Auxiliary equipment for processing ceramic insulator mud of overhead transmission line
The invention is filed on 2017, 01, 13 and has the application number of 2017100256045 and the name of
A divisional application of Chinese patent application of an auxiliary machinery for processing ceramic insulator mud of an overhead transmission line.
Technical Field
The invention relates to the field of auxiliary equipment for processing ceramic insulators, in particular to auxiliary equipment for processing ceramic insulators of overhead transmission lines.
Background
The insulator is a special insulating control part and can play an important role in an overhead transmission line, the insulator is mostly used for a telegraph pole in the early years, one end of a high-voltage wire connecting tower which is slowly developed is hung with a plurality of disc-shaped insulators, the insulator is usually made of glass or ceramics for increasing creepage distance, the insulator is called as an insulator, the insulator cannot be failed due to various electromechanical stresses caused by changes of environment and electric load conditions, otherwise, the insulator cannot play a great role, and the use and the service life of the whole line can be damaged; the insulator is generally commonly used as a ceramic insulator, a glass fiber reinforced plastic insulator, a composite insulator and a semiconductor insulator.
The porcelain insulator is the most used insulator at present, the main material for manufacturing the porcelain insulator is slurry, but the slurry for forming the porcelain insulator needs to be specially processed, the slurry for the porcelain insulator needs to remove fine metals contained in the slurry, wherein the fine metals with the highest content are iron components, most of the slurry iron removal processes are performed by adopting manual iron absorption processing operation at present, and the sucked iron slag does not need subsequent recovery processing, so that the slurry iron removal process occupies a large amount of labor force, the iron removal efficiency is low, and the sucked iron slag does not need recovery utilization, thereby causing resource waste. In view of the above, the invention provides auxiliary equipment for processing the ceramic insulator pug of the overhead transmission line.
Disclosure of Invention
In order to make up the defects of the prior art, the invention provides auxiliary equipment for processing the ceramic insulator pug of the overhead transmission line.
The technical problem to be solved by the invention is realized by adopting the following technical scheme.
An auxiliary device for processing a ceramic insulator mud material of an overhead transmission line comprises a bracket, a bar-shaped magnet, a clamping manipulator, a movable iron removing device, an iron slag conveying and drying device and an iron slag screening device; the support be bilayer structure, support upper strata left side is provided with the slurry transport groove, the slurry transport groove is upper end opening lower extreme confined rectangle structure, and the slurry transport groove front end has seted up out the slurry mouth, bar magnet puts side by side in the slurry transport groove on support upper strata, the clamp is got the manipulator and is installed in removal deironing device left side top, remove the deironing device and be located slurry transport groove right side, drying device is located removal deironing device right side below position department is carried to the iron sediment, iron sediment screening plant installs and carries drying device dead ahead at the iron sediment.
Furthermore, the clamping manipulator comprises a deflection motor, a rotating arm support, a clamping push rod, a lifting support, a clamping guide rod, a guide spring, a clamping claw, a clamping bayonet lock, an opening and closing push rod and an opening and closing hinge; the rotary arm support is in a Z-shaped structure, the lower end of the rotary arm support is connected with an output shaft of a deflection motor, the clamping push rod is positioned between the rotary arm support and the lifting frame, the upper end of the clamping push rod is connected with the upper end of the rotating arm support, the lower end of the clamping push rod is connected with the upper end surface of the lifting frame platform, clamping lug seats are arranged on the lower end surface of the lifting frame platform, the clamping guide rods are positioned on the left side and the right side of the clamping push rod, the guide spring is wound on the clamping guide rods in a sleeved mode, the number of the clamping claws is two, the clamping claws are positioned on the left side and the right side below the lifting frame platform, the upper ends of the clamping claws are connected with the clamping lug seats on the lower end surface of the lifting frame platform through clamping bayonet pins, arc-shaped clamping grooves are arranged in, the upper end of the opening and closing push rod is connected with the lifting stand through an opening and closing hinge, and the lower end of the opening and closing push rod is connected with the inner side wall of the clamping jaw through an opening and closing hinge; can drive through the motor that shifts and press from both sides the rotary motion of getting the jack catch in the horizontal plane, can drive through pressing from both sides the push rod of getting and get the elevating movement of getting the jack catch on the perpendicular, can control through opening and closing the push rod and get opening and closing of getting the jack catch to can press from both sides and get and release bar magnet, press from both sides and get the manipulator and can carry out the motion of a translation rotation two degree of freedom directions altogether in the space, the motion is quick nimble, and it is high to snatch release stability, can carry out quick clamp to the bar magnet that has inhaled iron impurity in mud.
