Patent Publication Number: US-2021170469-A1

Title: Roll-forming tool for creating a noncircular feature, method of creating a noncircular feature, and method of assembling a pump having a noncircular joint

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 62/683,222, filed on Jun. 11, 2018. The entire disclosures of the above application is incorporated herein by reference. 
    
    
     FIELD 
     The present disclosure relates to a roll-forming tool for creating a noncircular feature such as a joint, a method of creating a noncircular feature such as a joint using the roll-forming tool, and a method of assembling a pump having a noncircular joint. 
     BACKGROUND 
     This section provides background information related to the present disclosure which is not necessarily prior art. 
     Roll-forming, which involves the continuous deformation of a material by two or more rollers, can be used to form enclosed joints. Such roll-formed joints may be used on pumps, such as to retain bearings and/or motor stators, by way of example. To create the roll-formed joint, two or more rollers can be revolved about a central axis to continuously engage a circular lip to deform a first component to engage a second component, thereby forming a joint. However, some joints interconnect components along a noncircular path. The shape of the component periphery is something other than a circle and the joint may be identified as noncircular. The rollers of the roll-forming machine are unable to maintain continuous and concurrent engagement with the component to be deformed as they revolve about the central axis. Instead of the method described above, noncircular roll-formed joints may be created through use of a complicated tool that follows the shape of a profile of the component rather than remaining stationary with respect to the central axis. 
     SUMMARY 
     This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. 
     In various aspects, the subject disclosure provides a method of deforming a noncircular lip. The method includes rotating a roll-forming tool about a longitudinal axis. The roll-forming tool includes a central shaft, a first axle, a second axle, a first roller, and a second roller. The central axis extends along the longitudinal axis. The first axle has a first lateral axis that extends substantially perpendicular to the longitudinal axis. The second axle has a second lateral axis that extends substantially perpendicular to the longitudinal axis. The first roller is rotatably coupled to the first axis and adapted to rotate about the first lateral axis. The second roller is rotatably coupled to the second axis and adapted to rotate about the second lateral axis. The first and second rollers are radially positioned with respect to the longitudinal axis and circumferentially spaced with respect to each other. While rotating the roll-forming tool, the first and second rollers are engaged with the noncircular lip. The method further includes applying a load to the noncircular lip. The load is applied parallel to the longitudinal axis. The method further includes continuing rotating the roll-forming tool about the longitudinal axis. The longitudinal axis remains in a fixed position. Rotating the roll-forming tool causes the first and second rollers to concurrently operably engage the noncircular lip and deform the noncircular lip. 
     In other aspects, the subject disclosure provides a method of assembling a cover to a housing of a pump. The method includes disposing a noncircular plate within a cavity. The cavity is at least partially defined by a noncircular lip. The method further includes rotating a roll-forming tool about a longitudinal axis. The roll-forming tool includes a central shaft, a first axle, a second axle, a first roller, and a second roller. The central shaft extends along the longitudinal axis. The first axle includes a first lateral axis that extends substantially perpendicular to the longitudinal axis. The second axle includes a second lateral axis that extends substantially perpendicular to the longitudinal axis. The first roller is rotatably coupled to the first axle and adapted to rotate about the first lateral axis. The second roller is rotatably coupled to the second axle and adapted to rotate about the second lateral axis. The first and second rollers are radially positioned with respect to the longitudinal axis and circumferentially spaced with respect to each other. While rotating the roll-forming tool, the first and second rollers are engaged with the noncircular lip. The method further includes applying a load to the noncircular lip. The load is applied parallel to the longitudinal axis. The method further includes continuing rotating the roll-forming tool about the longitudinal axis. The longitudinal axis remains in a fixed position. Rotating the roll-forming tool causes the first and second rollers to concurrently operably engage the noncircular lip, deform the noncircular lip, and assemble the cover to the housing. 
     In other aspects, the subject disclosure provides a tool for roll-forming a noncircular lip of a component. The tool includes a central shaft, a first axle, a second axle, a first roller, and a second roller. The central shaft has a longitudinal axis. The central shaft is adapted to rotate about the longitudinal axis. The first and second axles extend from and is fixed to the central shaft. The first axle has a first lateral axis that extends substantially perpendicular to the longitudinal axis. The second axle has a second lateral axis that extends substantially perpendicular to the longitudinal axis. The first roller is rotatably coupled to the first axle and adapted to rotate about the first lateral axis. The second roller is rotatably coupled to the second axle and adapted to rotate about the second lateral axis. The first and second rollers are radially spaced with respect to the longitudinal axis and circumferentially spaced with respect to each other. The first and second rollers are adapted to concurrently operably engage the noncircular lip, and deform the noncircular lip. 
     Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. 
         FIG. 1  is a side view of a roll-forming tool engaging a noncircular lip according to certain aspects of the present disclosure; 
         FIG. 2  is a top view of the roll-forming tool of  FIG. 1  engaging a first portion of the noncircular lip; 
         FIG. 3  is a top view of the roll-forming tool of  FIG. 1  engaging a second portion of the noncircular lip; 
         FIG. 4  is a top view of the roll-forming tool of  FIG. 1  engaging a third portion of the noncircular lip; 
         FIG. 5  is a perspective view of a pump having a housing and a cover according to certain aspects of the present disclosure; 
         FIG. 6  is a partial sectional view of the pump of  FIG. 5  showing a lip of the housing in an undeformed configuration; 
         FIG. 7  is a partial sectional view of the pump of  FIG. 5  showing a lip of the housing in a deformed configuration; 
         FIG. 8  is a top view of another pump according to certain aspects of the present disclosure; and 
         FIG. 9  is a flowchart depicting an example method of assembling the pump of  FIG. 5 , the method including roll-forming a joint of the pump using the roll-forming tool of  FIG. 1 . 
     
    
    
     Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION 
     Example embodiments will now be described more fully with reference to the accompanying drawings. 
     In various aspects, the present disclosure provides a tool for creating a noncircular roll-formed feature, such as a joint. The tool includes at least two rollers that are wide enough to accommodate both the narrowest and widest dimensions of the noncircular feature. The present disclosure also provides a method of roll-forming a noncircular feature and a method of assembling a pump that includes a noncircular joint. Compared to the typical method of following the shape of the noncircular feature with a complex tool, the methods of the present disclosure are quicker, cheaper, and easier to automate. 
     With reference to  FIGS. 1-4 , a roll-forming tool  10  according to certain aspects of the present disclosure is provided. The roll-forming tool  10  may include a central shaft  12  that extends along a longitudinal axis  14 . The roll-forming tool  10  may further include an axle  16  that extends along a lateral axis  18 . The lateral axis  18  of the axle  16  may extend substantially perpendicular to the longitudinal axis  14  of the central shaft  12 . In various aspects, both the central shaft  12  and the axle  16  are substantially cylindrical. 
     The roll-forming tool  10  may also include first and second wheels or rollers  20 ,  22 . In various aspects, the first and second rollers  20 ,  22  may be referred to as “the rollers.” The rollers  20 ,  22  may be rotatably coupled to the axle  16  and adapted to rotate with respect to the axle  16 . More particularly, the rollers  20 ,  22  may be adapted to rotate about the lateral axis  18 . The rollers  20 ,  22  may be radially positioned with respect to the longitudinal axis  14 . The rollers  20 ,  22  may be disposed equidistant from the longitudinal axis  14  of the central shaft  12 . The rollers  20 ,  22  may be circumferentially spaced with respect to each other. The first and second rollers  20 ,  22  may be equally spaced about a circumference of a circle traced by the rollers  20 ,  22  when the roll-forming tool  10  is rotated about the longitudinal axis  14 . In various aspects, the first roller  20  and the second roller  22  are substantially identical. 
     The roll-forming tool  10  may further include a base  24  disposed at a distal end  26  ( FIG. 1 ) of the central shaft  12 . The base  24  may be laterally centered with respect to the longitudinal axis  14 . The axle  16  and the base  24  may be fixed with respect to the central shaft  12 . In various aspects, the axle  16  and the base  24  are integrally formed with the central shaft  12 . 
     The axle  16  may include a first portion  28  having a first axis  29 , and a second portion  30  having a second axis  31 . The first axis  29  and the second axis  31  are collinear with each other and the lateral axis  18 . The first and second portions  28 ,  30  may project from opposing first and second sides  32 ,  34  of the base  24 . In various aspects, the first and second portions  28 ,  30  may be referred to as first and second axles, respectively. The first and second axes  29 ,  31  may be referred to as first and second lateral axes, respectively. 
     The first roller  20  may be rotatably coupled to the first portion  28  of the axle  16 . The second roller  22  may be rotatably coupled to the second portion  30  of the axle  16 . The rollers  20 ,  22  may be laterally fixed to prevent translation along the lateral axis  18  of the axle  16 . In various aspects, inward movement (i.e., toward the longitudinal axis  14 ) of the rollers  20 ,  22  may be at least partially limited by the base  24 . 
