阅读说明：本技术 一种应用于无人机的精密分度盘 (Be applied to unmanned aerial vehicle's accurate graduated disk ) 是由 杨俊博 于 2019-09-18 设计创作，主要内容包括：本发明涉及分度装置制造技术领域,且公开了一种应用于无人机的精密分度盘,包括卧式底板,所述卧式底板的上端外表面固定安装有底盘,所述底盘的上端外表面固定安装有安装盘,所述安装盘的上端外表面设置有分度转盘,所述安装盘和底盘的一侧固定安装有电机,所述卧式底板的后端固定安装有立式底板,且立式底板位于底盘的后方,所述分度转盘的上端外表面固定安装有台面,所述分度转盘的下方固定安装有上刀体,所述分度转盘的内部设置有主轴。该应用于无人机的精密分度盘,能够采用立卧两个工作方式,分度时可以正反转,正反运行,分度盘设置刻度孔,设置效果更好,并且可以旋转一个工位时定位锁紧,精度更高。(The invention relates to the technical field of manufacturing of indexing devices, and discloses a precision indexing disc applied to an unmanned aerial vehicle, which comprises a horizontal bottom plate, wherein a chassis is fixedly arranged on the outer surface of the upper end of the horizontal bottom plate, an installation disc is fixedly arranged on the outer surface of the upper end of the chassis, an indexing turntable is arranged on the outer surface of the upper end of the installation disc, a motor is fixedly arranged on one side of the installation disc and one side of the chassis, a vertical bottom plate is fixedly arranged on the rear end of the horizontal bottom plate and positioned behind the chassis, a table top is fixedly arranged on the outer surface of the upper end of the indexing turntable, an upper cutter body is fixedly arranged below the indexing turntable, and a main shaft. This be applied to unmanned aerial vehicle's accurate graduated disk can adopt two working methods of crouching immediately, can just reversing during the graduation, and positive and negative operation, graduated disk set up the scale hole, set up the effect better to location locking when can rotating a station, the precision is higher.)

1. The utility model provides a be applied to unmanned aerial vehicle's precision graduated disk, includes horizontal bottom plate (1), its characterized in that: a chassis (2) is fixedly arranged on the outer surface of the upper end of the horizontal bottom plate (1), a mounting plate (3) is fixedly arranged on the outer surface of the upper end of the chassis (2), an indexing turntable (4) is arranged on the outer surface of the upper end of the mounting plate (3), a motor (5) is fixedly arranged on one side of the mounting plate (3) and one side of the chassis (2), a vertical bottom plate (6) is fixedly arranged at the rear end of the horizontal bottom plate (1), the vertical bottom plate (6) is positioned behind the chassis (2), a table board (7) is fixedly arranged on the outer surface of the upper end of the indexing turntable (4), an upper cutter body (8) is fixedly arranged below the indexing turntable (4), a main shaft (9) is arranged inside the indexing turntable (4), the bottom of the main shaft (9) penetrates through the inside of the mounting plate (3) to be rotatably connected with the chassis (2), and nuts (10), a stopping ring (11) is fixedly installed at the lower end of the nut (10), worm wheels (13) are fixedly installed on two sides of the lower end of the main shaft (9), a screw rod (14) is fixedly installed at the upper end of each worm wheel (13), the inner side of each screw rod (14) is rotatably connected with the outer surface of the main shaft (9), a signaling disc (15) is fixedly installed at the lower end of the inner portion of the indexing rotary disc (4), a signaling support (16) is fixedly installed on one side, far away from the main shaft (9), of each signaling disc (15), a large nut (18) is fixedly installed on one side, close to the motor (5), of each screw rod (14), a guide pin (17) is fixedly installed on one side, far away from the screw rod (14), of each large nut (18), a protective cover (19) is arranged between the base plate (2) and the upper cutter body (8), outer end teeth (20) are fixedly installed below the guide pins (17), and a brake rod, and a reversing device (22) is fixedly installed on one side of the screw rod (14) far away from the motor (5).

