阅读说明：本技术 一种空气压缩机、电机及气体动压推力轴承 (Air compressor, motor and pneumatic dynamic pressure thrust bearing ) 是由 华青松 仙存妮 邱瑞林 魏建新 李胜永 刘亚波 于 2020-04-28 设计创作，主要内容包括：本发明公开了一种空气压缩机、电机及气体动压推力轴承,其中气体动压推力轴承包括轴承座、底箔片、分瓣式波纹箔片和分瓣式顶箔片。底箔片上设置有铆钉,分瓣式波纹箔片和分瓣式顶箔片上开设有与铆钉配合的铆钉孔,分瓣式波纹箔片和分瓣式顶箔片依次穿过底箔片的铆钉实现三者的铆接连接,该种连接方式相对于现有技术中藕接连接的方式,铆钉与铆钉孔的加工难度相对较低,从而在一定程度上降低了气体动压推力轴承的加工难度。(The invention discloses an air compressor, a motor and a gas dynamic pressure thrust bearing, wherein the gas dynamic pressure thrust bearing comprises a bearing seat, a bottom foil, a split corrugated foil and a split top foil. The rivet is arranged on the bottom foil, the rivet hole matched with the rivet is formed in the split type corrugated foil and the split type top foil, the split type corrugated foil and the split type top foil sequentially penetrate through the rivet of the bottom foil to achieve riveting connection of the split type corrugated foil and the split type top foil, the rivet and the rivet hole are relatively low in processing difficulty compared with a coupling connection mode in the prior art, and therefore the processing difficulty of the gas dynamic pressure thrust bearing is reduced to a certain extent.)

1. A gas dynamic pressure thrust bearing, comprising:

a bearing seat (1);

the bottom foil (2) is a circular bottom foil, the bottom foil (2) is mounted on the inner wall of the bearing seat (1), a plurality of groups of rivet sets are arranged on the bottom foil (2), each group of rivet sets comprises a plurality of rivets (21), and the plurality of rivets (21) are arranged along the radial direction of the bottom foil (2);

the split type corrugated foil (3) is a fan-shaped corrugated foil, the split type corrugated foil (3) is installed on the bottom foil (2), one end of the split type corrugated foil (3) is a first free end, a first fixed end is arranged at the other end of the split type corrugated foil (3), a first fixing plate (5) is arranged on the first fixed end, and a first rivet hole matched with the rivet (21) is formed in the first fixing plate (5);

split type top foil (4) is fan-shaped top foil, split type top foil (4) is installed on split type ripple foil (3), the one end of split type top foil (4) is the second free end, the other end of split type top foil (4) is provided with the second stiff end, be provided with second fixed plate (6) on the second stiff end, second fixed plate (6) are connected with split type top foil (4) through swash plate (7), the one end of swash plate (7) can compress tightly with split type ripple foil (3) with the top of the ripple that first fixed plate (5) are connected, the other end of swash plate (7) with second fixed plate (6) are connected, seted up on second fixed plate (6) with rivet (21) complex second rivet hole.

2. The aerodynamic thrust bearing according to claim 1, wherein the split corrugated foil (3) is integrally formed with the first stationary plate (5);

the split type top foil piece (4), the inclined plate (7) and the second fixing plate (6) are integrally formed.

3. The aerodynamic thrust bearing according to claim 1, wherein the split top foil (4) is a copper alloy foil, the swash plate (7) and the second fixing plate (6) are copper alloy plates, and upper surfaces of the split top foil (4) and the swash plate (7) and the second fixing plate (6) are provided with a fluororesin layer.

4. The aerodynamic thrust bearing according to claim 1, wherein the split corrugated foil (3) is provided with arc-shaped energy-absorbing grooves (31), the arc-shaped energy-absorbing grooves (31) are parallel to an outer arc of the split corrugated foil (3), and the number of the arc-shaped energy-absorbing grooves (31) is at least two.

5. The aerodynamic thrust bearing according to claim 1, wherein the number of the split corrugated foils (3) and the split top foils (4) is 3 to 10.