Further, the mobile iron removing device comprises a traveling mechanism, a wiping mechanism and a material pushing mechanism; the wiping mechanism is positioned above the travelling mechanism, and the material pushing mechanism is fixed right in front of the wiping mechanism; the walking mechanism comprises a moving platform, a driving motor, a driving shaft, a driving wheel, a driving belt pulley, a driven belt pulley, a transmission belt, a driven shaft, a driven wheel and a walking guide rail; the driving motor is a double-shaft output motor, the driving motor is arranged under the moving platform, one end of the driving shaft is connected with an output shaft of the driving motor, the other end of the driving shaft is provided with a driving wheel, a driving belt pulley is fixed at the middle position of the driving shaft, a driven belt pulley is connected with the driving belt pulley through a transmission belt, the driven belt pulley is arranged on a driven shaft, two ends of the driven shaft are respectively provided with a driven wheel, and the driven wheel and the driving wheel are both arranged on the walking guide; the traveling mechanism is used for moving the iron removing device to travel forwards and backwards, does not deviate in the traveling process, and is stable and reliable.
Furthermore, the wiping mechanism comprises a wiping bracket, a transmission motor, a transmission lead screw, a wiping slide seat, a support bracket, a conversion motor, a rotating disk, a wiping block, a wiping push rod, a wiping hinge, a wiping rotating pin and a limiting spring; the left side and the right side of the wiping bracket are respectively symmetrically provided with wiping ear seats, a movable sliding rail is arranged between the wiping ear seats, a guide sliding rail is arranged in parallel in front of the movable sliding rail, a transmission motor is fixed on the wiping bracket, one end of a transmission screw rod is connected with an output shaft of the transmission motor, the other end of the transmission screw rod is connected with the wiping ear seats on the wiping bracket, the middle part of the wiping sliding seat is provided with an internal thread hole which is matched and installed with the transmission screw rod, the bottom end of the wiping sliding seat is provided with a wiping chute which is matched and installed with the movable sliding rail, the rear end of a support bracket is fixed on the wiping sliding seat, the front end of the support bracket is installed on the guide sliding rail, the front end of the support bracket is provided with a dragging seat, the dragging seat is provided with an, the cleaning device comprises a rotating disk, a cleaning block, a rotating lug seat, limiting springs, a rotating disk, a cleaning push rod, a cleaning hinge, a cleaning rotating pin, a limiting spring, a rotating spring seat, a limiting spring, a rotating spring, a limiting spring and a cleaning spring, wherein the rotating disk is arranged between the rotating disk and the cleaning block in an inclined mode; the cleaning block and the rotating disc are vertically arranged, a T-shaped plate is arranged at the upper end of the cleaning block, a reciprocating cleaning block is arranged at the lower end of the cleaning block, a semicircular reciprocating clamping groove is formed in the reciprocating cleaning block, and a semicircular flexible gasket is nested in the semicircular reciprocating clamping groove; the cleaning block is driven to tilt upwards by the contraction motion of the cleaning push rod, when the bar-shaped magnet clamped by the clamping manipulator reaches the lower part of the cleaning block, the cleaning block is driven to turn downwards by the extension motion of the cleaning push rod, when the semicircular reciprocating clamping groove on the cleaning block is attached to the bar-shaped magnet, the motion of the cleaning push rod is stopped, the forward and reverse rotation of the transmission screw rod is driven by the forward and reverse rotation of the transmission motor, so that the left and right reciprocating movement of the cleaning slide seat is realized, the iron slag on the upper surface of the bar-shaped magnet adsorbed with the iron slag is pushed into the material pushing groove, then the cleaning block is driven to tilt upwards by the contraction motion of the cleaning push rod, and the rotating disk is driven to rotate by the rotation of the conversion motor, so that the cleaning block rotates 180 degrees, the cleaning block is driven to turn upwards by the extension motion of the cleaning push rod, when the semicircular reciprocating clamping groove, the movement of the wiping push rod is stopped, and the iron slag on the lower surface of the bar-shaped magnet adsorbed with the iron slag is pushed down into the material pushing groove through the left-right reciprocating movement of the wiping slide seat, so that the process of pushing down the iron slag on the whole surface of the bar-shaped magnet is completed.