2. The precision indexing disc applied to the unmanned aerial vehicle as claimed in claim 1, wherein: mounting disc (3) are including rotating groove (31), mounting groove (32), stopper (33) and oil filler point (34), mounting groove (32) are located the inboard in rotation groove (31), the outside of mounting groove (32) is rotated with the inboard in rotation groove (31) and is connected, stopper (33) are located the upper end surface in rotation groove (31), the quantity of stopper (33) is four groups, oil filler point (34) are located the outside surface of mounting disc (3).

3. The precision indexing disc applied to the unmanned aerial vehicle according to claim 1 or 2, wherein: graduation carousel (4) are including graduation mark hole (41), snap ring (42) and locating hole (43), graduation mark hole (41) are located the upper end surface of graduation carousel (4), the quantity of graduation mark hole (41) is a plurality of groups, graduation mark hole (41) are equidistance straight line and arrange, snap ring (42) are located the lower extreme at the inside center of graduation carousel (4), the upper end surface of snap ring (42) is provided with locating hole (43), the quantity of locating hole (43) is a plurality of groups, snap ring (42) are through locating hole (43) and mounting groove (32) fixed connection of mounting disc (3).

4. The precision indexing disc applied to the unmanned aerial vehicle as claimed in claim 1, wherein: the two sides of the main shaft (9) are provided with plane bearings (12), the number of the plane bearings (12) is four, two groups of the plane bearings (12) are located at the lower end of the retaining ring (11), and the other two groups of the plane bearings (12) are located at the two sides of the lower end of the main shaft (9) and are fixedly connected with the inner portion of the lower end of the chassis (2).

5. The precision indexing disc applied to the unmanned aerial vehicle as claimed in claim 1, wherein: brake lever (21) are including hookup seat (211), motor coupling (212), worm shaft coupling (213), sealing washer (214), worm (215) and end cover (216), brake lever (21) are through hookup seat (211) and motor (5) fixed connection, motor coupling (212) and worm shaft coupling (213) fixed connection, the one end and worm (215) fixed connection of motor coupling (212) are kept away from in worm shaft coupling (213), brake lever (21) are rotated through worm (215) and are connected with main shaft (9).

6. The precision indexing disc applied to the unmanned aerial vehicle as claimed in claim 1, wherein: the reversing device (22) comprises a clutch disc (221), a clutch pin (222), a spring seat (223), a reverse leaning pin (224) and a reverse leaning disc (225), the lower end of the clutch disc (221) is fixedly connected with the upper end of a screw rod (14), the clutch pin (222) is located below the clutch disc (221), a reverse leaning groove is formed between the reverse leaning disc (225) and the screw rod (14), the reverse leaning pin (224) is arranged above the reverse leaning disc (225), and the spring seat (223) is located between the clutch pin (222) and the reverse leaning pin (224).

7. The precision indexing disc applied to the unmanned aerial vehicle as claimed in claim 1, wherein: a positioning locking device (23) is arranged between the mounting groove (32) and the rotating groove (31), and the outer surface of the upper end of the positioning locking device (23) is rotatably connected with the outer surface of the lower end of the indexing turntable (4).

8. The precision indexing disc applied to the unmanned aerial vehicle according to claim 1 or 2, wherein: location locking device (23) are including inclined plane recess (231), movable rod (232), pivot (233) and spring (234), inclined plane recess (231) are located the inboard of mounting groove (32), the lower extreme fixed connection of movable rod (232) and inclined plane recess (231), spring (234) and one side surface fixed connection of movable rod (232).

9. A precision indexing disc applied to unmanned aerial vehicles according to claim 1, 4, wherein: the output of motor (5) and the input electric connection of motor coupling (212), the output of motor coupling (212) and the input electric connection of worm coupling (213), the output of worm coupling (213) and the input electric connection of worm (215), the output of worm (215) and the input electric connection line of main shaft (9), the output of main shaft (9) and the input electric connection line of graduation carousel (4).

Technical Field

The invention relates to the technical field of manufacturing of indexing devices, in particular to a precise indexing disc applied to an unmanned aerial vehicle.

Background

The indexing disk is a machine tool accessory that holds a workpiece on a chuck or between two points and rotates, indexes and positions it. According to the transmission and indexing form, the device can be divided into a worm pair indexing disc, a dial indexing disc, a hole disc indexing disc, a groove disc indexing disc, an end-toothed disc indexing disc, an inductance indexing disc and a grating indexing disc.

