Patent Publication Number: US-2019190114-A1

Title: Polarizer assembly

Description:
RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 62/383,803 filed Sep. 6, 2016, which is hereby incorporated herein by reference. 
    
    
     FIELD OF INVENTION 
     This application relates generally to satellite communications antenna systems and devices, and more particularly to polarizer assemblies for such systems and devices. 
     BACKGROUND 
     Conventional ground based satellite communication antenna systems may include for example an antenna feed horn connected to a transceiver. More specifically, transmit and receive ports of the transceiver are connected to an orthomode transducer (OMT) waveguide device, which includes one or more waveguides. The waveguides of the OMT waveguide device, in turn, are connected to one end of a polarizer assembly. An opposite end of the polarizer assembly is connected to the feed horn antenna. 
     The typical polarizer assembly may include a pair of one part geometry components or be made up of parts having different geometries. Whether the geometric configuration is single or multi part, a gap free continuous seal bead between the first and second components is required for proper signal processing performance by the channel. 
     For some polarizer assemblies, there remain various shortcomings, drawbacks, and disadvantages relative to certain applications. For example, some polarizer assemblies utilize a snap fit assembly wherein tabs or projections on one component snap into slots or grooves in a second component. The problems with such an approach include higher manufacturing costs associated with the two components requiring two unique geometries and insufficient seam line integrity in the channel between the components. Other polarizer assemblies have used thread forming screws to assemble the two components. While this method has proven capable, it is not as cost effective as current die casting versions. Thread forming screws provide good retention capability, however hardware and assembly labor requirements limit cost effectiveness. Another variation for assembly is to use heat staking by converting screw bosses to posts that are staked into ‘rivet heads.’ The heat staking method provides moderate retention capability and is more cost effective than thread forming screws, however the capital equipment cost is very high. There is also some risk due to the heat required to stake parts together; that is, the heat may cause the components to distort. The overall cost is better than die casting, although long cycle times are required for each assembly. 
     Accordingly, there remains a need for further contributions in this area of technology. 
     SUMMARY OF INVENTION 
     The present invention is directed to a polarizer assembly in which projections and openings of a first component are mated with projections and openings of a second component upon relative rotation between the components to an assembled position. The resulting assembled component provides a tight seal bead along edges of channel portions of the first and second components. According to one aspect of the invention, the polarizer assembly includes a first component including a first channel portion extending along a first component axis and having a plurality of first locking projections and/or first openings on opposite sides of the first channel portion; and a second component including a second channel portion extending along a second component axis and having a plurality of second locking projections and/or second openings on opposite sides of the second channel portion. The second component is rotatable relative to the first component about a common rotation axis between a pre-assembled position in which the second component axis is angularly offset from the first component axis, and an assembled position in which the second locking projections and/or second openings mate with the first locking projections and/or first openings and the first and second channel portions form a channel that functions to polarize waveforms. 
     Embodiments of the invention may include one or more of the following additional features separately or in combination. 
     The first and second components may have the same geometry. 
     In the assembled position, the first and second components may be configured to attach to a waveguide at one end and a feed horn at an opposite end, and the common rotation axis may be positioned closer to the waveguide end. 
     The channel may be square at one end and circular at an opposite end. 
     The plurality of first locking projections and/or first openings may be formed in first flanges on opposite sides of the first channel portion, and the plurality of second locking projections and/or second openings may be formed in second flanges on opposite sides of the second channel portion. 
     In the assembled position, the plurality of second locking projections and/or second openings may mate with the plurality of first locking projections and/or first openings to clamp respective edges of the first and second channel portions into an interference fit. 
     The plurality of first locking projections and/or first openings may include a plurality of first tabs and/or slots, and the plurality of second locking projections and/or second openings may include a plurality of second tabs and/or slots. 
     The plurality of first locking projections and/or first openings may be progressively further radially spaced from the common rotation axis, and the plurality of second locking projections and/or second openings may be progressively further radially spaced from the common rotation axis. 
     The first component may include a post that is configured to slide axially into an opening in the second component in the direction of the common rotation axis to align the first and second components along the common rotation axis. 
     The post may have an arc shape and the opening may have an arc shape, and the angular span of the arc shape post may be less than the angular span of the arc shape opening. 
     The arc shape post may be configured to slidably fit into the arc shape opening to angularly offset the second component axis relative to the first component axis and position the first and second components into the pre-assembled position. 
     An inner radius of the post can be configured to slide against an outer radius of a wall of the opening to guide rotational movement of the second component relative to the first component between the pre-assembled position and the assembled position. 
     The plurality of first locking projections and/or first openings may include a wedge shape locking tab, and the plurality of second locking projections and/or second openings may include a wedge shape slot. The wedge shape locking tab may be configured to engage walls of the wedge shape slot as the second component is rotated into the assembled position. 
     The wedge shape locking tab may be formed axially above an undercut in the post that extends circumferentially inward from an edge of an angular span of the post. The wedge shape slot may be formed by a groove that extends circumferentially outward from an edge of an angular span of the opening. 
     The plurality of first locking projections and/or first openings may include locking tabs progressively further radially spaced from the common rotation axis, and the plurality of second locking projections and/or second openings may include slots progressively further radially spaced from the common rotation axis. 
     The progressively further radially spaced slots may open up to an edge of a second flange of the second component and be configured to circumferentially slidably receive the respective progressively further radially spaced locking tabs of the first component as the second component is rotated from the pre-assembled position to the assembled position. 
     The locking tabs may include posts projecting from a first flange face of the first component axially in the direction of the common rotation axis, and at least one projection extending laterally from the post, the projection and first flange face defining therebetween a circumferentially extending guideway within which an edge of the corresponding mating slot moves as the second component is rotated to the assembled position. 
     The at least one laterally extending projection may include a pair of laterally extending projections that project radially toward and radially away from the post, the projections and first flange face defining therebetween circumferentially extending guideways within which opposite edges of the corresponding mating slot move as the second component is rotated to the assembled position. 
     The at least one laterally extending projection of the locking tab furthest from the common rotation axis may project radially from the post. 
     The first component may include a spring actuated tab and the second component may include a mounting hole that receives the spring actuated tab in the assembled position to rotationally lock the second component to the first component. 
     The spring actuated tab may be configured to flex away from the second component as the second component is rotated from the pre-assembled position toward the assembled position, and to flex back toward the second component in the assembled position. 
     The spring actuated tab may include a tab connected to a flexible cantilever arm that in turn is connected to a portion of a flange of the first component, with the flexible cantilever arm being configured to flex as the second component is rotated from the pre-assembled position toward the assembled position. 
     The flexible cantilever arm may include a ramp that the second component slides against to gradually flex the cantilever arm as the second component is rotated from the pre-assembled position toward the assembled position. 
     The flexible cantilever arm may be connected to an outer portion of the first flange and project circumferentially toward the first channel portion. 
