Detailed Description
In order that the invention may be readily understood, a more complete description of the invention will be rendered by reference to the appended drawings. The drawings illustrate preferred embodiments of the invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
It will be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.
An automated assembly apparatus comprising: a housing delivery device 31 (shown in fig. 3), a pin jack device 32 (shown in fig. 7).
The shell conveying device 31 is mainly used for feeding and transporting the shell 20, so that the shell 20 can reach a designated position, and the pin plugging device 32 is matched, so that the pin plugging device 32 can accurately plug the pin 11 into the plugging hole 21 of the shell 20.
The pin plugging device 32 is mainly used for cutting out each pin 11 in the material tape 10, and is matched with the shell conveying device 31 to accurately plug the cut-out pins 11 into the plugging holes 21 of the shell 20.
The following mainly describes the specific structure of the housing conveying device 31 and the connection relation of the respective members:
As shown in fig. 3, the housing conveyance device 31 includes: a housing feeding vibration plate (not shown), a housing separating mechanism 100 and a housing conveying mechanism 200.
As shown in fig. 4, the output end of the housing feeding vibration plate is provided with a housing feeding rail 41, and the housing feeding rail 41 has a housing feeding passage 42. In this embodiment, the housing feeding channel 41 is a linear channel.
As shown in fig. 4, the case cut-off mechanism 100 includes: the case separation base 110, the case separation driving part 120, and the case separation lever 130. The shell cutting base 110 is provided with a shell feeding longitudinal channel 111 and a shell cutting transverse channel 112, and the shell feeding longitudinal channel 111 and the shell cutting transverse channel 112 are crisscrossed and mutually communicated; the shell feeding longitudinal channel 111 is communicated with the shell feeding channel 42; the housing disconnecting lever 130 is slidably disposed in the housing disconnecting lateral passage 112, and the housing disconnecting driving portion 120 is in driving connection with the housing disconnecting lever 130. In this embodiment, the housing-separating driving portion 120 is a cylinder driving structure, the housing-feeding longitudinal channel 111 is a linear channel, and the housing-separating transverse channel 112 is a linear channel.
As shown in fig. 3, the housing conveyance mechanism 200 includes: a housing transfer rail 210, a housing push assembly 220, and a housing positioning assembly 230. In particular, in the present embodiment, the number of the pin plugging devices 32 is plural, and the plural pin plugging devices 32 are sequentially arranged at intervals along the extension line direction of the housing conveying rail 210.
The casing conveying rail 210 is provided with a casing conveying channel 211 (as shown in fig. 5), and the casing conveying channel 211 is communicated with the casing separation transverse channel 112; one end of the housing disconnecting lever 130 is provided with a housing disconnecting claw 131 (as shown in fig. 6), the housing disconnecting claw 131 is provided with a disconnecting upper clamping jaw 132 and a disconnecting lower clamping jaw 133, and the disconnecting upper clamping jaw 132 and the disconnecting lower clamping jaw 133 are spaced from each other; the case cut-off driving part 120 drives the case cut-off lever 130 to reciprocate so that the case cut-off claw 131 reciprocates between the case cut-off lateral passage 112 and the case conveying passage 211. In the present embodiment, the housing conveyance path 211 is a linear path.
As shown in fig. 4, the housing push assembly 220 includes: a housing push driving part 221, a housing push rod 222, and a housing push block 223 (shown in fig. 6). The casing pushing rod 222 is slidably disposed in the casing conveying channel 211, the casing pushing block 223 is rotatably disposed on the casing pushing rod 222 through a torsion spring (not shown), the casing pushing rod 222 is provided with an avoidance groove 224 (as shown in fig. 6), and the casing pushing block 223 is accommodated in the avoidance groove 224 or is exposed out of the avoidance groove 224; the shell pushing block 223 has a wedge-shaped block structure, and the shell pushing block 223 has a shell pushing surface 225 and an avoiding sliding surface 226 (as shown in fig. 6); the housing push driving unit 221 is in driving connection with the housing push lever 222. In this embodiment, the housing pushing driving portion 221 is of a cylinder driving structure, the number of housing pushing blocks 223 is plural, the housing pushing rod 222 is provided with plural avoiding grooves 224, and the plural housing pushing blocks 223 are in one-to-one correspondence with the plural avoiding grooves 224.
