Patent Publication Number: US-7900490-B2

Title: Method for engaging with a projection of a first component to removably secure a second component to the first component

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a divisional of U.S. application Ser. No. 10/970,071 filed Oct. 20, 2004, entitled Port Cover for a System Integrated Into a Structure for Injection of a Material Into One or More Cavities in the Structure, which claims priority under 35 U.S.C. §119(e) of provisional application Ser. No. 60/572,288 filed May 18, 2004. 
    
    
     TECHNICAL FIELD 
     This invention relates generally to systems integrated into structures for injection of materials into cavities of the structures, and more particularly to a method for engaging with a projection of a first component to removably secure a second component to the first component. 
     BACKGROUND 
     A structure such as a home or building may include a system integrated into the structure for injection of a material into one or more cavities in the structure. For example, the material may include pesticide and the cavities may include stud bays, crawl spaces, or any other suitable cavities according to particular needs. In this example, a number of externally accessible ports may each be coupled to a tube that passes through one or more cavities and includes perforations through which the injected pesticide is released into the one or more cavities to provide pest control. The externally accessible ports may be accessible to any suitable service provider, such as an exterminator, who may connect a device to the externally accessible ports to inject the material, such as pesticide, into the one or more cavities. This may be undesirable if a particular service provider, such as may be associated with the construction of the structure, desires to be the exclusive provider of such services. Merely covering the one or more externally accessible ports inadequately prevents unauthorized access to the ports. 
     SUMMARY OF THE INVENTION 
     According to the present invention, disadvantages and problems associated with previous techniques for preventing unauthorized access to ports of a system integrated into a structure for injection of a material into cavities in the structure may be reduced or eliminated. 
     In certain embodiments, the present invention includes a method for engaging with a projection of a first component to removably secure a second component to the first component. The method includes positioning a rotatable member of the second component in a first rotational orientation such that the rotatable member is allowed to receive, via a gap in a perimeter of the rotatable member, the projection of the first component. The method also includes positioning the rotatable member in a second rotational orientation such that the rotatable member is prevented from disengaging with the projection of the first component to secure the second component to the first component. The method also includes returning the rotatable member to the first rotational orientation such that the rotatable member is allowed to release, via the gap in the perimeter, the projection of the first component to remove the second component from the first component. 
     Particular embodiments of the present invention may provide one or more technical advantages. For example, it may be desirable to substantially prevent unauthorized access to ports for injection of material into cavities in a structure. Additionally, it may be desirable to provide evidence that a port cover for preventing such access to the ports has been forcibly breached. These objectives may be desirable if a particular service provider for injection of the material into the cavities desires to control access to the ports. In certain embodiments, the overall shape and design of the port cover may help prevent the port cover from being forcibly breached. In certain embodiments, when the locking mechanism is engaged with the projection of the base and the one or more tabs of the cover are engaged with the one or more corresponding slots of the base, the cover may not be removed from the base without breaking the one or more tabs of the cover. Breakage of one or more of the tabs may make it difficult or impossible to replace the cover on the base, which may deter attempts to forcibly breach the port cover and may also provide evidence that the port cover has been forcibly breached. 
     Certain embodiments of the present invention may provide some, all, or none of the above technical advantages. Certain embodiments may provide one or more other technical advantages, one or more of which may be readily apparent to those skilled in the art from the figures, descriptions, and claims included herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present invention and features and advantages thereof, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which: 
         FIGS. 1A-1B  illustrate an example port cover for a system integrated into a structure for injection of a material into one or more cavities in the structure; 
         FIG. 2  illustrates an exploded view of a base showing example components of the base; 
         FIGS. 3A-3B  illustrate front and rear views, respectively, of an example cover and front and rear exploded views, respectively, of an example locking mechanism for removably securing the cover to the base to prevent unauthorized access to one or more ports; 
         FIG. 4  illustrates an example method for securing the cover to the base; 
         FIGS. 5A-5E  illustrate an example process for engaging a rotatable member of a locking mechanism with a projection of the base using a key according to one embodiment of the present invention; and 
         FIG. 6  illustrates an example method for removing the cover from the base. 
