阅读说明：本技术 一种集装箱角件后处理工艺 (Container corner fitting post-treatment process ) 是由 常万明 郑文钦 于 2021-09-14 设计创作，主要内容包括：本发明公开了一种集装箱角件后处理工艺,属于角件后处理技术领域,采用不同抛丸机进行角件的清理,使的角件表面得到有效的清理,便于浸漆；采用积放悬链冷却输送,可以对角件进行冷却,且当后续设备故障时启动缓存系统,吊钩绕过后续设备直接导落砂机处接件,减少整个车间停机时间；采用内腔清洗装置,通过内腔清理装置针对角件内腔进行初步清理后,可以缩短后续连续履带抛丸清理机每批次的作业时间,提高整个工艺效率；采用连续履带抛丸清理机,角件容易翻身,且连续翻身,且可以对角件内部清理的特别干净。(The invention discloses a post-treatment process of container corner fittings, which belongs to the technical field of corner fitting post-treatment, wherein different shot blasting machines are adopted to clean the corner fittings, so that the surfaces of the corner fittings are effectively cleaned, and the paint dipping is convenient; the corner fittings can be cooled by adopting power and free suspension chain cooling conveying, and when the follow-up equipment fails, the cache system is started, and the lifting hook bypasses the follow-up equipment to directly guide the shakeout machine for connection, so that the downtime of the whole workshop is reduced; by adopting the inner cavity cleaning device, after the inner cavity of the corner fitting is preliminarily cleaned by the inner cavity cleaning device, the operation time of each batch of the subsequent continuous track shot blasting machine can be shortened, and the whole process efficiency is improved; by adopting the continuous track shot blasting machine, the corner fittings are easy to turn over and can be continuously turned over, and the inside of the corner fittings can be cleaned particularly cleanly.)

1. The post-treatment process of the container corner fittings is characterized by comprising the following steps:

s1, cooling and conveying the power and free suspension chain: taking out the corner fittings (1) from the shakeout machine through a manipulator, and placing the corner fittings on a lifting appliance rotating frame on a stacking chain for cooling and caching;

s2, primary shot blasting (rough blasting): sending the corner fittings into a power and free catenary shot blasting machine through a power and free catenary for shot blasting cleaning;

s3, casting head separation: the roughly-polished corner fittings are taken down from the lifting appliance rotating frame through a manipulator and sent to a dead head cutting device (2) to cut off dead heads;

s4, cleaning an inner cavity: after the casting head of the corner fitting (1) is cut off, the corner fitting is moved to an inner cavity cleaning device (3), and the inner cavity of the corner fitting (1) is subjected to shot blasting;

s5, secondary shot blasting (fine blasting): the outer surface of the corner fitting (1) can be subjected to shot blasting treatment through a continuous crawler belt shot blasting machine, so that the trace of the casting head is removed, and the inner cavity is further cleaned;

s6, shot blasting for three times: performing shot blasting treatment on the outer surface of the corner fitting (1) by using a roller shot blasting machine to make the surface roughness uniform;

s7, dipping paint and packaging: the corner fittings (1) are conveyed by a robot pendant and a catenary, and are stacked and packaged after being subjected to dust blowing, preheating, paint dipping, paint dripping, paint throwing, paint sucking, drying, cooling and other processes;

the post-treatment process of the container corner fittings in the steps S3 and S4 is completed by the mutual cooperation of the fixed table (4), the cutting device (2) and the inner cavity cleaning device (3), wherein:

the fixed table (4) comprises a processing table (41), a moving assembly (42) and a clamping assembly (43), the moving assembly (42) is arranged at the top end of the processing table (41), the clamping assembly (43) is fixedly arranged at the top end of the moving assembly (42), the cutting device (2) is fixedly arranged at one end of the moving assembly (42), and the inner cavity cleaning device (3) is fixedly arranged at the other end of the moving assembly (42);

the corner fitting (1) clamped on the clamping assembly (43) is moved to the position of the cutting device (2) through the moving assembly (42) to perform dead head cutting, and after the cutting is completed, the corner fitting (1) is moved to the position of the inner cavity cleaning device (3) through the moving assembly (42) to perform inner cavity cleaning.

