosterone. According to this invention, there is provided a method for decreasing the secretion of LH and thereby decreasing the incidence and/or severity of ACD in ferrets, including reducing the above-mentioned adrenal hyperplasia, tumor growth, and steroid hormone production. We have discovered that the administration to ferrets of GnRH or GnRH Immunogenic analogs which are conjugated to a carrier protein, leads to a suppression of the gonadotropins FSH and LH, and eliminates or significantly reduces the clinical signs of ACD. Without wishing to be bound by theory, it is believed that the administration of these immunogenic GnRH or GnRH analogs induces the body to produce antibodies against its own GnRH. These antibodies bind to endogenous GnRH, forming large immune-complexes that travel down the hypophysial stalk. Because of their large size, these immune-complexes are unable to diffuse out of the pituitary stalk capillaries into the pituitary, and without GnRH stimulation of the pituitary, release of LH and FSH is reduced or does not occur, and consequently the stimulation of the adrenal gland cortex and clinical ACD symptoms are also reduced. Moreover, in contrast with treatment with GnRH agonists which provide only temporary relief (3 to 6 months) of ACD, treatment with GnRH or GnRH analog vaccines in accordance with the instant invention provides significantly longer control of ACD, with a single dose administration providing effective reduction in LH serum concentrations and ACD symptoms for a period of a year or more.
GnRH (also known as Luteinizing Hormone Releasing Hormone, or “LHRH”) has long been recognized as being of central importance to the regulation of fertility in. animals. GnRH is a decapeptide which has the same amino acid sequence, i.e., pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-GlyNH 2 (SEQ. ID NO. 1) in all mammals. Throughout this description, the amino acid sequences conform with conventional practice with the amino terminal amino acid on the left and the carboxy terminal amino acid to the right. Owing to its small size, GnRH and its analogs are relatively poorly capable of stimulating the immune system to produce antibodies. To render these compounds immunogenic, they are generally conjugated to an immunogenic carrier in such manner that the resultant immunogen is capable of stimulating the immune system of the ferret to produce antibodies capable of binding to unconjugated GnRH.
While GnRH may be used in the immunogen preparation and is generally preferred, a variety of GnRH immunogenic analogs have also been described which are suitable for use herein. As noted hereinabove, GnRH is a small decapeptide. As defined herein, immunogenic analogs of GnRH include compounds containing a substitution, deletion, or insertion of between one and five amino acid residues in the above-mentioned GnRH amino acid sequence, as well as dimers or polymers thereof, which compound retains the ability to induce or stimulate the production in a subject animal of antibodies which bind (i.e., cross-react) to GnRH. The GnRH analog will preferably retain at least five consecutive amino acids from the GnRH decapeptide. The substitutions and insertions can be accomplished with natural or non-natural amino acids, and substitutions are preferably conservative substitutions made with amino acids which maintain substantially the same charge and hydrophobicity as the original amino acid. Moreover, the analog may itself be immunogenic or it may be coupled to an immunogenic carrier such as described hereinbelow.
GnRH or GnRH immunogenic analogs or mimics which are suitable for use herein have also been previously described for the immunocontraception of animals by Miller (U.S. patent application Ser. No. 10/833,903, now published as publication no. 2004/0191266, the contents of which are incorporated by reference herein). Suitable immunogenic analogs of GnRH have also been described, for example, in Meleon (U.S. Pat. Nos. 5,484,592 and 6,284,733), Mia (U.S. Pat. No. 4,608,251), Ladd et al. (U.S. Pat. No. 5,759,551), Hoskinson et al. (published PCT application WO8805308), and Russell-Jones et al. (U.S. Pat. No. 5,403,586) the contents of each of which are incorporated by reference herein. Thus, suitable GnRH analogs include but are not limited to GnRH peptides wherein the Gly at position 6 of the GnRH decapeptide has been replaced by a dextrorotary (D)-amino acid such as D-trp, D-glu, or D-lys (SEQ. ID NO. 2, 3, and 4, respectively); GnRH peptides wherein the p-Glu at position 1 of the GnRH decapeptide has been replaced by a Glu, His, or Pro (SEQ. ID NO. 5, 6, and 7, respectively); any continuous 5, 6, 7, 8, or 9 amino acid fragment of the GnRH decapeptide, such as pGlu-His-Trp-Ser-Tyr, pGlu-His-Trp-Ser-Tyr-Gly, pGlu-His-Trp-Ser-Tyr-Gly-Leu, His-Trp-Ser-Tyr-Gly-Leu-Arg, Trp-Ser-Tyr-Gly-Leu-Arg, Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH 2 , and Tyr-Gly-Leu-Arg-Pro-Gly-NH 2 (SEQ. ID NOS. 9-15, respectively); naturally occurring chicken GnRH II, pGlu-His-Trp-Ser-His-Gly-Trp-Tyr-Pro-Gly-NH 2 (SEQ. ID NO. 16); naturally occurring salmon GnRH, pGlu-His-Trp-Ser-Tyr-Gly-Trp-Leu-Pro-Gly-NH 2 (SEQ. ID NO. 17); the nona- or decapeptide (Cys)-Lys-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH 2 , wherein the amino terminal Cys is optional (SEQ. ID NOS. 18 and 19, respectively) or a dimer of the decapeptide wherein the amino terminal Cys are coupled to one another (SEQ. ID NO. 20); a polymer of two or more decapeptides in tandem of the formula Z 1 -Glx-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro[-Gly-X-Gln-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro] n -Gly-Z 2 wherein n is an integer greater than or equal to 1, X is a direct bond or a spacer, Z 1 -Glx is pGlu or Gln having an amino acid tail attached thereto for coupling to a carrier protein, and Gly-Z 2 is Gly-NH 2 or Gly having an amino acid tail attached thereto for coupling to a carrier protein (SEQ. ID NO. 21); and a peptide having the sequence pGlu-His-Trp-Ser-Tyr-Y-Leu-Arg-Pro-Gly-Gln-His-Trp-Ser-Tyr-Y-Leu-Arg-Pro-Gly-Cys wherein Y is independently Gly or a D-amino acid which may optionally contain an amino acid side chain attached thereto for coupling to a carrier protein (SEQ. ID NO. 22) or a dimer thereof.
Although the GnRH may be isolated from natural sources, for practical purposes GnRH or and its analogs may be synthesized by a variety of conventional methods Such techniques include but are not limited to methods well known to those skilled in the art of peptide synthesis, e.g., solution phase synthesis [see Finn and Hoffman. In “Proteins,” Vol. 2, 3rd Ed., H. Neurath and R. L. Hill (eds.), Academic Press. New York. pp. 105-253 (1976)), or solid phase synthesis (see Barany and Merrifield. In “The Peptides” Vol. 2. E. Gross and J. Meienhofer (eds.). Academic Press. New York. pp. 3-284 (1979)], or stepwise solid phase synthesis as reported by Merrifield [J. Am. Chem. Soc. 1963. 85: 2149-2154], the contents of each of which are incorporated herein by reference.
Conjugation of the GnRH or its analog to an immunogenic carrier in order to increase the immune response to the peptide may be conducted using previously described techniques, and a plurality carriers and carrier coupling techniques have been previously described for GnRH or its analogs. See for example, Meleon, Mia, Ladd et al., Hoskinson et al., and Russell-Jones et al. mentioned above. However, in a preferred embodiment, GnRH or an analog thereof is conjugated to immunogenic mollusk hemocyanin carrier protein, directly or indirectly through the C-terminal end of the GnRH or analog. Suitable immunogenic mollusk hemocyanin proteins include Concholepas concholepas hemocyanin protein, Keyhole Limpet ( Megathura crenulate ) hemocyanin protein (KLH), Horseshoe crab ( Limulus polyphemus ) hemocyanin protein, and Abalone ( Haliotis tuberculata ) hemocyanin protein, with KLH and Concholepas concholepas hemocyanin protein being preferred.
Conjugation of GnRH or its analog to the mollusk hemocyanin protein is preferably conducted using a cross-linking agent to allow a large number of GnRH or analog molecules (i.e., 200 or more) to be coupled to a single carrier protein molecule, effectively covering its outer surface with consistently aligned epitopes of the GnRH displaying the same basic conformation. To ensure this consistent alignment, the GnRH (or its analog) is coupled through its C-terminal end to the N-terminal end of the carrier protein through a bifunctional cross-linking agent. In a particularly preferred embodiment, the GnRH/carrier conjugate may be shown by the formula:
(X-A m -B-L) n -R (I)
wherein X is GnRH or a GnRH immunogenic analog, A is an optional amino acid spacer such as Gly, m is an integer greater than or equal to 0, B is an amino mercaptan, R is an intact immunogenic mollusk hemocyanin protein, L is a bifunctional crosslinking agent effective for simultaneously binding to the thiol of the mercaptan and to free amine moieties of the immunogenic mollusk hemocyanin protein, and n is an integer greater than or equal to about 200. A variety of amino mercaptans may be used, provided that it possesses a free amino moiety for binding to the C-terminal end of X (or A if present) and a free thiol moiety for binding to the bifunctional crosslinking agent, although cysteine is preferred. Preferred bifunctional crosslinking agents include succinimidyl-4-(N-maleimidomethyl)cyclohexane-1-carboxylate (SMCC) or sulfo-SMCC (s-SMCC), either of which form a maleimide-activated carrier protein. Other crosslinking agents suitable for conjugating the carrier protein and GnRH through the thiol group of the amino mercaptan include but are not limited to the organic solvent soluble agents Succinimidyl 4-(p-maleimidophenyl)-butyrate (SMPB), -[(γ-Maleimidobutyryl)oxy]succinimide ester (GMBS), -Succinimidyl[4-iodoacetyl]-aminobenzoate (SIAB), and m-Maleimidobenzyl-N-hydroxysuccinimide ester (MBS), or their corresponding water soluble sulfonated forms sulfo-SMPB (s-SMPB), sulfo-GMBS (sGMBS), sulfo-SIAB (s-SIAB), and sulfo-MBS (s-MBS).
Preparation of the above-mentioned GnRH/mollusk hemocyanin protein conjugate is preferably conducted under conditions of approximately neutral pH and high salt concentrations to prevent the disassociation of the protein into subunits, and thereby prevent mollusk protein epitopes from being exposed to the ferret's immune system. Thus, the protein is preferably dissolved in a buffer having an NaCl concentration greater than or equal to about 0.6 M, particularly about 0.9 M. Addition of sucrose to the carrier protein solution is also preferred to reduce the denaturation of the protein during freeze lyophilization processing and to allow the material to be rehydrated without precipitation. A detailed description of the conjugation procedure is provided in Example 2 of the above-mentioned published U.S. application no. 2004/0191266.
Treatment of a subject ferret with the carrier protein-conjugated GnRH or GnRH Immunogenic analogs is preferably initiated as soon as possible after diagnosis of ACD. Diagnosis is generally determined after the recognition of one or more clinical symptoms associated with this disease. Such symptoms include, but are not limited to one or more of adrenal hyperplasia, tumor growth, and significantly elevated levels of steroid hormones such as estradiol, 17-hydroxyprogesterone, androstenedione, and dehydroepiandrosterone. In an alternative preferred embodiment, the compound may be administered prophylactically to a ferret prior to development of clinical symptoms of ACD. Such prophylactic treatment may be initiated at any time or age after the ferret attains immunocompetence, which is normally after about 2 months of age. However, because neutered ferrets are particularly susceptible to development of ACD, the treatment of ferrets which have been neutered, or are to be neutered, is preferred.
The carrier protein-conjugated GnRH or GnRH Immunogenic analogs may be administered to the subject animal by parenteral injection (e.g., subcutaneous, intravenous, or intramuscular). Treatment of ferrets with the carrier protein-conjugated GnRH or GnRH Immunogenic analogs provides effective reduction in LH secretion and control of ACD in ferrets for periods of approximately a year or more after only a single dose or shot. Thus, a preferred dosage regimen comprises administration of a single dose per year, and may be continued for as long as desired, preferably for the life of the ferret. However, as a practical matter, it is recognized that treatment programs utilizing two or more doses per year may exhibit an even greater decrease in LH secretion and greater ACD control, and may therefore also be utilized. The method of this invention is effective for the treatment of both male and female ferrets.
The carrier protein-conjugated GnRH or GnRH Immunogenic analogs are prepared for administration by formulation in an effective amount or dosage with a pharmaceutically acceptable carrier or diluent, such as physiological saline, mineral oil, vegetable oils, aqueous carboxymethyl cellulose or polyvinylpyrrolidone, with physiological saline being preferred. However, when using compositions which include a mollusk hemocyanin carrier protein, the vaccine composition will preferably further include physiologically buffered saline with a high salt concentration to prevent dissociation of the protein. The salt (NaCl) concentration of the vaccine composition is preferably greater than or equal to about 0.7 M and less than or equal to about 1.0 M, and the pH of said vaccine composition is between about 7.0 and 8.0, with 7.4 being preferred. Appropriate adjuvants as known in the art may also be included in the formulation. Without being limited thereto, suitable adjuvants include but are not limited to mineral oil, vegetable oils, alum, Freund's incomplete adjuvant, Freund's incomplete adjuvant, and preferably the Mycobacterium avium subspecies avium in mineral oil adjuvant of Miller (U.S. patent application Ser. No. 10/833,903, now published as publication no. 2004/0191266, the contents of which are incorporated by reference herein). Other known immunogenic agents used in conventional vaccines for ferrets may also be included in the formulation.
The immunogenic GnRH or GnRH analogs are administered in an amount effective to reduce the secretion of LH by a subject ferret. As noted hereinabove, the administration of the immunogenic GnRH or GnRH analogs induces the ferret to produce antibodies against its own GnRH, which antibodies bind to endogenous GnRH, reducing or preventing GnRH stimulation of the pituitary, consequently reducing the release of LH (as well as FSH) which ultimately leads to the development of ACD. Thus, as used herein, an “effective amount” of the immunogenic carrier protein-conjugated GnRH or GnRH analogs is preferably defined as that amount which will induce antibodies against GnRH and thereby significantly reduce the release or secretion of LH in a treated ferret in comparison to untreated ferrets. A reduction of LH may be demonstrated by a significant reduction in the serum concentration of LH in treated ferrets in comparison with untreated control ferrets. While LH may be measured directly, in a preferred embodiment a decrease in LH is most readily determined qualitatively by measuring a decrease in serum steroid hormone levels, particularly androgens such as testosterone in males or progesterone in females. Moreover, because the development of ACD is due to this increase in LH secretion, it is also understood that a reduction in the secretion of LH may be evidenced by a significant reduction in one or more of the above-mentioned symptoms of ACD, as a reduction in alopecia, pruritus, swollen vulvas in females, sexual and aggressive behaviors, and possibly a reduction or slowing of adrenal hyperplasia and tumor growth in treated ferrets in comparison to untreated ferrets. Accordingly, the GnRH or GnRH analog conjugate may be administered in an amount effective to induce one or more of these responses as determined by routine testing. The actual effective amount will of course vary with the specific GnRH or GnRH analog, the immunogenic carrier and manner of conjugation, and the treatment regimen (i.e., treatment with only a single dose per year, or treatment with multiple doses per year), and may be readily determined empirically by the practitioner skilled in the art using an antigen dose response assay. For example, without being limited thereto, it is envisioned that suitable single shot doses of the GnRH or GnRH analog conjugate for the treatment of ferrets may be between about 200 μg and about 1800 μg per ferret, preferably between about 200 μg and about 800 μg, and most preferably about 500 μg The doses presented above are provided only as a guide for ferrets treated approximately yearly. For treatment programs utilizing two doses per year, it is envisioned that the doses described above for a single dose regimen could be cut in half for each dose.
The following examples are intended only to further illustrate the invention and are not intended to limit the scope of the invention which is defined by the claims.
Example 1
Materials and Methods
Eight pet ferrets with ACD of varying severity and duration (2 months) were vaccinated intramuscular (IM) with 0.5 ml (500 μg) of GnRH-KLH conjugate, formulated with the Mycobacterium avium subspecies avium in mineral oil adjuvant, prepared as described by Miller (Examples 1 and 2 of U.S. patent application Ser. No. 10/833,903, now published as publication no. 2004/0191266, the contents of which are incorporated by reference herein). As noted above, GnRH may be conjugated to several mollusk proteins but preferably KLH or blue mollusk protein. Before vaccination and at 2 and 3 months post vaccination, blood was collected for plasma hormone analyses and GnRH antibody concentrations.
The diagnosis of ACD was confirmed in the ferrets on the basis of clinical findings and results of a plasma hormone profile. Clinical findings included alopecia, pruritus, swollen vulva in females, and increased sexual behaviors and aggression. A subjective assessment of the severity of clinical signs at the start of the investigation (and later in response to vaccine treatment) were performed by comparing each ferret with a clinically normal ferret. Severity of alopecia (loss of hair) was estimated (100% representing full normal pelage and 0% representing whole body alopecia). Pruritus, vulvar size, sexual behavior, and aggression were evaluated as normal, decreased, no change, or increased.
Clinical response to vaccination was monitored via a physical examination performed monthly. At each examination, clinical evaluations and scoring of the severity of clinical signs in affected animals were performed.
Plasma samples obtained before treatment and at 2 and 3 months after treatment were analyzed for estradiol, androstenedione, and 17-hydroxyprogesterone concentrations. Reference ranges for hormones are as follows: estradiol, 30 to 180 pmol/L; androstenedione, 1 to 15 nmol/L; and 17-hydroxyprogesterone, 0.05 to 0.8 nmol/L (Rosenthal & Peterson. Evaluation of plasma androgens and estradiol concentrations in ferrets with hyperadrenocorticism. J Am Vet Med Assoc. 1996. 209:1097-1102; and Wagner & Dorn. Evaluation of serum estradiol concentrations in alopecic ferrets with adrenal gland tumors. J Am Vet Med Assoc. 1994. 205:703-707).
TABLE 1 0.5 ml IM Ferret GnRH Vaccination ACD Tx Study: 30-180 0-0.8 pmol/L 0-15 nmol/L Pre-GnRH nmol/L 17OH Estradiol Andro Prog 196.00 75.40 5.00 190.00 204.20 7.60 382.00 190.20 6.00 128 0.88 22.7 302.00 20.60 2.67 80 27.9 2.73 202.5 29 0.27 171.00 72.90 2.40 220.00 77.80 19.00 2 mos Post 17OH Response Response GnRH Estradiol Andro Prog 2 mo Post >2 mo titer @ 2 mo 79.00 9.40 0.20 100% 100% 128,000 131.00 3.80 0.27 80% 90% 32,000 129.00 9.10 0.12 100% 100% 128,000 93.00 9.10 0.30 100% 100% 128,000 135.00 2.10 0.15 80% 100% 32,000 79.00 2.40 0.20 20% 80% 8,000 85.3 11.2 0.88 40% 60% 32,000 120 3.5 0.12 100% 100% 128,000 190.00 6.30 1.61 0% 0% ND ND = non- detectable
Discussion of Results:
Vaccination with GnRH-KLH or GnRH-Blue protein resulted in a significant antibody titer against GnRH which in turn significantly dropped the androsterone and 17-OH progesterone concentration. A drop in both of these steroids reflected a drop in LH. The drop in LH was also reflected in the improvement of the clinical condition of the neutered ferret. The main clinical improvement was the regrowth of hair in the early stages of the disease. The drop in estradiol was not as dramatic as in the 17-OH progesterone and androsterone. This was probably due to the fact the GnRH does not suppress FSH as much as the LH.
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Adrenocortical disease (ACD) in ferrets develops as a result of the effect of increased concentration of Luteinizing Hormone (LH) on adrenal LH receptors. This increase in LH often results from the neutering of male or female ferrets. Neutered ferrets have no negative feedback of the ovarian or testicular hormone and as a result LH is elevated 3 to 10 times normal. Elevated LH may be prevented and/or treated by injection of GnRH vaccine. Administration of GnRH produces antibodies to endogenous GnRH. The GnRH-anti-GnRH immune-complex is ineffective in stimulating the release of LH and FSH in the anterior pituitary resulting drop in concentration of LH in the systemic circulation. This reduction in LH significantly reduces the occurrence or clinical symptoms of ACD therein. Moreover, treatment of ferrets with the GnRH provides long term relief from ACD for a period of a year or more.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to rotodynamic pumps of the type typically used for processing or handling slurries. Specifically, this invention relates to structures and methods for controlling the conditions and content of a chamber surrounding the mechanical seal arrangement used with equipment such as rotodynamic pumps.
[0003] 2. Description of Related Art
[0004] Rotodynamic pumps generally comprise an impeller which is connected to a drive shaft, and a pump casing in which the impeller rotates. Fluid processed by the pump can move to the area between the impeller and the drive side of the casing, around the drive shaft. Therefore, a mechanical seal arrangement is provided for sealing the drive shaft from leakage of fluid around the drive shaft. The mechanical seal of the drive shaft is often cooled and/or lubricated with a liquid flushed near the seal. Sometimes, the fluid used for flushing the system is that which is being processed by the pump. Thus, flushing systems in conjunction with mechanical seals in clear water and chemical processing pumps are well known.
[0005] Exemplar flushing systems are disclosed in U.S. Pat. No. 5,605,436 to Pedersen and U.S. Pat. No. 5,772,396 to Rockwood. The '396 patent exemplifies a seal construction where soft seal faces are employed an annulus is formed between the seal rotating face and the stationary stuffing box. One resulting effect of the '396 configuration is a high potential for dry running at the seal face if flushing of the seal is not continuously maintained.
[0006] In rotodynamic pumps that process fluid with entrained solids, i.e., slurries, the mechanical seal is also subject to wear from solids coming into contact with the seal. In certain rotodynamic pumps that are used for processing slurries, an expanded area, or seal chamber, may be provided around the mechanical seal. The enlarged seal chamber, defined generally between the back of the impeller and the pump casing, provides a stilling chamber and seal environment which is relatively high in pressure, low in air and low in turbulence. The seal chamber also provides an area through which fluid that is processed by the pump can be circulated at a lower velocity and, hence, higher pressure, to cool and/or clean the seal mechanism.
[0007] In some systems, the cooling fluid is pumped into the seal chamber at increased pressures to keep the flushing fluid moving out of the seal chamber toward the pump casing. In others, a fluid is caused to circulate in a sweeping manner in the seal chamber to cool the seal faces, as disclosed in U.S. Pat. No. 5,195,867 to Stirling. In the '867 patent, pumped fluid is circulated through the seal chamber at a low velocity and relatively high pressure to increase the likelihood that the seal chamber will operate in a positive pressure and to reduce the likelihood of air collecting, since air will always pass from a high pressure area to a low pressure area.
[0008] With certain types of slurries, however, particularly those that contain high concentrations of air, solids or a suspension of air and solids, pockets of air can collect in the area of the seal faces and cause a dry running condition. Further, collection of solids about the seal faces can cause wear on the mechanical seal or, if the solids accumulate to a large enough size, the accumulated large solids can break off the surfaces within the seal chamber and damage the seal faces. Failure of the mechanical seal can, therefore, be caused by dry running conditions, by wear due to exposure to solids accumulated in the seal chamber or by actual damage brought about by collision with large agglomerations of solids.
[0009] Known flushing or cooling systems for mechanical seals are not structured to address these problems. For example, known systems may include one or more flushing apertures positioned near the seal faces to cool or lubricate the seal face, but such apertures are not structured to control the amount of flushing liquid delivered to the seal face, and actual damage to the seal face can occur if, for example, cooling liquid strikes a high temperature seal that has been running under dry conditions. Nor are known flushing systems structured or positioned to remove or condition solids accumulations in the seal chamber. Additionally, known flushing systems, when flushed with a solids-containing fluid in close proximity to a seal face, can cause wear or damage. These known flushing systems need to operate continuously to allow the seal to function. Failure or interruption of the flushing system will ultimately cause the seal to fail.
[0010] Therefore, it would be advantageous in the art to provide a seal chamber conditioning mechanism for modifying the condition or content of the seal chamber, particularly responsive to known conditions in the seal chamber that might potentially cause damage to the mechanical seal, such as dry running conditions or potentially damaging solids accumulation. Further, it would be beneficial to provide a system which operates intermittently to clean and/or condition the seal chamber in order to minimize the dilution of the slurry mixture, and one which operates as needed depending on the conditions of the seal chamber.
BRIEF SUMMARY OF THE INVENTION
[0011] In accordance with the present invention, a valve mechanism, positioned in the seal chamber of a rotodynamic pump, is structured to provide selective modification of the contents or condition of the seal chamber to assure proper operation and condition of the mechanical seal at all times, thereby improving the seal life of the pump. While the seal chamber conditioning valve mechanism of the present invention is described for use in a centrifugal pump of the slurry type, the valve mechanism may be adapted for use in other types of equipment that use mechanical seals. including for example, clear liquid pumps and turbines.
[0012] The valve mechanism of the present invention is comprised of a housing that is positioned, at least partially, in the seal chamber of a rotodynamic pump to effect delivery of fluid to the seal chamber, including the seal faces of the mechanical seal. The valve mechanism further comprises a first end having a selectively movable valve and valve seat which are oriented inwardly to the seal chamber. In an exemplar embodiment of the invention, the valve is biased by spring means to be registered against the valve seat. Other devices for selectively moving the valve relative to the valve seat may be implemented.
[0013] A second end of the housing, opposite the valve seat, is positioned to reside outside the seal chamber, and is preferably accessible from outside the pump casing of the pump. An opening at the second end provides access to the biased valve such that the valve can be manually operated. Additionally, the opening at the second end of the housing may preferably be threaded to receive a similarly threaded conduit, such as a hose or pipe fitting, that delivers fluid to the valve housing. The fluid delivered by the conduit is pressurized to cause the valve to disengage from the valve seat, thereby providing fluid to the seal chamber. The fluid may be provided from, for example, a pressurized tank or source other than the pump. Alternatively, the conduit may be connected at its other end to the outlet of the pump so as to deliver fluid processed by the pump to the valve for delivery to the seal chamber. As used herein, “fluid” may include both liquid, gas or mixtures thereof. The valve mechanism may include a pressure and flow limiting device that modifies the flow of fluid through the valve.
[0014] The valve is generally conically shaped, thereby effecting a conical-like spray of fluid into the seal chamber. Consequently, the positioning of the valve mechanism in the seal chamber and the conical-like spray pattern produced by the valve enables fluid to be delivered about the surfaces of the seal chamber to flush down and remove accumulated solids from the surfaces of the seal chamber. The valve mechanism is also directed to spray in the direction of the seal face of the mechanical seal to provide cooling and lubrication of the seal face. The valve mechanism is also positioned in the seal chamber to enable the conical-like spray of the valve to break up large air bubbles and to disperse the toroidally-shaped air bubble mass that may form about the pump shaft at high air concentrations. The dissipation of air bubbles from the area causes the seal chamber environment to improve by modifying the seal chamber condition to a more homogeneous mixture of fluid and solids.
[0015] The valve mechanism, as noted above, is selectively operable manually or by introduction of pressurized fluid to the second end of the valve mechanism. As such, the valve mechanism can be manually actuated to open the valve and thereby effect a discharge from the seal chamber as may be required to modify the solids or gas (e.g., air) content of the seal chamber.
[0016] When an external source of fluid is provided, via a fluid conduit, to the valve mechanism, the configuration of the valve assures that the valve will center properly on the valve seat and will close properly. Application of pressurized fluid to the housing provides a flushing of the valve housing to eliminate the accumulation of solids in the valve housing.
[0017] The spring-loaded construction of the valve, in an exemplary embodiment of the invention, enables the valve to close if excessive pressurization of the valve occurs. That is, the conical spring that seats the valve will close upon itself if the amount of pressure exerted on the valve exceeds a selected load on the conical spring. Automatic closure of the valve mechanism prevents excessive flow of pressurized fluid and prevents excessively high pressure flushing fluid from reaching the seal chamber and seal face, which would introduce undesirable turbulence into the seal chamber. The conical spring about the valve has an added advantage of acting as a restrictive orifice such that as pressure rises in the valve housing and the valve opens, the coils of the spring close together limiting the flow of fluid through the valve mechanism. Thus, the conical spring provides a pressure and flow limiting device. The coil spring is also self-cleaning since solids cannot build up around the spring as it flexes.
[0018] The number of valve mechanisms positioned in the seal chamber may vary. Preferably, however there may be at least three valve mechanisms evenly spaced circumferentially about the drive shaft. As many as six or more valve mechanisms may be evenly spaced about the drive shaft. All of the valve mechanisms may operate similarly to both selectively introduce or discharge fluid from the seal chamber. Alternatively, some of the valve mechanisms may be selectively actuated to discharge contents from the seal chamber while others may be selectively actuated to introduce flushing media into the seal chamber in, for example, an alternating pattern of valves about the drive shaft. Still other valve mechanisms may be used to monitor conditions of the seal chamber, such as pressure, temperature and the presence of, for example, air and excessive solids.
[0019] The seal chamber conditioning valve mechanism of the present invention can be selectively actuated to either discharge contents from or introduce flushing fluid into the seal chamber upon determination of a particular condition within the seal chamber or the seal faces. That is, upon determination, for example, that too much gas is present in the seal chamber, thereby potentially leading to the formation of a gas bubble and dry running of the mechanical seal, some or all of the valve mechanisms may be manually actuated to release gas from the seal chamber, while others may be actuated to introduce flushing fluid into the seal chamber to dissipate the larger air pockets and lubricate or cool the seal face. The determination of the condition or status of the environment within the seal chamber may be monitored by any suitable means, such as a thermocouple. A monitoring element may be positioned in the seal chamber, preferably at or near the seal face.
[0020] It is the unique ability to selectively actuate the seal chamber conditioning valve mechanism of the present invention to modify the condition of the environment within the seal chamber or modify its contents that presents an improvement in preservation and maintenance of the mechanical seal in rotodynamic pumps. That is, the ability to determine stress on or imminent failure of the seal due to adverse conditions in the seal chamber, and to modify the conditions within the seal chamber to save the seal, provides the most significant advantage via the present invention. These and other advantages will become more apparent upon reference to the description provided hereinafter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0021] In the drawings, which currently illustrate the best mode for carrying out the invention:
[0022] FIG. 1 is a view in longitudinal cross section of a centrifugal pump illustrating the general elements of the pump, including the seal chamber, and the position of the conditioning valve of the invention;
[0023] FIG. 2 is an enlarged view in longitudinal cross section of the seal chamber of the pump further illustrating the detail of the conditioning valve;
[0024] FIG. 3 is an enlarged view in cross section of the seal chamber conditioning valve of the present invention; and
[0025] FIG. 4 illustrates schematically an embodiment of the invention which employs a system for monitoring conditions within the seal chamber.
DETAILED DESCRIPTION OF THE INVENTION
[0026] FIG. 1 illustrates, in partial cross section, a centrifugal pump 10 of the type used to process slurries. The pump 10 generally comprises a pump casing 12 which, in turn, comprises a volute casing 14 to which is attached to a suction inlet casing 16 . As shown, the volute casing 14 may preferably comprise a front casing 18 and a back casing 20 . In the particular embodiment of the pump 10 shown, casing liners 22 , 24 are installed on the inner surface of the front casing 18 and back casing 20 . The pump 10 further comprises a frame plate adaptor 28 that attaches to the back casing 20 . A frame plate liner insert 30 is positioned adjacent the frame plate adaptor 28 .
[0027] An impeller 32 is positioned in the pump casing 12 and is secured to a pump shaft 34 that extends through the frame plate adaptor 28 . The pump shaft 34 also extends through a bearing housing 36 in which is located a set of bearings (not shown) which support the pump shaft 34 . The pump shaft 34 is also keyed for attachment to a motor or drive belt mechanism (not shown). The features of a pump bearing housing 36 and motor are well-known in the art and are not discussed in further detail herein, but will be known to those of skill in the art.
[0028] A mechanical seal 40 is positioned about the pump shaft sleeve 58 at the point of extension of the pump shaft 34 through the frame plate adaptor 28 . The mechanical seal 40 prevents fluid from leaking out of the pump 10 and around the pump shaft 34 . In this particular embodiment of a slurry pump 10 , the pump 10 is configured with a seal chamber 42 that comprises an enlarged area about the mechanical seal 40 . The relative positioning of a seal chamber conditioning valve mechanism 44 of the present invention is illustrated in FIG. 1
[0029] It can be appreciated from the view of the pump 10 in FIG. 1 that fluid enters the inlet 48 of the pump 10 by suction created by the rotation of the impeller 34 within the casing 12 . The impeller 32 directs the fluid into the volute 14 where it is discharged from an outlet (no shown) tangentially oriented to the volute. The pressure of the processed fluid causes fluid to travel through a gap 50 formed between the back shroud 52 of the impeller and frame plate liner insert 30 of the pump 10 , and into the seal chamber 42 . Solids and gases are typically entrained in the fluid. Solids may then build up in the seal chamber and may even accumulate on the frame plate liner insert 30 and the back shroud 52 of the impeller 34 . This condition causes the seal face temperature to rise. Removal of the solids and gases is then required to keep the seal from failing. The valve mechanism 44 of the present invention thus serves to quickly modify the condition or contents of the seal chamber to allow the seal to continue to operate without leakage until the cause of the problem is corrected.
[0030] FIG. 2 provides an enlarged view of one half of the pump shaft 34 and seal chamber 42 , better illustrating the elements of the mechanical seal 40 and valve mechanism 44 . As previously described, the pump shaft 34 is connected to the impeller 32 by appropriate means, here illustrated as a threaded engagement 56 . A pump shaft sleeve 58 surrounds the pump shaft 34 and is positioned axially between the hub portion 59 of the impeller 32 and a release collar 60 . Both the pump shaft sleeve 58 and release collar 60 rotate with the pump shaft 34 .
[0031] The mechanical seal 40 comprises a mechanical seal sleeve 62 that is positioned about the pump shaft sleeve 58 and rotates with the pump shaft sleeve 58 . A rotating seal face holder 64 is secured to the mechanical seal sleeve, as shown in FIG. 2 , and rotates with the mechanical seal sleeve 62 . The rotating seal face holder 64 provides support for a mechanical seal rotating face 66 which rotates with the rotating seal face holder 64 . A stationary mechanical seal face 68 abuts the mechanical seal rotating face 66 and thereby defines a seal face 70 therebetween. The stationary mechanical seal face 68 is secured to a mechanical seal gland plate 74 by means of a plurality of drive pins 76 . Though not shown, a plurality of biasing springs are positioned between the mechanical seal gland plate 74 and the stationary mechanical seal face 68 to maintain a tight fit between the stationary seal face 68 and rotating face 66 at the seal face 70 . An o-ring 78 is also positioned between the mechanical seal gland plate 74 and the stationary mechanical seal face 68 to prevent leakage of fluid therebetween.
[0032] The seal chamber conditioning valve mechanism 44 of the present invention is shown positioned through an opening 80 formed in the mechanical seal gland plate 74 . While only one valve mechanism 44 is shown, it is understood that a plurality of such valve mechanisms 44 may preferably be distributed circumferentially around the pump shaft 34 and positioned, as shown, through the gland plate 74 . The valve mechanism 44 may preferably be threadingly received into the opening 80 of the gland plate 74 . An o-ring 82 is positioned between the valve mechanism 44 and the threaded opening 80 . The valve mechanism 44 comprises a housing 90 which has a first end 92 that is oriented toward the interior of the seal chamber 42 and a second end 94 that is positioned external to the pump casing 12 thereby providing access to actuation of the valve mechanism 44 .
[0033] Further detail of the seal chamber conditioning valve mechanism 44 can be seen in FIG. 3 where, notably, the housing 90 is provided with a threaded neck portion 96 that is received into a correspondingly threaded opening 80 ( FIG. 2 ) in the gland plate 74 . It can also be seen that the housing 90 is formed with an internal bore 98 that extends from the first end 92 to the second end 94 of the valve mechanism 44 . At the first end 92 of the valve mechanism 44 , the internal bore 98 defines a valve seat 100 against which a valve 102 registers when the valve mechanism 44 is in a closed position, as illustrated.
[0034] The valve 102 is connected to a valve stem 106 that is concentrically positioned within the bore 98 of the housing 90 . In the particular embodiment illustrated, the valve stem 106 is a hex flange bolt having a flanged hex head 108 at a first terminal end 110 against which the valve 102 is positioned. A flat washer 112 and locknut 114 are threaded onto the opposing second end 116 of the valve stem 106 . A conically configured spring 120 is positioned to encircle the valve stem 106 and is biased between the flat washer 112 and an inwardly extending shoulder 122 of bore 98 .
[0035] A second end 126 of the housing 90 of the valve mechanism 44 is configured as a threaded female coupling 126 to which a fluid conduit, such as a hose or other pipe fitting (not shown), may be attached for introducing fluid into the valve mechanism 44 . The coupling 126 also provides an opening through which access may be made to the second end 116 of the valve stem 106 for manually actuating the valve 102 , as described more fully below.
[0036] The valve 102 is conically shaped and the valve seat 100 against which the valve 102 registers is configured with a complimentary conical shape. Consequently, when fluid is introduced into the bore 98 of the valve housing 90 through the coupling 126 , the pressure of the fluid causes the valve 102 to move out of registration with the valve seat 100 and a conically shaped spray is produced.
[0037] Referring to FIG. 2 , it can be seen that the first end 92 of the housing 90 of the valve mechanism 44 is flush with the inner-facing surface 130 of the gland plate 74 . The valve mechanism 44 is, therefore, positioned to provide a conical spray to the gland plate 74 and the seal face 70 to wash away solids, and particularly solids that may have accumulated on those surfaces or structures. The distribution of a plurality of such valve mechanisms 44 circumferentially about the pump shaft 34 ensure that the seal chamber 42 is substantially flushed of solids. The distribution of the valve mechanisms 44 about the pump shaft 34 further assures a comprehensive dissipation of large air pockets that might have formed in the seal chamber 42 , particularly in the area of the seal face 70 . The conical spray provided by the valve 102 breaks larger air pockets into smaller bubbles that are dispersed more effectively into the contents of the seal chamber 42 . The position of the first end 92 of the valve housing 90 flush with the surface 130 of the gland plate 74 also avoids the production of turbulence in the seal chamber when displacement fluid is being introduced by the conical spray.
[0038] The conical shape of the valve 102 also enables an even flow of fluid through the bore 98 of the housing 90 and about the valve stem 106 . This factor assures that solids are flushed from the valve mechanism 44 . The conical shape of the spring 120 , in combination with the conical shape of the valve 102 , further assures that the valve stem 106 remains centered in the housing 90 and the conical shape of the spring 120 provides a pre-loaded condition that assures proper closing of the valve 102 against the valve seat 100 .
[0039] Displacement fluid can be introduced into the coupling 126 of the valve mechanism 44 from a variety of sources. For example, process fluid can be taken from the outlet of the pump and circulated into the valve mechanism 44 by conduit means known in the industry. The displacement fluid can also be in the form of a gas or liquid supplied from an external source, such as a tank.
[0040] The valve mechanism 44 of the present invention is also structured to be manually actuated by accessing the valve stem 106 through the coupling 126 . This may be accomplished by insertion of a tool through the coupling 126 that engages the second end 116 of the valve stem 106 , thereby enabling movement of the valve stem 106 for disengagement of the valve 102 from the valve seat 100 . The manual actuation of the valve mechanism 44 enables the valve mechanism 44 to be opened for discharge of air, fluid and solids from the seal chamber 42 as may be required. Once air, fluid and solids are discharged through the valve mechanism 44 , any residual solids can be flushed from the valve mechanism 44 by closing the valve 102 and introducing fluid, from a fluid conduit connected to the coupling, into the valve housing 90 .
[0041] The conditions of the seal chamber 42 and the seal face 70 may be monitored by any appropriate monitoring apparatus 120 or means to enable the valve 44 to be intermittently actuated as required to modify the conditions or content of the seal chamber 42 . As illustrated schematically in FIG. 4 , such monitoring apparatus may include, for example, a thermocouple 122 positioned at or near the seal face 70 . The thermocouple 122 is capable of monitoring the temperature at the seal face 70 and producing a signal that is transmitted, such as by wire 126 , to a control device 128 located outside the casing 12 of the pump. The control device 128 is in electrical and/or mechanical communication, such as via wire 132 , with a solenoid valve 136 connected to the conditioning valve mechanism 44 .
[0042] Thus, when data is sent from the thermocouple 122 to the control device 128 concerning the condition of the seal face 70 or the seal chamber 42 , such as temperature, the control device 128 processes the data and determines when it may be appropriate to signal the valve 102 to open via action of the solenoid 136 . The valve 102 opens to either allow discharge of some of the contents of the seal chamber 42 or to allow introduction of fluid through the valve mechanism 44 into the seal chamber. The control device 128 can, therefore, also control a source of fluid to provide that fluid to the valve housing 90 as conditions dictate. One or more control devices 128 can be used to operate a plurality of valves 44 , and the control devices 128 can be made to intercommunicate data between the devices 128 .
[0043] A centrifugal pump may be structured with a plurality of valve mechanisms 44 encircling the pump shaft 34 , as described, where all of the valve mechanisms 44 are actuated at the same time and in the same manner. That is, all valve mechanisms 44 may be simultaneously actuated together to either introduce fluid into the seal chamber 42 or to discharge fluid from the seal chamber 42 . Alternatively, the valve mechanisms 44 may be actuated individually or in alternating series (e.g., every other valve mechanism 44 being actuated to introduce fluid into the seal chamber 42 ) to provide a conditioning effect within the seal chamber 42 that is unique to the current condition of the seal chamber 42 .
[0044] While the seal chamber conditioning valve mechanism of the present invention is particularly suited for modifying the conditions and content of a seal chamber in a centrifugal slurry pump, the valve mechanism of the invention may be adapted for use in any number of other types of pumps and for other purposes. Hence, reference herein to specifics of the structure and positioning of the valve mechanism of the invention is by way of example only and not by way of limitation.
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In a rotodynamic pump, a seal chamber conditioning valve mechanism is positioned at least partially within the seal chamber of the pump to selectively and intermittently deliver fluid to or discharge contents from the seal chamber to modify the condition or content of the seal chamber and effectively protect the mechanical seal from failure due to, for example, built up solids or the presence of air. The conditioning valve mechanism may be actuated by a control device in communication with monitoring apparatus that determines the condition of the seal chamber, and particularly the mechanical seal face.
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CROSS-REFERENCE TO RELATED APPLICATION
The present application claims the benefit of the filing date of provisional U.S. patent application No. 61/868,838 filed Aug. 22, 2013. The entire disclosure of the provisional application is hereby incorporated herein by this reference.
BACKGROUND OF THE INVENTION
In representatively illustrated embodiments thereof, this invention provides connector apparatus for telescoped ground engaging wear and support members. The connector apparatus is self-adjusting, to re-tighten the interfit between the wear and support members in response to operational forces imposed on the wear member.
A long standing practice in the ground engaging art is to protect a support member from operational abrasion wear by telescoping a replaceable wear member rearwardly onto a front portion of the support member (typically larger and more expensive than the wear member) to shield the wear member-covered portion of the support member from abrasion when the wear member/support member assembly is utilized in, for example, excavation, earth moving or mining operations. Examples of such telescoped wear member/support member combinations utilized in the ground engaging art include, but are not limited to, tooth point/adapter assemblies, base adapter/intermediate adapter assemblies, and shroud/bucket lip weld base assemblies.
For the wear member portion of the assembly to perform its abrasion shielding function, it must be releasably retained on the support member in a manner such that it will not be dislodged from the support member during ground engaging operations, yet is easily removable from the support member when the wear member is substantially worn away and needs to be replaced with a new wear member. Several well-known problems, limitations and disadvantages are commonly associated with conventional methods and apparatus utilized to retain a wear member on an associated support member.
For example, such retention is often effected using a spool member placed in aligned wear and support openings in the telescoped wear and support members, and a wedge which is then pounded into place in the openings into forcible engagement with the spool to retain the wear member on the support member. This requirement for pounding in a connector member is typically awkward and can sometimes be dangerous. Moreover, pounded-in connector components may be loosened during use of the wear member/support member assembly to an extent that the wear member falls off, becomes lost, and subjects the underlying support member to undesirable wear. Also, such loosening can undesirably permit the wear member to rattle back and forth on the support member. Undesirable loosening of the interfit between the wear and support members may also occur due to internal operational abrasion therebetween, with the pounded-in connector components typically being unsuitable for easily re-tightening this interfit.
As can readily be seen from the foregoing, a need exists for improved wear member/support member connector apparatus that eliminates or at least substantially reduces above-mentioned problems, limitations and disadvantages associated with conventional connector apparatus of the type generally described above. It is to this need that the present invention is primarily directed.
In carrying out principles of the present invention, in accordance with representatively illustrated embodiments thereof, telescoped wear and support members are provided with specially designed self-adjusting connector apparatus that releasably retains the wear member in its rearwardly telescoped orientation on the support member. As will be seen, in representative embodiments thereof the connector apparatus preferably includes cooperating ratchet structures operatively associated with the support and wear members and functioning to automatically tighten an abrasion-created loosened interfit between the wear and support members in response to a rearwardly directed operational force imposed on the wear member.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinally foreshortened, partially exploded side elevational view of a telescoped ground engaging wear member and support member assembly incorporating therein a self-adjusting interfit tightening structure embodying principles of the present invention;
FIG. 2 is a top side view of a base member portion of the interfit tightening structure;
FIG. 3 is an exploded bottom side view of the wear member and base member as shown in FIG. 1 ;
FIG. 4 is a cross-sectional view of the interfit tightening structure;
FIG. 5 is an enlarged cross-sectional view of a portion of the assembled interfit tightening structure;
FIG. 6 is a cut away perspective view of a portion of a second wear member and support member assembly incorporating therein an alternate embodiment of the self-adjusting interfit tightening structure;
FIG. 7 is a cross-sectional view through a portion of the second wear member and support member assembly taken generally along line 7 - 7 of FIG. 6
FIG. 8 is a partially exploded bottom side view of a portion of the second wear member and support member assembly;
FIG. 9 is an end view of the assembled FIG. 8 components taken along line 9 - 9 of FIG. 8 ;
FIG. 10 is an upwardly directed cross-sectional view through a portion of the second wear member and support member assembly; and
FIG. 11 is a cross-sectional view through the second wear member and support member assembly taken along line 11 - 11 of FIG. 10 .
DETAILED DESCRIPTION
Referring initially to FIGS. 1-5 , in a first representatively illustrated embodiment of the self-adjusting connector apparatus one way ratchet teeth 10 (see FIGS. 3-5 ) are formed on a top side interior portion of a hollow wear member 12 , illustratively in the form of a wing shroud, which is rearwardly telescoped onto a base member 14 (see FIGS. 1, 4 and 5 ) illustratively welded onto or otherwise secured to a support member 15 onto which the wear member 12 is also telescoped. Illustratively the support member 15 is in the form of a bucket lip to which the wear member 12 is releasably held by a specially designed interfit tightening structure 16 embodying principles of the present invention. Other types of support members may be alternatively utilized without departing from principles of the present invention.
Interfit tightening structure 16 (see FIGS. 4 and 5 ) includes the ratchet teeth 10 , a vertically movable metal contact block 18 having a series of projections 20 formed on its top side in staggered rows as shown in FIG. 2 , and an elastomeric member 22 underlying the block 18 . The elastomeric member 22 and a reduced cross-section lower portion 18 a of the contact block 18 are slidably received in a top side recess 24 of the base member 14 .
A bolt 26 has a head portion 28 rotatably received in a top side opening of the contact block 18 and having a noncircularly cross-sectioned drive recess 30 therein, and a body portion 32 extending downwardly through the a bottom portion of the contact block 18 and the underlying elastomeric member 22 and threaded into a nut 34 (see FIG. 5 ) nonrotatably received in a lower side opening 36 of the support member 14 . Tightening the bolt 26 vertically compresses the elastomeric member 22 and lowers the contact block 18 , and subsequently loosening the bolt 26 relaxes the elastomeric member 22 and permits it to raise the contact block 18 . Instead of the illustrated single nut 34 , two nuts could be utilized to further assure that the bolt 26 stays in place during operation of the ground engaging apparatus.
With the elements 18 , 22 , 26 and 34 installed on the base member 14 , and the bolt 26 tightened to lower the contact block 18 against the resilient force of the compressed elastomeric member 22 , the wear member 12 is rearwardly telescoped onto the base member 14 (and also onto the support member 15 ) to an initially tightened orientation on the base member 14 and thus on the support member 15 as well. Using a suitable tool (not shown) moved downwardly through an access opening 38 in the top side of the wear member 12 and into the bolt head recess 30 , the bolt 26 is then loosened to permit the contact block 18 to be raised by the underlying elastomeric member 22 in a manner causing the contact block projections 20 to upwardly enter corresponding ones of the gaps between adjacent pairs of the one-way ratchet teeth 10 of the wear member 12 (see FIG. 5 ). Due to the one-way configuration of the ratchet teeth 10 , this prevents the installed wear member 12 from moving forwardly relative to the base member 14 and coming off the support member 15 to which the base member 14 is secured.
As the wear member/support member assembly 12 , 15 is utilized in ground engaging operations, operational abrasion wear between these elements will loosen the original interfit therebetween. However, when this interfit loosening reaches a certain extent, rearwardly directed operational forces on the wear member 12 will shift it rearwardly in a manner causing the projections 20 to rearwardly ratchet into the next available set of grooves between the one-way ratchet teeth 10 , thereby again locking the wear member 12 against forward movement relative to the support member 15 and retightening the wear member 12 thereon.
A second interfit tightening structure embodiment 40 is shown in FIGS. 6-11 and is similar in operation to that of the previously described interfit tightening structure 16 . Specifically, the interfit tightening structure 40 (see FIGS. 6, 7, 10 and 11 ) automatically functions to tighten a loosened interfit between a wear member 42 , representatively in the form of a wing shroud, telescoped onto a base member 44 welded or otherwise secured to a support member 45 illustratively in the form of an excavating bucket lip, in response to rearwardly directed operational force exerted on the wear member 42 .
In this interfit tightening structure embodiment 40 , however, a set of one-way ratchet teeth 46 (see FIG. 8 and) is formed directly on a right side edge portion of the base member 44 (as viewed in FIG. 10 ) and cooperates with projections 48 on a metal contact block 50 similar to the previously described contact block 18 and secured with an underlying resilient member 52 by a bolt 54 within an internal side edge recess 56 of the base member 44 (see FIG. 6 ). As can be seen in FIGS. 6, 7 and 10 , rearward movement of the wear member 42 relative to the support member 44 caused by rearwardly directed operational forces on the wear member 42 ratchets it rearwardly to retighten it on the base member 44 and thus on the support member 45 to which the base member 44 is welded or otherwise secured. If desired, a second interfit tightening structure 40 (not shown) may be installed on the left side edge portion of the wear member 42 (as viewed in FIG. 10 ), with its projections 48 staggered in a front-to-rear direction relative to the projections 48 on the right side interfit tightening structure 40 , for mating with one way ratchet teeth 46 (not shown) formed on the left side edge of the base member 44 . As illustrated, the projections 48 may have one-way ratchet tooth configurations (as may the previously described projections 20 ).
As will be readily appreciated by those of skill in this particular art, the horizontally oriented interfit tightening structure depicted in FIG. 6 could be alternatively utilized in a vertical orientation, if desired, simply by rotating it ninety degrees in a manner placing the bolt 54 on the top side of the re-oriented interfit tightening structure.
While the representative embodiments of the present invention have been previously described herein in conjunction with a shroud structure connected to a weld base structure in turn secured to a bucket lip, principles of the invention are not limited to these illustrative types of wear and support members and could be utilized to advantage with a wide variety of other types of wear and support member combinations such as, for example, a tooth point and an adapter or an intermediate adapter and a base adapter.
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Telescoped ground engaging telescoped wear and support members are provided with self-adjusting connector apparatus that releasably retains the wear member in a rearwardly telescoped orientation on the support member. In illustrated embodiments thereof, the connector apparatus includes cooperating ratchet structures operatively associated with the support and wear members and functioning to automatically re-tighten an abrasion-created loosened interfit between the wear and support members in response to a rearwardly directed operational force imposed on the wear member.
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FIELD
This application is a divisional application of, and claims all rights and priority on prior pending U.S. patent application Ser. No. 12/631,260 filed 2009, Dec. 04, which was a divisional application of U.S. Pat. No. 7,649,365 issued 2010, Jan. 19, of which all rights and priority are also claimed. This invention relates to the field of photovoltaics. More particularly, this invention relates to the inline inspection of photovoltaic films.
BACKGROUND
Photovoltaics can be made from a variety of different materials and by way of a variety of different processes. One of the more promising fabrication methods—from a cost standpoint at least—is to form continuous webs of photovoltaic material that are sequentially processed as the web moves along a production line. Thus, various layers of the photovoltaic devices are sequentially formed, one on top of another, as the web of built-up material progresses down the moving production line. Another fabrication method is to deposit the photovoltaic film on plate glass, which is the preferred method to fabricate CdTe solar cells.
In the past, electrical defects in the photovoltaic film have been studied by removing a sample from the production material and inspecting the sample offline. Removing a sample often introduces serious defects near the edges of the remaining photovoltaic material where the sample was removed.