     According to another aspect of the invention, a method of assembling a polarizer assembly includes aligning a first component and a second component axially along a common rotation axis. The first component includes a first channel portion extending along a first component axis and having a plurality of first locking projections and/or first openings on opposite sides of the first channel portion. The second component includes a second channel portion extending along a second component axis and having a plurality of second locking projections and/or second openings on opposite sides of the second channel portion. The method includes arranging the first component axis of the first component to be angularly offset about the common rotation axis relative to the second component axis of the second component. The method further includes rotating the second component relative to the first component about the common rotation axis from the pre-assembled position to an assembled position in which the first locking projections and/or first openings mate with the second locking projections and/or second openings and the first and second channel portions form a channel that functions to polarize waveforms. 
     The axially aligning the first and second components along the common rotation axis may include sliding a post of the first component axially into an opening in the second component in the direction of the common rotation axis. 
     As the second component is rotated relative to the first component from the pre-assembled position to the assembled position, edges of the second channel portion may be gradually clamped into an interference fit with edges of the first channel portion. 
     The method may further include flexing a spring actuated tab away from the second component as the second component is rotated from the pre-assembled position toward the assembled position, and flexing the spring actuated tab back toward the second component in the assembled position to rotationally lock the second component to the first component. 
     The following description and the annexed drawings set forth certain illustrative embodiments of the invention. These embodiments are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features according to aspects of the invention will become apparent from the following detailed description when considered in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The annexed drawings, which are not necessarily to scale, show various aspects of the invention. 
         FIG. 1  is a block diagram of a satellite communications antenna system in accordance with the invention. 
         FIG. 2  is a perspective view of a polarizer assembly of the  FIG. 1  antenna system in accordance with the invention, showing first and second components of the polarizer assembly in an assembled state. 
         FIG. 2A  is a cross sectional view of the  FIG. 2  polarizer assembly at a waveguide connection end thereof as viewed from the plane  2 A- 2 A in  FIG. 2 . 
         FIG. 2B  is a cross sectional view of the  FIG. 2  polarizer assembly at a central portion thereof as viewed from the plane  2 B- 2 B in  FIG. 2 . 
         FIG. 2C  is a cross sectional view of the  FIG. 2  polarizer assembly at a feed horn connection end thereof as viewed from the plane  2 C- 2 C in  FIG. 2 . 
         FIG. 3  is an exploded perspective view of the  FIG. 2  polarizer assembly. 
         FIG. 4  is a top plan view of the polarizer assembly in a pre-assembled state, showing first and second components stacked over each other aligned over a center of rotation axis. 
         FIG. 5  is an enlarged perspective view of a portion of the polarizer assembly in a pre-assembled state, showing a locking tab and slot of a locking mechanism in an unengaged state. 
         FIG. 6  is an enlarged perspective view of a portion of the polarizer assembly in an assembled state, showing the locking tab and slot of the locking mechanism in an engaged state. 
         FIG. 7  is an enlarged perspective view of a portion of the polarizer assembly in a pre-assembled state, showing locking tabs of one component and mating slots of an opposite component, and showing a snap locking mechanism of the components in an unengaged state. 
         FIG. 8  is an enlarged perspective view of a portion of the polarizer assembly in an assembled state, showing a locking tab of one component mated with a slot of an opposite component. 
         FIG. 9  is an enlarged perspective view of a portion of the polarizer assembly in an assembled state, showing a locking tab of one component mated with a slot of an opposite component. 
         FIG. 10  is an enlarged perspective view of a portion of a component of the polarizer assembly, showing a tab of the snap locking mechanism. 
         FIG. 11  is an enlarged perspective view of a portion of a component of the polarizer assembly, showing a mounting hole of the snap locking mechanism. 
         FIG. 12  is an enlarged perspective view of a portion of the polarizer assembly in a pre-assembled state, showing the tab of one component starting to engage an edge of an opposite component as the components are assembled together. 
         FIG. 13  is a cross-section view of a portion of the polarizer assembly in an assembled state, showing a tab of one component engaged with a mounting hole of an opposite component, and showing a locking tab of one component mated with a slot of an opposite component. 
         FIG. 14A  is a cross sectional view of a first component of the polarizer assembly at a waveguide connection end thereof as viewed from the plane  14 A- 14 A in  FIG. 3 . 
         FIG. 14B  is a cross sectional view of the first component of the polarizer assembly at a central portion thereof as viewed from the plane  14 B- 14 B in  FIG. 3 . 
         FIG. 15  is a flowchart of a method of assembling a polarizer assembly in accordance with the invention. 
     
    
    
     DETAILED DESCRIPTION 
     While the present invention can take many different forms, for the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications of the described embodiments, and any further applications of the principles of the invention as described herein, are contemplated as would normally occur to one skilled in the art to which the invention relates. 
       FIGS. 1-4  show a satellite communications antenna system  10  and a polarizer assembly  12  thereof in accordance with the invention. The satellite communications antenna system  10  is merely an example application of the polarizer assembly  12 , and the polarizer assembly  12  can be used in any electronics application for which microwave radio frequency (RF) signal shaping and filtering is desired. As shown in  FIGS. 2-4 , the polarizer assembly  12  may include first and second “clamshell” components  20 ,  22 . The first component  20  may include a first channel portion  30  extending along a first component axis A-A and have a plurality of first locking projections and/or first openings  100   a ,  100   b  on opposite sides of the first channel portion  30 . Similarly, the second component  22  may include a second channel portion  32  extending along a second component axis B-B and have a plurality of second locking projections and/or second openings  102   a ,  102   b  on opposite sides of the second channel portion  32 . As will be described in greater detail below, the second component  22  may be rotatable relative to the first component  20  about a common rotation axis C-C between a pre-assembled position shown in  FIG. 4  in which the second component axis B-B is angularly offset from the first component axis A-A, and an assembled position shown in  FIG. 2  in which the second locking projections and/or second openings  102   a ,  102   b  mate with the first locking projections and/or first openings  100   a ,  100   b , and the first and second channel portions  30 ,  32  form a channel  34 . The channel  34  functions to polarize waveforms, for example, from a waveguide to a feed horn  64  of the satellite communications antenna system  10 . As shown in  FIGS. 2A-2C , the first and second projections and openings  100   a ,  100   b ,  102   a ,  102   b  form a tight seal bead along edges  50 ,  52  of the respective first and second channel portions  30 ,  32 , and clamp in face to face relation the flange faces  46   a ,  46   b ,  48   a ,  48   b  from the contact regions  50 ,  52  to the outer edges  70   a ,  70   b ,  72   a ,  72   b  of the first and second components  20 ,  22 , and, owing to this clamping effect, the first and second projections and openings  100   a ,  100   b ,  102   a ,  102   b  maintain seam line integrity once the first and second components  20 ,  22  are in the assembled position. 
