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You are an expert at summarizing long articles. Proceed to summarize the following text: 
FIELD OF THE INVENTION 
     The present invention relates to a security cover for a door viewer device such as a peephole. 
     BACKGROUND OF THE INVENTION 
     Door viewer devices are security devices that permit a viewer located on one side of the door (e.g., the inside of the door) to observe callers located on the other side of the door (e.g., the outside of the door). Such door viewer devices typically include a lens system that generates a virtual image of the various objects located in front of the door. In operation, a user positioned behind the door peers through the door viewer device to view the immediate area surrounding the door, thereby enabling the person to confirm the identity of persons or objects before opening the door. Conventional door viewer devices suffer from several disadvantages. First, conventional door viewer devices permit two-way viewing. That is, while door viewer devices permit the viewer on the inside to view the area located in front of the door, they further permit a viewer positioned in front of the door to view the area proximate the rear side of the door. In addition, conventional door viewer devices permit outside viewers (i.e., persons located in front of the door) to view changes in light that occur when the insider viewer approaches the door and looks through the peephole. By noting changes in light within the peephole (e.g., from light to dark), the outside viewer is alerted to the fact that someone is located within the structure (e.g., the home, apartment, business, etc.) and is positioned behind the door, which compromises the security of the persons located within the structure. 
     Thus, it would be desirable to provide a security device that prevents outside viewers from viewing into the secured area (e.g., a house, office, etc.), as well as enables an insider viewer to look through the door viewer device without generating changes in light that might occur during viewing. 
     SUMMARY OF THE INVENTION 
     The present invention is directed toward a security cover for a door viewer device such as a peephole. The security cover includes a housing including a forward aperture, a rearward aperture aligned with the forward aperture, and a shutter mechanism disposed between the apertures. The shutter mechanism is repositionable from a closed position to an opened position via engagement of an actuator. In operation, the security cover is coupled to a door such that the cover encloses the peephole and the forward aperture is aligned with the viewing port of the peephole. The cover may further include an eyecup secured to the rearward plate. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  illustrates a front perspective view of a security cover for a door viewer in accordance with an aspect of the present invention. 
         FIG. 1B  illustrates a rear perspective view of the security cover shown in  FIG. 1A . 
         FIG. 2  illustrates an exploded view of the security cover shown in  FIG. 1A . 
         FIGS. 3A and 3B  illustrate rear perspective views of the security cover shown in  FIG. 1A , with the eyecup and back panel removed to show the operation of the shutter mechanism. 
         FIG. 4  illustrates an exploded view of a security cover in accordance with another aspect of the present invention. 
         FIGS. 5A and 5B  illustrate rear perspective views of the security cover shown in  FIG. 4 , with the eyecup and back panel removed to show the operation of the shutter mechanism. 
         FIG. 6  illustrates an exploded view of the security cover in accordance with another aspect of the present invention. 
         FIGS. 7A and 7B  illustrate rear perspective views of the security cover shown in  FIG. 6 , with the eyecup and back panel removed to show the operation of the shutter mechanism. 
         FIG. 8  illustrates an exploded view of a security cover in accordance with another aspect of the invention. 
         FIGS. 9A and 9B  illustrate rear perspective views of a security cover in accordance with an aspect of the invention, with the eyecup and back panel removed to show the shutter mechanism in its closed and open positions, respectively. 
         FIGS. 10A ,  10 B, and  10 C illustrate rear plan views of the device of  FIG. 9A , showing the operation of the shutter mechanism. 
         FIG. 11  illustrates a security cover for a door viewer in accordance with an aspect of the invention. 
     
    
    
     Like reference numerals have been used to identify like elements throughout this disclosure. 
     DETAILED DESCRIPTION OF THE INVENTION 
       FIGS. 1A and 1B  illustrate a security cover for a door view in accordance with an embodiment of the invention. As shown, the security cover  10  includes a housing  100  having a generally cylindrical side wall  105 , an annular forward plate  110  defining a forward aperture  115  and an annular rearward plate  120  defining a rearward or viewing aperture  125 . An eyecup or eye shield  130  (e.g., similar to those found on binoculars) is coupled to the rearward plate  120 , surrounding the viewing aperture. As shown, the forward plate  110  is inset within the body  100 , defining a forward, generally annular rim  135  operable to contact the door surface. The rim  135  may be treated such that it couples to the door surface. By way of example, the rim  135  may be coated with an adhesive. In other embodiments, the security cover  10  may include one or more fastening members (e.g., grommets) extending radially from the housing body  100  to permit fasteners such nails or screws to be utilized to secure the cover  10  to the door. In operation, the security cover  10  is connected to the rear surface of a door such that the rim  135  surrounds the viewing port of the door viewer, and such that the forward aperture generally aligns with the viewing port. Once connected to the door, the inside viewer (i.e., the person located on the back side (or inside) of the door) places an eye against the eyecup  130 , looks through the rearward  125  and forward  115  apertures and through the door viewer. 