Further, examining the sample offline means that the information cannot be readily used in an automatic feedback loop for control of the film deposition processes. Further, such offline testing is time consuming, which results in a potential greater loss of material, in the event of a process excursion.
What is needed, therefore, is a system that overcomes problems such as those generally described above, at least in part.
SUMMARY
The above and other needs are met by inline inspection of the photovoltaic film for electrical anomalies without removing samples. A first electrical connection is formed to a first surface of the photovoltaic material, and a second electrical connection is formed to an opposing second surface of the photovoltaic material. A localized current is induced in the photovoltaic material, and properties of the localized current in the photovoltaic material are sensed using the first and second electrical connections. The properties of the sensed localized current are analyzed to detect the electrical anomalies in the photovoltaic material.
In various embodiments according to this aspect of the invention, at least one of the first electrical connection and the second electrical connection is formed using a physical contact to the photovoltaic material. In some embodiments, at least one of the first electrical connection and the second electrical connection is formed using a non-physical contact to the photovoltaic material. In yet other embodiments, the first electrical connection is formed using at least one of a laser and an electron beam.
According to another aspect of the invention there is described a method of inspection by applying an ultraviolet probe laser to a location of the photovoltaic material, where the probe laser is applied at a probe energy sufficient to emit photoelectrons from a conduction band of the photovoltaic material into a vacuum environment, but the probe energy is insufficient to substantially excite electrons from a valence band of the photovoltaic material into a vacuum environment, and simultaneously applying a visible pump laser to the same location of the photovoltaic material, where the pump laser is applied at a pump energy sufficient to excite photoelectrons from the valence band of the photovoltaic material to the conduction band, but the pump energy is insufficient to substantially emit photoelectrons from the conduction band of the photovoltaic material into the vacuum environment, sensing the photoelectrons that are excited into the vacuum environment to measure a current, and interpreting fluctuations in the current as electrical anomalies as a function of position on the photovoltaic surface.
In various embodiments according to this aspect of the invention, the photovoltaic material does not include a contact film at the location of the application of the probe laser. In some embodiments, the probe laser is applied to a first side of the photovoltaic material and the pump laser is applied to a second side of the photovoltaic material.
In other embodiments, both the probe laser and the pump laser are applied to a first side of the photovoltaic material through a transparent port into the vacuum environment, where an interior surface of the transparent port is coated with a transparent conductive material that is disposed in proximity to the photovoltaic material sufficient to receive and sense the photoelectrons emitted from the photovoltaic material, and the transparent conductive material is disposed in sections on the transparent port, where the sections are electrically isolated one from another, thereby enabling separate measurement of the emitted photoelectrons based on a position of the photovoltaic material from which the photoelectrons are emitted, and the probe laser further comprises multiple probe lasers, one each of the multiple probe lasers dedicated to simultaneous irradiation of the photovoltaic material through an associated section of the transparent conductive material.
According to yet another aspect of the invention there is described a method of inspecting continuously moving photovoltaic material for electrical anomalies without stopping the movement or removing samples, by forming electrical connections to the photovoltaic material, and inducing either via electron beam or light beam a first localized current in the photovoltaic material with a first stripe source, sensing the first localized current at a first time, and likewise inducing a second localized current either via electron or light beam on the photovoltaic material with a second stripe source, sensing the second localized current at a second time, where the first stripe source is positioned downstream along the moving photovoltaic material from the second stripe source, and the first stripe source and the second stripe source are oriented at a non-zero angle relative to one another, analyzing properties of the first and second localized currents to detect the electrical anomalies in the photovoltaic material, and determining positions of the electrical anomalies in the photovoltaic material based at least in part on a time difference between the first time and the second time and a measure of the non zero angle between the first and second stripe sources.
BRIEF DESCRIPTION OF THE DRAWINGS
Further advantages of the invention are apparent by reference to the detailed description when considered in conjunction with the figures, which are not to scale so as to more clearly show the details, wherein like reference numbers indicate like elements throughout the several views, and wherein:
FIG. 1 is a first embodiment for a non-physical method for making electrical contact with a film, according to the present invention.
FIG. 2 is a first embodiment for illuminating a film, according to the present invention.
FIG. 3 is a second embodiment for illuminating a film, according to the present invention.
FIG. 4 is a third embodiment for illuminating a film, according to the present invention.
FIG. 5 depicts an embodiment for the flow of electrons through a first type of photovoltaic material in both the presence of a shunt and in normal operation of the photovoltaic material, when a probe and pump are applied to the material.
FIG. 6 depicts an embodiment for the flow of electrons through a second type of photovoltaic material in both the presence of a shunt and in normal operation of the photovoltaic material, when a probe and pump are applied to the material.
DETAILED DESCRIPTION
According to the several embodiments of the present invention, there is described a system 10 to perform an inline inspection for electrical defects of various kinds in a photovoltaic thin film 12 , as depicted in FIG. 1 . The photovoltaic 12 could be one or more of a variety of different kinds, such as Cu(In,Ga)Se, Cu(In,Ga)S, or any member of this family of chalcopyrites, or CdS, CdSe, CdTe, or any member of this family of materials, or amorphous silicon.
In one embodiment, the inspection is performed using a beam 14 , which is either an optical beam (optical beam induced current) or, if the material 12 is under vacuum, and electron beam (electron beam induced current). Regardless of the type of beam 14 used, the beam 14 induces a current in the photovoltaic 12 .
If the material 12 is moving, as in the case of film deposition on a moving web of material during manufacture, the beam 14 is preferably rastered back and forth across the material 12 , normal to the direction of movement of the material 12 , to produce an x, y scan 16 of the surface of the material 12 , where x is in the direction of the motion of the material 12 . This movement of the beam 14 can be accomplished by moving either the beam 14 source, or directing the beam 14 itself back and forth, such as by a moving minor for optical beam induced current or by a changing magnetic or electrical field for electron beam induced current. Alternately, the photovoltaic material 12 could be moved relative to the beam 14 .
Alternately, the beam 14 remains stationary relative to the width of the moving material 12 , so as to sample a single strip along the length of the material 12 , and the data collected is used for feedback to the film deposition processes. However, this embodiment does not allow for repair of the material 12 by laser ablation, as described hereafter. In yet another embodiment, multiple beams 14 could be used to sample multiple strips along the length of the material 12 .
The top conductor illuminated by the beam 14 is, in one embodiment, the transparent conducting oxide that is typically formed on a photovoltaic device, such as zinc oxide or indium tin oxide. The opposite side of the material 12 would then be the conducting substrate, such as stainless steel. The variation in the current produced by the photovoltaic 12 as induced by the beam 14 is used to detect electrical non uniformities in the film 12 as a function of position.
Electrical contacts 18 or 22 are preferably made between an ammeter 20 or other current sensing instrumentation and both sides of the photovoltaic 12 to detect the current that is induced by the beam 14 . The electrical contacts 18 and 22 can be made using either a method that does not physically contact the material 12 , or one that does physically contact the material 12 , or a blend of both methods.
For example, one method of making physical contact with a moving web of material 12 is by using conducting brushes 18 a that drag on the surfaces of the material 12 as the material 12 moves relative to the brushes 18 a. Another method is to use a conductive roller 18 b. Yet another method is to have a conductive physical probe 18 c that moves with the material 12 for a period of time, is then raised, repositioned, and lowered again to make contact in a different position of the material 12 .
When electron beam induced current is used, the electron beam 14 itself may be used as a non-contact upper electrical connection, forming either a positive or negative contact depending on the landing energy employed. If desired, two or more electron beams could be used, one for probing the material, and the second for making positive or negative electrical contact. In this embodiment, one or more of the physical contact methods 18 could be used for the electrical connection to the bottom of the material 12 , or some non-contact method could be used.
An alternate method for making electrical contact without physically touching the film 12 is to use a contained plasma or corona 22 . In this case, the film 12 passes by a relatively thin plasma or corona region, which is preferably isolated from the rest of the environment, whether that be a vacuum chamber or open atmosphere. This region can be confined such as with a rectangular box 22 running across the length of the material 12 , containing the necessary field for plasma or corona generation, and having a pressure that is different from the rest of the inspection device 10 .
Optical beam induced current can be performed on a moving film of material with one or two light beams 14 a and 14 b, as depicted in FIG. 2 . In one embodiment, these beams 14 a and 14 b run across the material 12 in opposite diagonal orientations, allowing for localization of any defect. The beams 14 a and 14 b are modulated in one embodiment, to gain additional information from the measurement. FIG. 2 depicts an embodiment where light beams 14 a and 14 b simultaneously illuminate a large swath of the material 12 . Defects are imaged along the moving axis of the material 12 , and localized on the material 12 due to the different orientations of the two beams 14 a and 14 b. This method tends to be faster than scanning each beam 14 a and 14 b as a point across the width of the material 12 . Scattered light from beams 14 a and 14 b could also be used to detect non-electrical defects during any point of the film deposition process, including defects on the bare substrate.
The time difference between anomalies as produced by the two beams 14 a and 14 b as the material 12 proceeds along its path of motion indicates where across the width of the material 12 the defect resides. For example, a defect in the material 12 that is located at a point in the material 12 where the beams 14 a and 14 b are relatively close to one another would produce electrical events that are relatively closer together in time, while a defect in the material 12 that is located at a point in the material 12 where the beams 14 a and 14 b are relatively far apart would produce electrical events that are relatively farther apart in time. With knowledge of the angle between the beams 14 a and 14 b and the speed of the material 12 , the location of the anomaly in the material 12 can be determined.
Electrical isolation of the inspected region can be provided by scribing away a line of the transparent conducting oxide contact to effectively segment the material 12 into electrically isolated regions. Alternately, it may be possible to rely on the sheet resistance of the transparent conducting oxide. The sheet resistance is typically about ten ohms per square, but in one embodiment, a very thin layer with a much higher sheet resistance is formed, as in the deposition of a zinc oxide film on Cu(In,Ga)Se material, then the inspection is performed, and finally the remainder of the transparent conducting oxide is formed, as in the deposition of a final aluminum doped film of zinc oxide.
Finding electrical defects while keeping up with the speed of a moving web of material 12 is best performed using relatively high data acquisition rates. A high speed time delay and integration acquisition system is used in one embodiment to acquire the induced current data. Analysis of the data may require a measurement of the current-voltage curve at each scan point. Weak diode or shunting defects are localized in one embodiment to within an area of about two millimeters in diameter and then electrically isolated from the remainder of the surface by laser ablation. In one embodiment the beam 14 sources preferably illuminate the web 12 between two parallel strip conducting brushes 18 , not depicted in FIG. 2 .
Some embodiments of the invention are especially beneficial for finding Ohmic shunts in the material 12 , which drain photocurrent from the load under any voltage bias, and also for finding weak diodes in the material 12 , which drain photocurrent from the load while under forward bias. Locating the positions of the worst shunts (the word “shunts” generally includes the concept of “weak diodes” as used hereafter) during the fabrication process allows them to be electrically isolated, which increases the efficiency of the photovoltaic material 12 . The electrical isolation of the shunts can be accomplished by laser ablation, for example, to remove the transparent conducting oxide layer or back contact material in a ring enclosing the shunt or, for the case of shunts located close to the edge of the photovoltaic material, by enclosing the shunt using both the edge of the photovoltaic material and an ablated region that intersects the edge of the material on either side of the shunt. The shunt position, and other useful information such as shunt resistance, as well as information on position and energy level of any recombination centers, and local characterization of areas of reduced carrier mobility can also be used to provide feedback for material deposition and general process control during fabrication of the photovoltaic 12 .
An optical beam 14 induced current scan of the film 12 that is performed after the final transparent conductive oxide contact is applied to the film 12 is generally sensitive to substantially all shunts beneath the conducting contact, not only the shunt closest to the light beam 14 . This greatly reduces the signal to noise level of the measurement. However, various embodiments of the present invention detect localized shunting defects in thin films 12 by measuring the photoelectric yield from the surface of the photovoltaic 12 before application of the final contact layer by using an ultraviolet laser 14 c, as depicted in FIG. 3 . This ultraviolet laser is called the probe laser 14 c. The scan of the photovoltaic material 12 by the probe laser 14 c may be assisted by simultaneous illumination of the probed region with a visible laser, called the pump laser 14 d.
The ultraviolet laser 14 c in one embodiment is held at a high enough energy to excite electrons from the conduction band minimum to the vacuum, but at an energy that is too low to excite electrons from the top of the valence band maximum to the vacuum. The pump laser 14 d in this embodiment is held at a high enough energy to excite electrons from the valence band to the conduction band, but at an energy that is too low to excite electrons from the conduction band to the vacuum.
In one embodiment, the probe laser 14 c is a 266 nanometer, 4.66 electron Volt, frequency quadrupled YAG laser, and the pump laser 14 d is a 532 nanometer, 2.33 electron Volt, frequency doubled YAG laser. The intensity of the pump laser 14 d is much greater than the intensity of the probe laser 14 c in this embodiment, so that most of the photoelectrons are excited to the conduction band by the pump laser 14 d rather than by the probe laser 14 c.
This method could be applied, by way of example, to a thin (four micron) film of CdTe deposited on glass—a typical superstrate configuration CdTe solar cell—just before deposition of the final conducting film as a back contact. The ultraviolet probe laser 14 c scans the CdTe surface 12 in a dark room. It incites the ejection of photoelectrons from the top five to ten nanometers of the CdTe material 12 . Because the energy of the probe laser 14 c is not high enough to excite electrons from the valence band at 5.78 electron Volts, only the electrons that are initially excited by the probe 14 c from the valence band to states in the conduction band at 4.28 electron Volts are ejected as photoelectrons. For sufficiently low intensities of the probe laser 14 c, the count rate for these photoelectrons is relatively small.
A large population of electrons may be excited to the CdTe conduction band by intense illumination of the film 12 from the opposite side (through the glass substrate) by the visible light pump laser 14 d. These electrons are excited throughout the depth of the film 12 , but relatively few photons reach the top few nanometers of the CdTe 12 surface on the opposite side from the glass substrate because of the high absorption of visible light by CdTe. Electrons in the conduction band reach the ultraviolet probe 14 c primarily by conduction across the CdTe film 12 . In general, the action of the solar cell 12 in the presence of visible light (such as from the pump laser 14 d ) conducts the electrons away from the ultraviolet probe 14 c and towards the glass (on the bottom of the material 12 ). However, in the presence of a shunt, the electrons conduct in the opposite direction, towards the ultraviolet probe 14 c, where some are ejected as photoelectrons, and thereby serve to complete a circuit through an ammeter (not depicted in FIG. 3 ) that is connected to the detector. Hence, an elevated ammeter reading during the scan indicates the presence of a shunt in the photovoltaic film 12 . FIG. 5 depicts both the flow of electrons in the presence of a shunt, and in normal operation of the photovoltaic 12 .
Because the back contact of the film 12 has not yet been deposited on the CdTe surface, the shunts are generally electrically isolated from one another by the high resistivity of the CdTe film 12 , so that the probe 14 c is only sensitive to electrical defects directly beneath it. The visible light 14 d, besides pumping electrons to the conduction band and turning on the open circuit voltage of the solar cell 12 , also serves to induce a forward bias, and thereby turns on any weak diodes beneath the probe laser 14 c by means of the open circuit voltage developed across the film 12 in the vicinity of the probe 14 c during illumination.
For the case of a Cu(In,Ga)Se solar cell 12 , the inspection procedure is different because the Cu(In,Ga)Se solar cell 12 is grown in a substrate configuration beginning with the opaque back contact. In one embodiment of an inspection process for a Cu(In,Ga)Se solar cell 12 , both the probe laser 14 c and the pump laser 14 d are directed to the CdS surface opposite the substrate, as depicted in FIG. 4 . The CdS film 12 is typically a fifty to one hundred nanometer thick layer deposited on top of the active Cu(In,Ga)Se film, and serves to complete the junction for the solar cell 12 . Substantially all of the photoelectrons ejected by the ultraviolet probe 14 c are ejected from the CdS film 12 . The band gap of CdS is 2.4 electron volts, which exceeds the 2.33 electron volt energy of the pump laser 14 d. Hence, electrons are only significantly pumped in the Cu(In,Ga)Se material beneath the CdS film, and predominantly conduct vertically through the film 12 to the CdS surface before being excited by the ultraviolet probe 14 c. FIG. 6 depicts both the flow of electrons in the presence of a shunt, and in normal operation of the film 12 .
In general, the action of the solar cell 12 conducts electrons to the ultraviolet probe 14 c, such that the photoelectron signal remains high. However, in the presence of a shunt the pumped electrons are conducted in the opposite direction, such that the photoelectron signal is small. Hence, a Cu(In,Ga)Se shunt is detected by a decrease in the signal—opposite that of the case for CdTe, where a shunt is detected by an increase in the signal.
As for the CdTe case, the inspection is predominantly sensitive to shunts beneath the probe laser 14 c, due to the high resistivity of the CdS film 12 . The inspection is preferably performed under vacuum, to allow the photoelectrons to reach the detector. For the cases described above, the pump laser may be replaced by any source of light, such as a broad spectrum lamp, that excites electrons between the valence and conduction bands but does not have the energy to excite electrons from the conduction band to the vacuum. This could be referred to as a lower energy light source, not necessarily in the visible range of the spectrum. The intensity of this light source may be adjusted to vary the open circuit voltage across the photovoltaic film 12 , thereby allowing the inspection to selectively activate weak diodes that have different open circuit voltages. Likewise, the probe laser may be replaced by any light source, including a broad spectrum lamp, with an energy sufficient to excite electrons from the conduction band minimum to the vacuum. This could be referred to as a higher energy light source.
A vacuum of about one-tenth of a millitorr to about one millitorr is created in a chamber mounted to a frictionless air bearing that is passed over the film 12 . Alternately, the film 12 is passed beneath a vacuum chamber mounted to a frictionless air bearing, such as in the case of a moving conducting web on which a Cu(In,Ga)Se film is deposited. Either the probe laser 14 c or both the probe and pump lasers 14 c and 14 d are directed through an ultraviolet quality fused silica window 24 that is coated with a transparent conducting oxide film on the surface that faces the photovoltaic material 12 . The separation between the window 24 and the photovoltaic film 12 is reduced to a small enough gap (such as less than about one millimeter) to allow ejected photoelectrons from the photovoltaic film 12 to reach the transparent conducting oxide film, and from there to be conducted to an ammeter (not depicted in FIG. 4 ).
The opposite terminal of the ammeter is electrically connected to the single conducting contact on the solar cell 12 . For CdTe photovoltaics 12 , the conductor is the transparent conducting oxide layer that is deposited on the glass substrate. For Cu(In,Ga)Se photovoltaics 12 , the conductor is typically the steel substrate on which the Cu(In,Ga)Se is grown. Electrical contact with the substrate can be made in a variety of different ways, such as with a conducting brush in the case of a moving web of material 12 .
In one embodiment of this invention, the transparent conducting oxide film coating the detector is scribed in the direction of the motion of the vacuum chamber or photovoltaic material to create separate detectors 28 that are read in parallel, as depicted in FIG. 4 . The ultraviolet probe 14 c and the visible pump 14 d are then focused to a streak source across the window 24 , normal to the scribe lines 26 , so that data is collected simultaneously from all of the detectors 28 .
Thus, use of surface contact methods that are not based on the photoelectric effect, such as by using a plasma or a brush or, in the case of electron beam induced current, the electron beam itself (as either a positive or negative contact, depending on the landing energy), can be used for direct, in-line inspection of the photovoltaic material using electron beam induced current or optical beam induced current to detect not only the areas of the shunts, but also regions of poor carrier collection due to a poorly formed p-n junction, high recombination, or low mobility. Results from this in-line inspection can be used for electrical isolation of the shunts, or feedback for control of the deposition processes or other process steps involved in the fabrication of the photovoltaic device.
If sufficient signal to noise levels are available, two streak sources and detectors can be deployed at, for example, nominal angles of positive forty-five degrees and negative forty-five degrees with respect to the axis normal to the direction of the moving photovoltaic material 12 . The position of the defect is then determined by the time of arrival of the signal at each source. Such a configuration can also be used with optical sources and segmented detectors to locate other defects besides electrical shunts. These defects include, for example, regions of poor carrier collection due to a poorly formed p-n junction, high recombination, or low mobility due to deviations from ideal stoichiometry or defects in the crystal structure or the size of the crystalline regions, or the presence of contaminants. In addition, the bare substrate can be inspected for scratches or surface contamination (such as organic stains).
Yet another embodiment uses an electron source such as a scanning electron microscope column or nanotube emitter to complete the circuit. In one embodiment the electron source is rastered across the film in a direction normal to the direction of the moving material 12 . The signal is the electron beam induced current that is collected from the contact on the opposite side of the film 12 . The landing energy is preferably varied to deposit predominantly positive or negative charge, thereby utilizing the electron beam to make electrical contact with the top surface of the photovoltaic device 12 .
The foregoing description of preferred embodiments for this 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. Obvious modifications or variations are possible in light of the above teachings. The embodiments are chosen and described in an effort to provide the best illustrations of the principles of the invention and its practical application, and to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.
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A method of inline inspection of photovoltaic material for electrical anomalies. A first electrical connection is formed to a first surface of the photovoltaic material, and a second electrical connection is formed to an opposing second surface of the photovoltaic material. A localized current is induced in the photovoltaic material and properties of the localized current in the photovoltaic material are sensed using the first and second electrical connections. The properties of the sensed localized current are analyzed to detect the electrical anomalies in the photovoltaic material.
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FIELD OF THE INVENTION
[0001] The invention is in the field of processing signals in hearing instruments. It especially relates to methods and devices for own voice separation, own voice shaping, and/or occlusion effect minimization.
BACKGROUND OF THE INVENTION
[0002] An important issue in signal processing in hearing instruments is perception of the own voice by a hearing instrument user.
[0003] The own voice reaches the tympanic membrane via two different paths:
Air conduction: the main contribution as long as the ear canal is not occluded Bone conduction: a significant contribution as soon as the ear canal is at least partially occluded.
[0006] These two contributions undergo an acoustic summation in the ear canal before being perceived.
[0007] The naturalness and pleasantness of this perception among others may depend on three distinct aspects:
Occlusion (increased low-frequency contents of the bone conducted portions of the own voice) Ampclusion (increased low-frequency contents of the hearing instrument sound, including the air-conducted portion of the own voice); Individual preferences (users might have gotten used to an ‘unnatural’ (influenced by their hearing capabilities) perception of the own voice or prefer their own voice to sound differently, for example less squeaky, from what would be ‘natural’).
[0011] In traditional hearing instruments, only the air conducted portion of the own voice can be affected by the processing (i.e. ultimately the frequency dependent amplification). A hearing instrument featuring active occlusion control can additionally affect—i.e. frequency-dependently decrease—the bone-conducted portion.
[0012] Even if the occlusion—especially the unwanted increase of low-frequency contents of the bone-conducted portion of the own voice—is fully removed by the active occlusion control, there is still a trade-off in terms of ampclusion. Specifically, the optimal setting of the hearing instrument gain in terms of ambient sounds might not be optimal in terms of the own voice.
[0013] In order to solve this problem, the state of the art proposes to detect own voice activity and to then, during own voice activity, temporarily change the hearing instrument settings so that they are optimal for the perception of the own voice.
[0014] WO 2004/021740 discloses such an example where an ear canal microphone is used to detect conditions leading to occlusion problems. EP 2 040 490 discloses approaches to detect ampclusion effect situations by a MEMS sensor. In order to account for the ampclusion effect and also for individual preferences, WO 03/032681 discloses to hold a training session in which the user may adjust parameters until the processed own voice is perceived as having a satisfying sound quality. The parameter values are stored and used when the own voice is detected.
[0015] However, the temporal change in the hearing instruments settings implies that the perception of ambient sounds is different while the user speaks than when he is quiet.
[0016] The state of the art does not propose any solution to this problem.
SUMMARY OF THE INVENTION
[0017] It is an object of the invention to provide approaches overcoming drawbacks of prior art approaches and especially to provide a method and a hearing instrument that make possible to shape the own voice in a manner pleasant for the user also in closed fitting set-ups.
[0018] This object is achieved by the method and the hearing instrument as defined in the claims.
[0019] A method of processing a signal in a hearing instrument with at least one outer microphone oriented towards the environment, an ear canal microphone oriented towards the user's ear canal, and at least one receiver capable of producing an acoustic signal in the ear canal comprises the steps of:
Processing a first signal from the outer microphone and a second signal from the inner microphone to yield an ambient sound portion signal estimate and an own voice sound portion signal estimate; Processing the ambient sound portion signal estimate into a processed ambient sound portion signal; Processing the own voice sound portion signal estimate into a processed own voice sound portion signal; Adding the processed ambient sound portion signal and the processed own voice portion signal for obtaining the acoustic signal in the ear canal.
[0024] In this, the adding may comprise adding the processed ambient sound portion signal and the processed own voice portion signal for obtaining an input for the at least one receiver. Alternatively, if two separate receivers for the respective processed signals are used, the adding may be an acoustical adding.
[0025] In the former case, the added signal obtained from adding the processed ambient sound portion and own voice portion signals may directly constitute the receiver signal (i.e. the signal fed to the receiver under Digital-to-analog conversion) or may be further processed prior to being fed to the receiver, for example by a possibly situation dependent amplification characteristics.
[0026] The acoustic signals incident on the outer microphone and on the inner microphone each comprise a mixture of signal portions coming from ambient sound—influenced, by the presence of the person and of the hearing instrument—and signal portions coming from the own voice—also influenced by the presence of the person and of the hearing instrument.
[0027] It is a first insight of the invention that because on the paths to the outer and inner microphone(s), respectively, the signal portions are influenced in different manners, and that this makes a separation of the signal portions possible.
[0028] It is a second insight of the invention that the signal portions (estimates for the ambient sound portion and own voice portion of the outer microphone signal) can be processed differently and simultaneously to yield, after summation, a receiver signal.
[0029] For estimating the ambient sound signal portion and the own voice portion, different approaches may be used.
[0030] Especially, in accordance with a first possibility, statistical signal separation techniques can be used. Such methods may be without the aid of information on the source signal properties and signal paths, or they may use the aid of such information. Such statistical methods base on the assumption that the ambient sound portion and the own voice portion are statistically independent. An example of a statistical method is blind source separation.
[0031] In accordance with a second possibility, signal processing is carried out based on pre-defined processing steps processing the signals from the inner microphone and from the outer microphone into an ambient sound signal portion and a own voice signal portion.
[0032] In accordance with a group of examples, an estimate of the own voice signal portion is obtained and subtracted from the (optionally pre-processed) outer microphone signal to yield the ambient sound signal portion. In this group of embodiments, the processing of the outer microphone signal into a receiver signal comprises the steps of subtracting an estimate of an own voice signal to yield an estimate of the ambient sound signal portion, processing the ambient sound portion signal estimate, processing the own voice portion signal estimate, and adding the processed ambient and own voice portion signals to yield an added signal that serves, unprocessed or further processed—as the receiver signal.
[0033] The own voice signal portion may be obtained, (for example, if no relevant direct sound component is present/to be expected), by subtracting the receiver signal from the inner microphone signal.
[0034] In this, two corrections can be made:
A first correction may account for the receiver response, the inner microphone response, and (as inherent part of the receiver-to-microphone transfer function), the influence of the signal path from the receiver to the inner microphone. For this first correction, a transfer function, especially a filter function may be applied to the receiver signal before the latter is subtracted from the inner microphone signal. The first correction is applied on the receiver signal prior to its subtraction from the inner microphone signal. What results is an estimate of the own voice portion of the inner microphone signal. The first correction may also be viewed as determining an estimate of a receiver generated inner microphone signal portion rRM and subtracting the same from the inner microphone signal. A second correction accounts for the difference between the signal paths from the source of the own voice (vocal cords, resonating elements) to the inner microphone on the one hand and to the outer microphone on the other hand, as well as, (potentially negligible) the difference between the inner microphone response and the outer microphone response. The second correction is applied to the own voice portion of the inner microphone signal prior to its subtraction from the outer microphone signal. The second correction may be viewed as estimating from the own voice portion of the inner microphone signal, an own voice portion of the outer microphone signal. This may for example be done by a function, such as a filter, that takes into account the differences of the sound paths from own voice generation (vocal cords, resonating bodies etc.) to the inner and to the outer microphone respectively. This function (filter or the like) may also take into account different characteristics of the inner and outer microphones if such differences are relevant. The own voice portion of the outer microphone signal may be subtracted from the outer microphone signal to yield the ambient sound portion of the outer microphone signal.
[0040] Especially in open fitting set-ups a third correction may be advantageous which accounts for the direct sound incident on the inner microphone, which is often expressed in terms of the Real Ear Occluded Gain (REOG). This third correction may especially be advantageous if direct sound portions of ambient sound are not negligible, such as in open fitting set-ups, if a vent has a comparably large diameter or is comparably short, etc. The third correction is applied to the inner microphone signal after subtraction of the receiver generated portion.
[0041] Such estimate of the direct sound portion of ambient sound may for example be obtained from applying a value for the REOG on the outer microphone signal (if necessary and applicable corrected for different microphone characteristics).
[0042] The ambient sound portion of the outer microphone signal and the own voice portion of the outer microphone signal are then processed differently on the different paths.
[0043] Implemented in the hearing instrument, a filter making the first correction (and/or a filter making a third correction, if applicable), may be considered to belong to the separator unit. Alternatively, it/they may also be seen as pre-conditioning filter(s) for the actual separator unit comprising the filter for the second correction.
[0044] For the first and/or second corrections and/or the third correction, an adaptive filter/adaptive filters may be used.
[0045] For the first correction, the corrected (filtered) receiver signal is such that all portions of the inner microphone signal that correlate with the receiver signal are subtracted from the inner microphone signal. What remains is the portions that do not correlate with the receiver signal, i.e. that are not caused by the receiver and are thus caused by the own voice (especially bone conducted portions), and, as the case may be, by direct sound. Therefore, the difference between the inner microphone signal and the filtered receiver signal may be used as the error signal input of the adaptive filter (or, to be precise, as an error signal input of an update algorithm of the adaptive filter). Corresponding filter update algorithms that minimize an error signal are known in the art, for example base on the so-called LMS (Least Mean Squares) or RLS (Recursive Least Squares).
[0046] For the second correction, the insight is used that that portion of the outer microphone signal which correlates with the own voice portion of the inner microphone signal is the own voice portion of the outer microphone signal. Therefore, the ambient sound signal portion that results after subtraction of the own voice portion may serve as an error signal to be minimized by the filter.
[0047] In a specific embodiment, the signal separation is based on two adaptive filters. The first filter (herein denoted as P-filter) accounting for the first correction allows to subtract the accordingly P-filtered receiver signal from the inner microphone signal resulting in an estimate ( ) of the own voice portion of the inner microphone signal. The second filter (herein denoted as H-filter) accounts for the second correction and allows to obtain the own voice portion of the outer microphone signal as the H-filtered own voice portion of the inner microphone signal.
[0048] Still further, in embodiments, if the direct sound portions of ambient sound are subtracted from the direct sound estimate, a static filter may be used to estimate the direct sound portions of ambient sound from the outer microphone signal. Alternatively, and adaptive filter may be used for this purpose.
[0049] The invention also concerns a hearing instrument equipped for carrying out the method according to any one of the embodiments described in the present text.
[0050] Especially, in accordance with an aspect of the invention, a hearing instrument comprising at least one outer microphone (a microphone oriented towards the environment, capable of converting an acoustic signal incident on the ear into an electrical signal) and at least one ear canal microphone (i.e. a microphone in acoustic communication/connection with the ear canal, capable of picking up noise signals from the volume between an earpiece of the hearing instrument and the tympanic membrane) is used. The ear canal microphone is also denoted “inner microphone” in this text. The hearing instrument comprises an own voice separator. The own voice separator separates, based on signals from the outer microphone(s) and the inner microphone(s), the signal from the outer microphone(s) into an ambient sound portion and an own voice portion. The hearing instrument comprises two separate signal processing paths set up in parallel, one for ambient sounds, and the other one for the own voice processing. The signals on the two signal paths are processed differently and simultaneously, for example by applying different frequency dependent amplification characteristics and/or by implementing a gain G v on a low latency path because the high latency of the hearing instrument is said to be perceived more disturbing for the own voice than for ambient sound. The processed signals on the two paths are summed to a receiver signal before fed to the hearing aid receiver(s).
[0051] The outer microphone or outer microphones can be placed, as is known for hearing instruments, in the ear, especially in the earpiece (in case of a Completely-in-the Canal-(CIC), in-the-canal- (ITC), or in-the-Ear- (ITE) hearing instrument) in acoustic communication/connection with the outside so as to predominantly pick up acoustic signals from the outside. The outer microphone(s) may also be placed in a behind-the-ear (BTE) component of the hearing instrument, or in a separate unit communicatively coupled to the rest of the hearing instrument.
[0052] A method of fitting a hearing instrument of the kind described herein may comprise fitting of the own voice processing on the corresponding path by means of voice samples. To this end, a user wearing the hearing instrument may be instructed to speak, especially in a quiet room. Depending on the user's perception of his own voice, the processing parameters of the own voice portion sound processing path may be adapted until the user is comfortable with the perception of her/his own voice. Once this has been achieved, the user will remain comfortable with the perceived own voice due to the approach of the invention, even in situations where in addition to the own voice the user hears other sound that is also processed for better audibility in the hearing instrument.
BRIEF DESCRIPTION OF THE DRAWINGS
[0053] Hereinafter, embodiments of methods and devices according to the present invention are described in more detail referring to Figures. In the drawings, same reference numbers, letters and symbols refer to same or analogous elements. The drawings are all schematical. The figures show:
[0054] FIG. 1 a simplified scheme of a hearing instrument with an earpiece inserted in an ear so that a remaining volume between the earpiece and the eardrum is defined;
[0055] FIG. 2 the concept of two different signal processing paths for the ambient sound and own voice sound;
[0056] FIG. 3 an embodiment with a signal separator comprising two filters;
[0057] FIG. 4 a variant of the embodiment of FIG. 3 , wherein the filters are adaptive filters;
[0058] FIG. 5 the situation in which the direct sound that gets directly to the inner microphone, for example through the vent etc. is also taken into account; and
[0059] FIG. 6 an embodiment with correction for direct sound.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0060] The hearing instrument schematically represented in FIG. 1 may be of the behind-the-ear (BTE) type (including for example RIC (receiver-in-the-canal)=CRT (canal-receiver-technology), of the in-the-ear (ITE) type, (of the completely-in-the-canal (CIC) type or other ITE type) or of any other type. It comprises an outer microphone 1 . In practice, often more than one outer microphones are used, and/or in addition to the outer microphone further receiving means for receiving signals may be present, such as a telecoil receiver, a receiving unit with an antenna for receiving wirelessly transmitted signals, etc. The (electrical) input signal obtained from the at least one outer microphone is processed by a signal processing unit 3 to obtain an output signal or receiver signal. The signal processing unit 3 depicted in FIG. 1 may comprise analog-to-digital conversion means and any other auxiliary means in addition to a digital signal processing stage. The signal processing unit may be physically integrated in a single element or may comprise different elements that may optionally be arranged at different places, including the possibility of having elements placed in an earpiece and other parts at an other place, for example in a behind-the-ear unit.
[0061] The receiver signal is converted into an acoustic output signal by at least one receiver (loudspeaker) 5 and is emitted into a remaining volume 8 between the user's eardrum 9 and the in-the-ear-canal-component of the hearing instrument. The hearing instrument further comprises an ear canal microphone 11 operable to convert an acoustic signal in the ear canal (in the remaining volume 8 in closed fitting setups) into an electrical signal supplied to the signal processing unit 3 .
[0062] The ear canal microphone 11 is part of the hearing instrument and present in the earpiece of the hearing instrument or possibly outside of the earpiece and connected to the earpiece by a tubing that opens out into the remaining volume 8 .
[0063] FIG. 2 depicts signal processing in embodiments of hearing instruments according to the invention. Ambient sound is incident on an outer microphone 1 . 1 (or on two outer microphones 1 . 1 , 1 . 2 , for example two omnidirectional microphones or an omnidirectional and a directional microphone etc.). The microphone signal or the microphone signals is/are analog-to-digital converted (Analog-to-Digital converter(s) ( 31 . 1 , 31 . 2 ) and then fed to a signal separator 32 .
[0064] For the discussion of the invention and its embodiments following hereinafter, for the sake of simplicity we only discuss processing the signals from one outer microphone. However, all embodiments of the invention are also suited for processing the input signals of more than one outer microphone.
[0065] The signal from the inner microphone 11 is—also after analog-to-digital-conversion 31 . 3 —also fed to the signal separator 32 .
[0066] By processing both, the signal from the outer microphone and from the inner microphone, the signal separator obtains an estimate for ambient sound that represents an ambient sound portion of the input signal and an estimate for bone conducted own voice sound signal that represents an own voice portion of the input signal.
[0067] The ambient sound portion and the own voice portion are processed on different signal processing paths by signal processing stages 41 , 42 on which they will typically be subject to a frequency dependent gain G, G v that is different for the ambient sound portion and for the own voice portion and that, in addition to the frequency, may depend on other parameters, such as settings chosen by the user, (for G) recognized background noise situations etc.
[0068] After the processing, the processed ambient sound portion and own voice portion signals are added to obtain a receiver signal r. The receiver signal is, under digital-to-analog conversion (in the digital-to-analog converter 33 ) fed to the receiver 5 .
[0069] The signal separator 32 does not need to be and in most cases will not be a separate physical entity but is part of the signal processing means of the hearing instrument; herein it is described as functionally separate processing stage.
[0070] In accordance with the above-discussed first possibility, statistical signal separation techniques can be used in the signal separator 32 . In accordance with a second possibility, a pre-defined signal processing topology is provided.
[0071] In accordance with the second possibility, signal processing is carried out based on pre-defined functions processing the signals from the inner microphone and from the outer microphone into an ambient sound signal portion and a own voice signal portion.
[0072] FIG. 3 depicts an example of processing an outer microphone signal and an inner microphone signal into a receiver signal r. From the outer microphone signal (transfer function/response of the outer microphone M 0 ), an estimate of the own voice portion is subtracted ( 51 ) to yield an estimate of the ambient sound signal before a frequency dependent gain G (that does not need to be constant and may depend on processing parameters and/or on individual user chosen settings) is applied to the latter. A different frequency dependent gain G v is applied to the own voice portion estimate , and the accordingly processed ambient sound and own voice signal portions are added ( 53 ) to yield the receiver signal r that is fed to the receiver 5 . R denotes the receiver response. The alternative gain model (or filter) G v can optionally be adjusted by the user according to his individual preferences, thus shaping his own voice without compromising the ambient sounds. The two signals components are summed to yield the receiver signal r before being fed to the receiver.
[0073] The receiver signal r is also filtered by a first filter P—with a filter function that is an estimate of RM, where M is the response of the inner microphone—and subtracted ( 55 ) from the signal picked up by the inner microphone 11 . This yields an estimate of the own voice portion of the inner microphone signal.
[0074] This signal is filtered by a second filter H yielding the estimate of the own voice portion of the outer microphone signal.
[0075] The second filter H has a filter function that is an estimate of H 1 /H 2 ·M 0 /M, where H 1 is the transfer function of the signal path from the voice source to the outer microphone and H 2 is the transfer function of the signal path from the voice source to the inner microphone.
[0076] In FIG. 3 , a denotes the ambient sound, v the own voice generated sound incident on the outer microphone, and v′ the own voice generated sound on the inner microphone.
[0077] This scheme is based on the assumption that the influence of the REOG is negligible. If the sound portion directly conducted to the inner microphone is to be taken into account, a further correction can be made, as explained further below.
[0078] The filter functions of the filters P, H can be determined based on at least one of
calculations experiments, data obtained during the fitting process, (especially for H) individual preferences expressed during the fitting process.
[0083] In an alternative embodiment, at least one of the filters P, H is not static but an adaptive filter. This is illustrated in FIG. 4 , showing an embodiment where both, the P filter and the H filter are adaptive filters. Only the differences to FIG. 3 are described.
[0084] In FIG. 4 , the P filter and the H filter are adaptive filters. The error signal of the P filter is the estimate of the own voice portion of the inner microphone signal, which should, as explained above, be minimized by the subtraction ( 55 ) of the filtered receiver signal from the inner microphone signal. The error signal for the H filter is constituted by the estimate a of the ambient portion of the outer microphone signal that should be minimized, i.e. reduced to the portion of the outer microphone which is uncorrelated with v′, by the subtraction of the filtered from the outer microphone signal.
[0085] The P-filter ideally converges towards =RM, wherein R is the frequency dependent receiver transfer function and M is the transfer function of the inner microphone. If the influence of the signal path S from the receiver to the inner microphone is not negligible, the P-filter ideally converges towards =RSM. The H-filter in this embodiment ideally converges towards =H 1 /H 2 ·M 0 /M where H 1 is the acoustic transfer function from the source of the own voice to the outer microphone and H 2 is the acoustic transfer function from the source of the own voice to the inner microphone.
[0086] FIG. 5 yet depicts the situation in which the direct sound that gets directly to the inner microphone, for example through the vent etc. is also taken into account. The sound x at the outer microphone is, like in the previously described embodiments, the sum of ambient sound a and of own voice v. The sound in the ear canal is the sum of the receiver generated sound signal rR, of the direct sound x′=x*REOG, and of the own voice portion v′=v*BC/AC=v*H 2 /H 1 , where BC denotes bone conduction and AC denotes air conduction (this is assuming that bone conduction from the own voice source to the outer microphone is negligible; in the notation of the previous figures the relation would be v′=v*H 2 /H 1 ).
[0087] The inner microphone signal is then M*(r*R+x′+v). After subtraction of the P-filtered receiver signal (P-filter 61 ) that has ideally the filter function P=RM the remaining signal is M*(x′+v′). A third filter 63 may be used to subtract the direct sound portion from this (subtraction 57 ); the third filter has ideally the filter function RO=REOG*M/M 0 , where REOG is the real ear occluded gain. What remains is v′*M, and this is filtered in the H-filter 62 to yield v*M 0 , which quantity, being the own voice portion of the outer microphone signal x*M 0 , is subtracted from x*M 0 to yield the ambient sound portion a*M 0 of the outer microphone signal.
[0088] The distinct processing paths for the ambient sound portion a*M 0 and the own voice portion v*M 0 of the outer microphone signal—via gain models G, G v —are analogous to the other embodiments described herein before.
[0089] FIG. 6 shows an implementation based on adaptive P, H, and RO filters , , and O taking into account the direct sound. The subtraction 55 of the P-filtered receiver signal from the outer microphone signal yields an estimate of the portions (x′+v′)*M of the inner microphone signal that are not caused by the receiver sound, and this estimate serves as the error signal for the P filter. An estimate of the direct sound portion of the inner microphone signal is obtained by applying the third filter (REOG filter; RO) 63 on the outer microphone signal. This estimate is subtracted from to yield the estimate of the own voice portion of the inner microphone signal, whereafter the latter is processed like in the embodiment of FIG. 4 . Ideally, the first, second and third filters 61 , 62 , 63 converge towards RM (or RSM), AC/BC*M 0 /M, and REOG*M/M 0 , respectively.
[0090] As an alternative, the estimate may be subtracted prior to the subtraction of the P-filtered receiver signal (exchange of 55 and 57 with respect to each other).
[0091] As other alternatives, one or more of the filters, for example the REOG filter 63 may be static while the other filter(s) are/is adaptive. Different combinations of adaptive and static filters may be used.
[0092] In the embodiments of FIGS. 3 and 4 , the filters P, H and the associated adders 51 , 55 may be viewed to constitute the signal separator; in FIG. 6 the signal separator additionally comprises the third filter RO and the corresponding adder 57 .
[0093] Various other embodiments may be envisaged. For example, prior to being fed to the receiver, the sum signal can be subject to further processing steps. Also, the outer microphone signal may, prior to being fed to the signal separator, subject to other processing steps.
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A method of processing a signal in a hearing instrument with at least one outer microphone oriented towards the environment, an ear canal microphone oriented towards the user's ear canal, and at least one receiver capable of producing an acoustic signal in the ear canal includes the steps of:
Processing a first signal from the outer microphone and a second signal from the inner microphone to yield an ambient sound portion signal estimate and an own voice sound portion signal estimate; Processing the ambient sound portion signal estimate into a processed ambient sound portion signal; Processing the own voice sound portion signal estimate into a processed own voice sound portion signal; and Adding the processed ambient sound portion signal and the processed own voice portion signal for obtaining an input for the receiver.
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BACKGROUND OF THE INVENTION
This invention relates generally to solenoid valves and, more particularly, to a pilot type solenoid valve for opening and closing a fluid pipe way.
The solenoid valve of the kind referred to can be effectively utilized in turning on and off supplied water in showering device and so on.
DESCRIPTION OF RELATED ART
As has been disclosed in, for example, U.S. Pat. No. 4,081,171 of Norman D. Morgan et al., known solenoid valve has a valve seat formed in a valve housing so as to define on both sides of the seat a fluid supply side and a fluid discharge side, a main valve member made integral with a diaphragm is disposed within the housing for an engagement with and disengagement from the valve seat, and a pressure chamber is defined within the housing to be above the main valve member, while this pressure chamber is made to communicate, through an orifice made through the main valve member, with the fluid supply side and, through a pilot passage also penetrating through the main valve member, with the water discharge side. Further, a solenoid means is mounted onto the valve housing to be positioned above the pressure chamber, and a pilot valve is mounted to a plunger of the solenoid means for opening and closing a pilot path, while a spring force of a resetting spring is applied to the plunger carrying the pilot valve.
Accordingly, the pilot valve is made to close the pilot path as biased by the spring force of the resetting spring when the solenoid means is in non-excited state, whereas the pilot valve is to open the pilot path with the plunger displaced in a direction separating from the pilot path against the biasing force of the resetting spring when the solenoid means is in excited state.
With the pilot valve actuated to close the pilot path by the biasing force of the resetting spring, the pressure chamber is made to be at the same pressure as the fluid supply side through the orifice of the main valve member, and the pilot valve can be reliably held in the closing state of the pilot path into which state an elasticity of the diaphragm is also acting. When, on the other hand, the pilot valve is actuated to open the pilot path with the solenoid excited, a fluid in the pressure chamber flow through the pilot path to the discharge side, the pressure in the pressure chamber is thereby caused to decrease, the main valve member is separated from the valve seat under the fluid pressure on the supply side, and the valve is put in an open state.
In this valve open state, a main stream of the fluid attained from the supply side to the discharge side is to flow through lower side of the main valve member in the open state, but part of the fluid takes a path of flowing from the orifice, through a zone adjacent the plunger and the pilot path, to the discharge side. Accordingly, the zone adjacent the plunger is always exposed to the flowing fluid, so that there will arise a problem that such impurity contained in the fluid as iron, calcium and the like components will accumulatively adhere to guide pipe or the like disposed adjacent the plunger and a smooth displacement of the plunger cannot be maintained.
In the known valve of the foregoing arrangement, further, the provision of the pilot path in the main valve member makes it necessary to arrange operating stroke of the plunger in correspondence with operating stroke of the main valve member, so that there arises another problem that a larger solenoid is called for and the entire body of the solenoid valve has to be enlarged.
SUMMARY OF THE INVENTION
Is is a main object of the present invention, therefore, to eliminate such problems as in the above, and to provide a solenoid valve which effectively prevents any impurities from accumulatively adhering to a portion adjacent the plunger in the solenoid and is thus highly reliable in the operation.
It is another object of the present invention to provide a solenoid valve which is capable of restraining the operating stroke of the plunger to be the minimum and thus to minimize in size the solenoid and eventually the entire body of the solenoid valve.
Other objects and advantages of the present invention shall be made clear in the following description of the invention detailed with reference to preferred embodiments shown in accompanying drawings.
BRIEF EXPLANATION OF THE DRAWINGS
FIG. 1 is a side view in an embodiment of the solenoid valve according to the present invention;
FIG. 2 is a plan view of the solenoid valve of FIG. 1;
FIG. 3 is a schematic sectioned view of the solenoid valve shown in FIG. 1;
FIGS. 4 through 6 are schematic sectioned views in other embodiments of the solenoid valve according to the present invention;
FIG. 5A is a more detailed view of FIG. 5 depicting the diaphragm valve in greater detail;
FIGS. 7 through 9 are schematic sectioned views in further embodiments of the solenoid valve employing a self-maintaining type solenoid in the solenoid valve according to the present invention;
FIG. 10 shows in a plan view another embodiment of the solenoid valve provided with a water supply side outlet according to the present invention;
FIG. 11 is a schematic sectioned view of the solenoid valve of FIG. 10; and
FIG. 12 shows in a plan view a state in which two of the solenoid valves shown in FIG. 10 are jointly coupled.
While the description of the invention is made with reference to the embodiments shown in the drawings, it should be appreciated that the intention is not to limit the invention only to these embodiments shown but rather to cover all modifications, alterations and equivalent arrangements possible within the scope of appended claims.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1-3, there is shown a solenoid valve 10 in an embodiment according to the present invention, which solenoid valve 10 comprises a valve housing 11 including therein a valve seat 12 and fluid supply and discharge sides or passages 13 and 14 defined on both sides of the valve seat 12, a fluid inlet port 15 connected to the fluid supply side 13 and a fluid discharge port 16 connected to the fluid discharge side 14. In the housing 11, further, a main valve member 17 is disposed to be engageable with and disengageable from the valve seat 12, and an elastic diaphragm 18 is provided integral with the main valve member 17 preferably by means of bonding along peripheral part of them. These main valve member 17 and diaphragm 18 made integral with each other are disposed so that a fluid pressure in the supply side 13 will be applied to the peripheral part, while a fluid pressure in the discharge side 14 will be applied to a central part of them.
A lid 19 forming part of the valve housing 11 is fitted above the main valve member 17 to define a first pressure chamber 20 above the member 17, and this first pressure chamber 20 is made to communicate with the fluid supply side 13 through an orifice path 21 made to penetrate through the main valve member 17 and diaphragm 18. On one side of the lid 19, a mounting part 22 is provided to project thereout, and a solenoid 23 is mounted onto this mounting part 22. This solenoid 23 comprises a coil 24, plunger 25 consisting of a rod-shaped piston and resetting spring 26 for the plunger, and its mounting to the mounting part 22 is carried out in liquid tight manner by screwing a threaded bottom end of solenoid housing into a threaded port 27 of the mounting part 22, with a diaphragm pilot valve 28 interposed centrally and an annular packing 29 interposed peripherally around the port 27.
In this case, a pilot chamber 30 is defined below the solenoid 23 by means of the diaphragm pilot valve 28, and this pilot chamber 30 is made to communicate, through a path 31 penetrating through the lid 19, with the first pressure chamber 20 and, through a path 32 made in the valve housing 11 and a packing 33 interposed between the housing 11 and the mounting part 22 for liquid tightness, with the fluid discharge side 14. Further, inside the solenoid 23, a second pressure chamber 34 is defined peripherally about the plunger 25 and above the diaphragm pilot valve 28, while this pilot valve 28 itself is joined to the plunger 25 for cooperation therewith so as to engage with and disengage from a pilot valve seat 35 disposed between the pilot chamber 30 and the path 32.
The operation of the foregoing solenoid valve 10 shall be referred to next. Now, in a normal state of the plunger 25 urged downward by the biasing force of the resetting spring 26 and, consequently, the diaphragm pilot valve 28 engages with the pilot valve seat 35, the first pressure chamber 20 communicates through the orifice path 21 with the fluid supply side 13 to have the same fluid pressure therewith, and the main valve member 17 is made to engage with the valve seat 12 under the elasticity of the diaphragm 18. That is, the solenoid valve 10 is in its closed state. Upon excitation of the coil 24 of the solenoid 23, the plunger 25 as well as the diaphragm pilot valve 28 are driven upward to be separated from the seat 35, the pilot valve comes in its open state to have a fluid pressure in the discharge side 14 applied to the first pressure chamber 20 through the path 32, valve seat 35, pilot chamber 30 and path 31, whereby the pressure in the first pressure chamber 20 is made lower than that in the supply side 13, the main valve member 17 is caused to disengage from the seat 12 by the pressure in the supply side 13 now higher, the main valve member 17 thus comes to its open state so that the fluid supply and discharge sides 13 and 14 are in direct communication with each other. That is, the solenoid valve 10 is in its open state.
In the foregoing open state of the solenoid valve 10, a direct fluid flow from the supply side 13 to the discharge side 14 is the main stream, whereas a partial stream of fluid is made to flow also from the supply side 13 to the discharge side 14 but through the orifice path 21, pilot chamber 30, pilot valve seat 35 and path 32. In this case, the diaphragm pilot valve 28 between the pilot chamber 30 and the second pressure chamber 34 defined inside the solenoid 23 is disposed liquid tight, so that any fluid from the supply side 13 to the discharge side 14 can be prevented from entering into the space peripherally about the plunger 25. Therefore, it is possible to prevent any impurity in the fluid from accumulatively adhering to the plunger 25 in the solenoid 23 and its neighboring parts, the operation of the plunger 25 and eventually the opening and closing operation of the solenoid valve 10 can be well assured for a long term, and the durability of the valve 10 can be remarkably improved. In addition, the pilot chamber 30 is remarkably smaller in the depth than that of the first pressure chamber 20, the pilot valve 28 can be made to be of a remarkably smaller operating stroke, and the plunger 25 and eventually the entire solenoid 23 for actuating the pilot valve 28 can be sufficiently minimized in size, as will be readily appreciated.