As shown in fig. 3, the housing positioning assembly 230 includes: a housing positioning driving part 231 and a housing positioning plate 232; the housing positioning plate 232 is provided with a housing positioning claw 233, and the housing positioning driving part 231 is in driving connection with the housing positioning plate 232, and the housing positioning driving part 231 drives the housing positioning plate 232 so that the housing positioning claw 233 is inserted into the housing conveying passage 211 or separated from the housing conveying passage 211. In this embodiment, the housing positioning driving part 231 is a cylinder driving structure, and the housing positioning plate 232 is provided with a plurality of housing positioning claws 233, and the plurality of housing positioning claws 233 are sequentially arranged at intervals in a straight line along the extending direction of the housing conveying path 211.
Next, the operation principle of the above-described case transfer device 31 will be described:
The shell feeding vibration disc is internally provided with a plurality of shells 20, under the action of the shell feeding vibration disc, the shells 20 reach the shell feeding channels 42 of the shell feeding tracks 41 from the output ends of the shell feeding vibration disc, the shells 20 enter the shell feeding longitudinal channels 111 through the shell feeding channels 42, and the shells 20 reach the junction of the shell feeding longitudinal channels 111 and the shell cutting transverse channels 112 from the shell feeding longitudinal channels 111;
At this time, the shell cutting claw 131 on the shell cutting rod 130 is just at the junction of the shell feeding longitudinal channel 111 and the shell cutting transverse channel 112, so that the shell 20 can enter the shell cutting claw 131, and the shell 20 is clamped between the cutting upper clamping jaw 132 and the cutting lower clamping jaw 133;
the shell cutting driving part 120 drives the shell cutting rod 130, the shell cutting rod 130 drives the shell cutting claw 131, and the shell cutting claw 131 drives the shell 20 to enter the shell conveying channel 211 from the shell cutting transverse channel 112;
When the housing 20 reaches the housing conveying passage 211, the housing push driving part 221 drives the housing push rod 222 to extend forward, and the housing push rod 222 simultaneously drives the housing push block 223, at this time, the housing push surface 225 of the housing push block 223 contacts with the housing 20, so that the housing 20 in the housing separating claw 131 is separated and conveyed to a designated position; when the shell 20 in the shell cutting claw 131 is cut off, the shell cutting driving part 120 drives the shell cutting rod 130 in the opposite direction, so that the shell cutting claw 131 is reset and is ready for feeding of the next shell 20;
When the housing 20 is conveyed to a designated position, the housing positioning assembly 230 operates, and in particular, the housing positioning driving part 231 drives the housing positioning plate 232 such that the housing positioning claws 233 are inserted into the housing conveying passage 211, thereby holding the housing 20 in the housing conveying passage 211;
After the housing 20 in the housing conveying channel 211 is clamped, on one hand, the pin plugging device 32 can accurately and stably plug the pins 11 into the plugging holes 21 of the housing 20; on the other hand, the shell pushing driving part 221 drives the shell pushing rod 222 to retract backwards, and the shell pushing rod 222 drives the shell pushing block 223 at the same time, at this time, the avoiding sliding surface 226 of the shell pushing block 223 contacts with the shell 20, and as the shell 20 is fixed, the avoiding sliding surface 226 slides along the surface of the shell 20, and under the cooperation of the torsion spring, the shell pushing block 223 is gradually accommodated in the avoiding groove 224, so that the shell pushing rod 222 can retract smoothly;
When the avoiding sliding surface 226 of the housing pushing block 223 is separated from the contact with the housing 20, the housing pushing block 223 is exposed out of the avoiding groove 224 again under the action of the torsion spring, so that the next housing 20 is ready for conveying.