Further, the material pushing mechanism comprises a material pushing groove, a material pushing rack, a material pushing plate, a material pushing motor and a material pushing gear; a discharge chute is arranged at the right side end of the material pushing chute, material pushing racks are fixed on the front side of the material pushing chute in parallel, a fixed seat is arranged at the upper end of a material pushing plate, an inclined push plate is arranged at the lower end of the material pushing plate, the material pushing plate is arranged in the material pushing chute, a material pushing motor is fixed on the fixed seat at the upper end of the material pushing plate, a material pushing gear is arranged on an output shaft of the material pushing motor, and the material pushing; the pushing gear is driven to rotate by the rotation of the pushing motor, and the pushing gear and the pushing rack drive the pushing plate to move horizontally by meshing motion, so that the iron slag in the pushing groove is pushed to the iron slag conveying and drying device.
Further, the iron slag conveying and drying device comprises a conveying bracket, a conveying motor, a conveying driving wheel, a conveying driven wheel, a conveying transmission belt, an iron slag conveying belt and an electric heating rod; the upper end of the middle part of the conveying support is provided with an inverted U-shaped mounting rack, the conveying motor is positioned outside the conveying support, the conveying driving wheel is connected with an output shaft of the conveying motor, the conveying driving wheel is connected with the conveying driven wheel through a conveying transmission belt, the conveying driven wheel is connected with an iron slag conveying belt, the electric heating rod is arranged in the inverted U-shaped mounting rack at the upper end of the middle part of the conveying support and is of a grid-shaped structure; the iron slag conveying and drying device is mainly used for conveying iron slag in a molten state, and electric heating rods are used for drying the iron slag in the conveying process, so that the iron slag becomes dry powder.
Further, the iron slag screening device comprises a screening support, a vibrating screen, a vibrating branch chain, a primary material collecting box and a secondary material collecting box; the middle part of the screening support is provided with a bayonet, the vibrating screen is positioned right above the screening support, the vibrating branch chain is positioned between the screening support and the vibrating screen, the front end of the vibrating screen is in an open state, the bottom end surface of the vibrating screen is provided with screening holes, the first-stage material collecting box is arranged at the bayonet in the middle part of the screening support, and the second-stage material collecting box is arranged in front of the vibrating screen; the vibration branched chain comprises a vibration table, a fixed table, a vibration telescopic rod, an upper hinge and a lower hinge, and the number of the vibration telescopic rod, the number of the upper hinge and the number of the lower hinge are four; the vibration telescopic rod is positioned between the vibration table and the fixed table, the vibration table is positioned right above the fixed table, the upper end of the vibration telescopic rod is connected with the vibration table through an upper hinge, and the lower end of the vibration telescopic rod is connected with the fixed table through a lower hinge; the vibration branch chain adopts a parallel mechanism in a 4-RPR form, can move in three freedom directions in a translation and rotation mode in space, has strong bearing capacity and high movement stability, and can drive the vibration sieve to move through the vibration branch chain, thereby screening the dried iron slag.
Compared with the prior art, the invention has the following advantages:
(1) the invention can remove iron components in the ceramic insulator pug, improves the insulating property of the ceramic insulator, can recycle the iron slag after the removal of the ceramic insulator, has various functions and high automation degree, and improves the production efficiency of the ceramic insulator.
(2) The clamping manipulator can move in two freedom directions of translation and rotation in space, is quick and flexible in movement, has high stability in grabbing and releasing, and can quickly clamp the bar-shaped magnet which absorbs iron impurities in slurry.
(3) The movable iron removing device has the functions of walking, moving wiping iron removal and pushing, and can be used for removing iron slag on the upper surface and the lower surface of the bar-shaped magnet which adsorbs iron impurities through transposition, so that the device is quick and convenient and has a good iron removing effect.
(4) The iron slag conveying and drying device is mainly used for conveying iron slag in a molten state, and drying the iron slag in the conveying process by using the electric heating rod, so that the iron slag becomes dry powder.