Referring next to FIG. 4, there is shown another embodiment of the solenoid valve according to the present invention, in which embodiment the solenoid valve 10A is provided with an intake path 36 made in the top portion of the solenoid 23 for communicating the second pressure chamber 34 with the atmosphere. With this arrangement, the second pressure chamber 34 is maintained at the atmosphere level, with the atmosphere always led into the chamber through the path 36, a backpressure acting on the diaphragm pilot valve 28 is made constant, and a force required for displacing the plunger 25 with respect to the pilot valve seat 35 can be made smaller. Accordingly, the entire size of the solenoid 23 can be further minimized. In this embodiment of FIG. 4, other constituents and their function are the same as those in the embodiment of FIGS. 1-3, and the same reference numerals as those in FIGS. 1-3 are likewise used in FIG. 4 for the same constituents.
Referring to FIG. 5, there is shown a further embodiment of the solenoid valve 10B according to the present invention, in which the path 32 communicating the pilot chamber 30 with the discharge side 14 is made to communicate, through a further pressure leading path 37, with the second pressure chamber 34, and the pilot valve seat 35 is made to be engaged and disengaged by the diaphragm pilot valve 28 on the side of the path 31 communicating the first pressure chamber 20 with the pilot chamber 30. According to this arrangement, the same pressure is achieved in the pilot chamber 30 and the second pressure chamber 34 on both sides of the diaphragm pilot valve 28, so that this valve 28 can be freed from any additional load, the required force for driving the pilot valve 28 and plunger 25 can be minimized, and the arrangement can be sufficiently contributive to the minimization in size of the solenoid. In the present instance, further, the fluid from the supply side 13 to the discharge side 14 is partly caused to enter into the second pressure chamber 34, but such partly entering fluid is limited to be of a slight amount corresponding to a relatively small displacement of the diaphragm pilot valve 28, and the adhering of any impurity to the plunger 25 and its neighboring members is out of question. In the present instance, too, other constituents and their function are the same as those in the embodiment of FIGS. 1-3, and the same reference numerals as those in FIGS. 1-3 are likewise used in FIG. 5 for the same constituents.
Referring to FIG. 6, there is shown another embodiment of the solenoid valve 10C according to the present invention, in which the second pressure chamber 34 is made to communicate with the first pressure chamber 20 through a pressure leading path 38. With this arrangement, the same pressure is attained at the first and second pressure chambers 20 and 34, so that no additional load is applicable to the pilot valve 28, the required force for driving the pilot valve 28 and plunger 25 can be made smaller similarly to the embodiment of FIG. 5, and the solenoid can be sufficiently minimized in size. In the present instance, too, the fluid from the supply side 13 to the discharge side 14 is partly caused to enter into the second pressure chamber 34, but this partially entering fluid is limited to be of a slight amount corresponding to the relatively small displacement of the diaphragm pilot valve 28, and the adhering of impurity to the plunger 25 and its neighboring members is also out of question. In the present instance, other constituents and their function are the same as those in the embodiment of FIGS. 1-3, and the same reference numerals as in FIGS. 1-3 are likewise used in FIG. 6 for the same constituents.
According to another feature of the present invention, the solenoid is formed in a self-maintaining type. That is, as shown in FIG. 7, the solenoid valve 10D in this embodiment comprises a permanent magnet 39 and a core 40 disposed above the resetting spring 26 to be magnetized by the magnet 39. When a current is fed to the coil 24D of the solenoid 23 in a direction of separating the plunger 25 from the pilot valve seat 35, the plunger 25 is moved upward in the drawing and is then attracted at its upper end by the magnetized core 40, the plunger 25 is thus maintained at its position separated from the pilot valve seat 35 against the biasing force of the resetting spring 26, and the diaphragm pilot valve 28 joined to the plunger 25 is maintained in the open state. When, on the other hand, a current in a direction of cancelling the attractive force of the core 40 is supplied to the coil 24D of the solenoid 23, the plunger 25 is caused to be displaced toward the pilot valve seat 35 by the biasing force of the resetting spring 26, and the diaphragm pilot valve 28 is placed in the closed state. Therefore, the solenoid is to self-maintain either the opened or closed state with the attraction of the core 40 or the biasing force of the resetting spring 26 even when the current supply to the coil 24D of the solenoid 23 is turned off, so long as the diaphragm pilot valve 28 is either in the opened or closed state. In the present instance, other constituents and their function are the same as those in the embodiment of FIGS. 1-3, and the same reference numerals as those in FIGS. 1-3 are likewise used in FIG. 7 for the same constituents.
In another embodiment of the present invention as shown in FIG. 8, the permanent magnet 39 and thereby magnetized core 40 are incorporated in the foregoing embodiment of FIG. 5 to form the solenoid valve 10E. In the present instance, similarly to the embodiment of FIG. 5, the second pressure chamber 34 is made to communicate with the discharge side 14 through the pressure leading path 37 so that the same fluid pressure will be achieved at both of the second pressure chamber 34 and pilot chamber 30, required driving force for the pilot valve 28 and plunger 25 can be made smaller, and the solenoid 23 and eventually the solenoid valve 10E can be minimized in size. Similarly to the case of FIG. 7, the plunger 25 is driven in response to the direction of the current supplied to the coil 24E in the solenoid 23, and either the opened or closed state of the solenoid is to be self-maintained by means of the attraction of the core 40 or the biasing force of the resetting spring 26. In the present embodiment, other constituents and their function are the same as those in the respective embodiments of FIGS. 1-3, 5 and 7, and the same reference numerals as those in these embodiments are likewise employed in FIG. 8 for the same constituents.
In a further embodiment of the present invention as shown in FIG. 9, the solenoid valve 10F is formed by incorporating the permanent magnet 39 and thereby magnetized core 40 in the embodiment of FIG. 6. In the present instance, similarly to the case of FIG. 6, the second pressure chamber 34 is made to communicate through the pressure leading path 38 with the first pressure chamber 20 which communicate with the fluid supply side 13, and the same pressure is made achievable at both of the second pressure chamber 34 and the pilot chamber 30 communicating with the first pressure chamber 20, whereby the required driving force for the pilot valve 28 and plunger 25 can be made smaller enough for minimizing in size the solenoid 23 and eventually the solenoid valve 10E. Also in the same manner as in the embodiment of FIG. 7, it is possible to drive the plunger 25 in response to the direction of the current supplied, so as to allow either the opened state or closed state of the solenoid to be self-maintained by means of the attraction of the core 40 or the biasing force of the resetting spring 26. In the present embodiment, other constituents and their function are the same as those in the respective embodiments of FIGS. 1-3, 6 and 7, and the same reference numerals as those in these embodiments are likewise employed in FIG. 9 for the same constituents.
Referring to FIGS. 10 and 11 showing another embodiment of the solenoid valve 10G according to the present invention, this valve 10G is provided on the fluid supply side 13 but at a position opposite to the fluid inlet port 15 with a supplied fluid outlet 41 communicating directly with the inlet port 15 internally, while other constituents of the solenoid vale 10G are substantially the same as those in the self-maintaining type solenoid valve 10D of FIG. 7. An O-ring 42 is mounted around the outlet 41, for liquid tight connection to another solenoid valve at its inlet port 15. It will be appreciated that, with this arrangement, a plurality of the solenoid valves 10G can be arranged as mutually connected with the inlet port 15 of each solenoid valve coupled to the outlet 41 of another solenoid valve.
In FIG. 12, there is shown an aspect in which two of the solenoid valves 10G and 10G1 of the above embodiment of FIGS. 10 and 11 are connected to each other, in which the solenoid valves 10G and 10G1 are mounted onto an optimum mounting plate 43 while coupling the supplied fluid outlet 41 of one solenoid valve 10G into the inlet port 15 of the other solenoid valve 10G1, whereby the fluid supply sides of the two valves are interconnected in series. To the inlet port 15 of the one solenoid valve 10G, a connecting joint 45 is connected at its supplied fluid outlet 46 liquid-tightly coupled through an O-ring, while this joint 45 is made connectable at its inlet port 44 peripherally threaded properly to a service fluid supply pipe (not shown), and the outlet 41 of the other solenoid valve 10G1 is closed by means of a cut-off plug 47 fitted over the outlet 41. Consequently, a fluid supplied from the service fluid supply pipe to the joint 45 and discharged out of its outlet 46 is caused to flow into both of the solenoid valves 10G and 10G1 which are mutually connected on their fluid supply side 13. Other constituents and their function, including the opening and closing operation of the both solenoid valves 10G and 10G1, are the same as those in the foregoing embodiments of FIGS. 1-3 and 7, and the same constituents as those in the embodiments are denoted by the same reference numerals.
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A solenoid valve is formed with a first pressure chamber defined to be above a valve seat with and from which a valve member engages and disengages and to communicate with a fluid supply side within a valve housing, and solenoid means mounted to the valve housing with a pilot valve interposed between them while defining a pilot chamber below the pilot valve and a second pressure chamber above the pilot valve, the pilot chamber communicating with the first pressure chamber and with a fluid discharge side of the valve member. The pilot valve actuated by the solenoid means for a relatively smaller displacement allows the main valve member to be actuated to open and close the valve, whereby the solenoid means and eventually the entire valve can be minimized in size, and any impurity contained in flowing fluid can be prevented from adhering to a movable member in the solenoid means for assuring a highly reliable operation of the valve for a long term.
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BACKGROUND OF THE INVENTION
The present invention relates generally to the field of frequency modification, and more specifically, to the field of multi-mode cellular telephone frequency conversion and modulation.
Multi-mode communication devices are capable of operating in two or more different modes for use in two or more different types of communication systems. Among various types of radios and radio communication devices, one type of multi-mode communication device is a dual-mode cellular telephone capable of operating in both analog FM (frequency modulation) systems and digital CDMA (code division multiple access) systems.
CDMA/FM cellular telephones and other communication devices typically include circuitry defining multiple signal paths for processing signals according to the multiple modes supported by the device. Normally, the various signal paths connect at some controlled switched point. It has been found that typical schemes for connecting the signal paths and switching between the various modes of communication can be improved. In one prior CDMA/FM cellular telephone scheme, the CDMA transmit signal path includes a CDMA IF (intermediate frequency) mixer section for up-converting a low frequency IF CDMA transmit signal into a higher frequency IF CDMA transmit signal. A separate FM transmit signal path includes an FM modulation section for modulating an intermediate carrier frequency with an FM audio signal to produce an FM IF signal. Subsequent to the FM modulation section and the CDMA IF mixer section, the two signal paths join each other in an adjustable amplifier section. Unfortunately, by keeping the signal paths separate until the IF stage, this connection scheme requires a large number of components, resulting in a larger, more expensive communication device.
There is, therefore, a need in the industry for a scheme for connecting signal paths of multi-mode communication devices which addresses these and other related, and unrelated, problems.
SUMMARY OF THE INVENTION
Briefly described, the present invention includes, in its most preferred embodiment as applied to a transmit section of a CDMA/FM cellular telephone, a dual-function double balanced mixer circuit which provides a scheme for connecting a CDMA IF signal path with an FM audio signal path. The double balanced mixer circuit includes a double balanced mixer with an external LC (inductor-capacitor) tank connected to both a PLL (phase lock loop) and an FM audio signal. The oscillator inputs of the double balanced mixer are connected to the external LC tank. One signal input of the double balanced mixer receives a CDMA low IF signal, while the other double balanced mixer signal input is connected to a microprocessor-controlled switch for selectively unbalancing the balanced mixer while in the FM mode of operation.
During the CDMA mode of operation, the CDMA low IF line carries a signal, while the FM audio line does not carry a signal. Furthermore, the double balanced mixer functions normally to convert the CDMA low IF signal into a CDMA high IF signal which includes the frequency sum and frequency difference of the CDMA low IF signal and the oscillator signal from the external LC tank.
Thus, the double balanced mixer outputs a CDMA high IF signal which does not include either the frequency of the input CDMA low IF signal or the frequency of the oscillator inputs. In the FM mode of operation, the FM audio line, rather than the CDMA low IF line, carries a signal. Since the FM audio line is connected to the external LC tank, the oscillated signal of the external LC tank becomes a carrier signal which is modulated by the FM audio signal so that the oscillator inputs of the double balanced mixer receive an FM IF signal. In addition, in the FM mode of operation, one of the double balanced mixer signal inputs is essentially grounded to unbalance the double balanced mixer. In this way, the double balanced mixer outputs the FM IF signal.
In one preferred embodiment of the present invention, both signal outputs of the double balanced mixer are utilized, with a first output being used during the CDMA mode, and a second output being used during the FM mode. In addition, an FM bypass circuit is connected to the second output. In another preferred embodiment of the present invention, depending on the availability and quality of filters and other components within the cellular telephone, only the first output is used, and the FM bypass circuit is omitted. Alternate embodiments of the present invention include alternate applications of the connection scheme of the present invention in other types of communication devices. Furthermore, the scope of the present invention is also intended to include other circuital arrangements of mixers, such as I & Q baseband modulation and demodulation, as well as double and single side band modulation, etc.
It is therefore an object of the present invention to provide a new double balanced mixer circuit.
Another object of the present invention is to provide a scheme for connecting multiple signal paths within a multi-mode communication device.
Another object of the present invention is to provide a dual-function double balanced mixer circuit.
Yet another object of the present invention is to provide dual-function double balanced mixer circuit which, in one mode, mixes signals for frequency conversion, and, in another mode, modulates a carrier signal.
Still another object of the present invention is to provide a double balanced mixer functioning as a modulation switch.
Still another object of the present invention is to provide an adjustable oscillator circuit providing frequency modulation and providing a frequency source for frequency conversion.
Still another object of the present invention is to provide a double balanced mixer and a control circuit for substantially grounding one input of the double balanced mixer to unbalance the double balanced mixer.
Other objects, features and advantages of the present invention will become apparent upon reading and understanding the present specification, when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram representation of signal paths in a transmit portion of a CDMA/FM dual-mode cellular telephone, including a dual-function double balanced mixer circuit in accordance with one preferred embodiment of the present invention.
FIG. 2 is a schematic representation of the dual-function double balanced mixer circuit of FIG. 1.
FIG. 3 is a schematic representation of the adjustable IF amplifiers circuit of FIG. 1.
FIG. 4 is a schematic representation of the FM bypass circuit of FIG. 1
FIG. 5 is a schematic representation of the mixer of FIG. 2.
FIG. 6 is a block diagram representation of the PLL of FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now in greater detail to the drawings, in which like numerals represent like components throughout the several views, FIGS. 1-6 illustrate one preferred embodiment of the present invention. FIG. 1 is a signal path block diagram representation of a dual-function double balanced mixer circuit 10 located in the middle of a transmit portion 11 of a dual-mode CDMA/FM cellular telephone. In accordance with the preferred embodiments of the present invention, the CDMA/FM cellular telephone, of which the transmit portion 11 forms one part, includes a host of other components which, although not shown in any of the FIGS. 1-6, would be readily understood regarding the operation of, and the need for, such components.
Digital I/Q data lines 12 are shown connected to a D/A (digital-to-analog) converter 14 followed by a baseband modulator 16. One example of an acceptable prior art integrated circuit containing the D/A converter 14 and the baseband modulator 16, in addition to a variety of other components, is the CDMA Baseband Analog ASIC (application specific integrated circuit) available from Qualcomm, Inc. of San Diego, Calif. A CDMA low IF line 18 carries CDMA signals in analog form at a "low" (relatively) intermediate frequency from the baseband modulator 16 to the dual-function double balanced mixer circuit 10. One example of an acceptable "low" intermediate frequency for the signals on the CDMA low IF line 18 is 4.95 MHz.
As is explained in greater detail below, the dual-function double balanced mixer circuit 10 selectively functions in either a CDMA mode of operation or an FM mode of operation. In the CDMA mode, the dual-function double balanced mixer circuit 10 receives CDMA low IF signals through the CDMA low IF line 18, converts the signals into CDMA "high" IF signals, and outputs the signals over a CDMA high IF line 20 to an adjustable IF amplifier circuit 22. One example of an acceptable "high" intermediate frequency for the signals on the CDMA high IF line 20 is 114.99 MHz. In the FM mode of operation, ordinary audio signals are received over the FM audio line 24, modulated into FM IF signals, and output over a modulated FM line 26 to an FM bypass circuit 28. While audio signals normally range between 300 Hz to 10 KHz, one example of an acceptable frequency for signals on the modulated FM line 26 is 128.16 MHz. During the FM mode of operation, the FM bypass circuit 28 outputs the FM IF signals over an FM bypass line 30 to the adjustable IF amplifier circuit 22, along with an FM gain control line 31. Subsequent to the adjustable IF amplifier circuit 22, either CDMA or FM signals travel through an amplified IF line 32 to be processed identically through a conventional up mixer circuit 34, RF amplifier circuit 36, duplexer 38, and antenna 40.
Refer now to FIG. 2, which shows a schematic representation of the dual-function double balanced mixer circuit 10 of FIG. 1. The major components of the dual-function double balanced mixer circuit 10 include a mixer IC (integrated circuit) 50 connected through an external LC tank 52 to a phase locked loop frequency synthesizer IC (PLL) 54. In the CDMA mode of operation, CDMA low IF signals pass over the CDMA low IF line 18, through resistor 60 and capacitor 62 to an "IN A" input on the mixer 50. A mode line 70, under the control of a central microprocessor (not shown), is low (e.g., 0 volts) during the CDMA mode of operation and high (e.g., +5 volts) during the FM mode of operation. As is discussed in more detail below, the transistor 76 functions as a switch to unbalance the mixer 50 by selectively grounding an "IN B" input of the mixer 50 across a resistor 80 during the FM mode of operation.
In addition to the mode line 70, other controls lines connected to the PLL 54 include a reference line 100 extending through an RC (resistor-capacitor) network to an OSC IN input and an OSC OUT output, an enable line 102 resistively coupled to an EN input, a PLL data line 104 resistively coupled to a DATA IN input, a PLL clock line 106 resistively coupled to a CLK input, and a lock detect line 112 RC-coupled to an LD output. One example of an acceptable reference frequency for the reference line 100 is 19.8 MHz provided by a temperature-compensated crystal oscillator (not shown). The PLL 54 is shown connected to the LC tank 52 through an "F IN" input connected to a tank frequency line 108 and a "PD OUT" output connected to a frequency/phase modification line 110. As would be understood by one reasonably skilled in the industry the PLL 54 outputs a DC voltage onto the frequency/phase modification line 110 to cause the LC tank 52 to establish and maintain a particular frequency on the tank frequency line 108. The particular frequency maintained by the LC tank 52 and the PLL 54 is determined by data loaded into the PLL 54 through the PLL data line 104 from the central microprocessor (not shown). Examples of acceptable frequencies maintained on the tank frequency line 108 are 119.94 MHz for the CDMA mode of operation and 128.16 MHz for the FM mode of operation.
After being modified as a result of passing through a conventional filter/noise RC network 118, the DC voltage applied to the frequency/phase modification line 110 by the PLL 54 reaches the LC tank 52. The LC tank 52 includes resistors 120, 126 and 140, capacitors 128, 132, 134, and 136, and inductor 130. After encountering an isolation resistor 120, the DC voltage adjusts the effective capacitance created by varactor diodes 122 and 124. The capacitive and inductive ability of the LC tank 52 cooperates with amplifiers internal to the mixer 50 (FIG. 5) to create and sustain an oscillation which is fed into an "OSC 1" input on the mixer 50, as well as looped back to the PLL 54 through the tank frequency line 108 for continual adjustment to assure consistency of frequency.
In the CDMA mode of operation, no signals appear on the FM audio line 24, signals do appear on the CDMA low IF line 18, and the mode line 70 is low so that the mixer 50 operates in a normal, balanced manner by mixing the signals coming in the IN A input and the OSC 1 input. Accordingly, a signal containing the frequency sum and frequency difference are output through an OUT A, after which the signal is matched to, and filtered by, a SAW BPF (surface acoustic wave band pass filter) circuit 152 which passes the frequency difference onto the CDMA high IF line 20. In accordance with the example frequencies discussed above, the 4.95 MHz CDMA low IF signal is mixed with a 119.94 MHz oscillator frequency on OSC 1 so that a 114.99 Mm signal appears on the CDMA high IF line 20. As is typical with a double balanced mixer, the input frequencies (4.95 MHz and 119.94 MHz) do not appear in the signal coming from the OUT A output.
In the FM mode of operation, no signals appear on the CDMA low IF line 18, signals do appear on the FM audio line 24, and the mode line 70 is high so that the IN B input of the mixer 50 is grounded across resistor 80 to unbalance the mixer 50. As a result, the frequency appearing on the OSC 1 input is simply passed through to both the OUT B and OUT A outputs, of which only the OUT B output is used in the FM mode of operation. By directing audio signals into the LC tank 52 as shown, the audio signal modulates the oscillating frequency. In the FM mode, the oscillating frequency determined by the PLL 54 is different from that of the CDMA mode. One example of an acceptable FM oscillating frequency is 128.16 MHz, so that the modulated FM signal appearing on the modulated FM line 26 is also centered on 128.16 MHz, with a 15 KHz shift around that frequency as a result of the audio input.
Refer now to the FIG. 3, which shows a schematic representation of the adjustable IF amplifier circuit 22 of FIG. 1. The CDMA high IF line 20 is shown connected to the first of a series of dual-gate FETs 160, 162, 164 (field-effect transistors) which amplify signals on that line, in the CDMA mode, according to levels on the TX AGC (transmit automatic gain control) line 170, as determined by a separate automatic gain control circuit (not shown). During the FM mode of operation, the mode line 70 disables the CDMA high IF line 20 so that the FET 164 amplifies onto the amplified IF line 32 signals received through the FM bypass line 30 at a gain determined by the FM gain control line 31. Referring also to FIG. 4, the FM bypass circuit 28 essentially provides a mechanism for switching the FM bypass line 30 off during the CDMA mode through operation of transistor 200 and FET 202, and setting the gain level through the FM gain control line 31 through operation of the switch 206.
FIGS. 5 and 6 show more detailed views of the mixer 50 and PLL 54 of FIG. 2, respectively. To those skilled in the art, it is apparent how grounding the IN B input will unbalance the Gilbert cell multiplier configuration of the mixer 50 and change the internal balance between the internal transistor pairs so that the frequency of the signal on the OSC I input appears at the OUT B and OUT A outputs. One example of an acceptable mixer 50 is the prior art Double-balanced mixer and oscillator SA602A from Signetics Corporation of Sunnyvale, Calif. With reference to FIG. 6, the PLL 54 receives a reference signal through the OSC IN input onto path 350 which feeds the signal into an oscillator 400 which delivers the signal to a 15-stage counter 404. The counter 404, as determine by a 15-bit register 408, divides the reference frequency down to an internal frequency, such as 60 KHz. Similarly, the frequency entering the F IN input, after traveling through a path 356 and an input amplifier 418, is divided down to the same internal frequency by a 16-stage counter 416 as determined by a 16-bit register 414. A shift register and control logic portion 410 passes the appropriate values into the registers 408, 414 to equate the frequencies which exit the counters 404, 416 and enter a phase/frequency detector and control portion 406 and a lock detector and control portion 420. The phase/frequency detector and control portion 406 compares the two frequencies and outputs onto a path 360, which leads to the PD OUT output, a signal which is either low or high until the frequencies are similar, and then adjusts upward or downward to effect a phase adjustment, until settling at a point where the frequencies and phases match. At that point, the lock detector and control portion 420 outputs a signal on path 362 to the LD output to indicate that the frequency/phase locked condition to the central microprocessor (not shown). One example of an acceptable PLL 54 is the prior art MC145170 from Motorola, Inc. of Schaumburg, Ill.
The present invention further includes a second preferred embodiment which is identical in structure and operation to the first preferred embodiment except for the following differences. The main differences are that, with reference to FIGS. 1-3, both CDMA and FM IF signals are (during separate modes) directed through the OUT A output of the mixer 50, and the FM bypass circuit 28 is omitted. Furthermore, the frequency of the CDMA mode oscillation is altered to result in matching frequencies on the CDMA high IF line 20. As an acceptable example, according to the second preferred embodiment, the oscillator frequency at the OSC 1 input to the mixer 50 would be the same 128.16 MHz during the FM mode, but would be 133.11 MHz for the CDMA mode so that the resulting frequency on the CDMA high IF line 20 is 128.16 MHz for both FM and CDMA modes. Clearly, the saw filter 152 would also change to pass that particular frequency. As discussed above, data loaded into the PLL tunes the frequency at the OSC 1 input of the mixer 50. In the adjustable IF amplifier circuit 22 (FIG. 3), the circuit extending from the mode line 70 is deleted along with the FM bypass line 30, FM gain control line 31, and resistor 178. In addition, the resistor 176 and capacitor 184 are appropriately sized in accordance with similarly-placed resistors 174, 172 and capacitors 182, 180.
While the embodiments of the present invention which have been disclosed herein are the preferred forms, other embodiments of the present invention will suggest themselves to persons skilled in the art in view of this disclosure. Therefore, it will be understood that variations and modifications can be effected within the spirit and scope of the invention and that the scope of the present invention should only be limited by the claims below.
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A circuit for connecting multiple signal paths within a multi-mode communication device includes a double balanced mixer circuit selectively functioning as a modulation switch during an unbalanced state. As applied to a transmit section of a CDMA/FM cellular telephone, a dual-function double balanced mixer circuit connects a CDMA IF signal path with an FM audio signal path. The double balanced mixer circuit includes a double balanced mixer connected through oscillator input to an external LC (inductor-capacitor) tank connected to both a PLL (phase lock loop) and an FM audio signal. One signal input of the double balanced mixer receives a CDMA low IF signal, while the other double balanced mixer signal input is connected to a microprocessor-controlled switch for selectively unbalancing the balanced mixer while in the FM mode of operation.
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This application is a national stage completion of PCT/EP2006/006190 filed Jun. 27, 2006, which claims priority from German Application Serial No. 10 2005 031 764.2 filed Jul. 6, 2005.
FIELD OF THE INVENTION
The invention relates to a method for controlling a drivetrain of a vehicle with one prime mover and one transmission the ratio of which can be automatically varied within a range of ratios in a continuous and/or stepped manner, according to target speeds adjustable at any time, via a speed control of the vehicle and the inclination of the vehicle relative to the longitudinal axis of the vehicle.
BACKGROUND OF THE INVENTION
Vehicles know from the practice are designed for increasing the traveling comfort with so-called driving speed control units, by way of which a specific speed value of the vehicle speed during a driving operation of the vehicle can be automatically adjusted without the driver actuating an accelerator pedal and can also be automatically kept in case of changed operation conditions of the vehicle. At the same time, it is provided in the known systems to obtain the adjusted speed value or the requested target speed of the vehicle by varying an input torque of the prime mover, by an adequate command to a motor control and control of a brake control of a brake system of the vehicle.
It is further provided that in case of a driver's actuation of the brake pedal or accelerator pedal the vehicle speed control is terminated, the driver being able to reactivate the vehicle speed control via an adequate command device—such as by pressing a button and automatically to readjust the value of the speed adjusted prior to the actuation of the brake pedal or the accelerator pedal via the vehicle speed control.
There have been additionally developed for further improvement of the traveling comfort, so-called adaptive vehicle speed controls by way of which a distance control, together with an automatic speed control, can be carried out. Such adaptive vehicle speed controls control the system of the vehicle so that the vehicle is automatically decelerated when, for example, the vehicle drops below a certain distance from an object or a requested target driving speed is exceeded during a descent of the vehicle. If after engagement of the adaptive traveling speed control, it is detected that the requested distance value has again been exceeded or the requested target speed of the vehicle again has been reached, the originally requested operating condition of the vehicle is reproduced, it being possible under certain circumstances to accelerate the vehicle by adequate control of the prime mover to the requested target speed.
To support a road speed control or an adaptive road speed control, when downhill travel of a vehicle is detected, special programs with special shifting characteristic lines, coordinated with downhill travel, are started so as to adjust a brake or thrust torque on the output of the drivetrain of the vehicle such that the braking system of the vehicle can be unloaded during long descents.
DE 28 52 195 A1 has disclosed a control device for an automatically shifting transmission by way of which a driving strategy is assisted during mountain travel by a mountain detection. The mountain detection is also used during an activated speed control or in the course of a cruise control transmission in order to control, during an ascent, for example, the transmission by shift characteristic lines which request an upshift only when the rotational speeds of the prime mover are higher than in flat country and are set by way of the greater hysteresis between upshift and downshift characteristic lines.
From DE 40 37 248 A1 has become known for assistance of a vehicle speed control to release, in the transmission, at least one downshift in direction of a lower transmission gear and/or trigger the closing of a converter clutch during an ascent so as to select the gear of a transmission adequate at the moment for the speed control.
However, the last two mentioned procedures known from the prior art have the disadvantage that the methods can be coordinated only to an insufficient extent with different gradient values and changed vehicle loads wherefore they do not assist a traveling speed control to the extent needed for greater traveling comfort.
This means that known descent detections during downhill travel of a vehicle with simultaneously active travel speed control or simultaneously active adaptive travel speed control do not make available the functionality desired inasmuch as the varying states of the vehicle, due to changing loads and to the constantly varying travel profiles, cannot be covered via application of the shifting characteristic lines of a transmission and a driver is often compelled when operating a vehicle adequately to counteract divergences from the required target speed by manual engagements such as by actuating an accelerator pedal or brake pedal.
Should the driver wish to prevent the exit from the traveling speed control, there remains only the manual engagement via limiting positions of a change to a tip driving program, the driver having to react to changes of the downhill gradient either with downshift or upshift requests so as to be able to adjust the requested target speed of the vehicle.
Therefore, the problem on which this invention is based is to make available a method for the control of a drivetrain of a vehicle with one prime mover and one transmission by way of which a target speed of the vehicle, under active drive speed control, can be adjusted or kept during an ascent without manual engagements by the driver even under changing operating conditions.
SUMMARY OF THE INVENTION
In the course of the inventive method, a drivetrain of a vehicle is controlled with a prime mover and with a transmission whose ratio can automatically be controlled in a continuous or stepped way within a range of ratios depending on target speeds of the vehicle that are preset or can be preset via a travel speed control of the vehicle and current inclinations of the vehicle relative to a longitudinal axis thereof. While the travel speed control is active and the actual speed of the vehicle diverges from a preset target speed of the vehicle, a request to change the current ratio of the transmission is generated if it has been determined that the output torque that can be represented by the actual ratio of the transmission at the output of the drivetrain is smaller than a threshold value or smaller than an output-end torque required to adjust the preset target speed of the vehicle, the ratio of the transmission being varied such that the output torque that can be represented on the output is altered in a direction of the output torque required to set the target speed of the vehicle.
Thus in the inventive method, both a divergence of the actual speed of the vehicle from a preset target speed of the vehicle and an output torque that can be represented at any time on the output are monitored and a divergence from the actual speed of the vehicle due to a change of the actual ratio of the transmission is counteracted by the fact that, for example, when the target speed of the vehicle is exceeded during a descent the ratio of the transmission is increased in a manner such that the output torque that can be represented on the output is changed in the direction of the output torque required to adjust the target speed of the vehicle.
Compared to traditional methods, it is advantageously possible by the inventive procedure to adapt the ratio of the transmission throughout all operational ranges of the vehicle to the currently existing state of the vehicle, that is, to the actually existing inclination of the vehicle, the actual load of the vehicle and the target speed of the vehicle requested via the speed control of the vehicle, whereby manual adjustments by a driver to keep the present target speed of the vehicle are easily prevented and time consuming and costly applications are not needed like in the conventionally operated transmissions.
BRIEF DESCRIPTION OF THE DRAWING
The invention will now be described, by way of example, with reference to the accompanying drawing in which:
The sole FIGURE shows several curves of an operation state parameters of a vehicle corresponding with each other and additional operation parameters used over the time while applying the inventive method during an operation state curve of the vehicle by way of example and which adjust themselves in an inventive control of an automatic transmission.
DETAILED DESCRIPTION OF THE INVENTION
It is to be understood by the expression “automatic transmission”, in the sense of the instant invention, all transmissions having an automatic gear change and designated as stepped automatic transmissions or as continuously variable automatic transmissions. To these belong the double clutch transmissions, the fully automated, claw or synchronous transmission, conventional fully automatic mechanical transmission, so-called CVT transmissions and combinations thereof.
In the FIGURE are shown superimposed, several curves of operating state parameters of a vehicle, the same as additional operation parameters or characteristics which correspond to each other and adjust themselves during an operating state curve of a vehicle under activated vehicle speed control during a descent of a vehicle with changing downhill gradients or changing vehicle inclination.
Before the point in time T_ 0 , there is activated in the transmission, which is here a 6-gear stepped automatic transmission, a sixth forward drive step as actual ratio i_ist. The current actual speed v_ist of the vehicle essentially corresponds to a target speed v_ziel of the vehicle preset by the drive and adjusted or kept by a vehicle speed control.
A motor torque m_mot of a prime mover of the drivetrain of the vehicle observed is lowered in the manner shown form the travel speed control or the engine control coupled therewith in order to keep an actual speed v_ist of the vehicle at the preset value of the target speed v_ziel of the vehicle by representing a corresponding engine braking torque on the output of the vehicle.
One other curve of a vehicle acceleration differential a_diff still has, despite considerable reduction of the engine torque m_mot of the prime mover, a slight change in direction of a threshold value a_schwell. By the reduction of the engine torque m_mot combined with the actually adjusted ratio i_ist, the prime mover also makes a thrust torque or input torque available on the output under which the acceleration of the vehicle increases only slightly and the actual speed v_ist of the vehicle substantially corresponds to the target speed of the vehicle. The vehicle acceleration differential a_diff corresponds momentarily to a difference from a nominal acceleration of the vehicle determined with the aid of an actual input torque of the prime mover and an actually determined current acceleration of the vehicle, there being easily taken into account at this point both the actual uphill gradient and an actual load state of the vehicle.
Alternative to this, it can also be provided that the actual road inclination or inclinations of the vehicle are determined by way of an inclination sensor and are used for control of the drivetrain, an actual vehicle load being determined by other adequate steps in this procedure.
At a point in time T_ 1 at which the engine torque m_mot is at its lowest value and on the output abuts the highest possible thrust torque that can be represented with the actual ratio i_ist of the transmission, the actual speed v_ist of the transmission increasingly begins to diverge from the target speed v_ziel. This means that the engine braking torque of the prime mover, abutting on the output of the vehicle and correspondingly changed via the actual ratio i_ist of the transmission, does not correspond to the output torque required to adjust the target speed of the vehicle.
Therefore, at a point in time T_ 2 , when the actual speed v_ist of the vehicle exceeds a threshold value v_schwell of the vehicle speed, which is above the requested target speed v_ziel of the vehicle speed, the ratio i_ist of the transmission is reduced by a downshift.
The request for the downshift in the transmission at the point in time T_ 2 accordingly results because, due to maximum lowering of the engine torque m_mot and the exceeding of the threshold value v_schwell of the vehicle speed dependent on the output rotational speed and ratio with a simultaneous falling below, the applied threshold value a_schwell of the differential vehicle acceleration a_diff, it is detected that the engine braking action on the side of the prime mover no longer suffices to make setting or maintaining the requested target speed v_ziel of the vehicle possible for the actual downhill gradient.
Alternative to this, it can also be provided that the downshift be requested already when the output torque of the engine torque falls below a predefined threshold value which is lower than the maximum output torque adjustable on the output with the current actual ratio.
At the same point in time T_ 2 , a first timer TIMER 1 is simultaneously started until, at its expiration, one other change of the ratio i_ist of the transmission is prevented. This means that during the activated first timer TIMER 1 , neither an upshift nor a downshift is carried out in the transmission. In addition, during the activated first timer TIMER 1 , a filtered actual acceleration of the vehicle is determined and evaluated, one other downshift or further increase of the actual ratio i_ist of the transmission being discontinued when it has been established that the actual speed v_ist of the vehicle changes after the downshift of the ratio in direction of the requested target speed v_ziel.
The actual acceleration of the vehicle is here calculated from the output rotational speed of the vehicle and subsequently filtered via a mean value filter, in order to evaluate irregularities of the output rotational speed signal with an inertia such that the control of the transmission is not negatively affected by the irregularities occurring in the curve of the actual acceleration.
By the shift prevention existing during the active first timer TIMER 1 , there are immediately prevented other downshifts that follow the downshift which, under certain circumstances, are not needed for adjusting the target speed of the vehicle and may, in turn, have as consequence occasional upshifts that follow. Such operating state curves, known from the prior art, which are designated as pendulum shifts, impair the traveling comfort to an undesirable extent.
Therefore, after the downshift, by activating the first timer TIMER 1 time is next given to the system vehicle to increase the engine brake torque, abutting on the output of the vehicle and, accordingly, is able to counteract the resistance on hill descent affecting the vehicle due to the downhill gradient.
At a point in time T_ 3 at which the first timer TIMER 1 has expired, there is requested one other increase of the actual ratio i_ist of the transmission or one other downshift since, when the vehicle travel speed control is activated, a divergence is detected of the actual speed v_ist from the preset or requested target speed v_ziel of the vehicle, which divergence is greater than the threshold value v_schwell of the vehicle speed. In case of such a divergence of the actual speed v_ist of the vehicle from the target speed v_ziel, it is determined that the output torque that can be represented on the output of the output train with the actual ratio i_ist of the transmission is smaller than an output side input torque required to adjust the present target speed v_ziel when the filtered actual acceleration of the vehicle evaluated during the active first timer TIMER 1 is higher than an applied threshold value.
At the point in time T_ 3 , since all the aforesaid conditions have been satisfied, there results a second downshift starting from the fifth forward running step of the transmission to its fourth forward running step, the first timer TIMER 1 being re-started at the point in time T_ 3 of the first timer TIMER 1 .
As result of the repeated downshift in the transmission, the actual speed v_ist of the vehicle falls below the threshold value v_schwell of the vehicle speed in the direction of the requested target speed v_ziel of the vehicle while the differential vehicle acceleration a_diff, which corresponds to a calculated mountain characteristic and is equivalent to an actual vehicle inclination taking into consideration an actual load state of the vehicle when the motor torque m_mot remains the same, has a slight increase in direction of the threshold value a_schwell of the differential vehicle acceleration. The slight rise of the curve of the vehicle differential acceleration a_diff indicates thereupon that after the second downshift there is an increase in drive torque applied to the output of the vehicle. Besides, by assimilation of the actual speed v_ist to the threshold speed v_ziel after expiration of the first timer TIMER 1 , another downshift is not required in the transmission.
At the point in time T_ 4 , the motor torque m_mot is again raised so as to keep the actual speed v_ist at the value of the target speed v_ziel. Since the curve of the differential vehicle acceleration a_diff is substantially at a low level as a result of a small downhill gradient, the motor torque m_mot has to be increasingly raised, in the manner shown, so as to hold the actual speed v_ist at the value of the target speed v_ziel.
Such an operation state curve leads to a point in time T_ 5 for activation of a second timer TIMER 2 while in it is checked whether the motor torque m_mot is permanently stronger than an applicable gear-dependent performance graph which varies according to the output rotational speed of the vehicle, the same as to the vehicle differential acceleration a_diff. This inquiry is answered in the positive at a point in time T_ 6 at which the second timer TIMER 2 expires, at which point an upshift from the fourth forward running step to the fifth forward running step is requested and carried out. Thereafter the motor torque m_mot is adjusted under control, in the manner shown in the FIGURE, so that the actual speed v_ist of the vehicle corresponds from now on to the target speed v_ziel of the vehicle.
In order to prevent one other upshift immediately following the upshift at the point in time T_ 6 , at the point in time T_ 6 , a third timer TIMER 3 is started during which a change of the ratio of the transmission is prevented. This means that immediately after expiration of the third timer TIMER 3 , one other upshift can be carried out when the conditions provided therefor are satisfied.
With this procedure, a sequential upshift is carried out in the transmission in order to be able to react to light and strong changes of the travel profile by a single shift or by multiple shifts following each other to an extent adequate for preserving the present target speed v_ziel of the vehicle.
Alternative to the observation of the actual motor torque of the prime mover, it is also possible to monitor a virtual acceleration pedal value preset by the motor control since this is equivalent to the actually adjusted motor torque. The virtual acceleration pedal value is used for adjusting the motor torque since, in activated travel speed control, an activation of the acceleration pedal on the driver's side is omitted and, from this position, no corresponding request to adjust the motor torque abuts on the prime mover of the vehicle.
In the inventive method, in case of detection of a downhill travel and of exceeding an applicable speed hysteresis, which here corresponds to the difference between the threshold value v_schwell of the vehicle speed and the requested target speed v_ziel of the vehicle, there is requested in the vehicle, independently of a driving or shifting program requested in a transmission control, a change of the ratio of the transmission, i.e., either a downshift or an upshift is requested in order to adjust or regulate the actual speed v_ist of the vehicle in direction of the requested target speed v_ziel in a manner optimally adapted to the actual operating state of the vehicle when the output torque representable on the output with the actually activated actual ratio i_ist of the transmission cannot be made to coincide with the output torque required for the adjustment of the requested target speed v_ziel or is adjustable to this value or an applied threshold value of the output torque.
To ensure that the ratio of the transmission is not changed in a manner impairing the traveling comfort or too low a gear be kept too long, in the inventive method, it is checked whether the cycle to the automatic request of an upshift has not been entered into under activated traveling speed regulation.
It is provided that the entry occurs immediately when it is detected that the differential vehicle acceleration a_diff is lower than the threshold value a_schwell, the motor torque m_mot or the virtual acceleration pedal value is lower than an applied threshold and the actual speed v_ist is higher than the target speed v_ziel plus a hysteresis applicable in accordance with output rational speed and ratio or is higher than the threshold value v_schwell. If the aforementioned conditions are satisfied, a downshift is requested according to the invention. The first timer TIMER 1 is simultaneously started while, together with preventing an upshift, an eventually requested added downshift is also prevented.
Only after expiration of the first timer TIMER 1 and simultaneous fulfillment of the above mentioned entry conditions is another downshift requested and carried out in the transmission, there being thereafter activated, in turn, by the reactivated first timer TIMER 1 the time limited shifting obstacles.
If the motor torque m_mot or the virtual accelerator pedal value is permanently higher than a gear-dependent applied characteristic field, the ratio of the transmission is reduced by a sequential upshift routine until the system vehicle is adapted to the actual travel profile change so that the requested target speed v_ziel can be kept by the travel speed control by running the motor in a consumption friendly manner as possible.
In addition, it is possible by evaluation of the filtered vehicle acceleration in the presence of a positive vehicle acceleration and of a motor torque greater than the threshold value, to prevent an upshift and, at the same time, verify whether an upshift has been carried out in the transmission in order to maintain the actual speed v_ist of the vehicle at the level of the requested target speed v_ziel of the vehicle.
With the inventive method is basically verified whether actual motor braking no longer suffices for the actual downhill gradient and thus, when the entry conditions have been met and the set target speed v_ziel has been exceeded, in addition to an applicable hysteresis, a downshift is automatically carried out in the transmission. But if the conditions have not been satisfied for an exit from the inventive control routine of the transmission or of the input train by a flat travel profile, the same as a passage from a coasting operation to a traction operation of the input train, the exit does not occur immediately, but only when the conditions for an exit have been durably met.
Requested upshifts in the transmission are sequentially performed since, after each upshift has taken place, the behavior of the vehicle, which is characterized by the accelerator pedal position, driving acceleration and the like, is first evaluated within an applicable time window, that is, a third timer TIMER 3 in this case. With the aid of this information, it is now possible, with further observation regarding the applicable exit conditions, to decide whether one other upshift has to be carried out or whether a re-entry in the routine for an automatic upshift is suitable.
The automatic shifting during activated vehicle speed control complements the functionality of a cruise control transmission operation of a vehicle, especially during a descent of a vehicle, the inventive method being also adequate for improving the traveling comfort when mountain crossing, since by way of the method decisions can be used for upshifts, downshifts or maintaining the gear.
The driving strategy applicable to stepped automatic, CVT, double clutch, automated mechanical transmissions or similar types of transmissions advantageously offers the possibility of better tuning the selection of gear to the characteristics of the vehicle in the cruise control operation and of better being able to take into account changes of the driving profile. This means that in sharp downhill gradients, the transmission automatically downshifts in order to maintain the speed chosen by the driver, an automatic upshift being additionally requested when the driving surface again becomes more level.
In an advantageous alternative of the inventive method, there exists the added possibility of controlling the transmission according to gradient information signals relative to the ground actually traveled by the vehicle or to the ground to be traveled in the future, which signals are sent by a transmitter device to a receptor device of the vehicle so that there is an automatic activation of a lower gear on dangerous downhill gradients. In this case, such information can be transmitted to the vehicle by a GPS system.
In addition or alternative to this, it can also be provided that the inventive control is adapted for frequently traveled routes, taking into account the optimal gear to be activated at the moment, so as to make assisting possible to the extent sought a travel control.
In another advantageous alternative of the inventive method, it is provided in a vehicle with automatic speed and distance control that this system takes effect directly on the gear proposed for the vehicle thus protecting or releasing the brakes of the vehicle by an eventual downshift.
Moreover, it is possible to expand the above described method to other vehicle components such that a brake torque can be represented in the output. It is thus possible for reducing the actual speed of a hybrid vehicle, to activate a load operation of the accumulator elements so as to adjust a required output torque on the output for adjusting or regulating the target speed of the vehicle.
REFERENCE NUMERALS
a_diff vehicle acceleration differential
a_schwell threshold value of the vehicle acceleration differential
i_ist actual ratio
m_mot motor torque
v_ist actual speed of the vehicle
v_schwell threshold value of the vehicle speed
v_ziel target speed of the vehicle
t time
T 1 to T 6 point in time
TIMER 1 first timer
TIMER 2 second timer
TIMER 3 third timer
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A method for controlling a vehicles drivetrain including an engine and automatic transmission, such that transmission ratios are shifted within a range of transmission ratios in a continuous and/or stepped manner as function of preset target speeds that are adjustable via a vehicle speed control and actual vehicle inclinations in relation to the vehicles longitudinal axis. When the actual speed of the vehicle differs from a preset threshold speed, a request to change an actual ratio of the transmission is generated, if it has been determined that the output torque is smaller than a threshold value or an output torque required to adjust the preset threshold speed of the vehicle. The ratio of the transmission is shifted so the torque applied to the output is modified toward the output torque required to adjust the threshold speed.
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FIELD OF THE INVENTION
[0001] This invention relates to a process of manufacturing asymmetric gas separation membranes. More particularly, this invention relates to the use of a solvent mixture that allows for manufacture of asymmetric gas separation membranes with improved properties.
BACKGROUND OF THE INVENTION
[0002] Polymeric gas-separation asymmetric membranes are well known and are used in such areas as production of oxygen-enriched air, nitrogen-enriched streams for blanketing fuels and petrochemicals, separation of carbon dioxide from methane in natural gas, hydrogen recovery from ammonia plant purge streams and removal of organic vapor from air or nitrogen.
[0003] As is well known to those skilled in the art, the ideal gas-separation membrane would combine high selectivity with high flux. There are three key parameters that determine the commercial viability of a membrane for gas separation. The first is the membrane's separation factor towards the gas pair to be separated. The second parameter is the membrane permeation flux which dictates the membrane area requirement. The higher the permeation flux, the smaller the membrane area required. The third parameter is the working life of membrane. Commercially available asymmetric flat sheet gas separation membranes containing cellulose diacetate and cellulose triacetate are made from casting a dope containing a solvent mixture of 1,4 dioxane, and N-methylpyrrolidone together with one or two suitable non-solvents. Similarly, asymmetric membranes also have been made from polyimides such Matrimid® which is the condensation product of 3,3′,4,4′-benzophenone tetra-carboxylic dianhydride and 5(6)-amino-1-(4′-aminophenyl)-1,3,3′-trimethylindane from Ciba-Giegy Corporation, or Victrex® a Polyethersulfone 6010 manufactured by BASF Corporation or a blended polymer dope containing 1,4 dioxane, or NMP, N,N′-dimethylacetamide, dimethylformamide or the mixtures of these solvents. In prior art processes, 1,4 Dioxane was found to be needed in the casting dope to form the extremely thin integral dense skin on top of the resulting asymmetric membrane. Without the use of 1,4 Dioxane, the result was either an opened membrane (an ultra filtration membrane) or a very dense membrane would result from the process. In either case, the membrane would be unsuited for gas separations. For the same reason, because the polyimide polymer sold under the trade name P84 from HP Polymer GmbH and Ultem from General Electric does not dissolve in 1,4 dioxane asymmetric membranes can only be made from the NMP casting dope unless the temperature of dope is raised to about 100° C. prior to the phase inversion process.
SUMMARY OF THE INVENTION
[0004] In the present invention we have discovered that the use of a 1,3 dioxolane solvent for the polymer or the polymer blend dope provides integrally skinned asymmetric membranes with superior permeation flux and selectivity. This solvent has a boiling point of 75° C., forms very stable homogeneous solutions with cellulose diacetate/cellulose triacetate blended polymer, Matrimid polyimide, Ultem polyetherimide, P84 and P84HT polyimide polymers respectively and it is 100% miscible with water. Cellulose diacetate/triacetate blended asymmetric membranes, Matrimid polyimide asymmetric membranes, Matrimid/Polyethersulfone asymmetric blended membranes and P84/Polyethersulfone asymmetric blended membranes have been successfully made with a casting dope containing 1,3 dioxolane and NMP solvents in 2:1 ratio and water as the coagulation bath. The polymers become the continuous polymer matrix in the membrane.
[0005] Some preferred polymers that can be used as the continuous blend polymer matrix include, but are not limited to, cellulosic polymers such as cellulose acetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate, polysulfones, sulfonated polysulfones, polyethersulfones (PESs), sulfonated PESs, polyethers, polyetherimides such as Ultem (or Ultem 1000) sold under the trademark Ultem®, manufactured by GE Plastics, and available from GE Polymerland, and polyamides; polyimides such as Matrimid sold under the trademark Matrimid® by Huntsman Advanced Materials (Matrimid® 5218 refers to a particular polyimide polymer sold under the trademark Matrimid®) and P84 or P84HT sold under the tradename P84 and P84HT respectively from HP Polymers GmbH; polyamide/imides; polyketones, polyether ketones; and microporous polymers.
[0006] The non-solvents may include methanol, ethanol, isopropanol, acetone, methylethylketone, lactic acid, maleic acid, malic acid, decane, dodecane, nonane, and octane with a mixture of methanol and acetone, decane, lactic acid being preferred.
[0007] The method of the invention comprises first dissolving at least one polymer miscible polymers in 1,3 dioxolane/NMP solvents by mechanical stirring to form a homogeneous casting dope; then quenching the casting dope into a cold water gelation bath (typically at a temperature in the range of about 0° C. to about 25° C., preferably from about 0° C. to 5° C.) supported by an appropriate support such as a woven or non-woven fabric, silicone coated paper or a film, such as Mylar® polyester film; densifying the skin of the asymmetric membrane in a second water bath at a higher temperature between about 25° C. to about 100° C. (preferably from about 80° C. to about 86° C.; then removing the water from the membrane at a drying temperature that can range from about 20° C. to 150° C. (preferably from about 65° C. to 70° C.) and finishing by coating the surface of the asymmetric membrane with a thermally curable or UV curable polysiloxane or other suitable coating.
DETAILED DESCRIPTION OF THE INVENTION
[0008] In the present invention we have discovered that the use of a 1,3 dioxolane solvent for the polymer or the polymer blend dope provides integrally skinned asymmetric membranes with superior permeation flux and selectivity. This solvent has a boiling point of 75° C., forms very stable homogeneous solutions with cellulose diacetate/cellulose triacetate blended polymer, Matrimid polyimide, Ultem polyetherimide, P84 and P84HT polyimide polymers respectively and it is 100% miscible with water. Cellulose diacetate/triacetate blended asymmetric membranes, Matrimid polyimide asymmetric membranes, Matrimid/Polyethersulfone asymmetric blended membranes and P84/Polyethersulfone asymmetric blended membranes have been successfully made with a casting dope containing 1,3 dioxolane and NMP solvents in 2:1 ratio and water as the coagulation bath. The polymers become the continuous polymer matrix in the membrane.