Next, the structural design principle of the above-described case conveying device 31 will be described:
1. The shell feeding longitudinal channels 111 and the shell cutting transverse channels 112 are crisscrossed and mutually communicated, and the shell cutting claws 131 are positioned at the junction of the two channels, so that the shell 20 can enter the shell cutting claws 131 through the shell feeding longitudinal channels 111, and the shell cutting claws 131 feed the shell 20 from the shell cutting transverse channels 112 into the shell conveying channels 211, so that the feeding operation of the shell 20 is realized; furthermore, as the shell 20 moves in the channel, the shell 20 can be accurately transferred to the designated position, and accurate feeding is realized;
2. The shell cutting claw 131 is provided with an upper cutting claw 132 and a lower cutting claw 133, and the upper cutting claw 132 and the lower cutting claw 133 are mutually spaced, so that on one hand, the upper cutting claw 132 and the lower cutting claw 133 can elastically clamp the shell 20, so that the shell 20 is more stable in the feeding process; on the other hand, when the housing cutting claw 131 reaches the housing conveying passage 211, since a space is formed between the cutting upper clamping claw 132 and the cutting lower clamping claw 133, the housing pushing block 223 can be well matched, and the housing pushing block 223 can pass through the space between the cutting upper clamping claw 132 and the cutting lower clamping claw 133 to smoothly cut the housing 20 therefrom;
3. The shell pushing block 223 is rotationally arranged on the shell pushing rod 222 through a torsion spring, the shell pushing rod 222 is provided with an avoidance groove 224, the shell pushing block 223 can be contained in the avoidance groove 224 or exposed out of the avoidance groove 224, and the shell pushing block 223 is provided with a shell pushing surface 225 and an avoidance sliding surface 226, so that on one hand, when the shell 20 is pushed, the shell pushing surface 225 is contacted with the shell; on the other hand, when the housing push block 223 is reset, the avoidance sliding surface 226 contacts with the housing and is accommodated in the avoidance groove 224 in cooperation with the torsion spring; it can be seen that the housing push rod 222 can achieve the purpose of conveying the housing 20 only by performing simple telescopic movement;
4. When the housing 20 is conveyed to a designated position, the housing positioning driving part 231 drives the housing positioning plate 232 such that the housing positioning claws 233 are inserted into the housing conveying passage 211, thereby holding the housing 20 in the housing conveying passage 211, by providing the housing positioning assembly 230, it is possible to have the following two effects: on the one hand, the pin plugging device 32 can accurately and stably plug the pin 11 into the plugging hole 21 of the shell 20; on the other hand, the housing push driving part 221 drives the housing push rod 222 to retract backwards, and the housing push rod 222 drives the housing push block 223 at the same time, at this time, the avoidance sliding surface 226 of the housing push block 223 contacts with the housing 20, and because the housing 20 is fixed, the avoidance sliding surface 226 slides along the surface of the housing 20, and under the cooperation of the torsion spring, the housing push block 223 can be gradually accommodated in the avoidance groove 224, so that the housing push rod 222 can retract smoothly.
The following mainly describes the specific structure of the pin plug device 32 and the connection relation of the respective components:
As shown in fig. 7, the pin plugging device 32 includes: the material belt transmission mechanism 33 and the pin cutting and inserting mechanism 34.
As shown in fig. 8, the tape transport mechanism 33 includes: a tape conveying rail 310, a tape conveying roller 320, and a tape conveying driving part 330. The material belt conveying track 310 is provided with a material belt conveying channel 311 (as shown in fig. 9), the material belt conveying channel 311 extends along the vertical direction, and the material belt conveying channel 311 is provided with a material belt feeding end 311a and a material belt discharging end 311b; the material belt conveying track 310 is further provided with a through hole 312 (as shown in fig. 8) which is communicated with the material belt conveying channel 311, the material belt conveying roller 320 is arranged in the material belt conveying channel 311 in a penetrating way, a material belt conveying convex block 321 (as shown in fig. 9) is arranged on the wheel surface of the material belt conveying roller 320, and the material belt conveying driving part 330 is in driving connection with the material belt conveying roller 320. In this embodiment, the belt conveying driving portion 330 is a motor driving structure, the number of belt conveying protrusions 321 is plural, the plurality of belt conveying protrusions 321 are distributed in an annular array with the rotation axis of the belt conveying roller 320 as the center, and the belt conveying channel 311 is a linear channel.
