Abstract:
The present invention relates to a secure barrier for an underground valve box. The device may have a bolt and a nut for adjusting the length of the bolt to position curved plates to press against the inner circumference of a cylindrical valve box. The bolt housing may include a flange that protrudes through a slot in a horizontal metal plate. The plate may have handles for ease of lifting and replacement of the plate. The protruding flange may feature a hole for insertion of a padlock. When the padlock is secured, the plate cannot be removed from the cylindrical valve box as the adjustable bolt housing cannot move sufficiently to retract the curved plates from the inner cylindrical surface of the valve box. Thus, only authorized personnel with the proper padlock key or combination can operate the valve, deterring vandals.

Description:
BACKGROUND OF THE INVENTION 
     A common issue with excavations and other types of holes, spaces, and enclosures, involves the danger of leaving the space open or uncovered. A person or animal may access the space causing injury, property damage, stop or start utilities, vandalism, or other undesired situations. Authorized individuals, such as utility workers, need access to enclosed spaces. Valve box covers, manhole covers, and other tops, covers, and blocks exist to keep out unauthorized access. 
     Valve boxes (sometimes referred to as “valve vaults”) are commonly used to secure access to buried valves, conduits, or pipe sections. The valve boxes may be covered to protect access to supplies of water, gas, electricity, telecommunication, cable, utilities, and other such flowing or transmission conduits. The valve box is often cylindrical with a lid or cap to protect the valve, prevent animals and people from entering the enclosed area, and to support the weight of vehicles passing over the valve box. Valve boxes often are elongated hollow housings capped at an upper end by a collar or the like, wherein a cap, lid, top, or similar barrier may be removed by a properly authorized person to allow access to the valve, such as by a wrench or other tool. A recurring problem with valve box access is that unauthorized persons may remove the cover, such as to maliciously or accidentally tamper with a valve. Unintended actuation or other operation of a valve disrupts systems, such as utilities. The valve box may be constructed of metal (such as cast iron), concrete, plastic, or other suitable materials. Exemplary valve boxes may be the type of valve boxes available from Bingham &amp; Taylor at 601 Nalle Place, Culpeper, Va. 22701, U.S.A. 
     Many present devices for securing access to enclosed spaces are cumbersome and contain complicated mechanisms that are costly, difficult to open and secure, and difficult to manufacture. 
     It would be advantageous to provide an apparatus, method, and system that would include one or more of the features of 1) ease of manufacture; 2) uncomplicated mechanisms; 3) no power supply necessary for operation; 4) simple to allow access to enclosed spaces; and 5) securely preventing unauthorized access to enclosed spaces. 
     SUMMARY OF THE INVENTION 
     In one aspect of the present invention, an enclosure covering device may comprise; a top plate, a screw mechanism extending through an aperture in the top plate, the screw mechanism having an upper portion above the top plate and a lower portion below the top plate, a movable arm extending radially from the screw mechanism and operatively coupled to the lower portion of the screw mechanism such that the movable arm may be moved from a retracted position to a deployed position by turning a nut on the screw mechanism, and a locking mechanism preventing access to the screw mechanism, wherein the locking mechanism comprises a padlock engaged with the upper portion of the screw mechanism. 
     In another aspect of the present invention, an enclosure covering device may comprise; a substantially circular top plate; a screw mechanism comprising an eyelet extending above the substantially circular top plate and an externally threaded portion extending below the substantially circular top plate with a sleeve coupled to the externally threaded portion and extending below the substantially circular top plate; an internally threaded nut matingly engaged with the externally threaded portion of the screw mechanism for turning in a direction substantially perpendicular to the sleeve to urge a sliding collar radially outward; a fixed collar situated below the substantially circular top plate; the sliding collar coupled to the sleeve, opposite of the fixed collar; the sliding collar extending radially from the screw mechanism such that the sliding collar may be moved from a retracted position to a deployed position by turning the internally threaded nut on the screw mechanism; and a locking mechanism preventing access to the screw mechanism. 