[0009] Typical polymers suitable for membrane preparation as the continuous polymer matrix can be selected from, but are not limited to, polysulfones; sulfonated polysulfones; polyethersulfones (PESs); sulfonated PESs; polyethers; polyetherimides such as Ultem (or Ultem 1000) sold under the trademark Ultem®, manufactured by GE Plastics, poly(styrenes), including styrene-containing copolymers such as acrylonitrilestyrene copolymers, styrene-butadiene copolymers and styrene-vinylbenzylhalide copolymers; polycarbonates; cellulosic polymers, such as cellulose acetate, cellulose triacetate, cellulose acetate-butyrate, cellulose propionate, ethyl cellulose, methyl cellulose, nitrocellulose; polyamides; polyimides such as Matrimid sold under the trademark Matrimid® by Huntsman Advanced Materials (Matrimid® 5218 refers to a particular polyimide polymer sold under the trademark Matrimid®) and P84 or P84HT sold under the tradename P84 and P84HT respectively from HP Polymers GmbH; polyamide/imides; polyketones, polyether ketones; poly(arylene oxides) such as poly(phenylene oxide) and poly(xylene oxide); poly(esteramide-diisocyanate); polyurethanes; polyesters (including polyarylates), such as poly(ethylene terephthalate), poly(alkyl methacrylates), poly(acrylates), poly(phenylene terephthalate), etc.; polysulfides; polymers from monomers having alpha-olefinic unsaturation other than mentioned above such as poly(ethylene), poly(propylene), poly(butene-1), poly(4-methyl pentene-1), polyvinyls, e.g., poly(vinyl chloride), poly(vinyl fluoride), poly(vinylidene chloride), poly(vinylidene fluoride), poly(vinyl alcohol), poly(vinyl esters) such as poly(vinyl acetate) and poly(vinyl propionate), poly(vinyl pyridines), poly(vinyl pyrrolidones), poly(vinyl ethers), poly(vinyl ketones), poly(vinyl aldehydes) such as poly(vinyl formal) and poly(vinyl butyral), poly(vinyl amides), poly(vinyl amines), poly(vinyl urethanes), poly(vinyl ureas), poly(vinyl phosphates), and poly(vinyl sulfates); polyallyls; poly(benzobenzimidazole); polyhydrazides; polyoxadiazoles; polytriazoles; poly(benzimidazole); polycarbodiimides; polyphosphazines; microporous polymers; and interpolymers, including block interpolymers containing repeating units from the above such as terpolymers of acrylonitrile-vinyl bromide-sodium salt of para-sulfophenylmethallyl ethers; and grafts and blends containing any of the foregoing. Typical substituents providing substituted polymers include halogens such as fluorine, chlorine and bromine; hydroxyl groups; lower alkyl groups; lower alkoxy groups; monocyclic aryl; lower acryl groups and the like.
[0010] Some preferred polymers as the continuous blend polymer matrix include, but are not limited to, polysulfones, sulfonated polysulfones, polyethersulfones (PESs), sulfonated PESs, polyethers, polyetherimides such as Ultem (or Ultem 1000) cellulosic polymers such as cellulose acetate and cellulose triacetate, polyamides; polyimides such as Matrimid, poly(3,3′,4,4′-benzophenone tetracarboxylic dianhydride-pyromellitic dianhydride-3,3′,5,5′-tetramethyl-4,4′-methylene dianiline) (poly(BTDA-PMDA-TMMDA)), poly(3,3′,4,4′-benzophenone tetracarboxylic dianhydride-pyromellitic dianhydride-4,4′-oxydiphthalic anhydride-3,3′,5,5′-tetramethyl-4,4′-methylene dianiline) (poly(BTDA-PMDA-ODPA-TMMDA)), poly(3,3′,4,4′-diphenylsulfone tetracarboxylic dianhydride-3,3′,5,5′-tetramethyl-4,4′-methylene dianiline) (poly(DSDA-TMMDA)), poly(3,3′,4,4′-benzophenone tetracarboxylic dianhydride-3,3′,5,5′-tetramethyl-4,4′-methylene dianiline) (poly(BTDA-TMMDA)), poly(3,3′,4,4′-diphenylsulfone tetracarboxylic dianhydride-pyromellitic dianhydride-3,3′,5,5′-tetramethyl-4,4′-methylene dianiline) (poly(DSDA-PMDA-TMMDA)), poly[2,2′-bis-(3,4-dicarboxyphenyl)hexafluoropropane dianhydride-1,3-phenylenediamine] (poly(6FDA-m-PDA)), poly[2,2′-bis-(3,4-dicarboxyphenyl)hexafluoropropane dianhydride-1,3-phenylenediamine-3,5-diaminobenzoic acid)] (poly(6FDA-m-PDA-DABA)), P84 or P84HT; polyamide/imides; polyketones, and polyether ketones.
[0011] Some more preferred polymers that can be used as the continuous blend polymer matrix include, but are not limited to, cellulosic polymers such as cellulose acetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate, polysulfones, sulfonated polysulfones, polyethersulfones (PESs), sulfonated PESs, polyethers, polyetherimides such as Ultem (or Ultem 1000) sold under the trademark Ultem®, manufactured by GE Plastics, and available from GE Polymerland, and polyamides; polyimides such as Matrimid sold under the trademark Matrimid® by Huntsman Advanced Materials (Matrimid® 5218 refers to a particular polyimide polymer sold under the trademark Matrimid®) and P84 or P84HT sold under the tradename P84 and P84HT respectively from HP Polymers GmbH; polyamide/imides; polyketones, polyether ketones; and microporous polymers.
[0012] The non-solvents may include methanol, ethanol, isopropanol, acetone, methylethylketone, lactic acid, maleic acid, malic acid, decane, dodecane, nonane, and octane with a mixture of methanol and acetone, decane, lactic acid being preferred.
[0013] The method of the invention comprises first dissolving at least one polymer miscible polymers in 1,3 dioxolane/NMP solvents by mechanical stirring to form a homogeneous casting dope; then quenching the casting dope into a cold water gelation bath (typically at a temperature in the range of about 0° C. to about 25° C., preferably from about 0° C. to 5° C.) supported by an appropriate support such as a woven or non-woven fabric, silicone coated paper or a film, such as Mylar® polyester film; densifying the skin of the asymmetric membrane in a second water bath at a higher temperature between about 25° C. to about 100° C. (preferably from about 80° C. to about 86° C.; then removing the water from the membrane at a drying temperature that can range from about 20° C. to 150° C. (preferably from about 65° C. to 70° C.) and finishing by coating the surface of the asymmetric membrane with a thermally curable or UV curable polysiloxane or other suitable coating.
[0014] The following examples are provided to illustrate one or more preferred embodiments of the invention, but are not limited embodiments thereof. Numerous variations can be made to the following examples that lie within the scope of the invention.
EXAMPLE 1
A Cellulose Diacetate (Ca) & Cellulose Triacetate (CTA) Asymmetric Membrane
[0015] A cellulose acetate/cellulose tracetate asymmetric membrane was prepared from a casting dope comprising, by approximate weight percentages, 8% cellulose triacetate, 8% cellulose diacetate, 32% 1,3 dioxolane, 12% NMP, 24% acetone, 12% methanol, 2% maleic acid and 3% n-decane. A film was cast on a nylon web, then gelled by immersion in a 0° C. water bath for about 10 minutes, and then annealed in a hot water bath at 86° C. for 10-15 minutes. The resulting wet membrane was dried at a temperature between 65 to 70° C. to remove water. The dry asymmetric cellulosic membrane was coated with an epoxy silicone solution containing 8 wt-% epoxy silicone solution. The silicone solvent contained a 1:3 ratio of hexane to heptane. The epoxy silicone coating was exposed to a UV source for a period of about 2 to 4 minutes at ambient temperature to cure the coating while the silicone solvent evaporated to produce the epoxy silicone coated membrane of the present invention.
[0016] The epoxy silicone coated membranes were evaluated for gas transport properties using a feed gas containing 10 vol-% CO 2 and 90 vol-% CH 4 at a feed pressure of 6.89 MPa (1000 psig) and 50° C. Table 1 shows a comparison of the CO 2 permeability and the selectivity (α) of the dense film (intrinsic properties) and the asymmetric membrane performances.
[0000]
TABLE 1
Gas Transport Properties
CO 2 /CH 4
Membrane
CO 2
Selectivity
Dense film
7.2 Barrers*
21.9
Asymmetric membrane
136 (GPU**)
17.3
*Barrer = 10 −10 cm 3 (STP)cm/sec · cm 3 · cmHg
**Gas Permeation Unit (GPU) = 10 −6 cm 3 (STP)/cm 2 sec · cmHg
EXAMPLE 2
Matrimid/Polyethersulfone Blended Asymmetric Membrane
[0017] A Matrimid polyimide/polyethersulfone blended asymmetric membrane was prepared from a casting dope comprising, by approximate weight percentages, 6.7% polyethersulfone, 11.8% Matrimid, 46.7% 1,3 dioxolane, 23.4% NMP, 5.8% acetone, and 5.8% methanol. A film was cast on a non-woven web then gelled by immersion in a 0° C. water bath for about 10 minutes, and then annealed in a hot water bath at 86° C. for 10-15 minutes. The resulting wet membrane was dried in at a temperature between 65 to 70° C. to remove water. The dry asymmetric membrane was coated with an epoxy silicone solution containing 8 wt-% epoxy silicone solution. The silicone solvent comprised a 1:3 ratio of hexane to heptane. The epoxy silicone coating was exposed to a UV source for a period of 2 to 4 minutes at ambient temperature to cure the coating while the silicone solvent evaporated to produce the epoxy silicone coated membrane of the present invention.
[0018] The epoxy silicone coated membranes were evaluated for gas transport properties using a feed gas containing 10 vol-% CO 2 , 90 vol-% CH 4 at a feed pressure of 6.89 MPa (1000 psig) and 50° C. Table 2 shows a comparison of the CO 2 permeability and the selectivity (α) of the dense film (intrinsic properties) and the asymmetric membrane performances.
[0000]
TABLE 2
Gas Transport Properties
CO 2 /CH 4
Membrane
CO 2
Selectivity
Dense film
7.2 Barrers*
25.1*
Asymmetric membrane
110 GPU
24.6
*Dense film was tested at 690 kPa (100 psig), 50° C. and pure gas
EXAMPLE 3
P84 Polyimide/Polyethersulfone Blended Asymmetric Membrane
[0019] A P84 polyimide/polyethersulfone blended asymmetric membrane was prepared in from a casting dope comprising, by approximate weight percentages, 6.5% polyethersulfone, 12.2% P84 polyimide, 50.5% 1,3 dioxolane, 24.3% NMP, 3.7% acetone, and 2.8% methanol. A film was cast on a non-woven web, then gelled by immersion in a 0° C. water bath for about 10 minutes, and then annealed in a hot water bath at 86° C. for 10-15 minutes. The resulting wet membrane was dried at a temperature between 65 to 70° C. to remove water. The dry asymmetric membrane was coated with an epoxy silicone solution containing 8 wt-% epoxy silicone solution. The silicone solvent comprised a 1:3 ratio of hexane to heptane. The epoxy silicone coating was exposed to a UV source for a period of 2 to 4 minutes at ambient temperature to cure the coating while the silicone solvent evaporated to produce the epoxy silicone coated membrane of the present invention.
[0020] The epoxy silicone coated membranes were evaluated for gas transport properties using a feed gas containing 10 vol-% CO 2 , 90 vol-% CH 4 at a feed pressure of 6.89 MPa (1000 psig) and 50° C. Table 3 shows a comparison of the CO 2 permeability and the selectivity (α) of the dense film (intrinsic properties) and the asymmetric membrane performances.
[0000]
TABLE 3
Gas Transport Properties
CO 2 /CH 4
Membrane
CO 2
Selectivity
Dense film
2.7 Barrers*
33.7*
Asymmetric membrane
39 GPU
29.2
*Dense film was tested at 690 kPa (100 psig), 50° C. and pure gas
EXAMPLE 4
P84HT Polyimide/Polyethersulfone Blended Asymmetric Membrane
[0021] A P84HT polyimide/polyethersulfone blended asymmetric membrane was prepared from a casting dope comprising, by approximate weight percentages, 6.4% polyethersulfone, 11.8% P84 polyimide, 49% 1,3 dioxolane, 24% NMP, 6.4% acetone, and 2.7% methanol. A film was cast on a non-woven web then gelled by immersion in a 0° C. water bath for about 10 minutes, and then annealed in a hot water bath at 86° C. for 10-15 minutes. The resulting wet membrane was dried in at a temperature between 65 to 70° C. to remove water. The dry asymmetric membrane was coated with an epoxy silicone solution containing 8 wt-% epoxy silicone solution. The silicone solvent comprised a 1:3 ratio of hexane to heptane. The epoxy silicone coating was exposed to a UV source for a period of 2 to 4 minutes at ambient temperature to cure the coating while the silicone solvent evaporated to produce the epoxy silicone coated membrane of the present invention.
[0022] The epoxy silicone coated membranes were evaluated for gas transport properties using a feed gas containing 10 vol-% CO 2 , 90 vol-% CH 4 at a feed pressure of 6.89 MPa (1000 psig) and 50° C. Table 4 shows a comparison of the CO 2 permeability and the selectivity (α) of the dense film (intrinsic properties) and the asymmetric membrane performances.
[0000]
TABLE 4
Gas Transport Properties
CO 2 /CH 4
Membrane
CO 2
Selectivity
Dense film
3.8 Barrers*
32.5*
Asymmetric membrane
25 GPU
30.0
*Dense film was tested at 690 kPa (100 psig), 50° C. and pure gas
EXAMPLE 5
Ultem-1000 Polyetherimide Asymmetric Membrane
[0023] The Ultem-1000 polyetherimide asymmetric membrane was prepared from a casting dope comprising, by approximate weight percentages, 21% Ultem-1000, 55% 1,3 dioxolane, 19% NMP, 3% acetone, and 2% methanol. A film was cast on a non-woven web then gelled by immersion in a 0° C. water bath for about 10 minutes, and then annealed in a hot water bath at 86° C. for 10-15 minutes. The resulting wet membrane was dried in at a temperature between 65 to 70° C. to remove water. The dry asymmetric membrane was coated with an epoxy silicone solution containing 8 wt-% epoxy silicone solution. The silicone solvent comprised a 1:3 ratio of hexane to heptane. The epoxy silicone coating was exposed to a UV source for a period of 2 to 4 minutes at ambient temperature to cure the coating while the silicone solvent evaporated to produce the epoxy silicone coated membrane of the present invention.
[0024] The epoxy silicone coated membranes were evaluated for gas transport properties using a feed gas containing 10 vol-% CO 2 , 90 vol-% CH 4 at a feed pressure of 6.89 MPa (1000 psig) and 50° C. Table 5 shows a comparison of the CO 2 permeability and the selectivity (α) of the dense film (intrinsic properties) and the asymmetric membrane performances.
[0000]
TABLE 5
Gas Transport Properties
CO 2 /CH 4
Membrane
CO 2
Selectivity
Dense film
1.95 Barrers*
30.3*
Asymmetric membrane
28.5 GPU
21.5
*Dense film was tested at 690 kPa (100 psig), 50° C. and pure gas
EXAMPLE 6
Matrimid Polyimide Asymmetric Membrane
[0025] The Matrimid asymmetric membrane was prepared in a conventional manner from a casting dope comprising, by approximate weight percentages, 17% Matrimid, 51% 1,3 dioxolane, 20% NMP, 6% acetone, 6% methanol. A film was cast on a non-woven web then gelled by immersion in a 0° C. water bath for about 10 minutes, and then annealed in a hot water bath at 86° C. for 10-15 minutes. The resulting wet membrane was dried in at a temperature between 65 to 70° C. to remove water. The dry asymmetric membrane was coated with an epoxy silicone solution containing 8 wt-% epoxy silicone solution. The silicone solvent comprised a 1:3 ratio of hexane to heptane. The epoxy silicone coating was exposed to a UV source for a period of 2 to 4 minutes at ambient temperature to cure the coating while the silicone solvent evaporated to produce the epoxy silicone coated membrane of the present invention.
[0026] The epoxy silicone coated membranes were evaluated for gas transport properties using a feed gas containing 10 vol-% CO 2 , 90 vol-% CH 4 at a feed pressure of 6.89 MPa (1000 psig) and 50° C. Table 6 shows a comparison of the CO 2 permeability and the selectivity (α) of the dense film (intrinsic properties) and the asymmetric membrane performances.
[0000]
TABLE 6
Gas Transport Properties
CO 2 /CH 4
Membrane
CO 2
Selectivity
Dense film
10.0 Barrers*
28.2*
Asymmetric membrane
140 GPU
20.0
*Dense film was tested at 690 kPa (100 psig), 50° C. and pure gas
EXAMPLE 7
P84 Polyimide Asymmetric Membrane
[0027] The P84 asymmetric membrane was prepared in a conventional manner from a casting dope comprising, by approximate weight percentages, 18.7% P84, 50.5% 1,3 dioxolane, 24.3% NMP, 3.7% acetone, and 2.8% methanol. A film was cast on a non-woven web then gelled by immersion in a 0° C. water bath for about 10 minutes, and then annealed in a hot water bath at 86° C. for 10-15 minutes. The resulting wet membrane was dried in at a temperature between 65 to 70° C. to remove water. The dry asymmetric membrane was coated with an epoxy silicone solution containing 8 wt-% epoxy silicone solution. The silicone solvent comprised a 1:3 ratio of hexane to heptane. The epoxy silicone coating was exposed to a UV source for a period of 2 to 4 minutes at ambient temperature to cure the coating while the silicone solvent evaporated to produce the epoxy silicone coated membrane of the present invention.
[0028] The epoxy silicone coated membranes were evaluated for gas transport properties using a feed gas containing 10 vol-% CO 2 , 90 vol-% CH 4 at a feed pressure of 6.89 MPa (1000 psig) and 50° C. Table 7 shows a comparison of the CO 2 permeability and the selectivity (α) of the dense film (intrinsic properties) and the asymmetric membrane performances.
[0000]
TABLE 7
Gas Transport Properties
CO 2
CO 2 /CH 4
Membrane
Permeance
Selectivity
Dense film
3.0 Barrers*
28.0*
Asymmetric membrane
8.7 GPU
28.0
*Dense film was tested at 690 kPa (100 psig), 50° C. and pure gas
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This invention relates to a method of making flat sheet asymmetric membranes, including cellulose diacetate/cellulose triacetate blended membranes, polyimide membranes, and polyimide/polyethersulfone blended membranes by formulating the polymer or the blended polymers dopes in a dual solvent mixture containing 1,3 dioxolane and a second solvent, such as N,N′-methylpyrrolidinone (NMP). The dopes are tailored to be closed to the point of phase separation with or without suitable non-solvent additives such as methanol, acetone, decane or a mixture of these non-solvents. The flat sheet asymmetric membranes are cast by the phase inversion processes using water as the coagulation bath and annealing bath. The dried membranes are coated with UV curable silicone rubber. The resulting asymmetric membranes exhibit excellent permeability and selectivity compared to the intrinsic dense film performances.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. patent application Ser. No. 14/054,790 filed on Oct. 15, 2013. The entire contents of U.S. patent application Ser. No. 14/054,790 are hereby incorporated by reference.
BACKGROUND
The present disclosure relates to a device for mounting equipment, such as solar panels and other equipment, to tile roofs.
Mounting solar panels, such as solar photovoltaic (PV) panels or solar thermal panels, to tile roofs present its own particular set of challenges. Roof tile can be made of a variety of materials such as ceramic, slate, concrete, or clay. These materials can be brittle and therefore do not present a stable mounting surface for solar panels or other roof mounted equipment as it goes through the normal stress of wind and weather. In addition, roof tiles come in a variety of different shapes and styles, for example, flat roof tile, or curved barrel tile. This variation in shape and style also presents challenges for mounting equipment.
One solution has been to use a mounting device that includes a base portion in combination with a hook or bracket member. A portion of roof tile is removed to expose the roof sheeting. The base engages and secures the mounting device to the exposed roof directly. The hook or bracket member engages the equipment racking system to the mounting device. Flashing is generally placed on top of the base to prevent water infiltration. The removed tile portion is then re-secured over the base with the top tab of bracket member exposed above the tile to allow equipment or mounting hardware to be attached.
One of the challenges with this arrangement is the position of the base is often dictated by the rafters below the roof sheeting and therefore limits the position of roof equipment racking with respect to the roof tile peaks and valleys and the postion of the mounting device.
SUMMARY
The present disclosure describes a device that helps to overcome the challenges of mounting solar panels and other equipment to tile roofs presented in the Background section of this disclosure. In one aspect, the present disclosure describes a mounting device for mounting equipment to a tile roof where the mounting device can be constrained to adjust in discreet steps in two directions and continuously in a third direction after the device is mounted to a tile roof. This allows, for example, an equipment-mounting portion of the mounting device, to be adjusted in three directions relative where the device is attached to the tile roof. This simplifies installation because it allows flexibility in the placement of the equipment racking system relative to mounting device. For example, the mounting device can still be placed so it engages the rafters, as described in the background, but the racking system position is not solely determined by the position of the mounting device as there is some degree of flexibility. The two discrete step adjustments can be along the direction of maximum stress as compared with the continuous step adjustment. This helps assure minimum slippage in the directions of most stress while allowing for a more flexible adjustment along the line of less stress.
In another aspect, the present disclosure describes a mounting device for mounting equipment to a tile roof that includes a base, a bracket, and an equipment mounting extension. The base includes an upward projected channel with stepped grooves on the inside of the channel and a complementary pair of longitudinal slots along the length of each side of the channel. The bracket includes a first bracket portion and second bracket portion projecting away from the vertex edge of the bracket. The first bracket portion includes complementary stepped grooves and a slot transverse to its width that engages the channel and longitudinal slot of the upward projected channel. The transverse slot is aligned with the complementary pair of longitudinal slots and joined by a fastener, such as a complementary nut and bolt. When the fastener is engaged but loose, the bracket can be adjusted continuously along the longitudinal slot and in discrete steps up and down the height of the upward projected channel.
The second bracket portion includes a U-channel projecting away from the end distal to the vertex edge, and parallel to the plane of the second portion top surface. The U-channel includes toothed inner surfaces with the teeth, or steps, running transverse to the length of the second bracket portion or parallel to the vertex edge defining the width of the second bracket portion.
In a further aspect, the toothed inner surfaces of the U-channel are configured to adjustably engage toothed outer surfaces of an equipment mounting extension. In this configuration the equipment-mounting portion acts as an adjustable extension of the second bracket portion. The equipment mounting extension includes an equipment-mounting portion. This can include a slot or an aperture for engaging equipment or can be in the form of an angle bracket, L-bracket, C-bracket, or hook shaped.
This Summary introduced a selection of concepts in simplified form relating to a novel device for mounting equipment to tile roofs. The novel device for mounting equipment to tile roofs is described in further detail in the Description. The Summary is not intended to identify essential features or limit the scope of the claimed subject matter.
DRAWINGS
FIG. 1 shows in partially explode perspective view, a solar panel system and tile roof structure with a device for mounting solar panels and other equipment to the tile roof.
FIG. 2 shows in detail perspective view, the device for mounting solar panels and other equipment to the tile roof of FIG. 1 , with an upper tile removed to expose a mounting plate.
FIG. 3 shows, in exploded perspective view, the device of FIG. 1 .
FIG. 4 shows a perspective view of the device of FIG. 1
FIG. 5 shows a side view of the device of FIG. 1
FIG. 6 shows a front view of the device of FIG. 1 .
FIG. 7 shows a top view of the device of FIG. 1
FIG. 8 shows a sectional view of the device of FIG. 1 taken along section lines 8 - 8 of FIG. 7 .
FIG. 9 shows in perspective view the device of FIG. 1 with an alternatively equipment mounting portion.
FIG. 10 shows a side view of the device of FIG. 9 .
FIG. 11 shows an exploded perspective view of an alternative solar panel system and tile roof structure with a device for mounting solar panels and other equipment to the tile roof.
FIG. 12 shows a front and top perspective view of the device of FIG. 11 .
FIG. 13 shows a back and top perspective view of the device of FIG. 11 .
FIG. 14 shows a side view of the device of FIG. 11 .
FIG. 15 shows a front elevation view of the device of FIG. 11 .
FIG. 16 shows a top plan view of the device of FIG. 11 .
FIG. 17 shows a sectional view of the device of FIG. 16 taken along section lines 17 - 17 .
FIG. 18 shows an exploded perspective view of an additional alternative solar panel system and tile roof structure with a device for mounting solar panels and other equipment to the tile roof utilizing the base portion similar to the base portion of FIG. 12 and the equipment mounting bracket similar to the equipment mounting portion of FIG. 3 .
FIG. 19 shows a top and front perspective view of the device of FIG. 18 .
FIG. 20 shows a side view of the device of FIG. 18 .
DESCRIPTION
The following description is made with reference to figures, where like numerals refer to like elements throughout the several views, FIG. 1 shows in partially explode perspective view, a solar panel system and tile roof structure 10 with a mounting device 15 for mounting one or more solar panels 11 and other equipment to the tile roof 13 . Solar panels 11 are secured to rails 17 by solar panel end-clamps 19 and solar panel mid-clamps 21 . The rails 17 are secured the mounting device 15 . The mounting device 15 is secured to the tile roof 13 under the roofing tiles 23 .
To aid in understanding the mounting device 15 in relation to the tile roof 13 and the rails 17 , FIG. 2 shows the mounting device 15 mounted on roof sheeting 25 with roofing tiles 23 removed to expose the mounting device 15 structure. The roof sheeting 25 is typically plywood or tarpaper underlayment over plywood, but can be any material suitable for covering a roof. The mounting device 15 includes a base 27 , an angled bracket 29 , and an equipment-mounting extension 31 . The base 27 is shown mounted to the roof sheeting 25 by wood securing fasteners 33 , such as a wood screw or lag bolt, through apertures 35 in the base 27 . The base 27 includes a base portion channel 37 projecting upward from the plane of the base 27 . One end of the angled bracket 29 is secured to the base portion channel 37 . The equipment-mounting extension 31 is secured to the other end of the angled bracket 29 . The equipment-mounting extension 31 also secures the rail 17 to the mounting device 15 and thereby the roof sheeting 25 . To install the mounting device 15 , a portion of the roofing tiles 23 are removed, exposing the roof sheeting 25 , so that the base 27 can be secured to the roof sheeting 25 directly. Depending on the style of tile roof 13 , a portion of the roofing tile 23 may be cut in order to create a space to place both the angled bracket 29 and the equipment-mounting extension 31 , as illustrated.
FIG. 3 shows, in exploded perspective view, the mounting device 15 . Illustrated are the base 27 , the angled bracket 29 , and the equipment-mounting extension 31 , the wood securing fasteners 33 and a gasket 39 . The gasket 39 , which is optional, mounts between the base 27 and the roof sheeting. The gasket 39 includes apertures 35 for passing through the body of the wood securing fasteners 33 . The apertures 35 are similar in size and location as the apertures 35 of the base 27 .
The base 27 is shown with the base portion channel 37 projecting upward from the mounting plane of the base 27 . While the base portion channel 37 is shown projecting perpendicularly upward, the base portion channel 37 can project upward at other angles, as required. The base portion channel 37 includes toothed inner surfaces 41 . The teeth or steps run longitudinally along the base portion channel 37 and are approximately parallel to the mounting plane of the base 27 .
The angled bracket 29 includes a first bracket portion 43 and a second bracket portion 45 . The first bracket portion 43 includes toothed outer surfaces 47 . The teeth, or steps, run along the width of the angled bracket 29 and parallel to the vertex edge of the angled bracket 29 . These toothed outer surfaces 47 of the first bracket portion 43 of the angled bracket 29 are configured to engage with the toothed inner surfaces 41 of the base portion channel 37 . The angled bracket 29 can be a right angle L-bracket. Alternatively, the angle between the first bracket portion 43 and the second bracket portion 45 can be, for example, between approximately 80-degrees and 100-degrees as required by the installation.
The base portion channel 37 includes a first and second opposing slots 49 approximately parallel to the bottom edge of and on opposing surfaces of the base portion channel 37 . The first bracket portion 43 of the angled bracket 29 includes a third slot 51 ; the third slot 51 being transverse to width or longitudinal along the length of the angled bracket 29 . The toothed outer surfaces 47 of the first bracket portion 43 engages toothed inner surfaces 41 of the base portion channel 37 so that the first and second opposing slots 49 and third slot 51 cross at approximately a right angle. The first and second opposing slots 49 and third slot 51 are secured with a machine-threaded fastener 53 and a nut 55 with complementary threading to the machine-threaded fastener 53 . The first and second opposing slots 49 and third slot 51 are positioned so that when the machine-threaded fastener 53 and nut 55 are secured but loose, the angled bracket 29 can be adjusted continuously laterally along the length of the base portion channel 37 , captive in the toothed inner surfaces 41 and can be adjusted in discrete steps along the height of the base portion channel 37 , each step defined by the toothed inner surfaces 41 .
The second bracket portion 45 includes a slotted or hollowed end portion forming a U-channel portion 57 . The U-channel portion 57 includes toothed inner surfaces. The equipment-mounting extension 31 includes a first equipment-mounting extension portion 59 with toothed outer surfaces 61 that are configured to engage the toothed inner surfaces of the U-channel portion 57 . The teeth, or steps, run transverse to the length of the first equipment-mounting extension portion 59 . The U-channel portion 57 includes an aperture 35 sized to pass through a machine-threaded fastener 62 and engage a fourth slot 63 in the equipment-mounting extension 31 . The machine-threaded fastener 62 is secured to a threaded portion 65 in the bottom of the U-channel portion 57 . The machine-threaded fastener is shown as a countersunk screw with a hex-head but is not limited as such. For example, the machine-threaded fastener 62 can be a non-countersunk bolt. The machine-threaded fastener 62 can alternatively be a slot-head, Philips, or torx-head screw, for example.
The equipment-mounting extension 31 includes a second equipment-mounting extension portion 67 or in the form of an equipment mounting portion. The second equipment-mounting extension portion 67 and the first equipment-mounting extension portion 59 together form an angled bracket. The second equipment-mounting extension portion 67 includes slot 69 , or alternatively an aperture, for securing the mounting device. Referring back to FIG. 2 , the equipment-mounting extension 31 is secured to the rail 17 by a machine-threaded fastener 53 and a nut 55 through the slot 69 .
FIG. 4 shows the mounting device 15 in assembled perspective view. FIG. 5 shows the mounting device 15 in side view. FIG. 6 shows the mounting device 15 showing the base portion channel 37 in relation to the base 27 as well as the first and second opposing slots 49 in relation to the base portion channel 37 in front view. FIG. 7 shows a top view of the mounting device 15 showing the base 27 and the base portion channel 37 , in relation to the angled bracket 29 and equipment-mounting extension 31 . FIG. 8 shows a sectional view of the mounting device 15 taken along section lines 8 - 8 of FIG. 7 . Referring to FIG. 7 , the base portion channel 37 is shown offset in relation to the centerline of the base 27 . This is done in order to provide a larger fastening surface in order to offset the forces or rotational torque applied to the equipment-mounting extension 31 applied by the solar panels, rails, and other roof mounted equipment. The position of the base portion channel 37 can be adjusted or centered, as desired, in order to accommodate different designs of the equipment-mounting extension 31 .
FIGS. 4-5 , and 8 show the angled bracket 29 secured to the base 27 with the first bracket portion 43 of the angled bracket 29 engaged with the base portion channel 37 and is secured by the machine-threaded fastener 53 and the nut 55 . The wood securing fasteners 33 are shown with their threaded portions passing through the planar portion of the base 27 and with their heads seated against the planar portion of the base 27 .
In FIG. 5 , the base portion channel 37 is shown with toothed inner surfaces 41 , in side view, engaging the toothed outer surfaces 47 of the first bracket portion 43 . In FIG. 4 , the first and second opposing slots 49 are shown allowing the angled bracket 29 to slide laterally along the toothed inner surfaces 41 .
Referring again to FIGS. 4-5 and 8 , the second bracket portion 45 of the angled bracket 29 , is shown with the U-channel portion 57 with toothed channels transverse to the length of the second bracket portion 45 . The U-channel portion 57 is shown engaged with the toothed outer surfaces 61 of equipment-mounting extension 31 and secured with the machine-threaded fastener 53 into the threaded portion 65 of the bottom of the U-channel portion 57 .
FIG. 9 shows in perspective view the mounting device 15 with an alternatively equipment mounting portion folded over the first equipment-mounting extension portion 59 of the equipment-mounting extension 31 . FIG. 10 shows a side view of the mounting device 15 of FIG. 9 . In FIGS. 9 and 10 , the equipment-mounting extension 31 includes an equipment-mounting end portion 71 the projects upward and then inward creating an inverted L-shape or hook shape with respect to the first equipment-mounting extension portion 59 of the equipment-mounting extension 31 . In FIG. 9 , the equipment-mounting end portion 71 includes a slot 69 or alternatively, a circular aperture, for mounting equipment. In FIGS. 9 and 10 , the equipment-mounting extension 31 , angled bracket 29 and base 27 are shown in approximately the same relationship as described for FIGS. 1-8 .
FIGS. 11-17 show another example of a device 115 for mounting solar panels and other equipment to tile roof in accordance with the present disclosure. FIG. 11 a front exploded perspective view, FIG. 12 shows a front and top perspective view, FIG. 13 shows a back and top perspective view, FIG. 14 shows a side view, FIG. 15 shows a front elevation view, and FIG. 16 shows a top plan view of the device 115 . FIG. 17 shows a sectional view of the device 115 of FIG. 16 taken along section lines 17 - 17 . Referring to FIGS. 11-17 , illustrated are the base 127 , an angled bracket 129 , wood securing fasteners 33 . FIG. 11 illustrates a gasket 139 , which is optional, that mounts between the base 127 and the roof sheeting. The gasket 139 includes apertures 35 for passing through the body of the wood securing fasteners 33 . The apertures 35 are similar in size and location as the apertures 35 of the base 127 .
Referring again to FIGS. 11-17 , the base 127 is shown with the base portion channel 137 projecting upward from the mounting plane of the base 127 . The base portion channel 137 is shown projecting upward at an obtuse angle with respect to the central portion of the base 127 . Typically, the base portion channel 137 can be angled to project upward from 90 degrees to 135 degrees with respect to the base 127 . The base portion channel 137 can project upward at other angles, as required and is not limited to the range given above. The angle is generally limited by the how much torque the wood securing fasteners 33 that secure the base 127 to the roof sheeting can tolerate before the joint between the roof sheet and base fails. The torque is produced by force being applied to the angled bracket 129 by the solar panels and other roof top mounting equipment. While steeper angles allow for more flexible in mounting distance of the equipment with respect to the base 127 , the steeper angle will create more stress on the wood securing fasteners 33 .
Referring to FIGS. 11-14 , and 17 , the base portion channel 137 includes toothed inner surfaces 141 . The teeth or steps run longitudinally along the base portion channel 137 and are approximately parallel to the mounting plane of the base 127 . The angled bracket 129 includes a first bracket portion 143 and a second bracket portion 145 . The first bracket portion 143 includes toothed outer surfaces 147 . The teeth, or steps, run along the width of the angled bracket 129 and parallel to an outside vertex edge 148 of the angled bracket 129 . These toothed outer surfaces 147 of the first bracket portion 143 of the angled bracket 129 are configured to engage with the toothed inner surfaces 141 of the base portion channel 137 . The angled bracket 129 is typically angled so that second bracket portion 145 , when engaged with the base portion channel 137 is typically 0 to 10 degrees with respect to the horizon or plane of the roof sheeting. In this typical scenario, for a base portion channel 137 with an angle with respect to the plane of the base of 110-degrees, the inside angle between the first bracket portion 143 and the second bracket portion 145 would be 110-degrees+0 to 10 degrees=110 to 120 degrees. For a base portion channel 137 of 100-degrees, for the second bracket portion 145 to make an angle with the horizon of 0 to 10 degrees, the angle between the first bracket portion 143 and the second bracket portion 145 would be between 100 to 110-degrees. The reader should note that these examples are meant to clarify. The claimed invention is not limited only to these angles or to the ranges given. Other angles can be selected depending on factors such as the roof tile length and the height of the roof tile above the roof sheeting as well as the stress factors mentioned in the preceding paragraphs.
The base portion channel 137 includes a first slot 149 shown in FIGS. 11 , 12 , 15 , and 16 , and second slot 150 shown in FIGS. 11-14 and 17 , the first slot 149 and the second slot 150 on opposing surfaces of the base portion channel 137 and approximately parallel to the bottom edge of the base portion channel 137 . As shown in FIG. 11 , the first bracket portion 143 of the angled bracket 129 includes a third slot 151 ; the third slot 151 being transverse to width or longitudinal along the length of the angled bracket 129 . The toothed outer surfaces 147 of the first bracket portion 143 engages toothed inner surfaces 141 of the base portion channel 137 so that the first slot 149 , the second slot 150 , and third slot 151 cross at approximately a right angle. The first slot 149 , the second slot 150 , and the third slot 151 are secured with a machine-threaded fastener 53 into threading 152 along the inside surface of the second slot 150 . Alternatively, the machine-threaded fastener 53 can engage a nut as described for FIG. 3 . The first slot 149 , the second slot 150 , and the third slot 151 are positioned so that the angled bracket 129 can be adjusted continuously laterally along the length of the base portion channel 137 , captive in the toothed inner surfaces 141 and can be adjusted in discrete steps along the height of the base portion channel 137 , each step defined by the toothed inner surfaces 141 .
In FIGS. 11-17 , the angled bracket 129 is illustrated including a third bracket portion 167 projecting upward from the second bracket portion 145 . The third bracket portion 167 and the second bracket portion 145 together form an angled bracket. In FIGS. 12 , 13 , and 15 , the third bracket portion 167 includes a fourth slot 169 , or alternatively an aperture, for securing the mounting device to the rail or other equipment. The fourth slot is shown in FIGS. 11-13 , and 15 .
FIG. 18 shows an exploded perspective view of an additional alternative solar panel system and tile roof structure with a device 215 for mounting solar panels and other equipment to the tile roof utilizing the base 127 similar to the base 127 of FIG. 12 , and the equipment-mounting extension 31 similar to the equipment-mounting extension 31 of FIG. 3 . FIG. 19 shows a top and front perspective view, and FIG. 20 shows a side view of the device 215 of FIG. 18 . Referring to FIGS. 18-20 , illustrated are the base 127 , an angled bracket 229 , the equipment-mounting extension 31 , wood securing fasteners 33 , and machine-threaded fastener 53 . FIG. 18 illustrates a gasket 139 , which is optional, that mounts between the base 127 and the roof sheeting. The gasket 139 includes apertures 35 for passing through the body of the wood securing fasteners 33 . The apertures 35 are similar in size and location as the apertures 35 of the base 127 .
Referring again to FIGS. 18-20 , the base 127 is shown with the base portion channel 137 projecting upward from the mounting plane of the base 127 . The base portion channel 137 is shown projecting upward at an obtuse angle with respect to the center of the base 127 , and can project upward at a range of angles, as previously described for FIG. 11 .
The base portion channel 137 includes toothed inner surfaces 141 . The teeth or steps run longitudinally along the base portion channel 137 and are approximately parallel to the mounting plane of the base 127 . The angled bracket 229 includes a first bracket portion 243 and a second bracket portion 245 . Referring to FIG. 18 , the first bracket portion 143 includes toothed outer surfaces 247 . The teeth, or steps, run along the width of the angled bracket 229 and parallel to the outside vertex edge 148 of the angled bracket 229 . These toothed outer surfaces 247 of the first bracket portion 243 of the angled bracket 229 are configured to engage with the toothed inner surfaces 141 of the base portion channel 137 . The angled bracket 129 is typically angled so that second bracket portion 145 , when engaged with the base portion channel 137 is typically 3 to 8 degrees with respect to the horizon or plane of the roof sheeting can be angled with respect to the horizon, or the alternatively, the plane of the roof sheeting, as described for FIGS. 11-17 .
The base portion channel 137 includes the first slot 149 shown in FIGS. 18-19 , and the second slot 150 shown in FIGS. 18-20 , the first slot 149 and the second slot 150 on opposing surfaces of the base portion channel 137 and approximately parallel to the bottom edge of the base portion channel 137 . As shown in FIG. 18 , the first bracket portion 243 of the angled bracket 229 includes a third slot 251 ; the third slot 251 being transverse to width or longitudinal along the length of the angled bracket 229 . The toothed outer surfaces 247 of the first bracket portion 243 engages toothed inner surfaces 141 of the base portion channel 137 so that the first slot 149 , the second slot 150 , and third slot 251 cross at approximately a right angle. The first slot 149 , the second slot 150 , and the third slot 251 are secured with a machine-threaded fastener 53 into threading along the inside surface of the second slot 150 . Alternatively, the machine-threaded fastener 53 can engage a nut as described for FIG. 3 . The first slot 149 , the second slot 150 , and the third slot 251 are positioned so that the angled bracket 229 can be adjusted continuously laterally along the length of the base portion channel 137 , captive in the toothed inner surfaces 141 and can be adjusted in discrete steps along the height of the base portion channel 137 , each step defined by the toothed inner surfaces 141 .
Continuing to refer to FIG. 18 , the second bracket portion 245 includes a slotted or hollowed end portion forming a U-channel portion 257 . The U-channel portion 257 includes toothed inner surfaces. The equipment-mounting extension 31 , is as previously described for FIG. 3 , and includes a first equipment-mounting extension portion 59 with toothed outer surfaces 61 that are configured to engage the toothed inner surfaces of the U-channel portion 257 of the angled bracket 229 . The teeth, or steps, run transverse to the length of the first equipment-mounting extension portion 59 . The U-channel portion 257 includes an aperture 35 sized to pass through a machine-threaded fastener 62 and engage a fourth slot 63 in the equipment-mounting extension 31 . In FIGS. 18-20 , the machine-threaded fastener 62 is secured to a threaded portion 265 in the bottom of the U-channel portion 257 .
In FIG. 18-19 , illustrated is the second equipment-mounting extension portion 67 of the equipment-mounting extension 31 . The second equipment-mounting extension portion 67 and the first equipment-mounting extension portion 59 together form a second angled bracket as previously described for FIG. 3 . The second equipment-mounting extension portion 67 includes slot 69 , or alternatively an aperture, for securing the mounting device. The equipment-mounting extension 31 can be secured to the rail 17 , for example of FIG. 2 , by a machine-threaded fastener 53 and a nut 55 through the slot 69 .
A device for mounting equipment, such as solar panels, to tile roof structures has been described. It is not the intent of this disclosure to limit the claimed invention to the examples, variations, and exemplary embodiments described in the specification. Those skilled in the art will recognize that variations will occur when embodying the claimed invention in specific implementations and environments. For example, it is possible to implement certain features described in separate embodiments in combination within a single embodiment. Similarly, it is possible to implement certain features described in single embodiments either separately or in combination in multiple embodiments. It is the intent of the inventor that these variations fall within the scope of the claimed invention. While the examples, exemplary embodiments, and variations are helpful to those skilled in the art in understanding the claimed invention, it should be understood that, the scope of the claimed invention is defined solely by the following claims and their equivalents.
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Disclosed is a tile roof equipment-mounting device for mounting solar panels and other equipment to tile roofs. The tile roof mount includes a base and an angled bracket. The base can include a base portion channel projecting upward from the base, with stepped grooves, as well as first and second slots running along opposing sides of the base portion channel in a direction parallel to the base. The angled bracket can include complementary stepped grooves that engage the base portion channel. The angled bracket can include a third slot that is perpendicular to the vertex between angled portions of the angled bracket. A threaded fastener can adjustably engage first, second, and third slots. This combination allows the tile roof mount so that the height is vertically discreetly adjustable and horizontally continuously adjustable.
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BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates to the method of providing specific personal indicia that can be bonded to an individual's anatomy.
Applicants are aware of the following patents: U.S. Pat. Nos. 3,952,438; 3,949,233; 4,027,391; 4,208,795; 4,233,964; 4,239,261; 4,473,353; 4,557,693; 4,439,154; 4,512,744 and U.S. Pat. No. Re. 30,594. The disclosures of the listed patents are incorporated by reference herein.
The need for positive identification of people, both living and deceased, has constantly plagued mankind. Some of the many vital needs for identification include criminal investigations and medical emergencies. Positive identification would especially benefit victims of accidents, amnesia, or other similar incapacities. Certain post mortem identification gives peace of mind and finality that sometimes does not exist with current methods in the wake of many tragic events.
Many previous positive identification systems require a complicated insertion process and may require complex electronic detection equipment to read the indicia. Some designs place indicia on or in dental prostheses or on implantable substrates that are difficult and costly to insert and remove and which involve complicated and intrusive procedures to read or retrieve.
The applicants have discovered a new method of preparing and installing personal identification indicia. Applicants' method involves taking personal identifying information and shrinking it onto a microdot through a photolithographic process, for example, using a silver halide process. This provides a simple, inexpensive method of reducing vast quantities of information. The indicia is developed on a substantially chemically inert thermoplastic film, such as a polyolefin. This gives long lasting durability and protection. The indicia is then cut and smoothed at the edges.
The finished microdot is bonded to an individual's anatomy, for example, to the teeth by any standard dental bonding agent. A particular advantage can be obtained by embedding the microdot in the adhesive to encapsulate, and further protect, the entire microdot.
The ease of application of the applicants' process is a major advantage over many current methods. This is because the microdot is smaller, thinner and lighter and because applicants' microdot is much less obtrusive. Applicants' microdot can be attached to any hard portion of an individual's body using common bonding agents. This results in less risk and fewer complications for the individual involved than many of the complicated intrusive processes that are currently used.
The applicants' process also provides for ease of information retrieval. Applicants' microdot may be read by visual observation by simple magnification; this represents a vast improvement over all previous methods, such as complicated extractions or the use of expensive, complex, electronic detection equipment.
The applicants' process of production is also very inexpensive. Not only are the materials that compose the microdot very inexpensive, but the operations are few and simple. The process lends itelf to mass production by permitting use of a high intensity light or laser cutting device to simultaneously cut and polish the microdot edge and create suitable edge characteristics. The viewing of the indicia can be done by simple magnification at the location where it is attached.
Applicants' system permits implementation of positive identification systems on a large scale. Large scale manual and automated information handling systems are possible. For example, by placing a large number of indicia on a single sheet of film, and using a device which cuts and polishes the indicia, a large quantity of indicia, i.e. many microdots, can be prepared in a short time. The applicants' process is vastly superior to any current method in this regard.
Applicants' process and product may be further understood by reference to the following drawings, Description of the Drawings, and Description of the Preferred Embodiments.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow chart of applicants' process.
FIG. 2 is a layout of the indicia prior to photographing.
FIG. 3 is an array of indicia on a film.
FIG. 4 is a side view of individual microdot after cutting and polishing.
FIG. 5 is a schematic of a device for cutting microdots.
FIG. 6 is a layout of the human mouth showing the microdot bonded to a tooth.
FIG. 7 is an exploded view showing a microdot and apparatus to attach the microdot to a tooth surface.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An overview of the entire process is flow charted in FIG. 1. The first step 20 shown is the preparation of the indicia (information), such as in the form 21, shown in FIG. 2. The information to be used and the shape of the indicia must be selected. The second step 22 is the reduction of the size and printing the indicia photographically, for example, using a two step process having a first reduction of 2.2X followed by a second reduction of 42X. A suitable device on which to reduce and print the information is a DOCUMATE II (™), microfilm printer manufactured by Terminal Data Corporation. The DOCUMATE II uses a DMF-8 camera exposing images on 105 mm film using a moving film, fixed lens technique. Other equivalent reduction processes and equipment may be used. After printing, the indicia is cut and edge polished, at step 26, to form a complete microdot 28, as shown in FIG. 4. The reduced image is printed on archival quality laminated silver halide film 29, such as Eastman Kodak AHU-1460 (™) 5 mil film, or equivalent. Preferably a suitable number of separate microdots 28 are printed in an array 30, such as shown in FIG. 3. As shown in FIG. 4, the microdot 28 is a multiple ply film 29 with the silver halide layer 32 between plies 34, 35. The support ply 35 is a suitable polymer film, such as a polyester. A 4 inch by 6 inch (10 cm×15 cm) print will hold a 13×25 array 30 of 325 microdots 28, each about 2 mm in effective diameter and having about 5 mm spacing center to center between adjacent microdots 28, as shown in FIG. 3. Typically a photographic quality within the parameters established for Class I microfiche is satisfactory for applicants' microdot 28. Generally, a grid pattern (array) 30 within the parameters set for Class I and Class II microfiche is satisfactory.
Individual microdots 28 may be cut from the array 30 by micro machining techniques. Applicants have found that the edges 36 of applicants' microdot 28 may be effectively cut and polished by a laser or high intensity light beam cutter 37. For example a Photon E505 (™) 500 watt numerically controlled CO 2 laser, or a Mazak LASER-PATH (™) 500 watt numerically controlled CO 2 laser or a comparable cutting machine can be used to cut applicants' microdot 28. The Photon E505 and the Mazak are conventional numerically controlled CO 2 laser cutting devices operating at a wave length of 10.6 microns. A laser cutting tool is shown schematically in FIG. 5. The beam is preferably collimated to have a taper of less than one degree and will produce a smoothness of cut of about 32 microinches. In cutting, the beam or cut width (kerf) is about 0.1 mm. The diameter of the cut microdot 28 is about 2 mm. The plies 34, 35 of the microdot 28 are fused and edge 36 is polished simultaneously with the cutting. Preferably, the heat creates a heat shrink and thickening of the polymer plies 34, 35 at the edge 36 of the microdot 28, producing a smooth thickened toroidal portion 38. This thickened portion 38 at edge 36 provides a particular advantage when bonding the microdot 28, as described herein. The power for the cut and heat shrink depends to a certain extent on the thickness of film 29 and the properties of the polymer of film 29, as well as on the particular cutting machine 37 used, but is typically about 80-100 watts for a typical photo film 29 having a thickness of about 0.25 mm. A cutting speed of about 10-50 m/min is normally satisfactory for film of this thickness. The beam is typically circular in cross section, but other beam shapes may be used. Fine tuning of the cut can easily be accomplished by adjusting the power level and by controlling the cut speed, as is known in the art.
As shown in FIG. 2, each completed microdot 28 has guide marks 39, formed when cutting the microdot 28 from the format 21. Guide marks 39 permit visual inspection to determine that the orientation of an installed microdot 28 is proper, without using magnification.
After the microdots 28 are cut, they are collected, either by hand or by an automated system, and packaged. Particular care should be taken to avoid contamination of the surface of microdot 28 with oil or dirt. If collection is by hand, for example, it is recommended that white gloves and other "clean room" type handling procedures be used in packaging and transporting finished microdots 28.
The finished microdot 28 is bonded to a hard body surface, for example, to a permanent tooth 40, as shown in FIGS. 6 and 7. Conventional dental adhesives of the self curing and light curing type, for example, may be used. DURAFIL (™) acrylic dental bonding agent has been found to be satisfactory.
The device can be installed on the surface of a permanent tooth 40 by first pumacing the surface of the tooth 40, with flours of pumice and flushing the surface of the tooth with water. The prepared surface is then preferably etched, for example with 35% phosphorous acid liquid or gel for about 60 seconds and then again flushed copiously with water. The tooth 40 is then dried thoroughly and the microdot 28 is bonded to the prepared surface. Primary teeth may require a preliminary abrasion with an abrasive soft disc or dental stone to disrupt the prismatic outer layer of enamel, prior to pumacing.
Typically a discrete drop of an adhesive or bonding material 42, e.g., a conventional acrylic dental bonding agent, is placed on the prepared surface of the tooth 40. The microdot 28 is then placed into the center of the bonding material 42 using forceps or a wand 44, as described herein, the microdot 28 is oriented in proper relationship to the tooth 40 and pressed firmly to the tooth 40. A second drop of bonding material 42 is then placed over the microdot 28, insuring that adequate thickness is achieved over the outer surface and all edges of the microdot 28, to completely encapsulate the microdot 28 in the bonding material 42, as shown in FIG. 7.
Preferably a strippable form 46, such as a Mylar (™) film, is placed over the microdot 28 and adhesive 42 to exclude air from the adhesive 42. If air is permitted to remain in contact with the adhesive 42 while it cures, the outer surface of the adhesive 42 often becomes clouded due to the formation of an air inhibited layer on the surface of the adhesive 42. The use of a strippable form 46 can prevent the formation of the air inhibited layer. On the other hand if the air inhibited layer is formed it may be removed by abrading away a thin layer from the upper surface of the adhesive 42, for example by using a standard fine dental buffing compound.
The use of a strippable form 46 also aids in maintaining a uniform thickness of bonding material 42 over the outer surface of the microdot 28 so that the microdot 28 is completely encapsulated in the adhesive 42. The presence of an acrylic layer completely over the microdot 28 provides a hard, transparent and uniform layer which protects the microdot 28 from scratching, as might occur normally from brushing the teeth. Scratching could interfere with reading the microdot 28. The hard polymer adhesive 42 forms a very hard, smooth and transparent layer which is resistant to scratching and which permits the microdot 28 to be read through the adhesive layer 42. If a form 46 is used, it may be transparent to UV light to permit activation of UV cured adhesives through the form 46. The form 46 may use a backing form 48, such as a shaped plastic, as shown in FIG. 7. Backing form 48 is preferably a transparent plastic, such as acrylic, which permits passage of activating light to initiate curing of light cured bonding agents. Wand 44 is an appliance which may be equipped with a conventional light source, not shown. The light source produces light of a wave length effective to initiate hardening of light cured agents, i.e., ultraviolet light. Once the microdot 28 and bonding agent 44 are in place the cure of the bonding agent can be initiated by activation of the light source. Backing form 48 may e mounted on wand 44 by clips, as shown.