The setting mode of current graduated disk is mostly the formula setting of falling for sleeping in, when using the graduated disk to the unmanned aerial vehicle field, can't process diversified accurate part, and current indexing equipment can't reverse, and technological effect is limited.

At unmanned aerial vehicle's manufacturing field, most component all are accurate component, need the very high processing equipment of precision, and the graduated disk needs user's visual observation and sets up turned angle before making work, does not have the scale on the graduated disk, and the precision of setting is not high, when equipment is rotating, if set up and not lead to the graduated disk rotation not in place can directly lead to the preparation work piece to be not conform to the standard, the emergence of this phenomenon can't be prevented to current equipment.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides the precise index plate applied to the unmanned aerial vehicle, which can adopt two working modes of vertical and horizontal, can rotate forwards and backwards during indexing, can run forwards and backwards, is provided with the scale holes, has better setting effect, can be positioned and locked when rotating a station, has higher precision, and solves the problems that the process effect is limited, diversified precise parts cannot be processed, the equipment precision is not high, and the index plate cannot rotate in place.

(II) technical scheme

In order to realize the purposes that the vertical and horizontal working modes can be adopted, the front and back rotation and the front and back operation can be realized during indexing, the indexing disc is provided with the scale holes, the setting effect is better, the positioning and locking can be realized when one station is rotated, the precision is higher, the problems that the process effect is limited, diversified precise parts cannot be processed, the equipment precision is not high, and the indexing disc is not rotated in place are solved, the invention provides the following technical scheme: : a precise dividing plate applied to an unmanned aerial vehicle comprises a horizontal bottom plate, wherein a chassis is fixedly arranged on the outer surface of the upper end of the horizontal bottom plate, a mounting plate is fixedly arranged on the outer surface of the upper end of the chassis, an dividing turntable is arranged on the outer surface of the upper end of the mounting plate, a motor is fixedly arranged on one side of the mounting plate and one side of the chassis, a vertical bottom plate is fixedly arranged at the rear end of the horizontal bottom plate and is positioned behind the chassis, a table board is fixedly arranged on the outer surface of the upper end of the dividing turntable, an upper cutter body is fixedly arranged below the dividing turntable, a main shaft is arranged in the dividing turntable, the bottom of the main shaft penetrates through the interior of the mounting plate and is rotatably connected with the chassis, nuts are fixedly arranged on two sides of the upper end of the main shaft, check rings, the upper end fixed mounting of worm wheel has the screw rod, and the inboard of screw rod is connected with the surface rotation of main shaft, indexing turntable's inside lower extreme fixed mounting has the signaling dish, one side fixed mounting that the signaling dish kept away from the main shaft has the signaling support, one side fixed mounting that the screw rod is close to the motor has big nut, one side fixed mounting that the big nut kept away from the screw rod has the uide pin, be provided with the protection casing between chassis and the last cutter body, the below fixed mounting of uide pin has outer end tooth, be provided with the brake lever between motor and the chassis, one side fixed mounting that the motor was kept away from to the screw rod has reversing arrangement.

Preferably, the mounting disc is including rotating groove, mounting groove, stopper and oil filler point, the mounting groove is located the inboard in rotation groove, the outside and the inboard in rotation groove of mounting groove rotate to be connected, the stopper is located the upper end surface in rotation groove, the quantity of stopper is four groups, the oil filler point is located the outside surface of mounting disc.

Preferably, the graduation carousel includes scale mark hole, snap ring and locating hole, the scale mark hole is located the upper end surface of graduation carousel, the quantity in scale mark hole is a plurality of groups, scale mark hole is the equidistance straight line and arranges, the snap ring is located the lower extreme at the inside center of graduation carousel, the upper end surface of snap ring is provided with the locating hole, the quantity of locating hole is a plurality of groups, the snap ring passes through the mounting groove fixed connection of locating hole and mounting disc.

Preferably, two sides of the main shaft are provided with four groups of plane bearings, two groups of plane bearings are positioned at the lower end of the retaining ring, and the other two groups of plane bearings are positioned at two sides of the lower end of the main shaft and are fixedly connected with the inner part of the lower end of the chassis.

