Processing machine and methods for processing dip-molded articles

Abstract

Processes for the manufacturing of dip-molded articles can include the application of compression to remove molding materials from within the dip-molded articles. In some embodiments, inflatable implantable medical devices are dip-molded and can be manufactured using such compression processes.

Claims

1. A dip-molded article processing machine comprising: a first conveyor assembly defining a first conveyor surface; a first compression section comprising one or more compression rollers with an outer peripheral surface spaced apart from the first conveyor surface by a first gap distance, the compression rollers configured to directly contact the dip-molded article; a second compression section comprising a second conveyor assembly defining a second conveyor surface, the second conveyor surface facing the first conveyor surface and spaced apart from the first conveyor surface by a second gap distance, wherein the first gap distance is greater than a minimum gap distance of the second gap distance; and at least one an electric motor that, when actuated, concurrently drives the first conveyor assembly, the one or more compression rollers, and the second conveyor assembly.

2. The machine of claim 1, wherein the first conveyor surface and the second conveyor surface are generally planar, non-parallel surfaces.

3. The machine of claim 1, wherein the second gap distance decreases along the longitudinal length of the second conveyor surface.

4. The machine of claim 1, wherein the second gap distance monotonically decreases along the longitudinal length of the second conveyor surface.

5. The machine of claim 1, further comprising a power source configured to concurrently drive the first conveyor assembly, the one or more compression rollers, and the second conveyor assembly at a substantially equal linear speed.

6. The machine of claim 1, wherein at least one of the first gap distance and the second gap distance are adjustable.

7. The machine of claim 1, wherein the second gap distance differs along a longitudinal length of the second conveyor surface.

8. The machine of claim 1, further comprising one or more additional conveyor surfaces facing the first conveyor surface.

9. The machine of claim 8, wherein the first conveyor surface is longer than a combined length of the second conveyor surface and the one or more additional conveyor surfaces.

10. A dip-molded article processing machine comprising: a first conveyor assembly defining a first conveyor surface; a first compression section comprising one or more compression rollers with an outer peripheral surface spaced apart from the first conveyor surface by a first gap distance; the compression rollers configured to directly contact the dip-molded article; a second compression section comprising a second conveyor assembly defining a second conveyor surface, the second conveyor surface facing the first conveyor surface and spaced apart from the first conveyor surface by a second gap distance, wherein the first conveyor surface is longer than the second conveyor surface; and at least one an electric motor that, when actuated, concurrently drives the first conveyor assembly, the one or more compression rollers, and the second conveyor assembly.

11. The machine of claim 10, wherein the first conveyor surface and the second conveyor surface are generally planar, non-parallel surfaces.

12. The machine of claim 10, wherein the second gap distance decreases along the longitudinal length of the second conveyor surface.

13. The machine of claim 10, wherein the second gap distance monotonically decreases along the longitudinal length of the second conveyor surface.

14. The machine of claim 10, further comprising a power source configured to concurrently drive the first conveyor assembly, the one or more rollers, and the second conveyor assembly at a substantially equal linear speed.

15. The machine of claim 10, wherein at least one of the first gap distance and the second gap distance are adjustable.

16. The machine of claim 10, wherein the second gap distance differs along a longitudinal length of the second conveyor surface.

17. The machine of claim 10, further comprising one or more additional conveyor surfaces facing the first conveyor surface.

18. A dip-molded article processing machine comprising: a first conveyor assembly defining a first conveyor surface; a first compression section comprising one or more compression rollers with an outer peripheral surface spaced apart from the first conveyor surface by a first gap distance, the compression rollers configured to directly contact the dip-molded article; a second compression section comprising a second conveyor assembly defining a second conveyor surface, the second conveyor surface facing the first conveyor surface and spaced apart from the first conveyor surface by a second gap distance; and at least one manual crank mechanism that, when rotated, concurrently drives the first conveyor assembly, the one or more rollers, and the second conveyor assembly.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Some embodiments of the invention are herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of embodiments of the invention. In this regard, the description taken with the drawings makes apparent to those skilled in the art how embodiments of the invention may be practiced.