The raised or toroidal edge 36 of the microdot 28 aids in bonding of the microdot 28 to the surface of the tooth 40, by providing additional surface to which the adhesive 42 can attach and by providing contact between the edge of the microdot 28 and the surface of the tooth 40 which permits even distribution of the bonding agent 42 under and around the microdot 28, as shown. It is advantageous to have contact between the edge of microdot 28 and the surface of tooth 40. This provides a smooth transition between the tooth 40 and the microdot 28 which permits an even coverage of the microdot 28 by the bonding agent 42. The smooth transition eliminates sharp edges which may not be fully covered by the bonding agent 42 due to surface tension effects. The surface of the raised toroidal edge 36 is preferably smoothly polished by the laser or light cutting process thus further reducing the effects of surface tension and assisting in producing a uniform coating of bonding agent 42 over the microdot 28. In addition, the raised outer edge 36 allows a film of adhesive 42 to be maintained over the information containing portion of the microdot 28, as shown in FIG. 7, thus protecting the microdot 28 from damage.
The bonded microdot 28 can easily be read, for example by 50X magnification. A variety of small magnifying periscopes, eye pieces, light guides and other devices may be used to view the microdot 28 without the necessity for removing the microdot 28 from the tooth 40 on which it is bonded. It will be appreciated that more complicated devices could be used, if desired, such as light pens, small video cameras or other devices that translate electronic images.
It will be appreciated by those skilled in the art that variations in the invention disclosed herein may be made without departing from the spirit of the invention. The invention is not to be limited to the specific embodiments disclosed herein, but only by the scope of the claims appended hereto.
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A method of producing personal identifying indicia for attaching to a person's body involves preparing a photohalide indicia on a plastic film which is then cut and polished. The method is especially useful to produce photo microdots which may be bonded to a wearer's teeth or other part of the body. The polished edge of the microdot has a smooth enlarged toroidal shape and aids in encapsulating the microdot in a bonding agent to adhere the microdot to a tooth.
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RELATED APPLICATIONS
[0001] This application claims priority of provisional application 61/750,590 filed Jan. 9, 2013. This application is also related to published U.S. Patent Applications 2011/0011722, 2011/0011720, and 2011/0011719, each published Jan. 20, 2011; and to U.S. Patent Publication 2013/0062186, published Mar. 14, 2013, entitled PROCESS FOR TREATING COAL USING MULTIPLE DUAL ZONE STEPS.
[0002] The disclosures of all of the above patent publications and applications are incorporated herein by reference in their entirety. This invention was made with no U.S. Government support and the U.S. Government has no rights in this invention.
TECHNICAL FIELD
[0003] The present invention relates to the field of coal processing, and more specifically to a carbonization process for treating various types of coal for the production of higher value coal-derived products, such as coal char, coal liquids or oils, gaseous fuels, water and heat. More specifically, the present invention relates to processes and apparatus for the more efficient recovery of (1) coal-derived liquids (CDLs) from the gases driven off, and (2) the char produced from coal during pyrolysis. It is applicable to bituminous, sub-bituminous and non-agglomerating lignite ranks of coal.
BACKGROUND OF THE INVENTION
[0004] Coal in its virgin state is sometimes treated to improve its usefulness and thermal energy content. The treatment can include drying the coal and subjecting the coal to a pyrolysis process to drive off low boiling point organic compounds and heavier organic compounds. This thermal treatment of coal, also known as low temperature coal carbonization, causes the release of certain volatile hydrocarbon compounds having value for further refinement into liquid fuels and other coal-derived liquids (CDLs) and chemicals. Subsequently, the volatile components can be removed from the effluent or gases exiting the pyrolysis process. Such thermal or pyrolytic treatment of coal causes it to be transformed into coal char by virtue of the evolution of the coal volatiles and products of organic sulfur decomposition. The magnetic susceptibilities of inorganic sulfur and iron in the resultant char are initiated for subsequent removal of such undesirable components as coal ash, inorganic sulfur and mercury from the coal char.
[0005] It would be advantageous if agglomerating or bituminous coal could be treated in such a manner that would enable volatile components to be effectively removed from the coal at more desirable concentrations, thereby creating a coal char product having reduced organic sulfur and mercury. It would be further advantageous if bituminous coal could be refined in such a manner to create a second revenue stream (i.e., condensable coal liquids), which could be recovered to produce syncrude and other valuable coal products.
[0006] For example, even CDLs collected and separated may contain undesirable particulate matter—as much as 5-10% by weight by some estimates. These small, micron-sized particulates are generally undesirable, particularly if the CDL is to be further processed or refined by additional equipment. Therefore it would be advantageous to remove significant portions of these fine particulates.
SUMMARY OF THE INVENTION
[0007] In a broad aspect, a process for treating coal is described. The process builds on low temperature coal carbonization to separate coal into multiple components, including: coal char, coal-derived liquids (CDLs), and a gaseous fuel also known as syngas. The CDLs are further fractionated into multiple components in some embodiments. For example, in one aspect the invention is a method for treating effluent gases evolved from a coal pyrolysis process, the method comprising:
[0008] passing the evolved gases through at least two distinct condensation zones, each zone being maintained at a different temperature to condense to liquids the different boiling point fractions of the evolved gases;
[0009] (optionally) directing the liquids from each condensation zone to one or more separation units to separate particulate sludge and/or impurities from the condensed liquids; and
[0010] directing the condensed liquids from each separation unit to its own separate storage tank, wherein the temperature of each condensing zone is controlled within a predetermined temperature range to collect a desired CDL fraction in each of the storage tanks.
[0011] In another aspect the invention is a method for treating effluent gases evolved from a coal pyrolysis process, the method comprising:
drying coal to remove moisture; pyrolyzing dried coal in one or more pyrolysis chamber(s) to form coal char and evolved gases; passing the evolved gases through at least two, preferably three or more, distinct condensation zones of an absorber, each zone being maintained at a different temperature to condense to liquids the different boiling point fractions of the evolved gases; optionally directing the liquids from each condensation zone to one or more separation units to separate particulate sludge and/or impurities from the condensed liquids; directing the sludge (and particulates) separated from liquids at each separation unit to a common blending area with the coal char; and directing the condensed liquids from each separation unit to its own separate storage tank, wherein the temperature of each condensing zone is controlled within a predetermined temperature range to collect a desired fraction CDL in each of the storage tanks.
[0018] The methods may include further processing of any of the collected CDL, such as separation or purification by means such as centrifugation, filtration and the like. Particulates and sludge removed from the CDLs in these purification steps may be used in briquetting.
[0019] In other aspects the methods include further processing of the remaining gas stream after CDLs have been removed. For example, a portion of the gas stream may be re-cycled to the pyrolysis chamber(s) for use as a sweep gas to add direct heat. Another portion may be cooled to remove water vapor that remains and is stored as a dried gaseous fuel. Such a dried gaseous fuel has a high heating value, for example greater than 8,000 BTU/lb (20.4 MJ/kg). If being pumped long distances, it may be re-heated, for example to 50-70 C, typically 55-65 C, to reduce the likelihood of any components condensing in the conduits. The proportion for each such use can vary from 0 to 100%.
[0020] In another variation, the gas stream evolved from the absorber may be further processed with an electrostatic precipitator (ESP). The ESP can collect oil mist particles that are entrained in the stream and re-blend them with a light oil CDL fraction.
[0021] In a three zone absorber designed to collect and process CDLs from coal, the temperature set points for the three zones may include sequentially, from about 450 F (232 C) to about 550 F (288 C) for the heavy CDL fraction, from about 250 F (121 C) to about 400 F (204 C) for the middle CDL fraction, and from about 150 F (65 C) to about 250 F (121 C) for the light CDL fraction.
[0022] In another variation, the effluent gases from the pyrolysis process are first passed though a high temperature cyclone to remove char fines, and/or a venturi to mix and nucleate the heaviest condensable CDLs before they are admitted to the absorber. This step increases the capture of the desired CDL fraction in each zone by removal of nucleation sites for mist formation.
[0023] In another variation, any or all of the following fractions may be used as fuel and/or binder to form pellets or briquettes: the coal fines from the cyclone; the bottom bleeds from the highest temperature zone of the absorber; all or a portion of the heavy CDL fraction; all or a portion of the sludge and fines from optional purification of the CDLs.
[0024] Various other embodiments are described herein as well.
[0025] Various advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a generalized process diagram for a pyrolysis or carbonization process with multiple component fractions.
[0027] FIGS. 2A to 2C are sections of a schematic illustration of a process for treating the effluent gases formed by the pyrolysis of various types of bituminous coal.
[0028] FIG. 3 is a chart showing a series of C 6 + hydrocarbon compounds and their equilibrium vapor pressure as a function of temperature.
DETAILED DESCRIPTION OF THE INVENTION
[0029] The process pertains to treating non-agglomerating coal and various types of bituminous coal for the production of coal derived liquid (CDL) and other higher value coal derived products, such as a high calorific value, low volatile, low ash, low sulfur coal, also known as char, suitable for a variety of uses in industry, including metallurgical uses and power production, including forming the char into briquettes.
[0030] FIG. 1 illustrates the process at a very general level. Coal 10 , is heated in one or more drying and/or pyrolysis steps which apply heat as indicated at 12 . As noted above, this process is sometimes referred to as low-temperature carbonization. The pyrolysis process produces three products, water vapor 14 , effluent or evolved gases 16 , and coal char 18 . These three products are cooled which, for gaseous products, leads to some condensation as indicated at 20 . Water vapor 14 is condensed to water 22 , and may be used for further processing steps. While the coal char 18 is one desirable product, the volatile effluent gases 16 from the coal may be refined to create a second revenue stream. The evolved or effluent gases include some gaseous components that will not condense at room temperature and these remain as hydrocarbon gases 24 or syngas, which is a third potential product and revenue stream. However, other components of the effluent gases 16 will condense and are referred to generically as coal-derived liquids or CDLs 26 . According to the invention, CDLs 26 may be further fractionated into multiple components, such as low boiling point light oils 28 , mid boiling point medium weight oils 30 , and high boiling point heavy oils 32 . Finally, the evolved gases may include char fines that may condense as a sludge 34 . This general process is described in more detail below.
[0031] FIG. 2 is a schematic illustration of a process for treating effluent gases 16 evolved from coal that has been pyrolyzed. FIG. 2 is divided into three sections, 2 A, 2 B and 2 C, designed to be viewed as one large schematic. At various points, the lines from one section connect to lines of another section. Furthermore, at several points in the diagram a roman numeral inside a diamond indicates a particular process sampling point or location. These process sampling point locations coincide with those shown in Table B, which give some properties of the process stream at each particular location identified.
[0032] An optional drying step removes excessive moisture from the coal. The dried coal is then fed to a pyrolysis chamber where the coal is pyrolzyed as is known in the art at temperatures typically between about 500-600 C. Multiple pyrolysis stages may be used if desired. The pyrolysis is done with low oxygen and drives off impurities as evolved gases to improve the efficiency of the resulting coal as fuel, a process known as “beneficiation” of the coal.
[0033] Particle carryover in the effluent gas stream exiting from a pyrolysis chamber such as a fluidized bed has been estimated to be as high as about 15-20% by weight. These particles comprise char fines and quinoline insoluble particles. In one known example, these solids amounted to about 16.1% by weight. Consequently, the effluent gas stream may optionally pass through a high temperature, high efficiency cyclone separator 36 which separates out the carbon fine particulates 38. Solid particle loads can be reduced to as little as 1.0% by weight using such separators. Suitable cyclone separators are available from suppliers such as Ducon, 5 Penn Plaza, New York, N.Y.; Fisher-Klosterman, Louisville, Ky.; or Heumann Environmental, Jeffersonville, Ind. For example, some Heurmann units are designed to remove 95% of the minus 5 micron particulates carried in the pyrolysis effluent gas stream. The particulates 38 so removed from the effluent gas stream can be conveyed to a separate collection means or re-injected into the fluidized bed pyrolysis chamber. Preferably, the particulates 38 are transported from the separate collection means to be added downstream to the sludge and subsequently added to the coal char briquetting or shipped with the coal char in bulk form.
[0034] The evolved gases and any remaining particulates escaping the cyclone 36 are fed to the inlet of a variable throat venturi 40 . During the condensation process, pure segmentation in fractionation is hampered by the formation of high boiling point (BP) mist or droplets which serve as nucleation sites, at which lower BP fractions may coalesce prematurely while still at high temperatures. It is desirable therefore, to separate remaining particulates and the high BP nucleates at an elevated temperature while the desirable lower boiling point hydrocarbon compounds are still vaporous. The venturi 40 may be operated from about 350 C to 450 C to remove these nucleates and cause forced nucleation of many of the high BP components. This may be followed by forcing the mist into the absorber 54 via a port 56 that is deliberately angled downwardly to the initial collection chamber 57 to prevent the high BP mist particles from continuing upward into the lower temperature condensing zones above. In testing, as much as 95% of the char fines and quinoline insoluble particulates were retained in with the high BP fraction in the lowest zone of the absorber 54 .
[0035] The ventruri 40 also serves to wet and mix the evolved gases. A source of fluid 42 may be heated or cooled as needed at heat exchangers 44 , 46 fed by sources of heating fluid 48 or cooling fluid 50 . The fluid source 42 is heated or cooled to a desired temperature (e.g. 350-500 C) in response to temperature sensor T, temperature control module TC, and temperature control valves TCV, and is then fed to the inlet of the venturi 40 to mix and wet the effluent gases 16 . Pressure sensors, P, monitor the pressure above and below the throat of the venturi 40 and a pressure differential control module, DPC, adjusts the venturi throat to maintain a predetermined pressure differential. Such venturi devices suitable for use with the invention are available from: Sly, Inc., Strongsville, Ohio; Envitech, Inc. San Diego, Calif.; Monroe Environmental, Monroe, Mich.; and AirPol, Ramsey, N.J. The outlet of the venturi feeds line 52 which feeds the inlet of a quench tower or absorber 54 (See FIG. 2B ).
[0036] The quench tower or absorber 54 condenses and separates volatile components from the evolved gases 16 . According to an embodiment of the invention, the absorber 54 is divided into multiple condensation zones, i.e. two or more, preferably at least three zones. Referring to FIG. 2 , three such condensation zones are shown, such as zones A, B and C, as identified by process sampling points IV, VI and VIII. These zones are maintained at increasingly lower temperatures as one progresses upward in the absorber tower. The three condensation zones result in heavy, mid and light CDL fractions being condensed and separated from the evolved gases. Additionally, a fine mist of additional light condensables may escape entrained in the gas stream, and may be processed as described below. While three such condensation zones are depicted, it will be understood that any number of multiple stage condensation zones is possible. The greater the number of condensation zones and the finer the temperature control in each one, the more uniform will be the condensed fractions resulting as the CDL components.
[0037] Other than the temperature at which each zone is set to condense, the structure of each is similar, so that only zone B is described in detail herein, it being understood that each such zone will have similar structures and function. Liquid condensed in zone B drains into a chimney tray 58 . The chimney tray 58 allows gas to pass through a multiplicity of chimney ducts or tubes while collecting the liquid in the volumetric space above the tray and surrounding the chimney ducts. The condensed liquid is drawn away from the chimney tray 58 by means of a pump 60 , optionally through a valve 62 and strainer 64 . A level meter L and a level control LC maintain the draw rate so as maintain a minimal threshold level at the bottom of zone B. The withdrawn liquid is carried to a heat exchanger 68 where it transfers its heat to a coolant fluid that is pumped through the heat exchanger 68 from a source 70 and to which it may return in a loop. A temperature sensor T monitors the temperature of the liquid exiting the heat exchanger 68 and temperature controller TC controls the temperature control valve TCV to control the flow of coolant to the heat exchanger 68 .
[0038] A portion of the cooled fluid exiting the heat exchanger 68 is diverted back to the top of zone B and to sprayers 72 which spray the liquid onto the hot gases to initiate further condensation, thus completing the loop. A flow meter F and flow control FC control the flow control valve FCV to maintain a constant flow rate to the sprayers 72 . The remainder of the cooled fluid exiting the heat exchanger 68 (process sampling point VII) is carried to an optional separator, such as centrifuge 74 , for further processing that will be described momentarily.
[0039] Zones A and C have similar liquid sprayer loops that are cooled by heat exchangers and aid in condensation. These heat exchangers are conventional in using a coolant fluid to exchange heat with the hot gases thereby cooling them to condense the volatile components with boiling points below the target temperature range, while not condensing volatile components with lower boiling points. Thus, the temperature set points for zones A, B, and C are all likely to be different, however, with the set point decreasing in succession from A to C. Typical temperature ranges for a three zone absorber are discussed below. The excess condensed liquid from Zone A (process sampling point V) is carried to an optional separator, such as centrifuge 76 , and the excess condensed liquid from Zone C (process sampling point IX) is carried to an optional separator, such as centrifuge 78 . Also, bottoms may be bled from the strainer below Zone A, to combine with sludge and/or use as a binder in a subsequent pelleting or briquetting operation.
[0040] Although shown as a loop configuration in FIG. 2B , heat from the heat-exchanged coolant may optionally be recovered in a heat recovery area to be used for other heating needs such as, for example, a sweep gas, a warmer or dryer, or any other process step requiring the input of heat.
[0041] Within each zone at the temperature (or range) of its set point, a certain fraction of the volatiles condense depending on their boiling points and vapor pressure within the mixture. Assuming a light CDL loop target temperature in Zone C of about 77 C+/−5, as shown in the schematic of FIG. 2 , a certain percentage of the condensable evolved gases remain as a mist of fine droplets in the gas stream. This mist evolves from the absorber at the top 80 (process sampling point X) and may be fed to a gas cleaning unit or particle separator, such as a wet electrostatic precipitator (ESP) 82 , which is used in the gas cleaning area to separate the mist droplets from the gas stream. The mist droplets contain additional light CDL and may be combined with previously fractionated light CDL as shown in FIG. 2 (process sampling point XI). Suitable ESPs are available from Lodge (KC) Cottrell, Inc., The Woodlands, Tex.; and/or Hamon Research-Cottrell, Inc., Somerville, N.J.
[0042] Suitable absorbers or quench towers are assembled from parts made by commercial suppliers such as Koch-Glitsch, LP, Wichita, Kans.; Sulzer Chemtech USA, Inc., Tulsa, Okla.; Raschig-Jaeger Products, Inc., Houston, Tex.; and others.
[0043] The gas stream leaving the precipitator 82 often contains traces of condensable hydrocarbon compounds and typically 20 to 30 weight % uncondensed moisture, the temperature typically at about 75 to 85C. For use as a fuel, it is desirable to remove some or most of the moisture and thereafter to reheat the gas to eliminate further condensation of either hydrocarbon compounds or water. Carryover of water is undesirable in the fuel as it lowers the calorific heating value of the fuel gas. Carryover of traces of condensable hydrocarbons which may condense in long gaseous fuel delivery conduits causing buildup and reduced flow path en-route to the fuel point of use is undesirable. Accordingly, the gas stream is then carried to a cooler 84 ( FIG. 2C ) where it is cooled to about 50 C in order to remove any water vapor that may remain. Water collects in a sump 86 (process sampling point XVI) and may be waste or used for other purposes.
[0044] The noncondensable gas that exits the cooler 84 is known as syngas or gaseous fuel and generally is composed of hydrogen, carbon oxides, water, and C 6 or shorter hydrocarbons. Table C (Below) lists many of these components. This process gas is sometimes burned off as flame, but may also be an important product gas itself. Optionally, this gas is reheated by a heat exchanger 88 to avoid condensation in long pipelines, and pumped by fan 90 to storage or to a location for further use, such as a fuel. The process gas may flow at typical rate of 6,000 to 10,000 kg/hour and may be reheated to about 60 C prior to being piped to a gas user.
[0045] In an important variation, a portion of the gas stream may be taken from a split point directly after the electrostatic precipitator 82 (process sampling point XIV) and pumped by fan 92 to the pyrolysis chamber(s) for use as a sweep gas without cooling. From 0% to 100% of the gas stream may be used for pyrolysis sweep gas, more typically from 40% to about 80%. If any portion of the gas stream is desired for pyrolysis, it is more energy efficient to bypass the cooler 84 and re-heater 88 .
[0046] Depending on the type of coal and pyrolysis conditions, a typical three condensation zone absorber may be designed and configured to condense about 20% (+/−5%) heavy CDL fraction, about 25% (+/−5%) mid CDL fraction and about 20% (+/−5%) light CDL fraction in the three condensation loops as shown in FIG. 2 . An additional 35% (+/−10%) by weight of light CDL condensables may exist in the mist droplets that escape to the electrostatic precipitator 82 which, when combined with the other light CDL fraction, yields about 55% of the total condensable portion.
[0047] As previously noted, the CDL condensed in Zone B is led to a centrifuge 74 ( FIG. 2C ). More generally, the condensed CDLs form each condensation zone may be further purified, filtered or separated to remove unwanted components. Separations may include any one or more of centrifuges, cyclone separators, ultra-high efficiency cyclones, electrostatic precipitators (ESP), drop boxes, filters of suitable pore size, etc. to remove fine particulates. Suitable centrifuges are commercially available from Flottweg, North America, Independence, Ky.; GEA Westfalia Separator Group, Northvale, N.J.; and Haus Centrifuge Technologies, (Welco Expediting, LTD) Calgary, Alberta, CA, among others. Suitable filters are commercially available from, for example, Towner Filtration, Twinsburg, Ohio.
[0048] In one embodiment, the heavy CDLs are led to centrifuge 76 and the supernatant CDL portion may further be passed through a filter 96 . These optional separation steps further purify the heavy CDLs, removing sludge and particulates. Similarly, medium CDLs are led to centrifuge 74 and the supernatant CDL portion may further be passed through a filter 94 . These optional separation steps further purify the medium CDLs, removing sludge and particulates. Finally, light CDLs are led to centrifuge 78 and the supernatant CDL portion may further be passed through a filter 98 . These optional separation steps further purify the light CDLs, removing sludge and particulates. The sludge and particulates from each of the three centrifugation and three filtration steps may be combined and used elsewhere, for example in briquetting processes.
[0049] Even though we refer to fractions as high, medium and low BP fractions, it is well understood that there is a distinction between boiling points (BP) and the actual temperature at which the condensable components will condense. Each condensable component “boils” at the temperature at which its pure vapor pressure equals atmospheric pressure. In contrast, the fractional condensation temperature (FCT) takes into account the fact that these compounds are in mixtures and each exerts only a partial vapor pressure—they are not pure. The fractional condensation curve table below (Table A) correlates the condensation zone target temperature with the approximate percent (by weight) of the CDL fraction that will condense under typical conditions, making certain assumptions about the partial pressure level of condensable components vs. the non-condensable components. Component-specific FCT estimates are discussed below in connection with FIG. 3 .
[0000]
TABLE A
Fractional Condensation Temperatures (FCT)
Condensation Curve,
Estimated Condensation
Temp
Temp
assuming 100%
Curve, assuming 25%
(F.)
(C.)
condensables
condensables
995
535
0%
0%
937
502.8
5%
885
473.9
10%
849
453.9
15%
822
438.9
20%
5%
794
423.3
25%
766
407.8
30%
738
392.2
35%
715
379.4
40%
687
363.9
45%
10%
685
362.8
658
347.8
50%
629
331.7
55%
601
316.1
60%
595
312.8
15%
572
300
65%
541
282.8
70%
512
266.7
75%
495
257.2
20%
483
250.6
80%
449
231.7
85%
420
215.6
30%
414
212.2
90%
369
187.2
95%
350
176.7
40%
300
148.9
50%
270
132.2
100%
260
126.7
60%
230
110
70%
200
93.3
80%
160
71.1
100%
[0050] In selecting a target temperature for each zone, it should be recalled that all volatile components having a fractional condensation temperature (FCT) above the target temperature for the particular zone are likely to condense in that zone. Thus, tradeoff decisions are to be made about how many fractions are desired and how fine or broad a temperature window is needed for capturing that entire component without undue impurities. These are traded off against the cost and efficiency of additional condensation loops, and the desire and ability to further refine the fractions as collected. It should be understood that the target temperature to maintain in the condensation loops will typically be at the lower end of the ranges described herein, in order to recover all condensable components in the desired fraction.
[0051] For example, in a three loop condensation zone process as described in FIG. 2 , the temperature may be set to collect three fractions in the condensation loops—heavy, middle and light fractions—having respectively approximately 20%, 25% and 20-25% by weight of the condensable components. Another 30-35% light CDL found in the entrained mist may be precipitated and combined with the 20-25% from the exchange loop. With these assumptions, the heavy fraction target might be set at a temperature from about 450 F (232 C) to about 550 F (288 C), preferably about from about 470 F (243 C) to about 530 F (278 C). The middle fraction target might be set at a temperature from about 250 F (121 C) to about 400 F (204C), preferably about from about 250 F (121 C) to about 350 F (177 C). The light fraction target migh t be set at a temperature from about 150 F (65 C) to about 250 F (121 C), preferably about from about 160 F (71 C) to about 220 F (105 C).
[0052] It will be understood that a desire to collect additional fractions will require additional target temperatures determined according to similar logic, but with narrower temperature windows. Similarly, a desire to collect fractions that are smaller or larger than the assumed 20% heavy, 25% mid, 20% light CDLs (plus 35% additional light CDL in the mist) will require adjustments to the target temperatures as well, based on theoretical BP curves modified to fit the altered assumptions, or on empirical experience.
[0053] More specifically, it is known that each CDL component of the hydrocarbon gases has a fractional condensation temperature (FCT) that is a function of the partial pressure or vapor pressure of that compound in a mixture. Since effluent gases from the pyrolysis of coal produces a complex mixture of many compounds, each exerts only a fraction of the approximately 1 atm experienced in the system. FIG. 3 illustrates the relationship between equilibrium vapor (or partial) pressure and temperature for twenty (20) of the most common condensable hydrocarbons present in effluent gases. Notably all are C 6 or larger and some are cyclic compounds. Curve M, for example, shows that m-Cresol at 1 atm should condense at about 200C, but at only 0.2 atm, would condense at about 140 C. Other compounds similarly have FCTs that are reduced from their BPs depending on their fractional concentration, as shown in FIG. 3 .
[0054] From the blending area, the coal char, coal fines, and particulates removed from the various CDL fraction may all be blended together to form fuel pellets or briquettes. In some embodiments, a portion of the heavy CDL fraction may optionally be used as a binder for the briquettes. Sludge 34 (with or without char fines) may also optionally be used as a binder for the briquettes.
EXAMPLE I
[0055] A process and apparatus is set up substantially as schematically described in FIG. 2 except no cyclone or venturi is used. Pyrolysis gas feed of 64,000 lbs/hr (29,030 kg/hr) is established with a breakdown as follows:
15,000 lbs/hr (6,804 kg/hr) condensable components (CDLs); 22,000 lbs/hr (9,979 kg/hr) of a sweep gas used to heat the pyrolysis chamber as described in US2011/0011722 to Rinker; 27,000 lbs/hr (12,247 kg/hr) non-condensable or syngas component.
[0059] This produces a condensable partial pressure of about 23.4% (15,000/64,000), i.e. approximately 25%. A three condensation zone absorber is arranged with heat exchange loops maintained at target temperatures of:
[0060] about 495 F (257 C) for the heavy CDL fraction
[0061] about 300 F (149 C) for the middle CDL fraction, and
[0062] about 170 F (77 C) for the light CDL fraction.
[0063] This configuration is designed to produce respective fractions of about 20% heavy, 25% middle and 55% light, with about 20% of the light being condensed in the exchange loop and an additional 35% recovered from an entrained mist in the air stream by an electrostatic precipitator in the gas cleaning area.
EXAMPLE II
[0064] A process and apparatus substantially as schematically described in FIG. 2 is set up. Seventeen process sampling points designated by Roman numerals from I to XVII are monitored and produce the data from Table B, below. A pyrolysis effluent gas feed of 41,813 kg/hr is delivered to a cyclone at about 473 C, which removes about 4655 kg/hr of particulates or about 11% by weight, leaving 37,158 kg/hr to flow into the absorber. Various fractions of CDLs (a combined total of 8,082 kg/hr) are removed at temperatures as shown in the Table B. Of this, about 24% is heavy CDL from zone A, about 30% is medium CDL from zone B, and about 25% from Zone C plus another 22% from the electrostatic precipitator totals about 47% light CDLs. This leaves about 27,409 kg/hr in non-condensable gases. The noncondensable gas stream is split, with approximately ⅔ (17,988 kg/hr) returning to the pyrolysis area as a sweep gas, and about ⅓ (9,424 kg/hr) being cooled to remove water and stored and/or supplied as a dried gaseous fuel. The characteristics of a gaseous fuel from a similar experiment with different flow rates are given in Table C below. Of course, the flow rates, volumes, capacities and the like are merely examples of the capabilities of the invention. Moreover, the gaseous fuel produced in this manner has a high heating value, for example in excess of 8000 BTU/lb. As seen from Table C, 124,000,000 BTU/hr divided by 15,044 lb/hr gives a fuel heating value of 8,241 BTU/lb (or 21.05 MJ/kg).
[0000]
TABLE B
FRACTIONATING COMPONENTS FROM A PYROLYSIS GAS STREAM
I
II
III
Pyrolysis
Pyrolysis
Dust out
IV
V
VI
VII
VIII
IX
X
Gas To
Gas To
from
Gas into
Heavy Oil
Gas into
Medium Oil
Gas into
Light Oil
Gas into
Cyclone
Venturi
Cyclone
Zone A
Fraction Out
Zone B
Fraction Out
Zone C
Fraction Out
ESP
T (° C.):
473
473
473
400
273
~170
150
100
72
77
Moisture:
24%
27%
27%
29%
43%
27%
30%
Flow:
kg/hr
kg/hr
kg/hr
kg/hr
kg/hr
kg/hr
kg/hr
kg/hr
kg/hr
kg/hr
H 2
172
172
172
172
172
172
CO 2
8931
8931
8931
8931
8931
8931
H 2 O
9990
9990
9990
9990
1250
8740
8740
CO
2954
2954
2954
2954
2954
2954
CH 4
2750
2750
2750
2750
2750
2750
C 2 H 6
925
925
925
925
925
925
C 2 H 4
281
281
281
281
281
281
C 3 H 8
498
498
498
498
498
498
C 3 H 6
415
415
415
415
415
415
C 4 H 10
201
201
201
201
201
201
C 4 H 8
313
313
313
313
313
313
C 4 H 6
5
5
5
5
5
5
C 5 H 12
148
148
148
148
148
148
C 5 H 10
170
170
170
170
170
170
C 6 +
848
848
848
848
848
848
S
58
58
58
58
58
58
CARBON
5072
417
4655
417
417
OIL
8082
8082
8082
1975
6207
1675
4532
2406
2126
Total
41,813
37,158
4655
37,158
2292
34,866
2925
31,941
2406
29,535
XI
XII
XIII
XIV
XV
XVI
XVII
ESP Oil
Total Light Oil
Total Wet Gas
Sweep Gas
Wet Gas to
Condensed
Net Dry
Fraction Out
Fraction Out
From ESP
to Pyrolysis
Coder
Water
Gas
T (° C.):
77
74
77
77
77
50
60
Moisture:
32%
31%
35%
100%
10%
Flow:
kg/hr
kg/hr
kg/hr
kg/hr
kg/hr
kg/hr
kg/hr
H 2
172
115
57
57
CO 2
8931
5968
2963
2963
H 2 O
8740
5488
3255
2600
855
CO
2954
1980
974
974
CH 4
2750
1840
910
910
C 2 H 6
925
620
305
305
C 2 H 4
281
190
91
91
C 3 H 8
498
335
163
163
C 3 H 6
415
280
135
135
C 4 H 10
201
135
66
66
C 4 H 8
313
210
103
103
C 4 H 6
5
3
2
2
C 5 H 12
148
100
48
48
C 5 H 10
170
115
55
55
C 6 +
848
570
278
278
S
58
39
19
19
CARBON
OIL
2126
4532
Total
2126
4532
27409
17,968
9424
2600
6824
[0000]
TABLE C
GASEOUS FUEL CHARACTERISTICS
Composition
Mass Flow
Higher Heating Value
Component:
(Mass %)
(lb/hr)
(kg/hr)
(Btu/lb)
(MM BTU/hr)
MW
Hydrogen
H 2
0.84%
126
57
61,100
7.68
2.25
Carbon Dioxide
CO 2
43.42%
6532
2963
Water Vapor
H 2 O
9.60%
1444
655
Carbon Monoxide
CO
14.27%
2147
974
4,347
9.33
2.74
Methane
CH 4
13.34%
2006
910
23,879
47.91
14.04
Ethane
C 2 H 6
4.47%
672
305
22,320
15.01
4.40
Ethylene
C 2 H 4
1.33%
201
91
21,644
4.34
1.27
Propane
C 3 H 8
2.39%
359
163
21,661
7.78
2.28
Propylene
C 3 H 6
1.98%
298
135
21,041
6.26
1.84
Butane
C 4 H 10
0.97%
146
66
21,308
3.10
0.91
Butene
C 4 H 8
1.51%
227
103
20,840
4.73
1.39
Butadiene
C 4 H 6
0.03%
4
2
20,635
0.09
0.03
Iso Pentane
C 5 H 12
0.70%
106
48
21,052
2.23
0.65
Pentene
C 5 H 10
0.81%
121
55
20,712
2.51
0.74
C 6 +
4.07%
613
278
20,940
12.83
3.76
Sulfur
S
0.28%
42
19
3,983
0.17
0.05
Total
100.0%
15,044
6824
124
36
[0065] While the invention has been described with reference to various and preferred embodiments, it should be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the essential scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof.
[0066] Therefore, it is intended that the invention not be limited to the particular embodiment disclosed herein contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims.
|
A method for treating coal includes drying coal in an initial drying step. The dried coal is pyrolyzed in a pyrolysis step to form coal char and evolved gases. The coal char is eventually cooled and blended. The evolved gases are condensed in at least two, preferably three or more, distinct zones at different temperatures to condense coal-derived liquids (CDLs) from the evolved coal gas. Noncondensable gases may be returned to the pyrolysis chamber as a heat-laden sweep gas, or further processed as a fuel stream. The CDLs may optionally be centrifuged and/or filtered or otherwise separated from remaining particulate coal sludge. The sludge may be combined with coal char, optionally for briquetting; while the CDLs are stored. Precise control of the condensing zone temperatures allows control of the amount and consistency of the condensate fractions collected.
| 2
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an ink jet recording head that obtains recorded images by discharging ink to the recording surface of a recording medium.
2. Related Background Art
There has been practically provided an ink jet recording apparatus that forms images by the adhesion of the ink on the recording surface of a recording medium, which is discharged selectively thereto from plural ink discharge ports in accordance with recording data. For the ink jet recording apparatus of the kind, the ink jet recording head, which is selectively mounted on a carriage, is provided and arranged to face the recording surface of the recording medium and scan in the direction orthogonal to the conveying direction of the recording medium.
As shown in FIG. 8, an ink jet recording head 16 of the so-called side shooter type comprises, for example, the main body portion 18 formed by an ink supply portion 18 B having an ink tank IT installed thereon, and an input terminal portion 18 A electrically connected with a carriage portion (not shown) to receive a driving control signal group form the carriage portion; a supporting member 20 connected with the joining face 18 b of a recess 18 BG of the ink supply portion 18 B of the main body portion 18 ; a recording element base plate 24 bonded to the upper face that serves as a second bonding face of the supporting member 20 ; and a printed circuit board 22 electrically connected with the recording element base plate 24 to supply the driving control signal group from the input terminal portion 18 A.
The input terminal portion 18 A and ink supply portion 18 B of the main body portion 18 are formed integrally by resin, for example. On the upper face of the ink supply portion 18 B of the main body portion 18 opposite to the portion where the ink tank IT is installed, an almost rectangular recess 18 BG is arranged as shown in FIG. 8 and FIGS. 9A and 9B. The bottom face of the recess 18 BG is made to be the joining face 18 b where the supporting member 20 is bonded. A part of the joining face 18 b is formed by the surface of a block piece 26 of aluminum alloy, for example. The block piece 26 is arranged in a metallic die and surrounded by resin when the main body portion 18 is formed. Almost on the central portion of the joining face 18 b , there opens the thin and long end portion of the ink supply path 18 a that induces ink from the ink tank IT.
As shown in FIG. 10 and FIG. 11, the recording element base plate 24 comprises the base plate 10 having an ink supply port 10 c communicated with the opening end portion of the ink supply path in the ink supply portion; partition wall members 12 that form plural ink branch supply paths 12 a arranged corresponding to heaters 10 a serving as the ink heating portion on the base plate 10 ; and an orifice plate 14 having plural ink discharge ports 14 a arranged in two line formation corresponding to each of the heaters 10 a on the base plate 10 .
For the recording element base plate 24 , a silicon thin film is formed in a thickness of 0.5 mm to 1.0 mm, for example. Also, as shown in FIG. 9A, the surface of the recess 18 BG of the ink supply portion 18 B of the base plate, which is bonded to the joining face 18 b by the application of a bonding agent, is provided with the ink supply opening portion 24 c facing the orifice plate, which is extended in the arrangement direction of the ink discharge ports 24 a . Further, on both sides of the base plate having the ink supply opening portion 24 c between them, heaters (not shown) are arranged with designated gaps between them, respectively. The ink supply opening portion 24 c is communicated with one end portion of the ink branch supply paths provided for the partition wall members. Each of the ink branch supply paths induces to each heater the ink that is supplied through the ink supply opening portion 24 c.
As shown in FIG. 8 and in FIGS. 9A and 9B, the printed circuit board 22 is electrically connected with each of the electrodes of the base plate for the recording element base plate 24 . The printed circuit board 22 is provided with the containing portion 24 B of the recording element base plate where the recording element base plate 24 is arranged, and a terminal portion 24 A, which is arranged for the input terminal portion 18 A of the main body portion 18 . For the bonding of the printed circuit board 22 and the recording element base plate 24 , the TAB (tape automated bonding) method is adopted, for example.
The supporting member 20 , which is arranged between the recording element base plate 24 and the joining face 18 b of the recess 18 BG of the ink supply portion 18 B, is formed to be flat and rectangular as shown in FIG. 8 and FIGS. 9A and 9B. Here, the same silicon material used for the recording element base plate 24 forms the supporting member 20 , for example.
As shown in FIG. 9A, the supporting member 20 is provided with a second joining face 20 Sa bonded to the surface arranged for the ink supply opening portion 24 c of the recording element base plate 24 , and a first joining face 20 Sb bonded to the joining face 18 b of the recess 18 BG of the ink supply portion 18 B. Also, the supporting member 20 is provided with a communication path 20 a , which is extended to be thin and long in the longitudinal direction, in a position facing the ink supply path 18 a arranged for the ink supply opening portion 24 c of the recording element base plate 24 and the joining face 18 b of the recess 18 BG of the ink supply portion 18 B. Further, the length of the shorter side and longer side of the supporting member 20 are the same as that of the shorter side and longer side of the recording element base plate 24 , respectively, and the thickness of the supporting member 20 is substantially the same as that of the recording element base plate 24 .
When arranging the recording element base plate 24 having the printed circuit board 22 connected therewith for the ink supply portion 18 B, the first joint face 20 Sb of the supporting member 20 is bonded, at first, to the designated position on the joining face 18 b by use of bonding agent. Then, in continuation, as shown in FIG. 9B, the second joining face 20 Sa of the supporting member 20 is bonded to the surface having the ink supply opening portion 24 c arranged for the recording element base plate 24 by use of a bonding agent. Here, it is desirable to use a bonding agent having low viscosity and thin bonding layer to be formed on the contact face, and comparatively high hardness once cured.
With the structure thus arranged, when each of the heaters is heated on the base plate of the recording element base plate 24 with the supply of a heater driving control signal through the printed circuit board 22 , ink is induced by way of the ink supply path 18 a through the ink branch supply paths of the partition member. Then, ink is heated by each of the heaters to generate a bubble by means of a film boiling phenomenon, and along with the expansion of the bubble, ink is discharged from each of the ink discharge ports 24 a toward the recording surface. However, there are the following problems encountered by the conventional example described above.
In other words, it is found that when the number of nozzles should increase and the length of the recording element base plate should be made larger still, the problems identified below occur sometimes irrespective of the case where the base plate is formed by the same silicon material used for the supporting member or formed by alumina or the like, the linear expansion coefficient of which is similar to that of silicon. Now, hereunder, the problems will be discussed more specifically in accordance with the properties of bonding agents used for bonding the supporting member and the recording element base plate.
(1) In a Case of a Thermal Curing Bonding Agent
When the recording element base plate and the supporting member are bonded by use of thermal curing bonding agent, the curing temperature is higher than the room temperature. In other words, the aluminum blocks of the main body portion, as well as the supporting base plate and the recording element base plate, are all bonded in a state of being expanded at a temperature higher than room temperature. Then, after bonding, as the temperature of recording head is lowered, each of the members is contracted. Generally, the linear expansion coefficient of the aluminum blocks is greater than that of the recording element base plate and the supporting base plate. Thus, the ratio of contraction thereof is greater when the temperature of the recording head is lowered. As a result, when the recording head returns to room temperature after bonding, the dimensional changes of the aluminum blocks are greater than those of the recording element base plate and the supporting base plate, hence generating stresses among the recording element base plate, supporting base plate, and the aluminum blocks. When the number of nozzles is small, and the length of the recording element base plate is small, the dimensional changes are also small when the temperature changes. The exertion of stresses is small accordingly. Therefore, if silicon or alumina is used for the supporting base plate, it is possible to minimize the amount of deformation of the recording element base plate because the use of such material can resist the occurrence of stresses. However, with the increase in nozzle numbers, the recording element base plate needs to become longer. Then, the difference between the dimensional changes of the recording element base plate, the supporting base plate, and the aluminum blocks becomes greater after curing, and the occurrence of stresses becomes greater accordingly. Consequently, even when silicon or alumina is used for the supporting base plate, it becomes difficult to resist the stresses thus exerted, and in some cases, the recording element base plate is deformed greatly. If such deformation takes place, the impact position of ink droplets from the recording head of an ink jet recording apparatus is caused to shift, resulting in the degradation of printed images or, further, the recording element base plate may be broken in some cases.
(2) In a Case of a Cold Curing Bonding Agent
When the cold curing bonding agent, which is cured at a temperature close to room temperature, is used for bonding the recording element base plate and the supporting member, there is no such problem as described above. However, if the temperature of the recording head rises during printing operation, the same problems take place. In other words, when the head temperature rises during the printing operation, the aluminum blocks, recording element base plate, and the supporting base plate are expanded, and the dimensions of each of them become larger. Particularly, the linear expansion coefficient of the aluminum blocks is greater than that of the recording element base plate and supporting base plate, and the dimensional changes are great. Thus, when the temperature rises, a difference in dimensional changes occurs between the aluminum blocks, and the recording element base plate and supporting base plate. As a result, stresses occur among the recording element base plate, supporting base plate, and aluminum blocks. When the number of nozzles is small, and the length of the recording element base plate is small, the dimensional changes are also small when the temperature changes. The exertion of stresses is small accordingly. Therefore, if silicon or alumina is used for the supporting base plate, it is possible to minimize the amount of deformation of the recording element base plate because the use of such material can resist the occurrence of stresses. However, with the increase in nozzle numbers, the recording element base plate needs to become longer. Then, the difference between the dimensional changes of the recording element base plate, the supporting base plate, and the aluminum blocks becomes greater after curing, and the occurrence of stresses becomes greater accordingly. Consequently, even when silicon or alumina is used for the supporting base plate, it becomes difficult to resist the stresses thus exerted, and in some cases, the recording element base plate is deformed greatly. If such deformation takes place, the impact position of ink droplets from the recording head of an ink jet recording apparatus is caused to shift, resulting in the degradation of printed images or, further, the recording element base plate may be broken in some cases. Now, therefore, the present invention is designed to solve the problems discussed above, and it aims at the provision of an ink jet recording head capable of printing high-quality images at all times without the deformation of the recording element base plate due to the difference between the temperature at which the recording element base plate is bonded and room temperature, or due to temperature changes at time of driving, especially when the recording element base plate is made longer due to an increase in the number of nozzles.
SUMMARY OF THE INVENTION
In order to solve the aforesaid problems, the present invention provides an ink jet recording head structured as described in paragraphs (1) to (10) given below.
(1) An ink jet recording head comprises:
a recording element base plate having an ink heating portion for heating ink, and ink discharge ports for discharging ink heated by the ink heating portion;
a main body portion having ink supply path for inducing ink from an ink retaining portion; and
a connecting member having a first bonding surface bonded to the main body portion, and a second bonding surface bonded to the recording element base plate. For this head, the connecting member is formed by material having a weaker stretching strength than that of the recording element base plate.
(2) The ink jet recording head referred to in paragraph (1) for which the relationship between the connecting member and the recording element base plate is arranged to satisfy the following formula (i):
Es·ts 3 ·ws>Ea·ta 3 ·wa (i)
where
Es: Young's modulus (dyn/cm 2 ) of the recording element base plate
ts: thickness (cm) of the recording element base plate
ws: width (cm) of the recording element base plate
Ea: Young's modulus (dyn/cm 2 ) of the connecting member
ta: thickness (cm) of the connecting member
wa: width of the connecting member (cm)
(3) The ink jet recording head referred to in paragraph (1) or paragraph (2), for which the connecting member is formed from either a resin or a compound material of resin and metal.
(4) The ink jet recording head referred to in paragraph (1) or paragraph (2), for which the connecting member is formed from polyimide.
(5) The ink jet recording head referred to in any one of paragraphs (1) to (4), for which the connecting member is provided with electrode wiring for use in driving heat generating elements of the recording element base plate.
(6) The ink jet recording head referred to in any one of paragraphs (1) to (5), for which the connecting member is structured to laminate an electrode wiring with resin.
(7) The ink jet recording head referred to in any one of paragraphs (1) to (6), for which the recording element base plate and the main body portion are each provided with a portion for bonding the recording element base plate and the main body portion directly to each other.
(8) The ink jet recording head referred to in paragraph (7), for which the portions of direct bonding of the recording element base plate and the main body portion are arranged at plural locations.
(9) The ink jet recording head referred to in any one of paragraphs (1) to (10), for which the bonding center of the first bonding surface and the bonding center of the second bonding surface are arranged to shift in the horizontal direction.
(10) The ink jet recording head referred to in the paragraph (9), for which the bonding portions are arranged from a central area of the main body portion to a periphery thereof the following order: the area of in the direct bonding between the recording element base plate and the main body portion, the second bonding portion, and the first bonding portion.
With the adoption of the structure described above when embodying the present invention, the recording element base plate, which is arranged to obtain recorded images by discharging ink to a recording medium, is bonded and fixed to the main body, hence making it possible to provide an ink jet recording head capable of printing high-quality images at all times without deforming the recording element base plate due to the difference in the bonding temperature of the recording element base plate and the room temperature or due to the temperature changes at the time of driving, even if the number of nozzles increases and the recording element base plate is made longer.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view that shows the structure of an ink jet recording head in accordance with a first embodiment of the present invention.
FIGS. 2A and 2B are views that illustrate the structure of the ink jet recording head in accordance with the first embodiment of the present invention.
FIG. 3 is a view that shows the structure of a second embodiment in accordance with the present invention.
FIG. 4 is a view that shows the structure of the second embodiment in accordance with the present invention.
FIG. 5 is a view that shows the structure of a third embodiment in accordance with the present invention.
FIG. 6 is a view that shows the structure of the third embodiment in accordance with the present invention.
FIG. 7 is a view that shows the structure of the third embodiment in accordance with the present invention.
FIG. 8 is a view that shows the structure of the conventional ink jet recording head.
FIGS. 9A and 9B are views that illustrate the structure of the conventional example.
FIG. 10 is a view that shows the inner details of the conventional recording element base plate.
FIG. 11 is a view that shows the conventional recording element base plate and printed circuit board.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, the embodiments will be described in accordance with the present invention.
First Embodiment
FIG. 1 and FIGS. 2A and 2B are views that illustrate the structure of an ink jet recording head 50 in accordance with a first embodiment of the present invention. FIG. 1 is a perspective view showing the ink jet head 50 . FIGS. 2A and 2B are cross-sectional views schematically illustrating the ink jet head 50 represented in FIG. 1 . In these figures, however, the flow paths provided for the recording element base plate, and the structure of the discharge port portion are omitted. Now, in conjunction with FIG. 1 and FIGS. 2A and 2B, the present embodiment will be described. Here, a reference numeral 1 designates the main body portion; 2 , the recording element base plate that discharges ink from the discharge ports; and 3 , the connecting member, which is bonded between the main body portion and the recording element base plate. These three constituents structure the ink jet recording head 50 of the present embodiment significantly.
In this respect, the main body portion 1 is provided with the ink supply portion 1 a to which ink is supplied from an ink tank, and the input terminal portion 1 b to which driving signal group is inputted from a carriage portion (not shown).
To the recording element base plate 2 , the driving control signal group is supplied through the input terminal portion 1 b by means of a printed circuit board (not shown). The inner structure of the recording element base plate 2 is the same as that of the recording element base plate to be shown in FIG. 10 . Therefore, the description thereof will be omitted. The recording element base plate 2 is formed by silicon material in a thickness of 0.5 to 1.0 mm. On the bonding surface A′ side, the connecting member 3 is bonded thereto, and there is arranged the ink supply opening portion 54 (see FIG. 2 A), which extends in the arrangement direction of the ink discharge ports 51 . Here, a reference numeral 53 designates the discharge port array.
For the ink supply portion 1 a of the main body portion 1 , the liquid chamber 1 d , which is recessed substantially in a rectangular form, is provided. Almost on the center of the liquid chamber 1 d , the thin and long opening portion is arranged for inducing ink from an ink-retaining portion (not shown), and a filter 1 e is arranged thereon to remove dust particles in the ink. Further, for the liquid chamber 1 d , a recording element supporting portion 1 c is provided to connect the main body portion 1 and the recording element base plate 2 directly. With the direct connection between the recording element supporting portion 1 c and the connecting member 3 , it becomes possible to maintain the position of the recording element base plate 2 in high precision.
The bonding surface B of the connecting member 3 is bonded to the bonding surface B′ of the main body portion 1 . Also, the bonding surface A of the connecting member 3 is bonded to the bonding surface A′ of the recording element base plate 2 . Each of the bonding areas 55 which is actually bonded, as shown in FIG. 2A, is part of bonding surfaces A, A′ and bonding surfaces B, B′, respectively, and each of them shifts horizontally. On the center of the connecting member 3 , there is open the ink supply port 52 as a communication port, through which ink is supplied from the liquid chamber 1 d to the ink supply opening portion 54 of the recording head.
The connecting member 3 is formed by resin, such as polyimide, in a thickness of as thin as approximately 0.5 mm, for example, having a stretching strength that is weaker than that of the recording element base plate 2 . Polyimide is soft and has resistance to heat, but is not easily affected by the ink component. Therefore, it is particularly suitable for the connecting member 3 . In this respect, however, the material of this member is not limited to resin. It may be possible to use thin metal, such as SUS or a compound material of metal and resin, such as a multiple layered laminate material of aluminum (Al) and resin. If metal is used, the gas barrier capability is enhanced to make it possible to suppress the ink evaporation to an extremely low level. However, the range of selection of the kinds of metal, which is not easily affected by the ink component, and not dissolved to cause burning either, is limited. In addition, metal has a comparatively strong starching capability even in a small thickness, thus presenting the disadvantage that the recording element base plate tends to be deformed easily. In contrast, a compound material of resin and metal has a multiple layered structure having a thin metal plate or a metal deposition film sandwiched with resin. Thus, the metal is not directly in contact with the ink component. It is not affected by ink and it does not cause burning either. Furthermore, the sandwiched metallic film suppresses ink evaporation. Therefore, this structure is particularly suitable for the purpose.
Also, the connecting member is good enough if it has a stretching strength weaker than that of the recording element base plate, and preferably, it satisfies the following relationship:
Es·ts 3 ·ws>Ea·ta 3 ·wa (i)
where
Es: Young's modulus (dyn/cm 2 ) of the recording element base plate
ts: thickness (cm) of the recording element base plate
ws: width (cm) of the recording element base plate
Ea: Young's modulus (dyn/cm 2 ) of the connecting member
ta: thickness (cm) of the connecting member
wa: width of the connecting member (cm)
With the structure thus arranged, the recording element base plate, the connecting member, the supporting member, and the ink supply member are bonded by use of a thermal curing bonding agent. Then, since the curing temperature is higher than room temperature, each of the members is bonded in a state of being expanded. After bonding, as the head temperature is lowered, each of the members is contracted. Usually, the supporting member and the ink supply member are formed from resin, and the linear expansion coefficient thereof is larger than that of the recording element base plate. Also, if resin is used for the connecting member, too, the linear expansion coefficient thereof becomes larger than that of the recording element base plate. As a result, the ratio of contraction is different in the recording element base plate and other members when the head temperature is lowered after bonding, and this difference results in dimensional changes. However, as described above, with the connecting member, the stretching strength of which is made weaker than that of the recording element base plate, the stresses exerted by the aforesaid thermal changes are absorbed by the deformation of the connecting member to make it possible to reduce the adverse effect on the recording element base plate. In this manner, it is possible to minimize the thermal influence on the recording head when using a thermal curing bonding agent.