     
    
    
     DESCRIPTION OF EXAMPLE EMBODIMENTS 
       FIGS. 1A-1B  illustrate an example port cover  10  for a system integrated into a structure for injection of a material into one or more cavities in the structure. For example, the material may include pesticide, the structure may include a building, a home, or any other suitable structure, and the cavities may include stud bays, crawl spaces, or any other suitable cavities according to particular needs. In this example, a number of externally accessible ports may each be coupled to a tube that passes through one or more cavities and includes perforations through which the injected pesticide is released into the one or more cavities to provide pest control. Port cover  10  may have an overall shape that makes it attractive, but hinders or deters forcible breach of port cover  10 . 
     Port cover  10  includes a base  12  for permanently coupling to the structure and a cover  14  for removably coupling to base  12 . For example, base  12  may be permanently coupled to the structure using one or more screws  16  inserted in corresponding openings  18  of base  12 . Although a particular number of screws  16  and corresponding openings  18  are illustrated, the present invention contemplates base  12  including any suitable number of openings  18  for engaging screws  16 . Furthermore, although screws  16  are described, the present invention contemplates using nails are other suitable fasteners for permanently coupling base  12  to the structure. In certain embodiments, base  12  may be coupled to the structure using a bracket  20 . Although bracket  20  is illustrated as having a particular construction and shape, the present invention contemplates bracket  20  comprising any suitable construction and shape. Furthermore, the present invention contemplates mounting base  12  directly to the structure without the use of bracket  20 . Bracket  20  may also be referred to as a “mud flap.” 
     Base  12  may include one or more port holes  22  associated with a tub insert  24  for injection of the material through corresponding tubes into cavities in the structure. For example, a service representative, such as an exterminator, may connect a device to port holes  22  to inject the material, such as pesticide, into the one or more cavities. Although a particular number of port holes  22  are illustrated, the present invention contemplates base  12  including any suitable number of port holes  22  each having any suitable size according to particular needs. Port holes  22  may be associated one or more ports of base  12  underlying tube insert  24 , as described in more detail with reference to  FIG. 2 . Tube insert  24  may help facilitate connection of the device for injection of the material (e.g., pesticide) into the structure via the underlying ports. The underlying ports of base  12  are preferably sized to snugly accommodate corresponding tubes, and may be crimped or otherwise formed to secure the tubes in place. In certain embodiments, port holes  22  and the underlying ports are recessed from a wall  26  of base  12 . 
     Base  12  includes a projection  28 . In certain embodiments, projection  28  is associated with one of the openings  18  (e.g., opening  18   a ) for engaging a screw  16 . In such embodiments, it may be desirable for projection  28  to be hollow so that a screw  16  may be inserted through projection  28  into opening  18   a . In certain embodiments, projection  28  is formed of the same material as and is integral to base  12 . In embodiments in which projection  28  is associated with an opening for insertion of a screw  16 , opening  18   a  extends through projection  28 . In certain other embodiments, projection  28  is not associated with opening  18   a  for insertion of a screw  16 , and projection may be solid. In yet other embodiments, projection  28  is an insert for inserting into opening  18   a . For example, projection  28  of base  12  may be an insert made of metal or another suitable material, which can be slid into opening  18   a  of base  12 . In certain embodiments in which projection  28  of base  12  is an insert, it may be desirable for the insert to be hollow so as not to impede access to opening  18   a , for insertion of a screw  16  for example. 
     Base  12  may include one or more slots  30 . Although a particular number of slots  30  are illustrated, the present invention contemplates base  12  including any suitable number of slots  30 , according to particular needs. Base  12  may also include one or more channels  32  each associated with a corresponding slot  30 . As can be seen in the embodiment of base  12  illustrated in  FIG. 1A , certain slots  30  (e.g., slots  30   e  and  30   f ) may not be associated with a corresponding channel  32 . In such embodiments, slots  30   e  and  30   f  may be associated with a tab  34 . A perimeter  36  of base  12  may be substantially oval-shaped, although the present invention contemplates perimeter  36  of base  12  having any suitable shape, according to particular needs. Base  12  may be constructed using any suitable material, preferably a hard material such as plastic or metal. 