     Referring to  FIG. 1 , the satellite communications antenna system  10  may include an antenna feed horn  64  connected to a transceiver  74 . Transmit and receive ports  76 ,  78  of the transceiver  74  may be connected to an orthomode transducer (OMT) waveguide device  84 . The OMT waveguide device  84  may include one or more waveguides. The waveguides of the OMT waveguide device  84 , in turn, may be connected to one end  88 , also referred to herein as a waveguide connection end  88 , of the polarizer assembly  12 . An opposite end  90  of the polarizer assembly  12 , also referred to herein as a feed horn connection end  90 , may be connected to the feed horn antenna  64 . As shown in  FIGS. 2A and 2C , respectively, the channel  34  of the polarizer assembly  12  is square at the waveguide end  88  and circular at the opposite feed horn end  90 , while the central portion is also square but angularly offset by 45 degrees relative to the waveguide end  88 . The polarizer assembly  12  may be configured to align the input of many divergent wave orientations within target frequencies into polarized horizontal and/or vertical waveforms. Thus, for example, the channel  34 , or central passageway, of the polarizer assembly  12  may be configured to convert linearly polarized signals to circular polarized signals and/or vice versa. Of course, other configurations and types of polarizer assemblies are also contemplated. Moreover, it will be apparent to those skilled in the art that the present invention relates to a bead seal for any two piece or other multi-piece radio frequency (RF) filtering device and, while herein the RF filtering device is described in terms of a polarizer assembly  12 , it will be understood that the polarizer assembly  12  is only one application of the invention and is in no way limiting to the invention. The invention can be used for any multi-piece construction of a polarizer, waveguide, or any other radio frequency filtering assembly, including clamshell and non-clamshell configurations. 
     The polarizer assembly  12  may be constructed of metal, such as zinc die cast material, or metal coated thermoplastic injection molded material. In one embodiment, the components  20 ,  22  are made of a PC-ABS thermoplastic (polycarbonate/acrylonitrile butadiene styrene), cleaned, and then etched with a copper layer, for example, a layer of about 4 microns. The metal layer can be etched on the entire thermoplastic surface of the components  20 ,  22  or merely on the functional surfaces such as the inside surfaces of the channel portions  30 ,  32  and at the seal bead and flange faces  46   a ,  46   b ,  48   a ,  48   b  of respective flanges  40   a ,  40   b ,  42   a ,  42   b  of the first and second components  20 ,  22 . Of course, other types of materials and manufacturing methods are also contemplated. 
     Referring now to  FIGS. 2-4 , the illustrative polarizer assembly  12  may be made up of a pair of one part geometry components; that is, the first and second components  20 ,  22  may have identical geometries. One part geometries can reduce the cost of manufacture as compared to polarizer assemblies that consist of mated components having different geometries. The projections and openings  100   a  of the left flange  40   a  and projections and openings  100   b  of the right flange  40   b  of the first component  20  may be configured to slidably engage with the respective projections and openings  102   b  of the right flange  42   b  and projections and openings  102   a  of the left flange  42   a  of the second component  22 . The projections may take the form of any one or more of tabs, plugs, posts, nubs, protrusions, etc. and the openings may take the form of any one or more of holes, slots, cavities, recesses, etc. For example, the plurality of first locking projections and/or first openings  100   a ,  100   b  may include a plurality of first tabs and/or slots, and the plurality of second locking projections and/or second openings  102   a ,  102   b  may include a plurality of second tabs and/or slots, where the second tabs mate with the first slots and the second slots mate with the first tabs. In the embodiment of  FIG. 3 , the left flange  40   a  of the first component  20  has an opening  110   a , five T-shape tabs  120   a , an L-shape tab  130   a , and a spring actuated tab  140   a , while the right flange  42   b  of the opposite mating second component  22  has a tab  112   b  that mates with the corresponding opening  110   a , five slots  122   b  that mate with the corresponding T-shape tabs  120   a , a slot  132   b  that mates with the corresponding L-shape tab  130   a , and a mounting hole  142   b  that mates with the spring actuated tab  140   a . Similarly, the left flange  42   a  of the second component  22  has an opening  112   a , five T-shape tabs  122   a , an L-shape tab  132   a , and a spring actuated tab  142   a , while the right flange  40   b  of the opposite mating first component  20  has a tab  110   b  that mates with the corresponding opening  112   a , five slots  120   b  that mate with the corresponding T-shape tabs  122   a , a slot  130   b  that mates with the corresponding L-shape tab  132   a , and a mounting hole  140   b  that mates with the spring actuated tab  142   a.    
     The first locking projections and/or first openings  100   a ,  100   b  of the first component  20  and the second locking projections and/or second openings  102   a ,  102   b  of the second component  22  may be configured to sweep, or rotate, about the same center of rotation axis C-C, also referred to herein as a common rotation axis C-C. The first locking projections and/or first openings  100   a ,  100   b  may be progressively further radially spaced from the common rotation axis C-C, and the second locking projections and/or second openings  102   a ,  102   b  may be progressively further radially spaced from the common rotation axis C-C. The male features of one component and the female features of an opposing component may be on radial positions (relative to the common rotation axis C-C) that are aligned with each other. Thus, as shown in  FIGS. 3 and 4 , the tabs  110   b ,  112   b  may be the same radial distance from the axis C-C as the openings  110   a ,  112   a ; the tabs  120   a ,  122   a  may be the same radial distance from the axis C-C as the slots  120   b ,  122   b ; the tabs  130   a ,  132   a  may be the same radial distance from the axis C-C as the slots  130   b ,  132   b ; and the tabs  140   a ,  142   a  may be the same radial distance from the axis C-C as the mounting holes  142   a ,  142   b . When the second component  22  is flipped in a clamshell manner 180 degrees about its second component axis B-B as shown in  FIGS. 3 and 4 , and then set on top of the first component  20  and aligned with the first component  20  along the common rotation axis C-C, and the second component axis B-B is arranged angularly offset by an angle  188  from the first component axis A-A as shown in  FIG. 4 , the components  20 ,  22  are in a pre-assembled position in which the projections and openings  102   b ,  102   a  of one component  22  are ready to be mated to the respective openings and projections  100   a ,  100   b  of the opposing component  20 . In the pre-assembled position of the illustrative embodiment, the angular offset  188  between the first component axis A-A and the second component axis B-B is about 8.0 degrees. The spring actuated tabs  140   a ,  142   a  and mating mounting holes  140   b ,  142   b  of the first and second projections and openings  100   a ,  100   b ,  102   a ,  102   b  may be at opposite axial ends of the components  20 ,  22  as shown in  FIGS. 3 and 4 . As will be described in greater detail below, the spring actuated tabs  140   a ,  142   a  and mounting holes  140   b ,  142   b , when mated, may be configured to aid in rotationally locking the components  20 ,  22  and/or properly axially and transversely aligning the components  20 ,  22 . As shown in  FIG. 2 , the flanges  40   a ,  40   b ,  42   a ,  42   b  may also be provided with axially spaced gussets or ribs  136  between the projection and opening locations to strengthen the components  20 ,  22  and prevent over flexing of the flanges  40   a ,  40   b ,  42   a ,  42   b  or buckling of the flanges  40   a ,  40   b ,  42   a ,  42   b  around the projections and openings during assembly. 