2. The container corner fitting post-treatment process according to claim 1, wherein:

the moving assembly (42) comprises a moving slide rail (421), a moving slide block (422), a moving mounting frame (423), a moving motor (424) and a moving gear (425);

remove slide rail (421) set firmly processing platform (41) top, removal slider (422) slide to be set up in removing slide rail (421), removal mounting bracket (423) set firmly remove slider (422) top, removal motor (424) set firmly in remove mounting bracket (423), removal gear (425) install in on the output of removal motor (424), it has set firmly rack (426) on removal slide rail (421) top one side, removal gear (425) with rack (426) intermeshing, clamping component (43) set firmly remove mounting bracket (423) top.

3. The container corner fitting post-treatment process according to claim 2, wherein:

the clamping assembly (43) comprises a fixed plate (431), a telescopic cylinder (432), a bearing bracket (433) and a fixed air clamp (434);

the fixed plate (431) is fixedly arranged at the top end of the movable mounting frame (423), the telescopic cylinder (432) is arranged on one side of the fixed plate (431), the output end of the telescopic cylinder (432) penetrates through the fixed plate (431) to be connected with the bearing support (433), the fixed air clamp (434) is fixedly arranged on the bearing support (433), and the corner fitting (1) is placed on the bearing support (433) and is clamped tightly through the fixed air clamp (434).

4. A container corner fitting post-treatment process according to claim 3, characterised in that:

the loading support (433) is provided with a through hole (435), a shot pipeline (436) is arranged below the inner cavity cleaning device (3), the bottom end of the processing table (41) is provided with a shot collecting device (437), and the shot collecting device (437) is communicated with the shot pipeline (436).

5. The container corner fitting post-treatment process according to claim 1, wherein:

the cutting device (2) comprises a cutting support (21), a cutting lifting cylinder (22), a cutting mounting plate (23) and a cutting machine (24);

cutting support (21) set firmly processing platform (41) top one side, cutting lift cylinder (22) set firmly cutting support (21) top, the output of cutting lift cylinder (22) runs through cutting support (21) is connected cutting mounting panel (23), cutting machine (24) set firmly cutting mounting panel (23) bottom.

6. The container corner fitting post-treatment process according to claim 5, wherein:

and a casting head collecting box (25) is arranged below the cutting machine (24).

7. The container corner fitting post-treatment process according to claim 1, wherein:

the inner cavity cleaning device (3) comprises a shot blasting support (31), a shot blasting lifting cylinder (32), a shot blasting mounting rack (33), an air cylinder (34) and a shot blasting assembly (35);

throw ball support (31) set firmly in one side of cutting device (2) is kept away from on processing platform (41) top, throw ball lifting cylinder (32) set firmly in throw ball support (31) top, the output of throwing ball lifting cylinder (32) runs through throw ball support (31) connect in throw ball mounting bracket (33), be equipped with in throwing ball mounting bracket (33) cylinder (34), the output of cylinder (34) runs through throw ball mounting bracket (33) connect in throw ball subassembly (35).

8. The container corner fitting post-treatment process of claim 7, wherein:

the shot blasting assembly (35) comprises a connecting plate (351), a rotary cylinder (352), an adjusting seat (353), an adjusting shaft (354), an adjusting motor (355), an adjusting block (356), an adjusting plate (357) and a shot blasting machine (358);

the connecting plate (351) is fixedly connected to the output end of the air cylinder (34), the rotating air cylinder (352) is installed on the connecting plate (351), the adjusting seat (353) is installed on the rotating air cylinder (352), the adjusting block (356) is installed in the adjusting seat (353) through the adjusting shaft (354), the adjusting motor (355) is arranged at the top end of the adjusting seat (353), the output end of the adjusting motor (355) is connected with the adjusting shaft (354), the adjusting plate (357) is installed on the adjusting block (356), and the shot blasting machine (358) is installed on the adjusting plate (357).

Technical Field

The invention relates to the technical field of container corner fitting post-processing, in particular to a container corner fitting post-processing technology.

Background

The corner fittings are important parts on the container, play a key role in the operations of hoisting, carrying, fixing, stacking and bolting the container, almost all transmit the most acting force received by the container body by the corner fittings, and simultaneously, as the outermost edge of the container body, the corner fittings also play a role in protecting the container body.