(2) In the drawings:

(3) FIG. 1 is a schematic representation of a dip molding process;

(4) FIG. 2 is a schematic representation of a dip-molded article (within which a semi-solid molding material is contained) made by the dip molding process of FIG. 1;

(5) FIGS. 3 and 4 schematically represent a process for compressively expelling the semi-solid molding material out of the dip-molded article of FIG. 2;

(6) FIG. 5 is a perspective view of an example processing machine for compressively expelling a semi-solid molding material out of a dip-molded article;

(7) FIG. 6 is a perspective longitudinal cross-sectional view of the processing machine of FIG. 5;

(8) FIG. 7 is a side view of the processing machine of FIG. 5; and

(9) FIG. 8 is a perspective view of the processing machine of FIG. 5 shown in a different configuration.

(10) Like reference numbers represent corresponding parts throughout.

DETAILED DESCRIPTION

(11) Some devices, such as, but not limited to, inflatable implantable medical devices, are manufactured using a dip molding process. While the disclosure provided herein is described in the context of inflatable implantable medical devices, many other types of articles other than inflatable implantable medical devices are also manufactured using dip molded processes, and are just as relevant to the subject matter described herein. Dip molding is performed by submerging a mold that will form the inside of the resulting article into a liquid material. A layer of the material coats the mold to form the article. After the material is sufficiently cured, the dip-molded article is separated from the mold.

(12) The configurations of some dip-molded articles preclude the use of a rigid mold because the molded article cannot be stripped from the rigid mold without damaging the article. For example, some balloon-like inflatable medical devices have a small orifice in comparison to the size of its internal space that is created by the mold. Hence, removing a rigid mold from the internal space through the small orifice may be difficult or impossible without tearing the molded polymer article. In some cases, therefore, the mold is made at least partially from a material that can be converted or broken down into a flowable state or condition (as used herein, “flowable state” or “flowable condition” refers to a semi-solid material that is capable of being extracted through an orifice). While the molding material is in the flowable condition, the molding material can be gradually expelled out of the small orifice without damaging the molded polymer article. FIGS. 1-4 schematically represent such a process of manufacturing a polymer article.

(13) Referring to FIG. 1, a simplified version of a dip molding process 100 is represented. For example, the dip molding process 100 can be performed using a polymer source 110 and a mold 120. The polymer source 110 (e.g., vat, tank, reservoir, etc.) contains a liquid polymer (e.g., silicone, plastisol, latex, neoprene, urethane, and other polymer dispersions or solutions). The mold 120 can be fully or partially submerged into the liquid polymer. After a period of time, the mold 120 is withdrawn from the polymer source 110, and a layer of the polymer will be covering the mold 120 (to the extent that the mold 120 was submerged in the polymer). After the polymer layer is sufficiently cured (i.e., solidified), the mold 120 will be removed from within the polymer (as described further below), resulting in a dip-molded polymeric article.

(14) In the depicted example, the mold 120 includes a holder 122 and a mold member 124. The mold member 124 is removably attached to the holder 122. In this illustrative example, the mold member 124 is shaped as a disk and the holder 122 is an elongate shaft. It should be understood that the size and shape of the mold member 124 are selected in accordance with the desired attributes of the final dip-molded article that is to be made using the mold member 124. Hence, while the mold member 124 is a disk in this example, it should be understood that the concepts described herein are by no means limited to disk-shaped articles.

(15) While in some cases rigid molds are used for dip molding processes, the mold member 124 of dip molding process 100 is made of a material that can later be converted into a flowable condition to facilitate its removal from within the dip-molded article. For example, in some cases the mold member 124 can be made of agar material which is a contiguous semi-solid gel-like substance at room temperature. In addition to agar, other materials such as, but not limited to, polysaccharides (e.g., alginates, carrageenan, pectin, chitosan, and agarose) and polymers such as hyaluronic acid albumin and gelatin may be used to make the mold member 124 in some cases.

(16) The holder 122 is used to manipulate the mold member 124. For example, the holder 122 can be used as a handle for dipping the mold member 124 into the polymer source 110.

(17) After removing the mold 120 from the polymer source 110, the coating on the mold 120 is given a chance to cure. Then the holder 122 is separated from the mold member 124.

(18) Referring also to FIG. 2, after separating the holder 122, a resulting assembly 130 includes the mold member 124 surrounded by a dip-molded article 140. The dip-molded article 140 is a thin, continuous layer of flexible material (e.g., polymer in some embodiments) that adhered to the mold member 124 during the dip molding process 100. Hence, the dip-molded article 140 resembles the size and shape of the mold member 124, which in this example means the dip-molded article 140 resembles a disk-shaped balloon. The dip-molded article 140 includes a small orifice 142 that was created by the holder 122 during the dip molding process 100.