     In the illustrative embodiment, the first and second components  20 ,  22  are one part geometry components, and thus the projections and openings  100   a  on the left flange  40   a  of the first component  20  are identical to the projections and openings  102   a  of the left flange  42   a  of the second component  22 , and the projections and openings  100   b  on the right flange  40   b  of the first component  20  are identical to the projections and openings  102   b  of the right flange  42   b  of the second component  22 . As will be appreciated by those skilled in the art, the first and second components  20 ,  22  need not be limited to one part geometries and the means for clamping and/or fastening the first and second components  20 ,  22  need not be limited to the projections and openings  100   a ,  100   b ,  102   a ,  102   b  or have the arrangement of the projections and openings  100   a ,  100   b ,  102   a ,  102   b  shown in the figures. The first and second components  20 ,  22  may have different geometries. For example, the left and right flanges of the first component  20  may be fitted with all projections while the left and right flanges of the second component  22  are configured with corresponding mating openings. In another form, assembling may alternately or additionally be by fastening, for example thread forming screws that engage pilot holes in the flanges  40   a ,  40   b ,  42   a ,  42   b , or machine bolts that pass through holes in the flanges  40   a ,  40   b ,  42   a ,  42   b  and are secured by nuts to form bolted joints along the flanges  40   a ,  40   b ,  42   a ,  42   b . The left and right flanges of the first component  20  may be fitted with bosses and pilot holes while the left and right flanges of the second component  22  are configured with through holes. In yet another form, heat staking may be used, whereby for example plastic or metal posts on the first flange are inserted into corresponding boss holes in the opposing flange, followed by swaging the material at the top of the posts to form a “rivet” head that clamps down on the bosses to secure the flanges together. One or more external clamps, for example binder clips, can also or alternately be used to secure the flanges together. The first and second components  20 ,  22  may also or alternatively be clamped together by means of projections in one component locking and mating with openings in the opposite component, where the projections may be in the form of one or more of tabs, plugs, posts, nubs, protrusions, among others, and the openings may take the form of any one or more of holes, slots, cavities, recesses, among others. The first component may include thread forming screws that engage “unthreaded bosses” in the opposing second component. The first component may include standard screws passed through openings in the first component, with nuts on the opposite half of the screw head half at the second component. Standard rivets that are “headed” may also or alternatively be used to retain clamped closure of the first and second components when they are assembled. Snap fit tabs may also or alternatively be used, whereby for example tabs in the first component flex during assembly of the first component to the second component and, once in an assembled position, snap back into an opening in the second component to lock the first and second components in the assembled position. In one form, the snap fit tabs may be “snap barbs” in the first component and “snap barb receptacles” in the opposite facing second component. The assembling could also use any combination of the foregoing, such as by clamping  110   a ,  110   b ,  112   a ,  112   b  and rotational locking  140   a ,  140   b ,  142   a ,  142   b  at the axially opposite ends of the flanges  40   a ,  40   b ,  42   a ,  42   b , and fasteners at the axially central portion of the flanges  40   a ,  40   b ,  42   a ,  42   b . In another alternative combination, the fastening and/or clamping could incorporate clamping at the axially opposite ends of the flanges, and thread forming screws at the axially central portion of the flanges. Of course, other configurations and fastening methods may also or alternately be employed, as will be appreciated. 
     Reference is now made to  FIGS. 5-13 , which show greater detail of the projections and openings  100   a ,  100   b ,  102   a ,  102   b  of the first and second components  20 ,  22  and the engagements that take place in the mating of the projections and openings  100   a ,  100   b ,  102   a ,  102   b  as the components  20 ,  22  are assembled from the pre-assembled position of  FIG. 4  to the assembled position of  FIG. 2 . 
       FIGS. 5 and 6  show a locking mechanism  200  that axially and rotationally locks the second component  22  to the first component  20  of the polarizer assembly  12 . The locking mechanism  200  includes the locking tab  110   b  of the first component  20  and the mating slot  112   a  of the second component  22 .  FIG. 5  shows the locking mechanism  200  in a pre-assembled position in which the locking tab  110   b  and mating slot  112   a  are not engaged, while  FIGS. 2 and 6  show the locking mechanism  200  (two locking mechanisms  200  in  FIG. 2 ) in an assembled position in which the locking tab  110   b  and mating slot  112   a  are engaged. 
     The locking mechanism  200  may include a post  210  that projects upward from the flange face  46   b  of the flange  40   b  of the first component  20  and an opening  212  that extends axially through the flange  42   a  of the second component  22 . The post  210  may be configured to slide axially into the opening  212  in the direction of the common rotation axis C-C to align the first and second components  20 ,  22  along the common rotation axis C-C. The post  210  and the opening  212  may each have an arc shape. The angular span  216  of the arc shape post  210  may be slightly less than the angular span  218  of the arc shape opening  212 . As shown in  FIG. 4 , the arc shape post  210  is configured to axially slidably fit into the arc shape opening  212  to angularly offset the second component axis B-B relative to the first component axis A-A by the angle  188  to thereby position the first and second components  20 ,  22  into the pre-assembled position. In addition, an inner radius  226  of the post  210  may be configured to slide against an outer radius  228  of a wall of the opening  212  to guide rotational movement of the second component  22  relative to the first component  20  between the pre-assembled position and the assembled position. In the illustrative embodiment, the angular offset  188  is about 8.0 degrees, although it will be appreciated that other angles may be suitable depending on for example the flange sizes of the components  20 ,  22 , and the appropriate proximity of the locking mechanisms  200  to the edges  50 ,  52  of the first and second channel portions  30 ,  32  to effect a proper bead seal. 
     As noted above, the plurality of first locking projections and/or first openings  100   a ,  100   b  may include the locking tab  110   b , and the plurality of second locking projections and/or second openings  102   a ,  102   b  may include the mating slot  112   a . In the  FIG. 5  locking mechanism  200 , the locking tab  110   b  has a wedge shape that corresponds to a wedge shape of the mating slot  112   a . The wedge shape locking tab  110   b  may be formed axially above an undercut  240  in the post  210  that extends circumferentially inward from an edge  244  of the angular span  216  of the post  210 . The wedge shape slot  112   a  may be formed by a circumferentially extending groove  250  that extends circumferentially outward from an edge  254  of the angular span  218  of the opening  212 . For the slot  112   a , the wedge shape may be formed by a relatively wider front portion  264  and a relatively narrower back portion  268  and extend circumferentially about the common rotation axis C-C about 8.0 degrees. For the locking tab  110   b , the wedge shape may have a relatively narrower front portion at  278  that is the same in width as that of the relatively narrower back portion  268  of the slot  112   b , and a relatively wider back portion at  274  that is the same in width as that of the relatively wider front portion  264  of the slot  112   b . The wedge shape locking tab  110   b  likewise may extend about the common rotation axis C-C about 8.0 degrees. The wedge shape locking tab  110   b  may be configured to engage walls  280  of the wedge shape slot  112   a  as the second component  22  is rotated from the pre-assembled position of  FIG. 5  into the assembled position shown in  FIG. 6 . 