     The rollers  20 ,  22  can continuously and concurrently engage a noncircular feature, such as a noncircular lip  50 . In one example, the lip  50  is roll-formed around a noncircular plate  52  ( FIG. 2 ) to create a noncircular joint and retain the plate  52 . The central shaft  12  can be rotated about the longitudinal axis  14  in a first rotational direction  54  ( FIG. 1 ). When the rollers  20 ,  22  engage the noncircular lip  50 , rotation of the central shaft  12  about the longitudinal axis  14  causes the rollers  20 ,  22  to rotate in a second rotational direction  56  ( FIG. 2 ) about the lateral axis  18 . A load may be applied in a downward direction  58  ( FIG. 1 ) so that operable engagement of the rollers  20 ,  22  with the noncircular lip  50  causes the noncircular lip  50  to deform. 
     The rollers  20 ,  22  may be wide enough parallel to the lateral axis  18  to bridge a narrowest portion of a profile of the noncircular lip  50  (see, e.g.,  FIG. 2 ), an intermediate portion of the profile of the noncircular lip  50  ( FIG. 3 ), and a widest portion of the profile of the noncircular lip  50  (see, e.g.,  FIG. 4 ). Thus, the longitudinal axis  14  may remain fixed while the first roller  20  and the second roller  22  concurrently engage the noncircular lip  50  through an entire rotation of the roll-forming tool  10  (i.e., a 360° rotation of the central shaft  12  about the longitudinal axis  14 ). Unlike the typical method of following the noncircular profile with a complex tool having a non-stationary longitudinal axis (not shown), the roll-forming tool  10  of the present disclosure can be used to form a noncircular joint while the longitudinal axis  14  remains fixed and the rollers  20 ,  22  have a circular orbit about the longitudinal axis  14 . 
     With reference to  FIG. 3 , the noncircular lip  50  may at least partially define a first dimension  70  substantially perpendicular to the longitudinal axis  14 . The noncircular lip may at least partially define a second dimension  72  substantially perpendicular to the longitudinal axis  14 . The first dimension  70  may be greater than the second dimension  72 . In one example, the first and second dimensions  70 ,  72  are substantially perpendicular to one another. In various aspects, the first dimension  70  is a maximum dimension and the second dimension  72  is a minimum dimension. In various aspects, a ratio of the first dimension  70  to the second dimension  72  is greater than  1 , optionally greater than or equal to 1.05, optionally greater than or equal to 1.1, optionally greater than or equal to 1.10, optionally greater than or equal to 1.2, optionally greater than or equal to 1.25, optionally greater than or equal to 1.3, optionally greater than or equal to 1.35, optionally greater than or equal to 1.4, optionally greater than or equal to 1.45, and optionally greater than or equal to 1.5. 
     The rollers  20 ,  22  may include respective outer surfaces  74  and inner respective inner surfaces  76 . The inner surfaces  76  may be disposed closer to the longitudinal axis  14  than the outer surfaces  74 . The outer surfaces  74  of the roller  20 ,  22  may be spaced apart by a third dimension  78 . The inner surfaces  76  of the rollers  20 ,  22  may be spaced apart by a fourth dimension  80 . The third dimension  78  may be greater than the fourth dimension  80 . In various aspects, a ratio of the third dimension  78  to the fourth dimension  80  is greater than or equal to 1, optionally greater than or equal to 1.1, optionally greater than or equal to 1.2, optionally greater than or equal to 1.3, optionally greater than or equal to 1.4, optionally greater than or equal to 1.5, optionally greater than or equal to 1.6, optionally greater than or equal to 1.7, optionally greater than or equal to 1.8, optionally greater than or equal to 1.9, and optionally greater than or equal to 2. 
     As described above the rollers  20 ,  22  are wide enough to bridge both the narrowest and the widest portions of the profile of the noncircular lip  50 . Thus, the third dimension  78  of the rollers  20 ,  22  may be greater than or equal to the first dimension  70  of the noncircular lip  50 . The fourth dimension  80  of the rollers  20 ,  22  may be less than or equal to the second dimension  72  of the noncircular lip  50 . 
     Profiles of the plate  52  and noncircular lip  50 , in a plane substantially perpendicular to the longitudinal axis  14 , may be symmetric about two perpendicular axes. More particularly the plate  52  may be symmetric about a first transverse axis substantially parallel to the first dimension  70 , and a second transverse axis substantially perpendicular to the second dimension  72 . However, one skilled in the art would appreciate that other profiles are possible. In one example, the plate  52  and the noncircular lip  50  have a single axis of symmetry (see, e.g., pump  170  of  FIG. 8 ). In another example, the plate  52  and the noncircular lip  50  do not have any axes of symmetry. 