Further, as has been described in the present embodiment, with the structure in which the bonding portion A A′ of the recording element base plate and the connecting member and the bonding surface B B′ of the connecting member and the main body portion shift in the horizontal direction (the axes thereof shift), while the stretching strength of the connecting member is made weaker than that of the recording element base plate, the stresses exerted by the difference in the dimensional changes between the recording element base plate and other members are absorbed by the deformation of the connecting member disposed between the bonding portion A A′ and the bonding portion B B′. Then, there is almost no influence exerted on the recording element base plate due to the aforesaid heat and stresses.
The absorption of stresses by the deformation of the connecting member between the bonding portions that shift as described above makes the amount of deformation significantly larger than that of the structure in which a recording element base plate and a main body portion are bonded directly by use of a soft bonding agent or resin, and the structure of the present ink jet recording head is excellent in the aspect of stress absorption effect.
As a result, by the adoption of the structure hereof, it is possible to execute the head assembling with almost no deformation of the recording element base plate even if the number of nozzles increases to make the length of the recording element base plate larger (particularly effective for the recording element base plate having a length of one inch or more, for example).
Also, with the direct bonding of the recording element supporting portions 1 c at the edges of the recording element base plate as shown in FIG. 1 and FIGS. 2A and 2B, the present embodiment provides the structure whereby the positional precision on the central area near the discharge ports is retained, while absorbing stresses on the circumference thereof. As a result, it is made possible to perform high-quality printing.
Also, the structure hereof is able to produce the same effects against the generation of stresses due to the difference in the expansion coefficient of each member, which is brought about by the temperature rise of the head during printing operation in the case where the recording element base plate, the connecting member, the supporting member, and the ink supply member are bonded by use of a cold (room temperature) curing bonding agent.
In other words, each of the members expands when the head temperature rises during printing operation such that the dimensions thereof increase. Usually, the supporting member and the ink supply member are formed of resin. Therefore, their linear expansion coefficients thereof are larger than that of the recording element base plate. Also, if the connecting member is formed of resin, the linear expansion coefficient thereof becomes larger than that of the recording element base plate. As a result, when the temperature rises during printing operation, a difference between dimensional changes ensues due to the difference between the expansion coefficient of the recording element base plate and those of other members.
However, as described above, with the connecting member the stretching strength of which is made weaker than that of the recording element base plate, it is possible to absorb the stresses exerted by the aforesaid thermal changes by means of deformation of the connecting member, so as to reduce any possible influence that may be given to the recording element base plate.
Further, in the embodiment described above, the bonding portion A A′ between the recording element base plate and the connecting member and the bonding surface B B′ between the connecting member and the main body portion are structured to shift in the horizontal direction (shift axes), and the stretching strength of the connecting member is made weaker than that of the recording element base plate. In this way, the stresses that should be exerted due to the difference in the dimensional change of the recording element base plate and those of other members are absorbed by the deformation of the connecting member disposed between the bonding portion A A′ and the bonding portion B B′. As a result, there occurs almost no influence of heat and stresses given to the recording element base plate.
Therefore, with the provision of the structure hereof, it is possible to execute the head assembling with almost no deformation of the recording element base plate even when the number of nozzles increases so that the length of the recording element base plate is made large (particularly effective for the recording element base plate of one inch or more, for example).
Second Embodiment
FIG. 3 and FIG. 4 are views that illustrate the structure of a second embodiment of the present invention.
For the present embodiment, the structure is arranged so that the connecting member 3 also serves as a printed circuit board that supplies a driving control signal group to the recording element base plate.
The structure is such that the electrodes of the connecting member 3 are laminated by resin, and that the carriage electrode-contacting portion 57 , which electrically connects the carriage with the electrode pads 56 electrically connected with the recording element base plate, is exposed on the resin layer. As shown in FIG. 4, the electrodes 58 of the connecting member 3 are wired to the electrode pads of the connecting member from the recording element base plate by means of wire bonders or the like installed on the main body portion.
The carriage electrode-contacting portion is installed on the sidewall of the main body portion by being folded in the direction indicated by the arrow in FIG. 4 .
In accordance with the present embodiment, it becomes unnecessary to prepare the printed circuit board that supplies the driving control signal group to the recording element base plate as a separate component, thus making cost reduction possible, while providing the same advantages as the first embodiment.
Third Embodiment
FIG. 5, FIG. 6, and FIG. 7 are views that illustrate a third embodiment of the present invention.
For the present embodiment, the structure is arranged so that the connecting member 3 has an area larger than the cross-sectional area of the main body portion 1 , and so that the connecting member 3 also serves as a heat-radiating portion. As shown in FIG. 6, the connecting member that projects outward from the main body is bent in the directions indicated by arrows, and installed on the side faces as shown in FIG. 7 .
The connecting member is formed by metallic material, resin-laminated metal, or metal laminated with resin only on the area which contacts ink and the heat-radiating portion of the connecting member is metal exposed for this purpose.
In accordance with the present embodiment, the temperature of the recording element base plate does not easily rise, because heat generated by the recording element base plate during printing can be effectively radiated externally through the connecting member. Furthermore, the amount of deformation of the recording element base plate is made smaller.
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An ink jet recording head includes a recording element base plate having an ink heating portion for heating ink, and ink discharge ports for discharging ink heated by the ink heating portion; a main body portion having an ink supply path for inducing ink from an ink retaining portion; and a connecting member having a first bonding surface bonded to the main body portion, and a second bonding surface bonded to the recording element base plate. For this head, the connecting member is formed by material having a weaker stretching strength than that of the recording element base plate. With the structure thus arranged, it is possible to provide an ink jet recording head capable of printing high-quality images at all times without deforming the recording element base plate due to the difference in the bonding temperature of the recording element base plate and room temperature, or due to temperature changes at the time of driving, even if the number of nozzles increases and the recording element base plate is made longer.
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FIELD OF THE INVENTION
[0001] The invention relates generally to bulldozers. More particularly, it relates to systems for keeping the blade of a bulldozer at a selected position as the bulldozer is operated.
BACKGROUND OF THE INVENTION
[0002] “Bulldozers” or “dozers”, as those terms are used herein, refer to crawler-tractors that are equipped with a blade for scraping the ground or pushing material along the ground. The blade is pivotally connected to the crawler-tractor chassis such that they can pivot up and down. Blade controls are provided to the operator in the cab of the vehicle. These controls permit the operator raise and lower the blade with respect to the chassis of the crawler-tractor. One of the most common uses for blades on bulldozers is to level or otherwise contour ground for construction of houses, buildings, parking lots, and roads. Often the terrain that the bulldozer starts working is quite uneven and rough. As it passes over this rough terrain, the bulldozer chassis often begins to pitch.
[0003] When the chassis pitches up and down, the blade pitches as well. As the blade pitches up the blade digs the earth shallower. As the blade pitches down, it digs into the earth deeper, duplicating in the earth the fluctuations of the dozer chassis as it pitches over the rough terrain. Instead of evenly leveling the terrain, a bulldozer tends to reproduce the very rough terrain over which it drives.
[0004] A skilled operator can reduce the pitching of the blade by anticipating the pitching of the chassis and moving the blade in the opposite direction. By manually pitching the blade in a direction opposite to the direction the chassis pitches and at exactly the same time, the operator can grade the terrain more level than if the blade merely pitches with the chassis. This ability to anticipate the motion of the chassis and pitch the blade in the opposite direction takes a good deal of skill, and that skill can only be acquired through experience.
[0005] Even a talented driver, however, cannot travel at full speed over rough terrain, but must reduce his speed to accommodate the pitching of the dozer blade as the dozer chassis pitches up and down as it travels over the ground.
[0006] The process of leveling the ground using a bulldozer blade is called “grading”. Systems for automatically grading the ground have been devised that use sensors mounted on a bulldozer blade and laser light sources located at the corners of a field to be graded. These light sources transmit light to the sensors attached to the bulldozer blade.
[0007] As a bulldozer equipped with these systems pitches backward or forward, the blade begins to pitch up or down, causing the light falling on the sensor to fall or rise, respectively. A controller coupled to the sensor controls blade pitching by raising and lowering the blade to keep it in the same position with respect to the ground.
[0008] This system, however, requires the careful placement and adjustment of light sources and an unobstructed view of the bulldozer blade.
[0009] What the inventors have discovered is that for many applications this laser-guided whole-field system is overkill. Many operators, especially novice operators, would be significantly benefited by a system that merely monitors bulldozer pitching as it goes over rough terrain and keeps the blade in a relatively constant position and at a relatively constant height as the chassis of the bulldozer pitches forward and backward.
[0010] What is needed, therefore, is a system for reducing dozer blade pitching as the dozer chassis pitches. What is also needed is a dozer that has a system for reducing dozer blade pitching. What is also needed is a system for keeping the dozer blade at a relatively constant height and at a relatively constant position as the chassis of the tractor-crawler pitches. What is also needed is a system that at least partially relieves the operator of the burden of manually raising and lowering the blade as the vehicle pitches while traveling over the ground. What is also needed is a system that permits the operator to grade faster by automatically controlling blade pitching. What is also needed is a system that automatically controls blade pitching faster than an operator can manually control blade pitching. It is an object of this invention to provide such system and bulldozer.
SUMMARY OF THE INVENTION
[0011] In accordance with a first aspect of the invention, a bulldozer is provided, comprising a crawler-tractor; a ground-engaging blade coupled to the crawler to raise and lower with respect to the crawler-tractor; at least one hydraulic lift cylinder configured to position the blade; a blade position sensor to provide a signal indicative of a position of the blade; and an electronic controller coupled to the blade and to the at least one lift cylinder to automatically raise the blade with respect to the crawler-tractor when the crawler-tractor pitches forward, and lower the blade when the crawler-tractor pitches backward, in response to position signals received from the blade position sensor.
[0012] The bulldozer may include two horizontally disposed arms pivotally coupled to left and right sides of the crawler-tractor that support the blade, an operator input device coupled to the controller, the input device including a member manually operable to transmit a signal indicative of a target blade position to the controller; wherein the controller includes a feedback control loop configured to drive the blade to a target position. The blade position sensor may be coupled to the controller to transmit the blade position signal to the controller. The controller may be configured to raise and lower the blade in response to the signal indicative of blade position. The signal indicative of blade position may indicate a rate of change of the blade angle that is perpendicular to a generally horizontal axis and laterally extending axis. The operator input device may be configured to generate the signal indicative of the target blade position in a first mode of operation and may be configured to generate a signal indicative of a desired rate of blade lifting in a second mode of operation. The blade position sensor may be fixed to the blade. The controller may include a CPU, RAM, and ROM.
[0013] In accordance with a second aspect of the invention, a pitch control system for controlling the pitch of the bulldozer blade is provided, including a blade position sensor configured to be fixed to the blade of the bulldozer to provide a signal indicating an actual position of the blade, a manually operable operator input device configured to be coupled to the controller to provide the controller with a signal indicative of a target position; and an electronic controller configured to be coupled to the blade position sensor and to the input device to receive the target position signal and the actual position signal, to determine the difference between the target position and the actual position and to calculate a valve signal for a hydraulic valve coupled to a blade lift cylinder that will drive the blade to the target position when the bulldozer pitches.
[0014] The signal indicating the actual position of the blade may also indicate the angular turning rate of the blade. The controller may include a CPU, a RAM, and a ROM, and the ROM may contain digital instructions that (a) determine the difference between the actual and the target positions and (b) may calculate the valve signal that will drive the blade to the target position. The angular turning rate may be the rate of change of the blade angle that is perpendicular to a generally horizontal axis that extends perpendicular to the length of the crawler-tractor. The blade position sensor may be an angular turning rate sensor. The input device may include a manually operable member that generates a signal that lowers the target position when moved in a first direction, and that raises the target position when moved in a second direction opposite the first direction.
[0015] In accordance with a third aspect of the invention, a computer-implemented method of controlling the pitching of a bulldozer blade during movement over the ground is provided, the method including the steps of (1) reading a blade actual position that indicates an actual position of the bulldozer blade; (2) comparing the blade actual position signal with a blade target position signal; (3) determining a hydraulic valve signal that is calculated to drive the blade from the actual position to the target position; and (4) driving the blade to the target position. The step of comparing may include the step of calculating an error signal indicating the difference between the blade's actual position and the blade's target position. The step of determining may include the step of calculating a control signal from the error signal, the control signal having a derivative component, a proportional component, and an integral component. The step of reading a blade actual position may include the step of reading the blade actual position from an angular turning rate sensor and integrating the turning rate to determine the blade actual position. The turning rate may be the rate of turning about a generally horizontal and laterally extending axis.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a side view of a bulldozer in accordance with the present invention.
[0017] FIG. 2 is a hydraulic and schematic diagram of a blade pitch control system in accordance with the present invention as shown on the bulldozer of FIG. 1 .
[0018] FIG. 3 is a flowchart of the functions performed by the controller of FIG. 2 when it executes its stored program and controls blade pitching.
[0019] FIG. 4 is a control diagram illustrating the control operations performed by the electronic controller of FIG. 3 that regulate the pitch of the blade.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] “Dozer” or “bulldozer” as used herein refers to a crawler-tractor coupled to a blade. “Crawler-tractor” refers to any of the class of work vehicles having a chassis, with an engine and ground-engaging endless-loop tracks that are disposed on either side of the chassis, that are driven by the engine, and that move the chassis over the ground.
[0021] “Blade position” and “blade height” are used in the discussion below to refer to the position or height of the blade with respect to the ground on which the bulldozer is supported and the angle of the blade with respect to the chassis and with respect to the horizon. If the crawler-tractor chassis pitches forward, lowering the front of the chassis closer to the ground, the automatic pitch control system disclosed herein raises the blade with respect to the dropping front of the dozer to maintain a relatively constant blade height with respect to the ground. If the chassis pitches backward, raising the front of the chassis, the system lowers the blade to maintain a relatively constant blade height with respect to the ground.
[0022] Referring to FIG. 1 , a dozer 100 is illustrated. The dozer includes a chassis 102 and an engine 104 fixed to the chassis 102 . Dozer 100 also includes left side and right side drive systems 106 , each of which further includes a drive wheel 108 that is driven by engine 104 and an endless track 110 that is coupled to and driven by the drive wheel. Dozer 100 also includes a laterally extending blade 112 that is mounted to a left arm 114 and a right arm 116 . The arms are pivotally coupled to the chassis at their rear ends and are supported at their front ends by left and right hydraulic lift cylinders 118 , 120 .
[0023] The left and right cylinder portions 122 of the hydraulic lift cylinders are coupled to the chassis and the left and right rod ends 124 are coupled to the left and right arms. When the operator retracts cylinders 118 , 120 , they shorten in length and lift blade 112 . Dozer 100 has an operator's compartment or cab 126 from which the operator operates dozer 100 . Among other controls, the cab includes an operator input device 128 that the operator manipulates to raise and lower blade 112 .
[0024] Device 128 preferably includes a lever 130 having a neutral central position. The operator can move the lever in one direction from neutral to raise the blade and can move the lever in the other direction to lower the blade.
[0025] FIG. 2 shows blade pitch control system 132 in detail. System 132 includes a blade position sensor 134 , an electronic controller 136 that is coupled to device 128 , a speed sensor 138 , a pilot hydraulic valve 140 , a main hydraulic valve 142 . System 132 also includes an operator switch 144 that is coupled to controller 136 .
[0026] Electronic controller 136 is a digital microprocessor-based controller, having a RAM, ROM, CPU, sensor input and signal conditioning circuits, valve driver circuits, and serial communications circuits. The sensors and switches are coupled to the sensor input and signal conditioning circuits, the pilot valve is coupled to the valve driver circuits and other digital controllers are coupled to the serial communications circuit. The ROM stores the CPU instructions that constitute the program, the RAM provides working space for the CPU to store values that change during operation, and the CPU executes the program instructions stored in ROM. All these components are coupled together by a data, address and control bus in a conventional manner.
[0027] Device 128 preferably includes a variable resistor or shaft encoder coupled to lever 130 to provide a signal proportional to (and indicative of) lever position. This signal is provided to controller 136 on the signal line coupling the two. Lever 130 is mounted to pivot about a pivotal axis when grasped and deflected by the operator.
[0028] Lever 130 is preferably spring loaded such that it returns to a central neutral position when released by the operator. In this way, movement in one direction away from the neutral position is identified by controller 136 as a request to raise blade 112 and movement in the other direction is identified by controller 136 as a request to lower blade 112 .
[0029] Speed sensor 138 is coupled to wheel 108 to provide a signal indicative of wheel speed and vehicle speed. Sensor 138 may be a Hall Effect device, shaft encoder, or other device configured to indicate the rotational speed and direction (velocity) of wheel 108 or the speed of the vehicle.
[0030] Pilot hydraulic valve 140 includes a coil 146 that is coupled to the valve driver circuit of controller 136 . Valve 140 is a proportional control valve that regulates flow in both directions through valve 140 . The output of pilot valve 140 is applied to both ends of main hydraulic valve 142 . The output of valve 140 opens valve 142 proportional to the magnitude and direction of the signal applied to coil 146 of valve 140 . Thus, the greater the signal applied to coil 146 , the faster the movement of blade 112 . In a preferred arrangement, a bulldozer can be retrofitted with a blade pitch control system such as that described herein, by coupling pilot hydraulic valve 140 to an existing bulldozer blade control system to that bulldozer's existing main hydraulic valve 142 . In this manner, the operator can use the bulldozer's existing blade control input devices to drive the bulldozer's existing valve 142 and control the bulldozer blade position, or the operator can release those controls (which may be electrical, mechanical, fluidic or a combination of any of the three) and control the blade using the blade control system described herein.
[0031] The movement of the valves (and hence the blade) is a function not just of the magnitude of the applied signal but also the direction of the signal. If the signal is applied in one direction, the blade moves upward. If the signal is applied in the opposite direction, the blade moves downward.
[0032] Blade movement is therefore proportional to, and in the direction indicated by, the electrical signal which controller 136 applies to coil 146 .
[0033] Blade position sensor 134 provides a signal indicative of the position of the blade—preferably, the angle of the blade or the rate of change of the blade angle as it pitches forward and backward. Blade position sensor 134 preferably includes an angular or rotational turning rate sensor, a sensor that senses the rate of rotation about an axis. Such sensors include, for example, pitch, yaw, or roll rate sensors. In the preferred embodiment, the sensor is fixed to the side-to-side center of the blade and is responsive to the pitching of the bulldozer blade about a lateral (side-to-side) axis.
[0034] Whenever the blade is either raised or lowered with respect to the chassis, the entire blade rotates about a lateral axis defined by the trailing ends of the two arms that support the blade. The trailing ends of these arms are rotationally coupled to the chassis of the crawler-tractor. Whenever the hydraulic lift cylinders are extended or retracted, the blade, in effect, rotates about a generally horizontal and lateral axis defined by the pivot points where the bulldozer arms are coupled to the chassis.
[0035] Similarly, whenever the chassis itself pitches forward or backward going over a stump or rock, for example, the blade also rotates about the generally horizontal and lateral axis.
[0036] In both of these cases, the position sensor is mounted to the blade to sense the blade's angular rotation about a lateral axis and transmits a signal indicative of this movement to controller 136 . Whether the blade tilts (i.e. rotates) forward and moves downward toward the ground or tilts (i.e. rotates) backward and moves away from the ground due to (1) extending or retracting the hydraulic lift cylinders or (2) because the chassis of the vehicle pitches, makes no difference: the effect is the same. The angular rotation of the blade with respect to a lateral axis is proportional to the blade's height. Thus, the height of the blade can be maintained in a generally constant position by maintaining the blade at a constant angle of tilt or pitch.
[0037] If the blade position sensor 134 is a rate sensor, its rate of rotation signal may be integrated by (or at) the sensor itself to provide an absolute position signal. Alternatively, the signal may be transmitted to controller 136 as a rate of rotation signal and integrated by (or at) controller 136 to provide a signal that indicates absolute blade position (angle).
[0038] Operator switch 144 has an “off” and an “on” position. When the switch is in the “on” position, the switch signals controller 136 to automatically reduce blade pitching. When switch 144 is in the “off” position, the switch signals to controller 136 that the controller should not automatically reduce blade pitching. Alternatively, the system can include a gyro rate control. The gyro rate control can be used to adjust sensitivity.
[0039] When the operator switch is in the “off” position, however, direct control of blade 112 position is possible by operator manipulation of device 128 by lever 130 . Controller 136 applies a signal to coil 146 proportional to and in the direction indicated by the movement of lever 130 of input device 128 . When the controller senses that the operator has moved lever 130 in the “R” direction, controller 136 signals coil 146 to raise the blade at a speed proportional to the deflection of lever 130 in the R” direction. When the controller senses that the operator has moved lever 130 in the “L” direction, controller 136 signals coil 146 to lower the blade at a speed proportional to the degree of deflection of lever 130 in the “L” direction. Thus, when switch 144 is “off”, controller 136 is configured to move the blade up-and-down at a rate that corresponds to the degree of deflection of lever 130 . In this mode, lever 130 signals the rate at which blade 112 rises and falls
[0040] When the operator switch is in the “on” position, controller 136 controls blade pitching by monitoring the blade's angular position with sensor 134 and driving the blade up or down with valve 140 , to keep it at a generally constant angle with respect to the earth. This automatic pitch control is described below in conjunction with FIGS. 3 and 4 .
[0041] When the switch is in the “on” position, controller 136 operates, generally, by (1) receiving signals indicative of blade position from blade position sensor 134 , (2) receiving signals indicative of a preferred or target blade position from device 130 and (3) combining the two signals to keep blade 112 at the preferred or target position.
[0042] Controller 136 determines the operator's preferred blade position from the signals that are provided by input device 128 . It compares that position with the actual blade position and, based upon the difference between the two, drives the blade to the target position. It does this by controlling pilot valve 140 , which in turn controls main valve 142 , which in turn controls hydraulic lift cylinders 118 , 120 , which in turn raise and lower blade 112 with respect to the crawler-tractor.
[0043] Control system 132 is coupled to a source of hydraulic fluid 148 . This source includes a hydraulic pump that is driven by the bulldozer's engine. The system is also coupled to a hydraulic fluid reservoir 150 to which fluid is returned. The source 148 and reservoir 150 are coupled to the valves to provide the hydraulic fluid used to operate the valves and the hydraulic cylinders.
[0044] The components described above, including the blade position sensor 134 , the electronic controller 136 , operator input device 128 , speed sensor 138 , pilot hydraulic valve 140 , main hydraulic valve 142 , and operator switch 144 , collectively constitute pitch control system 132 .
[0000] Primary Pitch Control Mode
[0045] FIG. 3 is a flow chart illustrating the programming of controller 136 and the operation of the blade pitch control system. Controller 136 is configured to execute the steps shown in FIG. 3 whenever the operator switch 144 is in the “on” position. The steps shown in FIG. 3 are repeated by controller 136 on a preferred interval of 10 to 100 milliseconds.
[0046] In the first step 152 of FIG. 3 , controller 136 reads the signal from the input device 128 , which indicates whether the operator is requesting that the blade be raised, lowered, or held in the same position. In step 154 , controller 136 checks the signal from input device 128 to see if lever 130 is in neutral. Due to its spring loading, lever 130 remains in its neutral position until the operator moves it to another position and returns to neutral when released.
[0047] If the lever is in neutral, the process continues to step 156 , if is not in neutral, controller 136 continues to step 158 . In step 158 , controller increments or decrements “TARGET”, a digital value stored in the memory of controller 136 (and identified herein for convenience as “TARGET”) that indicates the operator's preferred or target position for blade 112 .
[0048] Controller 136 increments TARGET if the operator has moved lever 130 in the “raise” (“R” in FIG. 2 ) direction from the neutral position (“N” in FIG. 2 ). Controller 136 increments TARGET an amount proportional to the distance that lever 130 is deflected in the “raise” direction. Controller 136 decrements TARGET if the operator has moved lever 130 in the “lower” (“L” in FIG. 2 ) direction from the neutral position. Controller 136 decrements TARGET an amount proportional to the distance that lever 130 is deflected in the “lower” direction.
[0049] Once controller 136 has changed TARGET, processing continues with step 156 . In step 156 , controller 136 reads the signal from the blade position sensor 134 . This signal generally indicates the actual position of the blade with respect to the ground. Controller 136 then stores the value of this signal in a memory location in controller 136 identified for convenience herein as “ACTUAL” herein. Whenever the vehicle pitches forward, the blade both moves downward and tilts forward at the same time. Whenever the blade is lowered using hydraulic lift cylinders 118 , 120 , the blade is not only lowered but also tilted forward. In both cases, the angle of the blade indicates the blade's position.
[0050] Having read the signal from sensor 134 in step 156 , controller 136 proceeds to step 160 , which represents the feedback control loop executed by controller 136 for controlling the position of blade 112 . In step 160 , controller compares the actual position of the blade derived from the signal of sensor 134 to the target position of the blade provided by the value TARGET stored in the controller's memory circuits. If the blade is not at the target position (TARGET), controller 136 is programmed to open pilot valve 140 an amount appropriate to incrementally move the blade back to its target position.
[0051] As the blade moves back toward its target position with each iteration of the steps of FIG. 3 , the actual blade position (ACTUAL) that controller 136 reads in step 156 gets closer and closer to the target position (TARGET). This process is called “feedback control” and the repeated iterations through steps 156 and 160 are called a “feedback control loop” or “feedback control algorithm”. They are called this since (1) the controller repeatedly loops through the steps and (2) the process relies upon feedback from the physical system being controlled (i.e. the position of the blade and hence the signal from sensor 134 ) to determine the appropriate control actions to be taken. In this example, the control action taken by controller 136 is closing or opening valve 140 .
[0052] FIG. 4 is a control diagram of the PID (proportional-integral-derivative) feedback control loop executed by controller 136 .
[0053] While this particular control loop is representative of a typical feedback control algorithm, it should be understood that it is just one of many automatic feedback control algorithms that may be used to control blade position. The selection of an appropriate feedback control algorithm depends upon many factors, including the particular size, shape, and mass of the structures being controlled (e.g. the blade 112 and the arms); the configuration and capacity of the devices controlling them (e.g. the hydraulic valves 140 , 142 and cylinders 118 , 120 ); and the speed, resolution, and accuracy of the sensors and instrumentation (e.g. blade position sensor 134 ).
[0054] The control loop of FIG. 4 is preferably implemented in software, in which the control loop items shown in FIG. 4 are programming constructs. In the control diagram, the target blade position, “TARGET”, ( 162 ) is summed at junction 164 with the actual blade position, “ACTUAL”, ( 166 ) provided by sensor 134 to provide an error signal on line 168 . This error signal is provided to a proportional gain block 170 , a differential block 172 and an integral block 174 .
[0055] The blade position can be expressed in absolute terms or in relative terms as an angle or a distance. The units used by controller 136 are immaterial. What is important is that whatever units are used, the blade position (height or angular rotation) be kept generally constant in the vicinity of TARGET.
[0056] The proportional block generates an output on line 176 that is proportional to the error signal. The derivative block generates an output on line 178 that is proportional to the derivative of the error signal (the time rate of change of the error signal), and the integral block generates an output on line 180 that is proportional to the integral of the error signal (the sum of the errors over time). Summing junction 181 combines the proportional, the integral, and the derivative components of the signal and provides that combined signal on line 182 . The combined signal is then applied to pilot valve 140 (block 184 ). When pilot valve 140 changes its position, it changes the position of main hydraulic valve 142 (block 186 ), which changes the position of blade 112 (block 188 ), by moving it up or down. When blade 112 changes position, it moves position sensor 134 (block 190 ) which is coupled to the blade. Sensor 134 responds accordingly by generating a signal indicating the new actual position (ACTUAL) of the blade.
[0057] To summarize the operation of the automatic pitch control system shown in FIGS. 3 and 4 , the system has a preferred or target blade position (TARGET) to which it constantly drives the blade.
[0058] Whenever the chassis of the vehicle pitches forward, the blade position sensor 134 senses the forward rotation (or pitching) of the blade about a lateral axis as the blade drops towards the ground. Controller 136 executes a feedback control loop to correct the blade's position using the hydraulic valves and the hydraulic lift cylinders to retract the hydraulic cylinders and to lift the blade upward. This has a double effect of maintaining the blade at a generally constant angle of tilt and maintaining the blade at a generally constant height relative to the earth.
[0059] Similarly, when the vehicle's chassis pitches backwards, it causes the blade to tilt backwards and the blade to lift higher above the ground. Blade position sensor 134 senses this backwards rotation of the blade of and signals controller 136 . Controller 136 , in turn, executes the feedback control loop to correct the blade's position by extending the hydraulic cylinders and lowering the blade downward toward the ground. This also has the double effect of maintaining the blade at a generally constant angle of tilt with respect to the earth and maintaining the blade at a generally constant height with respect to the earth.
[0060] The operator can change the target blade position by moving lever 130 . Whenever the target blade position changes, the control loop executed by controller 136 responds by automatically controlling the position of the blade.
[0061] When the operator switch is in the “off” position, controller 136 commands the valves to open (and hence the blade to move) in a direction proportional to the degree of deflection of lever 130 from its neutral position. If the bulldozer chassis pitches when the operator switch is in the “off” position, the hydraulic cylinders do not move with respect to the chassis. The blade pitches just as the chassis pitches, either digging deeper into the ground when the chassis pitches forward or rising up out of the ground when the chassis pitches backward.
[0000] Automatic TARGET Determination
[0062] In the example illustrated above, the target position of the blade is selected manually by the operator who can change the target blade position at any time by operating the input device. However, in an alternative mode of operation, controller 136 is configured to automatically determine the initial blade position in automatic pitch control mode based upon the average blade position during manual operation.
[0063] In this alternative mode of operation, controller 136 is configured to periodically read the actual position of the blade from sensor 134 during manual operation of the bulldozer (i.e. when switch 144 is turned off). During this manual operation, the operator gradually adjusts the blade position over time with input device 128 until he finds the optimum blade position.
[0064] As the operator adjusts the blade during manual operation, controller 136 is configured to automatically read successive blade positions (i.e. the blade position signal) over a period of time. Controller 136 is configured to average these successive signals to determine an average actual blade position. Controller 136 is therefore aware of the operator's desired blade position even before the operator turns the blade pitch control system “on”. Once the operator engages the blade pitch control system by turning switch 144 “on”., controller 136 already knows the current height of the blade and can immediately take over and keep the blade at that height.
[0065] Once the pitch control system is turned on, controller 136 uses the position it calculated during manual mode as its initial target blade position (TARGET). Thus, from the moment the operator turns the automatic pitch control system “on”, controller 136 starts controlling the blade position to keep the blade at the same position that the operator was manually keeping it.
[0000] Alternative Pitch Control Mode
[0066] In the example illustrated in FIGS. 34 above, the target position of the blade is changed by the operator whenever the operator manipulates input device 128 . In the automatic pitch control mode, whenever the operator moves lever 130 up or down, the target blade position (TARGET) changes up or down, responsively.
[0067] In an alternative configuration, however, controller 136 is configured to change the target position (TARGET) when the input device is moved in one direction, but not to change the target position when the operator moves the lever in the other direction. In this mode, whenever the operator moves lever 130 in the “L” (or “lower”) direction, for example, controller 136 responds by lowering the target position (TARGET) of the blade. Controller 136 continues controlling blade pitching, but does so with a new and lower target blade position.
[0068] When the operator moves lever 130 of input device 128 in the “R” or “raise” direction, however, controller 136 is configured to not change (i.e. to not raise) the target blade position. Instead, controller 136 raises the blade as though the switch 144 was “off”, and temporarily ceases to automatically control blade position. Controller 136 remembers the target blade position, however, and does not change it. Controller 136 just ceases to drive the blade to the target position until the operator again signals his desire for automatic blade pitch control.
[0069] In this alternative configuration, controller 136 interprets the operator's upward movement of lever 130 not as a request to raise or increase the target blade position, but as a request to (1) temporarily raise the blade to avoid obstructions, and (2) temporarily disable automatic pitch control until the obstruction is passed.
[0070] The operator can continue through the field for any distance with the blade held by controller 136 in this raised position. Controller 136 will not begin automatically controlling blade pitch again until the operator signals controller 136 to restart automatic control using lever 130 in a special manner.
[0071] In this way the operator does not have to turn the automatic pitch control “off” with switch 144 , then raise the blade, then wait for the obstruction to pass, then turn the automatic blade pitch control “on” again with switch 144 when he wishes to return to automatic pitch control at the original height.
[0072] The operator signals his desire to restart automatic blade pitch control in a manner opposite the way he signaled his desire to leave automatic blade pitch control.
[0073] When the operator wishes to turn automatic blade pitch control back on in this alternative configuration, he moves lever 130 in the “L” (lower) direction (again, without manipulating switch 144 ). Controller 136 responds to this lever movement in the “L” direction by lowering the blade just as it does when switch 144 is “off” and without changing the target blade position.
[0074] With the operator holding lever 130 in the “L” position, the controller begins to lower the blade toward its target blade position. The blade eventually drops to the target blade position. Controller 136 is aware of this approach toward the target blade position since controller 136 is configured to continuously monitor the actual blade position during this blade descent. As the blade descends, controller 136 is configured to compare the actual blade position with the (lower) target blade position.
[0075] Eventually controller 136 determines that the blade is within a small and predetermined distance of the target blade position. At this point, controller 136 stops functioning as though switch 144 is “off”, and restarts its automatic control of blade position.
[0076] Once controller 136 has restarted its automatic control of blade position, if the operator releases lever 130 of input device 128 the controller merely continues automatically controlling the blade position.
[0077] Alternatively, if the operator does not release lever 130 but keeps holding it in the “L” position once automatic control has been reengaged, controller 136 does not keep lowering the blade, but controls the blade height at the target blade position.
[0078] To summarize the operation in this alternative automatic pitch control mode, the operator can lower the target blade position with lever 130 , but cannot raise the target blade position by moving lever 130 in the “raise” direction. Instead, when the operator raises the lever that signals controller 136 to (1) raise blade 112 above the target blade position and (2) immediately stop moving the blade just as though the blade pitch control is disabled when the operator releases lever 130 . The purpose of this operating mode is to permit the operator to briefly raise the blade above stumps, rocks, or other protrusions, to temporarily disable automatic blade positioning without changing the target blade height and to permit restarting of automatic blade pitch control without having to manipulate switch 144 .
[0079] Assuming the operator wishes to lower the blade further (i.e. below the current target blade position the controller 136 has locked onto), the operator must first release lever 130 , permitting it to return to the neutral position. This return to neutral is immediately sensed by controller 136 .
[0080] Once controller 136 senses the blade had returned to neutral, it keeps controlling the blade position automatically, but permits the operator to (1) lower the blade and the target blade position by moving the lever in the “L” direction, or (2) raise the blade above the target blade position by moving the lever in the “R” direction. If the operator wishes to keep lowering the blade in the automatic mode once the controller has “locked on”, he must first release the lever. In another alternative embodiment, when the operator lowers the blade to within the small and predetermined distance of the target blade position, the system does not automatically begin controlling blade position at the target blade height before the operator releases the lever, but waits until the operator releases the lever, permitting it to return to its neutral position.
[0081] In another alternative embodiment, the speed sensor senses the vehicle's speed through the field and provides it to controller 136 . Controller 136 , in turn, changes the response rate of its PID control loop to respond faster when the vehicle is moving faster through the field, and to respond slower when the vehicle is moving slower through the field.
[0082] In yet another alternative embodiment, a GPS can be coupled to controller 136 to provide location information to controller 136 that could provide better information on the vehicle's path through the field.
[0083] It will be understood that changes in the details, materials, steps, and arrangements of parts which have been described and illustrated to explain the nature of the invention will occur to and may be made by those skilled in the art upon a reading of this disclosure within the principles and scope of the invention.
[0084] For example, rather than providing a blade position sensor that is responsive to the blade being raised and lowered and responsive to the blade pitching about a substantially lateral axis, a blade position sensor can be provided that is responsive to rotating about a longitudinal axis, or “rolling”. In this case, the blade position sensor would sense the rolling of the blade about a longitudinal axis such as occurs when one side of the bulldozer is raised above the other side. This happens, for example, when the track on one side of the bulldozer runs over our rock or a stump. Many bulldozers are configured with hydraulic cylinders coupled to the blade that control the blade's roll angle. These hydraulic cylinders cause one side of the blade to raise and the other side of the blade to lower. In this arrangement, if the chassis begins to roll to the right, with the left side tracks being lifted higher above the ground than the right side tracks, controller 136 will sense the corresponding rolling of the blade to the right by monitoring this alternative or additional blade position sensor that senses rotation about the blade's longitudinal axis. Using the same control algorithm described above with regard to bulldozer pitching, controller 136 is configured to maintain the roll angle of the blade constant.
[0085] In a second alternative arrangement, a blade control system can be provided with a blade position sensor responsive to rotation about a longitudinal axis and rotation about a lateral axis (such as illustrated herein). In this arrangement, electronic controller 136 could be coupled to both of these blade position sensors, and could be configured to execute two PID control loops, one controlling rotation around the longitudinal axis and the other controlling rotation around the lateral axis. In effect, controller 136 would control the height of the blade as well as its left to right tilt angle.
[0086] The position sensor is shown as a single physical device coupled to the center of the blade of the bulldozer. In an alternative embodiment, the position sensor 134 may be located elsewhere, such as a long the dozer arms, or it may comprise two physical devices, one device to provide chassis position and one disposed to provide a position signal indicative of the difference between the chassis position and the blade's position. These two devices may include a position sensor, such as item 134 , coupled to the dozer chassis and an angle sensor coupled between the blade and the chassis to provide a chassis-to-blade angle signal. By combining signals from these two physical devices, one showing or indicating the dozer chassis position with respect to the ground, and the other showing or indicating the position of the blade with respect to the chassis, the system described herein would function just as well.
[0087] The foregoing description illustrates the preferred embodiment of the invention; however, concepts, as based upon the description, may be employed in other embodiments without departing from the scope of the invention. Accordingly, the following claims are intended to protect the invention broadly as well as in the specific form shown.
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A dozer blade control system controls the position of a bulldozer blade, maintaining the blade at a constant position as the dozer travels through a worksite. The control system monitors the angle of the dozer blade with respect to the earth and when it senses that the dozer blade is tilting, it corrects the dozer blade's position by extending or retracting hydraulic cylinders that couple the dozer blade to the chassis of the crawler-tractor. When the dozer chassis pitches forwards, the blade begins to tilt forward and to drop closer to the ground. The control system senses this forward rotation of the blade and retracts the hydraulic cylinders that couple the blade to the chassis, causing the blade to return to and maintain its original position. Conversely, when the dozer chassis pitches backwards and the blade begins to tilt backward and rise higher above the ground, the control system extends the hydraulic cylinders coupling the blade to the chassis and lowers the blade, causing the blade to return to and maintain its original position with respect to the earth.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 61/348,724, filed May 26, 2010, the contents of which are incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
This invention was made with government support by National Institutes of Health (NIH) grant GM075159.
BACKGROUND OF THE INVENTION
The present invention generally relates to the use of the arrestin-2/STAM-1 complex as a therapeutic target, for example, to identify and develop pharmacological agents capable of treating medical diseases, such as the treatment of metastasis in cancer patients and myocardial infarction.
Chemokines are a family of small cytokines, or proteins, that are secreted by cells of certain organisms, and in particular the cells of all vertebrates. Chemokines interact with G protein-linked transmembrane receptors, or chemokine receptors, found on the surfaces of their target cells. Of interest to the present invention are the CXC family of chemokines (α-chemokines), and in particular the CXC chemokine receptors (CXCR) to which CXC chemokines bind.
The CXC chemokine receptor 4 (CXCR4), a G protein-coupled receptor (GPCR), upon activation by its cognate ligand stromal-cell derived factor-1α (SDF-1α/CXCL12), is known to be rapidly internalized and targeted into the degradative pathway by a ubiquitin-dependent mechanism. See Marchese, A., and Benovic, J. L., Agonist-promoted ubiquitination of the G protein-coupled receptor CXCR4 mediates lysosomal sorting, J. Biol. Chem. 276, 45509-45512 (2001); Shenoy, S. K., McDonald, P. H., Kohout, T. A., and Lefkowitz, R J., Regulation of receptor fate by ubiquitination of activated beta 2-adrenergic receptor and beta-arrestin, Science 294, 1307-1313 (2001); and Marchese, A., Raiborg, C., Santini, F., Keen, J. H., Stenmark, H., and Benovic, J. L., The E3 ubiquitin ligase AIP4 mediates ubiquitination and sorting of the G protein-coupled receptor CXCR4, Dev. Cell 5, 709-722 (2003). Activation by CXCL12 induces rapid and transient phosphorylation of serine residues 324 and 325 within the carboxyl-terminal tail (C-tail) of CXCR4, thereby promoting binding to the E3 ubiquitin ligase atrophin-I interacting protein 4 (AIP4) via a novel WW-domain mediated interaction culminating in ubiquitination of vicinal lysine residues (Marchese et al. (2003); Bhandari, D., Robia, S. L., and Marchese, A., The E3 ubiquitin ligase atrophin interacting protein 4 binds directly to the chemokine receptor CXCR4 via a novel WW domain-mediated interaction, Mol. Biol. Cell. 20, 1324-1339 (2009)). This is followed by internalization of CXCR4 onto early endosomes where the ubiquitin moiety serves as a sorting signal to direct the receptor to lysosomes for proteolysis (Marchese and Benovic (2001); Marchese et al. (2003)).
In general, the ubiquitin moiety on ubiquitinated receptors interacts with ubiquitin binding domains (UBD) found in several proteins of the endosomal sorting complex required for transport (ESCRT) machinery (Raiborg, C., and Stenmark, H., The ESCRT machinery in endosomal sorting of ubiquitylated membrane proteins, Nature 458, 445-452 (2009); Shields, S. B., Oestreich, A. J., Winistorfer, S., Nguyen, D., Payne, J. A., Katzmann, D. J., and Piper, R., ESCRT ubiquitin-binding domains function cooperatively during MVB cargo sorting, J. Cell Biol. 185, 213-224 (2009)). The ESCRT machinery is made up of four distinct protein complexes (ESCRT 0-III) that act in a sequential and coordinated manner to target ubiquitinated receptors into multivesicular bodies, which then fuse with lysosomes where degradation occurs. Recruitment into this pathway takes place by the initial recognition of the ubiquitinated receptor by ESCRT-0, which then subsequently recruits ESCRT-I to the endosomal membrane, followed by recruitment of ESCRT II and III, culminating in proper execution of the sorting process (Williams, R. L., and Urbe, S., The emerging shape of the ESCRT machinery, Nat. Rev. Mol. Cell Biol. 8, 355-368 (2007); Raiborg and Stenmark (2009)). Hepatocyte growth factor-regulated tyrosine kinase substrate (HRS) is understood to be a critical element of ESCRT-0 and has been shown to mediate down regulation of several cell surface signaling receptors (Bache, K. G., Brech, A., Mehlum, A., and Stenmark, H., Hrs regulates multivesicular body formation via ESCRT recruitment to endosames, J. Cell Biol. 162, 435-442 (2003); Kanazawa, C., Morita, E., Yamada, M., Ishii, N., Miura, S., Asao, H., Yoshimori, T., and Sugamura, K., Effects of deficiencies of STAMs and Hrs, mammalian class E Vps proteins, on receptor downregulation, Biochem. Biophys. Res. Commun. 309, 848-856 (2003); Abella, J. V., Peschard, P., Naujokas, M. A., Lin, T., Saucier, C., Urbe, S., and Park, M., Met/Hepatocyte growth factor receptor ubiquitination suppresses transformation and is required for Hrs phosphorylation, Mol. Cell Biol. 25, 9632-9645 (2005); Hasdemir, B., Bunnett, N. W., and Cottrell, G. S., Hepatocyte growth factor-regulated tyrosine kinase substrate (HRS) mediates post-endocytic trafficking of protease-activated receptor 2 and calcitonin receptor-like receptor, J. Biol. Chem. 282, 29646-29657 (2007)). One such cell surface signaling receptor is CXCR4 (Marchese et al. (2003)). The ubiquitin moiety on CXCR4 is thought to interact with the ubiquitin interacting motif (UIM) found in HRS, thereby targeting CXCR4 into the degradative pathway.
Together with HRS, signal-transducing adaptor molecule (STAM) forms ESCRT-O, STAM was originally identified as an adaptor protein involved in cytokine signaling (Takeshita, T., Arita, T., Asao, H., Tanaka, N., Higuchi, M., Kuroda, H., Kanecko, K., Munakata, H., Endo, Y., Fujita, T., and Sugamura, K.; Cloning of a novel signal-transducing adaptor molecule containing an SH3 domain and ITAM, Biochem, Biophys, Res. Commun. 225, 1035-1039 (1996); Takeshita, T., Arita, T., Higuchi, M., Asao, H., Endo, K., Kuroda, H., Tanaka, N., Murata, K., Ishii, N., and Sugamura, K.; STAM, signal transducing adaptor molecule, is associated with Janus kinases and involved in signaling for cell growth and c-myc induction, Immunity 6, 449-457; (1997). Two STAM isoforms exist, STAM-1 and STAM-2, which share 53% amino acid identity and may be redundant in their function (Lohi, O., Poussu, A., Merilainen, J., Kellokumpu, S., Wasenius, V. M., and Lehto, V. P., EAST, an ipidermal growth factor receptor- and Eps 15-associated protein with Src homology 3 and tyrosine-based activation motif domains, J. Biol. Chem., 273, 21408-21415 (1998); Endo, K., Takeshita, T., Kasai, H., Sasaki, Y., Tanaka, N., Asao, H., Kikuchi, K., Yamada, M., Chenb, M., O'Shea, J. J., and Sugamura, K., STAM2, a new member of the STAM family, bindign to the Janus kinases, FEBS Lett, 477, 55-61 (2000); Pandey, A., Fernandez, M. M., Steen, H., Blagoev, B., Nielsen, M. M., Roche, S., Mann, M., and Lodish, H. F., Identification of a novel immunoreceptor tyrosine-based activation motif-containing molecule, STAM2, by mass spectrometry and its involvement in growth factor and cytokine receptor signaling pathways, J. Biol. Chem., 275, 38633-38639 (2000); Yamada, M., Ishii, N., Asao, H., Murata, K., Kanazawa, C., Sasaki, H., and Sugamura, K., Signal-transducing adaptor molecules STAM1 and STAM2 are required for T-cell development and survival, Mol. Cell Biol., 22, 8648-8658 (2002). Similar to HRS, STAM also binds to ubiquitin and may act in concert with HRS to recruit ubiquitinated receptors for lysosomal sorting (Asao, H., Sasaki, Y., Arita, T., Tanaka, N., Endo, K., Kasai, H., Takeshita, T., Endo, Y., Fujita, T., and Sugamura, K., Hrs is associated with STAM, a signal-transducing adaptor molecule, Its suppressive effect on cytokine-induced cell growth, J. Biol. Chem., 272, 32785-32791 (1997); Takata, H., Katao, M., Denda, K., and Kitamura, N., A hrs binding protein having a Src homology 3 domain is involved in intracellular degradation of growth factors and their receptors, Genes Cells 5, 57-69 (2000); Bache, K. G., Raiborg, C., Mehlum, A., and Stenmark, H., STAM and Hrs are subunits of a multivalent ubiquitin-binding complex on early endosomes, J. Biol. Chem., 278, 12513-12521 (2003b); Kanazawa et al., (2003). STAMs may also modulate endosomal sorting by virtue of their ability to interact with endosomal associated deubiquitinating enzymes AMSH (associated molecule with the SH3 domain of STAM) and UBPY, which may modulate the ubiquitination status of both receptors and/or the sorting machinery (McCullough, J., Clague, M. J., and Urbe, S., AMSH is an endosome-associated ubiquitin isopeptidase, J. Cell Biol., 166, 487-492 (2004); Bowers, K., Piper, S. C., Edeling, M. A., Gray, S. R., Owen, D. J., Lehner, P. J., and Luzio, J. P., Degradation of endocytosed epidermal growth factor and virally ubiquitinated major histocompatibility complex class I is independent of mammalian ESCRTII, J. Biol. Chem., 281, 5094-5105 (2006); McCullough, J., Row, P.e., Lorenzo, O., Doherty, M., Beynon, R., Clague, M. J., and Urbe, S., Activation of the endosome-associated ubiquitin isopeptidase AMSH by STAM, a component of the multivesicular body-sorting machinery, Curr. Biol., 16, 160-165 (2006); Row, P. E., Prior, L. A., McCullough, J., Clague, M. J., and Urbe, S., The ubiquitin isopeptidase UBPY regulates endosomal ubiquitin dynamics and is essential for receptor down-regulation, J. Biol. Chem., 281, 12618-12624 (2006); Kong, C., Su, X., Chen, P. I., and Stahl, P. D., Rin1 interacts with signal-transducing adaptor molecule (STAM) and mediates epidermal growth factor receptor trafficking and degradation, J. Biol. Chem., 282, 15294-15301 (2007); Ma, Y. M., Boucrot, E., Villen, J., Affar el, B., Gygi, S. P., Gottlinger, H. G., and Kirchhausen, T., Targeting of AMSH to endosomes is required for epidermal growth factor receptor degradation, J. Biol. Chem., 282, 9805-9812 (2007). Recently, STAMs have been implicated in endoplasmic reticulum to Golgi trafficking, possibly via their interaction with coat protein II proteins (Rismanchi, N., Puertollano, R., and Blackstone, C., STAM adaptor proteins interact with COPII complexes and function in ER-to-Golgi trafficking, Traffic 10, 201-217 (2009). However, their role in GPCR trafficking and signaling is believed to be relatively unknown.
It has been recently shown that arrestin-2 mediates endosomal sorting of CXCR4 (Bhandari, D., Trejo, J., Benovic, J. L., and Marchese, A., Arrestin-2 interacts with the ubiquitin-protein isopeptide ligase atrophin-interacting protein 4 and mediates endosomal sorting of the chemokine receptor CXCR4, J. Biol. Chem., 282, 36971-36979 (2007). Non-visual arrestins, arrestin-2 and arrestin-3 (also known as β-arrestin1 and β-arrestin2, respectively), are generally known for their ability to regulate GPCR desensitization, internalization and signaling (Moore, C. A., Milano, S. K., and Benovic, J. L., Regulation of receptor trafficking by GRKs and arrestins, Ann. Rev. Phy., 69, 451-482 (2007), although their role in endosomal sorting remains relatively unexplored. Arrestin-2 interacts with and co-localizes with AIP4 on early endosomes, where it targets CXCR4 for lysosomal sorting (Bhandari et al., 2007). In addition to mediating ubiquitination of CXCR4 at the plasma membrane, AIP4 also interacts with and mediates ubiquitination of HRS, likely on endosomes. However, the function of the ubiquitin moiety remains unknown (Marchese et al., 2003). How arrestin-2 may integrate with AIP4 and HRS to carry out CXCR4 sorting into the degradative pathway remains poorly understood.
It is believed that others have used pharmacological agents that directly target CXCR4 to antagonize agonist (CXCL12) evoked CXCR4 signaling mediated events. A major disadvantage of this approach is that directly targeting CXCR4 is not specific, as it would modulate all intracellular signaling cascades activated by CXCR4. A major caveat with this approach is that it has the potential of producing unintended consequences, such as deleterious side-effects.
BRIEF DESCRIPTION OF THE INVENTION
The present invention provides methods of utilizing the arrestin-2/STAM-1 complex as a therapeutic target.
According to a first aspect of the invention, a method is provided that includes treating cells of a living organism to mediate an interaction between an arrestin-2 adapter protein molecule and a STAM-1 adapter protein molecule, wherein the interaction is characterized by the arrestin-2 adapter protein molecule directly binding to the STAM-1 adapter protein molecule. The treatment preferably involves subjecting a cell of the living organism to a pharmacological agent, and then determining whether the pharmacological agent modulates, for example, disrupts or enhances, the interaction between the arrestin-2 adapter protein molecule and the STAM-1 adapter protein molecule.
According to a second aspect of the invention, a method is provided that involves identifying a pharmacological agent to treat metastasis of a cancer in living organisms. The method includes treating cells of a living organism with the pharmacological agent, and then determining whether the pharmacological agent disrupts an interaction (binding) between an arrestin-2 adapter protein molecule and a STAM-1 adapter protein molecule of cells of the living organism. If the pharmacological agent disrupts the interaction, the method may further entail treating a second living organism with the pharmacological agent to treat metastasis of a cancer in the second living organism, for example, by decreasing CXCR4 levels and/or inhibiting CXCL12-evoked cell migration in the second living organism.
A technical effect of the invention is the ability to interact arrestin-2 with the ESCRT machinery to modulate endosomal sorting of CXCR4. In particular, an interaction between the adaptor proteins arrestin-2 and STAM-1 has been identified that enables the arrestin-2/STAM-1 complex to be used as a therapeutic target to modulate CXCR4 levels and to modulate CXCL12-evoked cell migration, which can be extended to use of the arrestin-2/STAM-1 complex to identify and develop novel pharmacological agents capable of targeting the arrestin-2/STAM-1 interaction for therapeutic intervention. In a particular example, the arrestin-2/STAM-1 interaction may be blocked or otherwise disrupted, which can have therapeutically beneficial effects, for example, in the treatment of metastasis in cancer patients, and particularly cancers that have elevated levels of CXCR4 in the tumor cells.