     The security cover  10  further includes a shutter mechanism disposed between the apertures  115 ,  125  operable to selectively open and close the viewing aperture  125 . Referring to  FIG. 2 , the rear side  205  of the forward plate  110  includes a first post  210 A laterally spaced from a second post  210 B. Each post  210 A,  210 B extends axially from the rear side or the forward plate  110 . A first shutter member  220 A is pivotally mounted on the first post  210 A and a second shutter member  220 B pivotally mounted on the second post  210 B. The shutter members  220 A,  220 B may be biased towards the center of the aperture (i.e., towards each other) via a biasing member  225  (e.g., a spring) that spans the members. 
     The first shutter member  220 A includes a body  230 A possessing a generally semicircular shape, having a straight edge portion  235 A and a rounded edge portion  240 A. The body  230 A further includes a truncated area  245  along its proximal portion that is configured to frictionally mesh with a protruding area on the second shutter  220 A. The second shutter member  220 B includes a body  230 B possessing a generally semicircular shape, defining a generally straight edge portion  235 B and a generally rounded edge portion  240 B. The rounded edge portions  240 A,  240 B of the shutter members  220 A,  220 B may possess a radius of curvature that corresponds to the radius of curvature of the side wall  105  inner surface. With this configuration, the rounded edge portions  240 A,  240 B are contoured to their respective side wall area. 
     The second shutter member  220 B further includes a lever  250  extending radially from the body  230 B. The base  252  of the lever  250  is configured to engage the truncated area  245  of the first shutter body  230 A such that rotation of the second shutter member  220 B causes an opposite rotation in the first shutter member  220 A (explained in greater detail below). The distal portion of the lever  250  of the second shutter member  220 B extends through an elongated slot  255  formed into side wall  105  of the housing  100 . The slot  255  may define the travel length an operator may move the lever  250  during operation. 
     The operation of the security cover  10  is explained with reference to  FIGS. 3A and 3B . The biasing member  225  biases the shutter members  220 A,  220 B in a normal or closed position, in which the straight edge portions  235 A,  235 B of the shutter members  220 A,  220 B contact each other. In this position, the body  230 A,  230 B of each shutter member  220 A,  220 B at least partially blocks the forward aperture  115 . As such, a viewer positioned on the inside of the door cannot see through the cover  10 . Similarly, a viewer positioned on the outside of the door cannot see light variations through the door viewer, and cannot view the area proximate the interior door surface. Should an inside viewer desire to look through the door viewer, the inside viewer engages the lever  250  to rotate the upper circle of the second shutter member  220 B (i.e., the base  252 ) toward the upper circle of (i.e., truncated portion  245 ) the first shutter member  220 A (e.g., in a clockwise direction from the perspective of  FIG. 3B ). Rotation of the second shutter member  220 B causes the base  252  of the lever  250  to frictionally engage the truncated portion  245  of the first shutter member  220 A; consequently, the clockwise rotation of the second shutter member  220 B rotates the first shutter member  220 A in counterclockwise direction. As a result, the shutter members  220 A,  220 B separate, moving from the normal, closed position ( FIG. 3A ) to an opened position ( FIG. 3B ). Since the outer rounded edges  240 A,  240 B of the shutter members  220 A,  220 B are contoured to the inner surface of the side wall  105 , the shutter members abut the side wall. With this configuration, in the opened position, the bodies  230 A,  230 B of the shutter members  220 A,  220 B clear the forward  115  and rearward  125  apertures enabling an inside viewer may see through the cover  10  and the door viewer device. 
     Thus, the present invention provides an inexpensive, easily operated device that can be attached to any conventional door including a door viewer. The cover  10  is biased in its closed position; consequently, an outside viewer (i.e., a viewer positioned along the front of the door) cannot look through the door viewer to see into the secured structure (e.g., house, apartment, etc.). In addition, the outside viewer cannot see any light variation that occurs as an inside viewer approaches the door viewer device. Should an inside viewer desire to look through the door viewer device, the inside viewer user simply places an eye against the eyecup  130 , further shielding the door viewer device from light, and then engages the lever  250  to open the shutter mechanism as described above. The inside viewer may now view the outside viewer to confirm the outside viewer&#39;s identity. During the viewing process, the outside viewer remains unaware of the presence of the inside viewer since no light variation can be detected. 
       FIG. 4  illustrates a security cover  40  for a door viewer device in accordance with another aspect of the invention. As shown, the cover  40  includes a structure similar to that described above, including a housing  400  with a side wall  405 , and axially extending posts  407 A,  407 B disposed on the rear side  410  of a forward plate  415 . This configuration further includes a first shutter member  420 A including a first lever  425 A and a first body  430 A, as well as a second shutter member  420 B including a second lever  425 B and a second body  430 B. That is, instead of the mechanism including a single lever that controls both shutter members, each shutter member  420 A,  420 B now includes a lever  425 A,  425 B extending radially from the body  430 A,  430 B. The shutter bodies  430 A,  430 B, moreover, may no longer be geared together. The housing  400  further includes a first slot  435 A associated with the first lever  425 A and a second slot  435 B associated with the second lever  425 B. 