     In various aspects, the roll-forming tool  10  includes exactly two rollers (e.g., the first roller  20  and the second roller  22 ). However, in alternative variations, a roll-forming tool may include additional rollers. For example, a roll-forming tool may optionally include three rollers, four rollers, or five rollers, each roller being radially positioned with respect to the longitudinal axis and circumferentially spaced with respect to the other rollers (not shown). Each roller may be disposed on a separate axle having a separate lateral axis (e.g., when the roll-forming tool includes three rollers, first, second, and third axles may each extend radially from a central shaft, be disposed at about 120° from one another, and include respective, first, second, and third lateral axes about which the respective first, second, and third rollers can rotate). In another example, additional rollers disposed along the axle at different radii to concurrently roll-form other nested features (not shown). 
     With reference to  FIG. 5 , a pump  90  according to certain aspects of the present disclosure is provided. The pump  90  may include a housing  92  and a plate or cover  94 . In one example, the cover  94  is a rear cover that encloses an electronics assembly (not shown) of the pump  90 . The housing  92  may be cast from a molten metal or machined to final shape. The housing  92  may include a lip  96 . The lip  96  may have a noncircular profile. A geometry of the lip  96  may be cast together with the housing  92  or subsequently machined into the housing  92 . The cover  94  may have a noncircular geometry. In various aspects, the cover  94  comprises aluminum. The cover  94  may be stamped or laser cut. Although the cover  94  is shown as a solid, flat plate, it may include different or additional features. The cover  94  may not be flat. By way of example, the cover  94  can include stamped features, such as to increase stiffness. In another example, the cover may include one or more holes, such as for a vent that allows air, but not moisture, to pass in and out of the enclosure. The cover  94  may enclose a chamber (e.g., chamber  118  shown in  FIGS. 6-7 ) of the pump  90 . In various aspects, the pump  90  is an electric water pump (eWP). However, the pump may alternatively be any other type of pump having a noncircular joint (e.g., an electric oil pump (eOP)). Alternatively, a cover may engage a noncircular lip to at least partially enclose a chamber on other assemblies, such as a cooling fan. 
     Referring to  FIG. 6 , the housing  92  is shown with the lip  96  in an undeformed state (i.e., prior to roll-forming). The lip  96  may extend upward from a body  110  of the housing  92 . The lip  96  may at least partially define a cavity  112 . The housing  92  may include a first surface  114  that at least partially forms a base of the cavity  112 . The first surface  114  may include a groove  116 . The groove  116  may extend around an entire perimeter of the cavity  112 . The cover  94  may be placed into the cavity  112  to enclose a chamber  118  into which the electronics assembly may be disposed. 
     The lip  96  may extend around an entire outer perimeter of the cavity  112 . The lip  96  may be adapted to deform inward  120 , toward a center of the cavity  112  upon the application of a force applied in a downward direction  122  (i.e., parallel to a longitudinal axis  123  of the cavity  112 ). The lip  96  may include a second or outer surface  124 , a third or inner surface  126 , and a fourth or top surface  128 . The top surface  128  may extend between the outer surface  124  and the inner surface  126 . The top surface  128  may be adapted to engage the rollers of a roll-forming tool (e.g., rollers  20 ,  22  of the roll-forming tool  10  of  FIGS. 1-4 ). When the rollers engage the top surface  128 , a longitudinal axis of the roll-forming tool (e.g., longitudinal axis  14  of  FIG. 1 ) may be aligned with the longitudinal axis  123  of the cavity  112 . Thus, the top surface  128  may extend substantially perpendicular to both the longitudinal axis  123  of the cavity  112  and the longitudinal axis of the roll-forming tool. 
     The outer surface  124  of the lip  96  may form a first angle  130  with the top surface  128  of the lip  96 . The first angle  130  may be greater than 0° and less than or equal to about 90°. By way of example, the first angle  130  may be greater than or equal to about 60° and less than or equal to about 70°, and optionally greater than or equal to about 63° to less than or equal to about 65°. The inner surface  126  of the lip  96  may form a second angle  132  with the top surface  128  of the lip  96 . The second angle  132  may be greater than 0° and less than or equal to about 90°. By way of example, the second angle  132  may be greater than or equal to about 60° and less than or equal to about 70°, optionally greater than or equal to about 67° and less than or equal to about 69°. The first and second angles  130 ,  132  may have different magnitudes. The first angle  130  may be less than the second angle  132 . The outer surface  124  may include a first length  134  substantially parallel to the longitudinal axis  123  of the cavity  112 . The inner surface  126  may include a second length  136  substantially parallel to the longitudinal axis  123  of the cavity  112 . The first length  134  may be greater than the second length  136 . By way of example, a ratio of the first length to the second length may be greater than 1, optionally greater than or equal to 1.5, optionally greater than or equal to 2, optionally greater than or equal to 2.5, optionally greater than or equal to 3, optionally greater than or equal to 3.5, optionally greater than or equal to 4, optionally greater than or equal to 4.5, and optionally greater than or equal to 5. A noncircular edge  138  may extend around an outer perimeter of the lip  96 . In various alternative aspects, the lip  96  may include different or additional features (e.g., undercuts, perforations) that facilitate deformation in a preferred direction (e.g., inward). 