(19) The next step of the process represented in FIGS. 1-4 is to remove the mold member 124 from the interior of the dip-molded article 140.

(20) Referring also to FIG. 3, in this example process the assembly 130 is then placed within a flexible container 150 (shown transparently here). The flexible container 150 can be a sealable polymer bag, for example. The flexible container 150 will serve to protect the dip-molded article 140 during the removal of the mold member 124, and will serve to contain the material of the mold member 124 after it is expelled from within the dip-molded article 140.

(21) With the assembly 130 located within the flexible container 150, compression is applied to the assembly 130 (as described further below) to expel the material of the mold member 124 from within the dip-molded article 140. The material of the mold member 124 will be expelled through the orifice 142, without damaging the dip-molded article 140. Hence, the compression process converts the semi-solid gel-like mold member 124 to a flowable/extractable state to facilitate its removal from the dip-molded article 140 via the orifice 142.

(22) Referring also to FIG. 4, after the compression has expelled the mold member 124 material from the dip-molded article 140, the dip-molded article 140 is substantially void of the material of the mold member 124. The material of the mold member 124 that was expelled from within the dip-molded article 140 is neatly contained within the flexible container 150. Thereafter, the dip-molded article 140, being substantially void of the material of the mold member 124, can be removed from the flexible container 150 for further processing (e.g., rinsing, etc.).

(23) Referring to FIG. 5, an example machine 200 for compressively processing dip-molded articles containing semi-solid molding material includes an input end 202 and an output end 204. Broadly summarizing the function of the machine 200, the arrangement depicted in FIG. 3 can be inserted into the machine 200 at the input end 202 (with the orifice of the dip-molded article extending generally opposite to the direction the dip-molded article will travel through the machine 200), and the arrangement depicted in FIG. 4 will be ejected from the machine 200 at the output end 204. Between the input end 202 and the output end 204 are a series of mechanisms that apply compression to the dip-molded articles containing the semi-solid molding material. In result, the molding material is expelled from within the dip-molded articles.

(24) Referring also to the longitudinal cross-sectional view of the machine 200 shown in FIG. 6, the machine 200 includes a first conveyor assembly 210. In the depicted embodiment, the first conveyor assembly 210 includes a first conveyor belt surface 212 that extends from the input end 202 to the output end 204. The first conveyor surface 212 provides a surface on which a flexible container holding a dip-molded article containing semi-solid molding material (e.g., as shown in FIG. 3) can be positioned while advancing through the machine 200. In some embodiments, the first conveyor surface 212 is a generally planar surface.

(25) For the sake of brevity and clarity, hereafter: (i) the materials and arrangement of FIG. 3 will be referred to as the “pre-processed arrangement,” (ii) the materials and arrangement that have received compression from machine 200 but prior to the expulsion of all molding material from the dip-molded article will be referred to as the “mid-processing arrangement,” and (iii) the materials and arrangement of FIG. 4 will be referred to as the “post-processed arrangement.” Collectively, the pre-processed arrangement, the mid-processing arrangement, and the post-processed arrangement will hereafter be referred to as the “work-in-process material” or “WIP material.”

(26) The first conveyor assembly 210 conveys the WIP material through the machine 200. In some embodiments, an electric motor is used as the power source for the conveyance. In some embodiments, manual exertion by a human operator is used as the power source for the conveyance. In some embodiments, a backing plate below the first conveyor belt surface 212 may be included to provide a stable foundation of support for the WIP material as it receives compression by the machine 200.

(27) In some embodiments, the speed at which the first conveyor assembly 210 conveys the WIP material through the machine 200 results in a cycle time (i.e., the time to convert the pre-processed arrangement to the post-processed arrangement) ranging from about one minutes to about five minutes, or about 10 seconds to about three minutes, or about two minutes to about ten minutes, or any amount of time within those ranges, or any time more than ten minutes. In some embodiments, the speed is adjustable. In some embodiments, the speed is non-adjustable. In some embodiments, the speed may automatically vary depending on the location of the WIP material within the machine 200. In some cases, the speed is selected to be slow enough to substantially prevent incurring damage to the molded dip-molded article as the material of the mold member is expelled from the article.