As shown in fig. 10 and 11, the pin-off plugging mechanism 34 includes: a fixed base 400, a plug sliding seat 500, a plug moving rod 600, a plug driving part 700, a cut-off main body member 800, and a cut-off auxiliary member 900. In this embodiment, the socket driving part 700 is a cylinder driving structure.
The plugging sliding seat 500 is horizontally and transversely slidably arranged on the fixed base 400, the plugging moving rod 600 is arranged on the plugging sliding seat 500, the plugging driving part 700 is in driving connection with the plugging moving rod 600, and the plugging driving part 700 drives the plugging moving rod 600 so that the plugging sliding seat 500 horizontally and transversely slides on the fixed base 400 in a reciprocating manner.
As shown in fig. 12 and 13, the cut-away body member 800 includes: a body slide bar 810, a pin-off plate 820, a pin-off guide block 830, and a pin-off guide wheel 840. The main body sliding rod 810 is slidably disposed on the socket sliding seat 500 along the horizontal and longitudinal directions, and the pin cutting board 820 and the pin cutting guide block 830 are fixed on the main body sliding rod 810; the lead cutting guide block 830 has a lead cutting guide surface 831, and the lead cutting guide wheel 840 is mounted on the fixed base 400, with the tread of the lead cutting guide wheel 840 abutting against the lead cutting guide surface 831. In the present embodiment, the lead-off guide surface 831 is a curved surface with a high-low profile.
As shown in fig. 12 and 13, the separation auxiliary 900 includes: auxiliary slide bar 910, pin-off holding block 920, pin-off guide wheel 930, and intermediate connection bar 940. The auxiliary sliding rod 910 is arranged on the plugging sliding seat 500 in a sliding manner along the horizontal and longitudinal direction, the pin cutting and pressing block 920 is fixed on the auxiliary sliding rod 910, a pin cutting and holding groove 821 connected with the material belt discharging end 311b of the material belt conveying channel 311 is formed in the pin cutting plate 820, a cutting and pressing hole 822 is formed in the groove wall of the pin cutting and holding groove 821, a cutting and pressing pin 921 is arranged on the pin cutting and pressing block 920, the pin cutting and pressing block 920 is propped against or separated from the groove wall of the pin cutting and holding groove 821, and the cutting and pressing pin 921 is contained in the cutting and pressing hole 822 or separated from the cutting and pressing hole 822.
As shown in fig. 13, the plugging moving rod 600 is provided with a cutting auxiliary guide groove 610, a pin cutting guide wheel 930 is slidingly accommodated in the cutting auxiliary guide groove 610, one end of a middle connecting rod 940 is connected with the pin cutting guide wheel 930, and the other end of the middle connecting rod 940 is connected with the auxiliary sliding rod 910. In the present embodiment, the separation auxiliary guide groove 610 extends in a curved manner along a horizontal plane.
Next, the operation principle of the pin plugging device 32 will be described:
Placing the material belt 10 in the material belt transmission channel 311 on the material belt transmission track 310, wherein the material belt transmission convex block 321 on the material belt transmission roller 320 is inserted into the through hole 14 of one pin 11 in the material belt 10; it should be noted that, the board surface of each pin 11 in the tape 10 is attached to the tape conveying channel 311, and when the pins 11 are cut off subsequently, the pins 11 are cut off along the direction perpendicular to the board surface of the pins 11, so that the pins 11 can be cut off quickly and effectively;
The material belt transmission driving part 330 drives the material belt transmission roller 320 to rotate, and the material belt transmission roller 320 in rotation drives the material belt 10 to be transmitted along the material belt transmission track 310 under the cooperation of the material belt transmission convex block 321 and the through hole 14, so that the continuous uninterrupted material belt 10 enters from the material belt feeding end 311a of the material belt transmission channel 311 and then exits from the material belt discharging end 311b of the material belt transmission channel 311;
