阅读说明：本技术 清洁件、清洁组件和机器人 (Cleaning member, cleaning assembly and robot ) 是由 黄忠葵 赵坤雷 宫海涛 杨勇 于 2021-09-30 设计创作，主要内容包括：本发明公开了一种清洁件、清洁组件和机器人,所述清洁件具有旋转中心,所述清洁件在垂直于其旋转轴线的截面的外边沿为平滑曲线,所述平滑曲线由多段导数连续变化的曲线单元首尾相连围成,所述外边沿连续两点与所述旋转中心连线距离不相等且所述外边沿与所述旋转中心之间存在至少一条长径和至少一条短径。根据本发明实施例的清洁件能够避免清洁不到的区域,具有清洁效果好等优点。(The invention discloses a cleaning piece, a cleaning assembly and a robot, wherein the cleaning piece is provided with a rotating center, the outer edge of the section of the cleaning piece, which is vertical to the rotating axis of the cleaning piece, is a smooth curve, the smooth curve is formed by connecting a plurality of sections of curve units with continuously changed derivatives end to end, the distances between two continuous points of the outer edge and the connecting line of the rotating center are unequal, and at least one long diameter and at least one short diameter are arranged between the outer edge and the rotating center. The cleaning piece provided by the embodiment of the invention can avoid the region which can not be cleaned, and has the advantages of good cleaning effect and the like.)

1. A cleaning piece is characterized in that the cleaning piece is provided with a rotation center, the outer edge of a section of the cleaning piece perpendicular to the rotation axis of the cleaning piece is a smooth curve, the smooth curve is formed by connecting a plurality of sections of curve units with continuously changed derivatives end to end, the distance between two continuous points of the outer edge and the connection line of the rotation center is unequal, and at least one long diameter and at least one short diameter exist between the outer edge and the rotation center.

2. A cleaning member according to claim 1, wherein said major diameters alternate with said minor diameters and/or are co-linear across said centre of rotation.

3. The cleaning member according to claim 1, wherein adjacent two of said curve units are symmetrically disposed with a major diameter and/or a minor diameter.

4. The cleaning member according to claim 1, wherein an angle between each adjacent two of said major diameters is equal, an angle between each adjacent two of said minor diameters is equal, a length of each of said major diameters is equal and a length of each of said minor diameters is equal.

5. The cleaning member according to claim 1, wherein the cleaning member is rotationally symmetric in a section perpendicular to the rotation axis and has a rotation angle equal to an included angle between adjacent two of the major diameters.

6. A cleaning assembly, comprising:

at least two cleaning members according to any one of claims 1-5;

and the driving device is in transmission connection with the two cleaning pieces respectively so as to drive the two cleaning pieces to rotate.

7. The cleaning assembly of claim 6, wherein the distance between the two centers of rotation is always equal.

8. The cleaning assembly of claim 7, wherein the distance between the two centers of rotation is equal to the total length of the one major diameter and the one minor diameter.

9. A cleaning assembly according to claim 6, wherein the two cleaning members are rotated at angular velocities of the same magnitude but in opposite directions.

10. The cleaning assembly of claim 6 wherein the reduction in the radial length of one of the cleaning members from the major to minor diameter is equal to the increase in the radial length of the other cleaning member from the minor to major diameter in the same unit of time.

11. A cleaning assembly according to claim 6, wherein the outer edges of the two cleaning members are held tangentially by the drive means.

12. The cleaning assembly of claim 6, further comprising a transmission mechanism, wherein the transmission mechanism comprises at least two rotating shafts, the two rotating shafts are respectively connected with the two rotating centers, and the driving device drives the two cleaning members to rotate through the transmission mechanism.

13. A robot, characterized in that it comprises a cleaning assembly according to any one of claims 6-12.

Technical Field

The invention relates to the technical field of cleaning equipment, in particular to a cleaning piece, a cleaning assembly with the cleaning piece and a robot with the cleaning assembly.