(28) In the depicted non-limiting example, the machine 200 includes a first compression section 220 and a second compression section 240. The first compression section 220 is nearer to the input end 202 than is the second compression section 240. Conversely, the second compression section 240 is nearer to the output end 204 than is the first compression section 220. Accordingly, as the WIP material advances through the machine 200 from the input end 202 to the output end 204, the WIP material first encounters the first compression section 220 and then subsequently encounters the second compression section 240.

(29) The first compression section 220 converts the semi-solid gel-like material of the mold member in the pre-processed arrangement (e.g., mold member 124 of FIG. 3) into a flowable/extractable state. This is done in preparation for the later expulsion of the molding material from the dip-molded article. In other words, the first compression section 220 crushes and breaks up the continuity of the semi-solid gel-like material of the mold member to form pieces of the material that are suitable to be further processed by the second compression section 240. The second compression section processes the material into pieces that are small enough to fit through the orifice of the dip-molded article in a flowable/extractable manner.

(30) In the depicted embodiment, the first compression section 220 includes a first compression roller 222a, a second compression roller 222b, and a third compression roller 222c. While the first compression section 220 of the depicted embodiment includes three compression rollers 222a, 222b, and 222c, in some embodiments one, two, four, five, six, seven, eight, nine, ten, or more than ten compression rollers are included.

(31) In some embodiments, the compression rollers 222a, 222b, and 222c are driven rollers. That is, in some embodiments the compression rollers 222a, 222b, and 222c are rotationally driven by a motor or manual power. In some embodiments, the compression rollers 222a, 222b, and 222c are driven at a rotational speed that results in a surface speed on the periphery of the compression rollers 222a, 222b, and 222c that is substantially equal to the surface speed of the first conveyor belt 212. In some embodiments, the compression rollers 222a, 222b, and 222c are driven at a rotational speed that results in a surface speed on the periphery of the compression rollers 222a, 222b, and 222c that is less than or greater than the surface speed of the first conveyor surface 212. In some embodiments, the compression rollers 222a, 222b, and 222c are driven at a rotational speed that is variable and/or adjustable in relation to (or not in relation to) the surface speed of the first conveyor surface 212. In some embodiments, the compression rollers 222a, 222b, and 222c are not driven, but rather are idler rollers that may or may not turn in response to the WIP material being advanced by the first conveyor assembly 210.

(32) In the depicted embodiment, the compression rollers 222a, 222b, and 222c are generally cylindrical with generally smooth outer surfaces. In some embodiments, one or more of the compression rollers 222a, 222b, and 222c may have shapes other than cylindrical and/or may have outer surfaces that are not smooth. For example, in some embodiments one or more of the compression rollers 222a, 222b, and 222c may have a polygonal, oval, or other regular or irregular cross-sectional shapes. In some embodiments, the outer surface of one or more of the compression rollers 222a, 222b, and 222c may include asperities, projections, texturing, knurling, and the like.

(33) In some embodiments, the gap spaces between the compression rollers 222a, 222b, and 222c and the first conveyor surface 212 are all substantially equal to each other. In some embodiments, the gap space between one or more of the compression rollers 222a, 222b, and 222c and the first conveyor surface 212 may differ from the gap space between one or more of the other compression rollers 222a, 222b, and 222c and the first conveyor surface 212. For example, in some embodiments the gap spaces between the compression rollers 222a, 222b, and 222c and the first conveyor surface 212 may be progressively smaller as the WIP material is advanced (i.e., the gap space of the compression roller 222a being the largest, the gap space of the compression roller 222c being the smallest, and the gap space of the compression roller 222b being between the gap spaces of the compression rollers 222a and 222c). In some embodiments, the gap spaces of one or more (or all) of the compression rollers 222a, 222b, and 222c are adjustable (either individually or jointly). Any and all such aforementioned variations, and logical extrapolations thereof, pertaining to the first compression section 220 are envisioned, and are within the scope of this disclosure.

(34) In some embodiments, the gap space between one or more (or all) of the compression rollers 222a, 222b, and 222c and the first conveyor surface 212 may be in a range, without limitation, from about 4 mm to about 6 mm, or about 3 mm to about 7 mm, or about 2 mm to about 8 mm, or about 4 mm to about 12 mm, or about 4 mm to about 10 mm, or about 4 mm to about 8 mm, or about 1 mm to about 6 mm.