the pins 11 coming out of the tape discharging end 311b enter the pin cutting-out accommodating groove 821 of the pin cutting-out plate 820;
after the pin 11 enters the pin-out receiving groove 821, the plugging driving part 700 drives the plugging moving lever 600 to extend, and here, the movement of the plugging moving lever 600 is divided into three stages:
In the first stage of movement of the plugging movement rod 600, the pin-cutting guide wheel 930 slides along the cutting auxiliary guide groove 610, the sliding pin-cutting guide wheel 930 pushes the auxiliary sliding rod 910 to slide horizontally and longitudinally through the intermediate connecting rod 940, the auxiliary sliding rod 910 drives the pin-cutting pressing block 920 thereon to approach the pin-cutting accommodation groove 821, so that the pin-cutting pressing block 920 can press the touching end 13 of the pin 11, and meanwhile, the cutting pressing pin 921 can pass through the through hole 14 and enter the cutting pressing hole 822;
In the second stage of the movement of the plugging movement rod 600, the plugging driving part 700 continues to drive the plugging movement rod 600 to extend, and since the auxiliary sliding rod 910 cannot continue to move, the plugging movement rod 600 drives the plugging sliding seat 500 to slide horizontally and transversely through the auxiliary sliding rod 910, and the plugging sliding seat 500 further drives the disconnecting main body member 800 and the disconnecting auxiliary member 900 to move horizontally and transversely as a whole, in the moving process, since the pin disconnecting guide wheel 840 is mounted on the fixed base 400 and the wheel surface of the pin disconnecting guide wheel 840 abuts against the pin disconnecting guide surface 831, the pin disconnecting guide block 830 drives the main body sliding rod 810 to move horizontally and longitudinally, and the main body sliding rod 810 further drives the pin disconnecting plate 820 to move horizontally and longitudinally, so that the pins 11 positioned in the pin disconnecting accommodation groove 821 can move horizontally and longitudinally, thereby disconnecting pins from adjacent pins are realized;
In the third stage of the movement of the plugging movement rod 600, the plugging driving part 700 continues to drive the plugging movement rod 600 to extend, the plugging movement rod 600 drives the plugging sliding seat 500 to continue to slide horizontally, and the plugging sliding seat 500 drives the disconnecting main body 800 and the disconnecting auxiliary 900 thereon to continue to move horizontally, so that the plugging ends 12 of the pins 11 can be plugged into the plugging holes 21 of the housing 20;
When the plugging end 12 of the pin 11 is plugged into the plugging hole 21 of the housing 20, the plugging driving part 700 drives the plugging moving rod 600 to shrink in the opposite direction, firstly, the pin cutting guide wheel 930 slides in the opposite direction along the cutting auxiliary guide groove 610, so that the pin cutting holding block 920 is separated from the pin cutting holding groove 821, the pin cutting holding block 920 does not hold the touch end 13, and meanwhile, the cutting holding pin 921 is separated from the through hole 14 and the cutting holding hole 822, so that the pin 11 can be smoothly separated from the pin cutting holding groove 821; secondly, the plugging driving part 700 continues to drive the plugging moving rod 600 to shrink in the opposite direction, the plugging moving rod 600 drives the cutting main body part 800 and the cutting auxiliary part 900 to integrally return in the opposite direction through the plugging sliding seat 500, meanwhile, as a reset spring (not shown) is connected between the main body sliding rod 810 and the plugging sliding seat 500, the reset spring can drive the cutting main body part 800 to reset, so that the pin cutting accommodating groove 821 on the pin cutting plate 820 can be connected with the material strip discharging end 311b again, and preparation is made for the next pin 11 to be in place and cut off; here, since the lead cutting press block 920 is already separated from the lead cutting receiving groove 821, the lead cutting press block 920 does not hinder the lead 11 from entering the lead cutting receiving groove 821.