(5) The iron slag screening device can move in three freedom directions of one translation and two rotations in space, has strong bearing capacity and high movement stability, and can screen the dried iron slag.
Drawings
The invention is further illustrated with reference to the following figures and examples.
FIG. 1 is a schematic perspective view of the present invention;
fig. 2 is a schematic perspective view of the gripping robot;
FIG. 3 is a schematic perspective view (from top to bottom) of the mobile iron removing device of the present invention;
FIG. 4 is a schematic perspective view (from bottom to top) of the mobile iron removal device of the present invention;
FIG. 5 is a schematic perspective view of the wiping mechanism and the pushing mechanism of the present invention;
FIG. 6 is a schematic perspective view of the wiping mechanism of the present invention;
FIG. 7 is a schematic perspective view of the pushing mechanism of the present invention;
FIG. 8 is a schematic perspective view of the iron slag conveying and drying apparatus and the iron slag screening apparatus according to the present invention;
FIG. 9 is a schematic perspective view of the iron slag screening apparatus according to the present invention;
fig. 10 is a schematic perspective view of the vibrating branched chain of the present invention.
Detailed Description
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further explained below by combining the specific drawings.
As shown in fig. 1 to 10, an auxiliary device for processing ceramic insulator pug of an overhead transmission line comprises a bracket 1, a bar-shaped magnet 4, a clamping manipulator 5, a movable iron removing device 6, an iron slag conveying and drying device 7 and an iron slag screening device 8; support 1 be bilayer structure, 1 upper strata left side of support is provided with the slurry transport groove, the slurry transport groove is upper end opening lower extreme confined rectangle structure, and the slurry transport groove front end has seted up out the slurry mouth, bar magnet 4 places side by side in the slurry transport groove on 1 upper strata of support, press from both sides and get manipulator 5 and install in 6 left sides top of removing deironing device, it is located the slurry transport groove right side to remove deironing device 6, drying device 7 is located 6 right sides below position departments of removing deironing device to the iron slag, iron slag screening plant 8 is installed and is carried drying device 7 dead ahead at the iron slag.
The clamping manipulator 5 comprises a deflection motor 51, a rotating arm support 52, a clamping push rod 53, a lifting stand 54, a clamping guide rod 55, a guide spring 56, a clamping claw 57, a clamping bayonet 58, an opening and closing push rod 59 and an opening and closing hinge 510; the rotary arm support 52 is of a Z-shaped structure, the lower end of the rotary arm support 52 is connected with an output shaft of a deflection motor 51, a clamping push rod 53 is positioned between the rotary arm support 52 and a lifting stand 54, the upper end of the clamping push rod 53 is connected with the upper end of the rotary arm support 52, the lower end of the clamping push rod 53 is connected with the upper end surface of the lifting stand 54, clamping lug seats are arranged on the lower end surface of the lifting stand 54, clamping guide rods 55 are positioned on the left side and the right side of the clamping push rod 53, guide springs 56 are wound on the clamping guide rods 55, the number of the clamping jaws 57 is two, the clamping jaws 57 are positioned on the left side and the right side below the lifting stand 54, the upper ends of the clamping jaws 57 are connected with the clamping lug seats on the lower end surface of the lifting stand 54 through clamping pins 58, arc-shaped clamping grooves are arranged in the middle positions of the lower ends of the clamping jaws, the lower end of the opening and closing push rod 59 is connected with the inner side wall of the clamping claw 57 through an opening and closing hinge 510; can drive through the motor 51 that shifts and press from both sides the rotary motion of getting jack catch 57 in the horizontal plane, can drive through pressing from both sides the elevating movement who gets jack catch 57 on the vertical plane of getting push rod 53, can control through opening and closing push rod 59 and press from both sides the opening and the closure of getting jack catch 57, thereby can press from both sides and get and release bar magnet 4, it can carry out the motion of a translation rotation two degree of freedom directions in total to press from both sides manipulator 5 in the space to get, the motion is quick nimble, and it is high to snatch release stability, can press from both sides fast the bar magnet 4 who inhales iron impurity in.