Data obtained from investigations leading to the invention have indicated that the arrestin-2/STAM-1 complex serves to negatively regulate the cellular levels of CXCR4 upon activation with its cognate ligand (CXCL12), in other words, stabilizes CXCR4 levels in cells. In particular, interaction regions have been mapped between STAM-1 and arrestin-2 in both proteins, and over-expression of these regions in cells has been shown to disrupt the interaction and accelerate CXCR4 degradation. Over-expression of these regions has also been shown to inhibit CXCL12 evoked cell migration, while leaving signaling to extracellular regulated kinases 1 and 2 intact. As such, the arrestin-2/STAM-1 complex potentially represents a highly useful cellular target to decrease CXCR4 levels and to modulate cell migration by intentionally mediating the interaction between arrestin-2 and STAM-1, while leaving a subset of the intracellular signaling cascades and other functions of CXCR4 intact. As such, targeting the arrestin-2/STAM-1 complex may be particularly useful to inhibit migration of tumor cells, and thus metastasis, in patients who have cancers in which CXCR4 levels are elevated. The interface mediating the interaction between arrestin-2 and STAM-1 may be further useful as a target to develop and identify pharmacological agents that may disrupt the interaction between arrestin-2 and STAM-1, with the goal of using them as therapeutics to treat diseases in which reducing CXCR4 level/signaling and migration would be beneficial.
Prior art methods of modulating CXCR4 signaling have directly targeted CXCR4, thereby affecting all intracellular signaling pathways activated by CXCR4 and thus may have many unintended consequences. In contrast, the present invention targets the recently discovered arrestin-2/STAM-1 protein complex that shows specificity to a subset of CXCR4 related signaling and functional events. Therefore, another advantage of the invention is that side effects or unintended consequences are likely to be minimized by targeting the arrestin-2/STAM-1 complex. Also, by targeting the intracellular arrestin-2/STAM-1 complex, accelerated agonist-promoted degradation of CXCR4 occurs and cell migration can be inhibited. No other targets and/or agents that have this dual effect on CXCR4 degradation/migration are believed to be known. In addition, the capability to modulate both of these endpoints with a high degree of specificity would be particularly important outcomes for treating tumor metastasis.
The use of pharmacological agents that target the arrestin-2/STAM-1 complex may also be applicable to the treatment of other aspects related to cancer, such as tumor cell invasion, proliferation and angiogenesis. Additional potential uses of the arrestin-2/STAM-1 complex include the treatment of HIV/AIDS infection, WHIM (wart, hypogammaglobulinemia, infection, and myelokathexis) syndrome and opioid induced hyperalgesia. In each of these diseases, by targeting the arrestin-2/STAM-1 complex and enhancing CXCR4 degradation, decreased cellular levels of CXCR4 may reduce HIV infection, decrease CXCR4 signaling observed in WHIM syndrome patients and reduce pain in patients who suffer from opioid-induced hyperalgesia. In addition, targeting the arrestin-2/STAM-1 may be beneficial to treat highly metastatic cancers that are not CXCR4-dependent, such as those that have increased or amplified epidermal growth factor receptor expression.
Other potential therapeutic uses for targeting the arrestin-2/STAM-1 complex include the treatment of patients who suffer from cardiac and lung ischemia. Immediately after a cardiac ischemic event, cells in the heart release SDF-1α (the cognate ligand of CXCR4). Release of SDF-1α appears to mobilize progenitor cells in the bone marrow to travel to the ischemic site in the heart, where they initiate cardiac tissue repair in an attempt to restore cardiac function. The bone marrow-derived cells express CXCR4 and travel to the site of injury in response to the presence of SDF-1α released after the ischemic event. Increasing the mobilization of cells and improving their motility in response to SDF-1α could potentially increase the mobilization of bone marrow derived cells to the site of injury, with the potential for enhancing the repair mechanisms and benefiting individuals who suffer from cardiac ischemia following a heart attack. In that the invention identifies the arrestin-2/STAM-1 complex as a therapeutic target to modulate CXCR4 levels and CXCL12-evoked cell migration, a beneficial effect of enhancing the interaction may be the ability to improve cell mobility and increase the ability of bone marrow-derived progenitor cells to travel to the heart to initiate tissue repair. As such, while disrupting/blocking the arrestin-2/STAM-1 interaction is believed to be therapeutically beneficial for certain treatments, such as in the treatment of cancer, enhancing/promoting the interaction may be therapeutically beneficial as a treatment for cardiac ischemia.
Other aspects and advantages of this invention will be better appreciated from the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 contains representative blots from one of three ( FIG. 1A-FIG . 1 C) independent experiments, and illustrates interactions between arrestin-2 and ESCRT-0. In FIG. 1A , equimolar amounts (about 134 nM) of GST (glutathione S-transferase) immobilized on glutathione-Sepharose resin and GST-arrestin-2 were incubated with lysates from HEK293 cells transiently transfected with FLAG-STAM-1, FLAG-STAM-2 or FLAG-HRS. Bound proteins were detected by immunoblotting using the anti-FLAG M2 antibody. In FIG. 1B , equimolar amounts (about 117 nM) of GST-STAM-1, GST-STAM-2 and GST immobilized on glutathione-Sepharose resin were incubated with purified arrestin-2 (about 212 nM). Bound arrestin-2 was detected using an anti-arrestin-2 monoclonal antibody. In FIGS. 1A and 1B , blots were stripped and reprobed using an anti-GST antibody to determine the levels of the GST fusion proteins used in the binding assay. In FIG. 1C , lysates from HeLa cells either transiently transfected with HA-arrestin-2, HA-arrestin-3 or empty vector (pcDNA3) were incubated with antibodies to immunoprecipitate transfected as described below. Immunoprecipitates (IP) and lysates were analyzed by SDS-PAGE and immunoblotting as indicated.
FIG. 2 contains representative blots from one of three independent experiments, and illustrates the regulation of the arrestin-2/STAM-1 interaction with CXCR4. In FIG. 2A , HeLa cells transiently transfected with HA-arrestin-2 were serum starved as described below, followed by treatment with 30 nM CXCL12 for about thirty to about sixty minutes. Cell lysates were subject to immunoprecipitation using monoclonal anti-HA and isotype control antibodies. Immunoprecipitates and lysates were analyzed by SDS-PAGE and immunoblotting to detect endogenous STAM-1 and HA-arrestin-2. Immunoblots were subject to densitometric analysis and the bar graph represents the average STAM-1 binding±S.E.M. normalized to the level of HA-arrestin-2 in the immunoprecipitates. STAM-1 binding to arrestin-2 was significantly increased upon agonist treatment as compared to vehicle. Data were analyzed by one-way ANOVA followed by a Bonferroni's post hoc test (*p<0.05). In FIG. 2B , STAM-1 is preferentially ubiquitinated upon CXCR4 activation. HEK293 cells co-transfected with HA-CXCR4, FLAG-STAM-1 or FLAG-STAM-2 and HA-ubiquitin were treated with 100 nM CXCL12 for 30 min. FLAG-STAM-1/2 were immunoprecipitated using an anti-FLAG antibody, followed by SDS-PAGE and immunoblotting to detect incorporated HA-ubiquitin. Blots were stripped and reprobed for FLAG-STAM-1/2 to assess loading. Cell lysates were analyzed for the presence of HA-CXCR4.
FIG. 3 contains representative micrographs from three independent experiments (bars=20 μm), and illustrates the co-localization of Arrestin-2, STAM-1 and CXCR4 on early endosomes. In FIG. 3A , serum-starved HEK293 cells expressing HA-CXCR4-YFP were treated with 30 nM CXCL12 or vehicle for about 30 minutes. Cells were fixed, permeabilized and double stained with anti-STAM-1 (red) and anti-EEAI (blue). White puncta in the merged images represents co-localization between all three proteins. The percent co-localization between CXCR4-YFP and STAM-1 was quantified as described below. The bar graph represents the percent co-localization between CXCR4-YFP and STAM-1 in vehicle and SDF treated cells±S.E.M. from 10 cells. Data were analyzed by Student t-test *p<0.0001. In FIGS. 3B , C and D, serum-starved HeLa cells were treated with about 30 nM CXCL12 or vehicle for about 30 minutes Cells were fixed, permeabilized and triple stained with anti-STAM-1 (green), anti-EEA1 (blue) and anti-CXCR4 (red) ( FIG. 3B ), triple stained with anti CXCR4 (red), anti-arrestin-2/3 (green) and anti-EEA1 (blue) ( FIG. 3C ); and HeLa cells expressing YFP-STAM-1 were double stained with arrestin-2/3 (red) and EEA1 (blue) ( FIG. 3D ). White puncta in the merged images represent co-localization between all three proteins. Co-localization between CXCR4 and STAM-1 ( FIG. 3B ; 20%), CXCR4 and arrestin ( FIG. 3C ; 30.7%), and YFP-STAM-1 and arrestin-2 ( FIG. 3D ; 26%). were quantified as described below. Inset represents 4-8× the size of the boxed region. DIC (differential interference contrast) images are shown.
FIG. 4 show data represent the mean±S.E.M. from three independent experiments, and illustrates that STAM-1 negatively regulates CXCR4 degradation. HEK293 cells stably expressing HA-CXCR4 were transfected with control (GAPD) and STAM-1 siRNA as described below. Cells were treated with vehicle (PBS containing about 0.01% BSA) or about 30 nM CXCL12 for about three hours and receptor levels were determined by immunoblotting followed by densitometric analysis. The bar graph represents the average amount of CXCR4 degraded±S.E.M. from three independent experiments (*p<0.05, unpaired t-test). In FIG. 4B , CXCR4 recycling was measured in HEK293 cells transfected with FLAG-CXCR4 and siRNA as described for FIG. 4A . Surface receptors were labeled with the M1 anti-FLAG antibody followed by treatment with about 30 nM of CXCL12 for about forty-five minutes in DMEM containing about 0.1% BSA, about 20 mM HEPES (pH 7.4) and about 1 mM Ca2+. Antibody remaining on the cell surface was stripped by two rapid washes with Ca2+/Mg2+ free PBS containing about 0.04% EDTA. Cells were then incubated in DMEM containing about 1 mM Ca2+ and about 10 μM AMD3100 (CXCR4 antagonist) and incubated at about 37° C. for about thirty to about sixty minutes. The amount of antibody reappearing on the cell surface was quantified by ELISA as described below, and used as an indicator of receptor recycling. Bars represent the percentage of internalized receptor that recycled±S.E.M. from three independent experiments. In FIG. 4C , bars represent the percentage of cell surface receptors internalized in cells treated with CXCL12 as compared with vehicle treated cells. The error bars represent S.E.M. from three independent experiments. In FIG. 4D , HeLa cells were transfected with GAPD and AMSH siRNA and treated and analyzed as in A.
FIG. 5 contains representative blots from one of three independent experiments, and illustrates that the STAM-1 GAT domain is both necessary and sufficient for arrestin-2 binding. In FIG. 5A , STAM-1 truncation mutants are represented schematically. Binding to GST-arrestin-2 is represented by (+) and (−) on the right as assessed by data shown in FIG. 11 . In FIG. 5B , equimolar amounts (about 600 nM) of GST-arrestin-2 and GST were incubated with lysates from HEK293 cells transiently transfected with FLAG-tagged full-length-STAM-1 or STAM-1-ΔGAT. In FIG. 5C , equimolar amounts (about 117 nM) of GST-STAM-1-GAT and GST were incubated with lysates from HEK293 cells transiently transfected with FLAG-tagged arrestin-2. In FIGS. 5B and 5C , bound proteins were detected by immunoblotting, followed by staining blots with Ponceau-S to assess the amount of GST fusion protein used in the binding assay.
FIG. 6 illustrates that the expression of the GAT domain disrupts the arrestin-2/STAM-1 interaction and accelerates CXCR4 degradation. In FIG. 6A , Lysates from HeLa cells co-transfected with HA-arrestin-2 and FLAG-STAM-1-GAT (SI-GAT) or empty vector (PCMV) were incubated with anti-HA and IgG control antibodies. Immunoprecipitates were analyzed by immunoblotting to detect bound endogenous STAM-1 and lysates were analyzed to assess expression of the various constructs. FIG. 6A contains representative blots from one of three independent experiments. In FIG. 6B , HA-CXCR4 degradation was assessed in HEK293 cells expressing FLAG-STAM-1-GAT or empty vector (pCMV) as described below. FIG. 6C graphically represents the percent of receptor degraded. Error bars represent S.E.M. from three independent experiments. Data were analyzed by two-way ANOVA and followed by a Bonferroni's post hoc test. (*p<0.0001).
FIG. 7 contains representative blots from one of three independent experiments, and illustrates mapping of the STAM-1 binding domain on arrestin-2. FIG. 7A schematically represents arrestin-2 truncation mutants used in the binding studies. Binding between GST-STAM-1 and HA-tagged arrestin-2 truncation mutants is shown as weak (+), intermediate (++) and strong (+++) on the right of the graph. In FIG. 7B , equimolar amounts (about 234 nM) of GST-arrestin-2, GST-Arr2-(25-161) and GST were incubated with lysates from HEK293 cells transiently transfected with FLAG-tagged STAM-1 and empty vector (PCMV-10). In FIG. 7C , equimolar amounts (about 276 nM) of GST-STAM-1, GST-STAM-1-GAT and GST alone were incubated with lysates from HEK293 cells transiently transfected with FLAG-Arr-2-(25-161). In FIG. 7C , bound proteins were detected by immunoblotting using an anti-FLAG antibody and blots were stained with Ponceau-S to assess the amount of GST-tagged protein used in the binding assay.
FIG. 8 illustrates that the expression of Arr2-(25-161) disrupts the STAM-1/arrestin-2 interaction and accelerates CXCR4 degradation. In FIG. 8A , lysates were prepared from HeLa cells co-transfected with T7-STAM-1, HA-arrestin-2 and increasing amounts (about 0.1 μg and about 2.5 μg) of FLAG-Arr2 (25-161). Lysates were divided into equal aliquots and incubated with either an anti-T7 polyclonal antibody or protein G agarose alone (control). Immunoprecipitates were analyzed by immunoblotting to detect bound HA-arrestin-2 and endogenous HRS and lysates were analyzed to assess the expression of the various constructs. FIG. 8A shows representative blots from one of three independent experiments. In FIG. 8B , HA-CXCR4 degradation was assessed in HEK293 cells expressing FLAG-Arr2-(25-161) or empty vector (PCMV) as described below. FIG. 8C is a graphical representation of percent receptor degraded. Error bars represent S.E.M. from three independent experiments. Data were analyzed by two-way ANOVA and followed by a Bonferroni's post hoc test. (*p<0.0001). Shown are representative blots from one of three independent experiments.
FIG. 9 illustrates that disrupting the STAM-1/arrestin-2 interaction inhibits HRS ubiquitination but does not effect on CXCR4 and STAM-1 ubiquitination. In FIGS. 9A and 9B , HEK293 cells stably expressing HA-CXCR4 were transfected with FLAG-ubiquitin and STAM-1-GAT domain or pCMV. In FIG. 9B , HeLa cells were transfected with HA-ubiquitin, T7-STAM-1 and STAM-1-GAT or pCMV. In FIG. 9C , cells were transfected as in FIG. 9A , except T7-HRS was also transfected. Cells were serum starved and treated with about 30 nM CXCL12 for about thirty to about sixty minutes, followed by immunoprecipitation and immunoblotting to detect incorporated ubiquitin as described below. Shown are representative blots from six ( FIG. 9A ) or three ( FIGS. 9B and 9C ) independent experiments.
FIG. 10 schematically represents a proposed mechanism for the role of the STAM-1/arrestin-2 complex in endosomal sorting of CXCR4. CXCR4 is ubiquitinated by the E3 ubiquitin ligase AIP4 at the plasma membrane, after which it is internalized onto early endosomes, although ubiquitination is not required for this process. Endosomes ubiquitinated CXCR4 is recognized by HRS, likely by an interaction involving the ubiquitin moiety (red) on CXCR4 and the UIM of HRS, and possibly via an interaction with arrestin-2. Arrestin-2 then interacts with STAM-1, which serves to recruit AIP4 culminating in the ubiquitination of HRS. It is speculated that this may trigger a conformational change in HRS induced by an interaction between the ubiquitin moiety (blue) and the internal UIM. CXCR4 is subsequently committed to downstream interactions with ESCRT-I-III, while arrestin-2, STAM-1, AIP4 and auto-inhibited HRS are recycled such that another round of sorting can take place.
FIGS. 11A through 11E represent equimolar amounts (about 134 nM) of GST-arrestin-2 and GST immobilized on glutathione-Sepharose resin were incubated with lysates from HEK293 cells transiently transfected with various FLAG-STAM-1 constructs. Bound proteins were detected by immunoblotting using the anti-FLAG M2 antibody, followed by staining with Ponceau-S ( FIGS. 11B-E ) or immunoblotting for GST ( FIG. 11A ) to assess the amount of GST fusion proteins used in the binding assays. Shown are representative blots from one of three independent experiments.
FIGS. 12A and 12B represent equimolar amounts (about 117 nM) of GST-STAM-1 and GST immobilized on glutathione-Sepharose resin were incubated with lysates from HEK293 cells transiently transfected with HA-arrestin-2 constructs. Bound proteins were detected by immunoblotting using the anti-HA antibody, followed by staining with Ponceau-S to assess the amount of GST fusion proteins used in the binding assay. Shown are representative blots from one of three independent experiments.
FIG. 13A represents data obtained when EGFR (epidermal growth factor receptor) degradation was assessed in HeLa cells transfected with FLAG-STAM-1-GAT, FLAG-Arr-2-(25-161) or pCMV. Cells were treated with about 100 ng/ml EFG for about one hour, followed by immunoblotting as described below. Shown are representative immunoblots from one of three independent experiments. FIG. 13B is a bar graph that represents the amount of EGFR degraded as compared to vehicle treated cells±S.E.M. from three independent experiments. Data were analyzed by one-way analysis of variance and were found not to be significantly different.
FIG. 14 contains a table identifying primers used for generating DNA constructs used in investigations leading to the present invention.
FIGS. 15 and 16 represent data obtained when cell migration was assessed by in vitro scratch assays and trans well assays, respectively.
DETAILED DESCRIPTION OF THE INVENTION
The chemokine receptor CXCR4, a G protein-coupled receptor, is targeted for lysosomal degradation via a ubiquitin-dependent mechanism that involves the endosomal sorting complex required for transport (ESCRT) machinery. The following reports an investigation which showed that arrestin-2 interacts with ESCRT-0, a protein complex that recognizes and sorts ubiquitinated cargo into the degradative pathway. In particular, STAM-1 (but, notably, not related STAM-2) interacts directly with arrestin-2 and co-localizes with CXCR4 on EEA1 positive early endosomes. Depletion of STAM-1 by RNAi and disruption of the arrestin-2/STAM-1 interaction accelerates agonist-promoted degradation of CXCR4, suggesting that STAM-1 via its interaction with arrestin-2 negatively regulates CXCR4 endosomal (lysosomal) sorting via ubiquitination of HRS. The investigation provided mechanistic insight into the role that arrestin-2 has on targeting CXCR4 into the degradative pathway and furthered an understanding of the complex molecular events that mediate endosomal sorting of GPCRs. Interestingly, disruption of the STAM-1/arrestin-2 interaction blocks agonist-promoted ubiquitination of HRS, but not CXCR4 and STAM-1 ubiquitination. Data from the investigation described below suggest a mechanism whereby arrestin-2, via its interaction with STAM-1, is able to modulate CXCR4 sorting by regulating the ubiquitination status of HRS.
Provided below are descriptions of materials and methods utilized in the investigation.
The following cell lines, antibodies and reagents were obtained and used in the investigation. HEK (Human embryonic kidney) 293 cells (obtained from Microbix of Toronto, Canada) and HeLa cells (American Type Culture Collection) were maintained in a Dulbecco's modified Eagles medium (DMEM; Hyclone) supplemented with 10% fetal bovine serum (FBS; HyClone Laboratories, Logan, Utah USA). HRS (M-79) rabbit polyclonal, the β-arrestin1/2 rabbit polyclonal (H-290) and mouse monoclonal (21-B1) antibodies were obtained from Santa Cruz Biotechnology (Santa Cruz, Calif. USA). Anti-GST monoclonal antibody and gluthathione Sepharose 4B resin were obtained from GE Healthcare (Buckinghamshire, UK). Anti-CXCR4 antibody previously described in Marchese and Benovic (2001). STAM-1 and AMSH polyclonal antibodies were obtained from ProteinTech Group (Chicago, Ill. USA). Arrestin-2 and anti-EEA1 monoclonal antibodies were obtained from BD Biosciences (San Jose, Calif. USA). Anti-HA polyclonal and monoclonal antibodies were obtained from Covance (Berkeley, Calif. USA). Anti-FLAG M2, M1, and M2-horse radish peroxidase conjugated monoclonal antibodies, FLAG polyclonal antibody, Alkaline Phosphatase conjugated anti-mouse antibody, and AMD3100 were obtained from Sigma (St. Louis, Mo. USA). An alkaline phosphatase substrate kit was obtained from Bio-Rad (Hercules, Calif. USA). Anti-T7 goat polyclonal antibody was obtained from Abcam (Cambridge, Mass. USA). Anti-epidermal growth factor receptor mouse monoclonal antibody was obtained from StressGen (Ann Arbor, Mich. USA). Anti-actin monoclonal antibody was obtained from MP Biomedicals (Aurora, Ohio USA). Stromal cell-derived factor-1α (CXCL12) and epidermal growth factor were obtained from PeproTech (Rockyhill, N.J. USA). Alexa-Fluor 635-conjugated goat anti-mouse, Alexa-Fluor 594-conjugated anti-rat, Alexa-Fluor 488-conjugated goat anti-rabbit and Alexa-Fluor 568-conjugated goat anti-rabbit antibodies were obtained from Molecular Probes (Eugene, Oreg. USA). The siRNA for GAPD, STAM-1 (GAACGAAGAUCCGAUGUAU) and AMSH (siGENOME SMARTpool D-012202) were obtained from Dharmacon RNA Technologies (Lafayette, Colo. USA).
The following DNA constructs obtained and used in the investigation were HA-CXCR4, FLAG-ubiquitin, HA-CXCR4-YFP, HA-arrestin-3 and HA-arrestin-2 constructs, as previously described in (Bhandari et al., 2007). Primers used for generating all constructs are listed in a table attached hereto as FIG. 14 . For STAM-1 truncation mutants (1-195, 1-269, 1-390, 391-540, 337-540, 270-540, 212-540, 144-540), full-length STAM-1 in 3xFLAG-pCMV-10 was amplified by PCR using primers flanking various regions of STAM-1 as indicated above and harboring 5′ and 3′ HindIII and XbaI restriction enzyme sites, respectively. PCR fragments were digested and ligated into the HindIII and XbaI sites of 3x-FLAG pCMV-10 (Sigma). For STAM-1-ΔGAT, the region encompassing amino acid residues 343-377 was deleted by two-step PCR with mutually annealing overlapping primers and flanking primers based on 3xFLAG-pCMV-10. Amplified product was digested and ligated into HindIII and XbaI sites of 3xFLAG-pCMV-10 and pGEX-4T2 (GE Healthcare). For STAM-1-GAT, amino acid residues 296-380 were amplified by PCR from full-length FLAG-STAM-1 and cloned into the HindIII and XbaI sites of 3xFLAG-pCMV-10 and EcoRI and XhoI sites of pGEX-4T2. For arrestin-2-(25-161) constructs, amino acid residues 25-161 were amplified by PCR from HA-arrestin-2-(1-161) and cloned into HindIII and XbaI sites of 3xFLAG pCMV-10 and SmaI and XhoI sites of pGEX-4T2, respectively. For YFP-STAM-1, full-length STAM-1 was amplified from FLAG-STAM-1 and cloned into the HindIII and KpnI sites of pEYFP-C1 vector (Clontech, Mountain View, Calif.). The sequence of all constructs was verified by sequencing.
The following GST-fusion protein binding assays were obtained and used in the investigation. Escherichia coli BL21 cells transformed with GST-fusion protein constructs or empty vector (pGEX-4T2) were grown overnight in Luria Broth (LB) containing about 100 μg/ml ampicillin. The following day, cultures were diluted (about 3.7%) and grown to an OD 600 of about 0.35 to about 0.40 at about 37° C., followed by induction with about 0.1 mM IPTG (isopropyl-1-thio-β- D -galactopyranoside) for about one hour at about 18° C. Cells were then pelleted by centrifugation and resuspended in about 1 mL binding buffer (about 20 mM Tris-Cl (pH 7.4), about 150 mM NaCl, about 0.1% Triton X-100, about 1 mM dithiothreitol, about 10 μg/ml leupeptin, about 10 μg/ml aprotinin, about 10 μg/ml pepstatin-A), followed by sonication and centrifugation. Clarified lysates were incubated with glutathione-Sepharose 4B resin for about one hour, washed and resuspended in binding buffer. Samples were analyzed by SDS-PAGE and stained with Gel-Code blue to estimate the protein amounts by comparing the samples to known amounts of purified bovine serum albumin (Roche, Fraction V). For binding assays, equimolar amounts of purified GST-fusion proteins were incubated with about 100 μl clarified cell lysate of HEK293 cells expressing the desired construct for about two to about four hours at about 4° C. For binding experiments using purified arrestin-2, GST fusion proteins were incubated with about 500 ng arrestin-2 in about 100 μl binding buffer for about one hour at about 4° C. Following incubation, samples were washed three times with binding buffer, eluted in 2× sample buffer by boiling for about 10 minutes, and bound proteins were detected by SDS-PAGE followed by immunoblotting.
The following degradation assay was obtained and used in the investigation. HEK293 cells stably expressing HA-CXCR4 or HeLa cells expressing endogenous levels of CXCR4 grown on 10-cm dishes were transfected with about 100 nM STAM-1, AMSH or GAPD siRNA using Lipofectamine 2000 transfection reagent (Invitrogen of Carlsbad, Calif. USA). To assess the role of STAM-1 and arrestin-2 minigene constructs on CXCR4 degradation, HEK293 cells grown on 10-cm dishes were co-transfected with about 1 μg HA-CXCR4 and about 9 μg FLAG-STAM-1-GAT, FLAG-arrestin-2-(25-161) or empty vector (pCMV-10) using TransIT-LTI transfection reagent (Mirus of Madison, Wis. USA). About twenty-four hours later, cells were passaged onto poly-L-lysine (about 0.1 mg/ml, Sigma) coated 24-well plates (HEK293 cells) or 6 well plates (HeLa cells) and grown for an additional eighteen to twenty-four hours. Cells were washed once and incubated with DMEM containing about 10% FBS and about 50 μg/ml cyclohexamide to stop protein synthesis for about fifteen minutes at about 37° C. Cells were then incubated with the same medium-containing vehicle (about 0.5% BSA) or about 30 nM CXCL12 for about one, two and three hours. Cells were washed and collected in about 300 μl 2× sample buffer, sonicated and receptor amounts were determined by SDS-PAGE followed by immunoblotting using an anti-HA monoclonal antibody or anti-CXCR4 antibody, as previously described (Marchese, A., Ubiquitination of chemokine receptors, Methods Enzymol, 460, 413-422 (2009). To assess EGFR degradation, HeLa cells grown on six well plates were transfected with about 3 μg FLAG-STAM-1-GAT, FLAG-arrestin-2-(25-161) or empty vector (pCMV-10) using TransIT-LT1 transfection reagent. Forty-eight hrs following transfection cells were incubated with DMEM containing 10% FBS and 50 μg/ml cyclohexamide to stop protein synthesis for 15 min at about 37° C. Cells were then incubated with the same medium containing vehicle (0.5% BSA) or 100 ng/ml EGF for 1 hr. Cells were processed as described above for CXCR4 degradation.
The following coimmunoprecipitation studies were used in the investigation. HeLa cells were transiently transfected with HA-Arrestin-2, HA-arrestin-3 or empty vector alone (pcDNA3) using TransIT-LT1 transfection reagent. About forty-eight hours later, cells were collected in an approximately 1.5 mL immunoprecipitation buffer (about 20 mM Na 2 PO 4 (pH 6.5), about 150 mM NaCl, about 1% (v/v) Triton-X 100, about 10 μg/ml leupeptin, about 10 μg/ml aprotinin, about 10 μg/ml pepstatin A) and incubated at about 4° C. for about thirty minutes. Cells were sonicated, centrifuged and clarified lysates were incubated with an anti-HA monoclonal antibody or isotype control antibody to immunoprecipitate HA-tagged arrestin-2/3 followed by immunoblotting to detect bound endogenous STAM-1 and HRS. Endogenous arrestins were immunoprecipitated from HeLa cells using an anti-arrestin2/3 mouse monoclonal or isotype control antibody followed by immunoblotting to detect bound endogenous STAM-1 and HRS. To assess the effect of the STAM-1-GAT minigene on the interaction between STAM-1 and arrestin-2, lysates from HeLa cells transfected with HA-arrestin-2 and FLAG-STAM-1-GAT or pCMV were incubated with an anti-HA or isotype control antibody and immunoprecipitates were analyzed for the presence of endogenous STAM-1. To assess the effect of the arrestin-2-(25-161) minigene on the interaction between STAM-1 and arrestin-2, HeLa cells transfected with T7-STAM-1, HA-arrestin-2 and FLAG-arrestin-2-(25-161) or pCMV were incubated with an anti-T7 polyclonal antibody and immunoprecipitates were analyzed for the presence of HA-arrestin-2 and endogenous HRS.
The following confocal Immunofluorescence microscopy techniques were used in the investigation. HEK293 cells transiently transfected with HA-CXCR4-YFP were passaged onto poly-L-lysine coated coverslips and allowed to grow for about twenty-four hours. HeLa cells were used to examine the distribution of endogenous CXCR4. Cells were washed once with warm DMEM containing about 20 mM HEPES (pH 7.5) and incubated in the same medium for about three to about four hours at about 37° C. Cells were treated with about 30 nM CXCL12 or vehicle for about thirty minutes, fixed with about 3.7% paraformaldehyde and then permeabilized with about 0.05% (w/v) saponin for about ten minutes, similar to a protocol previously described in Bhandari et al. (2007). Cells were co-incubated with STAM-1, EEA1 or arrestin2/3 antibodies. Endogenous CXCR4 in HeLa cells was stained with rat anti-CXCR4 monoclonal antibody. Briefly, after permeabilization and fixation, cells were incubated with about 1% BSA in about 0.05% saponin-PBS for about thirty minutes at about 37° C., followed by incubating with primary antibody for about one hour at about 37° C. Primary antibodies for STAM-1 and EEA1 were used at about 1:100 dilution and against CXCR4 and arrestin2/3 was used at an approximately 1:50 dilution. Cells were washed five times with 0.05% saponin-PBS, followed by incubating with appropriate Alexa-Fluor conjugated secondary antibodies for about thirty minutes at about 37° C. Finally cells were washed with PBS and fixed again with about 3.7% formaldehyde-PBS, and then mounted onto glass slides using mounting media containing DAPI. Samples were analyzed using a Zeiss LSM 510 laser scanning confocal microscope equipped with a Plan-Apo 63×/1.4 oil lens objective. Images were acquired using a 1.4 megapixel cooled extended spectra range RGB digital camera set at 512×512 resolution. Acquired images were analyzed using ImageJ software (version 1.41o) and the amount of co-localization between proteins was determined using the colocalization plug-in feature of MAG Biosystems Software (7.6.2.0).
The following ubiquitination assays were obtained and used in the investigation. For CXCR4 ubiquitination, HEK293 cells stably expressing HA-CXCR4 grown on 10-cm dishes were transfected with about 3 μg FLAG-ubiquitin. About eight hours later, cells were transfected either with about 10 μg FLAG-STAM-1-GAT, FLAG-Arr2-(25-161) or empty vector (pCMV). The next day, cells were passaged onto 6-cm dishes and allowed to grow for an additional twenty-four hours. The following day, cells were serum starved in DMEM containing about 20 mM HEPES for about three hours and then treated with about 30 nM SDF for about thirty minutes, washed once on ice with cold PBS and collected in an approximately 1 mL lysis buffer (about 50 mM Tris-Cl (pH 7.4), about 150 mM NaCl, about 5 mM EDTA, about 0.5% (w/v) sodium deoxycholate, about 1% (v/v) NP-40, about 0.1% (w/v) SDS, about 20 mM NEM, about 10 μg/ml each of leupeptin, aprotinin and pepstatin A). Samples were transferred into microcentrifuge tubes and placed at about 4° C. for about thirty minutes, sonicated, followed by centrifugation to pellet cellular debris. Clarified cell lysate was incubated with an anti-HA polyclonal antibody and the immunoprecipitates were analyzed by SDS-PAGE followed by immunoblotting using an anti-FLAG antibody conjugated to HRP.
To detect HRS ubiquitination, HEK293 cells stably expressing HA-CXCR4 were transfected with about 3 μg FLAG-ubiquitin. About eight hours later cells, were co-transfected with about 8 μg FLAG-STAM-1-GAT or empty vector (pCMV-10) and about 2 μg T7-tagged HRS. About twenty-four hours later, cells were passaged onto poly-L-lysine coated 6-cm dishes and the next day cells were serum starved for about four to about five hours in DMEM containing about 20 mM HEPES and were treated with about 30 nM SDF or vehicle alone for about thirty to about sixty minutes. Cells were washed with cold PBS and collected in an approximately 1 ml ubiquitination buffer (about 20 mM Tris-Cl (pH 7.5), about 150 mM NaCl, about 1% Triton-X 100, about 5 mM EDTA, about 20 mM NEM, about 10 μg/ml leupeptin, about 10 μg/ml aprotinin and about 10 μg/ml pepstatin-A), incubated for about thirty minutes at about 4° C., sonicated and clarified by centrifugation. HRS was immunoprecipitated using an anti-HRS polyclonal antibody and immunoprecipitates were analyzed by SDS-PAGE followed by immunoblotting to detect ubiquitinated HRS using an anti-FLAG antibody conjugated to HRP.
For STAM-1 ubiquitination experiments, HeLa cells grown in 6-well dishes were co-transfected with about 3 μg T7-STAM-1 and about 40 ng HA-ubiquitin. About eight hours later, cells were transfected with about 3 μg FLAG-STAM-1-GAT or empty vector (pCMV-10). About twenty-four hours later, cells were passed onto poly-L-lysine coated 6-cm dishes and the following day cells were serum starved, treated and processed as described above for HRS ubiquitination using a modified ubiquitination buffer (about 20 mM Na 2 PO 4 (pH 6.5), about 150 mM NaCl, about 1% Triton-X 100, about 20 mM NEM and protease inhibitor cocktail). Tagged STAM-1 was immunoprecipitated using an anti-T7 goat polyclonal antibody and immunoprecipitates were analyzed by SDS-PAGE followed by immunoblotting to detect ubiquitinated STAM-1 using an anti-HA monoclonal antibody.
The following internalization and recycling assays were obtained and used in the investigation. For measuring internalization and recycling of CXCR4, HEK293 cells grown on 10-cm dishes were co-transfected with FLAG-CXCR4 (about 1 μg) and about 100 nM STAM-1 or GAPD siRNA using Lipofectamine 2000 transfection reagent. The next day, cells were passaged onto poly-L-lysine coated 24-well plates and grown for an additional twenty-four hours. Cells were serum starved for about three to about four hours, placed on ice, washed once with DMEM containing about 0.1% BSA, about 20 mM HEPES and about 1 mM Ca2+ and then incubated in the same medium containing the calcium-dependent MI anti-FLAG antibody for about one hour on ice, which labels cell surface receptors only. Cells were washed and incubated in the same medium containing vehicle or about 30 nM CXCL12 for about forty-five minutes at about 37° C. To remove surface bound antibody, cells were washed three times with Ca2+ and Mg2+-free PBS containing about 0.04% EDTA. Cells were incubated in DMEM containing about 1 mM Ca2+ and the CXCR4 antagonist AMD3100 (about 10 μM) to block any further internalization for about thirty to about sixty minutes at about 37° C. The amount of receptor/antibody that recycled back to the cell surface was quantified by incubating cells with an alkaline-phosphatase conjugated goat anti-mouse IgG antibody. Briefly, cells were washed once with PBS containing about 1 mM Ca2+ and then fixed with about 3.7% paraformaldehyde for about five minutes on ice. Following fixation, cells were washed three times and incubated with alkaline phosphatase conjugated goat anti-mouse antibody diluted in PBS containing about 1% BSA for one hour at room temperature. Cells were then washed with PBS and incubated with p-nitrophenyl phosphate diluted in diethanolamine buffer (Bio-Rad) for about five to about fifteen minutes. Reactions were stopped by adding about 0.4 N NaOH and an aliquot was used to measure the absorbance at 405 nm. Percent receptor recycling was calculated by dividing the amount of receptor internalized by the amount of receptors recovered after incubation at different time intervals. To calculate the percent receptor internalization, the amount of receptor remaining on the cell surface was divided by the total number of receptors present on the cell surface before treatment with agonist.
Statistical analyses performed in the investigation used GraphPad Prism 4.00 for Macintosh (GraphPad Software, San Diego, Calif.; www.graphpad.com).
The following describes results that were obtained with the investigation. A first phase of the investigation established that arrestins interact with ESCRT-0. Although it has been previously shown that HRS and arrestin-2 mediate endosomal sorting of CXCR4 into the degradative pathway (Marchese et al., 2003; Bhandari et al., 2007), the molecular mechanisms have remained poorly understood. To gain mechanistic insight into this process, the investigation initially examined whether arrestin-2 interacts with ESCRT-0 by determining if it binds to HRS, STAM-1 or STAM-2. To address this, celilysates prepared from HEK293 cells expressing FLAG-tagged STAM-1, STAM-2 or HRS were incubated with bacterially purified GST-arrestin-2 and GST immobilized on glutathione-Sepharose resin. As shown in FIG. 1A , arrestin-2 bound to STAM-1 and HRS, but only weakly to STAM-2. To rule out the possibility of an intermediate protein mediating the interaction with STAM-1, similar experiments were performed using purified arrestin-2. As shown in FIG. 1B , GST-STAM-1, but not GST-STAM-2 or GST, bound to purified arrestin-2, which indicated that the interaction between arrestin-2 and STAM-1 is direct and confirming that arrestin-2 binds poorly to STAM-2. To determine whether arrestin-2 associates with ESCRT-0 in cells, HA-arrestin-2, HA-arrestin-3 or empty vector (pcDNA3) were transfected into HeLa cells followed by immunoprecipitation and immunoblotting to detect the presence of endogenous STAM-1 and HRS. Both STAM-1 and HRS were detected in the immunoprecipitates from cells expressing HA-arrestin-2, suggesting that arrestin-2 associates with HRS and STAM-1 in cells ( FIG. 1C ), while HRS, but not STAM-1, was detected in the HA-arrestin-3 immunoprecipitates ( FIG. 1C ). Similarly, endogenous arrestins also co-immunoprecipitated with endogenous STAM-1 and HRS in HeLa cells. Taken together, these data showed that the interaction between STAM-1 and non-visual arrestins is limited to arrestin-2, and that HRS interacts with both arrestin-2 and arrestin-3. Additionally, the data suggested that arrestin-2 exists in complex with a subpopulation of ESCRT-0 that includes STAM-1 and HRS, but not STAM-2.
The investigation then examined whether the interaction between arrestin and ESCRT-0 was regulated by activation of CXCR4. HeLa cells, which endogenously express CXCR4, were transfected with HA-arrestin-2 and treated with CXCL12 (about 30 nM) or vehicle (about 0.05% BSA-PBS) for various times, followed by immunoprecipitation of tagged arrestin-2 and immunoblotting to detect bound endogenous STAM-1. Activation of CXCR4 enhanced the interaction between STAM-1 and arrestin-2 as early as about thirty minutes after agonist treatment that persisted up to about sixty minutes ( FIG. 2A ). As STAM has been shown to be ubiquitinated (McCullough et al., 2004), the investigation next assessed whether CXCR4 activation promotes ubiquitination of STAM-1. HEK293 cells transfected with FLAG-tagged STAM-1 or STAM-2 and HA-tagged ubiquitin were treated with CXCL12 (about 100 nM) for about thirty minutes, followed by immunoprecipitation of tagged STAM proteins and immunoblotting to detect incorporation of tagged ubiquitin. As shown in FIG. 2B , STAM-1 was ubiquitinated by agonist activation of CXCR4, whereas STAM-2 was not ubiquitinated.
To confirm that arrestin-2 and STAM-1 are found within the same intracellular compartment, the investigation examined their distribution in cells by confocal immunofluorescence microscopy. As shown in FIG. 3A , in HEK293 cells transfected with YFP-tagged CXCR4 (a construct previously described in Bhandari et al., 2009), CXCR4 was mainly localized to the plasma membrane in vehicle-treated cells, whereas endogenous STAM-1 was mainly localized to punctate vesicles distributed throughout the cytoplasm, many of which also co-localized with EEA1, used here as a marker for early endosomes. In contrast, upon agonist treatment, CXCR4 distributed into an intracellular punctate pattern, indicating that it had internalized into vesicles that also contained STAM-1 and EEA1 ( FIG. 3A , bottom panels). The distribution of endogenous CXCR4 in HeLa cells treated with CXCL12 was also examined for about thirty minutes, revealing that CXCR4 co-localized with endogenous STAM-1 ( FIG. 3B ) and arrestin-2/3 ( FIG. 3C ) on EEA1 positive early endosomes. CXCR4 activation also promoted co-localization of arrestin-2/3 and YFP-tagged STAM-1 on early endosomes in HeLa cells ( FIG. 3D ). Taken together, the data suggested that, upon internalization, CXCR4 appears on early endosomes together with arrestin-2 and STAM-1.
As the data suggest that STAM-1 has a role in endosomal sorting of CXCR4, the investigation then examined agonist-promoted degradation of CXCR4 in cells that were depleted of STAM-1 by RNA interference. HEK293 cells stably expressing HA-CXCR4 were transfected with control or STAM-1 siRNA, followed by treatment with CXCL12 (about 30 nM) for about three hours and receptor degradation was assessed by immunoblot analysis, as previously described in Marchese et al. (2003). As shown in FIG. 4A , siRNA mediated depletion of STAM-1 led to a moderate, but statistically significant, increase in CXCR4 degradation, as compared to control siRNA treated cells, suggesting that STAM-1 negatively regulates agonist-promoted degradation of CXCR4. As the amount of receptor that is degraded is in part a function of the rate of receptor internalization and recycling, the effect of depleting STAM-1 on CXCR4 internalization and recycling was also examined. Cell surface FLAG-tagged CXCR4 was labeled with the M1 anti-FLAG antibody on ice in the presence of about 1 mM Ca2+, as the M1 antibody binds to the FLAG epitope in a calcium-dependent manner. Cells were washed to remove unbound antibody and the media was replaced with DMEM containing CXCL12 (about 30 nM) in the continued presence of about 1 mM Ca2+ and placed at about 37° C. for forty-five minutes to allow for internalization of the M1/CXCR4 complexes to take place. Antibody remaining on the surface, mostly representing un-internalized receptor, was removed by incubating cells with PBS containing EDTA (about 0.04%), a calcium-chelating agent. The amount of antibody (receptor) that recycled back to the cell surface was quantified by cell surface ELISA in parallel wells that were incubated at about 37° C. for about thirty to about sixty minutes. In control siRNA treated cells, approximately 20% of internalized CXCR4 recycled back to the cell surface after about thirty to about sixty minutes, similar to what was observed in STAM-1 depleted cells, suggesting that STAM-1 depletion had no effect on recycling of CXCR4 ( FIG. 4B ). In addition, agonist-promoted internalization of CXCR4 was similar in STAM-1 depleted cells, as compared to control siRNA treated cells, suggesting that STAM-1 is not involved in CXCR4 internalization ( FIG. 4C ).
The role of AMSH on agonist-promoted degradation of CXCR4 was also examined. AMSH is a deubiquitinating enzyme that interacts with STAM-1 and negatively regulates endosomal sorting of the epidermal growth factor receptor (EGFR) (see McCullough et al., (2004)). As shown in FIG. 4D , siRNA mediated depletion of AMSH did not affect agonist-promoted degradation of CXCR4 in HeLa cells, suggesting that AMSH does not regulate endosomal sorting of activated CXCR4. However, CXCR4 levels were elevated in vehicle-treated cells transfected with AMSH siRNA ( FIG. 4D ), suggesting that AMSH may regulate degradation of constitutively internalized CXCR4, similar to what has been recently reported in (Sierra, M. I., Wright, M. H., and Nash, P., AMSH interacts with ESCRT-0 to regulate the stability and trafficking of CXCR4, J. Biol. Chem., jbc.M109.061309, First Published on Feb. 16, 2010, doi: 10.1074/jbc.M109.061309 (2010). Taken together, the data suggested that STAM-1 negatively regulates CXCR4 degradation likely through a mechanism that directly attenuates endosomal sorting.
The investigation then turned to examining the arrestin-2 binding site on STAM-1. Arrestin-2 was recently reported to positively regulate CXCR4 sorting into the degradative pathway. To gain insight into the function of the arrestin-2/STAM-1 interaction on CXCR4 trafficking, the investigation initially set out to determine the mechanism of the interaction. To accomplish this, the investigation mapped the arrestin-2 binding region on STAM-1 by truncation mutagenesis. STAMs contain multiple domains, characterized by the presence of an amino-terminal VHS domain (Vps27, Hrs, STAM homology), UIM (ubiquitin interacting motif), SH3 (Src homology) domain, ITAM (immunoreceptor based tyrosine activation motif) and a GAT (GGA and TOM1 homologous) domain that partially overlaps with the ITAM (Prag, G., Watson, H., Kim, Y. C., Beach, B. M., Ghirlando, R., Hummer, G., Bonifacino, J. S., and Hurley, J. H., The Vps27/Hse1 complex is a GAT domain-based scaffold for ubiquitin-dependent sorting, Dev. Cell 12, 973-986 (2007); Ren, X., Koer, D. P., Kim, Y. C., Ghirlando, R., Saidi, L. F., Hummer, G., and Hurley, J. H., Hybrid structural model of the complete human ESCRT-0 complex, Structure 17, 406-416 (2009). Several STAM-1 N-terminal and C-terminal truncation mutants were created according to its domain organization, tagged with the FLAG epitope on the amino terminal end ( FIG. 5A ). GST-arrestin-2 and GST immobilized on glutatruone-Sepharose resin were incubated with lysates expressing the various STAM-1 truncation mutants and bound proteins were detected by immunoblotting. The results from these experiments are summarized in FIG. 5A and the data are shown in FIG. 11 . The arrestin-2 binding region was determined to reside between amino acid residues 296-380 on STAM-1. This region encompasses the GAT domain, which has been shown to form two tandem coiled-coil domains (amino-acid residues 301-377) (Prag et al., 2007; Ren et al., 2009). To further confirm that the GAT domain mediates binding to arrestin-2, deletion of the GAT domain completely abrogated STAM-1 binding to arrestin-2 ( FIG. 5B ) and the GAT domain alone fused to GST was able to bind to arrestin-2 ( FIG. 5C ).
To determine if the interaction between STAM-1 and arrestin-2 is important for CXCR4 trafficking, the investigation initially expressed the GAT domain as a minigene in cells and assessed whether it disrupted the arrestin-2/STAM-1 interaction. HeLa cells transfected with FLAG-SI-GAT and HA-arrestin-2 were subjected to immunoprecipitation using an anti-HA antibody followed by immunoblotting to detect the presence of endogenous STAM-1 in the immunoprecipitates. As shown in FIG. 6A , expression of the GAT domain disrupted the arrestin-2/STAM-1 interaction. To determine the function of the arrestin-2/STAM-1 interaction on lysosomal targeting of CXCR4, the investigation examined the effect of expressing the GAT domain on CXCR4 degradation. Remarkably, expression of the GAT domain significantly accelerated CXCR4 degradation following agonist treatment as compared to empty vector ( FIGS. 6B and 6C ). Taken together these data suggested that the STAM-1/arrestin-2 interaction negatively regulates CXCR4 sorting to lysosomes. As the STAM-1 GAT domain has been shown recently to bind to HRS and is predicted to be required for the assembly of ESCRT-0 (Ren et al., 2009), it is conceivable that arrestin-2 binding to STAM-1 displaces its interaction with HRS and promotes disassembly of ESCRT-0, which somehow negatively regulates the amount of CXCR4 that is targeted for lysosomal degradation.
To gain greater insight into this process, the investigation next set out to identify the STAM-1 binding region on arrestin-2 by truncation mutagenesis. Schematic representations of the arrestin-2 truncation mutants used are shown in FIG. 7A , generally as has been previously described (Bhandari et al., 2007). GST-STAM-1 and GST were incubated with lysates prepared from HEK293 cells expressing various HA-tagged arrestin-2 truncation mutants. The results from these binding experiments are summarized in FIG. 7A and the data are shown in FIG. 12 . Both the N- and C-terminal regions of arrestin-2 bound to GST-STAM1, but not GST, although binding to the N-terminal region appeared to be stronger, suggesting that it represented the main binding region. Further deletion of this region revealed that the STAM-1 binding site on arrestin-2 is between amino acid residues 1-161 ( FIG. 12B ). The investigation next determined if expression of this region as a minigene in cells also disrupted the arrestin-2/STAM-1 interaction. However, when expressed in cells the arrestin-2-(1-161) minigene completely blocked CXCR4 degradation (data not shown). N-terminal lysine residues within arrestin-2 are predicted to serve as phosphosensors and recognize phosphates attached to receptors (Kern, R. C., Kang, D. S., and Benovic, J. L., Arrestin2/clathrin interactionis regulated by key- and C-terminal regions in arrestin2, Biochemistry 48, 7190-7200 (2009), analogous to what has been observed for arrestin-1 (Vishnivetskiy, S. A., Schubert, C., Climaco, G. C., Gurevich, Y. V., Velez, M. G., and Gurevich, V. V. An additional phosphate-binding element in arrestin molecule, Implications for the mechanism of arrestin activation, J. Biol. Chem. 275, 41049-41057 (2000). Therefore the arrestin-2-(1-161) construct may bind to CXCR4 and have a dominant negative effect on CXCR4 internalization. To rule out any effects at the level of internalization, the first twenty-four amino acids from the N-terminus of arrestin-2 were deleted to create arrestin-2-(25-161) and the investigation initially tested the ability of this mutant to bind to STAM-1. As shown in FIG. 7B , GST fused to arrestin-2-(25-161), but not GST alone, efficiently bound to FLAG-STAM-1 expressed in cells. A FLAG-tagged construct of arrestin-2-(25-161) when expressed in HEK293 cells also bound to GST-STAM-1-GAT, suggesting that the STAM-1/GAT domain binding site on arrestin-2 is located between amino acid residues 25-161 ( FIG. 7C ).
The investigation next examined whether expression of arrestin-2-(25-161) disrupted the STAM-1/arrestin-2 interaction and modulated CXCR4 degradation. Expression of FLAG-arrestin-2-(25-161) markedly disrupted the interaction between arrestin-2 and STAM-1 ( FIG. 8A ) and significantly accelerated agonist-promoted degradation of CXCR4 ( FIGS. 8B and 8C ), similar to what was observed with the STAM-1 GAT domain ( FIG. 6 ). Taken together these data further indicated that the interaction between STAM-1 and arrestin-2 attenuates CXCR4 trafficking into the degradative pathway.
Finally, the investigation turned to examining role of the arrestin-2/STAM-1 interaction on the ubiquitination status of CXCR4, STAM-1 and HRS. STAM, through its interaction with several deubiquitinating enzymes, may regulate the ubiquitination status of both cargo and of itself (McCullough et al., 2006; Row et al., 2006). Therefore, one possibility is that the STAM-1/arrestin-2 interaction modulates the ubiquitination status of CXCR4 and STAM-1, thereby facilitating CXCR4 trafficking into the degradative pathway. To examine this possibility, the investigation examined the effect of expressing the GAT domain on the ubiquitination status of both CXCR4 and STAM-1. Surprisingly, expression of the GAT, as compared to empty vector, did not significantly change the ubiquitination status of CXCR4 ( FIG. 9A ) and STAM-1 ( FIG. 9B ), suggesting that the STAM-1/arrestin-2 interaction does not regulate their ubiquitination status. In sharp contrast, expression of the GAT domain blocked CXCR4 mediated ubiquitination of HRS ( FIG. 9C ). Therefore, taken together, the data showed that the STAM-1/arrestin-2 interaction is critical for modulating ubiquitination of HRS, which is likely important for regulating sorting of CXCR4 into the degradative pathway.