The corner fittings need soak the lacquer at the external surface, prevents that the corner fittings from rustting ageing, so need carry out the surface cleaning through aftertreatment technology, and the surface effect after current treatment process handles is relatively poor, soaks the lacquer back, and the corner fittings uses and drops easily after the end time, and current treatment process is longer to corner fittings inner chamber cleaning time, and is inefficient.

Disclosure of Invention

In order to overcome the defects of the prior art, the technical problem to be solved by the invention is to provide a container corner fitting post-treatment process.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a post-treatment process for container corner fittings, which comprises the following specific process flows:

s1, cooling and conveying the power and free suspension chain: taking out the corner fittings from the shakeout machine through a manipulator, and placing the corner fittings on a lifting appliance rotating frame on a stacking chain for cooling and caching;

s2, primary shot blasting (rough blasting): sending the corner fittings into a power and free catenary shot blasting machine through a power and free catenary for shot blasting cleaning;

s3, casting head separation: taking off the roughly-polished corner fittings from the lifting appliance rotating frame through a manipulator, and sending the corner fittings to a dead head cutting device to cut off a dead head;

s4, cleaning an inner cavity: after the casting head of the corner fitting is cut off, the corner fitting is moved to an inner cavity cleaning device, and the inner cavity of the corner fitting is subjected to shot blasting;

s5, secondary shot blasting (fine blasting): shot blasting treatment can be carried out on the outer surface of the corner fitting through the continuous crawler belt shot blasting machine, the trace of the casting head is removed, and the inner cavity is further cleaned;

s6, shot blasting for three times: performing shot blasting treatment on the outer surface of the corner fitting through a roller shot blasting machine to ensure that the surface roughness is uniform;

s7, dipping paint and packaging: the corner fittings are conveyed by a robot pendant and a catenary, and are subjected to dust blowing, preheating, paint dipping, paint dripping, paint throwing, paint absorption, drying, cooling and other processes, and then are stacked and packaged;

the post-treatment process of the container corner fittings in the steps S3 and S4 is completed by the mutual cooperation of the fixed table, the cutting device and the cavity cleaning device, wherein: the fixed table comprises a processing table, a moving assembly and a clamping assembly, the moving assembly is arranged at the top end of the processing table, the clamping assembly is fixedly arranged at the top end of the moving assembly, the cutting device is fixedly arranged at one end of the moving assembly, and the inner cavity cleaning device is fixedly arranged at the other end of the moving assembly; the corner fitting clamped on the clamping assembly is moved to the position of the cutting device through the moving assembly to perform casting head cutting, and after the cutting is completed, the corner fitting is moved to the position of the inner cavity cleaning device through the moving assembly to perform inner cavity cleaning.

The invention has the preferable technical scheme that the moving assembly comprises a moving slide rail, a moving slide block, a moving installation frame, a moving motor and a moving gear; the movable slide rail sets firmly processing platform top, the movable sliding block slides and sets up in the movable slide rail, the movable mounting bracket sets firmly the movable sliding block top, the traveling motor sets firmly in the movable mounting bracket, the mobile gear install in on the traveling motor output, the gear strip has set firmly on movable slide rail top one side, the mobile gear with gear strip intermeshing, clamping component sets firmly the movable mounting bracket top.

The invention has the preferable technical scheme that the clamping assembly comprises a fixing plate, a telescopic cylinder, a bearing bracket and a fixing air clamp; the fixed plate sets firmly remove the mounting bracket top, the telescoping cylinder install in fixed plate one side, the output shaft of telescoping cylinder passes the fixed plate is connected bear the support, fixed gas clamp sets firmly on bearing the support, and the corner fittings is placed bear on the support, and press from both sides tightly through fixed gas clamp.

The invention has the preferable technical scheme that the bearing support is provided with a through hole, a shot pipeline is arranged below the inner cavity cleaning device, and the bottom end of the processing table is provided with a shot collecting device which is communicated with the shot pipeline.

The invention has the preferable technical scheme that the cutting device comprises a cutting bracket, a cutting lifting cylinder, a cutting mounting plate and a cutting machine; the cutting support sets firmly processing platform top one side, the cutting lifting cylinder sets firmly cutting support top, the output of cutting lifting cylinder runs through the cutting leg joint the cutting mounting panel, the cutting machine sets firmly cutting mounting panel bottom.

The invention has the preferable technical scheme that a casting head collecting box is arranged below the cutting machine.