     In yet another aspect of the present invention, a method for covering an enclosure, the method may comprise; placing a lower portion of an enclosure covering device into an enclosure, the enclosure covering device comprising; a top plate with a dimension permitting the top plate to rest near the top of the enclosure; a screw mechanism comprising an eyelet extending above the top plate and an externally threaded portion extending below the top plate with a sleeve coupled to the externally threaded portion and extending below the top plate; an internally threaded nut matingly engaged with the externally threaded portion of the screw mechanism for turning in a direction substantially perpendicular to the sleeve to urge the sleeve radially outward; a stationary arm situated below the top plate; a movable arm coupled to the sleeve, opposite of the stationary arm; a movable arm extending radially from the screw mechanism such that the movable arm may be moved from a retracted position to a deployed position by turning the internally threaded nut on the screw mechanism; and engaging the upper portion of the screw mechanism to more the movable arm from a retracted position to a deployed position, causing the movable arm to engage an interior side of the enclosure when in the deployed position; and locking the screw mechanism to prevent access to the screw mechanism, wherein the step of locking the screw mechanism comprises the step of: locking the top plate to the screw mechanism. 
     These and other aspects, objects, features and advantages of the present invention, are specifically set forth in, or will become apparent from the following detailed description of an exemplary embodiment of the invention when read in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a screw mechanism, according to an embodiment of the present invention; 
         FIG. 2A  is an elevational view of a screw mechanism and top lid, according to another embodiment of the present invention; 
         FIG. 2B  is a view of an underside of a screw mechanism and a top lid, according to yet another embodiment of the present invention; 
         FIG. 3  is an exploded view of a screw mechanism and a top lid, according to still yet another embodiment of the present invention; 
         FIG. 4  shows a screw mechanism, with a movable arm deployed within an enclosure, according to a further embodiment of the present invention; 
         FIG. 5  shows a top lid covering the top of an enclosure while matingly engaging with a screw mechanism including an eyelet protruding from an aperture in the top lid, according to a yet further embodiment of the present invention; 
         FIG. 6  shows a top lid covering the top of a valve box while matingly engaging with a screw mechanism including an eyelet protruding from an aperture in the top lid, according to a further embodiment of the present invention; 
         FIG. 7  shows a screw mechanism, with a movable arm deployed within a valve box, without a top lid or valve box cover, according to a still further embodiment of the present invention; 
         FIG. 8  shows a cross-sectional view of a screw mechanism deployed within an enclosing space, according to yet another embodiment of the present invention; and 
         FIG. 9  shows a flowchart depicting an exemplary method, according to a still further embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The following detailed description is of the best currently contemplated modes of carrying out the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims. 
     This invention relates generally to an apparatus for securing an underground space or enclosure, such as a manhole, a well, a utility valve box, catch basins, cisterns, or other underground or enclosed spaces or containers. 
     More specifically, this invention relates to an apparatus for securing an underground space or enclosure such that the apparatus is adjustable to accommodate most configurations of utility valve boxes. While the present invention may be described herein as applying specifically to underground valve boxes, it is to be understood that the invention is suitable for similar applications, such as for manhole access, water supply systems, sewer systems, wells, utility access, and other spaces or enclosures, above ground and underground. It is also to be understood that although the invention may be described as pertaining to the term “valve box,” the invention also is suitable for use with an enclosed space called a “valve vault.” 
     Many valves for flowing substances must be situated below ground to reduce the likelihood of freezing, unauthorized access, avoiding hazards for pedestrians, animals, or vehicles, aesthetic reasons, and for other reasons. Such valves are often situated at the bottom of a short shaft with an opening at ground level, such that the opening is closed by a cover. 
     The present invention provides a mechanism for securing a top lid as a cover for an enclosure regardless of the shape of the lid or enclosure (e.g., circular or rectangular) or size of the shaft or space. The present invention provides for rapid and easy installation into an open space while preventing unauthorized access, such as by vandals or saboteurs. Movable or expandable arms or members may be used to engage with the interior surfaces of a valve box from a retracted position to an extended or engaged position such that the members or arms engage the walls of the valve box. In one embodiment, one arm or member may be movable and the other arm or member may be relatively stationary. 