       FIG. 2  illustrates an exploded view of base  12  showing example components of base  12 . In the embodiment illustrated in  FIG. 2 , projection  28  of base  12  is an insert for inserting into opening  18   a  in base  12 . As discussed above, base  12  may be coupled to the structure using one or more screws  16 . In embodiments in which projection  28  is an insert for inserting into opening  18   a  (such as is illustrated in  FIG. 2 ), screw  16  may be used to permanently couple projection  28  to base  12  when base  12  is permanently coupled to the structure using a screw  16  inserted into opening  18   a.    
     Base  12  includes one or more ports  38 , which may each be coupled to a tube that passes through one or more cavities and includes perforations through which the injected material (e.g., pesticide) is released into the one or more cavities to provide a service (e.g., pest control), as described above with reference to  FIG. 1 . Ports  38  of base  12  are preferably sized to snugly accommodate corresponding tubes, and may be crimped or otherwise formed to secure the tubes in place. In certain embodiments, ports  38  are recessed from wall  26  of base  12 . Although a particular number of ports  38  are illustrated, the present invention contemplates base  12  including any suitable number of ports  38 , according to particular needs. 
     In certain embodiments, a retainer plate  40  may be inserted over ports  38  of base  12 , between tube insert  24  and ports  38  for example. Retainer plate  40  may include one or more slits  42  so that the material injected into the structure using port cover  10  (e.g., via tube insert  24 ) may pass through retainer plate  40  and be injected into the structure through ports  38 . Slits  42  may have any suitable size and shape, according to particular needs. 
     Tube insert  24  may be mounted over retainer plate  40  and ports  38 . Tube insert  24  may include one or more tabs  44 , which may be inserted into and are adapted to engage with corresponding slots  46  of base  12 , helping to secure tube insert  24  to base  12 . Tube insert  24  preferably includes a number of port holes  22  equal to the number of ports  38 , although this is not required. Although tube insert  24  and retainer plate  40  are described, the present invention contemplates port cover  10  with or without either tube insert  24  or retainer plate  40 . For example, in embodiments in which neither tube insert  24  nor retainer plate  40  are included in port cover  10 , a device for injection of the material into one or more cavities of the structure may be directly attached to ports  38  of base  12 . As another example, in embodiments in which retainer plate  40  is not included in port cover  10 , tube insert  24  may be mounted directly over ports  38 . 
     Returning to FIGS. lA and  1 B, cover  14  may include one or more tabs  48  adapted to engage with one or more corresponding slots  30  of base  12 . Although a particular number of tabs  48  are illustrated, the present invention contemplates cover  14  including any suitable number of tabs  48  according to particular needs. In one embodiment, the number of tabs  48  of cover  14  is equivalent to the number of slots  30  of base  12 . In certain embodiments, one or more of slots  30  (e.g., slots  30   e  and  30   f ) are each associated with a tab  34  of base  12 , which may help prevent the cover from being forcibly pulled perpendicular to a surface  50  of base  12  when cover  14  is secured to base  12  to help prevent port cover  10  from being forcibly breached. A perimeter  52  of cover  14  may be substantially oval-shaped, although the present invention contemplates perimeter  52  of cover  14  having any suitable shape, according to particular needs. In certain embodiments, perimeter  36  of base  12  and perimeter  52  of cover  14  have matching substantially oval-shapes, and perimeters  36  and  52  substantially align when cover  14  is secured to base  12  to help prevent port cover  10  from being forcibly breached. Although the present invention contemplates cover  14  having any suitable shape, it may be preferable for cover  14  to be dome-shaped or otherwise lack sharp edges to further hinder or deter forcible breach of port cover  10 . Cover  14  may be constructed using any suitable material, preferably a hard material such as plastic or metal. 
     In certain embodiments, cover  14  may include an interior frame  54  that includes tabs  48 , a void  56  existing between an exterior wall  58  and interior frame  54  of cover  14 . Cover  14  may include one or more buttresses  60  in void  56 , each buttress  60  connecting a corresponding portion of interior frame  54  to a corresponding portion of exterior wall  58 , buttresses  60  helping to prevent port cover  10  from being forcibly breached when cover  14  is secured to base  12 . 