     The pump  90  may further include a seal  140  that is disposed at least partially within the groove  116 . The seal  140  may be room-temperature-vulcanizing (RTV) silicone, an  0 -ring, a seal-in-place gasket, a noncircular-cross-section seal, or any other appropriate seal known to those skilled in the art. In another aspect, the cover  94  may be coated with rubber for sealing to act as a rubber-coated metal (RCM) gasket (not shown). The seal  140  may engage the cover  94 . 
     With reference to  FIG. 7 , the housing  92  is shown with the lip  96  in a deformed configuration (i.e., after roll-forming). In the deformed configuration, the lip  96  is deformed inward to engage the cover  94 . Thus, the lip  96  and the cover  94  may form a joint  150  to retain the cover  94 . The joint  150  may be noncircular and may extend around an interface between the lip  96  and the cover  94 . The lip  96  may form a hook or inward projection  152 . The cover  94  may be disposed longitudinally between the lip  96  of the housing  92  and the seal  140 . The cover  94  may be disposed in the cavity  112  to enclose the chamber  118 . In various aspects, the chamber  118  is hermetically sealed. 
     Referring to  FIG. 8 , another pump  170  according to certain aspects of the present disclosure is provided. The pump  170  includes a housing  172  and a cover  174 . The housing  172  includes a lip  176 . In a deformed configuration, as shown, the lip  176  cooperates with the cover  174  to at least partially enclose a cavity (not shown) of the housing  172 . 
     Profiles of the cover  174  and the lip  176  in a direction substantially parallel to a surface  178  of the cover  174  may be asymmetric about at least one axis. For example, the profiles of the cover  174  and the lip  176  may be substantially asymmetric about a first axis  180 , and substantially symmetric about a second axis  182  substantially perpendicular to the first axis  180 . More particularly, a first portion  184  may have a first radius of curvature, and a second portion  186  may have a second radius of curvature greater than the first radius of curvature. In various alternative aspects, a lip and cover define other non-circular profiles. 
     The present disclosure also provides a method of roll-forming a noncircular feature, such as a joint. The method is described in the context of the pump  90  of  FIGS. 5-7  and the roll-forming tool  10  of  FIGS. 1-4 . However, one skilled in the art will appreciate that the method may be used to roll-form any feature having a noncircular profile. An example method  210  is depicted in  FIG. 9 . At  212 , the method may include disposing the seal  140  within the groove  116 . After disposing the seal  140  in the groove  116 , at  214 , the cover  94  may be disposed in the cavity  112 . After the cover  94  is placed in the cavity  112 , the roll-forming tool  10  may be used to form the joint  150 , as described in greater detail below. 
     At  216 , the roll-forming tool  10  may be rotated about the fixed longitudinal axis  14 . At  218 , as the roll-forming tool  10  rotates, the first and second rollers  20 ,  22  may be engaged with the noncircular lip  96 . More particularly, the first and second rollers  20 ,  22  of the roll-forming tool  10  may be operably engaged with the top surface  128  of the lip  96  of the housing  92 . At  220 , as the tool  10  rotates about the longitudinal axis  14 , the rollers  20 ,  22  engage the top surface  128  to rotate about the lateral axis  18  of the axle  16 . A load may concurrently be applied to the lip  96  through the tool  10  in the downward direction  122 . As described above, the first and second rollers  20 ,  22  can maintain continuous and concurrent contact with the lip  96  as the longitudinal axis  14  of the tool  10  remains fixed during rotation of the tool  10 . The operable engagement of the rollers  20 ,  22  with the lip  96  causes the lip  96  to deform inward  120  to transition from the undeformed configuration ( FIG. 6 ) to the deformed configuration ( FIG. 7 ). In the deformed configuration, the joint  150  between the lip  96  of the housing  92  and the cover  94  is formed. At  222 , the rollers  20 ,  22  may be disengaged with the lip  96 . 
     Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail. 
     The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed. 
     When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments. 
     Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. 
     The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.