     In one embodiment the present invention may comprise a cover assembly for covering an opening of a shaft in the ground, the assembly comprising a cover plate for covering the opening and an expandable anchor assembly adapted to engage the walls of the shaft to anchor the cover plate in position. The expandable anchor assembly may comprise at least one shaft-engaging portion that moves between retracted and extended positions such that a movable shaft-engaging portion may be initially retracted for the anchor assembly to be inserted into the shaft and extended to engage with the shaft. Shaft-engaging shoes may be at distal ends of one or more shaft-engaging portions wherein one or more of the shoes may be movable in opposing directions. Expansion and contraction of the anchor assembly may be accomplished by rotating a nut or other fastener. 
     The cover of a single shape may cover a smaller opening of any shape and therefore does not need to match the shape of the valve box opening. The mechanism of the present invention is disposed on the underside of the cover and actuable from the outside of the valve box (e.g, from the top side of the cover). 
     A clear understanding of the key features of the invention summarized above may be attained by referencing the below figures, which illustrate the method and system of the invention, although it will be understood that such drawings depict various exemplary embodiments of the invention and, therefore, are not to be considered as limiting scope with regard to other embodiments which the invention is capable of contemplating. 
       FIG. 1  shows a screw mechanism  100  according to an exemplary embodiment of the present invention. The screw mechanism may be manufactured from a suitable, durable material, such as cast iron or steel. A first arm  102  may be a stationary arm such that the first arm  102  does not move relative to a second arm  104 , which may be a movable arm. A sleeve  106  may be concentric with an externally threaded portion  108  such as an externally threaded bolt. The sleeve  106  may be cylindrical with a cylindrical void for insertion of the externally threaded portion  108 . 
     A handle  110  may be used to rotate a nut  132 , such as an internally threaded fastener, such as a hexagonal nut fitting. As the nut  132  is rotated in one direction, the sleeve  106  and the second arm (movable arm)  104  may move in a direction opposite to the first arm (stationary arm)  102  to engage with an interior surface of a valve box by contact with an engagement surface  114  while the first arm  102  may be engaged or pressed against an interior surface of the valve box through contact with an engagement surface  112 . If the nut  132  is rotated in another direction, the sleeve  106  and the second arm (movable arm)  104  may move in a direction towards the first arm (stationary arm)  102  to disengage from an interior surface of a valve box by retracting an engagement surface  114  while the first arm  102  may be disengaged from an interior surface of the valve box through stopping or discontinuing contact with an engagement surface  112 . Rotation of the nut  132  may urge the arms  102 ,  104  outwardly towards opposite walls of a valve box or retract inwardly. An inner surface  116  of the first arm may serve to facilitate grasping the screw mechanism. Likewise, an inner surface  118  may facilitate grasping the screw mechanism  100  from the movable arm region. Prongs  120  and  122  may extend distally from the first arm  102  while prongs  124  and  126  may extend distally from the second arm  104 . 
     Optionally, one or more additional arms may be used, such as arms (not shown) perpendicular to the first arm  102  and the second arm  104  to further block access to a valve box. An eyelet  128  may extend substantially orthogonally from an outer surface of the sleeve, with an aperture  130  therein for extending through an aperture of a cover to secure the cover to a valve box, as described below. 
       FIG. 2A  shows an elevational view of a screw mechanism  200  and a top lid  218 . As can be seen in  FIG. 2A , an eyelet  216  protrudes through aperture  224  to provide an eyelet aperture  226  for shackling a lock or chain thereto to secure the top lid  218  to the screw mechanism  200 . The first arm  202 , with prongs  206 ,  208 , may be stationary relative to the top lid  218  and the second arm  204 , which may comprise prongs  210 ,  212 . One or more handles  220 ,  222  may be used to lift the top lid  218  from the enclosure and to lower the top lid  218  to replace the top lid  218 . The externally threaded portion may translate outward radially to move the second arm  204  away from the stationary arm  202  and inward radially to move the second arm  204  towards the first arm  202 . 