6. The aerodynamic thrust bearing according to claim 1, wherein the bottom foil (2) is provided with a plurality of positioning grooves (22) on a circumference thereof, the plurality of positioning grooves (22) being uniformly distributed along the circumference of the bottom foil (2);

and the bearing seat (1) is provided with a positioning boss (8) corresponding to the positioning groove (22).

7. The aerodynamic thrust bearing of claim 1, further comprising a transition foil for adjusting the stiffness of the top foil layer, the transition foil being located between the split top foil (4) and the split corrugated foil (3), the transition foil being a corrugated foil or the transition foil being a flat foil.

8. Aerodynamic thrust bearing according to claim 1, characterized in that said bottom foil (2) is integrally formed with said rivet (21).

9. An electric machine comprising a gas dynamic pressure thrust bearing as claimed in any one of claims 1 to 8.

10. An air compressor comprising an electric motor, said electric motor being a gas dynamic pressure thrust bearing as recited in claim 9.

Technical Field

The invention relates to the technical field of air compressors, in particular to an air compressor, a motor and a gas dynamic pressure thrust bearing.

Background

A gas bearing is a sliding bearing that uses a gas as a lubricant.

The foil type gas dynamic pressure thrust bearing is one of gas bearings and comprises a top foil, a corrugated foil, a bottom foil and a bearing seat, wherein the bearing seat is a cylindrical annular bearing seat, the top foil and the corrugated foil are generally of a split structure, the bottom foil is of an integral structure, and a mounting hole matched with a rotor is formed in the bottom foil. Specifically, the periphery of the bottom foil is connected with the inner wall of the bearing seat, and the bottom foil, the corrugated foil and the top foil are sequentially stacked from bottom to top. The corrugated foil is an elastic foil, and can be slightly deformed under the action of pneumatic force in the operation process of the bearing, so that the self-adaptability of the bearing is enhanced.

Disclosure of Invention

In view of the above, the present invention provides a gas dynamic pressure thrust bearing to reduce the processing difficulty of the gas dynamic pressure thrust bearing. The invention also provides an air compressor and a motor.

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

a gas dynamic pressure thrust bearing comprising:

a bearing seat;

the bottom foil is a circular bottom foil, the bottom foil is mounted on the inner wall of the bearing seat, a plurality of groups of rivet sets are arranged on the bottom foil, each group of rivet sets comprises a plurality of rivets, and the plurality of rivets are arranged along the radial direction of the bottom foil;

the split type corrugated foil is a fan-shaped corrugated foil and is arranged on the bottom foil, one end of the split type corrugated foil is a first free end, the other end of the split type corrugated foil is provided with a first fixed end, a first fixed plate is arranged on the first fixed end, and a first rivet hole matched with the rivet is formed in the first fixed plate;

split type top foil piece is fan-shaped top foil piece, split type top foil piece is installed on the split type ripple foil piece, the one end of split type top foil piece is the second free end, the other end of split type top foil piece is provided with the second stiff end, be provided with the second fixed plate on the second stiff end, the second fixed plate passes through the swash plate and is connected with split type top foil piece, the one end of swash plate can compress tightly with split type ripple foil piece with the corrugated top that first fixed plate is connected, the other end of swash plate with the second fixed plate is connected, seted up on the second fixed plate with rivet complex second rivet hole.

Preferably, in the above aerodynamic thrust bearing, the split corrugated foil is formed integrally with the first fixing plate;

the split top foil, the inclined plate and the second fixing plate are integrally formed.

Preferably, in the aerodynamic thrust bearing, the split top foil is a copper alloy foil, the swash plate and the second fixing plate are copper alloy plates, and a fluororesin layer is provided on upper surfaces of the split top foil, the swash plate and the second fixing plate.

Preferably, in the above aerodynamic thrust bearing, the split corrugated foil is provided with arc-shaped energy-absorbing grooves, the arc-shaped energy-absorbing grooves are parallel to the outer arcs of the split corrugated foil, and the number of the arc-shaped energy-absorbing grooves is at least two.

Preferably, in the above aerodynamic thrust bearing, the number of the split corrugated foils and the split top foil is 3 to 10.