     As shown in  FIGS. 4-6 , when assembling the second component  22  to the first component  20 , the second component  22  is rotated counterclockwise relative to the first component  20 . During assembly, the tabs  110   b ,  112   b  snugly fit into the respective slots  112   a ,  110   a . The mating of the tabs  110   b ,  112   b  with the slots  112   a ,  110   a  prevents further counterclockwise movement of the second component  22  relative to the first component  20 . In this regard, the tabs  110   b ,  112   b  and slots  112   a ,  110   a  provide a rotational locking feature. As will be described in greater detail below, the mating of the tabs  110   b ,  112   b  into the respective slots  112   a ,  110   a , in combination with the mating of the spring actuated tabs  140   a ,  142   a  into the respective mounting holes  142   b ,  140   b , rotationally locks the components  20 ,  22  together, that is, prevents relative counterclockwise or clockwise rotation between the first and second components. 
     The locking mechanism  200  may also be configured to axially lock the components  20 ,  22  together. The axial locking can be by way of merely seating the wedge shape locking tabs  110   b ,  112   b  into the respective wedge shape slots  112   a ,  110   a  such that the undersides of the tabs  110   b ,  112   b  slidingly abut the base walls of the respective wedge shape slots  112   a ,  110   a . Alternatively, axial locking can be by way of an interference fit created between the wedge shape locking tabs  110   b ,  112   b  and the respective wedge shape slots  112   a ,  110   a . Referring to  FIG. 5 , one way to create an axial interference fit between the wedge shape locking tab  110   b  and the wedge shape slot  112   a , is to configure the axial height from the flange face  46   b  of the first component  20  to the underside of the wedge shape locking tab  110   b  to be less than the axial height from the flange face  48   a  of the second component  22  to the base wall of the wedge shape slot  112   a . This interference fit axially clamps the second component  22  to the first component  20  and maintains the clamping force in the assembled position. As shown in  FIG. 2 , a locking mechanism  200  may be located on both sides of the channel  34 . By seating or interference fitting the wedge shape locking tabs  110   b ,  112   b  to the respective wedge shape slots  112   a ,  110   a , the components  20 ,  22  can be axially locked. 
     In the illustrative embodiment, the locking mechanisms  200  are located at the end  88  where the polarizer assembly  12  connects to the waveguides of the OMT waveguide device  84  of the satellite communications antenna system  10 . As will be appreciated, the locking mechanisms  200  need not be limited to such location. For example, the locking mechanisms  200  may additionally or alternately be located at the end  90  where the polarizer assembly  12  connects to the feed horn  64 . The locking mechanisms  200  may be located anywhere along the flanges  40   a ,  40   b ,  42   a ,  42   b  of the first and second components  20 ,  22 . 
     Referring again to  FIGS. 3 and 4 , the plurality of first locking projections and/or first openings  100   a ,  100   b  may include a plurality of locking tabs  120   a ,  130   a  on the first flange  40   a  of the first component  20  that are progressively further radially spaced from the common rotation axis C-C. Similarly, the plurality of second locking projections and/or second openings  102   a ,  102   b  may include a plurality of slots  122   b ,  132   b  on the second flange  42   b  of the second component  22  that are progressively further radially spaced from the common rotation axis C-C. The locking tabs  120   a ,  130   a  may be configured to gradually engage the opposite mating slots  122   b ,  132   b  as the second component  22  is rotated from the pre-assembled position shown in  FIG. 4  to the assembled position shown in  FIG. 2 . Once assembled, the engaged tabs  120   a ,  130   a  and mating slots  122   b ,  132   b  provide face to face retention between the flange faces  46   b ,  48   a  of the respective first and second components  20 ,  22 . 
       FIGS. 7-9  show greater detail of the locking tabs  120   a ,  130   a  and the mating slots  122   b ,  132   b . The slots  122   b ,  132   b  open up to an edge  300  of the second flange  42   b  of the second component  22  and are configured to circumferentially slidably receive the respective locking tabs  120   a ,  130   a  of the first component  20  as the second component  22  is rotated from the pre-assembled position to the assembled position. The locking tabs  120   a ,  130   a  may include posts  310  projecting from the first flange face  46   a  of the first component  20  in the direction of the common rotation axis C-C, and at least one projection  324  extending laterally from the post  310 , in the illustrative embodiment extending radially relative to the common rotation axis C-C. In the illustrative embodiment, the locking tab  130   a  that is furthest from the common rotation axis C-C, which is more clearly shown in  FIGS. 7 and 9 , includes one projection  324 . As such, the locking tab  130   a  is also referred to herein as an L-shape locking tab  130   a . The projection  324  and first flange face  46   a  may define therebetween a circumferentially extending guideway  326  within which an edge  328  of the corresponding mating slot  132   b  can move as the second component  22  is rotated to the assembled position. In the illustrative embodiment, the locking tabs  120   a , which are more clearly shown in  FIGS. 7 and 8 , include a pair of laterally extending projections  324  that project radially toward and radially away from the post  310 . As such, the locking tabs  120   a  are also referred to herein as T-shape locking tabs  120   a . The projections  324  and first flange face  46   a  may define therebetween circumferentially extending guideways  336  within which opposite edges  338  of the corresponding mating slots  122   b  can move as the second component  22  is rotated to the assembled position. 
     The locking tabs  120   a ,  130   a ,  122   a ,  132   a  and respective mating slots  122   b ,  132   b ,  120   b ,  130   b  may be configured to axially lock the components  20 ,  22  together. The axial locking can be by way of merely sliding the locking tabs  120   a ,  130   a ,  122   a ,  132   a  into the respective mating slots  122   b ,  132   b ,  120   b ,  130   b  such that the upper and lower walls of the guideways  326 ,  336  of the locking tabs  120   a ,  130   a ,  122   a ,  132   a , which correspond respectively to the undersides of the projections  324  and the portions of the flange faces  46   a ,  48   a  opposite thereto, slidingly abut the respective upper and lower walls of the edges  328 ,  338  of the slots  122   b ,  132   b ,  120   b ,  130   b , which correspond to the upper and lower surface portions of the flanges  40   b ,  42   b  adjacent the slots  122   b ,  132   b ,  120   b ,  130   b . Alternatively, axial locking can be by way of an interference fit created between the locking tabs  120   a ,  130   a ,  122   a ,  132   a  and the respective mating slots  122   b ,  132   b ,  120   b ,  130   b . Referring to  FIG. 7 , one way to create an axial interference fit between the locking tabs  120   a ,  130   a ,  122   a ,  132   a  and the slots  122   b ,  132   b ,  120   b ,  130   b , is to configure the axial height of the guideways  326 ,  336  to be less than the axial height of the edges  328 ,  338  of the slots  122   b ,  132   b ,  120   b ,  130   b . This interference fit axially clamps the second component  22  to the first component  20  and maintains the clamping force in the assembled position. As shown in  FIGS. 2 and 3 , the locking tabs  120   a ,  130   a ,  122   a ,  132   a  and respective mating slots  122   b ,  132   b ,  120   b ,  130   b  may be located on both sides of the channel  34 . By sliding or interference fitting the locking tabs  120   a ,  130   a ,  122   a ,  132   a  to the respective slots  122   b ,  132   b ,  120   b ,  130   b , the components  20 ,  22  can be axially locked. 