Preferably, the brake lever includes coupling seat, motor shaft coupling, worm shaft coupling, sealing washer, worm and end cover, the brake lever passes through coupling seat and motor fixed connection, motor shaft coupling and worm shaft coupling fixed connection, the one end and the worm fixed connection of motor shaft coupling are kept away from to the worm shaft coupling, the brake lever passes through the worm and is connected with the main shaft rotation.

Preferably, the reversing device comprises a clutch disc, a clutch pin, a spring seat, a reverse leaning pin and a reverse leaning disc, the lower end of the clutch disc is fixedly connected with the upper end of the screw rod, the clutch pin is located below the clutch disc, a reverse leaning groove is arranged between the reverse leaning disc and the screw rod, the reverse leaning pin is arranged above the reverse leaning disc, and the spring seat is located between the clutch pin and the reverse leaning pin.

Preferably, a positioning locking device is arranged between the mounting groove and the rotating groove, and the outer surface of the upper end of the positioning locking device is rotatably connected with the outer surface of the lower end of the indexing turntable.

Preferably, the positioning and locking device comprises an inclined groove, a movable rod, a rotating shaft and a spring, the inclined groove is located on the inner side of the mounting groove, the movable rod is fixedly connected with the lower end of the inclined groove, and the spring is fixedly connected with the outer surface of one side of the movable rod.

Preferably, the output of motor and the input electric connection of motor coupling, the output of motor coupling and the input electric connection of worm coupling, the output of worm coupling and the input electric connection of worm, the output of worm and the input electric connection line of main shaft, the output of main shaft and the input electric connection line of graduation carousel.

(III) advantageous effects

Compared with the prior art, the invention provides a precise index plate applied to an unmanned aerial vehicle, which has the following beneficial effects:

1. this be applied to unmanned aerial vehicle's accurate graduated disk is provided with vertical bottom plate through the rear end at horizontal bottom plate, can make whole graduated disk possess two graduation modes of horizontal graduation and vertical graduation, has increased the scope of processing, and the processing form is more diversified.

2. This be applied to unmanned aerial vehicle's accurate graduated disk through setting up the reversal device, can make graduation carousel cooperation mounting disc reverse, has increased technological effect.

3. This be applied to unmanned aerial vehicle's accurate graduated disk sets up the scale mark hole through the upper end surface at the graduation carousel, and the scale mark hole sets up according to certain angle, and clear judgement and setting graduation angle when the graduation can have improved the precision when the graduation.

4. This be applied to unmanned aerial vehicle's accurate graduated disk through being provided with location locking device between the rotation groove and the mounting groove at the mounting disc, can rotate groove and the rotatory station of mounting groove when the mounting disc rotates by force, has prevented that the graduated disk from rotating not to the position and has made work piece processing be not conform to the phenomenon emergence of standard, has improved the accuracy of work piece.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a schematic view of the internal structure of the present invention;

FIG. 3 is a schematic view of the internal construction of the brake lever of the present invention;

FIG. 4 is a schematic view of the overall structure of the mounting plate of the present invention;

FIG. 5 is a schematic view of the overall structure of the index plate of the present invention;

FIG. 6 is an enlarged schematic view of the inverting apparatus of the present invention;

fig. 7 is an enlarged schematic view of the positioning and locking device of the present invention.