Background

The cleaning robot in the related art cleans the floor by the matching rotation of two cleaning pieces, the shape of the cleaning pieces is circular or reuleaux polygon, but the contact between the cleaning pieces is not proper, so that an area which cannot be cleaned is generated in the cleaning process.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides the cleaning piece, which can avoid an area which cannot be cleaned and has the advantages of good cleaning effect and the like.

The invention also provides a cleaning assembly with the cleaning piece.

The invention also provides a robot with the cleaning assembly.

In order to achieve the above object, an embodiment according to a first aspect of the present invention provides a cleaning member having a rotation center, wherein an outer edge of a cross section perpendicular to the rotation axis of the cleaning member is a smooth curve, the smooth curve is formed by connecting a plurality of curve units with continuously changing derivatives end to end, two continuous points of the outer edge are not equidistant from a line connecting the rotation center, and at least one long diameter and at least one short diameter are arranged between the outer edge and the rotation center.

According to the cleaning piece provided by the embodiment of the invention, the area which cannot be cleaned can be avoided, and the cleaning piece has the advantages of good cleaning effect and the like.

In addition, the cleaning member according to the above embodiment of the present invention may have the following additional technical features:

according to one embodiment of the invention, the major and minor diameters are arranged alternately and/or co-linearly across the centre of rotation.

According to one embodiment of the invention, two adjacent curve units are symmetrically arranged with a long diameter and/or a short diameter.

According to an embodiment of the present invention, an angle between each two adjacent long paths is equal, an angle between each two adjacent short paths is equal, a length of each long path is equal, and a length of each short path is equal.

According to one embodiment of the invention, the cleaning elements are rotationally symmetrical in a section perpendicular to the axis of rotation and the angle of rotation is equal to the angle between two adjacent major diameters.

An embodiment according to a second aspect of the invention proposes a cleaning assembly comprising: at least two cleaning members according to embodiments of the first aspect of the invention; and the driving device is in transmission connection with the two cleaning pieces respectively so as to drive the two cleaning pieces to rotate.

According to the cleaning assembly provided by the embodiment of the invention, by using the cleaning piece provided by the embodiment of the first aspect of the invention, the region which cannot be cleaned can be avoided, and the cleaning assembly has the advantages of good cleaning effect and the like.

According to one embodiment of the invention, the distance between the two said centres of rotation is always equal.

According to an embodiment of the invention, the distance between two of said centres of rotation is equal to the total length of said one major and said one minor path.

According to one embodiment of the invention, the two cleaning elements are rotated at the same angular speed but in opposite directions.

According to one embodiment of the present invention, the length of one of the cleaning members decreases from the longer diameter to the shorter diameter by an amount equal to the length of the other cleaning member increases from the shorter diameter to the longer diameter in the same unit time.

According to one embodiment of the invention, the outer edges of the two cleaning members are held tangentially by the drive means.

According to one embodiment of the invention, the cleaning assembly further comprises a transmission mechanism, the transmission mechanism at least comprises two rotating shafts, the two rotating shafts are respectively connected with the two rotating centers, and the driving device drives the two cleaning pieces to rotate through the transmission mechanism.

Embodiments according to a third aspect of the invention propose a robot comprising a cleaning assembly according to embodiments of the second aspect of the invention.

According to the robot provided by the embodiment of the invention, by utilizing the cleaning assembly provided by the embodiment of the second aspect of the invention, the region which cannot be cleaned can be avoided, and the advantages of good cleaning effect and the like are achieved.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

figure 1 is a schematic view of a cleaning element according to one embodiment of the invention.

Figure 2 is a schematic view of a rotation process of a cleaning assembly according to an embodiment of the present invention.

Fig. 3 is a schematic view of a cleaning member according to another embodiment of the present invention.

Fig. 4 is a schematic view illustrating a rotation process of a cleaning assembly according to another embodiment of the present invention.

Fig. 5 is a schematic view of a cleaning member according to another embodiment of the present invention.