       FIGS. 2, 4, 7 and 10-13  show details of a snap locking mechanism  400  that rotationally locks the second component  22  to the first component  20  of the polarizer assembly  12 . The snap locking mechanism  400  may include the spring actuated tab  140   a  of the first component  20  and the mounting hole  142   b  of the second component  22 .  FIGS. 4 and 7  show the snap locking mechanism  400  in a pre-assembled position in which the spring actuated tab  140   a  and mounting hole  142   b  are not engaged, while  FIGS. 2 and 13  show the snap locking mechanism  400  (two snap locking mechanisms  400  in  FIG. 2 ) in an assembled position in which the spring actuated tab  140   a  is received in and engaged with the mounting hole  142   b  to rotationally lock the second component  22  to the first component  20 . In one form, the snap locking mechanism  400  is configured to lock the second component  22  to the first component  20  when proper alignment of the first and second components  20 ,  22  is achieved. 
     The spring actuated tab  140   a  may be configured to flex away from the second component  22  as the second component  22  is rotated from the pre-assembled position of  FIG. 4  toward the assembled position of  FIG. 2 , and to flex back toward the second component  22  in the assembled position. As shown in  FIGS. 10 and 12 , the spring actuated tab  140   a  may include a tab  410  connected to a flexible cantilever arm  414 . The flexible cantilever arm  414 , in turn, may be connected to an outer portion  418  of the first flange  40   a  of the first component  20  and project circumferentially toward the first channel portion  30  (see  FIG. 3 ). The flexible cantilever arm  414  may be configured to flex as the second component  22  is rotated from the pre-assembled position toward the assembled position. 
       FIG. 12  shows one way by which the flexure may be realized. In  FIG. 12 , the flexible cantilever arm  414  includes a ramp  426  that the second component  22  slides against to gradually flex the cantilever arm  414  as the second component  22  is rotated from the pre-assembled position toward the assembled position. The ramp  426  may extend circumferentially relative to the common rotation axis C-C in a direction opposite that of where the cantilever arm  414  connects to the outer portion  418  of the first flange  40   a . As the second component  22  is rotated relative to the first component  20 , the ramp  426  engages the edge  300  of the flange  42   b  of the second component  22 , and then the edge  300  of the second component  22  drives the ramp  426  axially downward, that is, axially away from the second component  22 . It will be appreciated that the flexible cantilever arm  414  can be connected to the first component  20  at a connection point other than the outer portion  418  of the first flange  40   a . For example, the flexible cantilever arm  414  can be connected to an inner portion  424  of the first flange  40   a  of the first component  20  and project circumferentially toward the outer edge  70   a  of the first flange  40   a , in which case the ramp  426  may form the cantilever arm  414  with the tab  410  being located at a distal free end of the ramp  426 . 
       FIGS. 11 and 13  show the mounting hole  142   b  side of the snap locking mechanism  400 . The mounting hole  142   b  may be formed as a hole, slot, cavity, recess, etc. in the second flange  42   b  of the second component  22 . The depth of the mounting hole  142   b  below the flange face  48   b  of the second flange  42   b  enables the tab  410  of the spring actuated tab  140   a  to drop into the mounting hole  142   b  when the second component  22  reaches the rotational position achieved in the assembled position of  FIG. 2 . In the illustrative embodiment, the tab  410  and mounting hole  142   b  are round shape, and the circumference of the tab  410  is slightly less in size than the circumference of the mounting hole  142   b  to enable the tab  410  to slidably fit into the mounting hole  142   b . As will be appreciated, the spring constant associated with the cantilever arm  414  of the spring actuated tab  140   a  can be selected to urge the tab  410  into the mounting hole  142   b . For relatively greater clearance between the tab  410  and mounting hole  142   b  the spring constant can be designed to be relatively less, while for relatively less clearance between the tab  410  and mounting hole  142   b  the spring constant can be designed to be relatively greater.  FIG. 13  shows the tab  410  of the spring actuated tab  140   a  fully engaged into the mounting hole  142   b . As shown in  FIG. 13 , when the spring actuated tab  140   a  fits into the mounting hole  142   b , the tab  410  thereof need not reach the bottom  448  of the mounting hole  142   b . Of course, the tab  410  and mounting hole  142   b  can also be configured such that the periphery of the tab  410  engages the inner periphery of the mounting hole  142   b  before (or when) the tab  410  reaches its unflexed position. Further, to facilitate centering of the tab  410  into the mounting hole  142   b , and thus further aiding in rotationally and axially aligning the first and second components  20 ,  22  together in the assembled position, the tab  410  and/or mounting hole  142   b  may be tapered. Referring to  FIG. 13 , the mounting hole  142   b  can taper, for example, as it extends axially from the flange face  48   b  to its bottom  448 , and the tab  410  can taper, for example, as it extends axially from its bottom  450  to its top  452 . 
     The snap locking mechanism  400  may also provide a clearance slot  456  that corresponds in position to the ramp  426  of the spring actuated tab  140   a  when the first and second components  20 ,  22  are in the assembled position. Thus, referring to  FIG. 11 , the clearance slot  456  may extend circumferentially relative to the common rotation axis C-C in a direction opposite that of the edge  300  of the second flange  42   b  of the second component  22 . The depth of the clearance slot  456  below the flange face  48   b  of the second flange  42   b  enables the ramp  426  of the spring actuated tab  140   a  to drop into the clearance slot  456  when the second component  22  reaches the full rotational position achieved in the assembled position of  FIG. 2 . The clearance slot  456  receives the ramp  426  so that the cantilever arm  414  is not held in the flexed position when the tab  410  drops into the mounting hole  142   b.    
     Once the second component  22  is assembled to the first component  20 , and the tab  410  and ramp  426  have dropped or been urged into the respective mounting hole  142   b  and clearance slot  456 , the side  460  ( FIGS. 10 and 13 ) of the tab  410  facing a direction opposite that of the rotational direction for assembling the components  20 ,  22 , which in the illustrative embodiment is also the side  460  of the tab  410  opposite that of the ramp  426 , abuts an opposing surface  462  ( FIGS. 11 and 13 ) of the mounting hole  142   b . As shown in  FIGS. 4 and 10-13 , when assembling the second component  22  to the first component  20 , the second component  22  is rotated counterclockwise relative to the first component  20 . In the assembled position, with the tabs  410  of the spring actuated tabs  140   a ,  142   a  snugly fit into the respective mounting holes  142   b ,  140   b , the side  460  of the tab  410  abuts the side  462  of the mounting hole  142   b ,  140   b  to prevent the second component  22  from reverse rotating relative to the first component  20 , that is, to prevent the second component  22  from rotating clockwise relative to the first component  20 . In this regard, the spring actuated tabs  140   a ,  142   a  and mounting holes  142   b ,  140   b  provide a rotational locking feature. The mating of the spring actuated tabs  140   a ,  142   a  into the respective mounting holes  142   b ,  140   b , in combination with the mating of the tabs  110   b ,  112   b  into the respective slots  112   a ,  110   a , rotationally locks the components  20 ,  22  together, that is, prevents relative counterclockwise or clockwise rotation between the first and second components  20 ,  22 . 