Non-visual arrestins are known for their ability to mediate GPCR desensitization, trafficking and signaling (Moore et al., 2007; Kovacs, J. J., Hara, M. R., Davenport, C. L., Kim, J., and Lefkowitz, R. J., Arrestin development: emerging roles for beta-arrestins ain developmental signaling pathways, Dev. Cell 17, 443-458 (2009). It has been reported that arrestin-2 interacts with AIP4 and mediates endosomal sorting of CXCR4 into the degradative pathway (Bhandari et al., 2007). The investigation reported above extended these findings to provide further mechanistic insight into this unprecedented role of arrestin-2. The data suggested that arrestin-2 mediates multiple interactions with ESCRT-0 on early endosomes, serving to regulate the amount of CXCR4 that is degraded. In view of the results of the investigation, it is believed that arrestin-2 likely links ubiquitinated CXCR4 to ESCRT-0 via an initial interaction with HRS and/or STAM-1. Interestingly, the data revealed that the arrestin-2 interaction with STAM-1 is important for regulating ubiquitination of HRS, which was believed to attenuate HRS sorting function, thereby controlling the extent to which CXCR4 is degraded. Such a mechanism is schematically depicted in FIG. 10 .
The investigation employed truncation mutagenesis to narrow the arrestin-2 binding region on STAM-1 to the GAT domain and the STAM-1 binding region on arrestin-2 to amino acid residues 25-161. Expression of both of these domains similarly disrupted the arrestin-2/STAM-1 interaction and enhanced against promoted degradation of CXCR4. The data obtained in the investigation were consistent with the notion that the STAM-1/arrestin-2 interaction negatively regulates sorting of CXCR4 into the degradative pathway. This interaction may be specific to modulating CXCR4 and/or GPCR sorting, as EGFR degradation was not altered by expression of the STAM-1 GAT domain and arrestin-2-(25-161) ( FIG. 13 ). Depletion of STAM-1 by siRNA also enhanced CXCR4 degradation, further revealing that STAM-1 negatively regulates CXCR4 endosomal sorting ( FIG. 4A ). In contrast, it had been previously shown that arrestin-2 promotes CXCR4 sorting (Bhandari et al., 2007) which, when considered with the data obtained in the investigation, indicates that arrestin-2 has opposing effects on CXCR4 degradation. This suggests that arrestin-2 likely acts at multiple steps in the sorting process and may initially act upstream of STAM-1 to positively regulate sorting of CXCR4 into the degradative pathway. Arrestin-2 interacts with the C-tail of CXCR4 (Busillo, J. M., Armando, S., Sengupta, R., Meucci, O., Bouvier, M., and Benovic, J. L., Site-specific phosphorylation of CXCR4 is dynamically regulated by multiple kinases and results in differential modulation of CXCR4 signaling, J. Biol. Chem., 285, 7805-7817 (2010), and therefore it is possible that arrestin-2 binds to CXCR4 on endosomes in order to recruit CXCR4 to ESCRT-0, possibly through an interaction with either HRS and/or STAM-1. This is consistent with the data from the investigation that showed that arrestin-2 co-localizes with CXCR4 and STAM-1 on early endosomes upon agonist activation ( FIG. 3 ). Interestingly, a recent study found that Rim8, a S. cerevisiae molecule distantly related to mammalian arrestins, may function to directly recruit a putative 7™ receptor to the ESCRT machinery (Herrador, A., Herranz, S., Lara, D., and Vincent, O., Recruitment of the ESCRT machinery to a putative seven transmembrane-domain receptor is mediated by an arrestin-related protein, Mol. Cell Biol. 30, 897-907 (2010). After arrestin-2 initially directs CXCR4 to ESCRT-0, this is likely followed by an interaction with STAM-1 to attenuate CXCR4 degradation. Therefore, the results from the investigation are consistent with a model in which arrestin-2 influences CXCR4 sorting positively and negatively, and it is a balance of these two activities that dictates the extent to which CXCR4 is degraded.
The investigation led to the question as to how STAM-1 mediates the negative action of arrestin-2 on CXCR4 degradation. As ubiquitination of HRS is markedly reduced by expression of the GAT domain, it is likely that STAM-1 via its interaction with arrestin-2 regulates the ubiquitination status of HRS to control CXCR4 degradation. This suggests that CXCR4 promoted ubiquitination of HRS ( FIG. 9C ; Marchese et al. (2003)) attenuates its sorting activity. HRS contains a UIM that is thought to bind to ubiquitin moieties on cargo to recruit them into the degradative pathway (Hirano, S., Kawasaki, M., Ura, H., Kato, R., Raiborg, C., Stenmark, H., and Wakatsuki, S., Double-sided ubiquitin binding of Hrs-UIM in endosomal protein sorting, Nat. Struct. Mol. Biol. 13, 272-277 (2006). Interestingly, monoubiquitination of UBD containing proteins is thought to induce an intramolecular interaction between the ubiquitin moiety and the internal UBD, which in a protein such as HRS may induce an auto-inhibitory conformation such that it can no longer bind to ubiquitin moieties on cargo (Hoeller, D., Crosetto, N., Blagoev, B., Raiborg, C., Tikkanen, R., Wagner, S., Kowanetz, K., Breitling, R., Mann, M., Stenmark, H., Dikic, I., Regulation of ubiquitin-binding proteins by monoubiquitination, Nat. Cell Biol. 8, 163-169 (2006). As HRS ubiquitination is reduced by expression of the GAT domain, a loss of auto-inhibition likely enhances its sorting function culminating in enhanced degradation of CXCR4. Therefore, CXCR4 promoted ubiquitination of HRS may occur once HRS has completed its sorting function and CXCR4 has been committed to downstream elements of the degradative pathway ( FIG. 10 ).
The investigation also raised the question as to how arrestin-2/STAM-1 regulates the ubiquitination status of HRS. It was previously shown that arrestin-2 interacts with AIP4 to regulate endosomal sorting of CXCR4 (Bhandari et al., 2007) and that AIP4 mediates agonist-promoted ubiquitination of HRS (Marchese et al., 2003). Therefore it is possible that arrestin-2, together with STAM-1, may serve to bridge AIP4 and HRS in order to facilitate HRS ubiquitination by AIP4. This is consistent with the investigation's data that showed that expression of arrestin-2-(25-161) also displaces HRS binding to arrestin-2/STAM-1 ( FIG. 8A ). Alternatively, the arrestin-2/STAM-1 complex may regulate HRS deubiquitination. STAM has been shown to interact with deubiquitinating enzymes, such as AMSH and UBPY, which have been shown to regulate the ubiquitination status of cargo (for example, EGFR, protease activated receptor 2) and/or of STAM itself (McCullough et al., 2004; Row et al., 2006; Hasdemir, B., Murphy, J. E., Cottrell, G. S., and Bunnett, N. W., Endosomal deubiquitinating enzymes control ubiquitination and down-regulation of protease-activated receptor 2, J. Biol. Chem. 284, 28453-28466 (2009). However, from the investigation, the arrestin-2/STAM-1 complex does not appear to modulate the ubiquitination status of CXCR4 or STAM-1 ( FIG. 9 ). In addition, depletion of AMSH did not affect agonist-promoted degradation of CXCR4 ( FIG. 4D ), suggesting that it may not be linked to this process, although it does not exclude the possibility that other DUBs may be involved (Row et al., 2006; Shenoy, S. K., Modi, A. S., Shukla, A. K., Xiao, K., Berthouze, M., Ahn, S., Wilkinson, K. D., Miller, W. E., and Lefkowitz, R. J., Beta-arrestin-dependent signaling and trafficking of 7-transmembrane receptors is reciprocally regulated by the deubiquitinase USP33 and the E3 ligase Mdm2. Proc. Nat. Acad. Sci. USA 106, 6650-6655 (2009). Nevertheless, the results of the investigation were consistent with the notion that the arrestin-2/STAM-1 complex mediates ubiquitination of HRS likely via AIP4.
Interestingly, the investigation appeared to indicate that STAM-2 is excluded from endosomal sorting of CXCR4, since arrestin-2 binds selectively to STAM-1 ( FIG. 1A ). This suggests that CXCR4 sorting is restricted to ESCRT-0 complexes that contain STAM-1 but not STAM-2. It was also observed through the investigation that activation of CXCR4 selectively enhances STAM-1 ubiquitination over STAM-2 ( FIG. 2B ), further supporting the selectivity of STAM-1 towards CXCR4. However, the arrestin-2/STAM-1 interaction may not be linked to STAM-1 ubiquitination ( FIG. 9B ). Presently, the function of STAM-1 ubiquitination on CXCR4 trafficking remains unknown, although it is possible that it may have a role in some other aspect of CXCR4 related functions. Though polyubiquitination of STAM has been linked to its degradation (Row et al., 2006), it is doubtful that CXCR4 regulates STAM-1 stability as no differences were observed in STAM-1 levels in cells treated with CXCL12 (data not shown).
In another series of investigations, further work was conducted with the minigenes STAM-1(296-380) (referred to as STAM-1-GAT-domain above) and Arr2(25-161) whereby it was shown that when expressed in cells they attenuate cell migration induced by SDF-1α activation of CXCR4. Cell migration was monitored using two distinct commonly in vitro assays: a scratch assay ( FIG. 15 ) and a trans well assay ( FIG. 16 ). The results of both showed that STAM-1(296-380) and Arr2(25-161) expression in cells attenuates CXCR4-mediated cell migration. The data obtained with this investigation provided significant mechanistic insight into the molecular pathways that mediate CXCR4-induced cell migration and establish the STAM-1/arrestin-2 complex as a potential therapeutic target to treat cancer metastasis.
On the basis of the above, it can be appreciated that the investigation provided a mechanistic insight into the role of arrestin-2 in endosomal sorting of CXCR4 via multiple interactions with ESCRT-0. The investigation revealed that, via an interaction with STAM-1, arrestin-2 serves as an adaptor to regulate endosomal ubiquitination events that are critical for regulating the sorting of ubiquitinated CXCR4 into the degradative pathway, thereby controlling the amount of CXCR4 that is degraded. On this basis, it was concluded that an interaction between the adaptor proteins arrestin-2 and STAM-1 enables the arrestin-2/STAM-1 complex to be used as a therapeutic target to modulate CXCR4 levels and to modulate CXCL12-evoked cell migration. This aspect of the invention can be extended to the use of the arrestin-2/STAM-1 complex to identify and develop novel pharmacological agents capable of targeting the arrestin-2/STAM-1 interaction for therapeutic intervention, for example, to treat metastasis in cancer patients, and in particular patients with cancers that exhibit elevated levels of CXCR4 in the tumor cells.
Though the invention has been described in terms of observations and results obtained during an investigation in which a particular series of procedures was performed, the scope of the invention is to be limited only by the following claims.
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Methods of utilizing the arrestin-2/sTAM-1 complex as a therapeutic target. The methods include treating cells of a living organism to mediate an interaction between arrestin-2 and STAM-1 adapter protein molecules, wherein the interaction is characterized by the arrestin-2 adapter protein molecule directly binding to the STAM-2 adapter protein molecule. Pharmacological agents can be identified for therapeutic uses by determining whether the pharmacological agent disrupts the interaction between the arrestin-2 and STAM-1 adapter protein molecules.
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CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 60/785,659, filed Mar. 23, 2006, the disclosure of which is hereby incorporated by reference herein.
FIELD OF THE INVENTION
[0002] This invention relates to devices for building shelters to span between walls or to rest directly on the ground, and for bridging obstacles to enable pedestrians and vehicles to traverse the obstacles. More particularly, this invention relates to a portable structure, or bridge, comprising a plurality of elements connected to one another by a tension device.
BACKGROUND OF THE INVENTION
[0003] This invention was intended to fulfill the need for easily transportable structures, simple in design, and able to be quickly erected as a bridge and/or shelter. Such shelter or bridge would satisfy the demand for emergency and rescue operations where instant bridges or shelters are necessary. The army requires light mobile bridges that can be speedily erected and light structures to facilitate storage and shelter for soldiers and equipment.
[0004] Existing military mobile bridge solutions are bulky, costly and heavy to transport. For example, the Armored Vehicle Launcher (AVLB), the XM104 Wolverine and the Leguan Bridge are not lightweight structures that are simple to construct and transport. Previously available lightweight mobile bridge structures are not designed or capable of carrying heavy loads like cars, tanks and trailers.
[0005] Consequently, a need exists for an improved mobile bridge or shelter structure which is simple to construct, mobile, lightweight and inexpensive to manufacture.
SUMMARY OF THE INVENTION
[0006] The present invention is directed to a lightweight shelter, roof or bridge structure which is mobile and easily erected. The structure is made of a plurality of elements which could be poles or tubes having a cross-sectional shape of a square, U-shaped, triangle, rectangle, trapezoids, circle, I-beam or any combination thereof. The elements are produced from plastic, polymers, wood or metal. The elements are laid together and the lower surfaces of the elements are connected by a tension device which could be cables, mesh or straps. The entire structure can be folded or rolled into a cylindrical shape for mobility.
[0007] The structure of the present invention is a low cost, self-contained unit which may be carried on a truck bed, trailer, tractor, tank or ship and transported very easily to any desired location. The device is designed in such a way that the bridge elements can move relative to one another, and, for example, could be rolled upon itself or around a reel for transport. Accordingly, the device does not occupy a large space. The bridge structure or shelter can be designed for use by pedestrians, civilian or military vehicles, including tractors and tanks. An advantage of the present invention is that it can be erected in a very short time as once the structure is unrolled and supported at both of its ends, it is ready for service. Another advantage of the present invention is that the device is a self-contained unit, and once it is erected it can be operated without an outside power source, and requires little or no maintenance. The bridge structure can be extended to any desired length in proportion to the size of its individual elements and tension device. The device does not require a large crew to transport or operate and can be used on land or span over water. The device is portable and has an excellent strength-to-weight ratio and can be quickly deployed without the use of any additional supports.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The invention is described in more detail herein with reference to the accompanying drawings, wherein like reference characters refer to the same parts throughout the several views and in which:
[0009] FIG. 1 is a perspective view of one embodiment of the present invention;
[0010] FIG. 2 is a schematic view of the geometry of individual bridge elements;
[0011] FIG. 3 is a bottom view of the bridge structure of the present invention illustrating a first tension device;
[0012] FIG. 4A is a bottom perspective view of a second embodiment of the present invention;
[0013] FIG. 4B is a cross-sectional side view of the embodiment of FIG. 4A with an alternative tension device;
[0014] FIG. 5 is a bottom view of a third embodiment of the present invention;
[0015] FIG. 6 is a side view of the embodiment of FIG. 1 ;
[0016] FIG. 7 is a side view illustrating one method of retracting the bridge device of the present invention and storing the bridge on a reel;
[0017] FIG. 8 is a schematic view of a first method of deploying the bridge device of the present invention;
[0018] FIG. 9 is a schematic view of a second method of deploying the bridge device of the present invention; and
[0019] FIG. 10 is a perspective view of the present invention as a shelter.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Referring to FIG. 1 , a mobile compression and tension bridge 10 of the present invention is illustrated. The bridge 10 comprises a plurality of bridge elements 12 which are connected to one another by a tension member, which is discussed in more detail subsequently herein. The bridge elements 12 are connected in a side-by-side fashion and they are adapted to form an arch when they are extended outwardly from base members 14 . As can be seen in FIG. 1 , the cross-sectional configuration of the individual bridge elements is square, however as can be shown in FIG. 2 , the bridge elements 12 can have a variety of cross-sectional geometric configurations such as U-shaped 12 a, square 12 b, rectangular 12 c, trapezoidal 12 d, triangular 12 e, circular 12 f or I-beam 12 g. It is to be understood that these geometrical configurations are by way of example and are not to be so limited since other geometric configurations may also be suitable for a particular application.
[0021] As shown in FIGS. 3 and 4 , the individual bridge elements are attached to each other and held by a tension device 16 located on a bottom surface of the bridge elements. Preferably more than one tension device 16 are positioned along the lower surface of the bridge elements. FIG. 3 illustrates four metal strips spaced along the lower surface of the bridge elements and FIG. 4 illustrates two metal strips spaced apart along the lower surface the bridge elements. It is to be understood that any number of tension members can be located along the lower surface of the bridge element depending upon the width of the structure for the overall application.
[0022] As seen best in FIGS. 4A and 4B , the tension members are attached to each bridge element 12 by a fastener 18 which extends through the tension member and into the bridge element. By way of example, for bridge elements which are U-shaped, the fastener would extend through the tension member and through the upper surface of the bridge element. For a square bridge element, the fastener would extend through the tension member and the bottom surface and/or the top surface of the bridge element. The tension member connected along the bottom surface of the bridge element device allows the bridge elements to be flexible and rolled for transport or storage. The tension of FIG. 4A is a metal strap 16 and the tension device of FIG. 4B is a cable 19 . Fastener 18 is a screw which is held in place by a nut 21 .
[0023] FIG. 5 illustrates an alternative tension member which is a cable 20 . Cable 20 is attached to each individual bridge element 12 by a fastener 22 . Yet another tension member for connecting the individual bridge elements is a mesh 24 as shown in FIG. 7 .
[0024] The mobile compression and tension bridge 10 of the present invention provides its own rigidity and stability for an extended bridge structure as weight is placed upon the bridge. As the bridge is loaded, the top part of the bridge elements will absorb compression forces and the tension members at the bottom of the bridge elements will absorb the tension forces. As the bridge carries a heavier load, the arch shape will become flatter and the tension members will bear more and more of the load. As the arch becomes more flat, the supporting ends of the bridge will move outward. When the load is removed from the bridge, the bridge may resume its original arch form and the supporting end components will move inward. Optionally, beams can be placed on the top surface of the bridge compressed from one end to another when the bridge is fully loaded to maintain the structure permanently in a compressed position. Further optional components can be used with the bridge structure such as railing, which could be an L-shaped post positioned in the opening at the end of the bridge element, securing it with bolts and connecting the tops of these posts by a rope or a cable to create a railing. These railings could be connected to each other with diagonal cables and create another method to sustain the bridge permanently in one position.
[0025] In order for the bridge elements to form an arcuate contour in an extended position, the bottom of each individual bridge element could have a width shorter than the top portion of each element, i.e. trapezoidal, or narrow inserts 26 as shown in FIG. 6 could be placed between the individual bridge elements towards the top of the elements to form the arch. Generally speaking, the length of each element is in the range of about three to fifty feet long, and the width ranging between three inches to ten feet.
[0026] Because of the ability to be flexible, the bridge structure can be rolled onto a reel 28 as shown if FIG. 7 . Once rolled onto a reel, the bridge structure occupies less space as it is coiled onto the reel and becomes transportable. The distance which an extended bridge structure is capable of spanning is dependent upon the size of the individual elements. Generally speaking, the bridge is adapted to span distances of about ten to two-hundred feet, or more. Preferably, the bridge elements are made of wood, plastic, metal or carbon fiber material where strength and lightweight are required. The fasteners used to attach the tension member to the bridge elements could be screws, bolts, rivets, clamps, hooks or other bonding methods, such as welding or glue.
[0027] The transport reel 28 is preferably circular and constructed of metal, plastic or composite fiber. The reel may be driven by a motor or include a crank to be manually actuated. The entire device may be mounted on a trailer to be towed or positioned on a truck bed 30 as shown in FIG. 7 .
[0028] As shown if FIG. 8 , to span a body of water 32 an end 34 of the bridge can be placed on a pontoon 36 and floated across the water to bank 38 . The opposite end of the bridge would then be positioned on bank 40 . Referring to FIG. 9 the bridge could be deployed over a ravine 42 by having telescoping rails 44 extending from truck 46 and the bridge unwound and slid across the rails until reaching land. To bridge over water, a bridge made of sealed tubes could be unrolled and floated over the water in any orientation. Once reaching the opposite bank, it could be positioned accordingly. In a configuration where the bridge is floating, it could be pulled from one location on the water to another. This could have useful application in flooded areas. If one or more of the individual bridge elements are damaged, they could be replaced on site.
[0029] FIG. 10 illustrates the invention utilized as a shelter structure 50 . In this embodiment, the individual elements 52 are held in a much more significant arch by larger inserts between the elements. The arch has a sufficient height that it can accommodate occupants or equipment below the arch or be placed between walls.
[0030] While the present invention has been shown and described in terms of multiple embodiments thereof, it will be understood that this invention is not to be limited and that changes and modifications can be made without departing from the scope of the invention as hereinafter claimed.
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A mobile compression and tension bridge and shelter structure having a plurality of individual structural elements that are parallel to each other and perpendicular to the length of the bridge or shelter and are flexibly connected to one another on a bottom surface forming an arch caused by the shape of the elements or by placing spacers between the elements with at least one tension device attached to each structural element.
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The present invention relates to wood pulp processing and specifically to an apparatus and method for the digester of a pulp mill. More specifically, the present invention relates to such a method and apparatus which permits greater flexibility in the composition of the liquor used in the digester by providing a system for the removal of scaling that would otherwise form on the strainers of the digester when certain compositions of the liquor are used with certain types of wood chips.
BACKGROUND OF THE INVENTION
In the pulp processing industry, wood chips are introduced into a digester where these are treated under high pressure and temperature by a liquor that is introduced into the digester to break down the lignin and sugar content of the wood fibers, leaving only the cellulose. During the digesting process, the liquor is drawn out of the digester at various locations and recirculated to other locations in the digester. So that the wood chips remain in the digester, it is necessary that the liquor that is being removed passes through a strainer which has slot like openings that prevent the passing of wood chips but permit the passage of the liquor therethrough.
If the screens in the digester become clogged, then it is commonly necessary to shut down the digester and remove the scaling from the strainers. Such a shutdown can be extremely costly, and make it economically unfeasible to operate the pulp mill in that manner. Quite commonly this problem is alleviated by formulating the composition of the liquor so that certain components of the liquor will prevent the formation of the scaling on the strainers.
This formulation will depend to some extent on the species of the wood from which the chips are made. For example, if the wood has a high percentage of pitch, the scaling would quite possibly be more of a problem. An example of this is in a digester which uses alcohol (either ethyl or methyl alcohol) as one of the major components of the liquor. If soft wood is being treated in the digester, there is more of a tendency for scaling to form. However, the addition of sodium hydroxide to the liquor composition substantially alleviates the scaling problem.
The further treatment of the black liquor resulting from the digester process is also an important part of the operation of a pulp mill. In order to operate a pulp mill economically, it is generally necessary to process or utilize the black liquor in some manner to extract value therefrom. This can be done in various ways. Generally, the black liquor goes to an evaporator where a substantial portion of the water content is removed. Then the residue from the black liquor can be burned to generate heat energy which is utilized in other parts of the pulp mill and to recover the non-organic chemicals in the liquor for recirculation in the pulping process. Alternatively, the residue remaining after the evaporation of the black liquor can be utilized in other applications, such as producing adhesive for particle board or animal food pelletizing.
SUMMARY OF THE INVENTION
In view of the foregoing, it is the principle object of the present invention to provide method and apparatus for a digester in a pulp processing system which is able to alleviate the problem of the formation of scaling on the strainers of the digesters to allow more flexibility in the formulation of the composition of the digesting liquor. One specific advantage of the present invention can in some instances result in enabling the black liquor to be utilized in a manner which could be more profitable.
A specific application of the present invention is to be utilized in a digester using ethyl or methyl alcohol as the main active ingredient of the digesting liquor, while processing wood chips (such as wood chips from soft woods) which are prone to cause clogging of the strainers.
The pulp digester comprises a containing structure defining a digesting chamber. There is inlet means to introduce wood chips and digesting liquor into the digesting chamber.
There is at least one liquor extraction means at an extraction region of the digester. The liquor extraction means comprises a strainer means positioned in the digester to receive an outflow of liquor through said strainer means and prevent entry of wood chip products through said strainer means. There is also a collector means to receive the liquor that passes from the digester through the strainer.
There is solvent means to selectively direct a solvent under pressure in a counterflow direction to pass through said strainer means in a direction opposite to flow of liquor through said strainer means while said liquor and said wood chips are in said digester under pressure. Thus, the digester is able to continue operation, while solvent can selectively and periodically be passed through said strainer means to remove accumulation of scaling on said strainer means.
In a preferred form, the digester comprises means to withdraw solvent from said collector means to recirculating tank means and to recirculate solvent back to said solvent means for subsequent use.
Also in the preferred form, there is means to direct pressurized steam to evacuate the collector means at least partially of liquor, and means to selectively direct the solvent under steam pressure to and through the strainer means.
In the method of the present invention, a digester is provided as noted above. Solvent under pressure is selectively directed in a counterflow direction to pass through the strainer means, as described above.
Other features will become apparent from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a somewhat schematic drawing illustrating a digesting portion of a prior art pulp processing system in which the present invention can be effectively utilized;
FIG. 2 is a semi-schematic view showing a pulp digester, such as that shown in FIG. 1, incorporating the teaching of the present invention in a pulp processing system similar to that shown in FIG. 1;
FIG. 3 is an elevational view looking toward the interior face of a portion of a strainer utilized in the present invention;
FIG. 4 is a sectional view taken along lines 4--4 of FIG. 3;
DESCRIPTION OF THE PREFERRED EMBODIMENT
It is believed that a clearer understanding of the present invention will be obtained by first reviewing the digesting portion of a typical pulp mill for which the present invention is particularly adapted. With reference to FIG. 1, the wood chips are first subjected to magnetic separation of tramp iron and screening at location 1, and then directed into a surge bin of a hopper indicated at 2. From the hopper, the chips flow into a chip meter 3 which controls the rate of flow of the chips which then pass into a low pressure feeder 4.
The feeder 4 directs the chips into a steaming vessel 5 that is kept at between 15 to 20 PSI where the chips are pre-steamed. The chips are then directed from the steaming vessel 5 into the chip chute 6, from which the chips move to a high pressure feeder 7. The chips are flushed into the feeder by means of a chip chute circulating pump 8. As seen in FIG. 1, the flow from the pump 8 into the chip chute 6 and to the feeder 7 is in a counterclockwise direction. Make up liquor for the chip chute 6 is derived from the level tank 9. The wood chips mixed with a certain amount of liquor are then moved from the feeder 7 through a line 11 into a top strainer 12 to the top of the digester 14. A high pressure pump 10 introduces the cooking liquor to the digester, as well as the excess liquor from the chip chute. The volume of the cooking liquor can be controlled by a magnetic flow meter.
In general, the digester pressure is controlled so as to be at about 165 PSI. The chips and the cooking liquor gradually move downwardly in the digester, first passing into an upper impregnation zone I and then to the heating zone II.
The temperature is raised in two steps by two cooking circulating systems, which comprise extraction strainers, pumps and central circulating chambers. Three heaters 13 are shown. After heating, the chips and liquor pass downwardly through the cooking zone III of the digester. As the chips then pass into the lower washing zone IV of the digester, extracted wash liquor is circulated through the chips to provide a quench of the cooking reaction. The chips continue to pass downwardly in the washing zone IV, then to be discharged. The entire sequence is arranged so that the duration of the digesting process is about one and one half to four hours.
Wash liquor from a subsequent filter tank or fresh hot water is pumped into the bottom of the digester and flows upwardly countercurrently to the chip flow. Elevated temperatures of 125° to 135° C. are controlled in the diffusion zone by an auxiliary wash liquor circulation and heater system.
At various locations in the digester, the liquor is recirculated to an upper location. A portion of the liquor that is extracted between zone III and zone IV is directed to a flash tank 17, and thence to flash heat evaporators. The pulp that is extracted from the bottom of the digester is directed to a blow unit 16 which has a pressure reducing function, and then further directed to a brown stock washer or to some other location for further processing. Eventually the black liquor developed during the digesting process is directed to an evaporator 19, for further processing as indicated schematically at 20.
Since the section of the wood pulp processing system shown in FIG. 1 (and also the entire pulp processing operation which would be compatible with the digesting section shown in FIG. 1) are well known in the prior art, these will not be described in detail any further. It is to be understood that to the extent that the novel components of the present invention cooperate advantageously with the other components or sections with the entire pulp processing operation, such components are deemed to be part of the disclosure of the present invention. For example, the present invention can result in an advantageous further use of the components derived from the black liquor, and as will be disclosed more fully later herein, this may permit the black liquor to be used in the manner that the lignin and other components derived from the wood fiber can advantageously be used for example, as a glue, binder, or constituent of other products such as panels, animal feed, etc.
FIG. 2 shows the digester system 100 of the present invention, comprising a digester 102 which is, or may be, similar in overall construction of the prior art digester as shown at 14 in FIG. 1. This digester 102 comprises a vertically aligned containing structure 104, also called a tower, having an upper end 106 into which wood pulp is directed through an intake opening schematically shown at 108, and into which processing liquor is introduced at 110 (also shown schematically). A pulp outlet is shown schematically at 111. As shown herein, the digester has an upper section 112 of smaller diameter, an intermediate section 114 of a moderately increased diameter, and a lower section 116.
At the lower end of the upper section 112 there is a first liquor extraction area 118 where there is a cylindrically shaped strainer 120 through which the liquor passes to discharge passageways 122 and thence into a surrounding tubular structure 124 which has a donut like configuration. (It is to be understood that these components 120, 122, and 124 are shown rather schematically herein, and these could take different forms. For example, the tubular liquor collecting structure 124 could be positioned within the digester wall, and other arrangements and configurations could be provided.) In the particular arrangement shown herein, there are four more extraction areas 118 at various vertical locations, each having the strainer 120, extraction passageways 122 and tubular collection structure 124. These other extraction regions 118, are given numerical designations 118, 120, 122 and 124 with letter suffixes "a", "b", "c" and "d" distinguishing the other extraction areas 118 and the components associated therewith.
It is also to be understood that the digester 120 is being shown schematically, and other apparatus and components would be utilized. For example, there would be at the lower end of the digester 102, means for possibly introducing wash water or other liquid possibly for changing the temperature, diluting the pulp slurry for subsequent processing or other purposes. Also components such as shown in FIG. 1 would likely be utilized as components for use with the present invention.
There is for each extraction area 118 a related discharge valve 126, and these valves 126 are also given letter suffixes indicating which of the extraction areas 118 these are associated. Most of these valves 126 direct the liquor in a recirculating pattern so that the liquor may be introduced back into the digester at a higher location. The extraction valve 126b (and/or possibly another valve or valves 126) may, depending upon other processing functions, lead the liquor directly to the evaporator.
All of the components 102 through 126 which have been described thus far are or may be, rather similar to or the same as in a typical prior art digester, such as shown at 14 in FIG. 1. In fact, one of the benefits of the present invention is that the system of the present invention can quite advantageously be incorporated into an existing digester, such as shown in FIG. 1. From this point on, the components of the digester system 100 described in the following text with reference to FIG. 2 are those which are newly added as part of the present invention.
There is a solvent tank 130 having in the upper portion of the tank 130 a steam region 132 containing high pressure steam that is at a pressure higher than the operating pressure inside the digester 102. In the lower part of the solvent tank 130 there is a section containing a solvent composition 134. There is also a solvent recirculating tank 136 having an upper high pressure steam region 138 and a lower solvent containing region 140, and also a third solvent tank which is a solvent makeup tank 142, having an upper steam region 144 and a lower solvent region 146. There is a source of high pressure steam indicated at 148, leading into a steam line 149 that communicates with each of the aforementioned solvent tanks 130, 136 and 142 through steam inlets 150, 152, and 154, respectively. The inlets 152 and 154 each have control valves 156 and 158, respectively, and another valve 159 is provided in the line 149 upstream of the steam inlet 150.
The system of the present invention will first be described with reference to the upper liquor extracting area 118. There is a steam inlet valve 160 which leads from the steam line portion 162 into the uppermost tubular container 124, and a solvent outlet valve 164 leading from the container 124.
Also, there is for the first liquor extraction region 118 a solvent supply valve 166 leading from the lower solvent region of the tank 130, and into a discharge line 168 which leads from the tubular container 124 to the liquor discharge valve 126.
In this preferred embodiment, let it be assumed that the digesting liquor has as its primary digesting ingredient alcohol (either ethyl or methyl). In the prior art, when ethyl or methyl alcohol is used as the primary digesting ingredient, if certain types of wood are being processed (e.g. wood chips made from soft wood), the reaction of the liquor with the wood chips is such as to be more prone to cause scaling to form on the strainer 120.
With reference to FIGS. 3 and 4, which show a portion of the strainer 120, it can be seen that the strainer 120 comprises a plurality of elongate metal strainer elements 170, each having a front or inner face 172, facing the pulp slurry 174 and a back face 176. In cross section, each strainer element 170 has converging sidewalls 178 which converge from the wider upstream face 172 to the smaller downstream face 176. The openings 180 defined by adjacent front surfaces 172 could be, for example, 1/16th of an inch in width.
The deposit of the scaling generally occurs at the front edge portions of the front faces 172, such as circled at 182. In prior art alcohol based digester systems, the deposit of scaling on the screen elements 170 is substantially inhibited (if not substantially eliminated) by formulating the liquor so that it contains an adequate amount of sodium hydroxide (NaOH) to prevent the scaling. When this is done, the spent liquor (i.e. black liquor) that is removed from the digester (or from washers later on in the pulp processing) is commonly processed so as to isolate the sodium hydroxide (and possibly other processing chemicals) for reuse in the digesting system. This is commonly done by first evaporating a substantial portion of the water from the black liquor and then burning the concentrated black liquor so that the useful chemicals can be extracted from the remaining residue.
To describe the process of the present invention, there is used an alcohol based liquor where either ethyl or methyl alcohol is used as the primary digesting ingredients. The formulation for the white liquor has little, if any, sodium hydroxide. Thus, it would be expected that after a relatively short period of operation, possibly one or two weeks, the screens 120, 120a, etc. would become clogged due to the deposit of scaling. To alleviate this, the following process is performed in the present invention. This process in general involves frequent periodic solvent applications for the strainers 120, 120a etc. sequentially.
The first step is to open the steam valve 160 to direct the high pressure steam into the tubular container 124. At this time, the liquor discharge valve 126 is open. The effect of this high pressure steam is to drive part of this liquor out of the tubular container 124 back into the digester 102, and also to drive the rest of the liquor through the recirculating valve 126, which at this time remains open. This valve 126 conventionally recirculates the liquor back through a heater to the top of the digester 102.
When the tubular container 124 is substantially empty of liquor, then the valve 126 is closed. The solvent supply valve 166 is opened to direct solvent 134 from the solvent region in the tank 130 to the tubular containing structure 124 so that, with the solvent at 134 being at the pressure of the steam 132, the solvent fills the tubular container 124 and passes into the digester 102 to flow inwardly through the passageways 184 in the strainer 120 a short distance and to some extent into the pulp slurry 174. In this particular embodiment, the solvent at 134 has as its main ingredient (or at least as one of its main ingredients) sodium hydroxide which dissolves any small amount of scaling that might have accumulated at the critical edge locations 182 of the strainer elements 170. Since the solvent moves through the entire tubular container 124, it passes through the strainer 120 around the entire circumference thereof.
After a period of time (e.g. five to ten minutes,) the valve 166 is closed and the valve 164 is opened to drain the solvent in the tubular container 124 downwardly through a line 186 to the lower region 140 of the recirculating tank 136. During this time, the valve 160 remains open so that most of the solvent is driven from the tubular container 124 down to the recirculating tank so as to essentially empty the tubular container 124. When this is completed, the valve 160 is closed, the valve 164 is closed, and the valve 126 is opened so that the liquor from the digester 102 flows outwardly from the digester to the valve 126 to be recirculated back to the digester.
Thus, it can be seen that periodically, for a short period of time, a certain portion of solvent is circulated from the tank 130 to the container 124 and in a counterflow direction through the strainer 120 to cause removal of what scaling may have accumulated in the previous time period (e.g. possibly two hours or so, which is an approximate time between sequential cleaning operations). A certain amount of this solvent will remain in the pulp within the digester, near the sidewalls of the digester, and this will simply flow downwardly with the pulp. This small amount of solvent would not have any substantial effect on the overall digesting process and subsequent processes in the pulp mill.
After the descaling operation has been completed at the upper recirculating region 118, then the very same process is done with respect to each of the other recirculating regions 118a, 118b, etc., in sequence. Since substantially the same sequence is followed as is described above, this will not be repeated relative to the recirculating region 118a-d.
As solvent is used, it will be necessary to take solvent from the makeup tank 142. The makeup tank 142 is desirably provided with solvent in a batch operation. To accomplish this, the steam valve 158 and the solvent discharge valve 192 would be closed, and the makeup valve 190 opened to direct the make-up solvent into the tank 142. Then the valve 190 is closed, and the steam valve 158 and valve 192 are opened to direct the solvent from the region 146 over to the recirculating tank 136.
To recirculate the solvent that has been collected in the tank 136, there is provided a pump 194 that directs the solvent through a valve 196 back to the tank 130.
It can be seen that with the present invention, the strainers 120, 120a, etc., by being cleaned by solvent for short periods at frequent intervals, can be maintained substantially free of scaling for continuous operation of the pulp mill. With very little sodium hydroxide introduced into the liquor, this opens various avenues for other uses of the spent black liquor other than burning it for recovery of the sodium hydroxide and other chemicals. The alcohol which is used as the main digesting ingredient and which remains in the liquor can be recycled through evaporation, and the residue from the black liquor could advantageously be put to uses other than fuel. As indicated previously, this could be used as a binder or ingredient for various products, such as structural panels, animal feed, or other uses.
It is to be understood that while sodium hydroxide has been described for a preferred ingredient for the solvent, and while the present invention is particularly well adapted for use in an alcohol digesting system, within the broader scope of the present invention, there could be modifications and applications of the present invention with other materials which would be such as to be suitable for or compatible with, the main operating features of the present inventions.
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A wood pulp digester comprising a containing structure defining a digesting chamber in which wood chips and processing liquor are contained under pressure. Liquor is moved from a liquor removal region in the digester through a strainer. Periodically a cleaning solvent is directed under pressure in a counterflow direction through the strainer to remove scaling that may tend to accumulate on the strainer.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority under 35 U.S.C. §119 of U.S. Provisional Application Ser. No. 61/562622 filed on Nov. 22, 2011, the content of which is relied upon and incorporated herein by reference in its entirety.
BACKGROUND
[0002] The products and methods of the present disclosure relate generally to glass enclosures and more particularly to enclosures and enclosure elements for consumer electronic devices such as computers, cellphones, media players, and televisions.
TECHNICAL BACKGROUND
[0003] Enclosures for consumer electronic devices are designed to meet stylistic as well as functional requirements. Key functional requirements include physical durability and environmental stability, the latter most importantly including resistance to moisture but also resistance to electrical, chemical and thermal environmental factors.
[0004] At present, meeting all of the requirements for consumer electronics enclosures involves the mating of diverse glass, metal and plastic enclosure elements. Plastic parts offer a high degree of shape flexibility and can be designed to provide adequate impact resistance for some enclosure components, but are highly susceptible to damage from abrasion. Metals offer good physical durability but are difficult to shape, are prone to scratching and denting damage, and are subject to corrosion in harsh chemical environments.
[0005] Glass imparts the essential characteristic of transparency to advanced consumer electronics devices, including the vast majority of products that increasingly incorporate video display and/or touch screen control functionality as central features. Glass offers a high level of resistance to chemical attack and scratch-related damage, and in advanced forms provides reasonable resistance to bending or impact fracture damage as well. Thus it is the preferred construction material for video display substrates, protective faceplates for video displays, and touch screen substrates for electronic device control screens.
[0006] Notwithstanding the wide range of materials available for the design and construction of enclosures for these devices, problems relating to enclosure durability and environmental stability remain. One problem is that the available materials differ widely in physical and chemical properties. Assembling device enclosures from two or more materials of differing thermal expansion, hardness, rigidity, machinability and/or bonding characteristics therefore presents an array of mating problems that lead to limits on the ability of the assemblies to retain physical and environmental integrity over reasonable service lifetimes. Thus there remains a need for improved enclosure designs of reduced complexity as well as improved durability and functional stability.
SUMMARY
[0007] The present invention provides electronic device enclosures and components for such enclosures that address many of the above-noted problems with conventional enclosures. The enclosures of the invention are formed predominantly of a single construction material, i.e., a strengthened glass, that glass combining high impact resistance with high bending strength so as to provide good mechanical durability as well as transparency and environmental durability. The enclosure designs are three-dimensional (3D), comprising glass front (or top), back (or bottom), and side enclosure members. Enclosures formed primarily of glass in accordance with the present disclosure can be designed to encase consumer electronic devices ranging in size from cellphones to televisions, and are particularly well adapted for use in the manufacture of mid-size devices such as laptop or tablet computers which are presently designed to combine high-definition display and touch screen control functionality in a single video display faceplate.
[0008] In particular embodiments, glass enclosures for electronic devices provided in accordance with the present disclosure comprise a generally planar glass base member connecting with an encircling glass side wall member to form a unitary glass container of a predetermined depth. For the purposes of the present description “generally planar” members include flat as well as slightly curved sheet structures, slightly curved meaning embodying large-radius cylindrical or spherical (three-dimensional) curvature as hereinafter more fully described. A generally planar glass cover member is permanently bonded to the encircling glass side wall member of the container to form an enclosed volume of a predetermined depth and of a size and shape selected for the enclosure of an electronic device. Access to the enclosed volume for the insertion of electronic components is provided by an opening or openings in the glass side wall member, e.g., by encircling only three of four sides in the case of a square or rectangular enclosure.
[0009] The unitary glass container defining the enclosed volume incorporates at least a first ion-exchanged surface compression layer of a first uniform depth extending over at least the exterior surface of the container, while the generally planar glass cover member incorporates a second ion-exchanged surface compression layer of a second uniform depth extending over at least the outer surface of the cover. The glass enclosure thus provided is absent major metallic and polymeric enclosing segments, i.e., segments enclosing more than one side of the enclosure. Thus the use of the latter materials is generally limited to inserts or ports providing, for example, speaker openings or plugging interfaces for electrical power or data connections.
[0010] As broadly conceived, a glass enclosure such as above described may be constructed of three or even more enclosing members. As an example, the unitary glass container may be constructed of separate base and sidewall members that are then permanently joined or connected with each other via organic adhesives or, more advantageously, a glass-to-glass seal, to form the unitary container. For best integrity, however, the invention provides enclosure embodiments comprising unitary glass containers wherein the encircling glass sidewall member and glass base member are integrally connected, i.e., wherein the glass base member is “integral with” the glass sidewall member, there being no joint or seal between those members. In those embodiments the sidewall portions of the container will merge seamlessly into the glass base portion thereof along angled or curved edges, as can be achieved, for example, by forming the unitary container from a single glass preform.
[0011] In another aspect the invention provides an electronic device comprising electronic components contained within an enclosure constructed of strengthened glass base, sidewall and cover members as above described, and wherein the electronic components include a video display. In particular embodiments of the device, an external surface of at least one of the base, sidewall, and cover members supports an external touch screen for controlling one or more functions of the electronic components.
[0012] In still another aspect the present invention includes a method for making a strengthened glass electronic device enclosure. In accordance with that method, a first softened glass preform, typically a section of softened glass sheet, is formed into a unitary glass container comprising a generally planar base portion and an encircling sidewall portion integral with the base portion, the sidewall portion advantageously joining the base portion at curved (rounded) edges. In particular embodiments, a softened glass sheet is formed into a unitary container comprising a quadrilateral (e.g. square or rectangular) base portion and an encircling sidewall portion integral with the base portion along three of the four edges of the quadrilateral base.
[0013] A second softened glass preform is formed into a cover member for the device enclosure, that cover member also being of a generally planar configuration and a peripheral shape approximately matching the shape of the base portion. Again, the generally planar base portion or cover may be flat or slightly curved, “slight curvature” for the purpose of the present description being limited such that the maximum separation between the surface of a slightly curved cover or base portion and a base plane defined by the edges of the cover or base portion will generally not exceed 10% of the smallest width or breadth of the cover or base.
[0014] The unitary glass container and cover member thus provided are subjected to an ion-exchange strengthening treatment, each such treatment comprising exposing the glass part to a source of exchangeable alkali metal ions for a time and at a temperature sufficient to develop strengthening surface compression layers in each of the glass parts, thus to provide a strengthened glass container and a strengthened glass cover member. The strengthened glass cover member is then attached to the sidewall portion of the strengthened unitary glass container to the form the strengthened glass enclosure. Any means for attaching the cover to the glass container that can provide a strong, stable and moisture-impermeable seal between the cover and container can be used.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The invention is further described below with reference to the appended drawings, wherein:
[0016] FIG. 1 is a photograph presenting a perspective view of a strengthened glass enclosure; and
[0017] FIG. 2 is an illustration of an electronic device comprising a strengthened glass enclosure provided in accordance with an embodiment of the invention.
DETAILED DESCRIPTION
[0018] As noted above, particular embodiments of the strengthened glass enclosures provided according to the present invention comprise base and top members of quadrilateral configuration, as well as embodiments wherein the sidewall member forms at least three sides of a quadrilateral enclosure incorporating such base and top members.
[0019] As illustrated in FIG. 1 of the drawings, one embodiments of a strengthened glass enclosure 10 provided in accordance with the invention may comprise an encircling (u-shaped) strengthened glass sidewall member 12 making up three sides 12 a, 12 b and 12 c of the enclosure, that member being permanently bonded along the three sides to a quadrilateral (rectangular) strengthened glass base member 14 to form a unitary glass container. Sidewall 12 may be permanently bonded to base member 14 by means, for example, of a cured organic adhesive (e.g., a polymeric seal) or a glass frit seal, not shown, such that a unitary four-sided glass container (i.e., comprising the base and three sides) of a predetermined depth D is provided. The sidewall member and base portions 12 and 14 are subjected separately to an ion-exchange strengthening treatment prior to assembly where an organic adhesive is to be used for assembling those portions into the container.
[0020] Permanently bonded to the upper edges of sides 12 a, 12 b and 12 c to form a strengthened glass enclosure for an electronic device is a rectangular strengthened glass cover member 16 . Cover member 16 is subjected to an ion-exchange strengthening treatment prior to bonding if an organic adhesive is employed to form the permanent bond.
[0021] A useful organic adhesive for the bonding the base 14 and cover member 16 to the sidewall is a UV curable adhesive such as Vitralit® 7105 adhesive, commercially available from Panacol-Elosol GmbH, Steinbach/Taunus, Germany. If the glass enclosure is to be assembled and permanently bonded prior to ion-exchange strengthening, then a refractory inorganic bond of conventional type, such as a glass frit seal, should be used for bonding. For the purposes of the present description the base and cover members may hereinafter be interchangeably designated as top or front faces and bottom or back faces, such designations simply depending upon the device to be enclosed and the way in which the enclosed device will be oriented in use.
[0022] As further illustrated in FIG. 1 , a strengthened glass enclosure produced as described may be provided with a temporary supporting member such as an internal glass or plastic supporting spacer 18 . Such a spacer may suitably be of a height corresponding to the predetermined depth D of the unitary glass container, that depth suitably being in the range of 3-50 mm, and may be positioned between the base and cover members, for example proximate to the side opening 18 s of the enclosure, in order to reduce bending stresses on the adjacent unattached edges 14 a and 16 a of base member 14 and cover member 16 . Alternatively or in addition, a closing and supporting spacer, e.g., a spacer partially or totally enclosing the side opening not closed by sidewall 12 , may be inserted. In some embodiments such a closing spacer may provide speaker openings or plugging interfaces for the enclosed electronic device.
[0023] The development of first and second ion-exchanged surface compression layers of a suitable thickness on the surfaces of the glass components of the strengthened glass enclosure can be secured through the use ion-exchange-strengthenable alkali aluminosilicate glasses. In particular embodiments of the disclosed enclosures, each of the first and second ion-exchanged surface compression layers have a thickness of at least 30 μm and a peak surface compression level of at least 500 MPa. These levels of surface compression enable the use of glass base, sidewall and cover members of relatively slight thickness, i.e., thicknesses in the range of 500-2000 μm.
[0024] Glasses having good forming capabilities and capable of providing surface compression layers of adequate stress and thickness via a potassium-for-sodium ion-exchange are known. Examples thereof include alkali aluminosilicate glasses comprising at least about 10% sodium oxide by weight, in some embodiments 12-15% sodium oxide by weight, and having a liquidus viscosity of at least about 1000 Kp, in some embodiments 1000-5000 Kp. Corning Code 2317 and 2318 glasses, commercially available from Corning Incorporated, Corning, N.Y., USA are examples of suitable glasses. Chemically strengthened enclosure components formed of such glasses can provide excellent transparency as well as polished surfaces of good optical quality and high resistance to chipping and scratching damage. In addition they can support surface decorations or surface coloration or texturing on inner or outer surfaces of the enclosures, such that even low-cost inner surface printing methods can provide permanent decorative features.
[0025] The herein-disclosed method for providing a strengthened glass enclosure in accordance with the invention offers particular advantages for the production of electronic device enclosures in terms of product integrity and processing efficiency. The advantages of that method result from the fact that the unitary glass container for assembling the enclosure is 3D-formed as a one-piece unit by shaping a single softened glass preform into a container comprising a generally planar base portion integrated with an encircling sidewall portion. This one-piece unit, together with a planar cover member, is then subjected to ion-exchange strengthening either before or after assembly into a completed enclosure depending upon the particular sealing method to be used.
[0026] The glass-forming method employed to form the container and cover is not critical; any of the known casting, pressing, spinning or blowing methods could in principle be used. However, in view of the slight thicknesses of the enclosure components to be used, the softened glass preforms are typically provided in the form of sections of drawn glass sheet of near-optical surface finish, and the shaping of such sheet sections is most efficiently carried out by means of sheet reforming methods such as pressing or vacuum sagging into molds of a configuration matching the desired enclosure component. The enclosures can then be assembled from the containers and cover members via conventional fastening techniques, including for example by metal clipping or permanent adhesive tape. It is generally desirable to avoid glass-to-glass contact between the containers and covers, and so thin, invisible polymer interfaces can be used permanent frit sealing methods are not practicable.
[0027] For device applications where high mechanical stresses or shock are expected, enclosure designs providing enhanced stiffness are utilized. As one approach for stiffness enhancement, the U-shaped sidewall member providing sides 12 a, 12 b and 12 c of FIG. 1 of the drawings comprises sidewall corners that are smoothly curved into one another, thus exhibiting lower corner stresses under applied strains than those with sharply angled corners. Additional strengthening can be conveniently provided in accordance with the above method for one-piece container forming by using a mold or other shaping means to form a container shape wherein the encircling glass sidewall portion merges into the glass base portion along curved edges as above described. Curved edges having curvature radii in the range of 2-20 mm are suitable for that purpose.
[0028] Yet another design choice offering additional enclosure stiffening is that of adding slight curvature to components of the enclosure. In particular embodiments, strengthened glass enclosures are provided wherein at least one of the glass base member or base portion and the glass cover member exhibits slight convex or concave curvature as above defined.
[0029] FIG. 2 of the drawings presents a perspective view, not in true proportion or to scale, of an electronic device employing an enclosure design incorporating curved enclosure components for added strength as described. In the drawing of FIG. 2 , an electronic device 30 comprises a strengthened glass enclosure 20 incorporating an encircling sidewall member 22 having rounded corners 22 r to reduce sidewall corner stresses as above disclosed. Rounded corners 22 r are curved to match rounded corners 26 r of cover member 26 which is bonded to sidewall member 22 . Also to enhance enclosure rigidity, base portion 24 of enclosure 20 merges into and is integral with sidewall portion 22 along rounded edges 24 r, and base portion 24 is provided with a slight convex (outward) curvature as indicated by the departure of base portion front edge 24 a from an imaginary flat base line 24 f and from cover member front edge 26 a.
[0030] The electronic device 30 of FIG. 2 incorporating glass enclosure 20 as above configured is a portable media player comprising a video display component as part of electronic circuitry 40 disposed within the enclosure. Strengthened glass cover member 26 of enclosure provides transparent protection for the display and other components of electronic circuitry 40 , and also supports a transparent electronic touch screen on its external surface for controlling one or more functions of that electronic circuitry.
[0031] Strengthened glass enclosures such as provided in accordance with the invention can be produced over a wide range of sizes and shapes depending only upon the sizes and shapes of the electronic devices to be enclosed. Enclosure transparency provides an obvious advantage whenever the electronic circuitry to be enclosed includes video display components, while strength and resistance to cosmetic damage favor their use for the protection of portable electronic devices, e.g., devices wherein the enclosed electronic circuitry comprises components for a laptop or tablet computer, a telephone, a camera, or a media player. Enclosures having enclosed volumes in the range of 90-7500 cm 3 can easily accommodate a wide variety of such circuitry. Further, the desirable electric properties of these glasses make the enclosures well suited for the construction of devices wherein at least one of the glass base member and the glass top member supports an external touch screen for controlling the electronic circuitry.
[0032] While the invention has been described above with respect to particular examples of materials, designs and methods it will be recognized that those examples have been presented for purposes of illustration only, and that a wide variety of other embodiments may adapted to meet the needs of present or future applications within the scope of the appended claims.
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A 3-D glass enclosure comprises a generally planar glass base member, an encircling glass side wall member connected to the base member, and a generally planar glass cover member connected to the side wall member to form a unitary glass enclosure, the base, sidewall and cover members being made by reforming softened glass sheet preforms and subjecting the reformed members to ion-exchange strengthening, thus providing strong transparent enclosures for electronic devices such as tablet computers, cellphones, media players and televisions.
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