Fig. 6 is a schematic view illustrating a rotation process of a cleaning assembly according to another embodiment of the present invention.

Fig. 7 is a schematic view of a cleaning member according to another embodiment of the present invention.

Fig. 8 is a schematic view illustrating a rotation process of a cleaning assembly according to another embodiment of the present invention.

Fig. 9 is a schematic view of a cleaning member according to another embodiment of the present invention.

Figure 10 is a schematic view of a rotation process of a cleaning assembly according to another embodiment of the present invention.

Reference numerals: the cleaning assembly 1, the cleaning member 10, the rotating shaft 100, the rotating center 110, the cleaning main body 200, the curve unit 201, the long diameter 210 and the short diameter 220.

Detailed Description

The present application is based on the discovery and recognition by the inventors of the following facts and problems:

the cleaning robot in the related art cleans the floor by the cooperative rotation of two cleaning pieces, and the shape of the cleaning pieces is circular or reuleaux polygon, but gaps are easily generated between the cleaning pieces, so that an area which cannot be cleaned is generated.

Specifically, when two cleaning members are arranged for a circular cleaning member, there are two ways in which the two cleaning members are intended to rotate tangentially, but a gap is likely to be generated between the two cleaning members due to manufacturing errors of the cleaning members. The other is to slightly interfere the two cleaning members when the two cleaning members are arranged, the two cleaning members are mutually pressed to avoid gaps caused by manufacturing errors, but the rotation resistance of the cleaning members is larger, and the rotation axis of the cleaning members is easy to deviate after long-time use, so that the cleaning members incline.

To the cleaning piece of le luo polygon, realize cleanly through the complementary cooperation of two cleaning pieces, the intention utilizes the longer part of one of them cleaning piece to compensate the shorter part of another cleaning piece, can reduce the gap that can not reach cleanly to a certain extent, and le luo polygon need to the apex angle fillet for guaranteeing that two cleaning pieces are smooth and easy to rotate, leads to two cleaning pieces still to be difficult to closely cooperate, still is difficult to avoid appearing the gap that can not reach cleanly.

In addition, the cleaning members are partially matched in a complementary manner to form a generally regular polygon similar to a reuleaux polygon, but the occurrence of a gap between the two cleaning members is difficult to avoid.

Specifically, the cleaning members in the related art only consider the complementary cleaning of the two cleaning members in the rotating process, and the two cleaning members can locally generate gaps or locally interfere in the rotating process, which easily causes an uncleaned area on the cleaning floor, or easily causes the cleaning members to locally deform and warp when interfering, which causes the resistance of the motor to suddenly increase, the running power of the motor to be unstable, the service life of the motor to be reduced, and the service life of the cleaning unit to be reduced.

For example, in the case of two generally polygonal cleaning members of the related art, if the vertex of one of the cleaning members is exactly fitted to the side of the other, when the cleaning members are rotated by an angle smaller than the rotational symmetry angle (for example, the generally triangular cleaning members are rotated by 60 degrees), a gap is generated when the cleaning members are fitted to each other, and if the distance between the cleaning members is shortened to eliminate the gap, the cleaning members interfere with each other when the vertex of one of the cleaning members is rotated again to be fitted to the side of the other.

The inventors of the present application have conducted extensive studies to find that the cause of the above problems is due to the related art due to the curvature arrangement of the cleaning member edge shape.

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention. Furthermore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

A cleaning member 10 according to an embodiment of the present invention is described below with reference to the accompanying drawings.

As shown in fig. 1 to 10, the cleaning member 10 according to the embodiment of the present invention has a rotation center 110, and the outer edge of the cleaning member 10 in a cross section perpendicular to the rotation axis thereof is a smooth curve surrounded by curve units 201 with a plurality of derivatives varying continuously end to end, the two consecutive points of the outer edge are not equidistant from the line connecting the rotation center 110, and at least one long diameter 210 and at least one short diameter 220 are present between the outer edge and the rotation center 110.

The length of minor diameter 220 is less than the length of major diameter 210.