     In operation, the shutter mechanism beings in its normal, closed position as shown in  FIG. 5A . The inside viewer engages the levers  425 A,  425 B, driving them toward each other (e.g., the operator squeezes the levers together). Each shutter member  420 A,  420 B pivots on its respective post  407 A,  407 B such that the first shutter member  420 A rotates in one direction (e.g., a counterclockwise direction) while the second shutter member  420 B rotates in an opposite direction (e.g., a clockwise direction). The shutter members  420 A,  420 B are rotated until the bodies  430 A,  430 B clear the forward  450  and rearward  460  apertures. Once clear of the forward aperture  450  clear the inside viewer may look though the security cover  10  and the door viewer device to investigate the area proximate the front of the door. Once the levers  405 A,  405 B are released, the biasing member  455  drives the shutter members  420 A,  420 B back to their normal (closed) position, in which each body  430 A,  430 B at least partially blocks the forward aperture  450 . 
       FIG. 6  illustrates a security cover for a door viewer device in accordance with another aspect of the invention. As shown, the security cover  60  includes a housing  600 , including a side wall  605  with a forward plate  610  defining a forward aperture  615 , a rearward plate  620  defining a rearward or viewing aperture  625 , and an axial post  627  extending distally from the rear side  630  of the forward plate  610 . The cover  60  further includes a single shutter member  640  including a generally circular body  645  and a lever  650  extending radially therefrom. The side wall  605  of the housing  600  further includes a slot  660  that enables passage of the shutter member  640  therethrough. As with the other embodiments, the cover  60  further includes an eyecup  670  secured to the rearward plate  620 . 
     Operation of the device is explained with reference to  FIGS. 7A and 7B . As shown, pivoting the lever  650  drives the body  645  of the shutter member  640  out of alignment with the viewing aperture  625 , enabling an inside viewer to look through the door viewer device. Releasing the lever  650  returns the shutter member  640  to its normal closed position, via gravity. 
       FIGS. 8-10  illustrate a security cover for a door viewer device in accordance with another aspect of the invention. As illustrated, the security cover  80  includes a housing  800  including a side wall  805  defining a rim  807 , a forward annular plate  810  defining a forward aperture  815 , and a rearward annular plate  820  defining a rearward or viewing aperture  825 . As shown, the rim  807  is further coated with an adhesive  840 , which, in turn, is covered with release paper  845 . 
     Referring to  FIGS. 9A and 9B , the shutter mechanism includes a plurality of blades  905 A- 905 F pivotally coupled to the rear side of the forward plate  810  via a post extending from the forward plate rear side in a manner similar to that described above (posts not shown). Each blade  905 A- 905 F possesses a generally tear-drop shape including a proximal narrower end and a distal wider end. Each blade includes a follower pin  910 A- 910 F disposed at an intermediate location along the blade, proximate blade outer edge. In addition, the rearward plate  820  further includes a plurality of radial slots  815 A- 815 F angularly spaced about the plate. Each follower pin  910 A- 910 F is captured within its respective slot  815 A- 815 F, with the slot defining the travel path of each blade. 
     Referring to  FIGS. 10A-10C , with this configuration, rotation of the rearward plate  820  (indicated by arrow R) causes each follower pin  910 A- 910 F to moves along its respective slot  815 A- 815 F, pivoting each blade  905 A- 905 F radially, rotating it from an opened position, in which each blade clears the forward aperture  815  ( FIG. 10A ), to a closed position ( FIG. 10C ), in which each blade at least partially blocks the forward aperture ( FIG. 10C ). That is, the wider end of the blade, defining the distal blade end, at least partially covers the forward aperture  815  in the closed position. To close the shutter mechanism, the rearward plate  820  is rotated in the reverse direction. 
       FIG. 11  illustrates a security cover for a door viewer device in accordance with an aspect of the invention. As shown, the security cover  1100  includes a structure similar to that described above in  FIGS. 1A and 1B . In this configuration, however, the biasing member  1105  is a coil spring coupled to the distal end of the second shutter member  1110 B. As with the embodiment described above regarding  FIG. 1A , movement of the second shutter member  1110 B generates a corresponding movement in the first shutter member  1110 A. 
     While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. For example, the shutter mechanism may include a gear system in which the first shutter member includes teeth that mesh with corresponding teeth on the second shutter member. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. It is to be understood that terms such as “top”, “bottom”, “front”, “rear”, “side”, “height”, “length”, “width”, “upper”, “lower”, “interior”, “exterior”, and the like as may be used herein, merely describe points of reference and do not limit the present invention to any particular orientation or configuration.

Summary:
The present invention is directed toward a security cover for a door viewer such as a peephole. The security cover includes a housing having a forward opening configured to align with the peephole, a rearward viewing port, and an eyecup. The security cover further includes a shutter mechanism that is manually repositionable from a closed position to an opened position via engagement of an actuator. In operation, the security cover is coupled to a door such that it covers the door viewer.