       FIG. 2B  shows a view of an underside of a screw mechanism and a top lid, according to yet another embodiment of the present invention, further demonstrating the structure of the present invention. A recess  230  may serve for receiving a screw, such as a button head  236 , for adjusting, calibrating, or otherwise setting the interaction between a hollow sleeve  232 , the externally threaded portion  214  with a groove or slot  240 , and the nut  234 . 
       FIG. 3  shows an exploded view of the present invention  300  according another embodiment of the present invention. A first arm, also known as a fixed collar  302 , may receive a spring  338  within a hollow sleeve  332  for interaction with a second arm, also known as a sliding collar  304 , with a nut  334  for securing the sliding collar in place when deployed within a valve box. The spring  338  may provide resilience and force to ensure that the sliding collar sufficiently urges towards an interior wall of a valve box. An eyelet  316  may protrude through lid aperture  324  to provide an eyelet aperture  326  for shackling a lock or chain thereto to secure the top lid  318  to the screw mechanism  300 . The fixed collar  302 , with prongs  306 ,  308 , may be stationary relative to the top lid  318  and the sliding collar  304 , which may comprise prongs  310 ,  312 . One or more handles  320 ,  322  may be used to lift the top lid  318  from a valve box or other enclosure and to lower the top lid  318  to replace the top lid  318  to a position above the screw mechanism  300 . An externally threaded portion of the sliding collar  304  may translate outward radially to move the sliding collar  304  away from the fixed collar  302  and inward radially to move the sliding collar  304  towards the fixed collar  302 . 
     The externally threaded portion  314  may have therein a slot or groove  340 , in line with a major axis of the externally threaded portion  314 . The groove  340  may maintain proper alignment between the fixed collar  302  and the sliding collar  304 . A recess  330  may serve for receiving a screw, such as a button head  336 , for locking in position the hollow sleeve  332  with the externally threaded portion  314  of the sliding collar  304 . The screw  336  may be turned for adjusting, calibrating, or otherwise setting the interaction between a hollow sleeve  332 , the externally threaded portion  314 , the groove  340 , and the nut  334 . When the externally threaded portion  314  is inserted into the hollow sleeve  332 , a male portion of the screw  336  may fit into the slot or groove  340  for further securing the sliding collar  304  when deployed within an enclosure, such as a valve box, and for aligning the sliding collar  304  with the fixed collar  302 . 
       FIG. 4  shows the present invention  400  wherein an enclosure  402  has a screw mechanism  404  deployed within the enclosure  402 . A sleeve  412  holds an externally threaded portion  414  to maintain a fixed collar  406  in contact with an inner surface  408  of the enclosure  402 . A movable collar  410  may be deployed by being extended to press against the inner surface  408  of the enclosure  402  by rotating the nut  418 , with a tool (such as a wrench) or by moving optional handle  416 . A sleeve eyelet  420  with an aperture  422  may extend outward from the screw mechanism  404 , such as extending perpendicularly from the sleeve  412 . 
       FIG. 5  shows an enclosure  500  with an interior surface  502 , wherein a top lid  504  fits inside the interior dimensions  502  to rest on top of the enclosure  500  (e.g., a valve box). A screw mechanism, such as of the type discussed previously in  FIGS. 1-4 , may be installed within the enclosure  500  and below the top lid  504  with an eyelet  506  protruding through a lid aperture  512  to present an eyelet aperture  508  for inserting a shackle of a padlock, chain, or other security device to prevent removal of the top lid  504 . A handle  510  may be used for removing, lifting, lowering, and replacing the top lid  504  to cover the enclosure  500 . 
       FIG. 6  shows another embodiment, wherein an enclosure  600  (such as a valve box or valve vault) has an interior surface  602 . A top lid  604  may fit within the interior surface  602 , to rest near the top of the enclosure  600 . A screw mechanism, such as of the type discussed previously in  FIGS. 1-4 , may be installed within the enclosure  600  and below the top lid  604  with an eyelet  606  protruding through a lid aperture  614  to present an eyelet aperture  608  for inserting a shackle of a padlock, chain, or other security device to prevent removal of the top lid  604  from the enclosure  600 . One or more handles  610 ,  612  may be used for removing, lifting, lowering, and replacing the top lid to cover the enclosure  600 . A cover  616  may be placed at the opening of the enclosure  600  to protect the enclosure  600  from environmental occurrences, such as rain, wind, snow, debris, and other events, along with providing a surface for vehicles to travel without interruption. 