Preferably, in the aerodynamic thrust bearing, positioning grooves are formed in the circumference of the bottom foil, and the number of the positioning grooves is multiple and is uniformly distributed along the circumference of the bottom foil;

and the bearing seat is provided with a positioning boss corresponding to the positioning groove.

Preferably, in the aerodynamic thrust bearing, the aerodynamic thrust bearing further includes a transition foil for adjusting the rigidity of the top foil layer, the transition foil is located between the split top foil and the split corrugated foil, and the transition foil is a corrugated foil or the transition foil is a flat foil.

Preferably, in the above-described gas dynamic pressure thrust bearing, the bottom foil is formed integrally with the rivet.

A motor comprising a gas dynamic pressure thrust bearing according to any one of the above aspects.

An air compressor comprises a motor, wherein the motor is the aerodynamic thrust bearing in the scheme.

According to the technical scheme, the gas dynamic pressure thrust bearing comprises a bearing seat, a bottom foil, a split corrugated foil and a split top foil. The rivet is arranged on the bottom foil, the rivet hole matched with the rivet is formed in the split type corrugated foil and the split type top foil, the split type corrugated foil and the split type top foil sequentially penetrate through the rivet of the bottom foil to achieve riveting connection of the split type corrugated foil and the split type top foil, the rivet and the rivet hole are relatively low in processing difficulty compared with a coupling connection mode in the prior art, and therefore the processing difficulty of the gas dynamic pressure thrust bearing is reduced to a certain extent.

The scheme also discloses a motor which comprises a gas dynamic pressure thrust bearing, wherein the gas dynamic pressure thrust bearing is recorded in any one scheme. Since the aerodynamic thrust bearing has the technical effects, the motor with the aerodynamic thrust bearing also has the same technical effects, and the details are not repeated herein.

The scheme also discloses an air compressor which comprises a motor, wherein the motor is recorded by the scheme. Because the motor has the technical effects, the air compressor with the motor also has the same technical effects, and the details are not repeated herein.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a gas dynamic pressure thrust bearing provided in an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a split top foil according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a split corrugated foil according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a bottom foil according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a split top foil, a split corrugated foil, and a bottom foil riveted together according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a bearing seat according to an embodiment of the present invention.

1. The bearing seat comprises a bearing seat, 2, a bottom foil, 21, a rivet, 22, a positioning groove, 3, a split corrugated foil, 31, an arc-shaped energy absorption groove, 4, a split top foil, 5, a first fixing plate, 6, a second fixing plate, 7, an inclined plate, 8 and a positioning boss.

Detailed Description

The invention discloses a gas dynamic pressure thrust bearing, which aims to reduce the processing difficulty of the gas dynamic pressure thrust bearing. The invention also discloses an air compressor and a motor.

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. 1-6, the present invention discloses a gas dynamic pressure thrust bearing, which includes a bearing seat 1, a bottom foil 2, a split corrugated foil 3 and a split top foil 4.

The bearing seat 1 is a cylindrical annular bearing seat.

The bottom foil 2 is a circular bottom foil, and the bottom foil 2 is mounted on the inner wall of the bearing seat 1 and is perpendicular to the axis of the bearing seat 1. The bottom foil 2 is provided with a mounting hole matched with the rotor.

As shown in fig. 1 and 4, a plurality of sets of rivets are disposed on the bottom foil 2, each set of rivets includes a plurality of rivets 21, and the plurality of rivets 21 are disposed along a radial direction of the bottom foil 2.

The split corrugated foils 3 are fan-shaped corrugated foils, and the number of the split corrugated foils 3 is multiple. The split type corrugated foil 3 is positioned on the upper end face of the bottom foil 2, and the split type corrugated foils 3 are uniformly distributed around the axis of the bottom foil 2.

As shown in fig. 1 and 3, one end of the split corrugated foil 3 is a first free end, and the other end of the split corrugated foil 3 is a first fixed end. It should be noted here that one end and the other end of the split corrugated foil 3 refer to positions where two radii of the split corrugated foil 3 are located.