Next, the structural design principle of the pin plugging device 32 will be described:
1. The plugging moving rod 600 is provided with a cutting auxiliary guide groove 610, a pin cutting guide wheel 930 is slidingly accommodated in the cutting auxiliary guide groove 610, one end of a middle connecting rod 940 is connected with the pin cutting guide wheel 930, and the other end of the middle connecting rod 940 is connected with the auxiliary sliding rod 910; through the structural design, on one hand, when two adjacent pins 11 need to be cut off, the pin cutting and pressing block 920 presses and holds the touch end 13 of the pin 11, and meanwhile, the cutting and pressing pin 921 can pass through the through hole 14 and enter the cutting and pressing hole 822, so that the cutting stability of the pin 11 is improved; on the other hand, when the pin 11 needs to be plugged into the plugging hole 21 of the housing 20, the pin cutting and pressing block 920 presses and holds the touch end 13 of the pin 11, and meanwhile, the cutting and pressing pin 921 can pass through the through hole 14 and enter the cutting and pressing hole 822, so that the accuracy and stability of the pin 11 during plugging are ensured; on the other hand, the pin cutting press block 920 is separated from the pin cutting receiving groove 821 in time, so that the inserted pin 11 is not blocked by the pin cutting press block 920, and meanwhile, the pin cutting press block 920 does not block the new pin 11 from entering the pin cutting receiving groove 821 again;
2. By arranging the cutting main body piece 800, the cutting main body piece 800 not only can move horizontally and longitudinally, but also can move horizontally and transversely, the cutting main body piece 800 moving horizontally and longitudinally realizes cutting of pins, and the cutting main body piece 800 moving horizontally and transversely realizes splicing of pins; it should be noted that, the cutting body 800 moves in the horizontal longitudinal direction, that is, the cutting body 800 moves along the direction perpendicular to the lead main panel, so that the lead can be cut more effectively;
3. by arranging the cutting auxiliary piece 900, the cutting auxiliary piece 900 is effectively matched with the cutting main body piece 800, and the cutting auxiliary piece 900 presses and holds the pins, so that the pins are more stable in the cutting and inserting processes;
4. On the one hand, the pin cutting and pressing block 920 presses and holds the touching end 13 of the pin 11, on the other hand, the cutting and pressing pin 921 can pass through the through hole 14 and enter the cutting and pressing hole 822, so that the pin is doubly fixed, and the stability and accuracy of the pin in the cutting and inserting processes can be better ensured.
As shown in fig. 11, further, a stopper 510 is disposed on the plugging sliding seat 500, a first blocking piece 410 and a second blocking piece 420 are disposed on the fixed base 400, the first blocking piece 410 and the second blocking piece 420 are spaced apart from each other, and the stopper 510 is movable between the first blocking piece 410 and the second blocking piece 420. In this way, in the sliding process of the plugging sliding seat 500, the plugging sliding seat 500 is only displaced within the designated range due to the limiting action of the first blocking piece 410 and the second blocking piece 420 on the limiting block 510, so that the accurate positioning of the main body 800 and the auxiliary 900 is ensured.
As shown in fig. 9, further, the tape transport mechanism 33 further includes a tape holding structure 340. The tape holding structure 340 includes: the material belt pressing fixed block 341 and the material belt pressing movable block 342. The material belt pressing fixed block 341 is fixed on the material belt transmission track 310, the material belt pressing movable block 342 is slidably arranged on the material belt pressing fixed block 341, a compression spring (not shown) is arranged between the material belt pressing fixed block 341 and the material belt pressing movable block 342, and the material belt pressing movable block 342 abuts against the wheel surface of the material belt transmission roller 320. In this way, the belt pressing movable block 342 is continuously abutted against the surface of the belt conveying roller 320 under the action of the elastic force of the pressing spring, so that the belt 10 is extruded between the belt pressing movable block 342 and the belt conveying roller 320, the belt conveying roller 320 is continuously reciprocated under the action of the force of the belt conveying convex block 321 in the rotating process, and meanwhile, the belt conveying convex block 321 can continuously enter the through hole 14 of the belt 10, so that the smoothness of the belt 10 in the conveying process is improved.
The automatic assembly equipment provided by the invention is mainly used for feeding and transporting the shell 20, so that the shell 20 can reach a designated position, and the pin plugging device 32 is matched, so that the pin 11 can be accurately plugged into the plugging hole 21 of the shell 20 by the pin plugging device 32; the pin plugging device 32 is mainly used for cutting off each pin 11 in the material tape 10, and is matched with the shell conveying device 31 to accurately plug the cut-off pins 11 in the plugging holes 21 of the shell 20; by arranging the shell conveying device 31 and the pin plugging device 32, the traditional manual operation is replaced, and the mechanical automation production level of enterprises is improved.
The above examples illustrate only a few embodiments of the invention, which are described in detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.