The invention has the preferable technical scheme that the inner cavity cleaning device comprises a shot blasting support, a shot blasting lifting cylinder, a shot blasting mounting frame, a cylinder and a shot blasting assembly; the shot blasting support is fixedly arranged on one side, far away from the cutting device, of the top end of the machining table, the shot blasting lifting cylinder is fixedly arranged on the top end of the shot blasting support, the output end of the shot blasting lifting cylinder penetrates through the shot blasting support and is connected to the shot blasting mounting frame, the cylinder is arranged in the shot blasting mounting frame, and the output end of the cylinder penetrates through the shot blasting mounting frame and is connected to the shot blasting assembly.

The invention has the preferable technical scheme that the shot blasting assembly comprises a connecting plate, a rotary cylinder, an adjusting seat, an adjusting shaft, an adjusting motor, an adjusting block, an adjusting plate and a shot blasting machine; the connecting plate fixed connection in on the output of cylinder, revolving cylinder install in on the connecting plate, adjust the seat install in on the revolving cylinder, the regulating block passes through the regulating spindle install in adjust in the seat, accommodate motor locates adjust the seat top, just accommodate motor's output is connected the regulating spindle, the regulating plate install in on the regulating block, the shot-blasting machine install in on the regulating plate.

The invention has the beneficial effects that:

according to the container corner fitting post-treatment process provided by the invention, different shot blasting machines are adopted to clean corner fittings, so that the surfaces of the corner fittings are effectively cleaned, and the container corner fittings are convenient to dip paint.

Secondly, the container corner fitting post-treatment process provided by the invention adopts a power and free catenary chain for cooling and conveying, can cool the corner fitting, and when the follow-up equipment fails, the buffer system is started, and the lifting hook bypasses the follow-up equipment and directly leads to a shakeout machine for connecting the corner fitting, so that the downtime of the whole workshop is reduced.

Thirdly, the container corner fitting post-treatment process provided by the invention adopts the inner cavity cleaning device, and after the inner cavity of the corner fitting is preliminarily cleaned by the inner cavity cleaning device, the operation time of each batch of the subsequent continuous track shot blasting machine can be shortened, and the whole process efficiency is improved.

Fourthly, the container corner fitting post-treatment process provided by the invention adopts a continuous crawler belt shot blasting machine, so that the corner fitting is easy to turn over and can be continuously turned over, and the interior of the corner fitting can be cleaned particularly cleanly.

Drawings

FIG. 1 is a flow diagram of a container corner fitting post-treatment process provided in an embodiment of the present invention;

FIG. 2 is a schematic view of the overall structure of the cutting device and lumen cleaning device in accordance with an embodiment of the present invention;

FIG. 3 is a schematic view of the structure of A-A of the present invention;

FIG. 4 is a schematic structural view of B-B of the present invention;

FIG. 5 is a schematic structural view of section A of the present invention;

in the figure: 1. a corner fitting; 2. a cutting device; 21. cutting the stent; 22. cutting the lifting cylinder; 23. cutting the mounting plate; 24. a cutter; 25. a casting head collecting box; 3. an inner cavity cleaning device; 31. shot blasting support; 32. a shot blasting lifting cylinder; 33. shot blasting mounting rack; 34. a cylinder; 35. a shot blasting assembly; 351. a connecting plate; 352. a rotating cylinder; 353. an adjusting seat; 354. an adjustment shaft; 355. adjusting the motor; 356. an adjusting block; 357. an adjusting plate; 358. shot blasting machine; 4. a fixed table; 41. a processing table; 42. a moving assembly; 421. moving the slide rail; 422. moving the slide block; 423. moving the mounting rack; 424. a moving motor; 425. a moving gear; 426. a gear rack; 43. a clamping assembly; 431. a fixing plate; 432. a telescopic cylinder; 433. a load bearing support; 434. fixing the air clamp; 435. a through hole; 436. a projectile tube; 437. and (4) a collecting device.

Detailed Description

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

As shown in the figure, the post-treatment process of the container corner fittings provided by the invention comprises the following specific steps:

s1, cooling and conveying the power and free suspension chain: taking the corner fitting 1 out of the shakeout machine through a manipulator, and placing the corner fitting on a lifting appliance rotating frame on a stacking chain for cooling and caching;

s2, primary shot blasting (rough blasting): the corner fitting 1 is sent into a power and free catenary shot blasting machine through a power and free catenary to carry out shot blasting cleaning; the surface bonded sand can be removed.