The first fixing end is provided with a first fixing plate 5, so that the split corrugated foil 3 is fixed on the bottom foil 2. A first rivet hole matched with the rivet 21 is formed in the first fixing plate 5, and the first rivet hole can be matched with a group of rivet groups on the bottom foil 2.

The split corrugated foil 3 deforms under the action of pneumatic force, and the first free end of the split corrugated foil 3 can freely move along the circumferential direction of the bottom foil 2 to balance the circumferential deformation of the split corrugated foil caused by the pneumatic force.

The split top foil 4 is a fan-shaped top foil, the number of the split top foils 4 is multiple, and the split top foils 4 are uniformly distributed around the axis of the bottom foil 2. As shown in fig. 1, the split top foil 4 is located on the upper end surface of the split corrugated foil 3

As shown in fig. 1 and 2, one end of the split top foil 4 is a second free end, and the other end of the split top foil 4 is a second fixed end. It should be noted here that one end and the other end of the split top foil 4 refer to positions of two radii of the split top foil 4.

As shown in fig. 5, a second fixing plate 6 is disposed on the second fixing end to fix the split top foil 4 to the bottom foil 2. Second fixed plate 6 is connected with split type top foil 4 through swash plate 7, and the one end of swash plate 7 can compress tightly on the corrugated top that split type ripple foil 3 and first fixed plate 5 are connected, and the other end of swash plate 7 is connected with second fixed plate 6, has seted up on second fixed plate 6 with rivet 21 complex second rivet hole, the second rivet hole can with a set of rivet group cooperation on the end foil 2.

The split-type top foil 4 deforms along with the split-type corrugated foil 3 under the action of pneumatic force, and the second free end of the split-type top foil 4 can freely move along the circumferential direction of the bottom foil 2 to balance the circumferential deformation of the split-type top foil due to the pneumatic force.

In this scheme, the number of the split type corrugated foils 3 is equal to that of the split type top foils 4, and the number of the split type corrugated foils 3 and the split type top foils 4 is equal to that of the rivet groups.

A gap is arranged between the first free end of the split type corrugated foil 3 and the first fixed end of the adjacent split type corrugated foil 3, and a space is provided for the movement of the first free end.

A gap is arranged between the second free end of the split top foil 4 and the second fixed end of the adjacent split top foil 4, so that a space is provided for the movement of the second free end.

The first fixing plate 5 of the split type corrugated foil 3 can be attached to the upper end surface of the bottom foil 2, and the lower surface of the split type corrugated foil 3 (the lower surface of the split type corrugated foil is a plane where the wave troughs of the corrugations of the split type corrugated foil 3 are located) can also be attached to the upper end surface of the bottom foil 2.

Because be provided with the ripple on split type ripple foil 3, split type ripple foil 3 can be great relatively in the thickness of 2 directions of perpendicular to bottom foil, split type top foil 4 is the plain foil, in order to realize being connected of split type top foil 4 and bottom foil 2, need set up swash plate 7 at the stiff end of split type top foil 4, second fixed plate 6 is connected with swash plate 7, second fixed plate 6 is located the up end of first fixed plate 5 and arranges with first fixed plate 5 is range upon range of, high transition between second fixed plate 6 and split type top foil 4 can be realized to swash plate 7, guarantee that second fixed plate 6 and first fixed plate 5 are effectively connected.

The utility model discloses a gaseous dynamic pressure thrust bearing includes bearing frame 1, end foil 2, split type ripple foil 3 and split type top foil 4, be provided with rivet 21 on the end foil 2, set up on split type ripple foil 3 and the split type top foil 4 with rivet 21 complex rivet hole, split type ripple foil 3 and split type top foil 4 pass end foil 2's rivet 21 in proper order and realize three's riveting connection, this kind of connected mode is for the mode of coupling connection among the prior art, the processing degree of difficulty of rivet 21 and rivet hole is lower relatively, thereby the processing degree of difficulty of gaseous dynamic pressure thrust bearing has been reduced to a certain extent.

The bottom foil 2, the split corrugated foil 3 and the split top foil 4 are riveted, the manufacturing process of the gas dynamic pressure thrust bearing is simple, and large-scale application can be implemented under the condition of low cost.