     Port cover  10  includes a locking mechanism  62  in an aperture  63  of cover  14  for removably securing cover  14  to base  12  to prevent unauthorized access to ports  38 . As described in more detail below with reference to  FIGS. 5A-5E , locking mechanism  62  is adapted to engage projection  28  of base  12  to removably secure tabs  48  of cover  14  in engagement with corresponding slots  30  of base  12  to removably secure cover  14  to base  12  to prevent unauthorized access to ports  38 . In certain embodiments, when locking mechanism  62  is engaged with projection  28  of base  12  and tabs  48  of cover  14  are engaged with corresponding slots  30  of base  12 , cover  14  cannot be removed from base  12  without breaking one or more of tabs  48  of cover  14 . In certain embodiments, when tabs  48  of cover  14  are engaged with corresponding slots  30  of base  12 , locking mechanism  62  being engaged with projection  28  of base  12  substantially prevents cover  14  from sliding downward substantially parallel to front surface  50  of base  12 , and tabs  48  of cover  14  being engaged with corresponding slots  30  of base  12  substantially prevents cover  14  from being pulled substantially perpendicular to front surface  50  of base  12  or from sliding upward substantially parallel to front surface  50  of base  12 . 
     In certain embodiments, locking mechanism  62  includes a rotatable member  64  having a perimeter  66  and a gap  68  in perimeter  66 . Although rotatable member  64  is illustrated as being substantially horseshoe-shaped, the present invention contemplates rotatable member  64  having any suitable shape, according to particular needs, such that rotatable member  64  has a perimeter  66  and a gap  68  in perimeter  66 . Rotatable member  64  is adapted to be rotated to engage with and disengage from projection  28  of base  12 . For example, as described in more detail below with reference to  FIGS. 5A-5E , locking mechanism  62  may be adapted to engage with a key  70  inserted in locking mechanism  62  and to be rotated using key  70 . Key  70  includes a shaft  72  and a handle  74 . In certain embodiments, cover  14  includes a tab  76  in aperture  63 , tab  76  being adapted to engage a channel  78  of key  70  when channel  78  is aligned with tab  76  and key  70  is inserted into aperture  63  to engage locking mechanism  62 . 
     In certain embodiments, when rotatable member  64  is in a first rotational orientation, rotatable member  64  is adapted to receive, via gap  68  in perimeter  66 , projection  28  of base  12  and to allow tabs  48  of cover  14  to slide upward substantially parallel to front surface  50  of base  12  to engage with corresponding slots  30  of base  12  to secure cover  14  to base  12 . In alternative embodiments, slots  30  of base  12  may be oriented such that tabs  48  of cover  14  slide downward substantially parallel to front surface  50  of base  12  to engage with corresponding slots  30  of base  12 . Tabs  48  may be adapted to move inward substantially perpendicular to front surface  50  of base  12  through corresponding channels  32  of base  12  before sliding upward (or downward) to engage corresponding slots  30  of base  12 . 
     When rotatable member  64  is in a second rotational orientation, rotatable member  64  is prevented from disengaging with projection  28  of base  12 , to substantially prevent tabs  48  of cover  14  from sliding downward substantially parallel to front surface  50  of base  12  to disengage from corresponding slots  30  of base  12  to secure cover  14  to base  12 . 
     When rotatable member  64  is returned to the first rotational orientation, rotatable member  64  is adapted to release, via gap  68  in perimeter  66 , projection  28  of base  12  and to allow tabs  48  of cover  14  to slide downward substantially parallel to front surface  50  of base  12  to disengage from corresponding slots  30  of base  12  to remove cover  14  from base  12 . In alternative embodiments, slots  30  of base  12  may be oriented such that tabs  48  of cover  14  slide upward substantially parallel to front surface  50  of base  12  to disengage from corresponding slots  30  of base  12 . Tabs  48  may be adapted to, after sliding downward (or upward) to disengage from corresponding slots  30  of base  12 , move outward substantially perpendicular to front surface  50  of base  12  through corresponding channels  32  of base  12 . 
     In certain embodiments, the first rotational orientation comprises at least one of a first range of rotational orientations, and the second rotational orientation comprises at least one of a second range of rotational orientations. For example, the first range of rotational orientations may include the rotational orientations at which rotatable member  64  is allowed to engage with by receiving and releasing projection  28  via gap  68  in perimeter  66  and the second range of rotational orientations may include the rotational orientations at which rotatable member  64  is prevented from disengaging with projection  28  via gap  68  in perimeter  66 . 