     In the illustrative embodiment, the snap locking mechanisms  400  are located at the end  90  where the polarizer assembly  12  connects to the feed horn  64  of the satellite communications antenna system  10 . As will be appreciated, the snap locking mechanisms  400  need not be limited to such location. For example, the snap locking mechanisms  400  may additionally or alternately be located at the end  88  where the polarizer assembly  12  connects to the waveguides of the OMT waveguide device  84 . The snap locking mechanisms  400  may be located anywhere along the flanges  40   a ,  40   b ,  42   a ,  42   b  of the first and second components  20 ,  22 . 
     In addition, the spring actuated tabs  140   a  of the snap locking mechanisms  400  are described as having flexible cantilever arms  414  to realize their spring biased actuation. It will be appreciated that any spring means may be used to realize the spring biased actuation. For example, the cantilever arm  414  can be omitted and the tab  410  can instead form a distal end of a spring plunger installed into a push-fit hole in the first component  20 . In this configuration, the spring loaded tab  410  depresses against the load of the spring plunger as the edge  300  of the second component  22  urges the ramp  426  downward as the second component  22  is rotated relative to the first component  20  from the pre-assembled position toward the assembled position. Once the second component  22  reaches the assembled position, the spring loaded tab  410  of the first component  20  then snaps into the mounting hole  142   b  in the second component  22  to rotationally lock the components  20 ,  22 . In another form, the spring actuated tab  140   a  may take the form of a nub or protrusion on a flange of the first component  20  and a corresponding cavity or recess in the second component  22 . In this configuration, the flanges of the first and second components  20 ,  22  may be configured to deflect away from each other due to the nub urging the flanges apart as the second component  22  is rotated relative to the first component  20  from the pre-assembled position toward the assembled position. Once the second component  22  reaches the assembled position, the nub then snaps into the corresponding cavity of the second component  22 , causing the flanges to flex toward each other, and the engagement of the nub and cavity rotationally locking the components  20 ,  22 . 
     In the above, the tabs  410  and mounting holes  142   b  are shown and described as having a round shape. It will be appreciated that shapes other than round are also contemplated, so long as the tab  410  and mounting hole  142   b  provide respective abutting surfaces  460  and  462  (round or otherwise) that contact one another to prevent reverse rotation of the second component  22  relative to the first component  20  once the second component  22  has reached the assembled position shown in  FIG. 2 . For example, the tab  410  and mounting hole  142   b  may have a square shape, or a flat top pyramid shape, among others. 
     The polarizer assembly  12  is described as including a pair of snap locking mechanisms  400  at the feed horn connection end  90  and a pair of locking mechanisms  200  at the waveguide connection end  88 . Referring to  FIG. 4 , the locking mechanisms  200  prevent further counterclockwise rotation of the second component  22  relative to the first component  20  once the second component  22  has reached the assembled position shown in  FIG. 2 , where for example the wedge shape locking tabs  110   b ,  112   b  seat in, or interference fit with, the respective wedge shape slots  112   a ,  110   a  as shown in  FIGS. 5 and 6 . The snap locking mechanisms  400  prevent reverse rotation (clockwise rotation in  FIG. 4 ) of the second component  22  relative to the first component  20  once the second component  22  has reached the assembled position shown in  FIG. 2 , where for example the tabs  410  seat in the respective mounting holes  142   b  as shown in  FIG. 13 . The polarizer assembly  12  need not be limited to such configuration and other embodiments are contemplated. In one form, for example, a single locking mechanism  200  may be provided at the waveguide connection end  88  and a single snap locking mechanism  400  at the feed horn connection end  90 . The single locking mechanism  200  and single snap locking mechanism  400  can be on opposite sides of the channel  34 , or both on one side of the channel  34 . In another form, the locking mechanism  200  may be located at the same end, whether the waveguide connection end  88  or the feed horn connection end  90 , as the snap locking mechanism  400 . 
     Referring now to  FIGS. 14A and 14B , there are shown cross sections of the first component  20 , shown in  FIG. 3 , at the waveguide connection end  88  and central portion thereof, respectively. The first flanges  40   a ,  40   b  of the first component  20  may be configured to create an interference fit between the edges  50  of the first channel portion  30  and the corresponding edges  52  of the opposing second channel portion  32  when the first and second components  20 ,  22  are assembled together as shown in  FIG. 2 , and in cross section in  FIGS. 2A-2C . In  FIG. 14A , the interference fit is obtained by the first flanges  40   a ,  40   b  being sloped at  500  about 0.5 to 3.5 degrees relative to horizontal from the edges  50  of the first channel portion  30  to the outer edges  70   a ,  70   b  of the first flanges  40   a ,  40   b .  FIG. 2A  shows the first flanges  40   a ,  40   b  in the horizontal position at the waveguide connection end  88  of the polarizer assembly  12 . As shown in  FIG. 14B , the interference fit can be obtained by the first flanges  40   a ,  40   b  being sloped at  500  about 0.5 to 3.5 degrees relative to horizontal from the edges  50  of the first channel portion  30  to a clamping centerline  116 ,  118  of the respective first flanges  40   a ,  40   b , and then horizontal at a portion  506  from the clamping centerline  116 ,  118  outward to the outer edges  70   a ,  70   b  of the first flanges  40   a ,  40   b .  FIG. 2B  shows the first flanges  40   a ,  40   b  in the horizontal position at the central portion of the polarizer assembly  12 . The second component  22  has the same configuration owing to the one part geometry of the first and second components  20 ,  22  of the polarizer assembly  12 . 
     As the second component  22  is rotated relative to the first component  20  from the pre-assembled position of  FIG. 4  to the assembled position of  FIG. 2 , the edges  52  of the second channel portion  32  are gradually clamped into an interference fit with the edges  50  of the first channel portion  30 . During the rotation of the second component  22  relative to the first component  20 , the first locking projections and/or first openings  100   a ,  100   b  on opposite sides of the first channel portion  30  gradually engage and mate with the respective second locking projections and/or second openings  102   b ,  102   a  on opposite sides of the second channel portion  32 , to thereby gradually compress the edges  52  of the second channel portion  32  into interference fit with the edges  50  of the first channel portion  30  to form a tight seal bead along the edges  50 ,  52  of the respective first and second channel portions  30 ,  32 . In effect, the first locking projections and/or first openings  100   a ,  100   b  and the second locking projections and/or second openings  102   b ,  102   a  gradually urge the second component  22  closer and closer together with the first component  20  in a corkscrew like manner. 
     An interference fit at the edges  50 ,  52  of the first and second channel portions  30 ,  32  can also be implemented at the feed horn connection end  90  of the polarizer assembly  12 . The configuration and description of the flanges of the first and second components  20 ,  22  would be as shown and described for the central portion of the polarizer assembly  12 , which was described above with respect to  FIG. 14B . As such, a cross section of the first component  20  at the feed horn end  90  and description thereof is omitted. 