In order to improve the wholeness of split type ripple foil 3 to improve split type ripple foil 3's use strength, split type ripple foil 3 and first fixed plate 5 integrated into one piece in this scheme.

The connection between the split type corrugated foil 3 and the first fixing plate 5 is not limited to the connection manner of integral molding, and the split type corrugated foil 3 and the first fixing plate 5 may be welded to each other, or the split type corrugated foil 3 and the first fixing plate 5 are bonded to each other.

In order to improve the wholeness of split type top foil 4 to improve split type top foil 4's use intensity, split type top foil 4 and swash plate 7 and second fixed plate 6 integrated into one piece in this scheme, split type top foil 4, swash plate 7 and 6 three integrated into one piece of second fixed plate promptly.

The connection among the split top foil 4, the inclined plate 7 and the second fixing plate 6 is not limited to the connection mode of integral molding, and the split top foil 4, the inclined plate 7 and the second fixing plate 6 may be welded to each other, or the split top foil 4, the inclined plate 7 and the second fixing plate 6 may be bonded to each other.

The split top foil 4 is a copper alloy foil, the inclined plate 7 and the second fixing plate 6 are copper alloy plates, and the upper surfaces of the split top foil 4, the inclined plate 7 and the second fixing plate 6 are provided with a fluorine resin layer.

The split top foil 4, the inclined plate 7 and the second fixing plate 6 are all of a copper alloy-fluororesin double-layer composite structure, in the copper alloy-fluororesin double-layer composite structure, the copper alloy can be one of tin bronze, beryllium bronze or copper nickel tin alloy, and the fluororesin can be tetrafluoroethylene and hexafluoropropylene copolymer (FEP), or a mixture of tetrafluoroethylene, hexafluoropropylene copolymer and polytetrafluoroethylene.

The thickness of the split type top foil 4 of the copper alloy-fluororesin double-layer composite structure can be as low as 0.05mm, the thickness of the split type top foil 4 can be as high as 5mm, and the thickness of the split type top foil 4 is reduced, so that the overall size of the gas dynamic pressure thrust bearing is reduced, and the compactness of the gas dynamic pressure thrust bearing is improved.

In a specific embodiment of the solution, the total thickness of the split top foil 4 is 0.1mm, wherein the thickness of the copper alloy layer is 0.07mm and the thickness of the fluororesin layer is 0.03 mm.

In another embodiment of the solution, the top foil has a total thickness of 0.15mm, wherein the copper alloy layer has a thickness of 0.12mm and the fluororesin layer has a thickness of 0.03 mm.

In addition, the copper alloy-fluororesin double-layer composite structure has good binding force, the working durability of the gas dynamic pressure thrust bearing is prolonged, and the service life of the gas dynamic pressure thrust bearing is longer.

The fluororesin layer is a self-lubricating coating of the rotor and the bearing, has lower dynamic friction coefficient and static friction coefficient, and ensures that the pneumatic dynamic pressure thrust bearing reaches higher bearing efficiency because of low friction power in the starting and normal operation processes.

As shown in fig. 1 and 3, the split corrugated foil 3 is provided with arc-shaped energy-absorbing grooves 31, the arc-shaped energy-absorbing grooves 31 are parallel to the outer arc of the split corrugated foil 3, and the number of the arc-shaped energy-absorbing grooves 31 is at least two.

The arc-shaped energy absorption grooves 31 are through grooves penetrating through the upper surface and the lower surface of the split corrugated foil 3.

When the gas dynamic pressure thrust bearing works, the raised corrugations of the split corrugated foil 3 deform under the action of gas pressure and gradually approach to a plane, the arc-shaped energy absorption grooves 31 can deform to absorb the deformation of a part of the raised corrugations, so that the failure of the gas dynamic pressure thrust bearing caused by the fact that the split corrugated foil 3 is pressed into the plane under the limit condition is avoided, meanwhile, the processing technology of the arc-shaped energy absorption grooves 31 is simple, and the processing cost of the split corrugated foil 3 is reduced.