       FIGS. 3A-3B  illustrate front and rear views, respectively, of an example cover  14  and front and rear exploded views, respectively, of an example locking mechanism  62  for removably securing cover  14  to base  12  to prevent unauthorized access to ports  38 . Cover  14  includes a castellated member  80 , which includes a plurality of castellations  82 . In certain embodiments, castellated member  80  is substantially circular in shape, castellations  82  being in a substantially circular arrangement. Although a particular number of castellations  82  are illustrated, the present invention contemplates castellated member  80  including any suitable number of castellations  82 , according to particular needs. A slot  84  separates each pair of adjacent castellations  82 . Slots  84  may have any suitable width, according to particular needs. 
     Locking mechanism  62  includes a tumbler  86  adapted to engage castellated member  80 . Tumbler  86  includes a plurality of legs  88  arranged in a substantially circular fashion. In certain embodiments, legs  88  are angled away from a center of the circle at joints  90  of legs  88 . One or more of the legs  88  each include a projection  92  adapted to extend into a corresponding slot  84  of castellated member  80  that separates adjacent castellations  82 . In certain embodiments, one or more of legs  88  lack a projection  92  (e.g., leg  88   a ) for reasons described in more detail below with reference to  FIGS. 5A-5E . In certain embodiments, the width of slots  84  is only slightly greater than a width of the corresponding legs  88  of tumbler  86 . 
     Locking mechanism  62  includes a lock plug  94  adapted to receive tumbler  86 . For example, lock plug  94  may include a plurality of channels  96  each adapted to receive a corresponding leg  88  of tumbler  86 , joints  90  of legs  88  being exposed in lock plug  94  at end portions  98  of channels  96 . In certain embodiments, the width of channels  96  of lock plug  94  is only slightly greater than the width of corresponding legs  88  of tumbler  86 . A perimeter  100  of lock plug  94  may have a substantially tubular shape. Lock plug  94  is further adapted to engage projections  102  of key  74  at end portions  98  of channels  96 , as described in greater detail below with reference to  FIGS. 5A-5E . Lock plug  94  may include a substantially tubular member  104  extending into aperture  63  of cover  14  adapted to receive key  74 . Projections  92  of legs  88  of tumbler  86  extend beyond perimeter  100  of lock plug  94 , such that projections  92  extend into corresponding slots  84  of castellated member  80  to prevent rotation of lock plug  94 . 
     Locking mechanism  62  includes rotatable member  64 , which is adapted to engage projection  28  of base  12  as described briefly above with reference to  FIGS. 1A and 1B , and in more detail below with reference to  FIGS. 5A-5E . Rotatable member  64  may include a base ring  106 , which may include one or more knobs  108  each adapted to engage with a corresponding aperture  110  in lock plug  94 . Knobs  108  engaging with corresponding apertures  110  of lock plug  94  may help secure projections  92  of legs  88  in corresponding channels  96  of lock plug  94 . 
     In certain embodiments, locking mechanism  62  includes a housing  112  adapted to seat over rotatable member  64  to maintain rotatable member  64  in continuous contact with lock plug  94 , legs  88  of tumbler  86  in continuous contact with lock plug  94  and rotatable member  64 , and lock plug  94  in continuous contact with cover  14 . For example, housing  112  may help hold the components of locking mechanism  62  together. In certain embodiments, housing  112  includes one or more apertures  114 , which may permanently or removably engage with one or more corresponding projections  116  of cover  14 . 
     Channels of lock plug  94  and legs  88  of tumbler  86  are adapted to engage with key  70  inserted into locking mechanism  62 . For example, channels  96  of lock plug  94  are adapted to receive projections  102  of key  70 , one or more of the projections  102  of key  70  being adapted to, when the key is appropriately oriented, disengage projections  92  of the one or more legs  88  of tumbler  86  from the corresponding slots  84  of adjacent castellations  82  to allow lock plug  94  to be rotated using key  70 . In certain embodiments, projections  102  of key  70  are adapted to compress legs  88  of tumbler  86  inward to recess projections  92  of tumbler  86  from slots  84  of castellated member  80  such that projections  92  clear castellations  82 . Projections  92  of tumbler  86  being recessed from slots  84  of castellated member  80  allows lock plug  94  to be rotated using key  70 , rotating rotatable member  64 . 