     The interference fit at the edges  50 ,  52  of the channel portions  30 ,  32  can be created in any number of ways and need not be limited to that which is described with respect to  FIGS. 14A and 14B , as will be appreciated. In one form, for example, for the first component  20 , the first flanges  40   a ,  40   b  may be curved rather than ramped from the edges  50  of the first channel portion  30  to the outer edges  70   a ,  70   b  of the first flanges  40   a ,  40   b  in  FIGS. 14A and 14B , with the clamping centerlines  116 ,  118  forming the bottom of the curve in  FIG. 14B . In another form, the first flanges  40   a ,  40   b  may have a slightly greater thickness at the edges  50  of the first channel portion  30  than at the outer edges  70   a ,  70   b  of the first flanges  40   a ,  40   b  to create an interference fit with the corresponding edges  52  of the opposing second component  22 . The first flanges  40   a ,  40   b  for example can be tapered from the edges  50  of the first channel portion  30  to the outer edges  70   a ,  70   b  of the first flanges  40   a ,  40   b.    
     It will be appreciated that, in certain applications, an interference fit such as described with respect to  FIGS. 14A and 14B  may not be necessary or desired. In such case, the ramps at  500  and  506  may be omitted. It will also be appreciated that, as described above, the mating together of the first and second components  20 ,  22  by the first locking projections and/or first openings  100   a ,  100   b  with the opposite respective second locking projections and/or second openings  102   b ,  102   a  can be by way of an interference fit that yields an engaging and compressing together of the first and second components  20 ,  22  to form a tight seal bead at the edges  50 ,  52  of the respective channel portions  30 ,  32 , even without the interference fit configurations described with respect to  FIGS. 14A and 14B . 
     It will further be appreciated that, in certain applications, an interference fit such as described with respect to  FIGS. 14A and 14B  may be the main source of interference fitting the edges  50 ,  52  of the respective channel portions  30 ,  32 . Thus, for example, the mating together of the first and second components  20 ,  22  by the first locking projections and/or first openings  100   a ,  100   b  with the opposite respective second locking projections and/or second openings  102   b ,  102   a  can be by way of a sliding and/or seating fit, and in this sliding and/or seating fit the first locking projections and/or first openings  100   a ,  100   b  gradually engage and mate with the respective second locking projections and/or second openings  102   b ,  102   a , to thereby gradually compress the edges  52  of the second channel portion  32  into interference fit with the edges  50  of the first channel portion  30  to form a tight seal bead along the edges  50 ,  52  of the respective first and second channel portions  30 ,  32 . The compressing together of the edges  50 ,  52  can be by way of the axial locking functions described above with respect to the locking mechanisms  200 , the snap locking mechanisms  400 , and the engaging of the locking tabs  120   a ,  130   a ,  122   a ,  132   a  with the respective mating slots  122   b ,  132   b ,  120   b ,  130   b , whether or not the axial locking functions themselves are configured for interference fits. 
     As shown in  FIGS. 2-3 , the common rotation axis C-C, or pivot location, of the first and second components  20 ,  22  is located at the waveguide connection end  88  of the polarizer assembly  12 , approximately midway along the “diamond” shape portion of the channel  34 . It will be appreciated that the common rotation axis C-C could be located elsewhere along the length of the first and second components  20 ,  22 . For example, the common rotation axis C-C may be located at the feed horn connection end  90  of the polarizer assembly  12 , or in the central portion between the waveguide connection end  88  and the feed horn connection end  90  of the polarizer assembly  12 . It will be appreciated that a 0.5 (half) degree of angular misalignment about the axis C-C translates into a greater arc distance misalignment at the far end than at the pivot end C-C. The inventor has found that in certain applications the feed horn connection end  90  of the polarizer assembly  12  is more forgiving than the waveguide connection end  88  in terms of how angular misalignment affects performance of the polarizer assembly  12 . It therefore is preferable that the effects of angular misalignment be minimized at the waveguide connection end  88 . By placing the common rotation axis C-C at the waveguide connection end  88 , angular misalignment translates into significantly less arc distance misalignment at the waveguide connection end  88  than if the common rotation axis C-C was located at the feed horn connection end  90 . Of course, in other applications it may be preferable to locate the common rotation axis C-C closer to the feed horn connection end  90  than the waveguide connection end  88 . 
       FIG. 15  shows a flowchart  600  of an exemplary method of assembling a polarizer assembly  12 . In the first step  602 , the first component  20  is axially aligned with the second component  22  along the common rotation axis C-C, as shown in  FIG. 4 . The first component  20  includes the first channel portion  30  extending along the first component axis A-A and having the plurality of first locking projections and/or first openings  100   a ,  100   b  on opposite sides of the first channel portion  30 . The second component  22  includes the second channel portion  32  extending along the second component axis B-B and having the plurality of second locking projections and/or second openings  102   a ,  102   b  on opposite sides of the second channel portion  32 . In the second step  604 , the first component axis A-A of the first component  20  is arranged to be angularly offset about the common rotation axis C-C relative to the second component axis B-B of the second component  22 , as shown in  FIG. 4 . In the third step  606 , the second component  22  is rotated relative to the first component  20  about the common rotation axis C-C from the pre-assembled position shown in  FIG. 4  to the assembled position shown in  FIG. 2 , whereby the first locking projections and/or first openings  100   a ,  100   b  mate with the second locking projections and/or second openings  102   a ,  102   b  and the first and second channel portions  30 ,  32  form the channel  34  that functions to polarize waveforms. 
     Referring to the embodiment illustrated in  FIGS. 4 and 5 , the step  602  of axially aligning the first and second components  20 ,  22  along the common rotation axis C-C can include sliding the post  210  of the first component  20  axially into the opening  212  in the second component  22  in the direction of the common rotation axis C-C. 
     As was also described above with respect to the mating of the plurality of first locking projections and/or first openings  100   a ,  100   b  and the plurality of second locking projections and/or second openings  102   a ,  102   b , as well as with respect to the sloping of the flanges in the embodiment of  FIGS. 14A and 14B , as the second component  22  is rotated relative to the first component  20  from the pre-assembled position to the assembled position, the edges  52  of the second channel portion  32  can be gradually clamped into an interference fit with the edges  50  of the first channel portion  30 . 
     As was described with respect to the embodiment of  FIG. 7  and  FIGS. 10-13 , the method may also include flexing the spring actuated tab  140   a  away from the second component  22  as the second component  22  is rotated from the pre-assembled position toward the assembled position, and flexing the spring actuated tab  140   a  back toward the second component  22  in the assembled position to rotationally lock the second component  22  to the first component  20 . 
     Although the invention has been shown and described with respect to a certain embodiment or embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described elements (components, assemblies, devices, compositions, etc.), the terms (including a reference to a “means”) used to describe such elements are intended to correspond, unless otherwise indicated, to any element which performs the specified function of the described element (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment or embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one or more of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.