S3, casting head separation: taking off the roughly-polished corner fitting 1 from the lifting appliance rotating frame through a manipulator, and sending the corner fitting to a dead head cutting device 2 to cut off a dead head; manual cutting is not needed, and automation of the process is realized.

S4, cleaning an inner cavity: after the casting head of the corner fitting 1 is cut off, the corner fitting is moved to an inner cavity cleaning device 3, and the inner cavity of the corner fitting 1 is subjected to shot blasting; preliminary washing is carried out to the inside of corner fitting 1 through inner chamber belt cleaning device 3, gets rid of the sand sticking and other debris of corner fitting 1 inner chamber to reduce subsequent clearance time.

S5, secondary shot blasting (fine blasting): the outer surface of the corner fitting 1 can be subjected to shot blasting treatment through the continuous crawler belt shot blasting machine, so that the trace of the casting head is removed, and the inner cavity is further cleaned.

S6, shot blasting for three times: performing shot blasting treatment on the outer surface of the corner fitting 1 by using a roller shot blasting machine to make the surface roughness uniform;

s7, dipping paint and packaging: the corner fittings 1 are conveyed by a robot pendant and a catenary, and are subjected to dust blowing, preheating, paint dipping, paint dripping, paint throwing, paint absorption, drying, cooling and other processes, and then are stacked and packaged;

the post-treatment process of the container corner fittings 1 in the above steps S3 and S4 is completed by the mutual cooperation of the fixed table 4, the cutting device 2 and the cavity cleaning device 3, wherein:

the fixed station 4 comprises a processing station 41, a moving assembly 42 and a clamping assembly 43, wherein the moving assembly 42 is arranged at the top end of the processing station 41, the clamping assembly 43 is fixedly arranged at the top end of the moving assembly 42, the cutting device 2 is fixedly arranged at one end of the moving assembly 42, and the inner cavity cleaning device 3 is fixedly arranged at the other end of the moving assembly 42; the corner fitting 1 clamped on the clamping assembly 43 is moved to the position of the cutting device 2 through the moving assembly 42 for casting head cutting, and after the casting head cutting is finished, the corner fitting 1 is moved to the position of the inner cavity cleaning device 3 through the moving assembly 42 for inner cavity cleaning. The corner fitting 1 is taken down from the lifting appliance rotating frame through the manipulator and placed on the clamping assembly 43, the corner fitting 1 is moved to the position of the cutting device 2 through the moving assembly 42 to perform casting head cutting, the corner fitting 1 is moved to the inner cavity cleaning device 3 through the moving assembly 42 after cutting is completed, and the inner cavity cleaning device 3 extends into the inner cavity of the corner fitting 1 from the mounting hole in the corner fitting 1 to perform shot blasting cleaning. The inner cavity of the corner fitting 1 is cleaned preliminarily through inner cavity cleaning, so that the bonded sand and other sundries in the inner cavity are cleaned up, and the operation time of a follow-up shot blasting machine is shortened.

Specifically, the moving assembly 42 includes a moving slide rail 421, a moving slide block 422, a moving mounting rack 423, a moving motor 424 and a moving gear 425; the movable slide rail 421 is fixedly arranged at the top end of the processing table 41, the movable slide block 422 is slidably arranged in the movable slide rail 421, the movable mounting frame 423 is fixedly arranged at the top end of the movable slide block 422, the movable motor 424 is fixedly arranged in the movable mounting frame 423, the movable gear 425 is arranged at the output end of the movable motor 424, a gear strip 426 is fixedly arranged on one side of the top end of the movable slide rail 421, the movable gear 425 and the gear strip 426 are meshed with each other, and the clamping assembly 43 is fixedly arranged at the top end of the movable mounting frame 423. The output shaft of the moving motor 424 drives the moving gear 425 to rotate, the moving gear 425 and the gear bar 426 are matched with each other, the moving sliding block 422 and the moving mounting rack 423 are driven to slide in the moving sliding rail 421, so that the clamping device on the moving mounting rack 423 is driven to move, the moving corner fitting 1 is driven by the moving motor 424 to be stable, and the accurate positioning can be realized.