The mobile iron removing device 6 comprises a travelling mechanism 61, a wiping mechanism 62 and a material pushing mechanism 63; the wiping mechanism 62 is positioned above the traveling mechanism 61, and the material pushing mechanism 63 is fixed right in front of the wiping mechanism 62; the travelling mechanism 61 comprises a moving platform 611, a driving motor 612, a driving shaft 613, a driving wheel 614, a driving belt pulley 615, a driven belt pulley 616, a transmission belt 617, a driven shaft 618, a driven wheel 619 and a travelling guide rail 6110; the driving motor 612 is a double-shaft output motor, the driving motor 612 is installed right below the moving platform 611, one end of a driving shaft 613 is connected with an output shaft of the driving motor 612, the other end of the driving shaft 613 is provided with a driving wheel 614, a driving belt pulley 615 is fixed at the middle position of the driving shaft 613, a driven belt pulley 616 is connected with the driving belt pulley 615 through a transmission belt 617, the driven belt pulley 616 is installed on a driven shaft 618, two ends of the driven shaft 618 are respectively provided with a driven wheel 619, and the driven wheel 619 and the driving wheel 614 are both installed on a walking guide rail; the traveling mechanism 61 is used for moving the iron removing device 6 to travel forwards and backwards, and the traveling mechanism is stable and reliable without deviation in the traveling process.
The wiping mechanism 62 comprises a wiping bracket 621, a transmission motor 622, a transmission lead screw 623, a wiping slide 624, a support bracket 625, a conversion motor 626, a rotating disk 627, a wiping block 628, a wiping push rod 629, a wiping hinge 6210, a wiping rotating pin 6211 and a limit spring 6212; the left side and the right side of the wiping support 621 are symmetrically provided with wiping ear seats respectively, a movable sliding rail is arranged between the wiping ear seats, a guide sliding rail is arranged in front of the movable sliding rail side by side, the transmission motor 622 is fixed on the wiping support 621, one end of the transmission screw 623 is connected with an output shaft of the transmission motor 622, the other end of the transmission screw 623 is connected with the wiping ear seat on the wiping support 621, the middle part of the wiping sliding seat 624 is provided with an internal thread hole matched with the transmission screw 623, the bottom end of the wiping sliding seat 624 is provided with a wiping sliding groove matched with the movable sliding rail, the rear end of the support bracket 625 is fixed on the wiping sliding seat 624, the front end of the support bracket 625 is arranged on the guide sliding rail, the front end of the support bracket 625 is provided with a dragging seat, the dragging seat is provided with an arc groove, the, the lower end of the front side of the rotating disc 627 is provided with a rotating lug seat, a wiping push rod 629 is obliquely arranged between the rotating disc 627 and the wiping block 628, one end of the wiping push rod 629 is connected with the rotating disc 627 through a wiping hinge 6210, the other end of the wiping push rod 629 is connected with the wiping block 628 through a wiping hinge 6210, the wiping block 628 is connected with the rotating lug seat at the lower end of the front side of the rotating disc 627 through a wiping rotating pin 629, limiting springs 6210 are respectively and symmetrically positioned at the left side and the right side of the wiping push rod 629, one end of each limiting spring 6212 is connected with the rotating disc 627, and the other end; the cleaning block 628 and the rotating disc 627 are vertically arranged, a T-shaped plate is arranged at the upper end of the cleaning block 628, a reciprocating cleaning block is arranged at the lower end of the cleaning block 628, a semicircular reciprocating clamping groove is formed in the reciprocating cleaning block, and a semicircular flexible gasket is nested in the semicircular reciprocating clamping groove; the wiping block 628 is driven to tilt upwards by the contraction motion of the wiping push rod 629, when the bar-shaped magnet 4 gripped by the gripper manipulator 5 reaches the position below the wiping block 628, the wiping block 628 is driven to turn downwards by the extension motion of the wiping push rod 629, when the semicircular reciprocating slot on the wiping block 628 is engaged with the bar-shaped magnet 4, the motion of the wiping push rod 629 is stopped, the forward and reverse rotation of the transmission screw 623 is driven by the forward and reverse rotation of the transmission motor 622, so that the left and right reciprocating movement of the wiping slide 624 is realized, the iron dross on the upper surface of the bar-shaped magnet 4 adsorbed with the iron dross is pushed into the material pushing groove 631, then the wiping block 628 is driven to tilt upwards by the contraction motion of the wiping push rod 629, and the rotation of the rotating disk 627 is driven by the rotation of the conversion motor 622, so that the wiping block 628 is rotated 180 degrees, and the wiping block 628 is driven to turn upwards by the extension, when the semicircular reciprocating groove of the wiping block 628 is engaged with the bar-shaped magnet 4, the movement of the wiping push rod 629 is stopped, and the iron slag on the lower surface of the bar-shaped magnet 4 to which the iron slag is adsorbed is pushed down into the push groove 631 by the left and right reciprocating movement of the wiping slide 624, thereby completing the process of pushing down the iron slag on the entire surface of the bar-shaped magnet 4.