       FIG. 4  illustrates an example method for securing cover  14  to base  12 .  FIG. 4  will be described in conjunction with  FIGS. 5A-5E , which illustrate an example process for engaging rotatable member  64  of locking mechanism  62  with projection  28  of base  12  using key  70  according to one embodiment of the present invention. In particular,  FIG. 5A  illustrates key  70  and locking mechanism  62  with rotatable member  64  in a first rotational orientation such that it is adapted to receive projection  28  of base  12 ;  FIG. 5B  illustrates rotatable member  64  engaged with projection  28  in the first rotational orientation with key  70  oriented to engage with lock plug  94  and legs  88  of tumbler  86 ;  FIG. 5C  illustrates key  70  engaged with locking mechanism  62  with projections  92  of legs  88  recessed from slots  84 ;  FIG. 5D  illustrates the rotation of rotatable member  64  to a second rotational orientation using key  70  to secure rotatable member  64  in engagement with projection  28  of base  12  in the second rotational orientation; and  FIG. 5E  illustrates rotatable member  64  engaged with projection  28  of base  12  in the second rotational orientation and key  70  withdrawn from locking mechanism  62 . It will be assumed for purposes of describing the example method of  FIG. 4  that rotatable member  64  begins at the first rotational orientation such that rotatable member  64  is oriented to receive projection  28  of base  12  via gap  68  in perimeter  66  of rotatable member  64 . 
     As shown in  FIG. 4 , at step  200 , cover  14  is positioned such that tabs  48  of cover  14  are moved inward substantially perpendicular to front surface  50  of base  12  through corresponding channels  32  of base  12 . At step  202 , cover  14  is advanced upward such that tabs  48  slide upward substantially parallel to front surface  50  of base  12  and engage with corresponding slots  30  of base  12 , and locking mechanism  62  engages projection  28  of base  12 . For example, as illustrated in  FIG. 5A , rotatable member  64  of locking mechanism  62  may be in a first rotational orientation such that rotatable member  64  is adapted to receive, via gap  68  in perimeter  66 , projection  28  of base  12 . In alternative embodiments, slots  30  of base  12  may be oriented such that tabs  48  of cover  14  slide downward substantially parallel to front surface  50  of base  12  to engage with corresponding slots  30  of base  12 . In certain embodiments, projection  28  of base  12  includes a channel  116  and rotatable member  64  includes a ridge  118  adapted to engage with channel  116  of projection  28  when rotatable member  64  receives projection  28 . Channel  116  of projection  28  and ridge  118  of rotatable member  64  may help prevent cover  14  from being pulled outward substantially perpendicular to front surface  50  of base  12  when cover  14  is secured to base  12 . 
     At step  204 , key  70  may be oriented for insertion into aperture  63  of cover  14  and into locking mechanism  62 . For example, as shown in  FIG. 5B , projections  102  of key  70  may be oriented to align with channels  96  of lock plug  94  and legs  88  of tumbler  86 . In embodiments in which aperture  63  of base  12  includes tab  76 , channel  78  of key  70  may be oriented such that channel  78  is aligned with tab  76  and can receive tab  76  as key  70  is inserted into aperture  63 . In such embodiments, protrusions  102  of key  70  may be properly aligned with channels  96  of lock plug  94  and legs  88  of tumbler  86  when channel  78  of key  70  is aligned with tab  76  of aperture  63  if key  70  is properly “coded” to engage with locking mechanism  62 . 
     For example, as shown in  FIG. 5C , one or more of legs  88  of tumbler may include a joint  90  that is recessed from the other joints  90  of legs  88  of tumbler  86 , and which does not include a corresponding projection  92 . This may allow key  70  to be coded. For example, suppose tumbler  86  includes six legs  88 , one of which includes a joint  90  that is recessed from the other joints  90  and does not include a projection  92 . In order to rotate lock plug  94  associated with tumbler  86 , the five projections  92  of the other five legs  88  should be recessed from corresponding slots  84  of castellated member  80 ; thus, the other five legs  88  should be compressed inward using key  70 . However, if key  70  includes six projections  102 , it may not be possible to insert key  70  into channels  96  of lock plug  94  due to the recessed joint  90 , which may block a projection  102  of key  70  inserted into its corresponding channel  96 . Furthermore, if key  70  does not have sufficient projections  102  or if projections  102  are in incorrect locations, key  70  will not be able to recess all projections  92  of legs  88 , preventing rotatable member  64  from being rotated without breaking one or more projections  92  of legs  88 . 