In the figure: 1. a horizontal bottom plate; 2. a chassis; 3. mounting a disc; 31. a rotating groove; 32. mounting grooves; 33. a limiting block; 34. an oil filler hole; 4. indexing the rotary table; 41. scale mark holes; 42. a snap ring; 43. positioning holes; 5. a motor; 6. a vertical base plate; 7. a table top; 8. an upper cutter body; 9. a main shaft; 10. a nut; 11. a backstop ring; 12. a flat bearing; 13. a worm gear; 14. a screw; 15. a message sending disk; 16. a signaling support; 17. a guide pin; 18. a large nut; 19. a protective cover; 20. an outer end tooth; 21. a brake lever; 211. a coupling seat; 212. a motor coupling; 213. a worm coupling; 214. a seal ring; 215. a worm; 216. an end cap; 22. a reversing device; 221. a clutch plate; 222. a clutch pin; 223. a spring seat; 224. a back rest pin; 225. a reclining plate; 23. positioning the locking device; 231. a bevel groove; 232. a movable rod; 233. a rotating shaft; 234. a spring.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-7, a precision dividing plate applied to an unmanned aerial vehicle comprises a horizontal base plate 1, a chassis 2 is fixedly installed on the outer surface of the upper end of the horizontal base plate 1, a mounting plate 3 is fixedly installed on the outer surface of the upper end of the chassis 2, an dividing rotary table 4 is arranged on the outer surface of the upper end of the mounting plate 3, a motor 5 is fixedly installed on one side of the mounting plate 3 and the chassis 2, a vertical base plate 6 is fixedly installed on the rear end of the horizontal base plate 1, the vertical base plate 6 is positioned behind the chassis 2, a table 7 is fixedly installed on the outer surface of the upper end of the dividing rotary table 4, an upper cutter body 8 is fixedly installed below the dividing rotary table 4, a main shaft 9 is arranged inside the dividing rotary table 4, the bottom of the main shaft 9 penetrates through the inside of the mounting plate 3 to be rotatably connected with the chassis 2, nuts 10 are fixedly installed on two sides of, the upper end fixed mounting of worm wheel 13 has screw rod 14, and the inboard of screw rod 14 is connected with the surface rotation of main shaft 9, indexing turntable 4's inside lower extreme fixed mounting has signalling dish 15, one side fixed mounting that signalling dish 15 kept away from main shaft 9 has signalling support 16, one side fixed mounting that screw rod 14 is close to motor 5 has big nut 18, one side fixed mounting that big nut 18 kept away from screw rod 14 has guide pin 17, be provided with protection casing 19 between chassis 2 and the last cutter body 8, the below fixed mounting of guide pin 17 has outer end tooth 20, be provided with brake lever 21 between motor 5 and the chassis 2, one side fixed mounting that screw rod 14 kept away from motor 5 has reversing device 22.

The mounting disc 3 comprises a rotating groove 31, mounting grooves 32, limiting blocks 33 and oil filling holes 34, wherein the mounting grooves 32 are located on the inner side of the rotating groove 31, the outer side of the mounting grooves 32 is rotatably connected with the inner side of the rotating groove 31, the limiting blocks 33 are located on the outer surface of the upper end of the rotating groove 31, the number of the limiting blocks 33 is four, and the oil filling holes 34 are located on the outer surface of the outer side of the mounting disc 3; the indexing turntable 4 comprises indexing dial holes 41, clamping rings 42 and positioning holes 43, the indexing dial holes 41 are positioned on the outer surface of the upper end of the indexing turntable 4, the number of the indexing dial holes 41 is a plurality of groups, the indexing dial holes 41 are linearly arranged at equal intervals, the clamping rings 42 are positioned at the lower end of the inner center of the indexing turntable 4, the positioning holes 43 are arranged on the outer surface of the upper end of the clamping rings 42, the number of the positioning holes 43 is a plurality of groups, and the clamping rings 42 are fixedly connected with the mounting grooves 32 of the mounting disc 3 through the positioning holes 43; two sides of the main shaft 9 are provided with plane bearings 12, the number of the plane bearings 12 is four, two groups of the plane bearings 12 are positioned at the lower end of the retaining ring 11, and the other two groups of the plane bearings 12 are positioned at two sides of the lower end of the main shaft 9 and are fixedly connected with the inner part of the lower end of the chassis 2; the brake lever 21 comprises a coupling seat 211, a motor coupler 212, a worm coupler 213, a sealing ring 214, a worm 215 and an end cover 216, the brake lever 21 is fixedly connected with the motor 5 through the coupling seat 211, the motor coupler 212 is fixedly connected with the worm coupler 213, one end of the worm coupler 213, which is far away from the motor coupler 212, is fixedly connected with the worm 215, and the brake lever 21 is rotatably connected with the spindle 9 through the worm 215; the reversing device 22 comprises a clutch disc 221, a clutch pin 222, a spring seat 223, a reverse leaning pin 224 and a reverse leaning disc 225, the lower end of the clutch disc 221 is fixedly connected with the upper end of the screw rod 14, the clutch pin 222 is positioned below the clutch disc 221, a reverse leaning groove is arranged between the reverse leaning disc 225 and the screw rod 14, the reverse leaning pin 224 is arranged above the reverse leaning disc 225, and the spring seat 223 is positioned between the clutch pin 222 and the reverse leaning pin 224; a positioning locking device 23 is arranged between the mounting groove 32 and the rotating groove 31, and the outer surface of the upper end of the positioning locking device 23 is rotationally connected with the outer surface of the lower end of the indexing turntable 4; the positioning and locking device 23 comprises an inclined groove 231, a movable rod 232, a rotating shaft 233 and a spring 234, wherein the inclined groove 231 is positioned at the inner side of the mounting groove 32, the movable rod 232 is fixedly connected with the lower end of the inclined groove 231, and the spring 234 is fixedly connected with the outer surface of one side of the movable rod 232; the output end of the motor 5 is electrically connected with the input end of the motor coupler 212, the output end of the motor coupler 212 is electrically connected with the input end of the worm coupler 213, the output end of the worm coupler 213 is electrically connected with the input end of the worm 215, the output end of the worm 215 is electrically connected with the input end of the main shaft 9, and the output end of the main shaft 9 is electrically connected with the input end of the indexing turntable 4.