The pushing mechanism 63 comprises a pushing trough 631, a pushing rack 632, a pushing plate 633, a pushing motor 634 and a pushing gear 635; a discharge chute is arranged at the right side end of the material pushing groove 631, the material pushing racks 632 are fixed on the front side of the material pushing groove 631 side by side, a fixed seat is arranged at the upper end of the material pushing plate 633, an inclined push plate is arranged at the lower end of the material pushing plate 633, the material pushing plate 633 is arranged in the material pushing groove 631, the material pushing motor 634 is fixed on the fixed seat at the upper end of the material pushing plate 633, a material pushing gear 635 is arranged on an output shaft of the material pushing motor 634, and the material pushing; the rotation of the pushing gear 635 is driven by the rotation of the pushing motor 634, and the pushing gear 635 and the pushing rack 632 drive the pushing plate 633 to move horizontally through the engagement motion, so as to push the iron slag in the pushing groove 631 to the iron slag conveying and drying device 7.
The iron slag conveying and drying device 7 comprises a conveying bracket 71, a conveying motor 72, a conveying driving wheel 73, a conveying driven wheel 74, a conveying transmission belt 75, an iron slag conveying belt 76 and an electric heating rod 77; an inverted U-shaped mounting frame is arranged at the upper end of the middle of the conveying support 71, the conveying motor 72 is positioned outside the conveying support 71, the conveying driving wheel 73 is connected with an output shaft of the conveying motor 72, the conveying driving wheel 73 is connected with the conveying driven wheel 74 through a conveying transmission belt 75, the conveying driven wheel 74 is connected with an iron slag conveying belt 76, an electric heating rod 77 is arranged in the inverted U-shaped mounting frame at the upper end of the middle of the conveying support 71, and the electric heating rod 77 is of a grid-shaped structure; the iron slag conveying and drying device 7 is mainly used for conveying iron slag in a molten state, and drying the iron slag in the conveying process by using an electric heating rod 77, so that the iron slag becomes dry powder.
The iron slag screening device 8 comprises a screening support 81, a vibrating screen 82, a vibrating branch 83, a primary material collecting box 84 and a secondary material collecting box 85; the middle part of the screening support 81 is provided with a bayonet, the vibrating screen 82 is positioned right above the screening support 81, the vibrating branch chain 83 is positioned between the screening support 81 and the vibrating screen 82, the front end of the vibrating screen 82 is in an open state, the bottom end surface of the vibrating screen 82 is provided with screening holes, the primary material collecting box 84 is arranged at the bayonet in the middle part of the screening support 81, and the secondary material collecting box 85 is arranged in front of the vibrating screen 82; the vibrating branched chain 83 comprises a vibrating table 831, a fixed table 832, a vibrating telescopic rod 833, an upper hinge 834 and a lower hinge 835, and the number of the vibrating telescopic rod 833, the number of the upper hinge 834 and the number of the lower hinge 835 are four; the vibrating telescopic rod 833 is positioned between the vibrating table 831 and the fixed table 832, the vibrating table 831 is positioned right above the fixed table 832, the upper end of the vibrating telescopic rod 833 is connected with the vibrating table 831 through an upper hinge 834, and the lower end of the vibrating telescopic rod 833 is connected with the fixed table 832 through a lower hinge 835; the vibration branch chain 83 adopts a 4-RPR parallel mechanism, can move in three freedom directions in a translation and rotation mode in space, has strong bearing capacity and high movement stability, and can drive the vibration sieve 82 to move through the vibration branch chain 83, so that the dried iron slag is screened.
The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are given by way of illustration of the principles of the present invention, and that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.