Those skilled in the art will appreciate that a "reuleaux polygon" is generally a regular polygon, but its edges are not continuously conductive curves, and at its vertices, non-curved corners are formed.

It should be understood that the curve unit 201 is a curve from the short path 220 to the next long path 210 or a curve from the long path 210 to the next short path 220. The number of curve units 201 is the sum of the number of long paths 210 and the number of short paths 220.

According to the cleaning piece 10 provided by the embodiment of the invention, by means of making the distances between two continuous points on the outer edge of the cleaning piece 10 and the connecting line of the rotation center 110 unequal, and the existence of at least one long diameter 210 and at least one short diameter 220 between the outer edge and the rotation center 110, compared with the technical scheme of the circular cleaning piece in the related art, the long diameter 210 of one cleaning piece 10 can be used for making up the short diameter 220 of the other cleaning piece 10, so that the two cleaning pieces 10 can be rotated in a complementary fit manner for cleaning, and the generation of gaps which cannot be cleaned due to manufacturing errors is reduced.

Moreover, as the two cleaning pieces 10 can form a complementary cleaning mode, compared with the technical scheme of the circular cleaning piece in the related art, the two cleaning pieces 10 do not need to be extruded with each other, so that the rotation resistance of the cleaning pieces 10 can be reduced, the cleaning pieces 10 can rotate more smoothly, the deformation and the deviation of the rotation center 110 caused by long-time use can be avoided, and the cleaning pieces 10 can be prevented from inclining; in addition, the situations that the robot runs unstably, positioning deviation and image acquisition equipment are fuzzy due to the fact that the cleaning piece generates eccentric shaking when rotating due to abrasion of the squeezing part of the cleaning piece in different degrees caused by long-time use can be avoided.

In addition, the applicant of the present application has found through extensive research that if there is a straight line or a discontinuous conductive curve at the outer edge of the cleaning elements 10, the two cleaning elements 10 are prone to generate gaps when being complementarily fitted, and the present application can make the two cleaning elements 10 constantly fit when being complementarily fitted and avoid generating gaps between the two cleaning elements 10 when being complementarily fitted and rotated, thereby avoiding generating an area which cannot be cleaned, by making the outer edge of the cleaning element 10 in a section perpendicular to the rotation axis of the cleaning element 10 a smooth curve which is defined by a curve unit 201 with continuously changing multiple derivatives in an end-to-end manner. The cleaning effect of the cleaning member 10 can thereby be improved.

Therefore, the cleaning member 10 according to the embodiment of the present invention can avoid the area which cannot be cleaned, and has the advantages of good cleaning effect, etc.

A cleaning member 10 according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

Advantageously, as shown in fig. 1-10, the major diameters 210 alternate with the minor diameters 220 and/or are co-linear with the center of rotation 110. This facilitates the complementation of the major and minor diameters 210 and 220 by the cooperation of the two cleaning elements 10, avoiding the creation of uncleaned areas.

More advantageously, as shown in fig. 1-10, two adjacent curve units 201 are symmetrically arranged with the long diameter 210 and/or the short diameter 220. This facilitates control of the distance between the two cleaning elements 10 during rotation, facilitating the complementation of the major and minor diameters 210 and 220 by the cooperation of the two cleaning elements 10.

Specifically, as shown in fig. 1 to 10, the angle between each adjacent two of the long paths 210 is equal, the angle between each adjacent two of the short paths 220 is equal, the length of each of the long paths 210 is equal, and the length of each of the short paths 220 is equal. This facilitates the complementation of the major and minor diameters 210 and 220 by the cooperation of the two cleaning elements 10, avoiding the creation of uncleaned areas.

More specifically, in any cell angle, the decrease in the radial length of one curve cell 201 from the long diameter 210 to the short diameter 220 is equal to the increase in the radial length of the adjacent curve cell 201 from the short diameter 220 to the long diameter 210.

For example, as shown in fig. 1, the unit angle a is equal to the unit angle a', when the diameter length changes by the value B-C.