(35) In some embodiments, the machine 200 may include a warming device (e.g., infrared, ultrasonic, radiofrequency, microwave, radiator with water tank, etc.) that raises the temperature of the WIP material to make the material of the mold member less viscous (i.e., more flowable/extractable).

(36) Still referring to FIGS. 5 and 6, the machine 200 also includes the second compression section 240. The second compression section 240 includes a second conveyor assembly 241 with a second conveyor surface 242. In some embodiments, the second conveyor surface 242 is generally planar. At least a portion of the second conveyor surface 242 faces the first conveyor surface 212 and is spaced apart from the first conveyor surface 212 so that the WIP material can be located therebetween. In some embodiments, the generally planar first conveyor surface 212 is non-parallel to the generally planar second conveyor surface 242.

(37) The second compression section 240 applies a progressively increasing amount of compression to the WIP material as the WIP material is advanced along the second compression section 240. Accordingly, the material of the mold member within the dip-molded article is gradually expelled from the article as the WIP material advances along the second compression section 240.

(38) In some embodiments, the gap spacing between the second conveyor surface 242 and the first conveyor surface 212 differs or is inconsistent along the length of the second conveyor surface 242. For example, in some embodiments the gap spacing between the second conveyor surface 242 and the first conveyor surface 212 decreases along the length of the second conveyor surface 242 (in the direction from the input end 202 toward the output end 204). In some embodiments, the gap spacing between the second conveyor surface 242 and the first conveyor surface 212 decreases monotonically along the length of the second conveyor surface 242. In some embodiments, the gap spacing between the second conveyor surface 242 and the first conveyor surface 212 decreases linearly along the length of the second conveyor surface 242. In some embodiments, the gap spacing between the second conveyor surface 242 and the first conveyor surface 212 decreases non-linearly along the length of the second conveyor surface 242. In some embodiments, the gap spacing between the second conveyor surface 242 and the first conveyor surface 212 is adjustable.

(39) In some embodiments, the gap spacing between the second conveyor surface 242 and the first conveyor surface 212 is in a range of about 5 mm to about 6 mm at the widest spacing (e.g., at the initial interface between the surfaces 242 and 212) and lessens to a range of about 0.8 mm to about 1.0 mm at the narrowest spacing (e.g., near the output end 204). In such a case, the gap spacing in the middle of the second compression section 240 may be in a range of about 2 mm to about 3 mm. It should be understood that such gap spacing dimensional parameters are merely exemplary and all dimensions of gap spacing and variations thereof are envisioned and within the scope of this disclosure.

(40) Referring also to FIG. 7, in some embodiments the machine 200 is motorized. For example, in the depicted embodiment the machine 200 includes a drive train 250 and an electric motor 252. In some embodiments, the motor 252 is a variable speed DC motor, and may be a gear motor. The drive train 250 transmits the rotary motion of the motor 252 to various driven portions of the machine 200, such as the first conveyor assembly 210, the first compression section 220, and/or the second conveyor assembly 241. In some embodiments, a quick release mechanism is included whereby the electric motor 252 can be decoupled from the drive train 250 for cleaning or the use of manual power input. For the use of manual power input, in some embodiments a manual hand crank input shaft 260 (refer to FIG. 5) can be used to manually power various driven portions of the machine 200, such as the first conveyor assembly 210, the first compression section 220, and/or the second conveyor assembly 241.

(41) Referring also to FIG. 8, in some embodiments the machine 200 includes a hinge mechanism 270 that allows the machine 200 to be at least partially opened for cleaning and/or maintenance. For example, in the depicted embodiment the hinge mechanism 270 is arranged to allow the second conveyor assembly 241 to be pivoted away from the first conveyor assembly 210. The drive train 250 is also conveniently configured to allow the second conveyor assembly 241 to be pivoted away from the first conveyor assembly 210 without requiring manual dismantling of the drive train 250.

(42) In some embodiments, a receptacle 280 is included near the output end 204. Such a receptacle 280 can be used to catch materials such as the material of the mold member in some cases. In some embodiments, the receptacle 280 is configured as a sink and can collect water used for cleaning the machine 200. In some embodiments, also near the output end 204 is a tray 290 that can receive post-processed arrangement materials.

(43) In some embodiments, one or more stationary brushes, portable brushes, and/or a combination thereof can be included that clean the conveyor surfaces 212 and/or 242 as the conveyor surfaces 212 and/or 242 pass by the brushes. In certain embodiments, cloths, abrasive pads, and/or other types of cleaning means can be included that clean the conveyor surfaces 212 and/or 242 as the conveyor surfaces 212 and/or 242 pass by.