     At step  206 , key  70  is inserted into aperture  63  of cover  14  and locking mechanism  62  according to the orientation described at step  204 , and sufficient pressure is applied to compress legs  88  of tumbler  86  inward and recess projections  92  of legs  88  from corresponding slots  84  of castellated member  80 . Recessing projections  92  of legs  88  from corresponding slots  84  of castellated member  80  may allow lock plug  94  to be rotated using key  70 , thereby rotating rotatable member  64 . For example, as shown in  FIG. 5C , projections  102  of key  70  are engaged with corresponding legs  88  of tumbler  86  in channels  96  of lock plug  94 , and projections  92  of legs  88  are recessed from corresponding slots  84  of castellated member  80  such that projections  92  clear castellations  82 . This recession allows rotatable member  64  to be rotated using key  70  by rotating lock plug  94 . In certain embodiments, end portions  120  of projections  102  of key  70 , which engage with legs  88  of tumbler  86 , are angled to facilitate inward compression of legs  88  for retracting projections  92  of legs  88  from corresponding slots  84  of castellated member  80 . 
     At step  208 , key  70 , inserted in locking mechanism  62  and recessing projections  92  of legs  88  from corresponding slots  84  of castellated member  80 , may be turned to rotate rotatable member  64  of locking mechanism  62  to the second rotational orientation for engaging with projection  28  of base  12 . In certain embodiments, as illustrated in  FIG. 5D , rotatable member  64  should be rotated approximately one hundred eighty degrees to engage with projection  28  of base  12 . In embodiments in which shaft  72  of key  70  includes channel  78  for allowing tab  76  of aperture  63  of base  12  to pass through when inserting key  70  into locking mechanism  62 , channel  78  of shaft  72  may extend around the perimeter of shaft  72  such that tab  76  of aperture  63  prevents key  70  from being turned beyond certain points in certain directions. For example, channel  78  of key  70  may prevent key  70  from being turned beyond approximately one hundred eighty degrees in a clockwise direction when turning key  70  to engage rotatable member  64  with projection  28 . 
     At step  210 , as shown in  FIG. 5E , key  70  is removed from locking mechanism  62 , releasing inward pressure on legs  88 , allowing projections  92  of legs  88  to engage with corresponding slots  84  of castellated member  80 , and removably securing tabs  48  of cover  14  with corresponding slots  30  of base  12  to removably secure cover  14  to base  12  to prevent unauthorized access to ports  38 . In certain embodiments, when rotatable member  64  is in the second rotational orientation, rotatable member  64  is prevented from disengaging with projection  28  of base  12 , to substantially prevent tabs  48  of cover  14  from sliding downward substantially parallel to front surface  50  of base  12  to disengage from corresponding slots  30  of base  12  to secure cover  14  to base  12 . 
       FIG. 6  illustrates an example method for removing cover  14  from base  12 . At step  300 , key  70  may be oriented for insertion into aperture  64  of cover  14 . For example, as shown in  FIG. 5B , projections  102  of key  70  may be oriented to align with channels  96  of lock plug  94  and legs  88  of tumbler  86 . In embodiments in which aperture  63  of base  12  includes tab  76 , channel  78  of key  70  may be oriented such that channel  78  is aligned with tab  76 . In such embodiments, projections  102  of key  70  may be properly aligned with channels  96  of lock plug  94  and legs  88  of tumbler  86  when channel  78  of key  70  is aligned with tab  76  of aperture  63  if key  70  is properly coded for locking mechanism  62  and port cover  14 . 
     At step  302 , key  70  is inserted into aperture  63  of cover  14  according to the orientation described at step  200 , and sufficient pressure is applied to compress legs  88  of tumbler  86  inward and to recess projections  92  of legs  88  from corresponding slots  84  of castellated member  80 . Recessing projections  92  of legs  88  from corresponding slots  84  of castellated member  80  may allow lock plug  94  to be rotated using key  70 , thereby rotating rotatable member  64 . For example, as shown in  FIG. 5C , projections  102  of key  70  are engaged with corresponding legs  88  of tumbler  86  in channels  96  of lock plug  94 , and projections  92  of legs  88  are recessed from corresponding slots  84  of castellated member  80  such that projections  92  clear castellations  82 . This recession allows rotatable member  64  to be rotated using key  70  by rotating lock plug  94 . As discussed above with reference to  FIG. 4 , key  70  may be coded such that only a properly coded key  70  may be used to compress legs  88  to recess projections  92  of legs  88  from corresponding slots  84  of castellated member  80 . 