More specifically, as shown in fig. 1 to 10, the cleaning member 10 is rotationally symmetric in a section perpendicular to the rotation axis and has a rotation angle equal to an included angle between two adjacent major diameters 210. Specifically, the plurality of curve units 201 are identical. This further facilitates the complementation of major and minor diameters 210 and 220 by the cooperation of the two cleaning elements 10, further avoiding the creation of uncleaned areas.

Specifically, the cleaning member 10 includes a rotation shaft 100 and a cleaning main body 200.

In one embodiment of the invention, as shown in figures 9 and 10, a cleaning element 10 having a major diameter 210, the center of rotation 110 of which is not centered in the dimension, is not perfectly circular in shape. Therefore, complementary cleaning to a certain degree can be realized, a gap is avoided between the two cleaning pieces 10 in the rotating process, the shape is concise and attractive, and the processing and the manufacturing are convenient.

In another embodiment of the invention, shown in figures 7 and 8, two cleaning elements 10 of longer diameter 210, which are oval in shape, have their axes of rotation centered in the dimension. This may increase the frequency of alternation between the major axis 210 and the minor axis 220 and improve cleaning efficiency compared to the embodiment with a single major axis 210.

In another embodiment of the invention, as shown in figures 5 and 6, three cleaning elements 10 having a major diameter 210 are generally triangular in shape with their axes of rotation at the center of their dimensions. This may increase the frequency of alternation between the major axis 210 and the minor axis 220 and improve the cleaning effect compared to the two major axis 210 embodiments.

In another embodiment of the invention, as shown in figures 3 and 4, four cleaning elements 10 having a major diameter 210 are generally quadrilateral in shape with their axes of rotation at the center of their dimensions. Thus, compared with the three long paths 210, the frequency of the alternation between the long paths 210 and the short paths 220 can be increased, and the cleaning effect can be improved.

In another embodiment of the present invention, as shown in figures 1 and 2, five cleaning elements 10 having a major diameter 210 are generally pentagonal in shape with their axes of rotation at the center of their dimensions. This increases the frequency of alternation between the long diameter 210 and the short diameter 220 and improves the cleaning effect compared to the four long diameter 210 embodiments.

In summary, when the number of the long paths 210 of the cleaning members 10 is increased, the frequency of the alternation of the long paths 210 and the short paths 220 is increased, which is beneficial to improve the cleaning effect. When the major axis 210 and the minor axis 220 of the cleaning element 10 are the same, the number of the major axis 210/the minor axis 220 is positively correlated with the absolute value of the variation value of the curve unit 201 from the rotation center in the unit angle, i.e., the larger the number of the major axis 210/the minor axis 220, the smaller the included angle between the major axis 210 and the minor axis 220.

The odd number of long diameters 210 is used, and the one, three, and five long diameters 210 are used, and the long diameters 210 are collinear with the short diameters 220. The even numbered embodiment of major axis 210 has two opposing major axes 210 that are collinear, two opposing minor axes 220 that are collinear, and major and minor axes 210 and 220 that are not collinear. Thus, the embodiment with the even-numbered major axis 210 is not as orderly arranged as the embodiment with the odd-numbered major axis 210.

In addition, the larger the number of the major diameters 210, the smaller the difference between the lengths of the major diameters 210 and the minor diameters 220, which results in a reduction in the complementary cleaning effect, since the cleaning member area is limited by the cleaning robot and the two cleaning members 10 are always tangent during the rotation.

Optionally, the length of major diameter 210 is 60-100 millimeters and the length of minor diameter 220 is 40-80 millimeters. This allows cleaning elements 10 to be of reasonable size and allows the major and minor diameters 210 and 220 to be varied without being too large or too small to facilitate rotation of the cleaning elements 10 while ensuring that the cleaning elements 10 are alternately engaged.

The cleaning assembly 1 according to an embodiment of the present invention is described below. The cleaning assembly 1 according to an embodiment of the present invention comprises at least two cleaning members and a drive means.