(44) In some embodiments, mechanisms are included for adjusting the tram of the conveyor rollers and/or adjusting the tension of the conveyor belts. For example, the first conveyor assembly 210 can include adjustment mechanisms 214a and 214b. Additionally, the second conveyor assembly 241 can include adjustment mechanisms 244a and 244b. Any additional conveyers may include additional adjustment mechanisms. Such adjustment mechanisms 214a-b and 244a-b can be manipulated to fine tune the positioning and orientation of the end conveyor rollers of the first conveyor assembly 210 and the second conveyor assembly 241 respectively.

(45) In some embodiments, a third compression section is included. For example, in some embodiments a pressure plate is rammed against the mostly empty dip-molded article after processing the article through the second compression section 240. Such a third compression can expel a little more material of the mold member out of the dip-molded article. In some embodiments, the third compression section may be operated manually. In some embodiments, the third compression section may be operated automatically or by a motor.

(46) In some embodiments, a hood (not shown) can be used to at least partially enclose the machine 200. The hood can enhance safe operations of the machine 200. In some embodiments, the hood is movable (e.g., pivotable) away from the machine 200 and a safety interlock switch is included to detect whether the hood is properly positioned. Hence, when the hood is moved away from the machine 200, the machine 200 is prevented from operating in some embodiments.

(47) While the inventive concepts provided herein are described in the context of the manufacturing process of an inflatable medical implant, it should be understood that the inventive concepts are by no means limited to such a context. In fact, the inventive concepts can be applied for the manufacturing processes of many other dip-molded medical devices and for the manufacturing processes of non-medical devices that are dip-molded or manufactured in a method containing a mold and an external article, which may not be by dipping.

(48) Throughout this disclosure, a numerical value of a parameter, feature, characteristic, object, or dimension, may be stated or described in terms of a numerical range format. Such a numerical range format, as used herein, illustrates implementation of some exemplary embodiments of the invention, and does not inflexibly limit the scope of the exemplary embodiments of the invention. Accordingly, a stated or described numerical range also refers to, and encompasses, all possible sub-ranges and individual numerical values (where a numerical value may be expressed as a whole, integral, or fractional number) within that stated or described numerical range. For example, a stated or described numerical range ‘from 1 to 6’ also refers to, and encompasses, all possible sub-ranges, such as ‘from 1 to 3’, ‘from 1 to 4’, ‘from 1 to 5’, ‘from 2 to 4’, ‘from 2 to 6’, ‘from 3 to 6’, etc., and individual numerical values, such as ‘1’, ‘1.3’, ‘2’, ‘2.8’, ‘3’, ‘3.5’, ‘4’, ‘4.6’, ‘5’, ‘5.2’, and ‘6’, within the stated or described numerical range of ‘from 1 to 6’. This applies regardless of the numerical breadth, extent, or size, of the stated or described numerical range.

(49) Moreover, for stating or describing a numerical range, the phrase ‘in a range of between about a first numerical value and about a second numerical value’, is considered equivalent to, and meaning the same as, the phrase ‘in a range of from about a first numerical value to about a second numerical value’, and, thus, the two equivalently meaning phrases may be used interchangeably.

(50) The term ‘about’, as used herein, refers to ±10% of the stated numerical value.

(51) It is to be fully understood that certain aspects, characteristics, and features, of the invention, which are, for clarity, illustratively described and presented in the context or format of a plurality of separate embodiments, may also be illustratively described and presented in any suitable combination or sub-combination in the context or format of a single embodiment. Conversely, various aspects, characteristics, and features, of the invention which are illustratively described and presented in combination or sub-combination in the context or format of a single embodiment, may also be illustratively described and presented in the context or format of a plurality of separate embodiments.

(52) Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.

(53) While this specification contains many specific implementation details, these should not be construed as limitations on the scope of any invention or of what may be claimed, but rather as descriptions of features that may be specific to particular embodiments of particular inventions. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Moreover, although features may be described herein as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

(54) Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system modules and components in the embodiments described herein should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single product or packaged into multiple products.

(55) Particular embodiments of the subject matter have been described. Other embodiments are within the scope of the following claims. For example, the actions recited in the claims can be performed in a different order and still achieve desirable results. As one example, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results.