Before the use, a user can enable the whole equipment to be flatly laid on an operation platform for disc separation operation by arranging the horizontal bottom plate 1, the equipment can be vertically arranged on the operation platform for disc separation operation by arranging the vertical bottom plate 6, before the equipment is used, lubricating oil is added into the installation disc 3 by arranging the oil injection hole 34 to prevent the equipment from being worn in a rotating way, the indexing rotary disc 4 is arranged on the installation groove 32 by arranging the positioning hole 43, the motor 5 is arranged to enable the equipment to be in a working state, the upper cutter body 8 sends a tool changing signal to control the motor 5 to act, the motor 5 rotates forwards, the motor coupling 212 and the worm coupling 213 drive the worm 215, the worm 215 drives the worm wheel 13, the worm wheel 13 drives the screw 14 to rotate, the nut 10 starts to ascend, the screw 14 drives the clutch disc 221 to rotate, the clutch pin 222 slides on the plane of the clutch disc 221, and when the nut 10, the outer end teeth 20 are disengaged, the clutch pin 222 enters the clutch disc 221, at this time, the screw 14 drives the clutch disc 221, the clutch disc 221 drives the clutch pin 222, the table surface 7 and the anti-leaning pin 224 to start indexing, the anti-leaning pin 224 climbs out of the anti-leaning disc 225, namely, the indexing turntable 4 starts tool changing action, when the indexing turntable 4 rotates to a required tool position, in order to prevent the indexing from not rotating in place, by arranging the positioning and locking device 23, the movable rod 232 rotates in the inclined plane groove 231 by the rotating shaft 233, the spring 234 can push the movable rod 232 to enter the inclined plane groove 231, if the indexing does not rotate in place, the inclined plane groove 231 is not matched with the position of the movable rod 232, the spring 234 contracts to forcibly push the movable rod 232, the installation groove 32 continues to rotate, until the inclined plane groove 231 on the installation groove 32 moves to the position of the movable rod 232 for positioning and locking, after the tool position is rotated, the, The clutch pin 222, the anti-leaning pin 224 and the upper cutter body 8 are reversed, when the anti-leaning pin 224 moves on the plane of the anti-leaning disc 225 and passes through the anti-leaning groove, the anti-leaning pin 224 is bounced into the anti-leaning groove by the spring seat 223, the anti-leaning pin 224 enters the anti-leaning groove, the right-angle surface of the anti-leaning pin 224 and the right-angle surface of the anti-leaning groove are mutually propped, the cutter frame completes coarse positioning, the rotation of the anti-leaning pin 224, the clutch pin 222 and the table board 7 is prevented, at the moment, the clutch disc 221 continues to be reversed under the driving of the screw 14, the clutch pin 222 climbs out of the clutch disc 221, the nut 10 begins to descend until the outer end teeth 20 are completely meshed, fine positioning is completed, the cutter frame is locked, the motor 5 stops rotating, the machining process begins, the indexing rotating angle can be clearly judged and set through the scale mark hole 41, and the sealing ring 214 is arranged.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.