The cleaning member 10 is the cleaning member 10 according to the above-described embodiment of the present invention. The driving device is respectively in transmission connection with the two cleaning pieces 10 so as to drive the two cleaning pieces 10 to rotate.

According to the cleaning assembly 1 of the embodiment of the invention, by using the cleaning piece 10 of the embodiment of the invention, the region which can not be cleaned can be avoided, and the cleaning effect is good.

Specifically, as shown in fig. 2, 4, 6, 8, and 10, the distance between the two rotation centers 110 is always equal. This facilitates on the one hand the close fit of the two cleaning elements 10 during rotation and avoids deformation and displacement of the cleaning elements 10 due to variations in the distance between the centres of rotation 110.

More specifically, as shown in fig. 2, 4, 6, 8, and 10, the distance between two centers of rotation 110 is equal to the total length of a major diameter 210 and a minor diameter 220. This allows the major diameter 210 of one cleaning element 10 to compensate for the minor diameter 220 of the other cleaning element 10, keeping the cleaning elements 10 in close proximity during rotation.

Advantageously, the two cleaning members 10 are rotated at angular speeds of the same magnitude but in opposite directions. This facilitates the two cleaning members 10 to always align the major diameter 210 of one with the minor diameter 220 of the other during rotation, thereby ensuring a snug fit of the two cleaning members 10 during rotation.

Advantageously, as shown in figures 2, 4, 6, 8 and 10, the reduction in the length of one of the two cleaning elements 10 during the reduction in the length of the diameter from the major diameter 210 to the minor diameter 220 is equal to the increase in the length of the other cleaning element 10 during the increase in the length of the diameter from the minor diameter 220 to the major diameter 210, in the same unit of time. This allows the two cleaning elements 10 to be rotated such that the increase in the radial length of one cleaning element 10 compensates for the decrease in the radial length of the other cleaning element 10, thereby ensuring that the sum of the radial lengths of the two cleaning elements 10 is equal and that the two cleaning elements 10 are closely matched.

Further, as shown in fig. 2, 4, 6, 8 and 10, the outer edges of the two cleaning members 10 are kept tangent by the driving of the driving means. This ensures that the two cleaning elements 10 remain in close engagement at all times during rotation.

In some specific examples of the present invention, as shown in fig. 2, 4, 6, 8 and 10, the cleaning assembly 1 further includes a transmission mechanism, the transmission mechanism includes at least two rotating shafts 100, the two rotating shafts 100 are respectively connected to the two rotating centers 110, and the driving device drives the two cleaning members 10 to rotate through the transmission mechanism.

The transmission mechanism further comprises a reduction gear set.

In one embodiment, the driving device may include a motor, and one motor drives the two rotating shafts 100 through a reduction gear set, respectively.

In another embodiment, the driving device may include two motors, and the two motors respectively drive the two rotating shafts 100 through two reduction gear sets.

This enables the two cleaning elements 10 to be driven in rotation.

Specifically, during rotation of the cleaning members 10, the major diameter 210 of one of the two cleaning members 10 and the minor diameter 220 of the other cleaning member. This allows the major diameter 210 of one cleaning element 10 to be used to complement the minor diameter 220 of the other cleaning element 10, avoiding gaps that cannot be cleaned.

Further, the sum of the distances of the edges of the two cleaning members 10 from the axis of rotation passing through the plane between the axes of rotation of the two cleaning members 10 is equal at all times during the rotation of the cleaning members 10. And gaps which can not be cleaned are avoided.

A robot according to an embodiment of the present invention is described below. A robot according to an embodiment of the invention comprises a cleaning assembly 1 according to the above-described embodiment of the invention.

According to the robot provided by the embodiment of the invention, by using the cleaning assembly 1 provided by the embodiment of the invention, the region which cannot be cleaned can be avoided, and the cleaning effect is good.

Other configurations and operations of the robot according to embodiments of the present invention are known to those of ordinary skill in the art and will not be described in detail herein.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.