       FIG. 7  shows yet another embodiment of the present invention  700  wherein an enclosure  702  has a screw mechanism  704  deployed within the enclosure  702 , similar to how the screw mechanism was deployed in  FIG. 4  (described above). A sleeve  712  holds an externally threaded portion  714  to maintain a sliding collar  716  in contact with an inner surface  718  of the enclosure  702 . A fixed collar  720  may be deployed by being extended to press against the inner surface  718  of the enclosure  702  by rotating the nut  722 , with a tool (such as a wrench). Prongs  730 ,  732  may be essentially parallel with a major axis of the screw mechanism  704  for further support, such as for supporting a top lid such that the top lid may rest upon the prongs  730 ,  732 . The top lid also may rest upon a protrusion  734  that projects inwardly from the inner surface  718  of the enclosure  702 . A sleeve eyelet  724  with an aperture  726  may extend outward from the screw mechanism  704 , such as extending perpendicularly from the sleeve  712 . 
       FIG. 8  shows a cross-sectional view of a screw mechanism  802  deployed within an enclosing space  800 , according to yet another embodiment of the present invention. An externally threaded portion  804  may be inserted coaxially within a recess of a sleeve  806 , optionally with a spring  830  inserted within a hollow of sleeve  806 . The externally threaded portion may be moved towards an inner wall  816  of the enclosure  800  by rotating handle  808  and/or a nut  828  several turns until a movable arm  814  is pressed securely against the inner wall  816  while a stationary arm  812  may maintain contact with the inner wall  816  and sufficient pressure on the inner wall  816  such that the screw mechanism  802  secures a sleeve eyelet  810  that protrudes out of the top lid  824  through a top lid aperture  830 . A padlock  820  may be used to lock the top lid  824  in place on top of the enclosure  800  by placing a shackle  822  of the padlock  820  into an eyelet aperture  818  so that the top lid  824  may not be removed without opening the padlock  820  to free up access to the enclosure  800 . A handle  826  may be grasped to carry the top lid  824  when opening and closing the enclosure  800 . 
     Turning to  FIG. 9  an exemplary method is illustrated in a flow chart. A method  900  for covering an enclosure may comprise; in Step  902 , placing a lower portion of an enclosure covering device into an enclosure, the enclosure covering device comprising a top plate with a dimension permitting the top plate to rest near the top of the enclosure, a screw mechanism comprising an eyelet extending above the substantially circular top plate and an externally threaded portion extending below the substantially circular top plate with a sleeve coupled to the externally threaded portion and extending below the substantially circular top, an internally threaded nut matingly engaged with the externally threaded portion of the screw mechanism for turning in a direction substantially perpendicular to the sleeve to urge the sleeve radially outward, a stationary arm situated below the substantially circular top plate, a movable arm coupled to the sleeve, opposite of the stationary arm, a movable arm extending radially from the screw mechanism such that the movable arm may be moved from a retracted position to a deployed position by turning an internally threaded nut on the screw mechanism, and a locking mechanism preventing the screw mechanism from turning a full revolution; a Step  904  of engaging the upper portion of the screw mechanism to move the movable arm from a retracted position to a deployed position, and a Step  906  of causing the movable arm to engage an interior side of the enclosure when in the deployed position. A Step  908  may comprise locking the screw mechanism to prevent turning the screw mechanism a full revolution and/or preventing removal of the top lid, wherein the step of locking the screw mechanism comprises the steps of; a Step  910  of providing a padlock for securing the screw mechanism by inserting a shackle of the padlock into the eyelet of the upper portion of the screw mechanism while maintaining the padlock above the top plate. 
     It should be understood, of course, that the foregoing relates to exemplary embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims. Furthermore, a method herein described may be performed in one or more sequences other than the sequence presented expressly herein.