Specifically, the clamping assembly 43 includes a fixed plate 431, a telescopic cylinder 432, a bearing bracket 433 and a fixed air clamp 434; the fixed plate 431 is fixedly arranged at the top end of the movable mounting frame 423, the telescopic cylinder 432 is arranged on one side of the fixed plate 431, an output shaft of the telescopic cylinder 432 penetrates through the fixed plate 431 to be connected with the bearing support 433, the fixed air clamp 434 is fixedly arranged on the bearing support 433, and the corner fitting 1 is placed on the bearing support 433 and clamped through the fixed air clamp 434. The corner fitting 1 is placed on a bearing bracket 433 through a mechanical arm and is clamped and fixed by a fixed air clamp 434, and the corner fitting 1 is sent to a cutting device 2 or an inner cavity cleaning device 3 through a telescopic cylinder 432.

Further, a through hole 435 is formed in the bearing support 433, a shot pipeline 436 is arranged below the inner cavity cleaning device 3, a shot collecting device 437 is arranged at the bottom end of the processing table 41, and the shot collecting device 437 is communicated with the shot pipeline 436. The corner fitting 1 is provided with three mounting holes, one of the mounting holes is downwards communicated with the through hole 435 on the bearing bracket 433, and the shot sprayed by the inner cavity cleaning device 3 falls into the shot collecting device 437 through a shot pipeline 436 from the through hole 435 for collecting the shot.

Specifically, the cutting device 2 comprises a cutting bracket 21, a cutting lifting cylinder 22, a cutting mounting plate 23 and a cutting machine 24; the cutting support 21 is fixedly arranged on one side of the top end of the processing table 41, the cutting lifting cylinder 22 is fixedly arranged on the top end of the cutting support 21, the output end of the cutting lifting cylinder 22 penetrates through the cutting support 21 to be connected with the cutting installation plate 23, and the cutting machine 24 is fixedly arranged at the bottom end of the cutting installation plate 23. The cutting machine 24 can be driven to move up and down through the cutting lifting cylinder 22, and operation and cutting are convenient.

Further, a casting head collecting box 25 is arranged below the cutting machine 24 and used for collecting the cut casting heads, so that the casting heads can be conveniently conveyed to a furnace burden storage.

Specifically, the inner cavity cleaning device 3 comprises a shot blasting support 31, a shot blasting lifting cylinder 32, a shot blasting mounting rack 33, an air cylinder 34 and a shot blasting assembly 35; shot blasting support 31 set firmly in one side of cutting device 2 is kept away from on the processing platform 41 top, shot blasting lift cylinder 32 set firmly in shot blasting support 31 top, shot blasting lift cylinder 32's output runs through shot blasting support 31 connect in shot blasting mounting bracket 33, be equipped with in shot blasting mounting bracket 33 cylinder 34, cylinder 34's output runs through shot blasting mounting bracket 33 connect in throw ball subassembly 35. The shot blasting lifting cylinder 32 is used for moving the shot blasting assembly 35 downwards to the same height of the mounting hole of the corner fitting 1, and the shot blasting assembly 35 is moved into the mounting hole of the corner fitting 1 through the air cylinder 34.

Further, the shot blasting assembly 35 comprises a connecting plate 351, a rotating cylinder 352, an adjusting seat 353, an adjusting shaft 354, an adjusting motor 355, an adjusting block 356, an adjusting plate 357 and a shot blasting machine 358; the connecting plate 351 is fixedly connected to the output end of the cylinder 34, the rotary cylinder 352 is mounted on the connecting plate 351, the adjusting seat 353 is mounted on the rotary cylinder 352, the adjusting block 356 is mounted in the adjusting seat 353 through the adjusting shaft 354, the adjusting motor 355 is disposed at the top end of the adjusting seat 353, the output end of the adjusting motor 355 is connected to the adjusting shaft 354, the adjusting plate 357 is mounted on the adjusting block 356, and the shot blasting machine 358 is mounted on the adjusting plate 357. Through the cooperation of revolving cylinder 352 and adjusting motor 355, can adjust shot-blasting machine 358's injection direction to can be to the inner wall multi-angle of corner fittings 1 inner chamber.

While the invention has been described with reference to a preferred embodiment, it will 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 spirit and scope of the invention. The present invention is not to be limited by the specific embodiments disclosed herein, and other embodiments that fall within the scope of the claims of the present application are intended to be within the scope of the present invention.