In addition, the arc-shaped energy absorption grooves 31 can also reduce the weight of the split type corrugated foil 3, reduce the force borne by the riveting position, prolong the service life of the split type corrugated foil 3 and further prolong the service life of the gas dynamic pressure thrust bearing.

The arc-shaped energy absorption grooves 31 are formed in the split type corrugated foil 3, and the material cost of the split type corrugated foil 3 can be reduced.

The arc-shaped energy absorption groove 31 of the split type corrugated foil 3 can also be changed into a plurality of circular energy absorption holes which are arranged in an arc shape.

In a specific embodiment of the solution, the number of the split corrugated foils 3 and the split top foils 4 is 3-10.

Specifically, the number of the split corrugated foil 3 and the split top foil 4 is 3, 4, 5, 6 … … 9, or 10.

The number of the split corrugated foils 3 and the split top foils 4 is not limited to the above number, the specific selection number is determined by those skilled in the art according to actual needs, and is not specifically limited herein, and in addition, the number of the split corrugated foils 3 and the split top foils 4 is determined to be an integer.

In an embodiment of the present disclosure, as shown in fig. 6, positioning grooves 22 are disposed on the circumference of the bottom foil 2, the number of the positioning grooves 22 is multiple and is uniformly distributed along the circumference of the bottom foil 2, and correspondingly, a positioning boss 8 corresponding to the positioning groove 22 needs to be disposed on the bearing seat 1. The positioning groove 22 is matched with the positioning boss 8 to realize the circumferential fixation of the bottom foil 2 in the bearing seat 1.

The aerodynamic thrust bearing disclosed by the scheme further comprises a transition thin sheet (not shown in the figure) for adjusting the rigidity of the top foil layer, wherein the transition foil is positioned between the split type top foil 4 and the split type corrugated foil 3, and meanwhile, the transition foil can also increase the internal damping of the aerodynamic thrust bearing, so that the stability of the bearing in the operation process is ensured.

The transition foil between the split top foil 4 and the split corrugated foil 3 may be one or more.

In a specific embodiment of the present solution, the transition foil may be a corrugated foil, and the distance between the corrugation width of the transition foil and the adjacent corrugation is different from the distance between the corrugation width of the split corrugated foil 3 and the adjacent corrugation. Here, the corrugation width is the length of the corrugation in the circumferential direction of the base foil sheet 2, and the distance between adjacent corrugations is also the length in the circumferential direction of the base foil sheet 2.

In the embodiment where the transition foil is a corrugated foil, the transition foil may also be provided with energy absorbing grooves.

In another particular embodiment of the solution, the transition foil is a flat foil.

The transition foil and the split top foil 4 and/or the split corrugated foil 3 can be connected by welding, bonding or riveting.

The connection mode of the transition foil and the split-type top foil 4 and/or the split-type corrugated foil 3 is not limited to the above-mentioned several connection modes, and other connection modes that can connect the transition foil and the split-type top foil 4 and/or the split-type corrugated foil 3 may also be used, so that the connection strength of the transition foil and the split-type top foil 4 and/or the split-type corrugated foil 3 can be ensured, and the specific connection mode is not specifically limited herein.

In a particular embodiment of the solution, the rivets 21 of the bottom foil 2 are formed integrally with the bottom foil 2.

Specifically, the rivet 21 is a rivet 21 that is punched out integrally with the base foil 2 by a punching process.

The number of the rivets 21 of each group of rivet groups is 2-4, and the number of the rivet holes of the split type top foil 4 and the split type corrugated foil 3 of the rivets 21 is equal to that of the rivets 21.

The scheme also discloses a motor which comprises a gas dynamic pressure thrust bearing, wherein the gas dynamic pressure thrust bearing is recorded in any one scheme.

Since the aerodynamic thrust bearing has the technical effects, the motor with the aerodynamic thrust bearing also has the same technical effects, and the details are not repeated herein.

The scheme also discloses an air compressor which comprises a motor, wherein the motor is recorded by the scheme.

Because the motor has the technical effects, the air compressor with the motor also has the same technical effects, and the details are not repeated herein.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.