     At step  304 , key  70 , inserted in locking mechanism  62  and recessing projections  92  of legs  88  from corresponding slots  84  of castellated member  80 , may be turned to rotate rotatable member  64  of locking mechanism  62  to the first rotational orientation for disengaging from projection  28  of base  12 . In certain embodiments, rotatable member  64  should be rotated approximately one hundred eighty degrees to disengage with projection  28  of base  12 . In embodiments in which shaft  72  of key  70  includes channel  78  for allowing tab  76  of aperture  63  of base  12  to pass through when inserting key  70  into locking mechanism  62 , channel  78  of shaft  72  may extend around shaft  72  such that tab  76  prevents key  70  from being turned beyond certain points in certain directions. For example, channel  78  of key  70  may prevent key  70  from being turned beyond approximately one hundred eighty degrees in a counterclockwise direction when turning key  70  to disengage rotatable member  64  with projection  28 , which may result in tab  76  being aligned with channel  78  of key  70 . 
     At step  306 , key  70  is removed from locking mechanism  62 , releasing inward pressure on legs  88 , allowing projections  92  of legs  88  to engage with corresponding slots  84  of castellated member  80 , and locking rotatable member  64  in the first rotational orientation. At step  308 , with rotatable member  64  in the second rotational orientation, tabs  48  of cover  14  slide downward substantially parallel to front surface  50  of base  12  to disengage from corresponding slots  30  of base  12 . For example, cover  14  may be pulled by an authorized service technician downward substantially parallel to front surface  50  of base  12  to disengage tabs  48  of cover  14  from corresponding slots  30  of base  12 . As another example, the force of gravity may be sufficient to pull cover  14  downward substantially parallel to front surface  50  of base  12  to disengage tabs  48  of cover  14  from corresponding slots  30  of base  12 . In an alternative embodiment, slots  30  of base  12  may be oriented such that tabs  48  of cover  14  slide upward substantially parallel to front surface  50  of base  12  to disengage from corresponding slots  30  of base  12 . At step  310 , tabs  48  of cover  14  are moved outward substantially perpendicular to front surface  50  of base  12  through corresponding channels  32  of base  12 . At step  312 , cover  14  is removed from base  12  to allow access to ports  38 . In practice, step  306  may be performed after removing cover  14  from base  12 . 
     Particular embodiments of the present invention may provide one or more technical advantages. For example, it may be desirable to substantially prevent unauthorized access to ports  38  for injection of material into cavities in a structure. Additionally, it may be desirable to provide evidence that port cover  10  for preventing such access to ports  38  has been forcibly breached. These objectives may be desirable if a particular service provider for injection of the material into the cavities desires to control access to ports  38 . In certain embodiments, the overall shape and design of port cover  10  may help prevent port cover  10  from being forcibly breached. In certain embodiments, when locking mechanism  62  is engaged with projection  28  of base  12  and tabs  48  of cover  14  are engaged with corresponding slots  30  of base  12 , cover  14  may not be removed from base  12  without breaking one or more of tabs  48  of cover  14 . Breakage of one or more of tabs  48  may make it difficult or impossible to replace cover  14  on base  12 , which may deter attempts to forcibly breach port cover  10  and may also provide evidence that port cover  10  has been forcibly breached. 
     Although locking mechanism  62  has been described in the context of a port cover (e.g., port cover  10 ) for use in a system integrated into a structure for injection of a material into one or more cavities in the structure, the present invention contemplates using locking mechanism  62  for engaging with a projection of any suitable first component to removably secure any suitable second component to the first component for any suitable purpose. As just one example, locking mechanism  62  may be used to removably secure a door to a doorframe. 
     Although the present invention has been described with several embodiments, diverse changes, substitutions, variations, alterations, and modifications may be suggested to one skilled in the art, and it is intended that the invention encompass all such changes, substitutions, variations, alterations, and modifications as fall within the spirit and scope of the appended claims.